Echinococcus granulosus: immunoprotection accompanyied by humoral and cytokine response against secondary hydatidosis in mice immunized with rEg.myophilin.

Objects: This study aimed to investigate the immunoprotection of the recombinant Eg.myophilin (rEg.myophilin) and tentatively analyze mechanism of this protection.

Materials And Method: Three groups of female mice were immunized subcutaneously with rEg.myophilin and contrasts, after two boosters, mice were challenged with Eg protoscoleces (PSCs) intraperitoneally, and then analyzed the humoral immune response with specific IgG, IgG1, IgG2a, IgG2b, IgG3 and IgE, and also evaluated the cellular immune with IFN-γ, IL-4, IL-10.

Results: Mice immunized with rEg.myophilin produced effective immunity protection (reductions in cyst load more than 86.11%). Mice immunized with rEg.myophilin showed specific IgG, IgG1, IgG2a and IgE accompanied by IFN-γ and IL-4 significantly increased after one or more times of immunization, but neither IgG2b nor IgG3 increased. Nevertheless, IL-10 significantly increased in the control groups but a decline trend in rEg.myophilin group.

Conclusions: rEg.myophilin showed a effectively protective immunity, which may attribute to: (1) IgGs and IgE-mediated humoral immune response, as well as cell-mediated immunity which was marked by IFN-γ. (2) IL-4 assists to stimulate type transformation of IgE which plays an important role in Eosinophils-related anti-parasite immunity. (3) Immunosuppressive effect (marked by IL-10), the key obstacle to clean of parasites in the patient, was inhibited in the rEg.myophilin group compared with control groups.