Virological characteristics correlating with SARS-CoV-2 spike protein fusogenicity

• Published in: Frontiers in virology (online) Vol. 4
• Main Authors: Begum, MST Monira, Ichihara, Kimiko, Takahashi, Otowa, Nasser, Hesham, Jonathan, Michael, Tokunaga, Kenzo, Yoshida, Isao, Nagashima, Mami, Sadamasu, Kenji, Yoshimura, Kazuhisa, Sato, Kei, Ikeda, Terumasa
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 14.03.2024
• Subjects: fusogenicity; pathogenicity; plaque size; pseudoviral infectivity; S1/S2 cleavage efficiency; SARS-CoV-2
• ISSN: 2673-818X; 2673-818X
• DOI: 10.3389/fviro.2024.1353661

Introduction The severe acute respiratory syndrome coronavirus (SARS-CoV-2) spike (S) protein is essential in mediating membrane fusion of the virus with the target cells. Several reports demonstrated that SARS-CoV-2 S protein fusogenicity is reportedly closely associated with the intrinsic pathogenicity of the virus determined using hamster models. However, the association between S protein fusogenicity and other virological parameters remains elusive. Methods In this study, we investigated the virological parameters (e.g., S1/S2 cleavage efficiency, plaque size, pseudoviral infectivity, pseudovirus entry efficiency, and viral replication kinetics) of eleven previous variants of concern (VOCs) and variants of interest (VOIs) correlating with S protein fusogenicity. Results and discussion S protein fusogenicity was found to be strongly correlated with S1/S2 cleavage efficiency and plaque size formed by clinical isolates. However, S protein fusogenicity was less associated with pseudoviral infectivity, pseudovirus entry efficiency, and viral replication kinetics. Taken together, our results suggest that S1/S2 cleavage efficiency and plaque size could be potential indicators to predict the intrinsic pathogenicity and S protein fusogenicity of newly emerged SARS-CoV-2 variants.