IMMUNOGENICITY AND ANTIGENIC RELATIONSHIP OF SALMONELLA ENTEROTOXIN WITH OTHER ENTEROTOXINS

The immunogenicity and antigenic relationship of Salmonella enterotoxi n with other enterotoxins were studied. The purified enterotoxin of Sa lmonella typhinurium strains was immunogenic in rabbits and antiserum produced against it completely neutralized the enterotoxic activity of purified as well as crude enterotoxins. The Salmonella enterotoxin di d not cross-react with cholera toxin, heat-labile enterotoxin of Esche richia coli or Shiga toxin. On the other hand, enterotoxins produced b y different serotypes of Salmonella were antigenically related. Heat, pH and proteolytic enzymes had not only adversely affected the enterot oxigenicity but also the antigenicity of the Samonella enterotoxin. Ho wever, formalin was found to completely destroy the enterotoxigenicity of enterotoxin without affecting the antigenicity. Formalin-treated e nterotoxin may thus be tried as a vaccine to prevent the diarrhoeal sy ndrome induced by enterotoxigenic salmonellae.