What are the challenges of using viral vectors for therapeutic applications?
Additionally, while wild-type viruses are rather selective in which cells they infect, recombinant viral vectors can have greatly expanded transduction ranges. This is a double-edged sword, as increased transduction can elevate gene transfer efficiency, but non-specific transduction can decrease the titer available at the intended site and elicit side-effects such as immune activation.1
Finally, some viral vectors integrate their genomes into existing cellular genomes, creating a risk of oncogenesis if these gene insertions disrupt existing cancer-linked genes. The incorporation of “suicide genes” – genes designed to terminate cancer cells – and developing targeted gene insertion strategies are potential methods to alleviate this risk.1
1. C.E. Thomas, et al., “Progress and problems with the use of viral vectors for gene therapy,” Nat Rev Genet 4(5): 346-358, 2003.