CHANGES IN T-CELL SUBPOPULATIONS IN MICE DURING PROLONGED EXPERIMENTAL SECONDARY INFECTION WITH ECHINOCOCCUS-GRANULOSUS

Balb/c mice were infected intraperitoneally with protoscoleces of Echi nococcus granulosus. After 15 months of infection, and by means of flo w cytometry, the expression of T-cell markers CD3, CD4, and CD8 on T c ells from peripheral blood, spleen, and thymus was analyzed and compar ed with that of age-matched controls. Infected mice had higher percent ages of CD3+, and CD4+ cells in peripheral blood, and higher percentag es of CD8+ cells in the spleen, when compared with control mice. CD4and CD8+ cells in peripheral blood and CD8+ cells in thymus also showe d higher percentages of expression of interleukin-2 receptor. The resu lts infer a role for interleukin-2 in experimental secondary echinococ cosis.