Lymph node expansion of CD4+ lymphocytes during antiretroviral therapy.

The evolution of lymphocyte subsets was analyzed in sequential lymph nodes (LN) biopsies and compared with that in the blood of 25 human immunodeficiency virus type 1 (HIV-1)-infected patients receiving highly active antiretroviral therapy. An average of 3 biopsies were obtained from each patient, with a mean follow-up of 5.6 +/- 0.6 months. A correlation was found between the CD4:CD8 ratio in blood and in LN at baseline but not after > or = 2 months of therapy. With therapy, there was a significant increase in CD2+ cells and a much higher CD4+ cell increase and CD8+ cell decrease in LNs compared with levels in blood. A subset of patients had increased expression of Ki-67 and a decreased expression of CD8CD38 or CD3HLA-DR. Expanded CD4+ cells in LNs were mainly CD45RO+, and changes were concomitant with a decrease in LN virus load. These data demonstrate that CD4 cell reconstitution in HIV-1 infection takes place primarily in secondary lymphoid organs and is not related to a simple redistribution of cells.