Lab Just Made a More Dangerous Cov Virus
By CNBS News
If SARS-CoV-2 has frazzled your nerves, I have bad news for you. Scientists are already cooking up more virulent and lethal versions. In a January 22, 2021, Twitter post, biotech entrepreneur Yuri Deigin highlighted a study posted on the preprint server bioRxiv at the end of December 2020, saying:
“Ok, the prize for the craziest and most dangerous gain-of-function research goes out to Italian virologists who took SARS[-CoV-]2 and passaged it in vitro in the presence of neutralizing antibodies.2 It quickly obliged and mutated to escape them. Yay for a novel, more dangerous SARS3!”
“Passaging” refers to a genetic engineering technique where a virus is grown in a series of different animal tissue cultures. With each “pass,” the virus will mutate slightly, gaining different functions.
Serial Passaging Allows Virus to Jump Species
As just one example, a potential outcome of this somewhat crude technique (considering the genetic engineering technology now available) would be that the virus could gain the ability to infect a host species it could not infect before. Some experts have speculated that this might be one way in which SARS-CoV-2 was created.
In an in-depth article published in New York magazine January 4, 2021, Nicholson Baker reviewed the history of viral gain-of-function research, providing the following example of serial passaging:
“Baric … described in this early paper how his lab was able to train a coronavirus, MHV, which causes hepatitis in mice, to jump species, so that it could reliably infect BHK (baby-hamster kidney) cell cultures.
They did it using serial passaging: repeatedly dosing a mixed solution of mouse cells and hamster cells with mouse-hepatitis virus, while each time decreasing the number of mouse cells and upping the concentration of hamster cells.
At first, predictably, the mouse-hepatitis virus couldn’t do much with the hamster cells, which were left almost free of infection, floating in their world of fetal-calf serum.
But by the end of the experiment, after dozens of passages through cell cultures, the virus had mutated: It had mastered the trick of parasitizing an unfamiliar rodent. A scourge of mice was transformed into a scourge of hamsters …”
Scientists Have Created Coronavirus That Escapes Antibodies
So, what exactly have they come up with now? As summarized by Deigin, researchers serial passaged live SARS-CoV-2 in plasma obtained from a recovered COVID-19 patient that had a high amount of neutralizing antibodies in it.
For clarification, you have two types of antibodies. Neutralizing antibodies are, as the name implies, antibodies that neutralize (kill) viruses and prevent infection, whereas binding antibodies cannot prevent infection.
The neutralizing antibodies in the plasma successfully and completely neutralized the virus during the first seven passages, but then, the virus mutated to evade the antibodies. As explained by the authors:
“The plasma fully neutralized the virus for 7 passages, but after 45 days, the deletion of F140 in the spike N-terminal domain (NTD) N3 loop led to partial breakthrough. At day 73, an E484K substitution in the receptor-binding domain (RBD) occurred, followed at day 80 by an insertion in the NTD N5 loop containing a new glycan sequon, which generated a variant completely resistant to plasma neutralization.”
In other words, they created a SARS-CoV-2 variant that bypasses acquired immunity and negates the immunity you normally would have after recovering from the infection. As such, it could be extremely lethal.
“Computational modeling predicts that the deletion and insertion in loops N3 and N5 prevent binding of neutralizing antibodies,” the authors say, adding:
“The recent emergence in the United Kingdom and South Africa of natural variants with similar changes suggests that SARS-CoV-2 has the potential to escape an effective immune response and that vaccines and antibodies able to control emerging variants should be developed.”
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