Antibodies could be an effective weapon in the fight against coronavirus. Researchers therefore examine the blood of those who have recovered and find many different antibodies in it. Among them are a few promising candidates who are directly attacking the virus.
Antibodies are not all antibodies, researchers are aware of this. The human body’s immune response to an intruder is complex. Nevertheless, researchers worldwide hope that with the help of suitable antibodies, Covid 19 patients can help protect healthy people and thus be able to intervene successfully shortly after contact with an infected person.
For this reason, researchers from the German Center for Infection Research (DZIF) and the University Hospital Cologne have set themselves the task of decoding parts of the development of these antibodies and checking their effectiveness against Covid-19. “Our goal was to better understand the immune response Sars-CoV-2 and at the same time to identify highly potent antibodies that can be used as a drug for passive immunization or for the therapy of Covid-19,” explains Professor Florian Klein, director of the institute for virology at Cologne University Hospital and project manager at DZIF in one Message.
Researchers from several universities and the Weizmann Institute of Science in Israel have found more than 4000 specific, so-called B cells in the blood of Sars-CoV-2 infected and examined their effectiveness. It was possible to obtain 255 antibodies that can bind to Sars-CoV-2. However, not all of these antibodies were able to prevent infection in the cell cultures that were treated with them in the laboratory. Only the antibodies that dock onto the tip of the so-called “spike protein” can render the virus harmless. 28 of the 255 made it. They are “therefore called neutralizing antibodies,” writes the “Deutsche Ärzteblatt” to.
Antibody blueprint in B cells
Antibodies are produced by the so-called B cells. They are a reaction of the body to a pathogen that they are supposed to attack and eliminate. Once they are formed, they can protect against new infection. The blueprint of the antibodies is in the B cells. The researchers therefore isolated the B cells from the blood of recovered and asymptomatic Sars-CoV-2 infected and added cell cultures. So it is possible to produce the effective antibodies in an unlimited amount.
In addition, the scientists also found what they were looking for in blood donations from before the pandemic. They found similar antibodies in them and believe that these have formed after infections with other coronaviruses. This is an indication that people have been infected with coronaviruses for some time, but they only cause a mild course of the disease or no symptoms.
The duration of effectiveness remains unclear
“We assume that such antibodies are effective for several weeks and could protect against illness during this time,” says Christoph Kreer, who carried out the tests in Cologne together with Matthias Zehner. “A special feature of the neutralizing antibodies found here is that they hardly show any signs of a long maturation process. This means that they only had to adapt a little to be able to effectively recognize and neutralize the virus,” adds Zehner.
The antibodies were raised in a total of 7 patients from the 8th to the 36th day after diagnosis. This may have been responsible for the mild course of the infection in the test persons: five people fell ill only slightly with cough, fever and breathing difficulties, two were completely without symptoms. The effectiveness of the antibodies is to be tested in clinical studies this year. If they prove to be safe and effective, then it is conceivable to use them not only as a remedy for Covid-19, but also as protection against a Sars-CoV-2 infection. The researchers also believe that the use of post-exposure prophylaxis, or PEP for short, is possible. The antibody preparations could then be used to protect people who had contact with Sars-CoV-2 infected people. PEP is already successfully used as a method with HI viruses.
The Results the researchers were published in the specialist magazine “Cell”.
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