YERUSHALAYIM — Antibodies isolated from the immune system of recovered COVID-19 patients are effective in neutralizing all known strains of the virus, including the Delta and the Omicron variants, an Israeli research team announced on Wednesday.

The researchers, at Tel Aviv University, said their discovery may eliminate the need for repeated booster vaccinations and strengthen the immune system of populations at risk.

The present study is a continuation of a research conducted in October 2020, at the height of the COVID-19 crisis. At that time, Dr. Natalia Freund and her colleagues sequenced all the B immune system cells from the blood of people who had recovered from the original COVID strain in Israel, and isolated nine antibodies that the patients produced. The researchers now found that some of these antibodies are very effective in neutralizing Delta and Omicron.

Dr. Freund: “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.

“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 two antibodies, cloned in Dr. Freund’s laboratory at TAU, were sent for tests to check their effectiveness against live viruses in laboratory cultures at the University of California San Diego, and against pseudoviruses in the laboratories of the Faculty of Medicine of Bar-Ilan University in the Galil; the results were identical and equally encouraging in both tests.

Also collaborating in the work was Dr. Ben Croker of the University of California San Diego and Prof. Ye Xiang of Tsinghua University in Beijing.

Source: Hamodia