ALTERED REPRESENTATION OF NAIVE AND MEMORY CD8 T-CELL SUBSETS IN HIV-INFECTED CHILDREN

CD8 T cells are divided into naive and memory subsets according to both function and phenotype, In HIV-negative children, the naive subset is present at high frequencies, whereas memory cells are virtually absent, Previous studies have shown that the overall number of CD8 T cells does not decrease in HIV-infected children, In studies here, we use multiparameter Bow cytometry to distinguish naive from memory CD8 T cells based on expression of CD11a, CD45RA, and CD62L, With this methodology, we show that within the CD8 T cell population, the naive subset decreases markedly (HIV+ vs, HIV-, 190 vs, 370 cells/mu l; P less than or equal to 0.003), and that there is a reciprocal increase in memory cells, such that the total CD8 T cell counts remained unchanged (800 vs. 860 cells/mu l; P less than or equal to 0.76), In addition, we show that for HIV-infected children, the naive CD8 T cell and total CD4 T cell counts correlate (chi(2)P less than or equal to 0.001), This correlated loss suggests that the loss of naive CDS T cells in HIV infection may contribute to the defects in cell-mediated immunity which become progressively worse as the HIV disease progresses and CD4 counts decrease.