VLPs Derived from the CCMV Plant Virus Can Directly Transfect and Deliver Heterologous Genes for Translation into Mammalian Cells

Abstract

Virus-like particles (VLPs) are being used for therapeutic developments such as vaccines and drug nanocarriers. Among these, plant virus capsids are gaining interest for the formation of VLPs because they can be safely handled and are noncytotoxic. A paradigm in virology, however, is that plant viruses cannot transfect and deliver directly their genetic material or other cargos into mammalian cells. In this work, we prepared VLPs with the CCMV capsid and the mRNA-EGFP as a cargo and reporter gene. We show, for the first time, that these plant virus-based VLPs are capable of directly transfecting different eukaryotic cell lines, without the aid of any transfecting adjuvant, and delivering their nucleic acid for translation as observed by the presence of fluorescent protein. Our results show that the CCMV capsid is a good noncytotoxic container for genome delivery into mammalian cells.

Brome mosaic virus-like particles as siRNA nanocarriers for biomedical purposes

“…Both BMV and CCMV viruses have hydrophobic residues in their capsid protein in which hydrophobic molecules, such as NanoOrange, are bound. Due to the high fluorescence of this fluorophore, the internalization into tumor cells using this labeling technique appears to be better when compared with some previous reports [31][32][33]. The NanoOrange-loaded BMV and CCMV capsids were then incubated in MCF-7 cell cultures for 4 h to evaluate their internalization into the breast cancer cells.…”

In Vitro Assembly of Virus-Like Particles and Their Applications

“…Bacteriophage MS2 VLPs produced in E. coli were disassembled at low pH, while human papillomavirus (HPV) VLPs obtained from insect cells were dissociated with carbonate buffer at pH 9.6 [29,30]. Cowpea chlorotic mottle virus (CCMV) particles assembled in plants were denatured in a neutral buffer with high salt concentration [31][32][33]. Urea is commonly used to disassemble the formed VLPs.…”

“…Cells are harvested by filtration, frozen and then VLPs are released by homogenization. For some L1 types (31,33,45,52,58), a protease inhibitor is added. Purification comprises cross-flow membrane filtration for debris removal, cation exchange chromatography for host cell protein removal, and hydoxyapatite chromatography for polishing and enrichment of monodisperse VLPs.…”

“…CCMV VLPs were produced in plant cells, the particles were then disassembled in a high-salt concentration buffer at neutral pH. Reassembly and packaging followed by adding cargoes and dialyzing into an acidic buffer (at pH 4.5-4.8) [31][32][33], which can be used to package RNA replicons [156], or a neutral buffer which has been used with DNA cargoes [54]. CCMV VLPs were also produced using E. coli by expressing soluble capsid proteins, followed by purification and assembly in the presence of cargoes.…”

The Adoption of Viral Capsid-Derived Virus-Like Particles (VLPs) for Disease Prevention and Treatments

“…VLPs contain repetitive, high-density displays of viral surface proteins that present conformational viral epitopes that can elicit strong T cell and B cell immune responses [ 2 ]. Moreover, VLPs would be adopted for delivery of genes and other therapeutic agents [ 3 ]. As indicated by Mohosen et al [ 1 ], size and surface geometry are the two main factors driving the interaction between VLPs and the humoral immune system.…”