ABSTRACT
Provided herein are methods for generating reversion free attenuated and/or replication incompetent vaccine vectors and their use in vaccine compositions and vaccination. In particular, the use of a codon shuffled helper gene is used to produce compositions comprising replication incompetent virus.
CLAIMS
1. A method of preventing or reducing viral reversion of a virus during culture, the method comprising: a) stably expressing a codon shuffled helper gene in a host cell, wherein the helper gene is codon modified to reduce expression of the helper gene in the host cell relative to the expression of an unmodified helper gene; and b) culturing the host cell under conditions conducive to the propagation of a replication incompetent virus, wherein the helper gene is deleted from the virus thereby rendering the virus replication incompetent.