Collections

5 datasets

Oliveira MF et al. · 2024 · bioRxiv

Spatial & temporal transcriptomic atlas of mouse intestinal regeneration in the jejunum (Visium HD, radiation time-course).

Shi L et al. · 2026 · Nature immunology

Liu R et al. · 2026 · Proceedings of the National Academy of Sciences of the United States of America

Lee H et al. · 2026 · The Journal of allergy and clinical immunology

GSE334924

Xue Z et al. · 2025 · Nature communications

Jachim SK et al. · 2026 · Osteoarthritis and cartilage

Rao N et al. · 2026 · Nature communications

GSE342738

GSE342738

Grohar PJ et al. · 2026 · Nature medicine

Grohar PJ et al. · 2026 · Nature medicine

GSE345644

Zhang M et al. · 2023 · Nature

Yao Z et al. · 2023 · Nature

Hewitt MN et al. · 2025 · Europe PMC

Bandyopadhyay S et al. · 2024 · Cell

Barlow GL et al. · 2025 · eLife

2 datasets

Han X et al. · 2026 · Nature genetics

2 datasets

2 datasets

1 dataset

1 dataset

2 datasets

2 datasets

1 dataset

2 datasets

2 datasets

3 datasets

3 datasets

2 datasets

1 dataset

12 datasets

Guo C et al. · 2023 · Clinical and translational medicine

Barrozo ER et al. · 2024 · American journal of obstetrics and gynecology

Anton PE et al. · 2024 · Brain, behavior, and immunity

Asp M et al. · 2019 · Cell

Ji AL et al. · 2020 · Cell

Hahn O et al. · 2023 · Cell

Heiser CN et al. · 2023 · Cell

Ziblat A et al. · 2024 · Cell reports

Lyubetskaya A et al. · 2022 · Cell reports methods

Meylan M et al. · 2022 · Immunity

Barrozo ER et al. · 2023 · Med (New York, N.Y.)

Gracia Villacampa E et al. · 2021 · Cell genomics

Andersson A et al. · 2021 · Nature communications

Marklund M et al. · 2022 · Nature communications

Liu T et al. · 2022 · Nature communications

Schäbitz A et al. · 2022 · Nature communications

Mirzazadeh R et al. · 2023 · Nature communications

Canela VH et al. · 2023 · Nature communications

Fang J et al. · 2023 · Nature communications

Xue M et al. · 2023 · Nature communications

Erickson A et al. · 2022 · Nature

Karras P et al. · 2022 · Nature

Kathe C et al. · 2022 · Nature

Lake BB et al. · 2023 · Nature

Kanemaru K et al. · 2023 · Nature

Matchett KP et al. · 2024 · Nature

Bergenstråhle L et al. · 2022 · Nature biotechnology

McKellar DW et al. · 2023 · Nature biotechnology

Vicari M et al. · 2024 · Nature biotechnology

Madissoon E et al. · 2023 · Nature genetics

Fonseca MAS et al. · 2023 · Nature genetics

Maynard KR et al. · 2021 · Nature neuroscience

McKellar DW et al. · 2021 · Communications biology

Mantri M et al. · 2022 · Nature cardiovascular research

14 datasets

Fan Y et al. · 2022 · Europe PMC

Giraud J et al. · 2022 · Preprint

Valdeolivas A et al. · 2023 · bioRxiv

Pakula H et al. · 2023 · bioRxiv

Voigt AP et al. · 2023 · bioRxiv

Ortiz C et al. · 2020 · Science advances

Ståhl PL et al. · 2016 · Science (New York, N.Y.)

Maniatis S et al. · 2019 · Science (New York, N.Y.)

Mauduit O et al. · 2022 · Frontiers in immunology

Lin W et al. · 2023 · Frontiers in pharmacology

2 datasets

To define the cellular composition and spatial architecture of the tumor micoenvironment, we combined single-cell RNA-sequencing, spatial transcriptomics, and multiplexed ion-beam imaging from 10 patient cutaneous squamous cell carcinoma tumors and site-matched normal skin

The mammalian brain contains many specialized cells that develop from a thin sheet of neuroepithelial progenitor cells. Single-cell transcriptomics revealed hundreds of molecularly diverse cell types in the nervous system, but the lineage relationships between mature cell types and progenitor cells are not well understood. Here we show in vivo barcoding of early progenitors to simultaneously profile cell phenotypes and clonal relations in the mouse brain using single-cell and spatial transcriptomics. By reconstructing thousands of clones, we discovered fate-restricted progenitor cells in the mouse hippocampal neuroepithelium and show that microglia are derived from few primitive myeloid precursors that massively expand to generate widely dispersed progeny. We combined spatial transcriptomics with clonal barcoding and disentangled migration patterns of clonally related cells in densely labelled tissue sections. Our approach enables high-throughput dense reconstruction of cell phenotypes and clonal relations at the single-cell and tissue level in individual animals and provides an integrated approach for understanding tissue architecture.

Mouse brain 10x Genomics Visium Spatial Transcriptomics profiles sequence either with Illumina for standard profiling and Nanopore promethION long read sequencer for full-length profiling.

To study cell heterogeneity and state transitions in the developing urinary tract we performed spatial transcriptomics from the trunk of E9.5 Pax2GFP mouse embryos using the 10X Genomics Visium Spatial Gene Expression protocol

Spatial transcriptomics of saline- and LPS-injected Aldh1l1egfp mice 24 h after injection

The limitation of single-cell or bulk transcriptomic profiling is the lack of spatial topographical context. Spatial transcriptomics (ST) allows sequencing of polyadenylated transcripts from a tissue section which can be spatially mapped onto the histological brightfield image using an array of barcoded oligo-dT capturing probes. Using the 10X Visium platform, here, we unbiasedly characterized the spatial transcriptomic landscape of murine colon in steady state and during mucosal healing upon dextran sodium sulfate (DSS) induced injury

We developed a method, CellDART, which estimates the spatial distribution of cells defined by single-cell level data using domain adaptation of neural networks, and applied to the spatial mapping of human lung tissue. The neural network that predicts the cell proportion in a pseudospot, a virtual mixture of cells from single-cell data, is translated to decompose the cell types in each spatial barcoded region. CellDART elucidated the cell type predominance defined by the human lung cell atlas across the human lung tissue compartments and it corresponded to the known prevalent cell types.

The patterning and ossification of the mammalian skeleton requires the coordinated actions of both intrinsic bone morphogens and extrinsic neurovascular signals, which function in a temporal and spatial fashion to control mesenchymal progenitor cell (MPC) fate. Here we show genetic inhibition of Tropomyosin receptor kinase A (TrkA) sensory nerve innervation of the developing cranium results in premature calvarial suture closure, associated with a decrease in suture MPC proliferation. In vitro, axons from peripheral afferent neurons derived from DRGs of wild type mice induce MPC proliferation in a spatially-restricted manner via a soluble factor when co-cultured in microfluidic chambers. Comparative spatial transcriptomic analysis of the cranial sutures in vivo confirmed a positive association between sensory axons and proliferative MPCs. SpatialTime analysis across the developing suture revealed regional-specific alterations in BMP and TGFβ signaling pathway transcripts in response to TrkA inhibition. RNA sequencing of DRG cell bodies following direct axonal co-culture with MPCs confirmed alterations in BMP/TGFβ signaling pathway transcripts. Among these, the BMP inhibitor FSTL1 (Follistatin-like 1) replicated key features of the neural-to-bone influence, including mitogenic and anti-osteogenic effects via inhibition of BMP/TGFβ signaling. Taken together, our results demonstrate that sensory nerve-derived signals, including FSTL1, function to coordinate cranial bone patterning by regulating MPC proliferation and differentiation in the suture mesenchyme.

The underlying mechanisms of ventricular remodeling after myocardial infarction (MI) remain largely unknown. Here, we performed an integrative analysis of spatial transcriptomics and single-nucleus RNA-seq in a murine MI model and found that mechanical stress-response genes are expressed at the border zone and play a critical role in left ventricular remodeling following MI. An integrative analysis of single-nucleus RNA-seq and spatial transcriptome of the heart tissue after MI identified the unique cluster that appeared at the border zone in an early stage, highly expressing mechano-sensing genes such as Csrp3. AAV9-mediated gene silencing and overexpression of Csrp3 demonstrated that upregulation of Csrp3 plays critical roles in preventing cardiac remodeling after MI via regulation of genes associated with mechano-sensing. Overall, our study not only provides an insight into spatiotemporal molecular changes following MI but also highlights that the mechano-sensing genes at the border zone act as adaptive regulators of left ventricular remodeling.

In the skin, tissue injury results in fibrosis in the form of scars composed of dense extracellular matrix deposited by fibroblasts. The therapeutic goal of regenerative wound healing has remained elusive in part because principles of fibroblast programming and adaptive response to injury remain incompletely understood. Here, we present a multimodal -omics platform for the comprehensive study of cell populations in complex tissue, which has allowed us to characterize the cells involved in wound healing across both time and space. We employ a stented wound model that recapitulates human tissue repair kinetics and multiple Rainbow transgenic lines to precisely track fibroblast fate during the physiologic response to injury. Through integrated analysis of single cell chromatin landscapes and gene expression states, coupled with spatial transcriptomic profiling, we are able to impute fibroblast epigenomes with temporospatial resolution. This has allowed us to define the mechanisms controlling cell fate during migration, proliferation, and differentiation following tissue injury and thereby reexamine the canonical phases of wound healing. We show that wounding triggers a polyclonal proliferation of tissue-resident, mechano-responsive fibroblasts, the subpopulations of which inhabit spatially-distinct regions within the wound and harbor distinct activities. These findings have broad implications for the study of tissue repair in complex organ systems.

Spatial transcriptomics of six surgically-resected human brain metastasis samples

We collected HNSCC primary tumor sections from head and neck squamous cell carcinoma patients at the Taipei Veterans General Hospital (TVGH) for 10x Genomics Visium analysis.

After intracranial hemorrhages, heme is released from cell-free hemoglobin. This red blood cell toxin may drive secondary brain injury at the hematoma-brain interface. This study aimed to generate a spatially resolved map of the transcriptome-wide gene expression changes in the heme-exposed brain and define the potential therapeutic activity of the heme-binding protein hemopexin.

We optimized and validated a female bilateral ischemia reperfusion injury model. Using the 10X Genomics Visium Spatial Gene Expression solution, we generated spatial maps of gene expression across the injury and repair time course, and applied two open-source computational tools, Giotto and SPOTlight, to increase resolution and measure cell-cell interaction dynamics. An ischemia time of 34 minutes in a female murine model resulted in comparable injury to males across the time course of injury and repair. We report increased resolution of cell and gene expression with Giotto, a computational toolbox for spatial data analysis. Using a seeded non-negative matrix regression (SPOTlight) to deconvolute the dynamic landscape of cell-cell interactions, we find that injured proximal tubule cells are characterized by increasing macrophage and lymphocyte interactions even at 6 weeks after injury, consistent with a pro-inflammatory role for this cell state. In this transcriptomic atlas, we defined region-specific and injury-induced loss of differentiation markers and their re-expression during repair, as well as region-specific injury and repair transcriptional responses. Lastly, we created a data visualization web application for the scientific community to explore these results (http://humphreyslab.com/SingleCell/).

As observed in mice with genetic depletion of stem cells, epithelial plasticity is a critical component of tissue repair in response to injury; however, the physiological relevance of this process and the involved progenitor populations are not well understood. Severe respiratory viral infection and chronic lung disease share pathological features including stem cell loss in the gas-exchange regions, basal cell (BC) hyperplasia in small airways, and innate immune activation. Collectively, these processes contribute to epithelial remodeling and loss of diffusion capacity. Here, we show that small airways harbor a previously undescribed lineage of secretory cells, intralobar serous (IS) cells, that are activated to assume BC fates following influenza virus infection. Nascent BC were distinguished from pre-existing BC by high expression of IL-22Ra1 and a dependency on innate immune activation and local IL-22 production for self-renewal and colonization of injured alveoli. Resolution of virus-elicited inflammation and the associated decline in IL-22 signaling resulted in basal to serous re-differentiation in repopulated alveoli, and increased local expression of antimicrobial factors, but failed to replace normal alveolar epithelium. We define a mechanism whereby epithelial plasticity confers protection against mortality from acute respiratory viral infection but has potential to contribute to progressive lung remodeling and life-threatening declines in lung function among patients with chronic lung disease.

Ageing is a physiological process that manifests through progressive molecular, cellular, and systemic changes. Female reproductive potential gradually declines with age as oocyte quality and quantity decline. The purpose of this study was to better understand the spatiotemporal dynamics of the ovary.

We use spatial transcriptomics to establish regional transcriptional profile of neonatal heart tissue obtained at indicated timpoints after apical resection surgery.

The microenvironment of lymph node metastasized tumors (LNMT) determines tumor progression and response to therapy, but a systematic study of LNMT is lacking. Here, we generate single-cell maps of primary tumors (PTs) and paired LNMTs in 8 breast cancer patients. We demonstrate that the activation, cytotoxicity, and proliferation of T cells are suppressed in LNMT compared with PT. CD4+CXCL13+ T cells in LNMT are more likely to differentiate into an exhausted state. Interestingly, LAMP3+ dendritic cells in LNMT display lower T cell priming and activating ability than in PT. Additionally, we identify a subtype of PLA2G2A+ cancer-associated fibroblasts enriched in HER2+ breast cancer patients that promotes immune infiltration. We also show that the antigen-presentation pathway is downregulated in malignant cells of the metastatic lymph node. Altogether, we characterize the microenvironment of LNMT and PT, which may shed light on the individualized therapeutic strategies for breast cancer patients with lymph node metastasis.

