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Establishment of hepatocarcinoma cell line transfected by the B7 gene and its biocharacteristics.

OBJECTIVE
To study the function of costimulation sign in tumor immunology and construct the new cell line B7+ Smmc7721.


METHODS
The B7 gene was transfected into the hepatocarcinoma cell Smmc7721 by liposma. Polymerase chain reaction (PCR) and reverse transcriptase-PCR (RT-PCR) were applied to test the result. MTT colorimetric assay was used to value the killing effect of lymphokine activated killer cells (LAK) activated by IL-2 on the transfected cell line and the original line.


RESULT
B7+ Smmc7721 was improved to be steadily expressed B7 molecule and LAK cells could more effectively act on the B7+ Smmc7721 cells.


CONCLUSION
The B7 gene can be transfected to hepatocarcinoma cells and can be expressed steadily in vitro, thus increasing the efficiency of LAK cells activated by IL-2 on them.