Researchers from Europe have identified a fully human monoclonal antibody which blocks the SARS-CoV-2 virus (the one that causes COVID-19) from entering cultured cells.

The team of researchers, which are affiliated with Utrecht University, Erasmus Medical Center, and Harbour BioMed (HBM), built on previous work related to antibodies targeting SARS-CoV-1, which caused an outbreak in 2002-2003.

“Using this collection of SARS-CoV antibodies, we identified an antibody that also neutralizes infection of SARS-CoV-2 in cultured cells. Such a neutralizing antibody has potential to alter the course of infection in the infected host, support virus clearance or protect an uninfected individual that is exposed to the virus,” said Berend-Jan Bosch, Associate Professor, Research leader at Utrecht University, and co-lead author of the new study published in Nature Communications.

The newly identified antibody binds to a domain shared by both SARS viruses, neutralizing them. Unlike antibodies derived from other organisms, the one used in the study is “fully human”, minimizing immune-related side effects.

Monoclonal antibodies (mAbs) are antigen-recognizing glycoproteins that are made by identical immune cells (are clones of a unique parent cell). These antibodies are used in a number of therapies for health conditions such as autoimmune disorders, infectious diseases, and cancers.

This also means that treatments based on the antibody ought to be safe, although that would, of course, have to be tested in clinical trials. The fact that the therapeutic effects of the human antibody have been demonstrated only in-vitro is an important limitation that doesn’t necessarily mean it will work in-vivo.

“This is groundbreaking research,” said Dr. Jingsong Wang, Founder, Chairman & Chief Executive Officer of HBM. “Much more work is needed to assess whether this antibody can protect or reduce the severity of disease in humans. We expect to advance development of the antibody with partners. We believe our technology can contribute to addressing this most urgent public health need and we are pursuing several other research avenues.”