# Virus glycoprotein nanodisc platform for vaccine analytics

## TL;DR

This paper introduces a nanodisc platform to study virus glycoproteins for vaccine development, enabling detailed analysis of their structure and antibody interactions.

## Contribution

The novel contribution is a scalable and reproducible nanodisc platform for assembling transmembrane glycoproteins to accelerate vaccine development.

## Key findings

- Nanodiscs enable structural analysis of HIV MPER-targeting immunogens with cryo-EM at 3.5 Å resolution.
- The platform supports ex vivo B cell sorting and SPR binding assays for antibody response analysis.
- The method is demonstrated to be broadly applicable by characterizing Ebola virus glycoprotein nanodiscs.

## Abstract

Transmembrane glycoproteins of enveloped viruses are targets of neutralizing antibodies and essential vaccine antigens. mRNA-LNP technology allows in vivo expression of transmembrane glycoproteins, but in vitro biophysical characterization of transmembrane antigens and analysis of post-immunization antibody responses typically rely on soluble proteins. Here, we present a platform for assembling transmembrane glycoprotein vaccine candidates into lipid nanodiscs. We demonstrate the utility of nanodiscs in HIV membrane proximal external region (MPER)-targeting vaccine development by binding assays using surface plasmon resonance (SPR), ex vivo B cell sorting with fluorescence-activated cell sorting (FACS), and by determining the structure of a prototypical HIV MPER-targeting immunogen nanodisc in complex with three broadly neutralizing antibodies (bnAbs), including MPER bnAb 10E8, to 3.5 Å by cryogenic electron microscopy (cryo-EM), providing a template for structure-based immunogen design. To demonstrate general applicability we characterize Ebola virus glycoprotein nanodiscs. Overall, the platform offers a tool for accelerating development of next-generation vaccines.

Many viral vaccine antigen candidates are transmembrane glycoproteins, and their development requires methods which allow their biophysical characterization. Here authors present an optimized nanodisc assembly platform which provides reproducible, scalable, and accurate replication of the vaccine candidates for detailed analysis.