Patent ID: 6350575
Filing Date: 2002-02-26
Classification: C12N

Abstract:
A process for preparing an adenoviral particle comprising a recombinant adenoviral vector, which comprises:(i) preparing a recombinant adenoviral vector deficient for replication; (ii) preparing a helper vector which complements in trans said recombinant adenoviral vector deficient for replication and which comprises a first recombination sequence 5â€² and a second recombination sequence 3â€² of a region essential to the propagation of said helper vector, wherein said recombination sequences are recognized by a recombinase; (iii) introducing the recombinant adenovirail vector and the helper vector into a permissive or an appropriate cell line wherein said cell line does not constitutively produce active recombinase; (iv) culturing said introduced cell line under appropriate conditions to increase the quantities of said helper vector and of said recombinant adenoviral vector; (v) culturing said introduced cell line under appropriate conditions to allow the production of the viral particle in the presence of an active recombinase able to recognize said first and second recombination sequences; and (vi) recovering the adenoviral particle in the cell culture; wherein said helper vector, said recombinant adenoviral vector, or said cell line comprises a DNA fragment coding for a recombinase and elements for its expression; and wherein said elements confer an inducible expression in response to an inducer, or said recombinase is expressed in an inactive form and is activated in the presence of a ligand, or both.