Recombinant baculoviruses as vehicles for presentation and adjuvancy of antigens for the development of new tuberculosis candidate vaccines

Recent studies have shown adjuvant properties of baculovirus by enhancing and modulating the immune response in mammals. This ability has been explained in part by the activation of the innate immunity. In addition, baculovirus induce a vigorous cytotoxic response characterized by a large number of IFNγ-producing cells. By flow cytometry analysis, we demonstrated that, when inoculated in mice, wild type baculovirus induce IFNγ and IL-12 expression and activation of NK and NKT cells.By manipulating baculovirus’ genome via homologous recombination it is possible to display multiple copies of heterologous polypeptides on the surface in a multimeric way. So, the same particle could act as both a multimeric antigen presentation structure and a potent adjuvant. As an effective immune response against tuberculosis infection is believed to primarily rely on the development of T helper 1 (Th1)-biased and cytotoxic responses, here we developed a recombinant baculovirus by engineering its genome in order to display polypeptide 85A from Mycobacterium tuberculosis on the surface of baculovirus. Thus, we combined the immunogenic advantages of baculovirus and the antigenic features of 85A antigen for the design of novel tuberculosis vaccine candidates.