Hair growth is induced by blockade of macrophage-derived oncostatin M and JAK-STAT5 signaling in hair follicle stem cells.

We also show that OSM is sufficient for maintaining quiescence of hair follicle stem cells (HFSCs), and OSMRβ-JAK-STAT5 signaling is necessary for maintaining the resting phase of the hair cycle (telogen). Using single-cell RNA sequencing, we identify the source of OSM to be a distinct subset of TREM2+ macrophages that predominate during early telogen. Moreover, inhibition of macrophages during telogen by genetic ablation, neutralizing antibodies and small-molecule inhibitors was sufficient to induce anagen. Single-cell RNA sequencing of CD45+ immune cells at 4 timepoints during murine telogen.

我们还证实，抑瘤素M（Oncostatin M, OSM）足以维持毛囊干细胞（hair follicle stem cells, HFSCs）的静息状态，且OSMRβ-JAK-STAT5信号通路对于维持毛发周期的休止期（telogen）是必需的。本研究通过单细胞RNA测序，确定OSM的来源为一类独特的TREM2阳性巨噬细胞亚群，该亚群在休止早期占据主导地位。此外，在休止期通过基因敲除、中和抗体以及小分子抑制剂对巨噬细胞进行抑制，足以诱导毛发周期进入生长期（anagen）。本研究对小鼠休止期四个时间点的CD45阳性免疫细胞开展了单细胞RNA测序。