The MVA vector expressing the F protein of bovine respiratory syncytial virus is immunogenic in systemic and mucosal immunization routes

Bovine respiratory syncytial virus (BRSV), a member of the Pneumoviridae family, affects both the dairy and beef industry. The disease has a morbidity of 60-80% and mortality rate of about 20%; mainly affecting calves. The disease is spread via direct contact between the infected and the non-infected cattle and predispose the affected animals to secondary bacterial infections resulting in serious pneumonia. Because of its direct and indirect impact on the cattle industry, vaccines have been developed against the disease. However, there is failure to provide complete immunity because they usually interfere with maternal antibodies in calves and also result in severe enhanced respiratory disease. This study focused on developing a vaccine- the Modified vaccinia virus Ankara (MVA) expressing the fusion, F, protein of the BRSV virus using the Balb/C mice as the model. The vaccine was developed by transfecting the transfer vector containing the F protein of the BRSV into chicken embryo fibroblasts containing the MVA. Two routes of administration were employed in the study: intraperitoneal, in which both MVA-F homologous and heterologous vaccines were used and the intranasal (IN) route. The results of the study showed that IN administration of the MVA-F vaccine causes significant production of anti-BRSV IgA both in nasal mucosal washings and serum compared to the control group. Intraperitoneal administration of the MVA-F vaccine also yields significant anti-BRSV antigens and IFN-γ. These results indicate that when we combine the intranasal and intaperitoneal administration of MVA-F vaccine, there is both local and systemic immune responses which could potentially confer protection against BRSV
(WWN)