Immature neutrophil is associated with coronary plaque vulnerability based on optical coherence tomography analysis

High neutrophil to lymphocyte ratio is considered to predict poor prognosis of acute coronary syndrome (ACS). However, the association of neutrophil subpopulation with plaque vulnerability and the incidence of ACS remains unknown.

Blood samples from 48 patients with unstable angina (UA), 31 with ST-segment elevation myocardial infarction (STEMI) and 33 healthy controls were collected at admission. The morphology of coronary plaques in 48 UA patients were further evaluated by optical coherence tomography (OCT). According to maturation stages of neutrophils and the expression of CD10 and CD101, circulating neutrophils could be divided into pre-neutrophils (CD101^-CD10^-), immature neutrophils (CD101⁺CD10^-) and mature neutrophils (CD101⁺CD10⁺). While the number of pre-neutrophil was quite low in blood and comparable among three groups, the absolute counts and percentage of CD10^- immature neutrophils were higher in peripheral bloods of UA and STEMI patients compared with those in healthy controls. The concentration of plasma myeloperoxidase was positively associated with the percentage of CD10^- immature neutrophils. Furthermore, UA patients with thin-cap fibroatheroma (TCFA) observed by OCT had a higher proportion and larger number of immature neutrophils as compared to those without TCFA. The percentage of immature neutrophils also closely correlated with plaque rupture and the feature of vulnerable plaque, including thinner fibrous cap and larger lipid core, but did not associate with percent lumen stenosis.

Our findings emphasize that the abnormally increased level of CD10^- immature neutrophils may sever as a promising marker of the incidence of ACS and plaque vulnerability.