An immunochemical method for fingerprinting Clostridium difficile.

The use of sodium dodecyl sulphate-polyacrylamide gel electrophoresis in association with electrophoretic transfer of proteins to nitrocellulose and subsequent probing with antisera appears useful as a method for fingerprinting Clostridium difficile. Thorough testing of the stability of the antigenic nature of isolates of the organism during subculture and antigen preparation has shown it to be remarkably stable both in vitro and in vivo. Minor differences in the method of antigen extraction do not markedly alter the immunoblot patterns produced. It has also been demonstrated that an individual may harbour more than one strain of the organism at any one time. Results show the possible usefulness of this technique in studying the epidemiology of diarrhoeal disease known to be associated with C. difficile. It is suggested that for any serious study several colonies should be subcultured from the primary isolation plate.