CONICET | Buscador de Institutos y Recursos Humanos

Bovine Respiratory Disease (BRD) is a multi-factorial disease that causes high morbidity and mortality in cattle. The disease involves a sequential cascade of events initiated by stress; thus, predisposing animals to viral infections which facilitate rapid bacterial invasionfrom the upper respiratory tract to lungs. Among bacteria causingBRD Mannheimia haemolytica (MH), Pasteurella multocida (PM)and Histophilus somni are the most important. Although BRD vaccinesare worldwide produced and applied, there is a need of newtherapeutic-adjuvant strategies in order to minimize the economicimpact of respiratory syndrome.Montanide Gel 01 is a polymeric adjuvant, based on a dispersionof stable gel particles of sodium polyacrylate in water, which enhancethe immune response by an antigen sustained release andactivation of innate immune cells.The aim of this work was study the action Montanide Gel 01 (Seppic),when it is employed in the BALB/c mice immunization with MHand PM, both bacteria causing BRD. Mice were subcutaneously immunizedon days 0, 15 and 27 with inactivated MH or PM formulatedwith Montanide Gel 01 at 5% or 10%, or with aluminum hydroxide(AH). Commercial vaccine was employed as positive control. Controlmice received the adjuvants with PBS. Blood samples were obtainedon days 0, 10, 27 and 38 and serum anti-PM and anti-MHIgG, IgG1, and IgG2a levels were measured by in house indirect ELISA.Montanide Gel 01 induced an increase in the anti-MH IgG, IgG1and IgG2a levels compared with AH vaccine (p< 0.0001; p< 0.001;p< 0.01, respectively). In relation with anti-PM antibodies, IgG2alevels were higher than the commercial vaccine (p< 0.001). SpecificIgG and IgG1 levels showed the same tendency although no significantdifferences were found.To conclude, Montanide Gel 01 induced a strong humoral immuneresponse. Further studies in cattle will allow us analyze MontanideGel 01 as a possible adjuvant candidate to use in BRD vaccines.