Analysis of CITE-seq data , Nuclei RNA-seq data and single cell RNA-seq data on CD45+ and CD45- cells isolated from the livers of mice fed a standard diet (SD) or western diet (WD; fat, cholesterol and sugar), from healthy and steatotic human livers, from hamster liver, pig liver, chicken liver, monkey liver and zebrafish liver. We also performed Spatial Transcriptomics analysis on heatlhy mouse livers, NAFLD mouse livers, healthy human livers and steatotic human livers.

The mammalian brain can be divided into distinct structural and functional regions to perform a variety of diverse functions, but during normal aging, exactly how each region is affected, and the information interaction changes between different regions, remains largely unknown. To gain a better insight into these processes, here we generate a single-cell spatial transcriptomic (ST) atlas of young and old mice brains involving cerebrum, brain stem and fiber tracts regions. Based on the unbiased classification of spatial molecular atlas, 27 distinguished brain spatial domains were obtained, which are similar to known anatomical regions, but slightly different. Through differential expression analysis and gene set enrichment analysis (GSEA), we identified aging-related genes and pathways that vary in a coordinated or opposite manner across regions. Combined with single-cell transcriptomic data, we characterized the spatial distribution of cell types, identified an up-regulated gene Ifi27 across regions and cell types in VIS region. Through ligand-receptor interaction analysis, we identified all possible information interaction changes between regions with aging. In summary, we establish a brain spatial molecular atlas (accessible online at https:) to provide a rich resource of spatially differentially expressed genes and information interaction, which may help to understand aging and provide novel insights into the molecular mechanism of brain aging.

The cellular architecture of a tumor has a major impact on cancer outcome, and thus there is interest in identifying genes controlling the tumor microenvironment (TME). While CRISPR screens are helping uncover genes regulating many cell-intrinsic processes, existing approaches are suboptimal for identifying gene functions operating extracellularly or within a tissue context. To address this, we developed an approach for spatial functional genomics called Perturb-map, which utilizes protein barcodes (Pro-Code) to enable spatial detection of barcoded cells within tissue. We applied Perturb-map to knockout dozens of genes in parallel in a mouse model of lung cancer and simultaneously assessed how each knockout influenced tumor growth, histopathology, and immune composition. Additionally, we paired Perturb-map and spatial transcriptomics for unbiased molecular analysis of Pro-Code/CRISPR lesions. Our studies found in Tgfbr2 knockout lesions, the TME was converted to a fibro-mucinous state and T-cells excluded, concomitant with upregulated TGFb and TGFb-mediated stroma activation, suggesting Tgfbr2 loss on lung cancer cells increased TGFb bioavailability and enhanced its suppressive effects on the TME. These studies establish Perturb-map for functional genomics within a tissue at single cell-resolution with spatial architecture preserved.

Lack of relevant animal models and cell lines hampers the understanding of hepatoblastoma and identification of therapeutic targets. We report a hepatoblastoma murine model that faithfully recapitulates the pathological features of mixed fetal and embryonic hepatoblastoma, with transcriptomics resembling the high-risk gene signatures of human disease

Lymphatic dysfunction is an integral aspect of rheumatoid arthritis (RA) pathogenesis. During "Early" arthritis in tumor necrosis factor transgenic (TNF-Tg) mice, the joint-draining popliteal lymph nodes (PLNs) dramatically expand in volume. After a prolonged expansion phase, at ~8-months-old the PLNs stochastically collapse with reduced bone volume and associated onset of "Advanced" inflammatory-erosive arthritis in affected joints. Through this pathologic process, B-cells are known to translocate into the PLN sinuses. Bulk tissue approaches (i.e. bulk genomics, flow cytometry, and ex vivo cell cultures) have been insufficient to specifically evaluate the transcriptional changes of B-cells within the sinuses of TNF-Tg PLNs. Thus, we utilized spatial transcriptomics technology to evaluate transcriptional changes in sinus B-cells and the functional genomic relationships with arthritic severity.

Quadricep sections of 10µm thick were placed on Visium spatial transcriptomics slide to obtain spatial datasets for these skeletal muscle sections

Understanding of the spatial architecture of the primary NPC microenvironment as well as the co-localization and cell-cell communication between tumor and immune cells

CD4+ T cells play a critical role in sustaining the effector function of CD8+ T cells during chronic viral infection. When CD4+ T cell “help” is absent, CD8+ T cells enter a dysfunctional state, losing their capacity for viral control. Here, we applied spatial transcriptomics to explore cellular localization and potential interaction between key immune cell subsets during chronic LCMV Clone 13 infection.

Aging is known to alter the host repsonse to influenza infection. Here, we use 10x Visium spatial sequencing to identify spatial changes in mRNA expression of left lungs of young (16-week-old) and aged (80-week-old) mice following influenza infection.

Spatial Transcriptomics (Visium) of 12 coronal brain sections from 6 months old female Inpp5dfl/fl/Cx3cr1CreER/+ crossed to APPKM670/671NL/PSEN1Δexon9 (PSAPP) mice and treated with either cornoil or tamoxifen (75 mg/kg) at 3 months of age for 5 consecutive days

Transcriptional heterogeneity among malignant cells of a tumor has been studied in individual cancer types and shown to be organized into cancer cell states; however, it remains unclear to what extent these states span tumor types, constituting general features of cancer. Here, we perform a pan-cancer single-cell RNA-Seq analysis across 15 cancer types and identify a catalog of gene modules whose expression defines recurrent cancer cell states including ‘stress’, ‘interferon response’, ‘epithelial-mesenchymal transition’, ‘metal response’, ‘basal’ and ‘ciliated’. Spatial transcriptomic analysis linked the interferon response in cancer cells to T cells and macrophages in the tumor microenvironment. Using mouse models, we further found that induction of the interferon response module varies by tumor location and is diminished upon elimination of lymphocytes. Our work provides a framework for studying how cancer cell states interact with the tumor microenvironment to form organized systems capable of immune evasion, drug resistance, and metastasis.

Immune checkpoint inhibitors unleash inhibitory signals on effector T cells inflicted by tumor and surrounding stromal cells. Despite the great success of PD-1 inhibitors in a fraction of cancer patients, lack of checkpoint molecule expression and persistence of immunosuppressive cells limit the effects of the therapy. To overcome the limitations, combination therapies or direct stimulation of myeloid cells are being investigated. Nonetheless, combination therapies increase the incidence of side effects, and a single agent co-stimulating T cell and myeloid populations might be a better strategy. Exploring single cell RNA sequencing data from multiple human cancers and mouse tumor model, we found pleiotropic expression of interleukin 7 receptor on T cells, macrophages, and dendritic cells. Treatment of recombinant IL7 induced expansion of effector CD8 T cells along with pro-inflammatory activation of macrophages and dendritic cells. Spatial transcriptomic data revealed strengthen of anti-tumoral interactions between macrophages and T cells by IL7 treatment. Altogether, our results suggest that IL7 therapy is applicable to a broad range of cancer patients.

Therapeutic angiogenesis represents a promising avenue to revascularize the ischemic heart. Its limited success is partly due to our poor understanding of the cardiac stroma, specifically mural cells, and their response to ischemic injury. Here, we combine single-cell and positional transcriptomics to assess the behaviour of mural cells within the healing heart. In response to myocardial infarction, mural cells adopt an altered state closely associated with the infarct and retain a distinct lineage from fibroblasts. This response is concurrent with vascular rarefaction and reduced coverage by mural cells. Positional transcriptomics reveal that the infarcted heart is governed by regional-dependent and temporally regulated programs. While the remote zone acts as an important source of pro-angiogenic signals, the infarct zone is accentuated by chronic activation of anti-angiogenic, pro-fibrotic, and inflammatory cues. Together, our work unveils the spatiotemporal programs underlying cardiac repair and establishes an association between vascular deterioration and mural cell dysfunction.

To prevent autoimmunity, thymocytes expressing self-reactive T cell receptors (TCRs) are negatively selected, however, divergence into tolerogenic, agonist-selected lineages represent an alternative fate. As thymocyte development, selection, and lineage choices are dependent on spatial context and cell-to-cell interactions, we have performed Cellular Indexing of Transcriptomes and Epitopes by sequencing (CITE-seq) and spatial transcriptomics on paediatric human thymu​​s. Thymocytes expressing markers of strong TCR signalling diverged from the conventional developmental trajectory prior to CD4+ lineage commitment, while markers of different agonist cell populations (CD8αα(I), CD8αα(II), T(agonist), Treg(diff) and Treg) exhibited variable timing of induction. Expression profiles of chemokines and co-stimulatory molecules, together with spatial localization, supported that dendritic cells, B cells, and stromal cells contribute to agonist selection, with different subsets influencing thymocytes at specific developmental stages within distinct spatial niches. Understanding factors influencing agonist T cells is needed to benefit from their immunoregulatory effects in clinical use.

Although melanoma is notorious for its high degree of heterogeneity and plasticity, the origin and magnitude of cell state diversity remains poorly understood. Equally, it is not known whether melanoma growth and metastatic dissemination are supported by overlapping or distinct melanoma subpopulations. By combining mouse genetics, unbiased lineage tracing and quantitative modelling, single-cell and spatial transcriptomics, we provide evidence of a hierarchical model of tumour growth that mirrors the cellular and molecular logic underlying embryonic neural crest cell fate specification and differentiation. Our findings indicate that tumorigenic competence is associated with a spatially localized perivascular niche environment, a phenotype acquired through a NOTCH3-dependent intercellular communication pathway established by endothelial cells. Consistent with a model in which only a fraction of melanoma cells is fated to fuel growth, temporal single-cell tracing of a population of melanoma cells harbouring a mesenchymal-like state revealed that these cells do not contribute to primary tumour growth but, instead, constitutes a pool of metastatic-initiating cells that can switch cell identity while disseminating to secondary organs. Our data provide a spatially and temporally resolved map of the diversity and trajectories of cancer cell states within the evolving melanoma ecosystem and suggest that the ability to support growth and metastasis are limited to distinct pools of melanoma cells. The observation that these phenotypic competencies can be dynamically acquired upon exposure to specific niche signals warrant the development of therapeutic strategies that interfere with the cancer cell reprogramming activity of such microenvironmental cues.

We performed the first integrative single-cell and spatial transcriptomic analysis on HPV-negative oral squamous cell carcinoma (OSCC) to comprehensively characterize tumor core (TC) and leading edge (LE) transcriptional architectures. We show that the TC and LE are characterized by unique transcriptional profiles, cellular compositions, and ligand-receptor interactions. We demonstrate that LE regions are conserved across multiple cancers while TC states are more tissue specific, highlighting the existence of common mechanisms underlying tumor progression and invasion. Additionally, we found our LE gene signature is associated with worse clinical outcomes while the TC gene signature is associated with improved prognosis across multiple cancer types. Finally, using an in silico modeling approach, we describe spatially-regulated patterns of cell development in OSCC that are predictably associated with drug response. Our work provides pan-cancer insights into TC and LE biology and a platform for data exploration (http://www.pboselab.ca/spatial_OSCC/) that can be foundational for developing novel targeted therapies.

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system characterised by myelin loss and progressive neurodegeneration. To better understand MS lesion initiation and progression, we generated spatial gene activity maps of white (WM) and grey matter (GM) MS lesions. In different MS lesion types, we detected novel transcriptional domains, including an identifiable rim around active WM lesions. These active lesion rims were characterised by changes in astrocytic, oligodendrocytic, and microglial gene activity. Furthermore, we identified three novel WM lesion trajectories, predicting how normal appearing WM could progress into WM lesions, with lesion rims, active lesion cores, and mixed active/inactive lesion cores as potential outcomes. Our findings offer new insights into MS lesion progression, and the dynamic molecular and cellular processes that underlie MS.

Triple negative breast cancer (TNBC) is an aggressive and clinically challenging subtype of breast cancer. TNBC disporportionately affects African-American (AA) women, but the biological basis of this disparity is not understood. To gain a better understanding of TNBC, particularly in AA patients, we applied spatial transcriptomics to thoroughly characterize gene expression and tissue architecture in TNBC. Our cohort consisted of 22 patients, 15 of whom were AA, and 7 who were Caucasian. We obtained 2 sections from each patient's tumor (except for patient 19) for a total of 43 samples.

Tumor heterogeneity is a major challenge for oncology drug discovery and development. Understanding of the spatial tumor landscape is key to identifying new targets and impactful model systems. Here, we test the utility of spatial transcriptomics (ST) for Oncology Discovery by profiling 40 tissue sections and 80,024 capture spots across a diverse set of tissue types, sample formats, and RNA capture chemistries. We verify the accuracy and fidelity of ST by leveraging matched pathology analysis that provide a ground truth for tissue section composition. We then use spatial data to demonstrate the capture of key tumor depth features, identifying hypoxia, necrosis, vasculature, and extracellular matrix variation. We also leverage spatial context to identify relative cell type locations showing the anti-correlation of tumor and immune cells in syngeneic cancer models. Lastly, we demonstrate target identification approaches in clinical pancreatic adenocarcinoma samples, highlighting tumor intrinsic biomarkers and paracrine signaling.

