Engineering parvovirus-like particles for the induction of B-cell, CD4(+) and CTL responses.

An antigen delivery system based on hybrid recombinant parvovirus-like particles (VLPs) formed by the self-assembly of the capsid VP2 protein of porcine (PPV) or canine parvovirus (CPV) expressed in insect cells with the baculovirus system has been developed. PPV:VLPs containing a CD8(+) epitope from the LCMV nucleoprotein evoked a potent CTL response and were able to protect mice against a lethal infection with the virus. Also, PPV:VLPs containing the C3:T epitope from poliovirus elicited a CD4(+)3 log(10) units) against poliovirus. The possibility of combining different types of epitopes in different positions of a single particle to stimulate different branches of the immune system paves the way to the production of more potent vaccines in a simple and cheap way.