ABSTRACT
This study was carried out on sixty mice which were allocated in two group. Group I: included thirty mice which were splenectomized and orally inoculated with Giardia lamblia cysts. Group II: thirty intact infected mice which served as a control group. The mice in group I captured G. lamblia infection and demonstrated trophozoites in their intestinal sections when PAS (periodic acid Schiff) and IIF (indirect immunofluorescence) stains. On the other hand, intestinal sections stained with hematoxyline and eosin showed a spectrum of pathological changes with shortened fused villi, heavy lymphocytic infiltration in the lamina propria and atrophy in musculosa and ganglion cells which showed decrease in number per base of villus. The levels of antibody response measured with IIF-test showed significant decrease in group I compared with the control group. This study demonstrated the role of humoral immunity in infection with G. lamblia.