8 spatial RNA-seq experiments (10x Genomics Visium) and 5 single-cell RNA-seq experiments (10x Genomics Chromium) using high-grade serous ovarian carcinoma (HGSOC) samples obtained from the ovaries during the interval debulking surgery

Cellular plasticity is a hallmark of rare Claudin-low (CL) and metaplastic (MBC) breast cancer subtypes, with a documented overlap whose exact extent is yet unknown, and which are associated to resistance and poor survival. We used spatial transcriptomics to further characterise these plastic subtypes, respectively defined molecularly and histopathologically. We identified 3 putative CL tumours (CL-like) and 4 genomically unstable TNBC samples via molecular analyses, combined with 4 MBCs identified by a breast pathologist. High resolution images are available on Zenodo https://zenodo.org/records/20727406

The ischemic borderzone (BZ) is a geographically complex and biologically enigmatic interface separating poorly perfused infarct zones (IZ) from comparatively healthy remote zones (RZ).  BZ cellular and molecular mechanisms are not well understood because efforts to dissect it inevitably include RZ and IZ in uncontrolled proportions. Here, we use single-cell/nuclei RNA-sequencing, spatial transcriptomics, and multiplexed RNA fluorescence in situ hybridization (mFISH) to identify BZ cardiomyocytes (CMs) subsets. BZ1 (Nppa+Xirp2­-) forms a hundreds-of-microns-thick transitional layer adjacent to RZ, while BZ2 (Nppa+Xirp2­+) forms a tens-of-microns-thick layer that the IZ edge. BZ2 CMs have reduced CM cell contact; colocalize with matricellular-protein-expressing myofibroblasts; and upregulate focal adhesion-, sarcomere-, and cytoskeletal-genes.  Surprisingly, the transcriptional BZ emerges within an hour of injury and is inducible by non-ischemic fine-needle-trauma. We suggest that mechanical instability and “loss of neighbor” at the BZ edge are the dominant inducers of the BZ transcriptional response.

Liver metastases are associated with poor response to current pharmacological treatments, including immunotherapy. We describe a lentiviral vector (LV) platform to selectively engineer liver macrophages, including Kupffer cells and tumor-associated macrophages (TAMs), to deliver type I interferon (IFNα) to liver metastases. Gene-based IFNα delivery delays the growth of colorectal and pancreatic ductal adenocarcinoma liver metastases in mice. Response to IFNα is associated with TAM immune activation, enhanced MHC-II-restricted antigen presentation and reduced exhaustion of CD8+ T cells. Conversely, increased IL-10 signaling, expansion of Eomes CD4+ T cells, a cell type displaying features of type I regulatory T (Tr1) cells, and CTLA-4 expression are associated with resistance to therapy. Targeting regulatory T cell functions by combinatorial CTLA-4 immune checkpoint blockade and IFNα LV delivery expands tumor-reactive T cells, attaining complete response in most mice. These findings support a promising therapeutic strategy with feasible translation to patients with unmet medical need.

While regulatory T (Treg) cells are traditionally viewed as professional suppressors of antigen presenting and effector T cells in both autoimmunity and cancer, recent findings of distinct Treg functions in tissue maintenance suggest that their regulatory purview extends to a wider range of cells and is broader than previously assumed. To elucidate tumoral Treg “connectivity” to diverse tumor-supporting accessory cell types, we explored immediate early changes in their single cell transcriptomes upon punctual Treg depletion in experimental lung cancer and injury-induced inflammation. Prior to any notable T cell activation and inflammation, fibroblasts, endothelial and myeloid cells exhibited pronounced changes in their gene expression in both cancer and injury settings. Factor analysis revealed shared Treg-dependent gene programs, foremost, prominent upregulation of VEGF signaling-related genes upon Treg deprivation in either setting, as well as in Treg-poor vs Treg-rich human lung adenocarcinomas. Accordingly, punctual Treg depletion combined with short-term VEGF blockade showed markedly improved control of PD-1 blockade-resistant lung adenocarcinoma progression in mice compared to the corresponding monotherapies, highlighting a promising factor-based querying approach to elucidating novel rational combination treatments of solid organ cancers.

The spatial organization of cells within tissues is tightly linked to their biological function. Yet, methods to probe the entire transcriptome of multiple native tissue microenvironments at single cell resolution are lacking. Here, we introduce fragment-sequencing, a method that enables the transcriptomic characterization of single cells within spatially distinct tissue niches. Fragment-sequencing of the mouse metastatic liver revealed previously uncharacterized zonated genes and ligand-receptor interactions enriched in the different hepatic microenvironments and the metastatic niche.

Spatial transcriptomic analysis of murine FDL tendons following acute injury and repair to evaluate spatiotemporal programming of tendon healing

Aging results in changes in mammary gland cell proportions, gene expression, and chromatin accessibility. Cell types captured include epithelial, immune, and stromal cell types.

Spatial transcriptomic profiling of two replicates of Patient and two replicates of Patient-corrected bioengineered vascular grafts harvested at week 8 post-implantation.

Using liver metastases from 4 colorectal cancer patients (CRC-LM), we explored one receptor: EGFR whose signaling triggers cell proliferation and is exacerbated in many tumors.

Patients with Neurofibromatosis Type 1 (NF1) present with fracture pseudarthroses, though the exact mechanism underlying this abnormal healing remains unknown. Here, we performed spatial transcriptomics to spatially-define the molecular signatures across endochondral healing following fracture. Integrating single-cell sequencing of patient fracture-derived primary cells, our results provide a dynamic cellular context to the molecular dysregulation associated with somatic fracture healing defects in NF1.

Zhang D et al. · 2023 · Nature

Fibrosis is important pathogenesis in heart failure with preserved ejection fraction (HFpEF). We previously reported that the overexpression of cardiac transcription factors, Mef2c/Gata4/Tbx5/Hand2 (MGTH) could directly reprogram cardiac fibroblasts (CFs) into induced CMs (iCMs) and reduce fibrosis. Here we show that in vivo cardiac reprogramming generated iCMs from resident CFs, improved cardiac function, and reversed fibrosis in HFpEF model using a novel transgenic mouse system. Visium revealed spatial information on changes in gene expression in HFpEF.

To investigate effects of IGF-1 on human-like coronary atherosclerosis we used high fat diet-fed Rapacz pigs with familial hypercholesterolemia (FH pigs). We used spatial transcriptomics (ST) analysis to identify global transcriptome changes in advanced plaque compartments and to obtain mechanistic insights into IGF-1 effects. IGF-1-injected FH pigs had 1.8-fold increase in total circulating IGF-1 levels compared to control. IGF-1 decreased relative coronary atheroma (data obtained by serial intravascular ultrasound) and lesion cross-sectional area (post-mortem histology). IGF-1 increased fibrous cap thickness, and reduced necrotic core size, macrophage content, and cell apoptosis, changes consistent with promotion of a stable plaque phenotype. ST analysis revealed that IGF-1 suppressed FOS/FOSB factors and gene expression of MMP9 and CXCL14 suggesting possible involvement of these molecules in IGF-1’s effect on atherosclerosis.

We designed a neural network-based computational method that learns transcriptome-to-space mapping and reconstructs 3D tissue organization by learning from scRNA-seq and spatial transcriptomic data.

Oral submucous fibrosis (OSF) is one of the most common precancerous malignant orders (PMO) with high rates exacerbating into oral squamous cell carcinoma (OSCC), mostly occurred in patients with chewing betel-nut habits in Southeast Asia and Pacific region. However, the spatial characteristics and heteogeneities of tumor microenvironment (TME) in OSF-associated OSCC still remains unclear. Here, we characterized the spatiotemporal changes of OSF-associated OSCC at different malignant states by performing 10x Visium Spatial Transcriptomics (ST) sequencing and airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI) analysis.

Spatially resolved transcriptomics has enabled precise genome-wide mRNA expression profiling within tissue sections. The performance of unbiased SRT methods targeting the polyA tail of mRNA, relies on the availability of specimens with high RNA quality. Moreover, the high cost of currently available SRT assays requires a careful sample screening process to increase the chance of obtaining high-quality data. Indeed, the upfront analysis of RNA quality can show considerable variability due to sample handling, storage, and/or intrinsic factors. We present RNA-Rescue Spatial Transcriptomics (RRST), an SRT workflow designed to improve mRNA recovery from fresh frozen specimens with moderate to low RNA quality. First, we provide a benchmark of RRST against the standard Visium spatial gene expression protocol on high RNA quality samples represented by mouse brain and prostate cancer samples. Then, we demonstrate the RRST protocol on tissue sections collected from five challenging tissue types, including: human lung, colon, small intestine, pediatric brain tumor, and mouse bone/cartilage. In total, we analyzed 52 tissue sections and our results demonstrate that RRST is a versatile, powerful, and reproducible protocol for FF specimens of different qualities and origins.

Tissue regeneration is orchestrated by macrophages that clear damaged cells and promote regenerative inflammation. How macrophages spatially adapt and diversify their functions to support the architectural requirements of actively regenerating tissue remains unknown. In this study, we reconstructed the dynamic trajectories of myeloid cells isolated from acutely injured and early-stage dystrophic muscles. We identified divergent subsets of monocytes/macrophages and dendritic cells (DCs) and validated markers (e.g., GPNMB) and transcriptional regulators associated with defined functional states. In dystrophic muscle, specialized repair-associated subsets exhibited distinct macrophage diversity and reduced DC heterogeneity. Integrating spatial transcriptomics analyses with immunofluorescence uncovered the ordered distribution of subpopulations and multilayered regenerative inflammation zones (RIZs) where distinct macrophage subsets are organized in functional zones around damaged myofibers supporting all phases of regeneration. Importantly, intermittent glucocorticoid treatment disrupted the RIZs. Our findings suggest that macrophage subtypes mediated the development of the highly ordered architecture of regenerative tissues, unveiling the principles of the structured yet dynamic nature of regenerative inflammation supporting effective tissue repair.

We attempted to determine histological localization of chemoresistant cancer subpopulation by performing spatial transcriptomics.

Adult neural stem cells (NSCs) contribute to lifelong brain plasticity. In the adult mouse ventricular-subventricular zone, NSCs are heterogeneous and, depending on their location in the niche, give rise to different subtypes of olfactory bulb (OB) interneurons. Here we show that multiple regionally-distinct NSCs, including domains that are usually quiescent, are recruited on different gestation days during pregnancy. Synchronized activation of these adult NSC pools generates transient waves of short-lived OB interneurons, especially in layers with less neurogenesis under homeostasis. Using spatial transcriptomics, we identify molecular markers of pregnancy-associated interneurons, and show that some subsets are temporarily needed for own pup recognition. Thus, pregnancy triggers transient, yet behaviorally-relevant neurogenesis, highlighting the physiological relevance of adult stem cell heterogeneity.

Recent advances in spatial transcriptomics (ST) enable gene expression measurements from a tissue sample while retaining its spatial context. This technology enables unprecedented in situ resolution of the regulatory pathways that underlie the heterogeneity in the tumor and its microenvironment (TME). The direct characterization of cellular co-localization with spatial technologies facilities quantification of the molecular changes resulting from direct cell-cell interaction, as occurs in tumor-immune interactions. We present SpaceMarkers, a novel bioinformatics algorithm to infer molecular changes from cell-cell interaction from latent space analysis of ST data. We apply this approach to infer molecular changes from tumor-immune interactions in Visium spatial transcriptomics data of metastasis, invasive and precursor lesions, and immunotherapy treatment. Further transfer learning in matched scRNA-seq data enabled further quantification of the specific cell types in which SpaceMarkers are enriched. Altogether, SpaceMarkers can identify the location and context-specific molecular interactions within the TME from ST data.

To investigate the celluar heterogeneity of ETMR and the role of pericytes in the tumor microenvironment, we performed single-cell RNA sequencing of about 140,000 cells from primary human and murine ETMR as well as from 2D ETMR cultures and 3D models of ETMR-harboring forebrain organoids. We also analysed 3 ETMR human samples by spatial transcriptomics.

Traumatic brain injury leads to a highly orchestrated immune- and glial cell response partially responsible for long-lasting disability and the development of secondary neurodegenerative diseases. A holistic understanding of the mechanisms controlling the responses of specific cell types and their crosstalk is required to develop an efficient strategy for better regeneration. Here, we combined spatial and single-cell transcriptomics to chart the transcriptomic signature of the injured murine cerebral cortex, and identified specific states of astrocytes, microglia, and oligodendrocyte precursor cells contributing to this signature. Interestingly, these cellular populations share a large fraction of injury-regulated genes, including inflammatory programs downstream of the innate immune-associated pathways Cxcr3 and Tlr1/2. Systemic manipulation of these pathways decreased the reactivity state of glial cells associated with poor regeneration. The functional relevance of the newly discovered shared signature of glial cells highlights the importance of our resource enabling comprehensive analysis of early events after brain injury.

