They discover that 10% of the most serious coronavirus patients had genetic or immune system alterations

Irene Hartmann

09/25/2020 - 11:34

• Clarín.com

• Society

More than 10% of severe coronavirus patients had

 that

the proper functioning of their

, revealed two investigations published in the prestigious specialized journal

The finding not only opens another chapter in understanding the disease but also sheds light on anticipating specific treatments for patients with certain immunological characteristics.

The researchers of the first paper ("

"), led by Jean-Laurent Casanova, from the Howard Hughes Medical Institute (United States), and Paul Bastard, from the Necker Hospital for Children Sick from Paris (France), they tried to decipher

.

What they found was clear: in certain cases, mainly due to autoimmune deficiencies, 

immune system

that are key to fighting the coronavirus:

(IFN).

This, the experts proved, occurs in

of those infected with severe symptoms by covid-19, mostly 

years

.

A patient with coronavirus in the Evita de Lanús hospital.

Photo Guillermo Rodríguez Adami

The second paper ("

") complements the first.

Several of the same researchers participated, but the leadership was led by Qian Zhang of Rockefeller University in New York.

The work showed that

of covid-19 patients between 17 and 77 years old had

in which the body gave an inadequate response against the virus.

Both studies open a

for the most severe patients, since, as the conclusions of the second study support, it is "suggested that the administration of type I IFN may be of

in selected patients, at least in the early stages. of the course of infection by SARS-CoV-2 ".

As

Jorge Quarleri (researcher at the Institute for Biomedical Research in Retrovirus and AIDS, of the UBA-Conicet)

explained to

, "a large amount of interferons is not necessary to fight the covid. But if we also have a low level of autoantibodies, this low amount of interferons can be diminished and, from there, complicate the evolution and control of the infection ".

As detailed, type I interferons are "soluble mediators with clear antiviral activity", but in people with autoimmune diseases (whether the person knows it or not) "it may happen that the antibodies end up

the possibility that these interferons interact with their receptors in cells. By preventing this action, they do not allow the antiviral state that interferons promote to be generated. "

In fact, Quarleri explained, "in the face of a viral infection, the level of these cytokines - interferons - is not very high. But in these patients, the levels were found to be

."

That is, there is an

exactly opposite to that of other complicated cases of coronavirus, such as patients who suffer from an excessive

reaction

, which leads to the well-known Multisystemic Inflammatory Syndrome.

Male genetics

In the first paper, the researchers examined 987 patients with

covid

and found that more than 10% had their own antibodies that

at the onset of infection.

In some cases, these antibodies were detected in blood samples taken before patients were infected, and in others, they were found in the early stages of infection.

Covid-19, seen through a microscope Photo NIAID-RML via AP

Of the 101 patients with these antibodies against type I interferons, 95 were

, which could suggest the presence of some

 on the

, which favors the appearance of this autoimmune phenomenon more prevalent in them.

In addition, about half of the patients with these antibodies were over 65 years old, while they were only found in 38% of those under that age, so it seems that the frequency of these antibodies

.

The researchers also analyzed the presence of autoantibodies in the general healthy population, and in these cases, only 4 of the 1,227 people tested had this type of antibody.

The second study, much more focused on genetic variations, was made from blood samples from more than 650 patients who had been hospitalized for severe pneumonia due to COVID-19, of which 14% died.

They also included samples from another group of more than 530 asymptomatic or mildly infected patients.

The researchers looked for differences between the two groups, analyzing

known to be important for

using type I interferons.

The results showed that a significant number (3.5%) of people with severe disease had

in these 13 genes, mutations that prevented an adequate response against SARS-CoV2 due to

.

Fine-tune the therapy

"During the last 15 years, mutations in these 13 genes have already been described in specific and exceptionally severe cases of other viral infections such as influenza or herpesvirus encephalitis. What surprised us is the high frequency with which we find these alterations in patients with severe covid-19 ", explained to EFE Roger Colobran, scientist of the Vall d'Hebron Diagnostic Immunology Research Group, who also participated in these investigations.

According to Professor Aurora Pujol, a geneticist at the Bellvitge Biomedical Research Institute (Idibell), "now that one of the

of why some young people develop severe forms of the disease is known, we can fine-tune our therapeutic options, such as

".

According to Pujol, this list of mutations, which could also be relevant in other viruses, is likely to grow as more cases are studied.

"Covid-19 patients with a worse prognosis who do not have any of these alterations may have some previous undiagnosed pathology or other genetic susceptibilities that cause an incorrect immune response," the researcher clarified.