Objective: To select the binding-peptide of the cell surface marker CD133 of cancer stem cells from phage peptide library, and to find a new tool for research on stem cells, tumor therapy and anti-metastasis of cancer.
Methods: Biotined mouse CD133 extracellular fraction was used as a target to screen phage 7-peptide library by the high affinity of streptavidin and biotin, and the clones were identified by sandwich ELISA and competitive experiment. Single strand DNA was extracted from these positive clones and was analyzed by single-strand dideoxy-sequencing.
Results: After three turn solution panning, five peptides with high affinity shared the same amino acid sequence: APSPMIW and three identical peptides with high affinity shared the same amino acid sequence: LQNAPRS.
Conclusion: The peptides that bind with mouse CD133 extracellular fraction with high affinity and specificity were first screened from the phage peptide library for the first time, which initially indicates that the feasibility of screening from phage peptide library with small molecule polypeptide biotined as a target.