Venezuelan equine encephalitis virus (VEEV) is a neurotropic alphavirus that causes neurological disease in both humans and equine. In this study we paired spatial transcriptomics and a mouse model of VEEV to generate a transcriptomic profile of infected or control brains at 6 days post infection. We identified regionally distinct myeloid and lymphocyte populations, contributing to our understanding of the neuroinflammation caused by VEEV.

Acute kidney injury (AKI) is a major health burden in the United States. Macrophages have been shown to mediate AKI in murine models. Murine kidneys contain multiple subpopulations of kidney resident macrophages (KRM) that are transcriptionally and spatially distinct. We hypothesized the human kidney contains orthologous KRM subpopulations, both transcriptionally and spatially. We utilized kidney sections from donors diagnosed with mild to moderate AKI in order to increase the translatability of murine research to clinical settings. We used spatial transcriptomics and single cell RNA sequencing to identify five distinct human KRM subpopulations. Using the AddModuleScore function in Seurat, we were able to compare the murine KRM transcriptional profiles from pre and post-AKI to the human KRM subpopulations. As a result, we identified four  orthologous to known murine KRM subpopulations. The remaining population was identified in the kidney cortex and expresses a profile similar to activate microglia, the resident macrophage population in the brain. Again, we used AddModuleScore to determine a set of marker genes that will allow for the identification of KRM subsets across species and injury.

To reveal the spatial distribution and the difference gene expression pattern of cancer cells in colorectal cancer, Visium spatial transcriptomics of four CRC patients was applied

The Illumina sequencing systems demonstrate high efficiency and power and remain the most popular platforms. Platforms with similar throughput and quality profiles but lower costs are under intensive development. In this study, we compared two platforms Illumina NextSeq 2000 and GeneMind Genolab M for 10x Genomics Visium spatial transcriptomics.

The transcription factor Gata3 is essential both for CD4+ T cell development in the thymus and for the differentiation of Th2 cells, which mediate responses against extracellular parasites and contribute to asthma and allergies. Here we report that the transcription factor Zfp281, in part redundantly with its paralog Zfp148, cooperates with Gata3 to promote CD4+ T cell development and Th2 cell differentiation. Disruption of both factors in T cells resulted in reduced numbers of spleen CD4+ T cells. Additionally, we show that Zfp281 interacts with Gata3, and that Zfp281 binds to Th2 cytokine loci in Th2 cells. Finally, we found that Zfp148 and Zfp281 promote Th2 cytokine expression. During airway inflammation, Zfp148/281-deficient CD4+ T cells failed to express Th2 cytokines, despite normal expression of Gata3. Altogether our data identify Zfp148 and Zfp281 as essential for enabling Gata3 functions in both CD4+ T cell development and Th2 function.

To unbiasedly characterize the spatial transcriptomics landscape of murine colorectal cancer initiation and progression, we performed a time-series spatial transcriptional analysis of total colonic tissue during the course of azoxymethane (AOM)-dextran sodium sulfate (DSS) induced colorectal cancer from mice receiving standard (chow) diet. Additionally, to understand the role of LXR activation during AOM-DSS tumorigenesis, we also collected colonic tissues from mice fed with GW3965 diet.

To unbiasedly characterize the spatial transcriptomics landscape of murine small intestine damage and repair, we performed a time-series spatial transcriptional analysis of total small intestinal tissue during the course of irradiation damage from mice receiving standard diet. Additionally, to understand the role of LXR activation during damage and repair, we also collected small intestine tissues from mice fed with GW3965 diet.

Acute kidney injury (AKI) is a major health burden in the United States. Macrophages have been shown to mediate AKI in murine models. Murine kidneys contain multiple subpopulations of kidney resident macrophages (KRM) that are transcriptionally and spatially distinct. We hypothesized the human kidney contains orthologous KRM subpopulations, both transcriptionally and spatially. We utilized kidney sections from donors diagnosed with mild to moderate AKI in order to increase the translatability of murine research to clinical settings.

ADAR1 is thought to be an immune suppressor maintaining self-tolerance to endogenous nucleic acids. Lack of ADAR1 results in MDA5 (Ifih1) activation and MDA5 deletion rescues ADAR1 null embryonic lethality. We generated liver specific ADAR1; MDA5 double KO mice and performed high throughput sequencing to investigate hepatic inflammation in these mice. Spatial transcriptomics (Visium, 10x Genomics) was performed on FFPE mice liver tissues. Constructed libraries were sequenced on the Novaseq 6000 platform. Over 250 million pairs of mappable reads for each sample were obtained.

Fibroblasts are key orchestrators of inflammation. Little is known whether these cells change phenotype during resolution of inflammation. We adopted a method to visualise fibroblast activation during inflammation in humans in vivo, which is based on a fibroblast activation protein (FAP) tracer detected by positron emission tomography (PET). While tracer accumulation was high in active arthritis, it decreased significantly after TNF- and IL-17A inhibition. Biopsy-based scRNA-seq analyses in experimental arthritis demonstrated that FAP signal reduction reflected a phenotypic switch from pro-inflammatory MMP3+/IL6+ fibroblasts (high FAP internalisation) to pro-resolving CD200+DKK3+ fibroblasts (low FAP internalisation). Spatial transcriptomics of human joints revealed that pro-resolving niches of CD200+DKK3+ fibroblasts clustered with innate lymphoid cells (ILC)2, whereas MMP3+/IL6+ fibroblasts were co-localised with inflammatory immune cells. CD200+DKK3+ fibroblasts stabilised the ILC2 phenotype and induced resolution of arthritis via CD200/CD200R1 pathway. Taken together, these data suggest a dynamic molecular regulation of the mesenchymal compartment during resolution of inflammation.

4T1 tumors, 4 weeks after implantation were excised and analyzed using the 10X Visium technology.

Hashimoto's thyroiditis and papillary thyroid cancer are the most common thyroid disorders. We used spatial transcriptome sequencing (ST-seq) to investigate their potential relationship.

Rheumatoid arthritis (RA) is the most common systemic autoimmune disease. T helper 17 (Th17) cells are found in the inflamed synovium in RA and believed to play a pathogenic role. However, IL-17 targeted interventions have shown limited efficacy in established RA. Inflammation can induce Th17 transdifferentiation into IL-17 negative Th1 or Tr1 like exTh17. To assess the potential phenotype and role of exTh17 in inflammatory arthritis, we performed Th17 fate mapping studies in the SKG mouse model of RA. We generated triTh17-SKG (IL-17Cre.IfngYFP.Il10eGFP.R26tdTomfl.Zap70SKG) mice and leveraged them to show that in arthritic mice synovial Th17 transdifferentiate into IFNγ- and IL-10- exTh17 which become the most prominent CD4 population in chronic arthritis. These exTh17 cells are more arthritogenic than Th17, and able to sustain arthritis that is IL-17 independent but enriched with IL-6 and TNF, two known RA-promoting cytokines. Synovial exTh17 present a unique gene signature including upregulation of CD44 and S1PR4 that has correlates in the profile of CD4 T cells found in human RA synovium. We further demonstrate that a crosstalk with synoviocytes and S1P signaling promote Th17-exTh17 conversion and that CD44 – another known target for RA- is necessary for the arthritogenic effect of exTh17. Our study suggests that the synoviocyte expansion which occurs during RA progression can drive progressive conversion of Th17 into exTh17, which in turn sustain inflammation that has hallmarks of human established RA.

We present a spatial omics approach that merges and expands the capabilities of independently performedin situassays on a single tissue section. Our spatial multimodal analysis combines histology, mass spectrometry imaging, and spatial transcriptomics to facilitate precise measurements of mRNA transcripts and low-molecular weight metabolites across tissue regions. We demonstrate the potential of our method using murine and human brain samples in the context of dopamine and Parkinson’s disease.

We monitored lung fibrosis formation and resolution in young and old mice by generating a series of spatial transcriptomics datasets using the 10x Genomics Visium platform

Epithelial-to-Mesenchymal transition (EMT) regulates tumour initiation, progression, metastasis and resistance to anti-cancer therapy. Whereas great progress had recently been made in understanding the role and mechanisms that regulate EMT in cancer, no therapeutic strategy to pharmacologically target EMT had been identified so far. Here, we found that Netrin-1 is upregulated in a primary mouse model of skin squamous cell carcinoma (SCCs) presenting spontaneous EMT. Pharmacological inhibition of Netrin-1 by administrating NP137, an anti-Netrin-1 blocking monoclonal antibody currently used in clinical trials in human cancer, decreased the proportion EMT tumour cells in skin SCCs, as well as decreased the number of metastasis and increased the sensitivity of tumour cells to chemotherapy. Single-cell RNA-seq revealed the presence of different EMT states including epithelial, early and late hybrid EMT as well as fully EMT states in control SCCs. In contrast, administration of NP137 prevents the progression of cancer cells towards a late EMT state and sustains tumour epithelial states. ShRNA knockdown (KD) of Netrin-1 and its receptor Unc5b in EPCAM+ tumour cells inhibited EMT in vitro in the absence of stromal cells and regulated a common gene signature promoting tumour epithelial state and restricting EMT. To assess the relevance of these findings to human cancers, we treated mice transplanted with A549 human cancer cell line that undergoes EMT following TGF-b1 administration with NP137. Netrin-1 inhibition decreased EMT in A549 cells in vivo. Altogether, our results identify a new pharmacological strategy to target EMT in cancer opening novel therapeutic interventions for anti-cancer therapy.

We identified five distinct functional subclusters of pancreatic cancer cells and six distinct cancer-associated fibroblast subclusters. We deeply profiled their characteristics, and we found that these subclusters successfully deconvoluted most of the features suggested in bulk transcriptome analysis of pancreatic cancer. Among those subclusters, we identified a novel cancer cell subcluster, Ep_VGLL1, showing intermediate characteristics between the extremities of basal-like and classical dichotomy, despite its prognostic value. Molecular features of Ep_VGLL1 suggest its transitional properties between basal-like and classical subtypes, which is strongly supported by spatial transcriptome data.

The tumor evolution model posits that malignant transformation is preceded by randomly distributed driver mutations in cancer genes, which cause clonal expansions in phenotypically normal tissues. Although clonal expansions can remodel entire tissues1-3, the mechanisms behind why only a small number of clones transform into malignant tumors remain enigmatic. Here, we develop an in vivo single-cell CRISPR strategy to systematically investigate tissue-wide clonal dynamics of the 150 most frequently mutated squamous cell carcinoma genes. We couple ultrasound-guided in utero lentiviral microinjections, single-cell RNA sequencing and guide capture to longitudinally monitor clonal expansions and document their underlying gene programs at single-cell transcriptomic resolution. We uncover a TNF-α signaling module, dependent on TNF receptor 1 and involving macrophages, that acts as a generalizable driver of clonal expansions in epithelial tissues. Conversely, during tumorigenesis, the TNF-α signaling module is downregulated. Instead, we identify a subpopulation of invasive cancer cells that switch to an autocrine TNF-α gene program, associated with epithelial-mesenchymal transition. Finally, we provide in vivo evidence that the autocrine TNF-α gene program is sufficient to mediate invasive properties and show that the TNF-α signature correlates with shorter overall survival in human squamous cell carcinoma patients. Collectively, our study demonstrates the power of applying in vivo single-cell CRISPR screening to mammalian tissues, unveils distinct TNF-α programs in tumor evolution and highlights the importance of understanding the relationship between clonal expansions in epithelia and tumorigenesis.

Spatial transcriptomics (ST) technologies enable the mapping of gene expression to specific regions within tissues. However, current ST platforms present inherent trade-offs between resolution and throughput, which cannot be entirely addressed by a single technology. To unravel the spatiotemporal landscape of gene expression and cellular interactions during kidney injury and repair, we employed an integrated approach combining Xenium's high-resolution in situ sequencing with Visium's whole-transcriptome spatial profiling.

The neoadjuvant immune checkpoint blockade therapy only benefits a limited fraction of glioblastoma multiforme (GBM) patients. Thus, targeting other immunomodulators on myeloid cells is an attractive therapeutic option. Here, we performed single-cell RNA sequencing and spatial transcriptomics of GBM patients treated with neoadjuvant anti-PD-1 therapy. We identified unique monocyte-derived tumor-associated macrophage (TAM) subpopulations with functional plasticity that highly expressed the immunosuppressive SIGLEC9 gene and preferentially accumulated in the non-responders to anti-PD-1 treatment. Deletion of Siglece (murine homologue) resulted in significantly restrained tumor development and prolonged survival in mouse models. Mechanistically, targeting Siglece directly activated both CD4+ T cells and CD8+ T cells through antigen presentation, secreted chemokines and co-stimulatory factor interactions. Furthermore, Siglece deletion synergized with anti-PD-1/PD-L1 treatment to improve antitumor efficacy. Our data demonstrated that Siglec-9 is an immune checkpoint molecule on macrophages that can be targeted to enhance anti-PD-1/PD-L1 therapeutic efficacy for GBM treatment.

Wound healing is orchestrated by a spatial and temporal network of intercellular communication between epithelial cells, the stromal compartment, and the immune system. Our scRNA-seq analysis of Hgfac WT and KO wounds reveals that Aldh1a3 is downstream of the HGFAC system and Aldh1a3 is highly upregulated in wound-asociated epithelial (WAE) cells in responce to endoscopic wounding, suggesting WAE cells can potentially secrete retinoic acid into wound bed. To dissect the healing responce in the intestinal mucosa, we peformed spatial transcriptomics analysis.

