FPR2 and pulmonary fibrosis: Recent studies have indicated that 17(R)-RvD1 attenuated bleomycin-induced pulmonary fibrosis by promoting the resolution of neutrophilic inflammation in mice.44 Treatment with 17(R)-RvD1 attenuated neutrophil alveolar infiltration, lung collagen content, and type I collagen mRNA expression, which was inhibited by an antagonist of ALX/FPR2 receptor.44 RvD1 can suppress renal fibrosis in the obstructed kidney via inhibiting fibroblast proliferation and production of fibronectin and collagen I.45, 46 We therefore studied the effects of RvD1 upon primary HLF.