Patent ID: 6872528

Claim:
A packaging cell line for the production of defective infectious retroviruses, wherein said packaging cell line is a human cell comprising, in its genome, at least two retroviral vectors: (a) wherein the first retroviral vector comprises, under the control of a LTR (Long Terminal Repeat) type promoter, the sequence of retroviral gag/pol genes, a mutated or normal IRES (Internal Ribosome Entry Sites) sequence, the sequence of a first selection gene, and a polyadenylation sequence; (b) wherein the second retroviral vector comprises, under the control of a promoter, the sequence of a gene coding for an envelope protein, a mutated or normal IRES sequence, the sequence of a second selection gene and a polyadenylation sequence; and (c) said first and second vectors being free of a retroviral packaging sequence.