Spatial transcriptomics (ST) is an innovative technology that holds tremendous potential for transforming the field of tissue biology research. By simultaneously capturing multiple types of spatial data, including gene expression values, spatial distance information, and tissue morphology, ST enables a comprehensive understanding of biological samples. However, the effective integration of these diverse data types remains a challenge. In this study, we present stLearn, a collection of three computational-statistical algorithms specifically designed to exploit the combined power of gene expression, spatial distance, and tissue morphology data. Our aim is to unlock novel insights into tissue maintenance, development, and disease. The first algorithm, known as pseudo-time-space (PSTS), employs a spatial-graph-based approach to uncover the spatial relationships between cells' transcriptional states in dynamic tissue contexts. To demonstrate the effectiveness of stLearn, we utilize traumatic brain injury datasets to investigate the spatio-temporal dynamics of microglia activation. By applying the PSTS algorithm to a well-established mouse model of acquired brain injury, we successfully reconstruct the spatial trajectory of microglia activation following insult, thereby validating this key component of stLearn.

The liver is a central organ for physiology and metabolism, with hepatocytes being the main cell type responsible for most of its functions. Several previous studies investigated the cell types involved in tissue homeostasis and regeneration, however the mechanisms underlying post-natal liver growth and establishment of the mature hepatocyte phenotypes remain to be fully understood. Moreover, genetic modification of hepatocytes is emerging as a promising therapeutic approach, particularly for genetic diseases of the coagulation system and hepatic metabolism. Here, we investigate liver tissue dynamics in mice during post-natal growth and turnover in adulthood, by spatial transcriptomics, clonal analysis, and lineage tracing. We observe progressive establishment of metabolic zonation of hepatocytes and that only a fraction of hepatocytes proliferates in the newborn liver, generating most of the adult tissue. We assess the impact of these changes on both in vivo liver gene transfer and gene editing. We show that the age at treatment affects both the efficiency and lobule distribution of lentiviral vector-mediated gene transfer, and that preferential targeting of the more proliferating hepatocytes allows expansion of the genetically modified liver area. Overall, our findings provide new insights into the spatio-temporal dynamics of the liver during post-natal growth and hepatocyte heterogeneity, with broad implications for liver biology and therapeutic applications.

Glioma contains malignant cells in diverse states. Here, we combine spatial transcriptomics with novel computational approaches to uncover the organization of glioma cellular states. We find three prominent modes of organization. First, cells in any given state tend to be spatially clustered, with local environments that are each enriched with one major cellular state. Second, specific pairs of states preferentially reside in proximity across multiple scales. Third, the pairwise interactions that we detect collectively define a global architecture composed of five layers. Hypoxia appears to drive this 5-layered organization, as it is associated with a long-range organization that extends from the hypoxic core to the infiltrative edge of the tumor. Accordingly, tumor regions distant from any hypoxic foci are less organized. In summary, we provide a conceptual framework for the organization of gliomas and highlight the role of hypoxia as a potential long-range tissue organizer.

We designed a Nextflow DSL2-based pipeline, Spatial Transcriptomics Quantification (STQ), for simultaneous processing of 10x Genomics Visium spatial transcriptomics data and a matched hematoxylin and eosin (H&E)-stained whole slide image (WSI), optimized for Patient-Derived Xenograft (PDX) cancer specimens. Our pipeline enables the classification of sequenced transcripts for deconvolving the mouse and human species and mapping the transcripts to reference transcriptomes. We align the H&E WSI with the spatial layout of the Visium slide and generate imaging and quantitative morphology features for each Visium spot. The pipeline design enables multiple analysis workflows, including single or dual reference genomes input and stand-alone image analysis. We show the utility of our pipeline on a dataset from Visium profiling of four melanoma PDX samples. The clustering of Visium spots and clustering of H&E imaging features reveal similar patterns arising from the two data modalities.

We designed an ex vivo system to culture tissue explants from lymphoma tissue. To characterize the spatial and molecular structure of human lymphomoids and their tissue of origin, we performed spatial transcriptomics analyses on original tissues and lymphomoids obtained from 2 patients using the 10x Genomics Visium technology.

The thymus is essential for establishing adaptive immunity yet undergoes age-related involution that leads to compromised immune responsiveness. The thymus is also extremely sensitive to acute insult and although capable of regeneration, this capacity declines with age for unknown reasons. We applied single-cell and spatial transcriptomics, lineage-tracing and advanced imaging to define age-related changes in non-hematopoietic stromal cells and discovered the emergence of two atypical thymic epithelial cell (TEC) states. These age-associated (aa)TECs formed high-density peri-medullary epithelial clusters that were devoid of thymocytes; an accretion of non-productive thymic tissue that worsened with age, exhibited features of epithelial-to-mesenchymal transition (EMT), and was associated with downregulation of FOXN1. Interaction analysis revealed that the emergence of aaTEC drew tonic signals from other functional TEC populations at baseline acting as a sink for TEC growth factors. Following acute injury, aaTEC expanded substantially, further perturbing trophic regeneration pathways and correlating with defective repair of the involuted thymus. These findings therefore define a unique feature of thymic involution linked to immune aging and could have implications for developing immune boosting therapies in older individuals.

To understand the role of hypoxia in metastatic progression, we sought to spatially map gene expression in hypoxic cells compared with cells that migrated to oxygenated tumor regions. We adapted the Visium spatial transcriptomics protocol to perform concurrent transcriptional profiling and fluorescent imaging of our hypoxia fate-mapping system.

Primary sclerosing cholangitis (PSC) is a rare liver disease characterized by chronic inflammation and irreparable damage to the bile ducts. Due to a limited understanding of the underlying pathogenesis of disease, there remains a paucity of treatment options. As such, we sequenced healthy and diseased livers to compare the activity, interactions, and localization of immune and non-immune cells. This revealed that outside PSC scar regions, hepatocytes are transitioning to bile duct cells, whereas within the scars, there is an accumulation of immune cells. Of these cells, macrophages that typically contribute to tissue repair were enriched in immunoregulatory genes and were less responsive to stimulation. These cells are likely involved in maintaining hepatic inflammation and could be targeted in novel therapeutic development.

The developing brain has a complex and well-organized anatomical structure comprising different types of neural and non-neural cells. Stem cells, progenitors, and newborn neurons tightly interact with their neighbouring cells and tissue microenvironment, and this intricate interplay ultimately shapes the output of neurogenesis. Given the relevance of spatial cues during brain development, we acknowledge the necessity for a transcriptomics atlas within the tissue context accessible to the neurodevelopmental community. To fulfil this need, we offer an open-access spatial gene expression browser of the embryonic mouse brain at the peak of neurogenesis. Using 10x Visium technology, we generated spatially-resolved RNAseq data from E13.5 embryonic brain sections. Unsupervised clustering reliably defined specific cell type populations of diverse lineages and maturational states. Differential expression analysis revealed unique transcriptional signatures across specific embryonic brain areas, uncovering novel features inherent to particular anatomical domains. Furthermore, we integrated single-cell RNAseq data from E13.5 mouse brains into our Spatial Transcriptomics data, adding tissue context to single-cell resolution. In summary, we provide a valuable tool that enables the exploration and discovery of unforeseen molecular players involved in neurogenesis, particularly in the crosstalk between different cell types.

Background. Using proteomics, we aimed to reveal molecular types of humanatherosclerotic lesions and study their associations with histology, imaging andcardiovascular outcomes. Methods. 219 carotid endarterectomy samples were procured from 120 patients. A sequential protein extraction protocol was employed in conjunction with multiplexed, discovery proteomics. To focus on extracellular proteins, parallel reaction monitoring was employed for targeted proteomics. Proteomic signatures were integrated with bulk, single-cell, and spatial RNA-sequencing data, and validated in 200 patients from the Athero-Express Biobank study. Results. This extensive proteomics analysis identified plaque inflammation and calcification signatures, which were inversely correlated and validated using targeted proteomics. The inflammation signature was characterized by the presence of neutrophil-derived proteins, such as S100A8/9 and myeloperoxidase, while the calcification signature included fetuin-A, osteopontin, and gamma-carboxylated proteins. The proteomics data also revealed sex differences in atherosclerosis, with large-aggregating proteoglycans versican and aggrecan being more abundant in females and exhibiting an inverse correlation with estradiol levels. The integration of RNA sequencing data attributed the inflammation signature predominantly to neutrophils and macrophages, and the calcification and sex signatures to smooth muscle cells, except for certain plasma proteins that were not expressed but retained in plaques, such as fetuin-A. Dimensionality reduction and machine learning techniques were applied to identify four distinct plaque phenotypes based on proteomics data. A protein signature of 4 key proteins (calponin, protein C, serpin H1, and versican) predicted future cardiovascular mortality with an area under the curve of 75% and 67.5% in the discovery and validation cohort, respectively, surpassing the prognostic performance of imaging and histology. Conclusions. Plaque proteomics redefined clinically relevant 55 patient groups with distinct outcomes, identifying subgroups of male and female patients with elevated risk of future cardiovascular events.

The diversity of cell-cell interactions in different regions of a tumor reflects the functional heterogeneity of cancer, which poses challenges in early diagnosis, selection of treatment strategies, and prognosis of breast cancer. Cancer cells interact with each other to form different morphological structures in the tumor and stromal host cells via integrins. The objective of this study was to characterize the morphological and spatial heterogeneity of primary breast tumors in the context of expression profiles of integrins and their ligands. We studied spatial transcriptomics using the 10X Visium approach and the NICHES algorithm to map ligand-receptor signaling pathways and visualize the heterogeneity of signaling archetypes in tumor clusters. Cluster analysis of the expression profiles of tumor spots from the samples indicated pronounced inter-tumoral heterogeneity. Integrin-ligand functional clusters were associated with intratumoral heterogeneity, which was manifested by the presence of several morphological loci as observed in histological tumor samples. Inter-tumoral heterogeneity was manifested by a different number of functional clusters, ranging from 2 to 9 for each tumor sample. The main characteristic of these clusters was the significant predominance of non-complementary integrin subunits. Of the 42 functional integrin-ligand pairs in 21 clusters of five samples, 41 pairs occurred only once. The exception was the LAMA5-ITGB4 pair, which was detected in two clusters of different samples. The spatial heterogeneity of integrin-ligand expression clusters in breast cancer contributes significantly to the functional heterogeneity of the tumor, which sets the stage for many scenarios of parenchymatous-stromal relationships, some of which may be effective in the emergence of metastasizing tumor seed cells. The intra- and inter-tumoral spatio-functional heterogeneity of the tumor tissue that we discovered may largely explain why it is difficult to achieve success in most patients with breast cancer using any therapeutic strategy targeting one molecule of the vast array, regardless of the importance of its pathogenetic significance.

We perform bulk RNA sequencing, tumor/normal DNA sequencing, and spatial transcriptomics on an initial discovery cohort of eleven glioma samples (comprising oligodendrogliomas, astrocytomas, one diffuse midline glioma, and glioblastomas) to identify both commonalities and distinct characteristics within the tumor microenvironment. Six additional high-grade IDH wild-type, EGFR positive glioblastomas are analyzed to validate subclonal somatic aneuploidy and copy number alterations associated with extrachromosomal DNA double-minutes. As part of the standard spatial transcriptomic analysis, we develop an integrated analysis framework combining germline/tumor exomes, bulk RNA-seq, and spatial transcriptomics to identify loss of heterozygosity by a hidden Markov model for segmenting consecutively expressed SNPs. In the discovery cohort, we identify focally amplified ecDNA in four of the eleven cases, with subclonal tumor heterogeneity present in two EGFR-amplified grade IV glioblastomas. In a TP53-mutated glioblastoma, we detect a subclone with EGFR amplification on ecDNA coupled to chromosome 17 LOH. To evaluate the impact of spatial subclonal chromosomal alterations on the p53/EGFR axis, we examine six additional EGFR positive gliomas, identifying MDM2/MDM4 ecDNA subclones in two samples. The spatial DNA heterogeneity of EGFR and p53 inactivation underscores the role of ecDNA in enabling rapid oncogene amplification and enhancing tumor adaptability under selective pressure.

The tumor microenvironment (TME) and its multifaceted interactions with cancer cells are major targets for cancer treatment. Single-cell technologies have brought major insights into the TME, but the resulting complexity frequently precludes conclusions on function. Therefore, we combined single-cell RNA sequencing and spatial transcriptomic data to explore the relationship between different cancer-associated fibroblast (CAF) populations and immune cell exclusion in breast tumors. Our data show for the first time the degree of spatial organization of different CAF populations in breast cancer. We found that IL-iCAFs, Detox-iCAFs, and IFNγ-iCAFs tended to cluster together, while Wound-myCAFs, TGFb-myCAFs, and ECM-myCAFs formed another group that overlapped with elevated TGF-b signaling. Differential gene expression analysis of areas with CD8+ T-cell infiltration/exclusion within the TGF-b signaling-rich zones identified elastin microfibrillar interface protein 1 (EMILIN1) as a top modulated gene. EMILIN1, a TGF-b inhibitor, was upregulated in IFNγ-iCAFs directly modulating TGFb immunosuppressive function. Histological analysis of 74 breast cancer samples confirmed that high EMILIN-1 expression in the tumor margins was related to high CD8+ T-cell infiltration, consistent with our spatial gene expression analysis. High EMILIN-1 expression was also associated with better prognosis of patients with breast cancer, underscoring its functional significance for the recruitment of cytotoxic T cells into the tumor area. In conclusion, our data show that correlating TGF-b signaling to a CAF subpopulation is not enough because proteins with TGF-b-modulating activity originating from other CAF subpopulations can alter its activity. Therefore, therapeutic targeting should remain focused on biological processes rather than on specific CAF subtypes.

