Prevalence of IFN type I signature in SLE patients. (A) Heatmap showing gene expression of four IFN type I-inducible genes in monocytes of SLE patients (n = 25) and HCs (n = 15). On the left, the HCs are depicted, and on the right, the SLE patients are depicted and subdivided into IFN type I signature-positive and -negative patients. Red indicates high gene expression, and cases are depicted according to IFN scores. (B) Distribution of IFN scores in IFN type I signature-positive and -negative patients and HCs. In red, IFN type I-positive cases are depicted. Blue lines represent medians. P values are shown, and to compare medians, the Mann–Whitney U test was used.