October 25, 2023 11:15 am
October 25, 2023 12:05 pm
Distinguished Professor of Chemistry
University of California - Los Angeles
Viruses have evolved to do essentially one thing – namely, protect their genes until they can deliver them to the right cell. Accordingly, any gene delivery program should follow the lead of viruses in striving for this level of protection and targeting. In contrast to the lipid nanoparticles and engineered viruses that are currently the prevailing gene vectors, we synthesize stoichiometrically-precise virus-like particles (VLPs) from in vitro transcribed mRNA and purified viral capsid protein. The recombinantly-expressed protein comes from one of two plant viruses, and – upon interacting with RNA – forms either a perfectly monodisperse spherical or cylindrical VLP with a single RNA molecule inside. The mRNA encoding the therapeutic gene of interest is rendered self-amplifying by fusing it to an RNA replicase gene, and the corresponding VLPs, upon conjugation with targeting antibodies, are shown to result in strong downstream protein expression when transfected into cell culture or injected into mice. I discuss applications of this platform to vaccines and to cancer immunotherapy.