Further Studies on Acquired Resistance to Murine Cryptococcosis: Enhancing Effect of Bordetella Pertussis

Abstract

The adjuvant effects of Bordetella pertussis and Freund's adjuvant were compared in mice vaccinated with killed cryptococcus cells. B. pertussis greatly enhanced the immune response, causing the survival rate to increase from the 65 to 70% observed in mice immunized with cryptococcus cells alone to 95 to 100% in animals treated with both cryptococcus and pertussis vaccines. In contrast, Freund's complete adjuvant actually decreased the response to cryptococcus vaccine. Tests for antibodies in pooled sera collected at intervals following immunization with cryptococcus plus pertussis vaccine or with cryptococcus cells alone were uniformly negative. Actively immunized mice with no demonstrable humoral antibodies inhibited fungal cell multiplication in their tissues more successfully than passively immunized mice with measureable amounts of serum agglutinins. These findings suggest that the protective mechanism in mice actively immunized by these procedures exists primarily at the cellular level.