Scientists have recently discovered very potent antibodies in the blood of recovered COVID-19 patients that provide powerful protection against SARS-CoV-2 by neutralising the virus’s ability to infect cells. The discovery sets the stage for clinical trials and additional tests of the antibodies, which are now being produced as potential treatments and preventives for COVID-19.

Ideally, antibody-based injections would be given to patients in the early stage of COVID-19 to reduce the SARS-CoV-2 viral effect and protect against severe disease. The antibodies also may be used to provide temporary, vaccine-like protection against the coronavirus infection for healthcare workers, elderly people and others who are suspected of a recent exposure to the coronavirus. But respond poorly to traditional vaccines.

If the antibodies are effective, they can then be mass-produced using biotech methods – it has already been demonstrated successfully against Ebola virus and the pneumonia-causing respiratory syncytial virus (RSV).

The new collaborative project, led by groups at Scripps Research Institute in California, US, used antibody-containing blood samples from patients who had recovered from mild-to-severe COVID-19 to see if it could bind to and strongly block the coronavirus from infecting test cells. The scientists had earlier developed test cells that express ACE2, the receptor that SARS-CoV-2 uses to get into human cells.

The scientists were fortunately able to isolate more than 1,000 distinct antibody-producing immune cells, called B cells, each of which produced a distinct anti-SARS-CoV-2 antibody. Additionally, by screening these antibodies individually, the team identified several that, even in tiny quantities, could effectively block the virus in test cells, and protect hamsters against heavy viral exposure.

“It has been a tremendous collaborative effort, and we’re now focused on making large quantities of these promising antibodies for clinical trials,” said Dr. Thomas Rogers, an adjunct assistant professor in the Department of Immunology & Microbiology at Scripps Research.

“We intend to make the antibodies available to those who need them most, including people in low- and middle-income countries,” revealed Elise Landais, an IAVI principal scientist also based in the US.