Universal flu vaccine shows 100% effectiveness in animals
Finding a universal vaccine that is effective against all types of viruses that cause influenza is one of the tasks of hundreds of research groups around the world. Efforts so far have not been successful, but in a paper published in the journal Science Translational of Medicine, a team of researchers from Duke University (USA) presents a new way to combat influenza viruses by creating a vaccine that stimulates the immune system to attack the part of the virus’s surface that all of them are less variable.
Thus, targeting a common region of the viruses allowed the vaccine to work well in trials conducted on mice and ferrets, with 100% success.
This, they write in the journal, could lead to the development of flu vaccines that are more protective and less reliant on an annual dose, tailored to that year’s versions of the virus.
Even with vaccines, influenza kills about half a million people worldwide each year.
Influenza strains are named by a short code, such as H5N1, which describes the two surface proteins of each strain. H (sometimes HA) hemagglutinin, a candy-shaped protein that binds to a receptor on a human cell, the first step in the virus entering the cell. N is neuraminidasethe second is a protein that allows the newly created virus to leave the host cell and infect other cells.
“There are five to ten times more hemagglutinin in each viral particle than neuraminidase,” explains Nicholas Heaton, who led the study.
The purpose of vaccines is to train the immune system to respond to parts of the virus designed specifically for the variants of flu that are expected to be most prevalent in the next flu season. The reason we need a new flu vaccine every fall is not because the vaccine wears out, says Heaton, but because the flu virus constantly changes the surface proteins that vaccines target.
The problem with current flu vaccines is that they target an area of the virus that is highly variable, making it difficult to find a universal vaccine. But the new approach targets a different, less volatile region of hemagglutinin.
Each viral particle contains five to ten times more hemagglutinin than neuraminidase.
Nicholas Heaton
Duke University
In laboratory and animal tests, the experimental vaccine caused a stronger immune system response to the stem sections because they were kept constant. This boosted the overall immune response to the vaccine, and in some cases even boosted the antibody response to the core region of the protein.
He The next step was to find a vaccine that produces antibodies for the head. and at the same time for the trunk in case of the wrong choice of vaccine or a pandemic.
After injecting a vaccine with 80,000 hemagglutinin variants in some experiments, 100 percent of the mice avoided illness or death from what should have been a lethal dose of influenza virus.