Trypanosoma cruzi: T cell subpopulations in the Peyer's patches of BALB/c infected mice.

The changes in the T cell subsets of the Peyer's patches and the thymus were analyzed in BALB/c mice infected with Trypanosoma cruzi, Tulahuén strain. During the acute stage of the infection both lymphoid organs drastically reduced their cellularity. This was mainly due to the decrease in the immature CD4+CD8+ T cell population in the thymus and in both T and B cells in the Peyer's patches. In the acute infection, few Peyer's patches were found and the histological studies revealed a depletion of the thymic-dependent areas, paralleling the decreased number of cells expressing CD4 and alpha beta T cell receptor. After 14 weeks, in the late stage of the infection, the cellularity and the levels of the T cell subsets studied returned to values similar to those of noninfected mice.