RAE1 and Hepatic fibrosis: Activated HSCs usually have high expression of NKG2D (natural killer group 2 member D) ligand Rae1(retinoic acid early inducible 1), IL-30 stimulates the high expression of NKG2D in NKTs, and NKTs eventually kill the active HSCs and improve liver fibrosis by combining nKG2D-RAE1 with highly specific targeted activated HSCs (Mitra et al., 2014).