Screening of peptide specific to cholangiocarcinoma cancer cells using an integrated microfluidic system and phage display technology

Cholangiocarcinoma (CCA) is a cancer of the bile duct with high mortality rate and poor prognosis, owing to the difficulty in the early diagnosis and prognosis. The specific biomarkers or affinity reagents toward CCA cells could be great tools to assist in detection of CCA. However, screening of biomarkers/affinity reagents are generally labor-intensive, time-consuming and requiring large volume of samples and reagents. Therefore, we developed an integrated microfluidic system which could automatically perform selections of biomarkers and affinity reagents using phage display techniques. The experimental results showed that the selection of phage-displayed peptides bound to CCA cells was successfully demonstrated on the integrated microfluidic system using fewer reagents, samples and less time (5.25 h per biopanning round, and continuously performed for only 4 panning rounds). Three oligopeptides were screened, and their specificity and affinity toward CCA cells were characterized. Furthermore, comparing to conventional EpiEnrich beads for cancer cell capture, the screened CCA-specific peptides showed relatively low capture rate over control normal cells. It is envisioned that this microfluidic system may be a powerful tool for screening of biomarkers/affinity reagents in clinical diagnosis and target therapy for CCA.