[Association between CD137 and ischemia-reperfusion injury in patients with acute ST-segment elevation myocardial infarction].

Objective: To explore the relationship between the levels of serum soluble CD137 (sCD137) and membrane-bound CD137 (mCD137) and the occurrence of ischemia reperfusion injury (IRI) in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: This is a cross-sectional study. Consecutive patients with acute STEMI, who underwent emergency percutaneous coronary intervention (PCI) in the Department of Cardiology, Jiangsu University Affiliated Hospital from May 2019 to September 2020, were enrolled. According to the absence or presence of IRI, patients were divided into IRI group and non-IRI group. Clinical data of the two groups were collected and compared. sCD137 level was detected by enzyme linked immunosorbent assay. Ficoll density gradient centrifugation was used to separate peripheral blood mononuclear cells (PBMC) and RNA was extracted, mCD137 mRNA expression level was detected by PCR. Serum sCD137 levels and the mCD137 mRNA levels of PBMC before, after PCI and 24 hours after PCI were compared. The correlation between serum sCD137 level, PBMC mCD137 mRNA level and clinical indicators was observed. The univariate and multivariate logistic binary regression analyses were performed to evaluate the related risk factors of IRI. ROC curve was used to analyze the predictive value of defined parameters for IRI. Results: A total of 112 STEMI patients were enrolled. There were 42 cases (of which 33 were males (78.6%), mean age was (58.6±12.7) years) in non-IRI group and 70 cases(of which 56 were males (80.0%), mean age was (64.5±11.6) years) in IRI group. Compared with the non-IRI group, patients in the IRI group had longer hospital stays, older age, lower rates of obesity, lower systolic and diastolic blood pressure at admission, higher proportion of the the right coronary artery as culprit vessel, lower rate of the use of angiotensin-converting enzyme inhibitor/angiotensin-Ⅱ receptor blocker/angiotensin receptor neprilysin inhibitor, higher levels of urea nitrogen and creatinine, lower glomerular filtration rate, lower triglycerides, higher D-dimer and B-type natriuretic peptide _max , higher proportion of Killip grade Ⅳ and cardiovascular adverse events (all P <0.05). sCD137 levels at the preoperative, postoperative and 24 hours after surgery were significantly higher in the IRI group than in the non-IRI group, while the mRNA levels of CD137 was similar between the two groups. The level of sCD137 in patients after PCI was lower than that before operation, the level of mCD137 mRNA was higher than that before operation ( P <0.05). Serum sCD137 levels were positively correlated with hospitalization days, age, B-type natriuretic peptide, creatinine, ischemic time, C Reactive protein (CRP) and CRP/albumin ( P <0.05), and negatively correlated with body mass index, glomerular filtration rate and albumin ( P <0.05). The mCD137 mRNA expression level of PBMC was positively correlated with hospital stay, age, B-type natriuretic peptide, ischemic time, CRP and CRP/albumin ( P <0.05), and negatively correlated with body mass index, glomerular filtration rate, albumin ( P <0.05). Multivariate logistic regression analysis showed that higher sCD137 ( OR =1.038, 95% CI : 1.009-1.069), aspartate aminotransferase, ( OR =1.029, 95% CI : 1.009-1.050) and lower albumin ( OR =0.829, 95% CI : 0.703-0.829) before surgery were independent risk factors of IRI ( P <0.05). Receiver operating characteristic curve showed that the area under the curve of sCD137 was 0.672 (95% CI : 0.574-0.770, P =0.002) for the prediction of IRI, the best cut-off value was 28.43×10 ^-3 μg/L with sensitivity of 95.2% and specificity of 48.6%. Conclusion: The significantly increased level of sCD137 in acute STEMI patients is positively correlated with reperfusion injury, which is an independent risk factor of IRI and may be related to the prognosis of patients with IRI.