Single-cell analysis reveals fibroblast heterogeneity and myeloid-derived adipocyte progenitors in murine skin wounds

Nat Commun. 2019 Feb 8;10(1):650. doi: 10.1038/s41467-018-08247-x.

Abstract

During wound healing in adult mouse skin, hair follicles and then adipocytes regenerate. Adipocytes regenerate from myofibroblasts, a specialized contractile wound fibroblast. Here we study wound fibroblast diversity using single-cell RNA-sequencing. On analysis, wound fibroblasts group into twelve clusters. Pseudotime and RNA velocity analyses reveal that some clusters likely represent consecutive differentiation states toward a contractile phenotype, while others appear to represent distinct fibroblast lineages. One subset of fibroblasts expresses hematopoietic markers, suggesting their myeloid origin. We validate this finding using single-cell western blot and single-cell RNA-sequencing on genetically labeled myofibroblasts. Using bone marrow transplantation and Cre recombinase-based lineage tracing experiments, we rule out cell fusion events and confirm that hematopoietic lineage cells give rise to a subset of myofibroblasts and rare regenerated adipocytes. In conclusion, our study reveals that wounding induces a high degree of heterogeneity among fibroblasts and recruits highly plastic myeloid cells that contribute to adipocyte regeneration.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / cytology*
  • Adipocytes / metabolism*
  • Animals
  • Blotting, Western
  • Cells, Cultured
  • Female
  • Fibroblasts / cytology*
  • Fibroblasts / metabolism*
  • Male
  • Mice
  • Sequence Analysis, RNA
  • Single-Cell Analysis / methods*
  • Skin / cytology*
  • Stem Cells / cytology*
  • Stem Cells / metabolism
  • Wound Healing / physiology