BLS protein as BRV antigen delivery system in a suckling mice model

BELLIDO D; CRAIG PO; MOZGOVOJ MV; GONZALEZ DD; WIGDOROVITZ A; GOLDBAUM FA; DUS SANTOS MJ

Ouro Preto, Brasil

Congreso; 8th International Veterinary Immunology Symposium (IVIS); 2007

Brucella spp lumazine synthase (BLS) presents a very resistant and high order decameryc structure. It allows the fusion of  peptides in its 10 N-terminus, giving chimeric proteins with high order arrangement that are able to induce efficient immune responses. The objective of this work is to produce stable fusion proteins when bigger protein domains are inserted in the BLS structure and to evaluate the immune response induced by the chimeric protein. We believe that Bovine Rotavirus (BRV) VP8 protein is an accurate protein to be fused to BLS based on its physical, chemical and immunological properties. The inner part of VP8, VP8d, is a high structured soluble domain that preserve the sialic acid binding site and the relevant epitopes wich induce neutralizing antibodies. The present work shows that the BLS-VP8d chimera is able to efficiently stimulate the immune system. The immunological properties of the chimeric protein and its capability for inducing passive protection were tested in a suckling mice model. These results were compared with those obtained with the single VP8d protein. Dams immunized with the chimeric protein gave birth to pups that after challenge with BRV C486 [P1]G6 showed 100% protection level; on the other hand, pups born to dams immunized with VP8d presented a level of protection of 30%. The antibody pattern was also significatly different in both experimental groups, as it was evaluated by ELISA in serum and milk. .