Isolation and Biological Properties of Three Classes of Rabbit Antibody to Vibrio cholerae

Abstract

The three classes of rabbit immunoglobulin containing specific antibody to Vibrio cholerae were isolated in pure form. Sera from rabbits immunized parenterally with V. cholerae were used for the isolation and purification of both IgG and IgM. Only those immunization schedules confined to the oral route gave significantly elevated titers of IgA antibody in both intestinal washings and colostrum. Various tests of antibacterial efficacy were done on the purified immunoglobulins. Preparations of IgA contained little complement-mediated vibriocidal or opsonic activity. Specific IgA was a good protective antibody in the infant mouse cholera model; on the basis of weight, it protected as well as IgG and IgM.