The CD8+ T cell compartment evolves during the indeterminate stage of chronic Chagas disease in a length of infection-dependent manner.

ALBAREDA MC; OLIVERA C; HERNANDEZ Y; LAUCELLA S; TARLETON R; POSTAN M

Santa Fe, New Mexico, EEUU

Simposio; Immunologic Memory, Keystone Symposia; 2007

Previous studies from our laboratories have shown that the frequency of CD27+CD28+ T cells in the total “memory” CD8+ T cell compartment of >30 year-old T. cruzi-infected subjects decreases as disease becomes more severe (Albareda et al, Int Imm 2006). Also, we demonstrated that the percentage of “naïve” CD8+ T cells (CD45RA+CD27+CD28+) is significantly lower and the percentage of “effector” CD8+ T cells (CD45RA+CD27-CD28-) higher in this group of infected subjects compared to non-infected controls. Since the infection is generally acquired during childhood, and chronic chagasic heart disease becomes clinically manifest during or after the fourth decade of life, we sought to extend our study of the “naïve”, “memory” and “effector” CD8+ T cell profile to earlier points of the indeterminate phase of the infection. Here we describe the analysis of the expression of CD45RA, CD27, CD28 and CCR7 surface markers on PBMC from twelve