In most gene therapy studies, a “normal” gene is inserted into the genome to replace an “abnormal” disease-causing gene. A carrier molecule called a vector must be used to deliver the therapeutic gene to the patient’s target cells. Currently, the most common vector is a virus that has been genetically altered to carry normal human DNA. Viruses have evolved a way of encapsulating and delivering their genes to human cells in a pathogenic manner. Scientists have tried to take advantage of this capability and manipulate the virus genome to remove disease-causing genes and insert therapeutic genes.
Due to the very efficient nuclear entry mechanism of adenovirus and its low pathogenicity for humans, adenovirus-based vectors have become gene delivery vehicles that we are using to infect primary cell culture of neurons, for example. The adenoviral vectors system (AdEASY), used in our lab, allows the production of recombinant adenoviruses with high titers, including a reporter gene for monitoring the infection efficacy.
Lentiviral vectors provide attractive gene delivery vehicles in the context of non-dividing cells. The vectors also have proved to be highly efficient for in vivo gene delivery and achieve stable long-term expression of transgene in serveral target tissues, such as the brain.
A third-generation lentivirus vector was designed to improve their biosafety.
AdV infected dorsal root ganglia neurons expressing eGFP.