TEL-AVIV, Israel — Groundbreaking new discoveries by a team at Tel-Aviv University may make the ongoing discourse over COVID-19 vaccines a moot point. Scientists have identified and isolated two antibodies capable of neutralizing all currently known strains of COVID (including Omicron) with up to 95 percent efficiency.
Study authors explain that targeted treatments with these antibodies and their delivery to the body in high concentrations may function as an effective substitute or replacement for vaccines – especially among members of the population at high risk of contracting COVID or those with weakened immune systems. While a lot has to happen to reach this point, researchers say antibody treatments could possibly eliminate the need for booster shots among the entire population whenever a new variant appears.
What facilitated this incredible breakthrough? The research team isolated the antibodies from the immune systems of recovered COVID-19 patients.
This research was led by Dr. Natalia Freund, as well as doctoral students Michael Mor and Ruofan Lee of the Department of Clinical Microbiology and Immunology at the Sackler Faculty of Medicine. Additionally, the team collaborated with Dr. Ben Croker of the University of California San Diego, Prof. Ye Xiang of Tsinghua University in Beijing, and Prof. Meital Gal-Tanamy and Dr. Moshe Dessau of Bar-Ilan University.
Attacking COVID’s spike from a different direction
This research is actually a continuation of an earlier, preliminary project put together in October 2020 at the height of the pandemic. Back then, Dr. Freund and her colleagues sequenced all the B immune system cells from the blood of recovered patients infected with the original COVID-19 strain in Israel. That process led to the isolation of nine antibodies produced by the patients. Fast forward to today, and researchers have now found that some of those antibodies are indeed quite effective at neutralizing new coronavirus variants like Delta and Omicron.
“In the previous study, we showed that the various antibodies that are formed in response to infection with the original virus are directed against different sites of the virus. The most effective antibodies were those that bound to the virus’s ‘spike’ protein, in the same place where the spike binds the cellular receptor ACE2. Of course, we were not the only ones to isolate these antibodies, and the global health system made extensive use of them until the arrival of the different variants of the coronavirus, which in fact rendered most of those antibodies useless,” Dr. Freund says in a media release.
“In the current study, we proved that two other antibodies, TAU-1109 and TAU-2310, which bind the viral spike protein in a different area from the region where most of the antibodies were concentrated until now (and were therefore less effective in neutralizing the original strain) are actually very effective in neutralizing the Delta and Omicron variants. According to our findings, the effectiveness of the first antibody, TAU-1109, in neutralizing the Omicron strain is 92%, and in neutralizing the Delta strain, 90%. The second antibody, TAU-2310, neutralizes the Omicron variant with an efficacy of 84%, and the Delta variant with an efficacy of 97%,” the study author continues.
‘We will not have to provide booster doses’
Dr. Freund theorizes that the surprising effectiveness of the antibodies may have something to do with the evolution of the virus.
“The infectivity of the virus increased with each variant because each time, it changed the amino acid sequence of the part of the spike protein that binds to the ACE2 receptor, thereby increasing its infectivity and at the same time evading the natural antibodies that were created following vaccinations. In contrast, the antibodies TAU-1109 and TAU-2310 don’t bind to the ACE2 receptor binding site, but to another region of the spike protein – an area of the viral spike that for some reason does not undergo many mutations – and they are therefore effective in neutralizing more viral variants. These findings emerged as we tested all the known COVID strains to date,” Freund explains.
Researchers cloned the two antibodies in Dr. Freund’s laboratory at Tel Aviv University, then sent them for further tests at the University of California San Diego to measure their effectiveness against live viruses in laboratory cultures. Study authors also tested the antibodies against pseudoviruses in the laboratories of Bar-Ilan University. Results were identical across both series of tests.
Dr. Freund believes these new antibodies can revolutionize the fight against COVID-19.
“We need to look at the COVID-19 pandemic in the context of previous disease outbreaks that humankind has witnessed. People who were vaccinated against smallpox at birth and who today are 50 years old still have antibodies, so they are probably protected, at least partially, from the monkeypox virus that we have recently been hearing about. Unfortunately, this is not the case with the coronavirus. For reasons we still don’t yet fully understand, the level of antibodies against COVID-19 declines significantly after three months, which is why we see people getting infected again and again, even after being vaccinated three times,” the researcher says.
“In our view, targeted treatment with antibodies and their delivery to the body in high concentrations can serve as an effective substitute for repeated boosters, especially for at-risk populations and those with weakened immune systems. COVID-19 infection can cause serious illness, and we know that providing antibodies in the first days following infection can stop the spread of the virus. It is therefore possible that by using effective antibody treatment, we will not have to provide booster doses to the entire population every time there is a new variant,” Freund concludes.
The study is published in the journal Communications Biology.