| 摘要 |
PROBLEM TO BE SOLVED: To enhance the expression of a tissue plasminogen activator (TPA), useful as a thrombolytic agent, by introducing a specific DNA into ovarian cells of Chinese hamster and culturing them. SOLUTION: A DNA coding TPA, a different non-viral protein, and an auxiliary DNA (adenovirus DNA coding VA RNA) are introduced into ovarian cells of Chinese hamster (CHO) to obtain transformed CHO cells producing recombinant TPA and the cells are cultured in a serum-free culture medium substantially containing no plasminogen whereby TPA can be produced at a rate of at least 0.6mU/cell/day. |
