T_(TN) lymphocytes reveal distinct homing, survival, and functional properties compared with T_(TCM) and T_(TEM) cells. (A) Expression of IL-7Rα on T-cell subsets gated on CD8⁺ lymphocytes: representative FACS plot (left) and average histograms (right) including also the analysis performed on CD45RA⁺CD62L⁺ T_(TN). (B) Longitudinal analysis of cell-surface IL-7Rα expression on CD8⁺ T cells. (C) Panel of cell-surface markers analyzed on CD8⁺ T_(TN), T_(TCM), and T_(TEM) subsets. From top to bottom: CXCR4, CCR5, and HLA-DR. For each marker representative FACS plots (left) and average histograms [right, including also the analysis performed on CD45RA⁺CD62L⁺ T_(TN)] are depicted. (D) Representative FACS plots of IL-2, IFN-γ, granzyme-A, and perforin production are shown. Plots are gated on CD8⁺ cells and quadrant frequencies are indicated. (E) Quantitation of IL-2, IFN-γ, and granzyme-A production by T_(TN), T_(TCM), and T_(TEM) cells. Average percentages of CD8⁺ cytokine-producing cells are indicated. (F) Negative correlation of IFN-γ production with CD62L⁺CD45RA⁺ coexpression (top) and IL-7Rα cell-surface expression (bottom). All FACS analyses were performed 16 days after stimulation. Gray histograms represent fluorochrome-matched isotype controls. Mean data from at least 3 healthy donors are presented, and error bars represent SEM.