Anti-tumor Necrosis Factor-alpha Monoclonal Antibody On The Phage Random 12 Peptide Library Immunization Screening

Aim To obtain the short peptides from a random bacteriophage 12 mer peptide library through screening the epitope of monoclonal antibody against tumor necrosis factor(TNF-a). And use the epitope to study SLE.Methods Anti-TNF-a was used to immunoscreen a phage random peptide library of 12 amino-acidresidues displayed as a fusion to protein III of filamentous phage M!3 .The positive clones were obtained by three rounds of biopanning, absorb-wipe out-extend. With the reduceing of monoclonal antibody's consistency, the reactivity of positive clones were inceased. After 3 rounds biopanning, single peptides were randomly selected, and extended. The reactivity of each clone binding to anti-TNF-a was examined by double-antibody sandwich ELISA and Dot-ELISA. Mixed positive phage clones, which had the most reactivity, were used to detect SLE patients' sera and healthy persons' by Dot-ELISA.Results The eluted phages were enriched nearly lOOfold through three rounds of biopanning, 7 phage clones from the third round biopanning were randomly selected and 5 clones of them could bind to the anti-TNF-a. The binding rate of mixed clones with SLE patients was significantly higher than that of healthy persons.Conclusion The phage display technique can be applied to study the anti-TNF-a antigenic peptides, and these epitopes provide the potential for developing study of SLE.