Humans would be protected in front of the pandemic flu virus

At least seven people analyzed in a study published in ‘Science Immunology‘They would somehow be protected before a pandemic caused by the Avian flu virus H5. This first -line protection against a prepazed virus suggests that humans would be prepared for our immune system to respond quickly if we are infected by H5 viruses, which could reduce cases of severe disease in the case of a pandemic.

The researchers of the Harvard University (USA) They have analyzed the B lymphocytes of seven healthy people in which no exposure to H5 flu viruses had been documented, such as aviar flu.

And the results are promising: They demonstrate that a group of cells of our immune system – Virgin B Levels – contains cells capable of recognizing this type of virus.

“Research suggests that human beings have antibodies capable of recognizing highly pathogenic avian flu strains, or H5N1, which is causing outbreaks in populations of domestic and wild birds,” the authors write.

The study, which analyzed the B cells of 7 healthy human donors, identified naive antibodies that could recognize the region of the ‘head’ of the specific hemagglutinine of H5, a surface molecule in the influenza viruses, and neutralize the H5N1.

These findings confirm that humans could have antibodies that protect against avian flu viruses with pandemic potential.

After documenting vAryan human cases of aviar flu in 2024The United States reported its first human death related to H5N1 earlier this year.

Although the transmission from person to person has not occurred, some studies have predicted that, with only a few mutations in the hemaglutinine (HA) gene, the H5 virus could evolve to transmit through respiratory drops.

To characterize the human immune response to the H5N1 aviar flu virus, scientists analyzed B cells of seven healthy human donors without known exposure to H5 viruses. They identified virgin B cells that recognized H5N1 and those that were reactively reactivated to H5 and a seasonal variant of H1N1.

Specifically, they explain, the B cells had antibodies directed against the ‘head’ of H5N1, or region of union to the receiver, and against the ‘stem’ or the regions not related to the head of the H1/H5 viruses.

In addition, the work shows that most H5 reactive antibodies also recognized other pathogenic strains related to H5 currently circulating.

And, most interesting, the authors showed that a subset of these tont underpos could neutralize the H5N1 In in vitro tests.

Does that mean that we have protection against avian flu pandemia?

“We have identified antibodies that represent a possible ‘first line’ of defense against a prepaid virus,” write the authors of the study.

In statements a Science Media Center, Adolfo García-SastreDirector of the Global Health Institute and emerging pathogens of the Monte Sinaí Hospital in New York, points out that “the article implies that we are prepared for our immune system to respond quickly if we are infected by H5 viruses, which could reduce the cases of severe disease in the case of a pandemic ».

In this sense, Estanislao Nistal, virologist and professor of microbiology at the CEU San Pablo University, says that «the study is relevant and interesting when identifying in different people the presence of B lymphocytes capable of producing antibodies that block the entry of an H5N1 virus that has not yet produced a pandemic outbreak in humans. It is particularly notable that these people have never been infected with H5N1, but it is still possible to have both these B lymphocytes and the antibodies that can generate in front of the virus, have a defense against the virus without ever seeing it.

However, he adds, “this would most likely not be enough in some people in case of infected.” Infection by a new virus such as H5N1 that had a high capacity for replication and transmission, he adds, “it will require such lymphocytes B to be stimulated to prolve and increase the production of antibodies in a considerably, and thus better prevent an infection or infection reduce the disease that causes and transmission ».

The study, he concludes, “serves as evidence of the potential to stimulate the production of antibodies that can block the virus.”