Single-cell RNA sequencing reveals B cell-T cell interactions in vascular adventitia of hyperhomocysteinemia-accelerated atherosclerosis

Dear Editor Cardiovascular disease(CVD)is the leading cause of death around the world(Truelsen,et al.,2015).Atherosclerosis,the dominant underlying cause of CVD,is a chronic inflam-matory disease characterized by lipid accumulation and immune cell infiltration in plaques and vessels(Weber,et al.,1950).The immune microenvironment is critical for the development of atherosclerosis.Homocysteine(Hcy)is an intermediate product of methionine metabolism,and its ele-vation in plasma(＞15 μmol/L),known as hyperhomocys-teinemia(HHcy),is an independent risk factor for atherosclerosis.HHcy is more common in Asia because of genetic factors and dietary habits(Huo,et al.,2015).folic acid supplement is one of the most important way to treat HHcy in clinic.Although HHcy potentiates atherosclerosis mainly through endothelial injury and inflammatory activa-tion(Luo,et al.,2016),a comprehensive understanding of the immune microenvironment and potential mechanisms in HHcy-accelerated atherosclerotic aortas(HHcy-AA)is still lacking.