Chemiluminescence resonance energy transfer-based method to investigate the platelet surface molecule in acute myocardial infarction.

The chemiluminescence resonance energy transfer (CRET)-based method was applied to the detect of CD61 and CD62P (P-selectin) on the surface of platelet in patients with acute myocardial infarction (AMI) and healthy controls. Patients admitted to the Department of Emergency in The First Affiliated Hospital of Soochow University from May 2025 to December 2025 were recruited. We studied 22 AMI patients who were matched with 22 controls. The coefficient of variations and standard curves of indexes were calculated. Expressions of CD61 and CD62P in plasma were evaluated by CRET assay. Standard curve property for CD61 and CD62P: R2 .995 and 0.9999. The coefficient of variation in CRET system was 3.39%, 1.76% (QC high), 6.25% and 7.16% (QC low) for CD61 and CD62P, respectively. CRET data showed the agonist (arachidonic acid and ADP) concentration dependency on platelet activation. AMI patients had higher basal CD62P levels when compared to controls. The platelet aggregation rate of AMI patients had a strong positive correlation with the expression of CD62P (r = 0.8354, p < .0001). In the healthy controls, the platelet CD61 and CD62P expression detected by flow cytometry showed a positive correlation with that evaluated by CRET (r = 0.4296, p = .0460; r = 0.5662, p = .0060, respectively). After platelet activation with AA or ADP, the expression levels of CD62P detected by flow cytometry were positively correlated with those measured by the CRET method (r = 0.6195, p = .0021; r = 0.7663, p < .0001, respectively). Expressions of CD62P elevated after agonist stimulation in AMI patients and controls in vitro. With the biomarker of CD62P as the model, the Area Under Curve (AUC) was 0.9236 (p < .0001). The cutoff value of CD62P to evaluate platelet reactivity by CRET was 3.985%. This one-step CERT assay provided a new approach to detect platelet activity of acute myocardial infarction.