IDEHU   05542
INSTITUTO DE ESTUDIOS DE LA INMUNIDAD HUMORAL PROF. RICARDO A. MARGNI
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Study of the immunogenicity exerted by a vaccine against Respiratory Bovine Disease in a murine model
Autor/es:
DÍAZ AILÉN; MOLINA MA; GONZÁLEZ MAGLIO D; MANGHI M; CASTRO MS
Lugar:
Los Cocos,Córdoba
Reunión:
Congreso; Reunión Anual de la SAI; 2013
Institución organizadora:
Sociedad Argentina de Inmunología
Resumen:
Respiratory Bovine Disease (RBD) affects cattle causing big economic losses. The etiologic agent is complex and includes bacteria and viruses, highlighting P. multocida (PM) as one of the main bacterial agents. The RBD vaccines used in our country do not always provide an adequate control for the disease. For this reason, it is necessary to improve and perform studies to support their potency. The aim of this work was to evaluate the humoral immune response and the protection conferred by RBD vaccination in a murine model studying the response against PM for its importance in the disease. We selected a vaccine of national production and we compared two immunization schedules. CF-1 mice were immunized and blood samples were obtained according: A) immunization at days 1 and 15, bleeding time 10 and 20; B) immunization at days 1, 4, 7, and 10, bleeding time 7 and 15. In parallel, 10 to 15 days post-last immunization, mice were challenged with an ip PM lethal dose to evaluate the protective capacity of the vaccine. Surviving animals of both schedules were bled. Specific antibody levels (IgG, IgG1, and IgG2a anti-PM) were determined by ELISA. Immunization schedules induced low specific IgG titers in both plans (A: 139,9 ± 30,12 and B: 489,5 ± 276,1). However, both schedules generated a high protection level (% survival: 90% and 100% for A and B schedules, respectively). Surviving mice showed high specific IgG levels (A: 5767 ± 1065 and B: 10510 ± 2991). In these animals, the specific IgG2a levels were higher than IgG1 anti-PM (IgG2a/IgG1 ratio for A: 8,7 ± 7,3 and for B 10,3 ± 6,4). These results indicate that immunization with a RBD vaccine protects animals from challenge with the infectious agent but such protection does not appear to be mediated by high specific IgG levels in blood. Further studies will be performed to evaluate the cellular immune response against PM as well as the other bacterial antigens.