Full‐length G glycoprotein directly extracted from rabies virus with detergent and then stabilized by amphipols in liquid and freeze‐dried forms. Issue 11 (5th August 2021)

• Record Type: Journal Article
• Authors: Clénet, Didier; Clavier, Léna; Strobbe, Benoît; Le Bon, Christel; Zoonens, Manuela; Saulnier, Aure
• Is Part Of: Biotechnology and bioengineering. Volume 118:Issue 11(2021)
• Page Start: 4317
• Page End: 4330
• Publication Date: 2021-08-05
• Subjects: A8‐35 formulation study -- amphipol‐stabilized integral membrane protein -- G glycoprotein from rabies virus -- stable freeze‐dried A8‐35 formulation; Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.27900
• Languages: English
• ISSNs: 0006-3592

Abstract

Abstract: Pathogen surface antigens are at the forefront of the viral strategy when invading host organisms. These antigens, including membrane proteins (MPs), are broadly targeted by the host immune response. Obtaining these MPs in a soluble and stable form constitutes a real challenge, regardless of the application purposes (e.g. quantification/characterization assays, diagnosis, and preventive and curative strategies). A rapid process to obtain a native‐like antigen by solubilization of a full‐length MP directly from a pathogen is reported herein. Rabies virus (RABV) was used as a model for this demonstration and its full‐length G glycoprotein (RABV‐G) was stabilized with amphipathic polymers, named amphipols (APols). The stability of RABV‐G trapped in APol A8‐35 (RABV‐G/A8‐35) was evaluated under different stress conditions (temperature, agitation, and light exposure). RABV‐G/A8‐35 in liquid form exhibited higher unfolding temperature (+6°C) than in detergent and was demonstrated to be antigenically stable over 1 month at 5°C and 25°C. Kinetic modeling of antigenicity data predicted antigenic stability of RABV‐G/A8‐35 in a solution of up to 1 year at 5°C. The RABV‐G/A8‐35 complex formulated in an optimized buffer composition and subsequently freeze‐dried displayed long‐term stability for 2‐years at 5, 25, and 37°C. This study reports for the first time that a natural full‐length MP extracted from a virus, complexed to APols and subsequently freeze‐dried, displayed long‐term antigenic stability, without requiring storage under refrigerated conditions. Abstract : A rapid process to obtain a native‐like antigen by solubilization of a full‐length membrane protein (MP) directly from a pathogen is reported herein, using rabies virus (RABV) as a model. Its full‐length G glycoprotein (RABV‐G) was stabilized with amphipols (APols), confirming the ability of such amphipathic polymers to stabilize pathogen surface MPs. RABV‐G/APol exhibited a high thermal stability of G specific antigenicity in a defined freeze‐dried formulation for at least 2 years under storage conditions from 5°C to 37°C.