Figure 2.

CD38-expressing CD4+/CD8+ T-cells in HIV-negative and HIV-positive patients prior to and following LPS stimulation. CD38 expression was measured on freshly ficoll-separated CD4+ and CD8+ T-cells at baseline (T0, top) and following 24- (T1, middle) and 48-hour (T2, bottom) LPS stimulation. PBMCs were cultured in medium alone (unstimulated, US) or in medium with 20 ng/mL LPS (stimulated, STIM). At T0, comparable CD4+CD38+ were detected in HIV-positive patients and controls (a); however, the former displayed markedly higher CD8+CD38+ (P = 0.05, (c)), with no differences amongst HIV-positive subgroups. At T1, a significantly lower expression of CD38 was detected on CD4+ (P = 0.02, (e)) and CD8+ cells (P = 0.05, (g)) from HIV-positive individuals despite LPS stimulation. While no differences in CD4+CD38+ were recorded amongst HIV-positive subgroups (f), CD8+CD38+ cells were significantly higher in LR and IR compared to HR (P = 0.04 for both comparisons, (h). At T2, LR presented highest CD38+CD8+ compared to HR (P = 0.01, (l)) and controls (P = 0.02, (l)) with no differences in CD4+CD38+ (j). P values in the results section refer to stimulated samples only.