tetano
Editor, Senior Moderator
iScience
. 2021 Mar 19;24(3):102170.
doi: 10.1016/j.isci.2021.102170. Epub 2021 Feb 9.
Quantitative assays reveal cell fusion at minimal levels of SARS-CoV-2 spike protein and fusion from without
Samuel A Theuerkauf[SUP] 1 [/SUP], Alexander Michels[SUP] 1 [/SUP], Vanessa Riechert[SUP] 1 [/SUP], Thorsten J Maier[SUP] 2 [/SUP], Egbert Flory[SUP] 3 [/SUP], Klaus Cichutek[SUP] 1 [/SUP], Christian J Buchholz[SUP] 1 3 [/SUP]
Affiliations
Abstract
Cell entry of the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mediated by its spike protein S. As a main antigenic determinant, S protein is in focus of various therapeutic strategies. Besides particle-cell fusion, S mediates fusion between infected and uninfected cells resulting in syncytia formation. Here, we present sensitive assay systems with a high dynamic range and high signal-to-noise ratios covering not only particle-cell and cell-cell fusion but also fusion from without (FFWO). In FFWO, S-containing viral particles induce syncytia independently of de novo synthesis of S. Neutralizing antibodies, as well as sera from convalescent patients, inhibited particle-cell fusion with high efficiency. Cell-cell fusion, in contrast, was only moderately inhibited despite requiring levels of S protein below the detection limit of flow cytometry and Western blot. The data indicate that syncytia formation as pathological consequence during coronavirus disease 2019 (COVID-19) can proceed at low levels of S protein and may not be effectively prevented by antibodies.
Keywords: Biochemical Assay; Cell Biology; Membrane Architecture.
. 2021 Mar 19;24(3):102170.
doi: 10.1016/j.isci.2021.102170. Epub 2021 Feb 9.
Quantitative assays reveal cell fusion at minimal levels of SARS-CoV-2 spike protein and fusion from without
Samuel A Theuerkauf[SUP] 1 [/SUP], Alexander Michels[SUP] 1 [/SUP], Vanessa Riechert[SUP] 1 [/SUP], Thorsten J Maier[SUP] 2 [/SUP], Egbert Flory[SUP] 3 [/SUP], Klaus Cichutek[SUP] 1 [/SUP], Christian J Buchholz[SUP] 1 3 [/SUP]
Affiliations
- PMID: 33585805
- PMCID: PMC7871100
- DOI: 10.1016/j.isci.2021.102170
Abstract
Cell entry of the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mediated by its spike protein S. As a main antigenic determinant, S protein is in focus of various therapeutic strategies. Besides particle-cell fusion, S mediates fusion between infected and uninfected cells resulting in syncytia formation. Here, we present sensitive assay systems with a high dynamic range and high signal-to-noise ratios covering not only particle-cell and cell-cell fusion but also fusion from without (FFWO). In FFWO, S-containing viral particles induce syncytia independently of de novo synthesis of S. Neutralizing antibodies, as well as sera from convalescent patients, inhibited particle-cell fusion with high efficiency. Cell-cell fusion, in contrast, was only moderately inhibited despite requiring levels of S protein below the detection limit of flow cytometry and Western blot. The data indicate that syncytia formation as pathological consequence during coronavirus disease 2019 (COVID-19) can proceed at low levels of S protein and may not be effectively prevented by antibodies.
Keywords: Biochemical Assay; Cell Biology; Membrane Architecture.