RESUMO
Optimal tissue recovery and organismal survival are achieved by spatiotemporal tuning of tissue inflammation, contraction and scar formation1. Here we identify a multipotent fibroblast progenitor marked by CD201 expression in the fascia, the deepest connective tissue layer of the skin. Using skin injury models in mice, single-cell transcriptomics and genetic lineage tracing, ablation and gene deletion models, we demonstrate that CD201+ progenitors control the pace of wound healing by generating multiple specialized cell types, from proinflammatory fibroblasts to myofibroblasts, in a spatiotemporally tuned sequence. We identified retinoic acid and hypoxia signalling as the entry checkpoints into proinflammatory and myofibroblast states. Modulating CD201+ progenitor differentiation impaired the spatiotemporal appearances of fibroblasts and chronically delayed wound healing. The discovery of proinflammatory and myofibroblast progenitors and their differentiation pathways provide a new roadmap to understand and clinically treat impaired wound healing.
Assuntos
Receptor de Proteína C Endotelial , Fáscia , Cicatrização , Animais , Camundongos , Diferenciação Celular , Hipóxia Celular , Linhagem da Célula , Modelos Animais de Doenças , Receptor de Proteína C Endotelial/metabolismo , Fáscia/citologia , Fáscia/lesões , Fáscia/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Inflamação/metabolismo , Inflamação/patologia , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Transdução de Sinais , Análise da Expressão Gênica de Célula Única , Pele/citologia , Pele/lesões , Pele/metabolismo , Tretinoína/metabolismoRESUMO
The mammalian global response to sealing deep tissue wounds is through scar formation and tissue contraction, mediated by specialized fascia fibroblasts. Despite the clinical significance of scar formation and impaired wound healing, our understanding of fascia fibroblast dynamics in wound healing is cursory due to the lack of relevant assays that enable direct visualization of fibroblast choreography and dynamics in complex environments such as in skin wounds. This paper presents a protocol to generate ex- situ skin scars using SCAD or "SCar-like tissue in A Dish" that emulate the complex environment of skin wounds. In this assay, 2 mm full-thickness skin is excised and cultured upside down in media for 5 days, during which scars and skin contractures develop uniformly. This methodology, coupled with fibroblast-lineage specific transgenic mouse models, enables visualization of individual fibroblast lineages across the entire wound repair process. Overall, this protocol aids researchers in understanding fundamental processes and mechanisms of wound repair, directly exploring the effects of modulators on wound healing outcomes.
