Targeted integration of a large transgene cassette by TALEN and ZFN-mediated homologous recombination.

Targeted transgene integration by homologous recombination (HR) represents a promising strategy for gene therapy as it may overcome the issue of insertional mutagenesis associated with retroviral vectors. We recently published the feasibility of using adenoviral vectors (Ad) to package and deliver functional TALEN genes into human cells, demonstrating that Ad-TALEN-mediated transduction results in efficient site-specific DSB formation at the chromosomal safe harbor site AAVS1. Moreover, we demonstrated efficient targeting at AAVS1 in human repopulating epidermal stem cells upon Ad-ZFN cleavage.