Association of Serum Anti-Prolylcarboxypeptidase Antibody Marker with Atherosclerotic Diseases Accompanied by Hypertension

Abstract

Background: Atherosclerosis is leading to mortal diseases such as Cerebral Infarction (CI), and Cardiovascular Disease (CVD), and closely related to Diabetes Mellitus (DM) and Chronic Kidney Disease (CKD). Biomarkers are useful but not sufficient for early detection. In the present study, we aimed to identify novel antibody markers for atherosclerosis-related diseases. Methods: The protein array method was used for the initial screening, and a peptide containing a possible epitope domain was used to evaluate serum antibody levels using the Amplified Luminescent Proximity Homogeneous Assay (AlphaLISA) method. Results: The protein array identified prolylcarboxypeptidase (PRCP) as one of the target antigens recognized by IgG antibodies in the sera of patients with atherosclerosis. We then prepared a possible antigenic peptide of amino acids 214-227 of PRCP. Results of AlphaLISA showed significantly higher serum antibody levels against the PRCP peptide in patients with DM, CVD, acute-phase cerebral infarction, transient ischemic attack or CKD, than in healthy donors. Furthermore, areas under the receiver operating characteristic curves of these antibodies were higher in patients with DM or CKD than in other patients. Spearman correlation analysis revealed that the serum anti-PRCP antibody levels were associated with hypertension, artery stenosis, and smoking habit.. Conclusion: The serum anti-PRCP antibody may be useful for early detection of atherosclerosis-related diseases, and may have a pathogenic role in the development of atherosclerosis.