Prior research has demonstrated genome-wide transcriptional changes related to fear and anxiety across species, often focusing on individual brain regions or cell types. However, the extent of gene expression differences across brain regions and how these changes interact at the level of transcriptional connectivity remains unclear. To address this, we performed spatial transcriptomics RNAseq analyses in an auditory threat conditioning paradigm in mice. We generated a spatial transcriptomic atlas of a coronal mouse brain section covering cortical and subcortical regions, corresponding to histologically defined regions. Our finding revealed widespread transcriptional responses across all brain regions examined, particularly in the medial and lateral habenula, and the choroid plexus. Network analyses highlighted altered transcriptional connectivity between cortical and subcortical regions, emphasizing the role of steroidogenic factor 1. These results provide new insights into the transcriptional networks involved in auditory threat conditioning, enhancing our understanding of molecular and neural mechanisms underlying fear and anxiety disorders.

Two different coronary artery samples with erosion plaques were selected from female heterozygous for the deletion BGN. Hybridization of target RNA-specific probes was used to visualize the spatial distribution of mutants. After determine the leison with clonality and non-clonal SMC proliferation, spatial transcriptomics was used to identify differentially expressed transcripts within clonal and non-clonal regions.

Sarcoidosis is a multisystemic disease characterized by non-caseating granuloma infiltrating various organs. The form with symptomatic muscular involvement is called muscular sarcoidosis. The impact of immune cells composing the granuloma on the skeletal muscle is misunderstood. Here, we investigated the granuloma-skeletal muscle interactions through spatial transcriptomics. Five major transcriptomic clusters corresponding to perigranuloma, granuloma, and three successive muscle tissue areas (proximal, intermediate and distal) around the granuloma were identified. Analyses revealed upregulated pathways in the granuloma corresponding to the activation of T-lymphocytes and monocytes/macrophages cytokines and upregulation of extracellular matrix signatures and induction of the TGF-β signaling in the perigranuloma. Comparison between proximal and distal muscles to the granuloma revealed an inverse correlation between distance to the granuloma and upregulation of cellular response to interferon-γ/α, TNF-α, IL-1,4,6, fibroblast proliferation, epithelial to mesenchymal cell transition and downregulation of muscle gene expression. These data shed light on the intercommunications between granulomas and the muscle tissue and provides pathophysiological mechanisms by showing that granuloma immune-cells have a direct impact on proximal muscle tissue by promoting its progressive replacement by fibrosis via the expression of pro-inflammatory and pro-fibrosing signatures. These data could possibly explain the evolution towards a state of disability for some patients.

Squamous cell carcinoma arising from mature teratoma (SCC-MT) is one of the rare ovarian malignancies. Therefore, the molecular background of SCC-MT remains largely unelucidated. In this study, we performed the spatial transcriptomics for SCC-MT.

Embryonic mouse diaphragm is a primary model for studying myogenesis and neuro-muscular synaptogenesis, both of which represent processes regulated by spatially organized genetic programs of myonuclei located in distinct myodomains. However, a spatial gene expression pattern of embryonic mouse diaphragm has not been reported. Here we provide spatially resolved gene expression data for horizontally sectioned embryonic mouse diaphragms at E14.5 and E18.5. These data reveal gene signatures for specific muscle regions with distinct maturity and fiber type composition, as well as for a central neuromuscular junction and a peripheral myotendinous junction compartments. Comparing spatial expression patterns of wild type mice with those of mouse mutants lacking either the skeletal muscle calcium channel CaV1.1 or b-catenin, reveals curtailed muscle development and dysregulated expression of genes potentially involved in NMJ formation. Altogether, these datasets provide a powerful recourse for further studies of muscle development and NMJ formation in the mouse embryo.

6 datasets

Peripheral afferent neurons terminate at the surfaces of tendons, yet their role after injury beyond nociceptive functions remain unclear. Using transgenic animal models, sensory neurons were found to sprout after Achilles tendon injury in domains of Nerve growth factor (NGF) expression. Conditional deletion of Ngf in either myeloid or mesenchymal cell types led to tendon repair defects – findings phenocopied by inactivation of TrkA (Tropomyosin receptor kinase A) using a knockin mouse model. We sought to identify the signals modulated with neural TrkA inhibition. A combination of single cell and spatial transcriptomic analysis was performed on the Achilles injury site of TrkA^F592A animals and compared them to TrkA^WT.

The mechanisms that guide Th2 cell differentiation in barrier tissues are unclear but important for the development of allergic asthma. Using temporal, spatial and single cell transcriptomic tracking of house dust mite (HDM) specific T cells, we describe the molecular pathways driving allergen-specific Th2 cells. Early Blimp-1 expression occurs in a subset of CD4 T cells in the lymph node prior to lung migration driven by IL-10 from allergen-specific T cells, but was not required for GATA3 upregulation. Instead, IL-2 via STAT5 was required to directly repress Bcl6 and Bach2 to support GATA3 and Blimp-1 upregulation. Loss of Blimp-1 during priming in the lymph node ablated the formation of Th2 cells that migrate to the lung, indicating early Blimp-1 promotes the population of Th2 cells with migratory capability. Spatial microniches of IL-2 in the lymph node discriminate and support these earliest Blimp-1+ migratory Th2 cells, demonstrating that lymph node localization is a primary driver of differentiation. Our findings illuminate the molecular pathways for inhaled allergens to promote Th2 cells and identify an early requirement for IL-2 mediated spatial microniches and allergen-driven IL-10 from responding T cells that drive allergic asthma.

The intestine is characterized by an environment where host requirements for efficient nutrient and water absorption are consequently paired with the requirement to establish and maintain tolerance to the outside environment. The organ is anatomically organized into the small intestine (SI) which specializes in nutrient absorption and the colon which specializes in water resorption. The transcriptional and cellular circuits that define intestinal regionalization and their robustness, adaptability, and resilience to changes in the local environment are not well characterized. Here, we generated a comprehensive survey of the spatial and cellular landscape of the murine intestine to demonstrate the steady state transcriptional landscape of the murine intestine is robust, adaptable, and resilient to perturbation. We characterized the transcriptional landscape of the full length of the intestine and show it is established independently of the microbiota and is not under circadian regulation. In the colon, these regional circuits were characterized by unique subsets of structural cells. Moreover, we identified a spatial adaptation to the microbiota in the colon characterized by the emergence of unique structural cell subsets including an enterocyte, fibroblast, and goblet cell, with the later two co-occurring in space. Employing a model of acute spatiotemporal damage allowed us to show the spatial landscape and adaptations we identified are both resilient to inflammation. Our results demonstrate that intestinal circuits are under host control and spatial adaptations in the steady state as well as in the process of recovery from tissue damage in the inflamed state are primarily characterized by changes to structural cell types such as epithelial and stromal cells.

Over half of BRAF-mutant melanoma patients with initial response to targeted therapy will recur with resistant disease. It is thought that resistance can arise from the ability of cells to enter and exit a slow cycling persister state, evade treatment with relative dormancy, and repopulate the tumor when reactivated. However, the expression states of persister and resistant cells, their spatial relationships in the tumor environment, and the evolutionary progression among these populations are not well understood. Using patient derived xenograft (PDX) models, we track melanoma evolution longitudinally from pre-treatment through maximum treatment response and tumor regrowth. We perform spatial transcriptomics (ST) to 1. define expression signatures within treatment-sensitive, persister, and re-emergent populations, 2. uncover fluctuating metabolic priorities as a hallmark of tumor evolution both across treatment time and geographically across tissue sections, and 3. identify specific genes and pathways within persister and resistant lineages as candidate resistance mechanisms, suggesting potential therapeutic targets. Our novel computational pipeline integrates ST data with deep learning imaging features derived from accompanying histopathological slides. We identify phenotypic states that correlate with the persister cell state, exploiting the juxtaposition of transcriptomic and histological features toward the goal of identifying clonal populations using imaging data alone. In summary, we provide insight into the dynamics of shifting expression state and lineage selection in melanoma during multiple stages of treatment with novel spatiotemporal resolution, defining an evolutionary roadmap to acquired resistance.

To investigate the spatial distribution of different cell types within the tumor microenvironment in PDAC, we performed Visium spatial transcriptomics (10X Genomics) on FFPE samples from five treatment-naïve PDAC patient tissues.

Primary sclerosing cholangitis (PSC) is a rare liver disease characterized by chronic inflammation and irreparable damage to the bile ducts. Due to a limited understanding of the underlying pathogenesis of disease, there remains a paucity of treatment options. As such, we sequenced healthy and diseased livers to compare the activity, interactions, and localization of immune and non-immune cells. This revealed that outside PSC scar regions, hepatocytes are transitioning to bile duct cells, whereas within the scars, there is an accumulation of immune cells. Of these cells, macrophages that typically contribute to tissue repair were enriched in immunoregulatory genes and were less responsive to stimulation. These cells are likely involved in maintaining hepatic inflammation and could be targeted in novel therapeutic development.

Hepatocellular carcinoma (HCC) is an inflammation-associated cancer arising from viral and non-viral etiologies. Expansion of suppressive myeloid cells is a hallmark of chronic inflammation and cancer, but their heterogeneity in HCC is not fully resolved and might underlie immunotherapy resistance in the steatohepatitis setting. Here, we present a high resolution atlas of hepatic innate immune cells from patients with HCC that unravels a steatohepatitis contexture characterized by influx of inflammatory and immunosuppressive myeloid cells. A discrete myeloid cell population identified by selective expression of TREM1 and CD163 expands in steatohepatitis-HCC. We refer to this population as TREM1+ regulatory myeloid cells (Mreg), as it potently suppresses T cell effector functions, highly expresses TGFB1 and IL13RA1 and localizes to HCC fibrotic lesions.

Liver zonation characterizes the separation of metabolic pathways along the lobules and is required for optimal hepatic function. Wnt signaling is a master regulator of spatial liver zonation. A perivenous-periportal Wnt activity gradient orchestrates metabolic zonation by activating genes in perivenous hepatocytes, while suppressing genes in their periportal counterparts. The understanding of liver gene zonation and zonation regulators in disease was limited. Non-alcoholic steatohepatitis (NASH) is a chronic liver disease characterized by fat accumulation, inflammation, and fibrosis. Here, we investigated the perturbation of liver gene zonation in a mouse NASH model by combination of spatial transcriptomics, bulk RNAseq and in situ hybridization. Wnt target genes represented a major subset of genes showing altered spatial expression in the NASH liver. The altered Wnt target gene expression level and zonation spatial pattern were in line with the upregulation of Wnt regulators and the augmentation of Wnt signaling. Particularly, we found that the Wnt activator Rspo3 expression was restricted to the perivenous zone in control livers, whereas expanded to the periportal zone in NASH livers. AAV8-mediated RSPO3 overexpression in controls resulted in a zonation change, and further amplified the disturbed zonation of Wnt target genes in NASH, but had no impacts on steatosis, inflammation and fibrosis. In summary, our study demonstrated the alteration of Wnt signaling in a mouse NASH model, leading to perturbed liver zonation.

Tertiary lymphoid structures (TLS) are commonly observed in human idiopathic pulmonary fibrosis (IPF) lungs. The specific immune and non-immune cells in the TLS of IPF patients, and the factors that drive TLS formation, remain largely unknown. Here we spatially deconvoluted immune and non-immune cells in the TLS of human IPF lungs, and examined the signals underlying TSL development in IPF patients. We identified a novel subset of CCL19hi-IPF-associated-mural cells (CCL19hiIAMC) that enveloped the vessels inside the TLS. CCL19hiIAMCs were the major source of CCL19 inside the TLS of IPF lungs, attracting T/B lymphocytes and unique CCR7+DCs to drive TLS formation. CCL19hiIAMCs also provided other pro-TLS and proinflammatory molecules to promote lymphocyte maturation and tissue inflammation. Our data also reveal that various IPF-associated fibroblasts surrounded the TLS, promoting TLS development and plasma cells dissemination via CXCL12/CXCR4 signaling. CCR7 and CXCR4 signaling attracted lymphocytes and DCs that upregulated pro-TLS genes in the IPF microenvironment to enhance TLS formation. Together, these findings have deconvoluted the cell subsets and their transcriptomes in the TLS of IPF lungs and suggest that novel CCL19hiIAMCs may drive TLS formation in collaboration with various immune cells and fibroblasts.

