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Biology subjects

Penland, L.

Publications and source records attributed to Penland, L..

5 recordsLinked to original sources

PTPN1/2 inhibits alveolar macrophage-mediated control of lung metastasis

Metastasis remains the leading cause of cancer mortality, yet effective therapies are limited. While therapeutic responses are influenced by organ-specific immune microenvironments, strategies to pharmacologically modulate these niches remain poorly defined. Here, using the clinical-stage inhibitor ABBV-CLS-484 (AC484) as a chemical probe, we demonstrate that systemic PTPN1/2 inhibition remodels the pulmonary myeloid landscape, specifically activating alveolar macrophages (AMs) toward a tumoricidal state. Integrated single-cell/spatial transcriptomics and functional assays reveal that AC484 promotes AM accumulation within metastatic lesions, elevates their IFN{gamma} production and responsiveness, and enhances their tumor-killing activity. Depletion of AMs diminishes the anti-metastatic efficacy of AC484. Mechanistically, inhibiting PTPN1/2 by AC484 amplifies IFN{gamma}-STAT1 signaling in AMs, while disrupting this pathway impairs their tumor control capability. These findings delineate a distinct innate immune axis where PTPN1/2 acts as a molecular "brake" on AM activation, suggesting that pharmacologically unleashing tissue-resident macrophages offers a therapeutic strategy to overcome metastatic progression, particularly in microenvironments where adaptive immunity is insufficient. SignificanceAMs are potent anti-metastatic immune effectors functionally constrained by PTPN1/2. Pharmacologically inhibiting PTPN1/2 amplifies their IFN{gamma}-STAT1 signaling and tumoricidal activity, establishing a strategy to reactivate tissue-resident immunity against metastasis.

immunology↗

Tabula Microcebus: A transcriptomic cell atlas of mouse lemur, an emerging primate model organism

Mouse lemurs are the smallest, fastest reproducing, and among the most abundant primates, and an emerging model organism for primate biology, behavior, health and conservation. Although much has been learned about their physiology and their Madagascar ecology and phylogeny, little is known about their cellular and molecular biology. Here we used droplet- and plate-based single cell RNA-sequencing to profile 226,000 cells from 27 mouse lemur organs and tissues opportunistically procured from four donors clinically and histologically characterized. Using computational cell clustering, integration, and expert cell annotation, we defined and biologically organized over 750 mouse lemur molecular cell types and their full gene expression profiles. These include cognates of most classical human cell types, including stem and progenitor cells, and the developmental programs for spermatogenesis, hematopoiesis, and other adult tissues. We also described dozens of previously unidentified or sparsely characterized cell types and subtypes. We globally compared cell type expression profiles to define the molecular relationships of cell types across the body, and explored primate cell and gene expression evolution by comparing mouse lemur cell transcriptomes to those of human, mouse, and macaque. This revealed cell type specific patterns of primate specialization, as well as many cell types and genes for which lemur provides a better human model than mouse. The atlas provides a cellular and molecular foundation for studying this primate model organism, and establishes a general approach for other emerging model organisms.

genetics↗

A molecular cell atlas of the human lung from single cell RNA sequencing

Although single cell RNA sequencing studies have begun providing compendia of cell expression profiles, it has proven more difficult to systematically identify and localize all molecular cell types in individual organs to create a full molecular cell atlas. Here we describe droplet- and plate-based single cell RNA sequencing applied to [~]75,000 human lung and blood cells, combined with a multi-pronged cell annotation approach, which have allowed us to define the gene expression profiles and anatomical locations of 58 cell populations in the human lung, including 41 of 45 previously known cell types or subtypes and 14 new ones. This comprehensive molecular atlas elucidates the biochemical functions of lung cell types and the cell-selective transcription factors and optimal markers for making and monitoring them; defines the cell targets of circulating hormones and predicts local signaling interactions including sources and targets of chemokines in immune cell trafficking and expression changes on lung homing; and identifies the cell types directly affected by lung disease genes and respiratory viruses. Comparison to mouse identified 17 molecular types that appear to have been gained or lost during lung evolution and others whose expression profiles have been substantially altered, revealing extensive plasticity of cell types and cell-type-specific gene expression during organ evolution including expression switches between cell types. This atlas provides the molecular foundation for investigating how lung cell identities, functions, and interactions are achieved in development and tissue engineering and altered in disease and evolution.

genomics↗

A murine aging cell atlas reveals cell identity and tissue-specific trajectories of aging

BackgroundAging is a pleiotropic process affecting many aspects of organismal and cellular physiology. Mammalian organisms are composed of a constellation of distinct cell type and state identities residing within different tissue environments. Due to technological limitations, the study of aging has traditionally focused on changes within individual cell types, or the aggregate changes across cell types within a tissue. The influence of cell identity and tissue environment on the trajectory of aging therefore remains unclear.\n\nResultsHere, we perform single cell RNA-seq on >50,000 individual cells across three tissues in young and aged mice. These molecular profiles allow for comparison of aging phenotypes across cell types and tissue environments. We find transcriptional features of aging common across many cell types, as well as features of aging unique to each type. Leveraging matrix factorization and optimal transport methods, we compute a trajectory and magnitude of aging for each cell type. We find that cell type exerts a larger influence on these measures than tissue environment.\n\nConclusionIn this study, we use single cell RNA-seq to dissect the influence of cell identity and tissue environment on the aging process. Single cell analysis reveals that cell identities age in unique ways, with some common features of aging shared across identities. We find that both cell identities and tissue environments exert influence on the trajectory and magnitude of aging, with cell identity influence predominating. These results suggest that aging manifests with unique directionality and magnitude across the diverse cell identities in mammals.

bioinformatics↗

High fidelity hypothermic preservation of primary tissues in organ transplant preservative for single cell transcriptome analysis

BackgroundHigh-fidelity preservation strategies for primary tissues are in great demand in the single cell RNAseq community. A reliable method will greatly expand the scope of feasible collaborations and maximize the utilization of technical expertise. When choosing a method, standardizability is as important a factor to consider as fidelity due to the susceptibility of single-cell RNAseq analysis to technical noises. Existing approaches such as cryopreservation and chemical fixation are less than ideal for failing to satisfy either or both of these standards.\n\nResultsHere we propose a new strategy that leverages preservation schemes developed for organ transplantation. We evaluated the strategy by storing intact mouse kidneys in organ transplant preservative solution at hypothermic temperature for up to 4 days (6 hrs, 1, 2, 3, and 4 days), and comparing the quality of preserved and fresh samples using FACS and single cell RNAseq. We demonstrate that the strategy effectively maintained cell viability, transcriptome integrity, cell population heterogeneity, and transcriptome landscape stability for samples after up to 3 days of preservation. The strategy also facilitated the definition of the diverse spectrum of kidney resident immune cells, to our knowledge the first time at single cell resolution.\n\nConclusionsHypothermic storage of intact primary tissues in organ transplant preservative maintains the quality and stability of the transcriptome of cells for single cell RNAseq analysis. The strategy is readily generalizable to primary specimens from other tissue types for single cell RNAseq analysis.

genomics↗