Secretory/excretory antigens produced by tetrathyridia of Mesocestoides corti defined by SDS--PAGE and HPLC.

Antigens derived from culture medium in which metacestodes of Mesocestoides corti Hoeppli, 1925, had been maintained were studied by sodium-dodecyl-sulfate--polyacrylamide gel electrophoresis (SDS--PAGE) and high performance liquid chromatography (HPLC). By SDS--PAGE a minimum of 18 Coomassie-staining bands were discerned, of which 4 major bands and 4 major peaks by HPLC of similar molecular weights were observed. The HPLC eluate peaks were analyzed for antigenic activity in vitro by double diffusion in two dimensions, and in vivo in a rabbit. The rabbit had been artificially sensitized with a dialyzable leukocyte extract, showing transfer-factor-like activity, from peritoneal exudate cells removed from mice infected with tetrathyridia. All of the HPLC fractions reacted with rabbit antibody prepared against secretory/excretory antigens, but the sensitized rabbit responded only to two fractions. It is now possible by HPLC to fractionate complex antigens without denaturing them and to elucidate further the role they play during infection.