Demonstration of the common antigens of Clostridium botulinum, C. sporogenes and C. novyi by an enzyme-linked immunosorbent assay and electroblot transfer.

EDTA extracts were prepared from whole cells of 16 strains of Clostridium botulinum (types A-E), 6 strains of C. novyi (types A-D) and 3 strains of C. sporogenes. They were reacted in an enzyme-linked immunosorbent assay (ELISA) with antisera raised against whole, UV-killed cells of C. sporogenes and C. novyi type A. Results showed significant cross-reactions between C. sporogenes antiserum and the C. botulinum type A (three out of four strains), proteolytic type B (all strains) and one type E strain, and between C. novyi type A antiserum and C. botulinum types C and D. All the C. sporogenes and C. novyi strains reacted with their homologous antiserum; these two species showed no cross-reactions. All the reactions were investigated further by running the EDTA extracts on SDS-polyacrylamide gels. The separated molecules were electrophoretically transferred to nitrocellulose membranes, reacted with antiserum and complexes visualized with horseradish peroxidase conjugate reagents. Only those extracts that reacted significantly in the ELISA gave a pattern of cross-reactive antigen bands and the number of bands and intensity of stain closely paralleled the strength of the ELISA reaction.