Fibroblasts of disparate developmental origins harbor anatomically variant scarring potential

Abstract

Progress toward anti-scarring therapies has been hampered by our limited understanding of fibroblast populations underlying fibrotic vs. regenerative healing. The site-dependent fibroblast heterogeneity acquired during development points to cell-intrinsic properties determining fibroblasts' scarring potential. Using a mouse wounding model, we observed that facial wounds heal with less scarring than scalp, ventral, and dorsal wounds. Single-cell RNA sequencing identified increased expression of Robo2 and downstream Eid1 in neural-crest-derived facial fibroblasts compared with fibroblasts from other sites. In fibroblast transplantation experiments, Robo2 and Eid1 promoted facial fibroblasts' reduced fibrotic potential. This is maintained by the inhibition of EP300 histone acetyltransferase, leading to a more transcriptionally silent chromatin landscape. Mimicking EID1's activity, small-molecule and transgenic EP300 repression in dorsal wounds promoted facial-like healing with reduced scarring. These data highlight the importance of ROBO2-EID1-EP300 signaling in facial wound healing and demonstrate our ability to modulate fibroblasts' embryologically determined fibrogenic potential to minimize scarring.

Keywords: fibroblast; fibrosis; healing; neural crest; scar; single-cell RNA sequencing; skin; wound.