IMMUNOGENICITY OF VIBRIO-CHOLERAE O1 FIMBRIAE IN ANIMAL AND HUMAN CHOLERA

Parenteral immunization with either formalin-fixed whole cells of the fimbriate Bgd17 strain or purified fimbriae protected against Vibrio c holerae O1 infection in rabbits, independent of biotype and serotype. Parenteral immunization of adult rabbits with purified fimbriae prior to V. cholerae O1 challenge resulted in a reduction of 2 to 3 orders o f magnitude in the number of bacteria recovered from the small intesti nes of immunized rabbits in comparison to non-immunized controls. IgG and IgA antibodies against fimbrillin of V. cholerae O1 were detected in the convalescent sera of patients with cholera; however, little fim brial antigen was detected in the commercially available cholera vacci nes when examined by polyclonal and monoclonal antibodies against fimb riae. These data suggest that fimbrial hemagglutinin is a major adhesi n of V. cholerae O1 and that parenteral immunization with fimbriae gen erates a specific immune response in the gut that may serve as one mea ns of mitigating subsequent V. cholerae O1 gut infection.