Elevated expression of type I IFN-regulated genes in DM. Shown in the left panel are the expression patterns of 315 IFN-regulated genes (rows) in 12 DM patients (red bars) and 15 controls (gray bars). Green bars on the right indicate genes that belong to the peripheral blood IFN signature in SLE patients. The right panel shows the expression levels of these genes in control donor PBMCs treated for 6 h in vitro with IFN-α/β or PBS control. Expression data are shown as log2 ratios relative to the mean expression of control subjects (left panel) or PBS-treated controls (right panel) according to the color key provided in Figure 1.