Modulation of ROS production by cytokines. ROS production by T cells isolated from three healthy controls (A) and three SSc patients (B) and treated with IL-1 (10 ng/ml), IL-4 (15 ng/ml), IL-6 (5 ng/ml), IL-13 (50 ng/ml), IFNα (0.5 ng/ml), TNFα (1 ng/ml), TGFβ (1 ng/ml), and PDGF-BB (15 ng/ml) for 15 minutes. Cells were then stained with 20 μM DCFH-DA and analyzed in a plate reader fluorimeter. Data are means ± standard deviation (SD) of three independent experiments with cells from three distinct subjects. *
P <0.05 compared to untreated T cells. DCFH-DA, 2′, 7′-dichlorodihydrofluorescin diacetate; IFNα, interferon alpha; IL, interleukin; PDGF-BB, platelet-derived growth factor beta; ROS, reactive oxygen species; SSc, systemic sclerosis; Th, T helper; TGFβ, transforming growth factor beta; TNFα, tumor necrosis factor alpha.