Functional characterization of intestinal intraepithelium & lamina propria lymphocytes from Giardia lamblia infected mice
Vinayak, V.K.; Khanna, R.; Kum, K.; Nain, C.K.
Indian Journal of Medical Research 89: 271-281
1989
ISSN/ISBN: 0019-5340 PMID: 2807433 Document Number: 339037
Quantitation of T cell subsets in intraepithelium and lamina propria during the course of experimental Giardia lamblia infection in the inbred mice revealed increased influx of Thy 1.2+ (T cells) and Lyt 2.2+ (suppressor/cytotoxic T cells) during the establishment (3-5 day post-inoculation) phases of infection. The influx of these cells reduced as the parasite load declined. In contrast, no significant changes were noticed in lamina propria and intraepithelium Lyt 1.1+ (helper T cell) cells during the establishment or acute phase but such cells increased significantly in the decline (17-21 day post-inoculation) phase of infection. Further, both intraepithelium and lamina propria lymphocytes isolated from uninfected or infected animals failed to kill G. lamblia trophozoites in vitro in the absence or presence of antigiardial antibodies. Our data suggest that the clearance of G. lamblia trophozoites was not mediated by cytotoxic T cells. However, the induction of helper T cells during the declining phase of infection might be an important mechanism for the induction of parasite specific antibody response leading to the immune elimination of G. lamblia trophozoites from the gut.