Common antigens of human intestinal treponemes and of swine Treponema hyodysenteriae.

: The antigenic cross-reactivity between intestinal treponemes of human and swine origin (T. hyodysenteriae and T. innocens) was studied by sodium-dodecylsulfate-polyacrylamide gel electrophoresis and western blotting techniques. Several distinct peptides, ranging in molecular weight from 14,400 to about 150,000 daltons, were recognized by SDS-PAGE analysis of twelve human and two swine hemolytic intestinal treponemes. Thirty antigenic bands were develope by homologous antiserum against treponeme D87, one of 12 human intestinal hemolytic treponemes isolated in our laboratory. An identical number of cross-reacting antigens was found when Western blots of human treponemes D87 were tested with antisera against ten other human treponemes or with antisera against swine treponemes (T. hyodysenteriae, T. innocens). Similar results were obtained when Western blots of swine T. hyodysenteriae were tested for cross-reactivity with antisera against all human intestinal treponemes.