ANTIMICROBIAL ACTION OF ANTIBODIES AGAINST GIARDIA-MURIS TROPHOZOITES

The activities of immune serum and trophozoite-specific MoAb were exam ined in vitro and in vivo. Immune serum and anti-Giardia muris MoAb ca used immobilization of the trophozoites in vitro and were cytotoxic fo r trophozoites in the presence of exogenous complement. Both immune se rum obtained from experimentally infected mice and anti-G. muris MoAb administered directly into the duodenum of mice significantly reduced the number of trophozoites in the small intestine during the acute pha se of the infection. These results suggest that serum antibodies play a central role in the elimination of the primary Giardia infection.