Figure 2

CD4^pos T-cell response to cytomegalovirus (CMV) Ags in patients receiving anti-tumor necrosis factor (TNF) treatments. (a) Peripheral blood mononuclear cells (PBMCs) from CMV-seropositive patients were incubated with CMV Ags, and intracellular interferon (IFN)-γ production was measured with flow cytometry, as indicated in Materials and Methods. CD4^pos T-cell responses are represented as the percentage of IFN-γ^pos cells within the CD4^pos population. (b) PBMCs were cultured for 5 days in the presence of CMV Ags, and their proliferation was evaluated by measuring the incorporation of ³H-thymidine. The stimulation index (S.I.) was derived by dividing the cpm obtained by using CMV-Ags by those from control Ags.