1994 Volume 4 Issue 3 Pages 105-110
The precise reason for variability of disease spectrum in Giardia lamblia infested persons is not understood, but host immunity (especially local immunity) appears to be an important contributory factor. To study the interaction between host and the parasite in the small intestine, it is important to study the local cell mediated immune response to understand the pathophysiology of giardiasis. For this, in the present study the T-lymphocyte subsets were studied in intestines of BALB/c mice infected with different G. lamblia strains isolated from asymptomatic and symptomatic patients. An increase in percentages of CD3+ cells (Thy 1+) and B cells was observed, with a peak on 12th day post inoculation. There was also an increase in CD4+ cells (L3T4+) which reached a peak on 12th and 18th day post inoculation in mice infected with strains isolated from asymptomatic and symptomatic patients respectively. CD8+ (Lyt2+) cells were also slightly elevated and peaked at 12th and 24th day post inoculation in mice infected with asymptomatic and symptomatic strains respectively. It is therefore suggested that the increase in CD4+ cells may be beneficial to the host as it correlated directly with the elimination of the parasite and thus these cells might play an important role in pathogenesis of diarrhoea caused by this parasite.