Immunogenic, non-infectious polio subviral particles synthesized in Saccharomyces cerevisiae

Polioviral genes coding for P1, the precursor for the structural proteins, and 3CD, the viral protease, were cloned in a Saccharomyces cerevisiae inducible expression system. N-antigenic empty capsids could be isolated from the yeast cell extract provided that pirodavir, a capsid-binding compound and capsid stabilizer, was added during the induction period and during purification. Purification was by immunoaffinity chromatography. The purified empty capsids had the same immunogenicity as poliovirus virions. The techniques described might be useful for the production of new non-infectious vaccines.