Identification of the Peptides that Bind to PTA1 mAb(LeoA1) by Phage Displayed Library / 细胞与分子免疫学杂志

ABSTRACT

Aim To screen peptides binding specifically to anti-human PTA1mAbs from a random twelve-peptide phage-disp-layed library. Methods Series of PTA1mAbs(LeoA1、 1B11、 C9、 2D1、 2E9、 2G8、 2H2 and E8)were purified using protein-A affinity column. PTA1mAbs which could bind PTA1-Fc fusion protein binding to its ligand were confirmed by flow cytometry, and then used as target to screen phage library. After three rounds of affinity screening, the peptide sequences of positive phage clones were determined and analyzed. Results LeoA1 could block PTA1-Fc fusion protein binding to its ligand. 13 phages which could bind specifically to LeoA1 were isolated from phage library and further confirmed by ELISA. Conserved motifs were found among the sequences of the peptides. Conclusion It was shown that the conserved motifs were candidafe regions binding to PTA1 ligand,which is important to identify functional epitopes for seeking ligand of PTA1 and further investigation of biological function of PTA1.