Expression of KLRG1 in human PBL.

(A) PBLs from a representative healthy donor were doubly stained with mAb specific for KLRG1 and CD8, CD4, CD16, or CD19. (B) Coexpression of KLRG1 versus CD45RA, CD28, CD62L, and CD11a gated on CD8 and CD4 T cells. (C) Percentages of KLRG1⁺ cells in the indicated cell subsets of healthy adult donors (20 to 40 years of age). Each symbol represents the value from one donor. (D) CD4 T cells were analyzed for coexpression of KLRG1, CCR4 and CXCR3. The plot shows percentages of KLRG1⁺ cells in the Th1-biased CCR4 CXCR3⁺ and the Th2-biased (CCR4⁺CXCR3) cell populations. Each symbol represents the value from one donor. (E) KLRG1 versus intracellular IL-4 and IFN-γ staining gated on CD45RO⁺ memory T cells. PBLs were activated by PMA and ionomycin for 4 hours before cytokine analysis. (F) KLRG1 expression on NK cells. PBLs were triple-stained with mAbs specific for CD3, CD56, and KLRG1. The dot plot displays KLRG1 versus CD56 expression gated on CD3⁻ PBLs.