Structure-based design and experimental engineering of a plant virus nanoparticle for the presentation of immunogenic epitopes and as a drug carrier

Abstract

Biomaterials research for the discovery of new generation nanoparticles is one of the most active areas of nanotechnology. In the search of nature-made nanometer-sized objects, plant virus particles appear as symmetrically defined entities that can be formed by protein self-assembly. In particular, in the field of plant virology, there is plenty of literature available describing the exploitation of plant viral cages to produce safe vaccine vehicles and nanoparticles for drug delivery. In this context, we have investigated on the use of the artichoke mottled crinkle virus (AMCV) capsid both as a carrier of immunogenic epitopes and for the delivery of anticancer molecules. A dual approach that combines both in silico tools and experimental virology was applied for the rational design of immunologically active chimeric virus-like particles (VLPs) carrying immunogenic peptides. The atomic structures of wild type (wt) and chimeric VLPs were obtained by homology modeling. The effects of insertion of the HIV-1 2F5 neutralizing epitope on the structural stability of chimeric VLPs were predicted and assessed by detailed inspection of the nanoparticle intersubunit interactions at atomic level. Wt and chimeric VLPs, exposing on their surface the 2F5 epitope, were successfully produced in plants. In addition, we demonstrated that AMCV capsids could also function as drug delivery vehicles able to load the chemotherapeutic drug doxorubicin. To our knowledge, this is the first systematic predictive and empirical research addressing the question of how this icosahedral virus can be used for the production of both VLPs and viral nanoparticles for biomedical applications.

Display of whole proteins on inner and outer surfaces of grapevine fanleaf virus‐like particles

“…First, their external surfaces can be modified or decorated with other molecules, in which case VNPs can act as biocompatible nanocarriers for antigen presentation, immunomodulation, customized targeting, etc., as exemplified by the plant-infecting cowpea mosaic virus (CPMV, Chatterji et al, 2004;Lewis et al, 2006;Sainsbury et al, 2010;Steinmetz et al, 2011), tobacco mosaic virus (TMV, Alonso et al, 2013) or cowpea chlorotic mottle virus (CCMV, Suci et al, 2007). Second, as self-assembled cages, the inner cavity of VNPs can be used to encapsulate or encage a variety of active molecules, including pharmaceuticals, image enhancers and nucleic acids (Arcangeli et al, 2014;Bruckman et al, 2013;Mueller et al, 2011;Shriver et al, 2013). By acting on both external surface and inner cavity, VNPs can be adapted theoretically at will and are therefore regarded as extremely versatile tools with great potentials in medicine, as enzyme nanocarriers or even as novel biomaterials (for review, see Reference Alonso et al, 2013;Cardinale et al, 2012;Pokorski and Steinmetz, 2010).…”

The Generation of Turnip Crinkle Virus-Like Particles in Plants by the Transient Expression of Wild-Type and Modified Forms of Its Coat Protein

“…Previous work on the structurally related Tombusvirus, Tomato bushy stunt virus (TBSV), showed that peptides could be fused to the C-terminus of the coat protein so that they are expressed on the P domain without abolishing virus or VLP assembly (Joelson et al, 1997 ; Kumar et al, 2009 ). The neutralizing HIV-1 2F5 epitope was recently expressed on Artichoke mottled crinkle virus surface, a virus also of the Tombusvirus genus (Arcangeli et al, 2014 ). We therefore decided to investigate whether it would be possible to present whole proteins, as opposed to peptides, on the surface of plant-expressed TCV VLPs.…”

How Computational Epitope Mapping Identifies the Interactions between Nanoparticles Derived from Papaya Mosaic Virus Capsid Proteins and Immune System

“…Papaya mosaic virus nanoparticles that have been fused or conjugated with antigenic peptides have triggered immunogenic responses in mammals [5,10,24,25]. Over the past decade, various virus nanoparticles have been generated against different diseases [6].…”

“…It is important to note that achieving an efficient virus nanoparticle for vaccine production requires a safe expression system in which large quantities of the desired protein can be easily produced [6]. Even though physiochemical and structural properties of virus nanoparticles highly affect their efficacy, the significance of a well-designed platform should never be neglected [25]. We, therefore, examined the immunogenicity Fig.…”