Background and Aims: During atherosclerosis, activated vascular cells secrete chemokines to recruit leukocytes to the subendothelial space. Activated leukocytes, in particular activated T lymphocytes express IFN-γ, which affects the expression of numerous genes, including the antiviral protein viperin, in vascular cells. Viperin is expressed in endothelial cells of human carotid plaques but its relevance for vascular physiology and/or pathophysiology has not been established (Olofsson et al., 2005). We aimed at studying the function of viperin in human AoSMCs.
Methods: Immunostaining of human carotid plaques was performed to determine the expression and localization of viperin in carotid plaques. To study the role of viperin in regulation of vascular inflammation, viperin was silenced using siRNA in cultured human AoSMCs, prior to stimulation with IFN-γ. Release of inflammatory mediators was analyzed using OLINK proteomics and ELISA, and the gene expression was analyzed by qRT-PCR.
Results: Viperin is expressed in endothelial cells, macrophages and smooth muscle cells in human carotid plaques. OLINK data analysis revealed reduction in release of CCL3, CXCL9, CXCL10 and CXCL11 by AoSMCs that were targeted with anti-viperin siRNA prior to stimulation with IFN-γ. Using ELISA and qRT-PCR, we could confirm the reduction of IFN-γ-induced CXCL10 and CXCL11 in viperin knockdown AoSMCs.
Conclusions: Viperin is expressed in human carotid plaques and seem to be involved in regulating the expression of CXCL10 and CXCL11 in AoSMCs. Thus, it may play a role in recruitment of T lymphocytes to the subendothelial space in atherosclerotic plaques.
Elsevier, 2021. Vol. 331, p. E88-E88