Mucosal immunization with polymeric antigen BLSOmp31 using alternative delivery systems against Brucella ovis in rams

DÍAZ A; QUINTEROS D; PAOLICCHI F; M. RIVERO; PALMA S; PARDO R; CLAUSSE M; ZYLBERMAN V; FERNANDO GOLDBAUM; ESTEIN

VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019 vol. 209 p. 70 - 77

0165-2427

Subcellular vaccines against ovine contagious epididymitis due Brucella ovis can solve some3 shortcomings associated with the use of Brucella melitensis Rev 1. We have demonstrated that the4 parenteral immunization with polymeric antigen BLSOmp31 emulsified in oil adjuvant conferred5 significant protection against B. ovis in rams. In our previous studies, we have characterized6 chitosan microspheres (ChMs) and a thermoresponsive and mucoadhesive in situ gel (Poloxamer7 407-Ch) as two novel formulation strategies for the delivery of BLSOmp31 in nasal as well as8 conjunctival mucosa. In the present work, we evaluated the immunogenicity and protection9 conferred by the intranasal and conjunctival immunization with these two mucosal delivery systems10 against B. ovis in rams. BLSOmp31-ChM administered by intranasal route and BLSOmp31-P407-11 Ch applied by intranasal or conjunctival routes induced systemic, local and preputial IgG and IgA12 antibody response. Neither formulation showed interference in the serological diagnosis. Thus,13 mucosal immunization using either formulation induced significant specific cellular immune14 responses (in vitro and in vivo) and it prevented the excretion of B. ovis in semen. Although these15 vaccines did not prevent infection in immunized rams, colonization reduction of infected organs and16 bacterial distribution differed significantly between vaccinated and unvaccinated rams