Prokaryotic 16S rRNA / Stool microbial communities of wild-type and Retnla-/- mice

Vitamin A deficiency increases susceptibility to skin infection yet how vitamin A regulates skin immunity remains unclear. Here, we show that resistin-like molecule RELM is a skin antimicrobial protein that is required for vitamin A-dependent resistance to skin infection. RELM was induced in mouse skin by bacterial colonization, killed skin bacteria in vitro, and protected against bacterial infection of the skin in vivo.