CHIMERIC ANTIGEN RECEPTOR T CELLS TARGETING ΑVΒ6 INTEGRIN FOR CHOLANGIOCARCINOMA
Cholangiocarcinoma (CCA) is a fetal bile duct cancer that has poor prognosis and treatment outcome. The development of chimeric antigen receptor (CAR) T-cell is one of potential treatments for CCA. The αvβ6 integrin may serve as target for the development of CAR T-cells against CCA. This study aimed to investigate αvβ6 expression in patients’ tissues and developed αvβ6-specific CAR T-cells against CCA cells.
The expression of αvβ6 was investigated in CCA tissues and cell lines using immunohistochemistry (IHC) and flow cytometry, respectively. The CAR targeting αvβ6 was engineered by using a published A20 peptide (A20) as a tumor-targeting domain fused to CD3ζ with either CD28 costimulatory domain (A2028z) or 4-1BB (A20BBz). T cells expressing αvβ6-targeted CAR were prepared using lentiviral vector transduction.
αvβ6 expression was found in 86% (31/36) of CCA tissues but not at adjacent normal bile duct tissues. The αvβ6 also was expressed at the cell surface of CCA cell lines, KKU055, KKU100, and KKU213, but was not in immortal cholangiocytes, MMNK-1. CARs targeting αvβ6 were constructed in lentiviral-based vector and checked for expression in HEK293T cells.
This preliminary study showed that αvβ6 integrin serves as a potential target for CAR T-cell development for CCA. The αvβ6-specific CAR was constructed and could be expressed in human cells. The efficiency of αvβ6-specific CAR T-cells on CCA cell killing will be investigated.