Screening and identification of epitopes on human immunoglobulin E from 7TMphage display peptide library

    GAO Lin1, YU Chunª²Yan1, SHEN Zhu1, ZHANG Yingª²Qi2, YAN Zhen2

    1Department of Dermatology, Tangdu Hospital, Fourth Military Medical University, Xi¬ðan 710038, China, 2Biotechnology Center, School of Pharmacy, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To identify and characterize epitopes of human immunoglobulin E screened from 7TMphage display peptide library. METHODS: The epitopes of human immunoglobulin E were screened from 7TMphage display peptide library by using antiª²IgE antibody as target protein and were identified by sandwich ELISA. RESULTS: After 3 rounds of screening, 15 of the 48 phage clones were identified as positive clones, which could bind to antiª²human IgE antibody. The amino acid sequences of the positive clones were DHIDMGL, DHMWLGL, DHQDAGF and DHMDQNL. Competitive ELISA results demonstrated the competitive binding of the 4 sequences and IgG to antiª²IgE mAb. Multiple antigenic peptides dot blot displayed that the screened multipeptides could specifically bind to antiª²IgE antibody. CONCLUSION: The screened epitopes are similar in their framwork, and of extensive amino acid homology with IgEª²CH3 region. These phage display peptides can bind specifically to antiª²IgE antibody, providing a basis for further research on IgG related multipeptide vaccine. ......