Application of plant viruses as nano drug delivery systems.

Nano-sized drug delivery systems based on virus-derived platforms have promising delivery and targeting efficiencies. To date, much of our understanding of these systems is obtained from studies of animal viruses. Application of plant viruses for drug delivery is in the nascent stage, but it is becoming apparent that plant viral particles can be engineered to possess novel properties to meet the unique requirements of targeted drug delivery. Chemical functionalization of a plant viral particle surface can impart stealth properties to prolong in vivo circulation half-life and/or targeting capability to direct drug delivery to diseased tissues. The amino acid sequence of the viral coat protein can be genetically manipulated to yield protein cages of specific chemistry and morphology, while the conformation of the protein cage can be directed, via the external environment, to disassemble, then reassemble in vitro to exchange native viral genomic material with exogenous cargo. The purpose of this commentary is to evaluate current literature to assess the potential of nano-scale plant-virus-based drug delivery systems for the targeted delivery of chemotherapeutic agents.