Interferon‐induced protein 35 inhibits endothelial cell proliferation, migration and re‐endothelialization of injured arteries by inhibiting the nuclear factor‐kappa B pathway

Abstract Aim Endothelial recovery, or re‐endothelialization, plays an important role in intimal hyperplasia and atherosclerosis after endothelial injury. Studying the mechanisms of re‐endothelialization and strategies to promote efficient endothelial recovery are still needed. Interferon‐induced protein 35 ( IFI 35) is an IFN ‐γ‐induced protein that plays important roles in the antivirus‐related immune‐inflammatory response. In this study, we tested whether overexpression IFI 35 affects the proliferation and migration of endothelial cells ( EC s) and re‐endothelialization. Methods Wire injury of the carotid artery was induced in C57 BL /6 mice, which was followed by IFI 35 or null adenovirus transduction. Evans blue staining and HE staining were performed to evaluate the re‐endothelialization rate and neointima formation. In vitro studies, primary human umbilical vein endothelial cells ( HUVEC s) were transfected with Ad‐ IFI 35 or si RNA ‐ IFI 35 to evaluate its potential roles in cell proliferation and migration. Furthermore, the potential mechanism relating inhibition of NF ‐κB/p65 pathway was elaborated by luciferase assay and IFI 35 domain deletion assay. Results In IFI 35 adenovirus‐transduced mice, the re‐endothelialization rates at days 3, 7 were significantly reduced compared to those in null adenovirus‐transduced mice (5% and 35%, vs 20% and 50%, respectively). Meanwhile, subsequent neointimal hyperplasia was obviously increased in IFI 35 adenovirus‐transduced mice. In vitro studies further indicated that IFI 35 inhibits both EC proliferation and migration by inhibiting the NF ‐κB/p65 pathway. Subsequent studies demonstrated that IFI 35 functionally interacted with Nmi through its NID 1 domain and that knock‐down of Nmi significantly mitigated the inhibitory effect of IFI 35 on EC proliferation and migration. Conclusion Our study revealed a novel mechanism through which IFI 35 affects the proliferation and migration of EC s as well as neointima formation, specifically through inhibition of the NF ‐κB/p65 pathway. Thus, IFI 35 is a promising target for the prevention and treatment of post‐injury vascular intimal hyperplasia.