Figure 2. Production of IL-9 in VKH disease. Production of IL-9 by peripheral blood mononuclear cells and CD4+ T cells from normal controls (n = 13), patients with inactive Vogt-Koyanagi-Harada (VKH; n = 15) disease, and patients with active VKH disease (n = 15), as measured with enzyme-linked immunosorbent assay.