Reduction in interleukin-2-producing cells but not Th1 to Th2 shift in moderate and advanced stages of human immunodeficiency virus type-1-infection:Direct analysis of intracellular cytokine concentrations in CD4(+) CD8(-) T cells

Previous studies have suggested that CD4(+)T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a mod ified method that allowed a direct measurement of intracellular cytokines i n CD4(+) CD8(-) cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uni nfected (HIV-) individuals were studied. The percentages of CD4(+) CD8(-) T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interl eukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6 % versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1.2% v ersus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm(3), 200-500/mm(3), and > 500/mm(3) to 18.0%, 23.5%, and 30.5%, P<0.05, respectively). There wa s an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r=-0.446, P<0.05). However, the percentages of CD4(+)CD 8(-) T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing c ells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection.