| 摘要 |
An animal cell is co-transfected with both a recombinant DNA viral vector which bears a promoter, a recombinase gene and a poly(A) sequence and a recombinant DNA viral vector which bears two recombinase-recognition sequences and which further bears an origin of replication, a promoter a foreign gene and a poly(A) sequence, each of which is located between the two recombinase-recognition sequences. Thereafter, in the co-transfected animal cell, a DNA fragment containing the origin of replication, promoter, foreign gene and poly(A) sequence is excised from a vector by the action of recombinase expressed by the other vector. The excised DNA fragment forms a circular DNA molecule which autonomously replicates in the co-transfected animal cell due to the origin of replication, whereby the foreign gene is continuously expressed. Accordingly, when the foreign gene corresponds to a gene which is defective in a patient, the combination of the above two DNA viral vectors is useful in gene therapy, especially in the treatment of a patient with a hereditary disease. |
