Regulation of recombinant Trichinella spiralis 53-kDa protein (rTsP53) on alternatively activated macrophages via STAT6 but not IL-4Rα in vitro

•RTsP53 has regulatory effects on murine peritoneal macrophages in vitro.•RTsP53 can inhibit inflammatory factors on macrophages by inducing macrophages to alternative activation.•The effect of rTsP53 on macrophages is dependent on STAT6 not IL-4Rα.

Classically activated macrophages (M1) or alternatively activated macrophages (M2) have different functions during helminth infections including Trichinella spiralis (T. spiralis). The excretory/secretory antigens (ESA) of T. spiralis can inhibit macrophage pro-inflammatory cytokines production. However, the specific molecules of ESA that regulate macrophages have not been identified. We previously reported that recombinant T. spiralis derived molecule 53-kDa protein (rTsP53) had protected mice from colitis. Furthermore, in the present study in vitro, we investigated rTsP53 showed anti-inflammatory function by inducing peritoneal macrophages to M2 with expressing M2 molecules of mannose receptor (MR), a novel mammalian lectin (Ym1), arginase-1 (Arg1), and interleukin (IL)-10. Next, we found the effect of rTsP53 on M2 independently of IL-4Rα. But rTsP53 can act dependently on signal transducers and activators of transcription 6 (STAT6). These results further imply that rTsP53 has potential as prospective immuno-therapeutics for inflammatory disorders.