Table 1.

Frequencies of gene transfer and recombinations between helper virus and gene vectors

Type of experiment		Gene transfer, no. of positive wells/wells plated	Recombination frequency (accidental GFP transfer), no. of positive wells/wells plated
Cells infected	Supernatant with packaged plasmid
Raji	p2124	288/288 (100%)*†	ND
Raji	p2194	72/96 (75%)†‡	ND
Raji	p588	96/96 (100%)*	32/96 (33%)
Raji	p1495	192/192 (100%)*	5/192 (2.6%)
Primary B cells	p1495	96/96 (100%)§	0/96 (0%)

ND, not done. 

^*Proliferation of Raji cells under selection with 200 μg/ml of hygromycin. 

^†GFP-positive Raji cells. 

^‡Proliferation of Raji cells under selection with 3 ng/ml of colchicine. 

^§Proliferation of immortalized B cell clones.