Figure 3. IL-6-mediated increase in mitochondrial membrane potential in CD4 cells is uncoupled from OXPHOS.
(A) Intracellular ATP levels (per 104 cells) in CD4 cells activated in the presence (IL-6) of absence of IL-6 (Med) (n = 5). (B) Extracellular ATP levels in supernatants of CD4 cells activated for 48 hr (n = 3). (C) Oxygen consumption rates in CD4 cells activated with or without IL-6 for 48 hr, under basal conditions and in response to oligomycin (oligo), FCCP or rotenone plus antimycin (R/A). Average of basal level OCR (n = 3) and the average of maximal OCR (n = 3) are shown. (D) Lactate levels in supernatant of CD4 cells activated for 48 hr (n = 3). (E) Extracellular acidification rates (ECAR) were measured in activated CD4 cells (48 hr) under basal conditions or in response to glucose, FCCP or 2-deoxyglucose (2-DG) sequentially. Average of basal ECAR levels are graphed on the right (n = 3). Error bars represent mean ± SD. No statistically significant differences (p > 0.05) were found for any of the assays, as determined by Student's t-test or two-way ANOVA. Results are representative of 2–3 experiments.