Carotid Plaque‐Derived Small Extracellular Vesicles Mediate Atherosclerosis and Correlate With Plaque Vulnerability

ABSTRACT Carotid plaque‐derived small extracellular vesicles (psEVs) offer insights into tissue‐ and disease‐specific pathobiology, but their roles in plaque vulnerability and their diagnostic potential remain unclear. Herein, we isolated psEVs from stable and vulnerable (intraplaque hemorrhage [IPH] or fibrous cap rupture [FCR]) plaques in patients with asymptomatic carotid artery stenosis (aCAS). Our findings demonstrated that psEVs alone were sufficient to induce inflammatory endothelial dysfunction in vitro and exacerbate atherogenesis in ApoE‐deficient mice. MicroRNA sequencing of psEVs (sequencing cohort, n = 18) identified 21 differentially expressed microRNAs (DEmiRNAs) distinguishing stable and vulnerable plaques, and 41 DEmiRNAs differentiating IPH from FCR subtypes. Subsequent validation using qRT‐PCR and the High‐throughput nano‐bio chip integrated system for liquid biopsy system revealed that plasma‐derived sEV miR‐497‐5p, miR‐152‐3p, and miR‐204‐5p effectively differentiated stable plaques from vulnerable plaques, while miR‐23a‐3p and miR‐143‐5p further distinguished IPH from FCR subtypes, in both the discovery cohort (n = 178) and an independent external cohort (n = 82). Mechanistic investigations identified miR‐497‐5p as a key mediator of vulnerable psEVs' proinflammatory and proatherogenic effects through directly targeting atheroprotective uncoupling protein 2 (UCP2). These findings highlight the roles of psEVs in atherogenesis and plaque vulnerability, providing valuable insights for risk stratification and therapeutic decision‐making in aCAS patients.