APOA1 and sarcoidosis: Specifically, HDLC reduces inflammation in multiple cell types including endothelial cells and macrophages by several mechanisms involving apolipoprotein A-I and cholesterol efflux [35], while hypercholesterolaemia leads to cholesterol accumulation and metabolism reprogramming in immune cells and promotes inflammatory responses [36, 37], which may account for the upstream roles of HDLC and TC in sarcoidosis found in this study.