on Thursday 9 September, 2021

Some individuals may have 'superhuman' immunity to COVID-19: Studies

An illustration of COVID-19. (Unsplash, Fusion Medical Animation)
by : The Staff

Some people mount an extraordinarily powerful ‘superhuman’ or ‘bulletproof’ immune response against SARS-CoV-2, the coronavirus that causes COVID-19, a series of studies have revealed.

Their bodies not only produce very high levels of antibodies but they also make antibodies with great flexibility — likely capable of fighting off the most stringent and deadlier variants of COVID-19 as well as being potentially more effective against variants that may emerge in the future.

“One could reasonably predict that these people will be quite well protected against most — and perhaps all of — the SARS-CoV-2 variants that we are likely to see in the foreseeable future,” Paul Bieniasz, a virologist at Rockefeller University who helped lead several of the studies, was quoted in the National Public Radio (NPR) as saying.

In a study published online last month, Bieniasz and his colleagues found antibodies in these individuals that can highly neutralize the six variants of concern tested, including delta and beta, as well as several other viruses related to SARS-CoV-2, including one in bats, two in pangolins and the one that caused the first coronavirus pandemic, SARS-CoV-1.

“This is being a bit more speculative, but I would also suspect that they would have some degree of protection against the SARS-like viruses that have yet to infect humans,” Bieniasz says.

Those capable of mounting a superhuman immune response are likely to be people who have had a “hybrid” exposure to the virus - or in other words they were infected with the coronavirus in 2020 and then immunized with mRNA vaccines this year.

“Those people have amazing responses to the vaccine,” says virologist Theodora Hatziioannou at Rockefeller University, who also helped lead several of the studies.

“I think they are in the best position to fight the virus. The antibodies in these people’s blood can even neutralize SARS-CoV-1, the first coronavirus, which emerged 20 years ago. That virus is very, very different from SARS-CoV-2.”

These antibodies were even able to deactivate a virus engineered, on purpose, to be highly resistant to neutralization.

This virus contained 20 mutations that are known to prevent SARS-CoV-2 antibodies from binding to it. Antibodies from people who were only vaccinated or who only had prior coronavirus infections were essentially useless against this mutant virus.

But antibodies in people with the “hybrid immunity” could neutralize it.

These findings show how powerful the mRNA vaccines can be in people with prior exposure to SARS-CoV-2, says Hatziioannou.

“There’s a lot of research now focused on finding a pan-coronavirus vaccine that would protect against all future variants. Our findings tell you that we already have it.

“But there’s a catch, right?” she adds: You first need to be sick with COVID-19. “After natural infections, the antibodies seem to evolve and become not only more potent but also broader. They become more resistant to mutations within the [virus].”

Several other studies support the hypothesis

In one study, published last month in The New England Journal of Medicine, scientists analyzed antibodies generated by people who had been infected with the original SARS virus — SARS-CoV-1 — back in 2002 or 2003 and who then received an mRNA vaccine this year.

These people also produced high levels of antibodies and antibodies that could neutralize a whole range of variants and SARS-like viruses.

“Based on all these findings, it looks like the immune system is eventually going to have the edge over this virus,” says Bieniasz, of Rockefeller University.

“And if we’re lucky, SARS-CoV-2 will eventually fall into that category of viruses that gives us only a mild cold.”