Specific pathological features of IFN-associated microangiopathy are seen in patient renal biopsy material and are mediated through the type I IFN receptor. (A-B) Microvascular pathology identified in this model includes specific pathological abnormalities such as luminal narrowing (black arrows), endothelial hyperplasia (green arrows), and microaneurysm formation (blue arrows), which were seen in the biopsies of the patients described previously. Bars represent 20 μm. (C) Upregulation of IRGs (Isg15, Irf7, Cxcl10) was observed in IFN^High transgenic mice and absent in mice that lack the type I IFN receptor (IFN^High × IFNAR^−/−). Total RNA was extracted from the brain of WT and transgenic mice and analyzed by ribonuclease protection assay and visualized by autoradiography (n = 3 per group). (D) Rescue of microvascular pathology in IFN^High mice that lack the type I IFN receptor (IFN^High× IFNAR^−/−). Data represent mean ± SEM; ***P < .001, Student t test compared with IFN^High; n = 8 regions.