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bioRxiv · 10.1101/2023.10.03.560628

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

Ikeda, T.·Begum, M. M.·Ichihara, K.·Takahashi, O.·Nasser, H.·Jonathan, M.·Tokunaga, K.·Yoshida, I.·Nagashima, M.·Sadamasu, K.·Yoshimura, K.·Sato, K.
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Abstract

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. In this study, we investigated the virological parameters of eleven previous variants of concern (VOCs) and variants of interest (VOIs) correlating with S protein fusogenicity. 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 of newly emerged SARS-CoV-2 variants.

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Ikeda, T., Begum, M. M., Ichihara, K., Takahashi, O., Nasser, H., Jonathan, M., Tokunaga, K., Yoshida, I., Nagashima, M., Sadamasu, K., Yoshimura, K., Sato, K.. 2023-10-03. Virological characteristics correlating with SARS-CoV-2 spike protein fusogenicity. https://doi.org/10.1101/2023.10.03.560628

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