Immunogenicity of Leptospiral Vaccines Grown in Protein-free Medium

Abstract

Leptospira interrogans serovars pomona and hardjo were adapted to grow in a chemically-defined, protein-free (PF) medium. Formolised monovalent vaccines of serovars pomona and hardjo and a bivalent mixture of the two were prepared from PF cultures. Live PF cultures and the vaccine preparations retained their agglutinating antigens and their immunogenicity when tested in rabbits and guinea-pigs. The vaccines were not pyrogenic and dermal reactions were slight.