User:Nicoles1408/sandbox

Plant virus nanotechnology

The art and science of engineering nanomaterials is revolutionizing modern materials and medicine. Viruses are nanoscale objects and these materials have been subject to the nanoscience and nanoengineering disciplines. Viruses can be regarded as prefabricated nanoparticles that have naturally evolved as transporters to deliver cargos to cells and tissues. Building on these properties researchers have turned toward the uses of mammalian viruses as vectors for gene delivery, but also bacteriophages and plant viruses have been used in drug delivery and imaging applications as well as in vaccines and immunotherapy intervention [reviewed in.

With medical applications in mind, there are several attributes to plant viruses that make them an intriguing choice for nanoscience and nanoengineering applications.

-      Plant viruses come in many shapes and sizes: for example, Tobacco mosaic virus (TMV) measures 300x18 nm in size; it forms a hollow rod. Potato virus X (PVX) forms flexible filaments of 515x13 nm. Cowpea mosaic virus (CPMV) has an icosahedral shape measuring 30 nm in diameter. The different shaped-materials have distinct biobehaviors with CPMV interacting with immune cells enabling is use for immunotherapy, while TMV and PVX may be suitable for medical imaging and/or drug delivery applications targeting the diseased vessel wall (cardiovascular disease) or cancerous tumor tissue.

-      These are just some examples, many different plant viruses are being engineered and studied for their potential applications in medicine, some examples include Cowpea chlorotic mottle virus, Red clover necrotic mottle virus, Physalis mosaic virus, Papaya mosaic virus.

-      Plant viruses are not infectious toward mammals. In contrast to mammalian viruses, there is no risk of a viral infection. Furthermore, virus-like particles (VLPs) can be produced that lack the viral genome; these VLPs are non-infectious also toward plants and thus considered safe also from an agricultural point of view.

-      Plant viruses and their non-infectious counterparts can be produced in large yields through molecular farming in plants. The production of pharmaceuticals in plants has advantages, e.g. avoidance of possible animal pathogens and endotoxins. Plant molecular farming is highly scalable and cost efficient.

-      The plant virus-based nanoparticles can be tailored for specific applications using a number of chemical biology approaches: genetic modification can be used to modify the amino acid sequence of the coat protein, i.e. to incorporate epitopes to elicit specific immune responses for vaccines or add peptide sequences to re-direct the particles to desired molecular receptors, e.g. to target sites of inflammation for risk stratification and prognosis of disease. Bioconjugate chemistry can be used to introduce non-biological cargos, such as a contrast agent for imaging or chemotherapy for treatment. Lastly, while often shown as rigid materials, the viruses are dynamic materials that undergo swelling and other conformational changes allowing for cargo to be infused or encapsulated into their viral capsids.

Manifold plant virus platform technologies are being developed and studied for many applications, including:

-      Vaccines: VLPs or epitope display platforms

-      Immunotherapies: in situ vaccines

-      Molecular imaging contrast agents

-      Drug delivery: targeting both human health and plant health

-      Battery electrodes

-      Sensor applications

-      And many others.