S100A4 and renal fibrosis: In a transplantation study of autologous AMSCs, Song et al. [23] transplanted AMSCs into UUO model rats by tail vein injection and reported that AMSCs decreased MCP-1, TLR4, TNF-α, IL-1β, IL-6, TGF-β1, Smad2/3, α-SMA, fibroblast-specific protein 1 (FSP-1), and FN and inhibited renal fibrosis.