OBJECTIVETo investigate the specific cytotoxity of tumor infiltrating lymphocytes (TIL) transfected with chimeric T cell receptor (CTCR) on cells which express KDR.

METHODSA recombinant retroviral plasmid (pMSCVneo-Vhgamma) was constructed by cloning VEGF121-hinger-FcRgamma (Vhgamma) into retroviral vector pMSCVneo. After packaging by PT67, the virus with high titer was used to infect TIL isolated from liver cancer tissues, and then MSCVneo-Vhgamma-TIL was generated. TIL infected with MSCVneo was used as a control. The cytotoxicty of the transgenic TIL on NIH3T3 and HepG2 expressing no KDR and on ECV304 and A375 expressing KDR was detected with MTT colorimetric assay.

RESULTSThe sequences of VEGF121 and hinger-FcRgamma were different from those reported, but the deduced amino sequences were identical to the reported ones. The cytotoxity of TIL infected with MSCVneo on target cell was similar to that of the control TIL; both only had mild cytotoxity on cancer cell line. No significant cytotoxity was found in TIL infected with MSCVneo-cTCR on NIH3T3, but its cytotoxity on ECV304 was significant. The cytotoxity on HepG2 was similar to that of MSCVneo-TIL and uninfected TIL, but cytotoxity on A375 was significantly higher.

CONCLUSIONChimeric T cell receptor permanently grafts TIL cell with predefined new specificity. TIL expressing Vhgamma can selectively recognize and kill vascular endothelial cell and tumor cells which express VEGF receptor KDR.