Different gene-expression profiles between effector CD8⁺ T-cell subsets. (A) Quantitative PCR for the indicated genes up-regulated in CXCR1⁺ (left) or CXCR1⁻ (right) subsets was performed with FACS-sorted CXCR1⁺ and CXCR1⁻ cells in the effector, naive, and memory subsets. The mean relative gene-expression levels and SD from 4 healthy individuals are shown. The values on each column show the relative gene-expression ratio between the 2 subsets; left: up-regulated genes in CXCR1⁺ cells, right: those in CXCR1⁻ cells. (B) PBMCs from subject number U-43 were stimulated for 4 hours with solid-phase anti-CD3 mAb with or without STO-609. The percentage of IL-2–producing cells in the CD3⁺CD8⁺CD27⁻CD28⁻ subset is shown. (C) The same experiment as in panel B was performed with the PBMCs from 4 healthy subjects, and then the relative percentage of IL-2–producing cells was expressed as the mean and SD based on that in the condition without inhibitor. (D) The CXCR1⁺ and CXCR1⁻ cells in the CD27⁻CD28⁻ effector CD8⁺ T-cell subset were sorted and then the cells were stimulated with solid-phase anti-CD3 mAb with or without STO-609 to assess the percentage of IL-2–producing cells.