Immune response induced by conjunctival immunization with polymeric antigen BLSOmp31 using a thermoresponsive and mucoadhesive in situ gel as vaccine delivery system for prevention of ovine brucellosis

DÍAZ A; QUINTEROS D; GUTIÉRREZ S; M. RIVERO; PALMA S; ALLEMANDI D; PARDO R; ZYLBERMAN V; FERNANDO GOLDBAUM; ESTEIN S

VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 178 p. 50 - 56

0165-2427

Control of ovine brucellosis with subcellular vaccines can solve some drawbacks associated with the useof Brucella melitensis Rev.1. Previous studies have demonstrated that the polymeric antigen BLSOmp31administered by parenteral route was immunogenic and conferred significant protection against B. ovisin rams. Immunization with BLSOmp31 by conjunctival route could be efficient for the induction ofmucosal and systemic immune responses. In this work, we evaluated the conjunctival immunizationusing a thermoresponsive and mucoadhesive in situ gel composed of Poloxamer 407 (P407) and chitosan(Ch) as vaccine delivery system for BLSOmp31 in rams. Serum samples, saliva, lacrimal, preputial andnasal secretions were analyzed to measure specific IgG and IgA antibodies. Cellular immune responsewas evaluated in vivo and in vitro. Immunization with BLSOmp31-P407-Ch induced high IgG antibodylevels in serum and preputial secretions which remained at similar levels until the end of the experiment.Levels of IgG in saliva, lacrimal and nasal secretions were also higher compared to unvaccinated controlgroup but decreased more rapidly. IgA antibodies were only detected in nasal and preputial secretions.BLSOmp31-P407-Ch stimulated a significant cellular immune response in vivo and in vitro. The inductionof systemic and local immune responses indicates a promising potential of P407-Ch for the delivery ofBLSOmp31 by conjunctival route.