Recombinant elongation factor 1 alpha of Haemonchus contortus affects the functions of goat PBMCs.

Excretory/secretory proteins of Haemonchus contortus (HcESPs) intermingle comprehensively with host immune cells and modulate host immune responses. In this study, H contortus ES antigen named as elongation factor 1 alpha (HcEF-1α) was cloned and expressed. The influences of recombinant HcEF-1α on multiple functions of goat peripheral blood mononuclear cells (PBMCs) were observed in vitro. Immunoblot analysis revealed that rHcEF-1α was recognized by the serum of goat infected with H contortus. Immunofluorescence analysis indicated that rHcEF-1α was bound on surface of PBMCs. Moreover, the productions of IL-4, TGF-β1, IFN-γ and IL-17 of cells were significantly modulated by the incubation with rHcEF-1α. The production of interleukin IL-10 was decreased. Cell migration, cell proliferation and cell apoptosis were significantly increased; however, nitric oxide production (NO) was significantly decreased. The MHC II molecule expression of cells incubated with rHcEF-1α was increased significantly, whereas MHC-I was not changed as compared to the control groups (PBS control and pET32a). These findings indicated that rHcEF-1α protein might play essential roles in functional regulations of HcESPs on goat PBMC and mediate the immune responses of the host during host-parasite relationship.