Summary: A clinically proven drug known to block an enzyme essential for the viral entry of Coronavirus into the lungs blocks the COVID 19 (SARS-CoV-2) infection. The drug, Camostat mesilate, is a drug approved in Japan to treat pancreatic inflammation. Results suggest this drug may also protect against COVID 19. Researchers call for further clinical trials.
Viruses must enter cells of the human body to cause disease. For this, they attach to suitable cells and inject their genetic information into these cells. Infection biologists from the German Primate Center – Leibniz Institute for Primate Research in Göttingen, together with colleagues at Charité – Universitätsmedizin Berlin, have investigated how the novel coronavirus SARS-CoV-2 penetrates cells. They have identified a cellular enzyme that is essential for viral entry into lung cells: the protease TMPRSS2. A clinically proven drug known to be active against TMPRSS2 was found to block SARS-CoV-2 infection and might constitute a novel treatment option.
The findings have been published in Cell.
Several coronaviruses circulate worldwide and constantly infect humans, which normally caused only mild respiratory disease. Currently, however, we are witnessing a worldwide spread of a new coronavirus with more than 101,000 confirmed cases and almost 3,500 deaths. The new virus has been named SARS coronavirus-2 and has been transmitted from animals to humans. It causes a respiratory disease called COVID-19 that may take a severe course. The SARS coronavirus-2 has been spreading since December 2019 and is closely related to the SARS coronavirus that caused the SARS pandemic in 2002/2003. No vaccines or drugs are currently available to combat these viruses.
Stopping virus spread
A team of scientists led by infection biologists from the German Primate Centre and including researchers from Charité, the University of Veterinary Medicine Hannover Foundation, the BG-Unfallklinik Murnau, the LMU Munich, the Robert Koch Institute and the German Center for Infection Research, wanted to find out how the new coronavirus SARS-CoV-2 enters host cells and how this process can be blocked. The researchers identified a cellular protein that is important for the entry of SARS-CoV-2 into lung cells. “Our results show that SARS-CoV-2 requires the protease TMPRSS2, which is present in the human body, to enter cells,” says Stefan Pöhlmann, head of the Infection Biology Unit at the German Primate Center. “This protease is a potential target for therapeutic intervention.”
Since it is known that the drug camostat mesilate inhibits the protease TMPRSS2, the researchers have investigated whether it can also prevent infection with SARS-CoV-2. “We have tested SARS-CoV-2 isolated from a patient and found that camostat mesilate blocks entry of the virus into lung cells,” says Markus Hoffmann, the lead author of the study. Camostat mesilate is a drug approved in Japan for use in pancreatic inflammation. “Our results suggest that camostat mesilate might also protect against COVID-19,” says Markus Hoffmann. “This should be investigated in clinical trials.”
Neuroscience News would like to thank Susanne Diederich for submitting this article for inclusion on the website.
Susanne Diederich – DPZ
The image is credited to CDC.
Original Research: Open access
“SARS-CoV-2 cell entry depends on ACE2 and TMPRSS2 and is blocked by a clinically-proven protease inhibitor”. Hoffmann, M et al.
SARS-CoV-2 cell entry depends on ACE2 and TMPRSS2 and is blocked by a clinically-proven protease inhibitor
• SARS-CoV-2 uses the SARS-CoV receptor ACE2 for host cell entry
• The spike protein of SARS-CoV-2 is primed by TMPRSS2
• Antibodies against SARS-CoV spike may offer some protection against SARS-CoV-2
The recent emergence of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in China and its rapid national and international spread pose a global health emergency. Cell entry of coronaviruses depends on binding of the viral spike (S) proteins to cellular receptors and on S protein priming by host cell proteases. Unravelling which cellular factors are used by SARS-CoV-2 for entry might provide insights into viral transmission and reveal therapeutic targets. Here, we demonstrate that SARS-CoV-2 uses the SARS-CoV receptor ACE2 for entry and the serine protease TMPRSS2 for S protein priming. A TMPRSS2 inhibitor approved for clinical use blocked entry and might constitute a treatment option. Finally, we show that the sera from convalescent SARS patients cross-neutralized SARS-2-S-driven entry. Our results reveal important commonalities between SARS-CoV-2 and SARS-CoV infection and identify a potential target for antiviral intervention.