'Stealth’ and ‘camouflage’ coatings of plant virus-based nanoparticles

N.F. Steinmetz, A.S. Pitek, S.A. Jameson, F.A. Veliz
Case Western Reserve University,
United States

Keywords: plant virus-based nanoparticles, imaging, drug delivery, 'stealth’ and ‘camouflage’ coatings

Summary:

'Stealth’ and ‘camouflage’ coatings of plant virus-based nanomedicines Nicole F. Steinmetz, Andrzej S. Pitek, S.A. Jameson, Frank A. Veliz Departments of Biomedical Engineering, Radiology, Materials Science and Engineering, Macromolecular Science and Engineering, and Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA. Email: nicole.steinmetz@case.edu Nanoscale engineering has the potential to revolutionize the way we prevent, detect and treat diseases. Viruses have played a special role in these developments because they can function as naturally occurring, pre-fabricated nanoscaffolds that have unique properties. The particles are highly uniform and monodisperse. Genetic and chemical engineering can be applied to introduce hundreds to thousands of copies of targeting ligands, therapeutics and imaging moieties – to impart new functionalities for application in molecular imaging and drug delivery. Nevertheless, as with other nanotechnologies, the formation of a protein corona upon intravenous administration can tag the nanocarrier for clearance by the mononuclear phagocyte system (MPS), resulting in short circulation half-lives and non-specific sequestration in non-targeted organs. PEG chain coatings have been traditionally applied to nanocarriers to ‘shield’ the particles and decrease opsonization and sequestration in MPS organs, therefore increasing the pharmacokinetics and function. However, due to increasing application of PEG in cosmetics and other industries, prevalence of anti-PEG antibodies has been reported, which may limit the utility of PEG in its application in nanomedicine. Alternative strategies are needed to tailor the in vivo properties of (plant virus-based) nanocarriers. We demonstrate the use of ‘self’ proteins, such as serum albumin, as a viable alternative: using a plant virus-based scaffold as a testbed, we demonstrate effective ‘camouflage’ of the nanocarriers resulting in a ‘stealth’ effect which is more effective compared PEG coatings.