Title : Getting health allies from agriculture enemies: Plant viruses as smart nanoparticles for vaccine/drug delivery
Plant virus nanoparticles (pVNPs) might represent an ideal delivery tool in terms of biocompatibility and biodegradability. They have evolved to use plants as their reproductive hosts, and to this aim, have developed infection strategies very different from those adopted by their animal counterparts, so that if injected into animals they behave as unreplicative nanobjects. Moreover, they offer a wide range of shape diversity, are easy to be chemically/biologically engineered on both the surface and/or the internal cavity of the capsid, are easy, safe and rapid to be produced at low costs in plants. In this perspective, we are exploring the potential for biomedical applications of two structurally different plant viruses, the filamentous Potato Virus X (PVX) and the icosahedral Tomato Bushy Stunt Virus (TBSV) that we produce inoculating the tobacco-relative Nicotiana benthamiana. In previous studies, we have defined how, by biotechnology interventions, we can produce particles carrying antigens for vaccination purposes, and demonstrated that these particles work excellently in activating different types of immune responses (innate and adaptive, humoral and cell-mediated). Because intrinsic toxicity cannot be taken for granted, we have also verified that PVX and TBSV are neither toxic nor teratogenic. To complete the picture, more recently we observed that, when injected in mice, these structurally robust pVNPs do not induce alterations of tissues architecture, although having different behaviours in terms of persistence in the blood stream and biodistribution, probably as a function of their shape and surface characteristics. Overall, these information sets a solid ground reference for future testing of pVNPs designed to answer to specific health challenges, and there is no reason to suppose these nanoparticles will not progress rapidly contributing to widen the number of devices available to face evolving issues in biomedicine.