Screening and evaluating the mimic peptides as a useful serum biomarker of ankylosing spondylitis using a phage display technique

Abstract

To screen specific serum biomarker for ankylosing spondylitis (AS) using a phage random peptide library. A phage random peptide library of random peptide 12-mers was immunoscreened with purified immunoglobulin (Ig) G from sera of AS patients. Positive clones obtained after three rounds of biopanning were detected with ELISA and sequenced. Reaction of the screened positive clones with sera from AS patients, systemic lupus erythematosus (SLE) patients, rheumatoid arthritis (RA) patients, osteoarthritis (OA) patients and healthy controls was detected using phage ELISA. Correlation among erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and the absorbance value of the positive clone in phage ELISA was examined in AS patients. Seventeen out of twenty randomly selected phage clones exhibited specific reaction with purified sera IgG from AS patients, among them seven coming from the same clone whose inserted peptide sequence was LALPPLAPNHHH (named "AS1"). Phage ELISA results showed that the positive reaction rate of the AS1 clone was 92.0% with AS patients, significantly different (P < 0.01) from those with SLE patients (56.7%), RA patients (50.0%), OA patients (13.3%), and healthy controls (14.0%). Absorbance value of the AS1 clone in phage ELISA was significantly higher than those in the other groups (P < 0.05). In addition, the absorbance value of the AS1 clone showed no statistically significant correlation with ESR and CRP in AS patients, suggesting that AS1 detects AS patients through a unique mechanism other than inflammation. The short peptide AS1 obtained through screening of a phage random peptide library with purified serum IgG from AS patients can specifically react with the sera of AS patients, and thereby may be a candidate of AS-specific serum biomarkers.

Screening Preoperative Peptide Biomarkers for Predicting Postoperative Myocardial Infarction after Coronary Artery Bypass Grafting

“…Phage display technology was originally developed to map epitope-binding sites of antibodies by panning phage peptide libraries on immobilized immunoglobulins [8]–[10]. It involves specific screening and affinity selection of a certain phage displaying peptide that is ligand for particular proteins.…”

“…A major advantage of this technology is the extensive control of selection conditions, which allows preservation of the three-dimensional structure of peptides [14], [15]. Previous studies have used phage display peptide libraries to identify candidate biomarkers for diseases [8], [12]. Wang et al identified a mimic peptide as a potential biomarker of ankylosing spondylitis using a phage display peptide library [8].…”

“…Previous studies have used phage display peptide libraries to identify candidate biomarkers for diseases [8], [12]. Wang et al identified a mimic peptide as a potential biomarker of ankylosing spondylitis using a phage display peptide library [8]. Weng et al reported identification of a candidate biomarker for knee osteoarthritis by phage display [12].…”

“…Billions of pooled peptides presented on phage particles form a phage display peptide library [7]. This technology was originally developed to map epitope-binding sites of antibodies by panning phage peptide libraries on immobilized immunoglobulins [8]. Since then, phage display has been widely used to screen targeting peptides in drug discovery and biomarker selection [8]–[10].…”

“…This technology was originally developed to map epitope-binding sites of antibodies by panning phage peptide libraries on immobilized immunoglobulins [8]. Since then, phage display has been widely used to screen targeting peptides in drug discovery and biomarker selection [8]–[10]. In the present study, we used a phage display peptide library to screen potential preoperative peptide biomarkers for predicting PMI after coronary artery bypass grafting (CABG) surgery.…”