Myocarditis is a severe inflammatory cardiac disease that can progress to dilated cardiomyopathy and heart failure. Experimental autoimmune myocarditis (EAM) represents an animal model of acute myocarditis, which is followed by the development of post-inflammatory cardiac fibrosis and systolic dysfunction. In this model, cardiac inflammation is characterized by the massive influx of myeloid infiltrates and is paralleled by the activation of extracellular matrix-producing cardiac fibroblasts. 6–8-week-old BALB/c mice were immunized with αMyHC peptide together with Complete Freunds’ Adjuvant to induce EAM. Heart tissues were isolated, embedded in OTC, sectioned into 10 µm-thick fragments, and placed on a 10x Genomics Visium Gene Expression Slide. Single-cell spatial libraries were prepared using 10x Genomics Visium protocols, and the sequencing was performed using Illumina Chemistry. Single-cell RNA sequencing data was analyzed using RStudio software. In our analysis, we included three biological time points: a healthy heart (d0), acute myocarditis (d19). Following sequencing, we analyzed 3789 spots under the tissue. We identified the main cell populations present in the mouse heart, including fibroblasts, immune cells, endothelial cells, smooth muscle cells, and cardiomyocytes. Subset analysis on cardiac fibroblasts resulted in the presence of four different subsets (FB1–FB6). Subset FB3 has a myofibroblastic signature defined by the expression of, among others, Acta2, Postn, Vim, Col1a1 and Col3a1. This subset is transiently present at d19 of EAM. Spatial analysis of infiltrating immune cells characterized by the expression of, e.g., Ly6c1 and Lyz2 resulted in the presence of five subsets (INF1–INF5). The INF4 subset is present only at acute myocarditis phase (d19) and is spatiotemporally colocalized with the myofibroblastic subset(FB3). Our data indicate that myofibroblasts and infiltrating immune cells colocalize within the tissue during acute phase of myocarditis. This may indicate active molecular interplay between inflammatory cells and cardiac fibroblasts.

The activity of the cardiac vagal innervation is well known to be crucial to the maintenance of cardiac health, and to protect and recover the heart from injury. Only recently has this role been shown to depend on the activity of the underappreciated Dorsal Motor Nucleus of the Vagus (DMV). By combining neural tracing, transcriptomics, and 3D mapping in male and female Sprague Dawley rats we characterize cardiac-specific neuronal phenotypes in DMV. We find that the DMV cardiac-projecting neurons differentially express PACAP, CART, and synucleins, as well as evidence that they participate in neuromodulatory co-expression involving catecholamines. The significance of these findings is enhanced by previous knowledge of the role of PACAP at the heart and of the other neuromodulators in peripheral vagal targets.

Photoreceptor cell death is a hallmark feature of many retinal degenerative diseases including age-related macular degeneration. At the molecular level, oxidative stress and inflammation are known central pathogenetic drivers, but the spatial and cellular origins of the underlying molecular mechanisms remain unclear. We used spatial transcriptomics to investigate the spatio-temporal gene expression changes in the mouse retina in response to photo-oxidative damage. In both the healthy and degenerating retina, we uncover regionally distinct transcriptomes, with higher expression of immunity related genes in the superior retina. Exposure to photo-oxidative damage increased the expression of genes involved in inflammatory processes, innate immune responses, and cytokine production in a highly localised manner. This focal region seems a key driver of molecular changes, including upregulation of angiogenic pathways. Consequently, we show substantial alterations in vacular endothelial growth factor, pleiotrophin and midkine signalling between retinal layers, some of which are novel angiogenic signalling pathways within the retina.

A critical area of recent cancer research is the emergence of transition states between normal and cancer that exhibit increased cell plasticity which underlies tumor cell heterogeneity. Pancreatic ductal adenocarcinoma (PDAC) arises from a transition state termed acinar-to-ductal metaplasia (ADM), in which digestive enzyme-producing acinar cells acquire a transient ductal epithelium-like phenotype while maintaining their geographical acinar organization. ADM is created by overexpression of the Kruppel-like factor 4 gene (KLF4) in the absence of oncogenic driver mutations. Here, we investigate the DNA methylation landscape and corresponding transcriptional landscape of the mutation-free ADM transition state and the subsequent reversion to a normal acinar phenotype. We ask to what extent cells retain a memory of the ADM transition state via DNA methylation, examine potential regulators of altered DNA methylation during ADM, and investigate the relationship of the ADM transition state to human pancreatic cancer precursor lesions. These findings may inform the mechanisms not only of heritable epigenetic memory of transition states and inflammation, but also of how epigenetic alterations presage or even elicit genetic mutations in cancer.

Systemic sclerosis (SSc) is a devastating autoimmune disease characterized by excessive production and accumulation of extracellular matrix, leading to fibrosis of skin and other internal organs. However, the main cellular participants in SSc skin fibrosis remain incompletely understood. Here using differentiation trajectories at a single cell level, we demonstrate a dual source of extracellular matrix deposition in SSc skin from both myofibroblasts and endothelial-to-mesenchymal-transitioning cells (EndoMT). We further define a central role of Hippo pathway effectors in differentiation and homeostasis of myofibroblast and EndoMT, respectively, and show that myofibroblasts and EndoMTs act as central communication hubs that drive key pro-fibrotic signaling pathways in SSc. Together, our data help characterize myofibroblast differentiation and EndoMT phenotypes in SSc skin, and hint that modulation of the Hippo pathway may contribute in reversing the pro-fibrotic phenotypes in myofibroblasts and EndoMTs.

Gene regulation requires coordinated control of RNA synthesis and degradation, yet measuring RNA turnover across intact tissues remains challenging. Here we present spatial NT-seq, a method that combines transgenesis-free metabolic RNA labeling with in situ chemical recoding on spatial transcriptomics platforms to co-map newly synthesized and pre-existing RNAs. Applying spatial NT-seq to the mouse brain reveals pronounced regional heterogeneity in RNA turnover and identifies the dentate gyrus as a spatial hotspot marked by coordinated up-regulation of basal RNA synthesis and decay. Moreover, spatial NT-seq uncovers rapid, brain region-specific transcriptional and post-transcriptional responses to electroconvulsive stimulation, a clinically relevant treatment for refractory depression. Finally, we leverage computational modeling to identify sequence features and post-transcriptional regulators that shape transcriptome-wide mRNA stability across spatial and cellular contexts in the mouse brain. Together, this integrated “in vivo Timescope” framework provides a spatially resolved view of RNA turnover kinetics and reveals the regulatory architecture of RNA stability in vivo.

Spatial transcriptomics was performed on human hepatoblastomas to determine features associated with histologic heterogeneity.

Antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis is a life-threatening autoimmune disease that often results in kidney failure caused by crescentic glomerulonephritis (ANCA-GN). To date, treatment of most patients with ANCA-GN relies on unspecific immunosuppressive agents that harbor serious adverse effects and limited efficiency. Using spatial and single-cell transcriptome analysis we characterized inflammatory niches in the kidneys of 34 patients with ANCA-GN and idenjpgied proinflammatory cytokine producing CD4+ and CD8+ T cells as a key pathogenic tissue signature. By employing digital pharmacology we then idenjpgied ustekinumab, a monoclonal antibody targeting IL-12 and IL-23 in these T cells, as promising therapeutic avenue. Based on these findings, four patients with relapsing ANCA-GN were treated with ustekinumab in combination with low-dose cyclophosphamide. Ustekinumab was given subcutaneously (90 mg) at weeks 0, 4, 12, and 24 and clinical and renal response were evaluated at week 26. Treatment induced substantial clinical response in all ANCA-GN patients, with improvements in kidney function, and Birmingham Vasculitis Activity Score, and was well tolerated. Our findings suggest that the pathogenesis-based treatment of ANCA-GN patients with ustekinumab is efficacious and warrants further investigation in clinical trials.

Desmoplastic Small Round Cell Tumor (DSRCT) is a rare, aggressive sarcoma driven by the EWSR1-WT1 chimeric transcription factor. Despite this unique oncogenic driver, DSRCT displays a polyphenotypic differentiation of unknown causality. Using single-cell multi-omics on samples from patients, we find that DSRCT tumor cells cluster into consistant subpopulations with partially overlapping lineage- and metabolism-related transcriptional programs.

Head and neck squamous cell carcinoma is the 6th most common malignancy worldwide. We performed spatial transcriptomics to profile intra- and inter-tumor heterogeneity. We identified recurring patterns of spatial gene expression that co-localize in subsets of tumors.

Copper (Cu) is an essential trace element required for mitochondrial respiration. We show that Cu drives coordinated metabolic remodeling of bioenergy, biosynthesis and redox homeostasis and promotes tumor growth and progression of clear cell renal cell carcinoma (ccRCC). Late-stage ccRCCs accumulate Cu and allocate it to cytochrome c oxidase stimulating bioenergy production. Cu induces TCA cycle-dependent oxidation of glucose and its utilization for biosynthesis of a glutathione pool that protects against H2O2 generated during mitochondrial respiration, therefore coordinating bioenergy production with redox protection. Single cell transcriptomics determined induction of mitochondrial electron transport chain, expression of NRF2 targets and glutathione biosynthesis, and decrease in HIF activity, the hallmark of ccRCC, during disease progression. Spatial transcriptomics identified that cancer cells with proliferative phenotype are embedded in clusters of cells with oxidative metabolism supporting effects of metabolic states on ccRCC progression. Our work establishes novel vulnerabilities with potential for therapeutic interventions in ccRCC.

Fibrosis, the replacement of healthy tissue with collagen-rich matrix, can occur following injury in almost every organ. Mouse lungs follow stereotyped sequences of fibrogenesis-to-resolution after bleomycin injury, and we reasoned that profiling post-injury histological progression could uncover pro- vs. anti-fibrotic features with functional value for human fibrosis. We mapped spatiotemporally-resolved transformations in lung extracellular matrix (ECM) architecture to spatially-resolved, multi-omic data. First, we charted stepwise trajectories of matrix aberration vs. resolution using unsupervised machine learning, denoting a reversible transition in uniform-to-disordered histological architecture. Single-cell sequencing along these trajectories identified temporally-enriched “ECM-secreting” (Csmd1+) and “pro-resolving” (Cd248+) fibroblasts, for which Visium inferred divergent histological signatures and spatial-transcriptional “neighborhoods”. Critically, pro-resolving fibroblast instillation helped ameliorate fibrosis in vivo. Further, fibroblast neighborhood-associated moieties, Serpine2 and Pi16, functionally modulated human lung fibrosis ex vivo. Spatial phenotyping of idiopathic pulmonary fibrosis further uncovered analogous fibroblast subtypes and neighborhoods in human disease. Collectively, these findings establish an atlas of pro-/anti-fibrotic factors underlying lung matrix architecture and implicate fibroblast-centered moieties in modulating fibrotic progression vs. resolution.

Thyroid cancer ranks as the ninth most common cancer type in terms of incidence worldwide. Furthermore, the global incidence of thyroid cancer has been on the rise over the past decades.Spatial transcriptomics technology systematically profiles gene expression across tissue space by combing high-throughput RNA sequencing and imaging techniques. The applications of ST have revealed high-resolution spatial architecture and cellular crosstalk in many tumor types, advancing the discovery of new targets for diagnosis and therapy. However, the spatial architecture in thyroid cancer and the structural differences in the TME among papillary thyroid cancer (PTC), locally advanced thyroid cancer (LPTC), and Anaplastic thyroid carcinoma (ATC) have been little investigated. Herein , we applied ST and scRNA-seq data to reveal the spatial difference of TME in PTC, LPTC, and ATC samples.

Leptomeningeal disease (LMD) remains a rapidly lethal complication for late-stage melanoma patients. The inaccessible nature of the disease site and lack of understanding of the biology of this unique metastatic site are major barriers to developing efficacious therapies for patients with melanoma LMD. This study aims to characterize the tumor microenvironment of the leptomeningeal tissues and patient-matched extra-cranial metastatic sites using spatial transcriptomic analyses.

Intestinal homeostasis is maintained by the response of gut-associated lymphoid tissue to bacteria transported across the follicle associated epithelium into the subepithelial dome. The initial response to antigens and how bacteria are handled is incompletely understood. By iterative application of spatial transcriptomics and multiplexed single-cell technologies, we identify that the double negative 2 subset of B cells, previously associated with autoimmune diseases, is present in the subepithelial dome in health. We show that in this location double negative 2 B cells interact with dendritic cells co-expressing the lupus autoantigens DNASE1L3 and C1q and microbicides. We observe that in humans, but not in mice, dendritic cells expressing DNASE1L3 are associated with sampled bacteria but not DNA derived from apoptotic cells. We propose that fundamental features of autoimmune diseases are microbiota-associated, interacting components of normal intestinal immunity.

Objective: To spatially resolve the identified celltypes, subtypes and transcriptomic profiles from single-nuclei RNA-seq with matched 12 infrapatellar fat pad of knee OA patients using spatial transcriptomics sequencing.

The mouse uterine gene expressions during peri-implantation period at pregnancy day 4 and 6 was investigated by Visium spatial transcriptome.

