Scientists in the UK believe they have identified a protein on the surface of human cells that makes coronavirus “highly infectious”.
And University of Bristol researchers say the findings, published in the journal Science, could help in developing antiviral treatments that could block the “newly discovered interaction between virus and host”.
Called neuropilin-1, this protein is thought to help Sars-CoV-2, the virus that causes Covid-19, rapidly spread across human cells.
The team said: “To defeat Covid-19 we will be relying on an effective vaccine and an arsenal of anti-viral therapeutics.
“Our discovery of the binding of the Sars-CoV-2 Spike to neuropilin-1 and its importance for viral infectivity provides a previously unrecognised avenue for anti-viral therapies to curb the current Covid-19 pandemic.”
Sars-CoV-2 is thought to infect humans by first attaching itself to the surface of human cells that line the respiratory tract, using what is known as the “spike” protein.
Once attached, the virus invades the cell and makes multiple copies of itself which are then released into the body, causing Covid-19.
The researchers said that understanding the process by which the virus’s spike protein recognises human cells is “central to the development of antiviral therapies and vaccines to treat Covid-19”.
The team discovered that Sars-CoV-2 recognises neuropilin-1 on the surface of human cells to facilitate viral infection.
They said: “In looking at the sequence of the Sars-CoV-2 spike protein we were struck by the presence of a small sequence of amino acids that appeared to mimic a protein sequence found in human proteins which interact with neuropilin-1.
“This led us to propose a simple hypothesis: could the spike protein of Sars-CoV-2 associate with neuropilin-1 to aid viral infection of human cells?
“Excitingly, in applying a range of structural and biochemical approaches we have been able to establish that the spike protein of Sars-CoV-2 does indeed bind to neuropilin-1.
“We were able to show that the interaction serves to enhance Sars-CoV-2 invasion of human cells grown in cell culture.”
The team said that, by using monoclonal antibodies, which are lab-created proteins that resemble naturally occurring antibodies, or a drug that blocks the interaction of neuropilin-1 with the coronavirus, they were able to reduce the virus’s ability to infect human cells.
They added: “This serves to highlight the potential therapeutic value of our discovery in the fight against Covid-19.”