Decoding the immune checkpoint signatures in human atherosclerosis: implications of type 2 diabetes and lipid-lowering intervention [Human_coronary_plaque_scRNA]

Immune checkpoint inhibitor (ICI) therapies in cancer accelerate atherosclerosis progression. Here, we have charted the landscape of immune checkpoint gene expression and defined the network of disease-relevant interactions with single-cell resolution. We found that signaling through PD-1 and CTLA4 is driven by a population of dendritic cells enriched for FSCN1 that can be derived from peripheral blood cells following anti-PD-1 or -CTLA4 treatment ex vivo. Type 2 diabetes dampened plaque PD-1 and CTLA4 signaling, showing that cardiometabolic comorbidities elicit unique responses to ICIs. Lipid-lowering therapy equalized the intensity and direction of immune checkpoint interactions in human blood, while atherosclerotic mice subjected to a lipid-lowering diet displayed both increased co-inhibitory signaling and a downregulation of inflammatory transcriptional programs in plaques. Our findings underscore the potential of lipid-lowering therapies in stabilizing immune checkpoint interactions and reducing plaque inflammation, offering new insights on atherosclerosis and cardiovascular risks in cancer patients undergoing ICI treatments. Left and right anterior descending arteries were washed, minced, and digested then filtered using cell strainers. Following a dead cell removal step, single-cell suspensions were counted and loaded onto a Chromium Controller (10x Genomics).