Tumor-immune microenvironment is instrumental in shaping breast cancer tumor evolution. We previously identified an evolutionary bottleneck demarcating ductal carcinoma in situ (DCIS) from invasive ductal carcinoma (IDC). How the microenvironment evolves during such transition remains elusive. We dissected, in parallel, single-cell composition of DCIS and IDC patients and rat tumors that faithfully recapitulate human breast cancer. We discovered T cell diversity distinguishing DCIS and IDC and a novel cycling Treg state occupying the pseudotime bifurcation between DCIS and IDC, preceding more activated Treg subtypes. Multiscale analysis of patient cohorts as part of HTAN Consortium established that cycling Treg predicts recurrence in low-grade DCIS. We proved cycling Treg as Treg progenitors critical for immune escape and demonstrated that OX40 agonism restored immunotherapeutic sensitivity, where responders displayed increased inflammatory CAF subtype heterogeneity. Our study thus established cycling Treg’s importance in preserving immune escape and underscored its prognostic value to stratify future recurrence.

The adrenal gland is a fundamental endocrine organ exhibiting constant renewal. Despite extensive work in rodents, human-specific aspects of hormone-producing cell populations, stem cells, and self-renewal mechanisms are not fully understood. To fill this knowledge gap and address species-specific features, we generated high density single-cell and spatial transcriptomics atlases of adult human and mouse adrenal glands using Visium, VisiumHD and Stereo-seq, covering a spectrum of sexes and ages. Our comparisons between human and murine adrenal gland revealed significant evolutionary divergence despite homology in function of specific regions, which questiones the applicability of mouse models in studies of human adrenal disorders. Self-renewal mechanisms in adrenocortical populations that were previously discovered in mice also revealed human-specific features or were confronted by human-specific transitions not evident in rodents. The latter included specific perivascular mesenchymal progenitors, and dispersed SF1+/EZH2+ progenitor cells, which implies that human adrenocortical cells may be renewed in a localized manner in addition to the centripetal model. We also engaged in cross-comparison of our adult human adrenals with fetal stages to reveal developmental strategies still operating as a part of self-renewal in adults. Unexpectedly, human SF1+/EZH2+ progenitors turned out to be operating during adrenocortical development and later during adult stages, albeit in different degrees. At last, we revealed sex-specific differences in human cholesterol metabolism and other features reflecting human and mouse sexual dimorphism in adrenal glands. Overall, our new comparative mouse-human atlases shall provide an additional resource for further molecular interrogations of adrenal gland biology and pathology.

Fibroblasts and immune cells coordinate tissue regeneration and necessary scarring after injury. In the brain, fibroblasts are border-enriched cells whose dynamic molecular states and immune interactions after injury remain unclear. We used spatial transcriptomics (10X Visium) to spatiotemporally profile CNS wound healing responses, including stromal and immune responses, after photothrombotic (PT) injury.

Macrophages (Mf) are the most abundant mononuclear phagocytes in tumor tissues and hold promise as therapeutic targets and indicators of disease progression. In this work, we mapped by single-cell analysis the distinct Mf populations infiltrating the invasive margin and normal adjacent regions of human colo-rectal liver metastasis (CLM), and we exploited this information to identify non redundant markers with clinical relevance. Different populations were enriched in the invasive margin, including early-mature, inflammatory Mf (MoMf) expressing the monocytic markers S100A12 and SERPINB2, and a more mature population (TAMs) expressing CD68, GPNMB and TREM2. TAMs were enriched in pathways of matrix degradation, angiogenesis and lipid metabolism, similarly to dysfunctional macrophages described in other tumors. Cell-cell interaction analysis with CD8+ T cells defined opposing roles of MoMf, predicted to interact via IL-15, and TAMs, engaging T cells via IL-20 and IL-10. By multiplex immunofluorescence in CLM sections, we confirmed that SERPINB2 and GPNMB are expressed by different Mf subsets, with distinct topographical distribution and opposite association with patient clinical outcome.

Spatial transcriptomics facilitates the understanding of gene expression within complex tissue contexts. Among the array of spatial capture technologies available is 10x Genomics’ Visium which provides whole tissue section profiling, enabling whole transcriptome spatial analysis. Our dataset comprises spleen tissue from mice infected with malaria, spanning multiple experiments and sample preparation protocols for tissue preservation, either as fresh frozen at optimal cutting temperature (OCT) or formalin-fixed paraffin-embedded (FFPE). Tissue placement was also considered, comparing direct tissue placement on the slide with the use of CytAssist (CA), which expands the Visium platform’s capabilities by allowing for the pre-selection of tissue sections and genes through a set of probes. We also include a matching scRNA-seq dataset that can be integrated with the spatial data.

To elucidate how antigen-specific CD4 T cells indirectly repress tumor growth independently of other lymphocytes, we first sought to gain insight into the changes they induced in the tumor micro-environment (TME) using the 10x Genomics Visium technology

Spinal cord injury (SCI) triggers a cascade of intricate molecular and cellular changes that determine the outcome. In this study, we resolve the spatiotemporal organization of the injured mouse spinal cord and quantitatively assess in situ cell-cell communication following SCI. By analyzing existing single-cell RNA-sequencing datasets alongside our spatial data, we delineate a subpopulation of Igfbp2-expressing astrocytes that migrate from the white matter (WM) to grey matter (GM) and become reactive upon SCI, termed as Astro-GMii. Further, Igfbp2 upregulation promotes astrocyte migration, proliferation and reactivity, and the secreted IGFBP2 protein fosters neurite outgrowth. Finally, we show that IGFBP2 significantly reduces neuronal loss and remarkably improves the functional recovery in a mouse model of SCI in vivo. Together, this study not only provides a comprehensive molecular atlas of SCI but also exemplifies how the rich resource can be applied to endow cells and genes with functional insight and therapeutic potential.

Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs) and the release of fibrogenic nano-sized extracellular vesicles (EVs). Activated HSCs increase their glucose metabolism via glycolysis to satisfy high energy demands. Nevertheless, the mechanism of how glycolysis in HSCs coordinates fibrosis amplification in the fibrogenic zones in the liver is elusive and is the scope of this study. Single cell RNA sequencing (scRNAseq) and bulk RNAseq demonstrated that several glycolysis enzymes, including hexokinase 2 (HK2), were upregulated in activated HSCs. HSC-selective glycolysis-deficient mice (HK2ΔHSC) showed abrogated CCl4-mediated fibrosis as compared to littermate controls (HK2fl/fl). Spatial transcriptomics revealed an upregulation of several EV-related pathways in the fibrotic pericentral zone during liver fibrosis in control HK2fl/fl mice. However, glycolysis-deficient HK2ΔHSC mice showed downregulation of these EV-related pathways in the pericentral zone. Consistently, induction of glycolysis in HSCs in vitro, either by glucose or platelet-derived growth factor B (PDGF), upregulated the expression of several extracellular vesicle (EV)-related genes, including RAB31. Glycolysis in HSCs epigenetically enhanced RAB31 expression through histone-3 lysine-9 acetylation (H3K9ac) on the promoter region, leading to increased EV release. Functionally, glycolysis-dependent EVs were enriched with fibrogenic molecules and increased the expression of fibrotic markers in recipient HSCs. Finally, EVs derived from glycolysis-deficient HK2ΔHSC mice abrogated liver fibrosis amplification as compared to EVs derived from littermate control HK2fl/fl mice. In summary, glycolysis in HSCs amplifies liver fibrosis by promoting fibrogenic EV release in the pericentral fibrotic regions in the liver.

The germinal center (GC) dark zone (DZ) and light zone (LZ) regions spatially separate expansion and diversification from selection of antigen-specific B-cells to ensure antibody affinity maturation and B cell memory. How GC polarity is established is poorly understood. This study provides novel insights into signals controlling asymmetric T-cell distribution between DZ and LZ regions. We identify spatially-resolved DNA damage response and chromatin compaction molecular features precluding DZ T-cell infiltration. The DZ spatial transcriptional signature linked to T-cell immune evasion clustered aggressive Diffuse Large B-cell Lymphomas (DLBCL) for differential T cell infiltration. We reveal the dependence of the DZ transcriptional core signature on the ATR kinase and dissect its role in restraining inflammatory responses contributing to estabslish an immune-repulsive imprint in DLBCL. These insights may guide ATR-focused treatment strategies bolstering immunotherapy in tumors marked by DZ transcriptional and chromatin-associated features.

Background & Aims: Hepatoblastoma is the most common pediatric cancer of the liver and the majority of cases display activating mutations in the Wnt/β-catenin pathway. Understanding the complex milieu of the tumor microenvironment has resulted in promising new therapies for adult cancers, but similar approaches in pediatric cancers are still lacking. We aimed to provide a comprehensive analysis of the tumor microenvironment of hepatoblastoma unveiling its spatial architecture and key signaling mechanisms. Methods: Single-cell/-nucleus RNA-seq (n=15), spatial transcriptomics (n=22), and multiplex immunofluorescence stainings (n=7) of treated, untreated, and metastasized pediatric hepatoblastomas were performed. An RNA-seq validation cohort (n=110) including hepatoblastoma, non-tumor and fetal liver samples and single-cell RNA-seq data of healthy immune cells were used for further analysis. Western blotting and RNA-seq of hepatoblastoma and macrophage cell lines were conducted for experimental validation. Results: Of four identified transcriptional tumor programs, “Developmental” and “Metabolic” reflected different hepatic differentiation stages, while “Cycling” was enriched in undifferentiated cells and relapsed samples, and “Intermediate” displayed high activity in samples from patients with poor outcomes. We discovered an increased ratio of anti- to pro-inflammatory immune cells and evidence of immune exclusion from tumor areas. Wnt-responsive upregulation of the immunomodulator midkine in hepatoblastoma cells was associated with a change in macrophage phenotype, which could be partially reversed through midkine inhibition. Conclusions: Hepatoblastoma cells exist along a continuous spectrum of hepatic differentiation and inhabit an altered immune environment. Wnt signaling augments midkine expression, which appears to be involved in shaping the immune environment by modifying macrophages to enable immune evasion, thereby providing a potential therapeutic target.

Myocardial infarctions (MI) affect 805,000 people per year in the United States. To mitigate the pathological effects of MI, we have developed and investigated pro-reparative decellularized extracellular matrix (ECM) hydrogels. However, no one has ever utilized single cell and spatially resolved transcriptomics to further probe how ECM can elicit pro-repair in an MI model. Thus, we utilize spatial transcriptomics and single nucleus RNA sequencing (snRNAseq) to further delineate the regional and cell-specific bioactivity of decellularized ECM hydrogels. ECM hydrogel subacute treatment induced cardiac resident macrophage preservation, fibroblast activation, increased vasculature development, and a cardiomyocyte development program. Similar findings of cardiomyocyte and vasculature development, alongside fibroblast development was found for chronic treatment. Thus, we depict the pro-reparative nature of decellularized ECM hydrogels on cardiac cell types and elucidate previously undiscovered therapeutic pathways, further demonstrating ECM’s potential as an MI therapy.

Sarcoidosis is a chronic inflammatory disorder characterized by the presence of tiny collections of immune cells known as granulomas. An incomplete understanding of etiology and immune-pathologic pathways have limited the development of quality biomarkers and novel targeted therapies. We found a Fsp1-Cre mediated TSC1/2 deletion mice unexpectedly led to development of a disease state, which was identified and characterized by spatial transcriptomics and single-cell RNA sequencing, similar to sarcoidosis. Notably, we identified CCL24 as a novel key chemotactic regulator in this model of sarcoidosis and found decreased CCL24 in the sarcoid group, thus translating our model and hypothesis to the human form of the disease. Intriguingly, we found that CCL24 and azithromycin significantly blocked the progression of granuloma formation in this model. Our findings not only improve an integrated understanding of the progression of sarcoidosis but also provide the basis for developing novel potential clinical interventions in sarcoidosis therapeutics.

Alzheimer’s disease (AD) therapies utilizing amyloid-β (Aβ) immunization have shown potential in clinical trials. Yet, the mechanisms driving Aβ clearance in the immunized AD brain remain unclear. Here, we use spatial transcriptomics to explore the effects of both active and passive Aβ immunization in the AD brain. We compare actively immunized AD patients with nonimmunized AD patients and neurologically healthy controls, identifying distinct microglial states associated with Aβ clearance. Using high-resolution spatial transcriptomics alongside single-cell RNA sequencing, we delve deeper into the transcriptional pathways involved in Aβ removal after lecanemab treatment. We uncover spatially distinct microglial responses that vary by brain region. Our analysis reveals upregulation of the triggering receptor expressed on myeloid cells 2 (TREM2) and apolipoprotein E (APOE) in microglia across immunization approaches, which correlate positively with antibody responses and Aβ removal. Furthermore, we show that complement signaling in brain myeloid cells contributes to Aβ clearance after immunization. These findings provide new insights into the transcriptional mechanisms orchestrating Aβ removal and shed light on the role of microglia in immune-mediated Aβ clearance. Importantly, our work uncovers potential molecular targets that could enhance Aβ-targeted immunotherapies, offering new avenues for developing more effective therapeutic strategies to combat AD.

Small cell lung cancer is a lung tumor with extremely poor prognosis, and its tumor heterogeneity and unique microenvironment remain unclear. This study aimed to reveal the early tumorigenesis and microenvironment of small cell lung cancer by performing idle transcriptomic sequencing of patients' small cell lung cancer tissues.

We investigated the mechanisms by which inflammatory responses generated by tumor-specific T cells delivered to ovarian tumor-bearing mice alone or after oncolytic vaccinia virus-driven immunogenic cancer cell death affect antitumor efficacy using spatial transcriptomics.