Interferon Regulatory Factor 7 Protects Against Vascular Smooth Muscle Cell Proliferation and Neointima Formation

BackgroundInterferon regulatory factor 7 (IRF7), a member of the interferon regulatory factor family, plays important roles in innate immunity and immune cell differentiation. However, the role of IRF7 in neointima formation is currently unknown. Methods and ResultsSignificant decreases in IRF7 expression were observed in vascular smooth muscle cells (VSMCs) following carotid artery injury in vivo and platelet‐derived growth factor‐BB (PDGF‐BB) stimulation in vitro. Compared with non‐transgenic (NTG) controls, SMC‐specific IRF7 transgenic (IRF7‐TG) mice displayed reduced neointima formation and VSMC proliferation in response to carotid injury, whereas a global knockout of IRF7 (IRF7‐KO) resulted in the opposite effect. Notably, a novel IRF7‐KO rat strain was successfully generated and used to further confirm the effects of IRF7 deletion on the acceleration of intimal hyperplasia based on a balloon injury‐induced vascular lesion model. Mechanistically, IRF7's inhibition of carotid thickening and the expres...