Perilipin 2 levels are increased in patients with in-stent neoatherosclerosis: A clue to mechanisms of accelerated plaque formation after drug-eluting stent implantation

Background: Perilipin 2 (PLIN2) is a protein that potentially facilitates atherogenesis in native coronary arteries or arteries with an implanted drug-eluting stent (DES). The aim of the study was to determine PLIN2 protein levels in peripheral monocytes of enrolled subjects and compare them between patients with native coronary artery disease (CAD) and those with an in-stent restenosis (ISR) due to neoatherosclerosis occurring >1 year after DES implantation. Methods: Forty-two patients were prospectively enrolled in the study in 3:1 fashion and underwent coronary catheterization. Both groups were angiographically matched for CAD burden with respect to the number of diseased vessels. Neoatherosclerosis was determined by intracoronary optical coherence tomography (OCT) among patients with ISR. Results: Patients with ISR due to neoatherosclerosis had significantly higher PLIN2 protein levels in peripheral blood monocytes compared to patients with native CAD (342.47 ± 75.63[SE] versus 119.51 ± 20.95, p < 0.001). PLIN2 protein levels did not significantly differ between unstable and stable disease phenotype (125.59 ± 131.02 vs. 146.14 ± 111.87, p = 0.109). Conclusions: In this explorative study, PLIN2 protein levels are significantly increased in patients with neoatherosclerosis, irrespective of clinical presentation, implicating that it might play a pathogenetic role in accelerated atherosclerosis after DES implantation. Further larger clinical studies are warranted to confirm these initial findings.