Marit van Gils found powerful antibodies against the coronavirus

A researcher cannot get much better. Found powerful antibodies against the coronavirus. A publication in Science followed by a lot of media attention. Researcher Marit van Gils talks about the search in the blood of Amsterdam patients with covid.

What exactly did you find?

“We searched for antibodies in the blood of Amsterdam patients with covid-19. Anyone who becomes infected with a virus produces antibodies to disable the intruder. We collected dozens of antibodies (proteins) from the blood. Two of these turned out to be the most powerful of all antibodies against the new corona virus known to date. The idea is to produce and give those powerhouses on a large scale as medicines in the early stages of the disease, or perhaps preventively to temporarily protect people.

The idea of ​​doing this is not new. In the blood of people who have had an infectious disease are substances that can help to fight the disease in others. Blood plasma from cured patients has been used as a medicine for decades. But it is better to isolate the components responsible for this from the blood and give only those to patients. Numerous antibodies have now been found. We were one of the first to make antibodies from covid-19 patients. Researchers all over the world have now done the same. Our antibodies are among the most powerful that have been found. ”

Other research shows that blood plasma from covid-19 patients does little in the seriously ill and that the antibodies disappear quickly after the disease. What does this outcome mean?

“It is not surprising that blood plasma does not always work for patients. It teaches us exactly when to administer the antibodies during the disease process. In a later phase of the disease, when the patient is in intensive care, the problem is not the virus, but an immune response in the body that has gotten out of hand. Then antibodies are no longer useful. You expect the greatest effect if they are given shortly after infection. Or as a prophylaxis to prevent vulnerable groups from contracting the disease. Antibodies have a short lifespan, about two weeks. That is not a problem if we give them to recently infected people, but for protection you prefer that antibodies remain longer present. A vaccine that triggers an immune response in the body can achieve this, but we are also working on ways to extend the life of our antibodies in the body. We expect to come up with antibodies that can remain effective for three months.

” How do you find the right antibodies in your blood, where cells and proteins are crawling? “

At Amsterdam UMC we have a lot of experience with antibodies against HIV, the virus that leads to AIDS. As a result, we have a good grasp of the technology to detect antibodies in blood. When we received the genetic code for the new SARS-CoV-2 in January, we immediately got to work. With that code you can make the proteins that the immune system must respond to to expel the virus, the so-called spike proteins. You give it a color. You put them in contact with blood and then the SARS-CoV-2 stains specific B cells, which are responsible for making antibodies. We took the genetic material from those B cells to make the antibodies. In this way we have obtained more than eighty antibodies. We put them in contact with the virus to see how efficiently they killed it. The less you need the better. And so we came across two very powerful antibodies. These are now produced in large pots in our laboratory. ”

We are now more than two months after the publication in Science. How is the research progressing?

“We want to get the drug on the market as soon as possible. The first animal tests have now been done and are working out well. We are now looking for a company that can make the drug according to the official pharmaceutical regulations. You want consistent quality in sufficient quantities. For this we are supported by the Bill & Melinda Gates foundation. As soon as there are enough safely produced antibodies, tests in healthy volunteers begin. If they are successful, then we will test the drug in patients: do they get better or less ill more quickly compared to patients who don't get it? You understand, all this takes time. Making antibodies is not complicated, but must be done properly and safely. That is why it is important to use a powerful antibody. Then you need smaller quantities and the medicine, which is administered as an injection or infusion, becomes cheaper. A pill is unfortunately not an option, the antibodies do not survive the stomach.

The coronavirus can mutate. Does a change in the virus influence the effect of the antibodies you have found?

“Mutations are part of viruses. With HIV, it is a problem to find a vaccine because it changes so quickly. This corona virus also mutates, but fortunately a lot less quickly than HIV. There are now - to put it simply - two tribes circulating. A new tribe replaces an old one. The new tribe gradually becomes dominant. We have tested our antibodies on the two prevailing strains and they do equally well in both cases. Mutations are always a problem. That is why you prefer not to give patients one antibody, but a cocktail of two or three different antibodies. ”

Tekst: Marc van den Broek