ANTI-CD4 CYTOTOXIC T-LYMPHOCYTE (CTL) ACTIVITY IN HIV- FLOW CYTOMETRIC ANALYSIS( PATIENTS )

A new cell proliferation analysis by flow cytometry was applied to the mitogen induced cultures of peripheral blood mononuclear cells (PBMC) from either normal, healthy donors or those individuals who are infec ted by human immunodeficiency virus, type 1 (HIV-1). While phytohemagg lutinin (PHA) stimulation of normal PBMC (nPBMC) yielded propagation o f both CD4 (nCD4) and CD8 (nCD8) T cell subsets, similar activation of PBMC from certain HIV-1-infected individuals (HIV-PBMC) produced acti ve proliferation of CD8 (HIV-CD8) cells but varying degrees of CD4 (HI V-CD4) cell destruction. However, no measurable viral p24 antigen was produced extracellularly. On the other hand, when the purified HIV-CD4 cells were similarly activated, no such cell death was noted and high titer p24 was detected in the culture supernatants. Addition of exoge nous IL-2 to either HIV-PBMC or HIV-CD4 cultures, did not alter either CD4 cell death or HIV-1 p24 production. Isolated HIV-CD8 killed not o nly HIV-CD4 but also nCD4, when co-cultured and less proliferative fra ctions of CD4 cell population was the more preferred targets of the HI V-CD8 CTL activity. The presence of anti-CD4 CTL activity was closely associated with high CD8, but not with CD4 counts, of the HIV+ patient s.