Fig. 1

IL-22 is produced by CD4 + T cells in healthy young children. PBMCs from healthy young children were prepared and cultured with PMA and ionomycin for 4–6 h, then cells were harvested, fixed, permeabilized, and cell surface and intracellular staining were done and determined by FACS. a IL-22 production by CD4 + T or CD3 + CD4-T cells from one representative donor was shown. Lymphocytes were first gated on CD3 + CD4 + (CD4 + T cells) or CD3 + CD4- cells and then analyzed for IL-22 production. b The statistical data results of the percentages of IL-22+ cells in CD4 + T cells or CD3 + CD4-T cells were shown (n = 9). The median is represented by horizontal line, the interquartile range by box and the minimum to maximum range by whiskers. *, p < 0.05