Adenovirus: weapons of mass transduction for gene delivery

Adenovirus (AV) are non-enveloped and non-integrative icosaedral viruses. Recombinant AV (genetically modified with respect to the wild-type in order to lose their capacity of replication) are widely used for their high infectivity (almost 100% in almost all mammalian cell types) their high level of expression of exogenous protein (up to 20% of total host protein expression), their episomal maintenance (non-integrative, non-genome disruptive ) and because they are easy-to-use in vitro and in vivo. Among their advantages, their ability for delivering large inserts (up to 8 kb) and their strong safety track records are paramount. They are also able to infect dividing and non-dividing cells, primary stem or somatic cells even at the latest stages of differentiation. The main issue of AV is that being episomal and non-replicative, they do not expand with cell proliferation, thus making them optimal for short term expression applications (up to 2-3 weeks depending on the targeted cell) and never suitable for long term studies. Also, AV capsides are immunogenic, which is redhibitory for iterative long-term applications. If immunogenicity must be ruled out, the best alternative to AV should be adeno-associated viruses (only for shorter inserts up to 5 kb) or lentiviral particles (for longer inserts up to 8 kb) both with their potentially harmful ability for genomic integration. As AV can deliver large inserts, both single¹ and dual² cistronic expression vectors are commercially available as shown in the table below: 1 – delivery of a unique gene 2 – delivery of a gene of interest under one promoter along with expression of a reporter gene under another promoter If you are interested in purified, ready-to-use AV particles or if you have any questions about this topic, I’ll be pleased to help you out. Just leave your comments below!