IL-2–induced up-regulation of Bcl-2 expression is associated with protection from TNFRs-induced apoptosis.
PBMCs from an HIV-infected donor were pretreated overnight with IL-2 (50 ng/mL) or medium. Dot plots (upper part) show the influence of IL-2 on Bcl-2 and Bcl-xL expression in CD4 (A) or CD8 (B) T cells. Low, normal, and high Bcl-2 populations are shown and numbers in quadrants indicate the percentage of apoptotic cells within the corresponding Bcl-2 subset. Mean fluorescence intensity (MFI) of Bcl-xL expression on gated CD4 or CD8 T cells is indicated. These cells were further stimulated with anti-TNFR1 or anti-TNFR2 mAbs and apoptosis in each T- cell subset was quantified. The lower part of the figure shows data from experiments performed with PBMCs from 5 patients (mean ± SD). Preincubation in ░, medium; ▪, IL-2.
