Homeostasis of naive and memory T cell subpopulations in peripheral blood and lymphoid tissues in the context of human immunodeficiency virus infection

To understand the nature of naive and memory T cell depletion in human immunodeficiency virus (HIV) immunopathogenesis, their homeostasis in peripheral blood (PB) and lymph node (LN) compartments of HIV-infected patients was examined. Although the percentage of naive CD4⁺ cells was higher in LN than in PB mononuclear cells (LNMC and PBMC, respectively), the memory cells were higher in PBMC than in LNMC. The ratio of naive:memory CD4⁺ cells from PB positively correlated with that in LNs and with the absolute CD4⁺ cell counts and recall antigen responses, and the ratio inversely correlated with the cellular virus load from the corresponding compartment. These findings indicate that although the pattern of naive and memory cells in the LN and PB compartments appear divergent, their relationship is nonrandom and is significant. The naive:memory ratio in PB appears to reflect the lymphoid microenvironment and may potentially be useful as a surrogate marker for treatment efficacy and immune reconstitution.