Analysis of HIV-1- and CMV-specific IFN-γ-secreting CD4 T cells in HIV-1-infected progressors, LTNPs, and HIV-negative subjects. (A) Flow cytometry profiles of HIV-1- and CMV-specific IFN-γ-secreting CD4 T cells in the blood and lymph nodes of representative progressors and LTNPs. Blood and lymph node mononuclear cells were stimulated either with p55 gag HIV-1 protein or with CMV lysate, stained with anti-CD4 PerCp Cy5.5, anti-CD69 FITC, and anti-IFN-γ APC and analyzed by flow cytometry. The cluster of events shown in red corresponds to the responder CD4 T cells, ie, coexpressing CD69 and IFN-γ, whereas the cluster of events in blue corresponds to the nonresponder CD4 T cells. Data are expressed as the percentage of cells coexpressing IFN-γ and CD69 within CD4 T cells. (B) Mean ± SE of cumulative data on the percentage of HIV-1- and CMV-specific IFN-γ-secreting CD4 T cells in blood and lymph node of progressors, LTNPs, and HIV-negative subjects. In HIV-1-infected subjects, IFN-γ-secreting cells were assessed in blood and lymph node mononuclear cells obtained at the same time point. In the case of progressors, the cell samples analyzed were collected at study entry prior to the initiation of antiviral therapy. At least 1 × 106 events were analyzed.
