Fig 1.

CD4+ T cells producing interleukin (IL)-17, IL-22 and interferon (IFN)-γ are present in peripheral blood (upper panels) and normal dermis (lower panels). Intracellular cytokine staining and flow cytometric analysis show distinct populations of CD4+ T cells producing IL-17, IL-22 and IFN-γ in peripheral blood. In normal human dermis there are CD4+ T cells producing only IFN-γ, IL-17 or IL-22, and CD4+ T cells that cosynthesize IL-17 and IL-22, IL-17 and IFN-γ, IL-22 and IFN-γ or all three cytokines. Fluorescence-activated cell sorting plots are representative of two separate experiments. Leftmost panels are isotype controls.