BACKGROUND AND AIMS: Clonal haematopoiesis of indeterminate potential (CHIP) has been associated with cardiovascular risk, but its prognostic relevance and mechanistic role in coronary artery disease (CAD) remains incompletely understood. This study investigated the association between CHIP and all-cause mortality in CAD and explored the cellular and molecular mechanisms, focusing on TET2 mutations.
METHODS: Targeted deep sequencing of 13 CHIP driver genes in 8612 patients with angiographically confirmed CAD was performed. Clonal haematopoiesis of indeterminate potential carriers (variant allele frequency ≥2%) were propensity-score matched 1:1 to non-carriers. Mortality was assessed over 3 years. Mechanistic insights were derived from post-mortem high-sensitivity plaque proteomics (MISSION), RNA sequencing from carotid plaques (Athero-Express), monocyte-derived macrophage transcriptomes (STARNET), and CRISPR/Cas9-generated TET2+/- macrophages in vitro.
RESULTS: Clonal haematopoiesis of indeterminate potential was associated with increased 3-year mortality (hazard ratio 1.39, 95% confidence interval 1.16-1.65, P < .001) in 2389 matched pairs. Mutations in TET2, ASXL1, DNMT3A, JAK2, PPM1D, SF3B1, SRSF2, and U2AF1 individually conferred higher mortality risk. In human plaques, CHIP mutations were found in lesional macrophages. TET2 CHIP carriers showed increased necrotic core size, inflammation, and reduced plaque stability. Multi-omics profiling revealed up-regulation of lipid metabolism and inflammatory pathways. TET2+/- macrophages exhibited increased LDLR expression and lipid uptake, linked to enhanced chromatin accessibility at the LDLR promoter. These findings were confirmed in carotid plaques, which showed increased LDLR and inflammasome-related gene expression in TET2 CHIP carriers.
CONCLUSIONS: Clonal haematopoiesis of indeterminate potential is a predictor of mortality in CAD patients. TET2 mutations promote a pro-atherogenic macrophage phenotype via LDLR up-regulation and inflammatory activation, linking epigenetic dysregulation to adverse outcomes in CAD.
CRISPR Gene Editing