A new antigenic relationship among faecal bacilli due to a common β antigen

Abstract

1. The presence of a new thermolabile an named β antigen has been demonstrated in motile and non-motile coliform, paracolon andProteusstrains, and inShigellabacilli (Sh. flexneri Sh. flexneriV1 and D19). This antigen can be frequently found in the above types.2. The characteristics of the β antigen have been described, and its dissimilarity to H, O, Vi, 2, A, B and α antigens has been established.3. A high incidence of β antibodies was demonstrated in normal human and rabbit sera.4. β strains of paracolon and coliform b injected intraperitoneally into mice were shown to be more virulent to mice than β minus forms of the same strains.5. It is suggested that unrecognized presence of β antigen in cultures and β antibody in human and rabbit sera may cause errors in bacteriological and serological diagnoses of enteric infections.