Patent ID: 7250299
Filing Date: 2007-07-31
Classification: C12N

Abstract:
1. A lentiviral vector system comprising a lentiviral packaging system and a lentiviral transfer vector comprising a heterologous gene operably linked to a regulatory element, wherein the lentiviral packaging system comprises a structural lentiviral vector system comprising a first lentiviral vector that encodes a structural gene selected from a gag gene, a pol gene or both gag and pol genes; and a regulatory lentiviral vector comprising a rev gene, wherein the regulatory lentiviral vector is provided on a separate construct from the structural lentiviral vector system, wherein the lentiviral transfer vector comprises a 5′ LTR and a 3′ LTR, wherein the regulatory element is a heterologous regulatory element operable in a mammalian cell, wherein a part or all of a regulatory element of the U3 region of the 5′ LTR is replaced by the heterologous regulatory element, wherein a part or all of the U3 region of the 3′ LTR is replaced by a heterologous inducible regulatory element that is activated only in the presence of an activator expressed in trans, and wherein the lentiviral vector system lacks a functional tat gene.