EVALUATION OF THE IMMUGENIC RESPONSE GENERATED BY A NOVEL VACCINE FORMULATION AGAINST NEOSPORA CANINUM INFECTION

BENGOA LUONI, S.; CORIGLIANO, M.; CLEMENTE, M.; SANDER, V.

Buenos Aires

Congreso; Latin American Society for Immunodeficiencies; 2015

Sociedad Argentina de Inmunologia

Background: Neosporosis is an intracellular coccidiandisease caused by Neospora caninum,the main pathogen agent responsible for economic losses in the cattle industry. There is no effective vaccine toprevent neosporosis.In this study we evaluated theimmunogenic response generated by the administration of a novel vaccineformulation including the major surface antigen of N. caninum (NcSAG1) and as adjuvant the 81 KDa heat shock protein (HSP81.2)from Arabidopsis thaliana. Methods: Both recombinant proteins werecloned and expressed in Escherichia coli,and then purified and passed through a polymixin B-agarose column to eliminateendotoxins. BALB/c female mice were intraperitoneally immunized on day 0 and 15with equimolar quantities of the recombinant proteins: rNcSAG(10 mg) alone (rNcSAG1 group) or a mixture of rNcSAG1(10 mg) and rAtHsp81.2(30 mg) (rNcSAG1+rAtHSP81.2group) in 200 ml of Phosphate Buffer Saline (PBS). Control mice wereadministered 200 ml of PBS (C group). Mice were bled on days 0,15,30,60and 120 from the tail vein to determine titers of total Immunoglobulin G(IgGt), IgG1 and IgG2a.Results: High IgGt, IgG1 and IgG2a specific antibodylevels directed against recombinant NcSAG1protein were developed by rNcSAG1+ rAtHSP81.2group from day 30 post immunization, while rNcSAG1 group showed lower titers ofIgGt and IgG1on day 30, and IgG2a antibodies were detected only from day 60post immunization. Conclusions: rNcSAG1combined with the adjuvant rAtHSP81.2was able to induce an important humoral response in immunized mice, encouragingus to determine the effectiveness of this vaccine formulation in preventing thedeleterious effects of congenital neosporosis.