ENGINEERING POLIOVIRUS AS A VACCINE VECTOR FOR THE EXPRESSION OF DIVERSE ANTIGENS

As a step toward developing poliovirus as a vaccine vector, poliovirus recombinants were constructed by fusing exogenous peptides (up to 400 amino acids) and an artificial cleavage site for viral protease 3C(pr o) to the amino terminus of the viral polyprotein. Viral replication p roceeded normally. An extended polyprotein was produced in infected ce lls and proteolytically processed into the complete array of viral pro teins plus the foreign peptide, which was excluded from mature virions . The recombinants retained exogenous sequences through successive rou nds of replication in culture and in vivo. Infection of animals with r ecombinants elicited a humoral immune response to the foreign peptides .