Micro y manoparticulas como adyuvantes vacunales frente a al brucelosis y la salmonelosis ovina

Abstract

Brucella spp. and Salmonella Abortusovis cause major econòmic Tosses in the ovine industry causing abortions, male infertility (B. ovis and B. melitensis) and lamb mortality (S. Abortusovis). currently, the most universal system of prophylaxis used against ovine brucellosis, and the only practical measure to control the disease in countries with a high prevalence, consist of the vaccination of animals with live attenuated B. melitensis strain Revi. Thus, the control of S. Abortusovis infección is based on the subcutaneous administration of the uve attenuated S. Abortusovis strain Rv6. However, they present some drawbacks, such as the residual virulence or the interference with serological tests currently used in serodiagnosis. A new trend to minimise all of these drawbacks is based on the use of subcellular vaccines combined with controlled reléase vector adjuvants. in this context, we proposed the use of poly(-caprolactone) micróparticles, prepared by a new method named TROMS, containing an antigenic extract (HS) from B. ovis. Due to its special physico-chemical properties we evalúate the effect of several excipients on the physico-chemical and biological properties of the final product. Tne use of β-cyclodextrin in combination with Pluronic F68 (F68-CD-MP) resulted the most suitable formuiation, as a consecuence, it was assesed in a protection study against experimental infeccions with B. melitensis in balb/c mi ce and with B. ovis in rams. in both cases, the results showed that subcutaneous administration of F68-CD-MP micróparticles elicited a level of protection similar to that provided by the reference vaccine Revl. Salmonella Abortusovis is poorly studied Salmonella, whose major antigenic components have not yet been characterized. Thus, in this work we studied the use of both poly(-caprolactone) micróparticles and Gantrez® an nanoparticles preparations as adjuvants for an antigenic extract of S. Abortusovis (Hsao). Besides, experimental infection with S. Abortusovis strain 15/5 was performed in mice to establish the protective efficacy of both preparations. in the experimental conditions used, a single dose of the antigenic complex HSao incorporated in nanoparticles afforded a statistical similar level of protection to that conferred by the live Rev6 reference vaccine. in contrast, micróparticles containing the same antigenic complex were not protective.