The clinical implications of increased coexpression of pregnancy associated plasma protein-A and OX40 ligand in patients with acute coronary syndromes

Objective:To investigate whether PAPP-A level was related to serum OX40 ligand (OX40L) level or membrane-bound OX40L level in patients with ACS.Method:All patients underwent coronary angiography in our study.Overall,30 normal controls,60 patients with stable angina (SA) and 80 patients with acute coronary syndromes (ACS),including unstable angina (UA) (n=50) and acute myocardial infarction (AMI) (n=30) were enrolled in current study.Serum PAPP-A and soluble OX40L (sOX40L) were measured by ELISA whereas the expression of OX40L on monocytes were analyzed with flow cytometry.Result:The expression of OX40L in peripheral monocytes in patients with UA [25.6±5.5 mean fluorescence intensity (MFI)] and AMI (29.4±6.3 MFI) were significantly higher than those in patients with SA (10.6±2.8 MFI) and controls (11.1±3.5 MFI) (P0.001).Both sOX40L and PAPP-A in patients with UA (15.7± 4.9 μg/L,25.4±6.8 mg/L,respectively) and AMI (17.1±5.3 μg/L,26.3±5.6 mg/L,respectively) were significantly higher than those in patients with SA (3.4±1.4 μg/L,9.6±2.1 mg/L,respectively) and controls (3.9 ± 1.3 μg/L,8.5±2.8 mg/L,respectively) (P0.001).It was interesting that a positive correlation was found between sOX40L,membrane-bound OX40L and serum PAPP-A levels (r1=0.54,r2=51;P0.0001).PAPP-A levels,serum and membrane-bound OX40L were all significantly correlated with complex coronary stenosis(r1=0.40,r2=0.56,r3=0.55,P0.001).Conclusion:PAPP-A level was related to OX40L in serum and membrane-bound in patients with ACS.Enhanced level of serum PAPP-A and sOX40L may represent markers for coronary disease activity.