TMPRSS2 and furin are both essential for proteolytic activation and spread of SARS-1 CoV-2 in human airway epithelial cells and provide promising drug targets

Dorothea Bestle, Miriam Ruth Heindl, Hannah Limburg, Thuy Van Lam van, Oliver Pilgram, Hong Moulton, David A. Stein, Kornelia Hardes, Markus Eickmann, Olga Dolnik, Cornelius Rohde, Stephan Becker, Hans-Dieter Klenk, Wolfgang Garten, Torsten Steinmetzer, Eva Bottcher-Friebertshauser

10.1101/2020.04.15.042085

Research curated

Abstract

In December 2019, a novel coronavirus named SARS-CoV-2 first reported in Wuhan, China, emerged and rapidly spread to numerous other countries globally, causing the current pandemic. SARS-CoV-2 causes acute infection of the respiratory tract (COVID-19) that can result in severe disease and lethality. Currently, there is no approved antiviral drug for treating COVID-19 patients and there is an urgent need for specific antiviral therapies and vaccines. In order for SARS-CoV-2 to enter cells, its surface glycoprotein spike (S) must be cleaved at two different sites by host cell proteases, which therefore represent potential drug targets. In the present study we investigated which host cell proteases activate the SARS-CoV-2 S protein in Calu-3 human airway epithelial cells. We show that S can be cleaved by both the proprotein convertase furin at the S1/S2 site and the transmembrane serine protease 2 (TMPRSS2) at the S2 site. We demonstrate that TMPRSS2 is essential for activation of SARS-CoV-2 S in Calu-3 cells through antisense-mediated knockdown of TMPRSS2 expression. Further, we show that SARS-CoV-2 replication can be efficiently inhibited by two synthetic inhibitors of TMPRSS2 and also by the broad range serine protease inhibitor aprotinin. Additionally, SARS-CoV-2 replication was also strongly inhibited by the synthetic furin inhibitor MI-1851. Combining various TMPRSS2 inhibitors with MI-1851 produced more potent antiviral activity against SARS-CoV-2 than an equimolar amount of any single serine protease inhibitor. In contrast, inhibition of endosomal cathepsins by E64d did not affect virus replication. Our data demonstrate that both TMPRSS2 and furin are essential for SARS-CoV-2 activation in human airway cells and are promising drug targets for the treatment of COVID-19 either by targeting one of these proteases alone or by a combination of furin and TMPRSS2 inhibitors. Therefore, this approach has a high therapeutic potential for treatment of COVID-19.

Source: BioRxiv

Related molecules

Name	Synonyms	Genes
Furin		FURIN
Transmembrane serine 2	TMPRSS2, Serine protease 10	TMPRSS2, PRSS10
MI-1900	peptide mimetic inhibitors
E-64d	(2S,3S)-trans-epoxysuccinyl-L-leucylamido-3-methylbutane ethyl ester, aloxistatin, EP-453

Related interactions

Target	Drug	Type	Result
Transmembrane serine 2	Aprotinin	In vitro	positive
Transmembrane serine 2	MI-432	In vitro	positive
Transmembrane serine 2	MI-1900	In vitro	positive
Furin	MI-1851	In vitro	positive
Furin	E-64d	In vitro	negative