The anti-time rivalry of researchers to unravel the secrets of this “worrying” mutation of the virus

Will their work quell global panic? Since the discovery of Omigran in South Africa on Thursday, November 25, virologists and biologists around the world have been busy unraveling the mysteries of this variation. “Anxiety” Initially baptized by the World Health Organization (WHO) B.1.1.529, the Omicron variant is of concern to experts because of the high number of mutations that raise concerns about the significant prevalence and low effectiveness of the current Govt-19 vaccine. How are scientists trying to see more clearly about this?

Install the virus profile

According to the researchers, combing through the sequence of the Omigron variant is the first step. Like the genetic identification card, the sequence of these letters determines all the characteristics of this new version of Kovit-19. The Omicron series was placed online by a South African laboratory that identified this variation in the Gisaid database, which is accessible to many researchers around the world.

“Thanks to this sequence, we can determine the profile of mutations and viruses”, Olivier Schwartz, director of the Department of Virus and Immunity at the Institute’s Pastor, summarizes, and he is currently working on bringing together about fifteen researchers in his laboratory.

“This sequence makes it possible to identify where the mutations are located: is it in contact with the ACE2 receptor, is it the entry point of the virus in our body? Escape from the antibodies?”

Olivier Schwartz, director of the virus division at the Institute Pastor

to franceinfo

By comparing the sequence of Omigran with previous variations that have spread across the delta and the planet, scientists have been able to identify about thirty mutations in spike protein that play a key role in the entry of the virus. In the body. Some were of known genres, others were not. Problem: Antibodies produced by the currently used Kovit-19 vaccine target the shape of the spike protein properties of the initial mutation of Kovit-19 identified in Wuhan, and may therefore be less effective against Omigran.

Integrate a portion of the virus

Using Omigran’s genetic identification card, some laboratories can perform tests even without a virus sample on hand. “From sorting, laboratories can integrate genes and reintroduce them into their experimental methods.”, Virologist Etienne DeCroly, CNRS research director, explains to franceinfo.

In a week, the institute pastor will be able to break down the virus and make cells that make the perfect copy of the spike protein present in Omigron. Researchers can develop harmless viruses called lentiviruses that produce this particular protein. “We use it to monitor the reactions of antibodies, for example, to study the effectiveness of vaccines, to mimic the entry of omigran into cells.”, Details Olivier Schwartz.

Note the contacts of the virus

Labs that have access to samples of the Omigron variant taken from patients can go further in testing by making the virus interact with the serum. This fluid, obtained by centrifuging blood samples, is highly concentrated in antibodies, making it ideal for monitoring the body’s reactions to this new variant.

“The first thing researchers will do is look at whether the vaccine or antibodies produced by the body after a Govt-19 infection are effective in preventing omega-3s from entering cells.”, Explains Sandrine Sarrazin, Inserm researcher at the Marseille-Luminy Immunology Center.

Scientists at pharmaceutical labs that make vaccines against Covit-19 describe this expert in particular as Pfizer, Bioentech and Moderna.

Thanks to clinical trials still being conducted on vaccines, laboratories can observe the interaction of new variants with the serum of patients receiving one, two or three doses, thus measuring the effectiveness of antibodies depending on the condition.

Sandrine Sarrazin, researcher at the Marseille-Luminy Immunology Center

to franceinfo

In a similar vein, Pfizer, Bioendech and Moderna will test suitable vaccines for Omigran before embarking on any clinical trials. The first two said Friday “Made several months before they could adjust their vaccine within six weeks and deliver the first dose in 100 days” Whether a variant resistant to the antibodies produced by the current vaccine has been found.

In addition, tests may be performed on animals such as genetically modified mice to bind to the ACE2 receptor, which binds to Sars-CoV-2. Golden Syrian hamsters, which are known to be naturally sensitive to Govit-19, can also be used in vivo experiments when developing mild pathology.

Studying the dynamics of infection

Unfortunately, most studies on the vulnerability of Omicron are based on the statistics of individuals directly affected by this variation. To measure its diffusion, and therefore the ability to change the delta or the dynamics of epidemics, researchers will measure the evolution of the rate of positive screenings associated with Omicron.

“Every positive PCR test recorded on the government site Sidep, if it is subjected to a screening test, allows the detection of three mutations called E484K, E484Q and L452R.”, Explains Florence Débarre, researcher in evolutionary biology at CNRS.