Jun 16, 2020 12:00:00

'Antibodies that can repel most SARS coronaviruses' are separated from former patients with new-type coronavirus infection

A very potent

antibody against the novel coronavirus (SARS-CoV-2) was isolated from the body of a former patient who recovered from the novel coronavirus infection (COVID-19). In addition, in the course of the study, effective antibodies against most SARS coronaviruses (SARS-CoV-1) as well as SARS-CoV-2 were found, so future widespread severe acute respiratory syndrome (SARS) It is expected that vaccines and remedies that are compatible with will emerge.

Isolation of potent SARS-CoV-2 neutralizing antibodies and protection from disease in a small animal model | Science
https://science.sciencemag.org/content/early/2020/06/15/science.abc7520

Super-potent human antibodies protect against COVID-19 in animal tests | Scripps Research
https://www.scripps.edu/news-and-events/press-room/2020/20200615-burton-covid19antibody.html

The isolation of antibodies that could lead to the development of COVID-19 vaccines and therapeutics was successfully accomplished by Thomas Rogers, a research team studying immunology at the Scripps Research Institute in the United States. The research team took blood samples from former COVID-19 patients who recovered from various symptoms from mild to severe and examined the immune cells contained in them.

There are many types of immune cells, but the research team paid particular attention to those called B cells . B cells are immune cells that produce antibodies that attack viruses and other pathogens in the body, and some remain in the body as 'memory B cells' even after the pathogen disappears from the body. In general, 'immunized against infectious disease' means that these memory B cells are present, and vaccination is also based on this mechanism.

There is only one type of antibody that one type of B cell can produce. Therefore, the research team isolated more than 1000 types of B cells from patients, extracted antibody genes from those B cells, and synthesized antibodies in the laboratory.

In addition, the research team developed cells for testing that express a protein called ACE2, which is a receptor used when SARS-CoV-2 enters human cells, in order to efficiently investigate the effect of many antibodies found. We added SARS-CoV-2 and antibodies to the test cells and screened which antibodies protect human cells from SARS-CoV-2. This work allowed us to identify multiple promising antibodies in as little as 10 days after taking a blood sample.

The research team then added two antibodies to cells infected with SARS-CoV-2 and SARS-CoV-1, and identified two types of antibodies that were effective against both. This antibody is called ' neutralizing antibody ' because it can suppress the infectivity of the virus. The two neutralizing antibodies discovered by the research team were able to protect hamsters from SARS-CoV-2 even in experiments using hamsters infected with very high levels of SARS-CoV-2.

by digital_image_fan

Elise Landais, co-author of the paper, said: ``We intend to make the antibodies available to people in low- and middle-income countries who need the most treatment for COVID-19, including those in low- and middle-income countries. That's it.' 'We are currently focusing on how to mass-produce antibodies for clinical trials,' said lead author Rogers.

According to the research team, the antibody discovered this time will start clinical trials as early as January 2021 after safety is confirmed by cultured cells and animal experiments.

In addition, during the course of this research, an antibody effective against not only COVID-19 but also ordinary SARS coronavirus was found, says Landais. , We can expect to find neutralizing antibodies that provide at least partial protection.'