Clonal Hematopoiesis: Connecting Aging and Inflammation in Atherosclerosis

Purpose of Review Clonal hematopoiesis (CH) is a prevalent condition that results from the acquisition of somatic mutations in hematopoietic stem cells. When these mutations occur in “driver” genes, they can potentially confer fitness advantages to the cell, leading to a clonal expansion. While most clonal expansions of mutant cells are generally considered to be asymptomatic since they do not impact overall blood cell numbers, CH carriers display long-term risks of all-cause mortality and age-associated diseases including cardiovascular disease (CVD). This review summarizes recent findings in CH related to aging, atherosclerotic CVD, and inflammation, emphasizing epidemiological and mechanistic studies, and potential therapeutic options to treat CVDs that are promoted by CH. Recent Findings Epidemiological studies have revealed associations between CH and CVDs. Experimental studies with CH models employing the Tet2 - and Jak2 -mutant mouse lines display inflammasome activation and a chronic inflammatory state that leads to accelerated atherosclerotic lesion growth. Summary A body of evidence suggests that CH represents a new causal risk factor for CVD. Studies also indicate that understanding an individual’s CH status could provide guidance for personalized approaches to treat atherosclerosis and other CVDs with anti-inflammatory drugs.