Fusogenic Viral Protein-Based Near-Infrared Active Nanocarriers for Biomedical Imaging

Abstract

An effective drug delivery system (DDS) relies on an efficient cellular uptake and faster intracellular delivery of theranostic agents, bypassing the endosomal mediated degradation of the payload. The use of viral nanoparticles (VNPs) permits such advancement, as the viruses are naturally evolved to infiltrate the host cells to deliver their genetic material. As a proof of concept, we bioengineered the vesicular stomatitis virus glycoprotein (VSV-G)-based near-infrared (NIR) active viral nanoconstructs (NAVNs) encapsulating indocyanine green dye (ICG) for NIR bioimaging. NAVNs are spherical in size and have the intrinsic cellular-fusogenic properties of VSV-G. Further, the NIR imaging displaying higher fluorescence intensity in NAVNs treated cells suggests enhanced cellular uptake and delivery of ICG by NAVNs compared to the free form of ICG. The overall study highlights the effectiveness of VSV-G-based VNPs as an efficient delivery system for NIR fluorescence imaging.

Emerging Biomedical Applications of the Vesicular Stomatitis Virus Glycoprotein

“…The NIR imaging showed enhanced fluorescence intensity and improvement in the signal-to-noise ratio (SNR) of NAVN-treated cells compared to free ICG. Even after 72 h of treatment with cells, the encapsulated form was ∼60% optically active while the free ICG activity fell below ∼20% . This approach also showed dramatic improvement in the circulating half-life of ICG in preclinical mouse model studies.…”

“…Even after 72 h of treatment with cells, the encapsulated form was ∼60% optically active while the free ICG activity fell below ∼20%. 18 This approach also showed dramatic improvement in the circulating half-life of ICG in preclinical mouse model studies. The improved circulating half-life of ICG was partly because of the stability of the formulation in blood circulation aided by sustained release of the drug from VLPs over time.…”

“…The use of VSV-G-based nanoparticles has recently been demonstrated as an improved imaging carrier. 18 Currently, fluorescence imaging has emerged as an effective noninvasive technique for cancer diagnosis in preclinical settings. However, it is difficult to look into the human body beyond penetration depth (1 mm) using visible radiation.…”

“…The success of the technique rests on surface modification with appropriate ligands such as metal nanoparticles and contrast agents. The use of VSV-G-based nanoparticles has recently been demonstrated as an improved imaging carrier . Currently, fluorescence imaging has emerged as an effective noninvasive technique for cancer diagnosis in preclinical settings.…”

Virus-like nanoparticles as a theranostic platform for cancer

“…In contrast, non-eVLPs can be produced in both eukaryotic and prokaryotic expression systems owing to their relatively easy production and purification processes ( Kushnir et al, 2012 ; Chen et al, 2020 ; Nooreai et al, 2021 ). Therefore, non-eVLPs have been mainly utilized as nanocarriers for therapeutics and diagnostics ( Shan et al, 2018a ; Shan et al, 2018b ; Hu et al, 2019a ; Hu and Steinmetz, 2020a ; Bishnoi et al, 2021 ; Lu et al, 2021 ).…”