Generation of recombinant protein shells of Johnson grass chlorotic stripe mosaic virus in tobacco plants and their use as drug carrier

Abstract

The development and use of virus-like particles (VLPs) is a growing field with a powerful potential in generation of nanoparticles. In the present study we have attempted to generate and use empty shells of Johnson grass chlorotic stripe mosaic virus (JgCSMV, a member of the genus Aureusvirus, family Tombusviridae) as VLP nanoparticles for drug loading. In order to successfully produce recombinant JgCSMV-derived VLPs, we followed an approach based on cloning of the JgCSMV CP gene into pBI121 vector and introduction of the latter into Agrobacterium rhizogenes and transformation of tobacco cells for coat protein expression. Expression in tobacco tissue was demonstrated in transformed hairy roots as a model system. Recombinant VLPs were purified, analyzed by immune assay and visulalized by electron microscopy. Next, we explored the possibility of using JgCSMV-derived VLPs as a nanocontainer for loading the anticancer drug doxorubicin (DOX), taking advantage of the reversible swelling of VLPs in vitro. The results showed that transformed hairy roots produced high levels of the recombinant protein that readily assembled to form empty shells with overall structure similar to native virus particles. In addition, we demonstrated that JgCSMV-VLPs could function as vehicles able to load the chemotherapeutic drug doxorubicin. To our knowledge, this is the first research addressing the question of how this icosahedral virus (JgCSMV) can be used for the production of nanocontainers for biomedical applications.