CD80 on skin stem cells promotes local expansion of regulatory T cells upon injury to orchestrate repair within an inflammatory environment

• DOI: 10.1016/j.immuni.2024.04.003
• Publication Date: 2024-04-26T14:31:55Z
• Authors: Jingyun Luan; Cynthia Truong; Aleksandra Vuchko...; Weijie Guo; Jennifer Good; Bijun Liu; Audrey Gang; Nicole Infarinato; Katherine Stewart; Lisa Polak; Hilda Amalia Pasolli; Emma Andretta; Alexander Y. Rude...; Elaine Fuchs; Yuxuan Miao
• Keywords: CD80; Inflammatory response

Following tissue damage, epithelial stem cells (SCs) are mobilized to enter the wound, where they confront harsh inflammatory environments that can impede their ability repair injury. Here, we investigated mechanisms protect skin SCs within this environment. Characterization of gene expression profiles hair follicle (HFSCs) migrated into wound site revealed activation an immune-modulatory program, including CD80, major histocompatibility complex class II (MHCII), and CXC motif chemokine ligand 5 (CXCL5). Deletion CD80 in HFSCs impaired re-epithelialization, reduced accumulation peripherally generated Treg (pTreg) cells, increased infiltration neutrophils wounded skin. Importantly, similar healing defects were also observed mice lacking pTreg cells. Our findings suggest upon injury, establish a temporary protective network by promoting local expansion thereby enabling re-epithelialization while still kindling inflammation outside niche until barrier is restored.