Raw data of Figs 1–9 in this study.

BackgroundA Trichinella spiralis serine proteinase (TsSPc) was identified in the intestinal infective larva (IIL) surface and excretory-secretory (ES) antigens. Our previous study showed that recombinant TsSPc (rTsSPc) disrupted intestinal epithelial integrity and barrier function, and mediated larval invasion of intestinal mucosa. This study aims to investigate the impact of rTsSPc vaccination on intestinal epithelial integrity and its elicited protective immunity in a mouse model.Methodology/principal findingELISA results demonstrated that rTsSPc immunization induced a systemic humoral immune response with serum-specific IgG antibody titer reaching 1:10⁵, and elicited a mixed Th1/Th2 immune response dominated by the Th2 type. In the rTsSPc-immunized mice, the TsSPc-specific intestinal sIgA level was also markedly increased (P P P ConclusionsrTsSPc vaccination produced a high protective immunity through multiple synergistic mechanisms: eliciting an obvious humoral and cellular immunity, gut local mucosal sIgA responses; blocking the binding of parasite-derived TsSPc to gut RACK1 receptors and the activation of MAPK/ERK1/2 pathway, improved gut epithelial integrity, inhibiting larval invasion, enhancing macrophages’ ability of ADCC killing larvae, and finally reduced parasite burden and alleviated inflammation of intestines and skeletal muscles. TsSPc might be a promising novel candidate target for anti-T. spiralis vaccine.