Evaluation of the immunogenicity of the recombinant protein GSTMu of Fasciola hepatica (rFhGSTMu) adsorbed on aluminum hydroxide in sheep

Abstract

Fasciola hepatica is a zoonosis which causes significant economic losses in ruminants. The development of a vaccine emerges as an alternative for the control of this disease. The recombinant protein GST Mu from F. hepatica (rFhGSTMu) adsorbed on aluminum hydroxide (rGSTMu + Al (OH)3) conferred 90% protection against this parasite in the mouse model. The objective of this work was to evaluate the humoral and cellular immune response against this vaccine in the susceptible species. Corriedale female sheeps were immunized twice every 30 days. The humoral immune response was analyzed by an indirect ELISA. Blood was obtained every 15 days from day 0 to 75. The in vivo immune cell response was evaluated on the day by performing the intradermal test with rFhGSTMu.Specific serum IgG antibodies increased after each boost unlike that observed in the control group (without immunization),which maintained baseline levels throughout the trial. The differences were maximum and significative (p <0.05) two weeks after the last immunization. The presence of a cellular immune response was not detected in vivo. This preliminary result indicates that rGSTMu + Al (OH)3 is immunogenic in sheep. In the future, we will evaluate the protection conferred against F. hepatica in sheep.