Characterization of VSV-GP morphology by cryo-EM imaging and SEC-MALS

Area of Science:

• Virology
• Nanotechnology
• Biophysics

Background:

• Vesicular stomatitis virus expressing lymphocytic choriomeningitis virus glycoprotein (VSV-GP) is a key platform for oncolytic viruses and cancer vaccines.
• Understanding VSV-GP particle morphology is crucial for optimizing its therapeutic applications.

Purpose of the Study:

• To directly visualize and characterize the morphology of VSV-GP particles.
• To develop and validate high-throughput methods for analyzing VSV-GP particle subpopulations.

Main Methods:

• Cryoelectron microscopy (cryo-EM) was used for direct visualization of VSV-GP particles.
• Size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS) was employed as an orthogonal, higher-throughput method.
• A novel shape-based separation mechanism was utilized in SEC-MALS analysis.

Main Results:

• Cryo-EM revealed several distinct subpopulations of VSV-GP particle morphologies.
• Quantitative analysis of subpopulations allowed for comparative profiling of different VSV-GP samples.
• SEC-MALS effectively characterized the morphological profile of VSV-GP particles based on shape.

Conclusions:

• Complementary techniques of cryo-EM and SEC-MALS provide comprehensive analysis of VSV-GP morphology.
• These methods are valuable for characterizing VSV-GP and can be applied to other non-spherical viruses or nanoparticles.
• The findings support the advancement of VSV-GP as a platform for cancer therapies.