Supramolecular Encapsulation of Small-Ultrared Fluorescent Proteins in Virus-Like Nanoparticles for Noninvasive In Vivo Imaging Agents

Bioconjug Chem. 2020 May 20;31(5):1529-1536. doi: 10.1021/acs.bioconjchem.0c00190. Epub 2020 May 7.

Abstract

Icosahedral virus-like particles (VLPs) derived from bacteriophages Qβ and PP7 encapsulating small-ultrared fluorescent protein (smURFP) were produced using a versatile supramolecular capsid disassemble-reassemble approach. The generated fluorescent VLPs display identical structural properties to their nonfluorescent analogs. Encapsulated smURFP shows indistinguishable photochemical properties to its unencapsulated counterpart, exhibits outstanding stability toward pH, and produces bright in vitro images following phagocytosis by macrophages. In vivo imaging allows the biodistribution to be imaged at different time points. Ex vivo imaging of intravenously administered encapsulated smURFP reveals a localization in the liver and kidneys after 2 h blood circulation and substantial elimination after 16 h of imaging, highlighting the potential application of these constructs as noninvasive in vivo imaging agents.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Capsules
  • Hydrogen-Ion Concentration
  • Luminescent Proteins / chemistry*
  • Luminescent Proteins / metabolism
  • Mice
  • Molecular Imaging / methods*
  • Nanoparticles / chemistry*
  • Phagocytosis
  • RAW 264.7 Cells
  • Red Fluorescent Protein
  • Viruses / chemistry*

Substances

  • Capsules
  • Luminescent Proteins