ACTA1 and renal fibrosis: In addition, knocking down ITL4 significantly reduces the T‐cell inhibitory ability of MDSCs in vitro and significantly reduces MDSC‐induced renal fibrosis in ADR‐induced mice in vivo, manifested by the decreased collagen deposition in Masson staining results and decreased expression of α‐SMA and collagen I proteins in immunohistochemical results.