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Biology subjects

Hu, M. S.

Publications and source records attributed to Hu, M. S..

2 recordsLinked to original sources

Integrated spatial multi-omics reveals fibroblast fate during tissue repair

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. These findings have broad implications for the study of tissue repair in complex organ systems.

bioinformatics↗

Endothelial CXCL12 regulates neovascularization during tissue repair and tumor progression

CXC chemokine ligand 12 (CXCL12; stromal cell-derived factor 1 [SDF-1]), primarily known for its role in embryogenesis and hematopoiesis, has also been implicated in tumor biology and neovascularization. However, its specific role and mechanism of action remain poorly understood. We previously demonstrated that CXCL12 expression is Hypoxia-Inducible Factor (HIF)-1 responsive. Here we use a conditional CXCL12 knockout mouse to show that endothelial-specific deletion of CXCL12 (eKO) does not affect embryogenesis, but reduces the survival of ischemic tissue, altering tissue repair and tumor progression. Loss of vascular endothelial CXCL12 disrupts endothelial - fibroblast crosstalk necessary for stromal growth and vascularization. Single-cell gene expression analysis in combination with a parabiosis model reveals a specific population of non-inflammatory circulating cells, defined by genes regulating neovascularization, which is recruited by endothelial CXCL12. These findings indicate an essential role for endothelial CXCL12 expression during the adult neovascular response in tissue injury and tumor progression.

molecular biology↗