Screening and Characterization of the Mimotopes of Adveanced Oxidation Protein Products from Phage Peptide Library

Objective To screen and characterize the antigenic mimotopes of advanced oxidation protein products(AOPP) from a random 12-mer phage display peptide library,and to explore the expression or distribution of the mimotope sequences to AOPP.Methods The polyclonal antibodies(PcAbs)against AOPP was used as targets to screen the 12-mer phage display peptide library,and the specificity of phage clones were identified by sandwich ELISA and competitive ELISA.The peptide sequences displayed on positive phage clones were determined by DNA sequencing,and analyzed by bioinformatics.Results Eighteen of phage clones displaying mimotopes of AOPP were isolated in positive rate of 62.07%,which showed a specific reactivity with the PcAbs.The reactivity of PcAbs with positive phage clone No.6 could be well inhibited by AOPP with 0.2μg/ml for IC50,indicating that phage No.6 mimics antigenicity of AOPP epitope.The analysis on amino acid sequence revealed that mimotope sequences contained a common motif LXDMLXD,X is random amino acid.The analysis by bioinformatics showed that the conservative sequences are presented in some fungus and proteins of some parasites.Conclusion The mimotopes of AOPP were obtained by using the phage display technology,which are not presented in protein molecules of normal human and mammalian.