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

Dongyue Xin; Leela Kurien; Katherine Briggs; Adrian Schimek; Richard Dambra; Daniel Hochdorfer; Tanja A Arnouk; Marija Brgles; Saurabh Gautam; Dominik Hotter; Johannes Solzin; Thomas Kriehuber; Joseph Ashour; Adam Vigil; Michael Hawley; Xiaorong He

doi:10.1016/j.omtm.2025.101429

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

Mol Ther Methods Clin Dev. 2025 Feb 6;33(1):101429. doi: 10.1016/j.omtm.2025.101429. eCollection 2025 Mar 13.

Authors

Dongyue Xin¹, Leela Kurien¹, Katherine Briggs¹, Adrian Schimek², Richard Dambra³, Daniel Hochdorfer⁴, Tanja A Arnouk⁴, Marija Brgles⁴, Saurabh Gautam^{2

5}, Dominik Hotter⁴, Johannes Solzin⁴, Thomas Kriehuber⁴, Joseph Ashour³, Adam Vigil³, Michael Hawley¹, Xiaorong He⁶

Affiliations

¹ Material and Analytical Sciences, Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, CT, USA.
² ViraTherapeutics GmbH, Innsbruck, Austria.
³ Drug Metabolism and Pharmacokinetics, Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, CT, USA.
⁴ Viral Therapeutics Center, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany.
⁵ Boehringer Ingelheim International GmbH, Ingelheim, Germany.
⁶ Boehringer Ingelheim Pharmaceuticals Inc., Ridgefield, CT, USA.

Abstract

Vesicular stomatitis virus expressing the glycoprotein of the lymphocytic choriomeningitis virus (VSV-GP) is a promising platform for oncolytic viruses and cancer vaccines. In this work, cryoelectron microscopy (cryo-EM) imaging was employed to directly visualize VSV-GP particles. Several different subpopulations of virus particle morphology were observed. Definition and fraction counting of subpopulations enabled quantitative comparison of subpopulation profiles between several VSV-GP samples. In developing an orthogonal method with higher throughput, we showed that the morphological profile of the VSV-GP particles can be characterized by size exclusion chromatography coupled with a multi-angle light scattering detector (SEC-MALS) based on a novel shape-based separation mechanism. Together, the two complementary techniques enable the analysis of morphological profile for VSV-GP and potentially other non-spherical viruses or nanoparticles.

Keywords: SEC-MALS; VSV-GP; analytical HPLC; cryo-EM; vesicular stomatitis virus; virus particle morphology.