‘It’s something I have never seen’: How the Covid-19 virus hijacks cells
Recent studies show that the virus seizes control of genes in human cells and changes how segments of DNA are read, doing so in a way that might explain why the elderly are more likely to die of Covid-19 and why antiviral drugs might not only save the lives of sick patients but may also prevent severe disease if taken before infection.
“It’s something I have never seen in my 20 years of studying viruses,” said virologist Benjamin tenOever of the Icahn School of Medicine at Mount Sinai, referring to how SARS-CoV-2, the virus that causes Covid-19, hijacks human cell genomes.
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----------------------------------------------------------------------------------In fact, the Icahn School team found no interferons in the lung cells of Covid-19 patients. Without interferons, tenOever said, “there is nothing to stop the virus from replicating and festering in the lungs forever.”
That causes lung cells to emit even more “call-for-reinforcement” genes, summoning more and more immune cells. Now the lungs have macrophages and neutrophils and other immune cells “everywhere,” tenOever said, causing such runaway inflammation “that you start having inflammation that induces more inflammation.”
At the same time, unchecked viral replication kills lung cells involved in oxygen exchange. “And suddenly you’re in the hospital in severe respiratory distress,” he said.
In elderly people, as well as those with diabetes, heart disease, and other underlying conditions, the call-to-arms part of the immune system is weaker than in younger, healthier people, even before the coronavirus arrives. That reduces even further the cells’ ability to knock down virus replication with interferons, and imbalances the immune system toward the dangerous inflammatory response.
The discovery that SARS-CoV-2 strongly suppresses infected cells’ production of interferons has raised an intriguing possibility: that taking interferons might prevent severe Covid-19 or even prevent it in the first place, said Vineet Menachery of the University of Texas Medical Branch.
In a study of human cells growing in lab dishes, described in a preprint (not peer-reviewed or published in a journal yet), he and his colleagues also found that SARS-CoV-2 “prevents the vast amount” of interferon genes from turning on. But when cells growing in lab dishes received the interferon IFN-1 before exposure to the coronavirus, “the virus has a difficult time replicating.”
After a few days, the amount of virus in infected but interferon-treated cells was 1,000- to 10,000-fold lower than in infected cells not pre-treated with interferon. (The original SARS virus, in contrast, is insensitive to interferon.)
Ending the pandemic and preventing its return is assumed to require an effective vaccine to prevent infection and antiviral drugs such as remdesivir to treat the very sick, but the genetic studies suggest a third strategy: preventive drugs.
It’s possible that treatment with so-called type-1 interferon “could stop the virus before it could get established,” Menachery said.
Giving drugs to healthy people is always a dicey proposition, since all drugs have side effects — something considered less acceptable than when a drug is used to treat an illness. “Interferon treatment is rife with complications,” Menachery warned. The various interferons, which are prescribed for hepatitis, cancers, and many other diseases, can cause flu-like symptoms.
But the risk-benefit equation might shift, both for individuals and for society, if interferons or antivirals or other medications are shown to reduce the risk of developing serious Covid-19 or even make any infection nearly asymptomatic.
Interferon “would be warning the cells the virus is coming,” Menachery said, so such pretreatment might “allow treated cells to fend off the virus better and limit its spread.” Determining that will of course require clinical trials, which are underway.
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really interesting article but if ever there was a drug in search of a disease it is interferon. is there no disease that it hasnt been claimed to cure?
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CYDY time to acknowledge it has a place in treatment…
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You discuss interferon as preventing infection, but treating healthy individuals throughout the general population means there could be widespread side effects. What about treating patients after Covid-19 infection is identified? Might that slow the replication of the virus and reduce the likelihood of developing severe disease and/or death?
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absolutely amazing reporting THANK YOU
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Fascinating. If Trump sees this he will demand interferon for himself and proclaim it as another cure, even though it is not approved.
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Oh Lord… can you libs give the whole Trump thing a rest? Here’s an awesome breakthrough of study and you go political. I got an idea … SHUT UP.
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Is there anything in my post that precludes approval? If so, I’d like to know why. I posted at 10:38am and you’ve since approved posts at 12:19pm and 1:26pm.
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