Abstract
Murine monoclonal antibodies (MoAbs) against Echinococcus multilocularis adult worms were produced and characterized. Eleven MonAbs were obtained, of which, six were IgM (designated as EmA1, EmA2, EmA3, EmA4, EmA5, and EmA6) and five were IgG (EmA7, EmA8, EmA9, EmA10 and EmA11). The MoAbs were tested by indirect immunoperoxidase tissue staining (IP) using paraffin embedded sections of E. multilocularis adult worms. The MoAbs were classified into 7 types based on tissue staining pattern. All the MoAbs were also tested by ELISA against the antigens of E. multilocularis adult worms, metacestodes and other helminth parasites, such as Taenia taeniaeformis, T. crassiceps, T. hydatigena, Spirometra erinaceieuropaei, Hymenolepis diminuta and Toxocara canis adult worms. EmA9 reacted only E. multilocularis adult worm antigen. Since EmA9 recognized antigens of the tegument and excretory canal of the worm, as well as host intestinal epithelium around the worms by IP, it is suggested that EmA9 recognized the excretory/secretory (E/S) antigens of the worm. Sandwich ELISA using rabbit polyclonal antibodies against somatic antigens of E. multilocularis adult worms and EmA9 was performed to detect the E/S products in feces, i.e. coproantigens, of experimentally infected dogs. In three infected dogs, the coproantigens were detected as early as 3 days postinfection (PI) and continued to be positive until autopsy day 20 PI.
Key words: Echinocuccus multilocularis; monoclonal antibody; coproantigen; ELISA; immunodiagnosis.