The search for a universal flu vaccine has so far been an unattainable goal for the scientific community. Although there were some attempts in the 20th century, it was not until the second decade of the 21st century that researchers began to make progress and a phase one clinical trial began in the United States in the summer of 2022. 100 volunteers for flu shotBPL-1357 has been developed by researchers at the National Institute of Allergy and Infectious Diseases (NIAID).
Thanks to the COVID pandemic, which has led to a huge leap in vaccine technology research, researchers have made a new breakthrough in achieving a universal flu vaccine.
new vaccine “multivalent”, described in an article published in the journal “Science,” uses the same messenger ribonucleic acid (mRNA) technology used in Pfizer and Moderna’s SARS-CoV-2 vaccines. Testing in animal models showed that the vaccine significantly reduced signs of disease and prevented death even when exposed to animals flu strains Different from that used in the manufacture of the vaccine.
This new experimental mRNA-based prototype works against all 20 known influenza virus subtypes, which could one day serve as a general preventive measure against it. future flu pandemicAccording to researchers from the Perelman School of Medicine at the University of Pennsylvania (USA).
“Idea is a vaccine that provides people with a basic level of immune memory against different strains of flu, so that there is much less illness and death when the next flu pandemic hits,” says lead study author Scott Hensley.
Hensley and his lab collaborated with mRNA vaccine pioneer Dr. Drew WeissmanRoberts Family Professor of Vaccine Research and Director of Vaccine Research at Penn Medicine.
Influenza virus causes pandemics from time to time with large number of deaths. The most famous was the influenza pandemic.
From 1918–19, it killed at least a million people worldwide. Influenza virus can spread to birds, pigs, and other animals, and epidemics They may have started when one of these species jumps to humans and acquires mutations that make it better suited to spread among humans. Current flu vaccines are only “seasonal” and protect against strains circulating recently, but are not expected to protect against new pandemic strains.
The strategy now used is based on vaccination using immunogens – a type of antigen that provokes an immune response – against all known influenza subtypes to achieve broad protection.
Vaccines are not expected to provide “sterilizing” immunity that completely prevents viral infections.
Instead, the new study shows that the vaccine elicits a memory immune response that can quickly recover and adapt to new pandemic viral strains, significantly reducing severe illness and death from infection.
“This would be comparable to the first generation SARS-CoV-2 mRNA vaccines, which targeted the original Wuhan strain of the coronavirus,” Hensley explains. “Compared to later variants such as Omicron, these original vaccines did not block viral infections completely, but continue to provide prolonged protection against severe disease and death.”
stanislas nistalVirologist and professor of microbiology at CEU San Pablo University explains Science Media CenterThis is a strategy similar to that used to generate messenger RNA vaccines against SARS-CoV-2, but in which they introduce messenger RNA from 20 versions of the hemagglutinin of influenza viruses A and B to give rise to a Could With the virus likely to infect us. “All of this implies that you could potentially have a universal vaccine that is easier and faster to manufacture that could be very useful in the event of a pandemic caused by a new influenza virus. However they discuss this in the article This vaccine could also be very useful in preventing influenza in animals that may suffer from it, and reduce the risk of zoonoses among animals in a global health context.”
The experimental vaccine, when injected and absorbed by recipient cells, begins making copies of the hemagglutinin protein, a major influenza virus protein, for all twenty influenza hemagglutinin subtypes: H1 to H18 for influenza A virus, and influenza Two more for B virus.
“For a conventional vaccine, it would be very challenging to immunize against all these subtypes, but with mRNA technology it is relatively easy,” Hensley says.
talking to smc Raul Ortiz de Lejarzuprofessor of microbiology, scientific advisor and emeritus director of the National Influenza Center of Valladolid, explains that the innovation of this vaccine is that it “uses several antigens from different subtypes of hemagglutinin (including those present in bats) one or a few Getting into conserved regions of antigens. Previously this was more difficult, but current mRNA vaccine platforms allow the incorporation of multiple mRNAs that will induce multiple different proteins, allowing multiplicity and amplitude of response.
The mRNA vaccine elicited high levels of antibodies, which persisted for four months, and reacted strongly to all 20 influenza subtypes
In mice, the mRNA vaccine elicited high levels of antibodies, which persisted for at least four months, and strongly reacted to all 20 influenza subtypes. In addition, the vaccine seemed relatively unaffected by previous exposure to the flu virus, which can reduce the immune response to conventional flu vaccines. The researchers found that the antibody response in the mice was strong and widespread, regardless of whether or not the animals had been previously exposed to the flu virus.
This is in fact the animal model used which is why the study has several limitations, acknowledges ortiz de lazarzu, The studies, according to SMC Adolfo Garcia-Sastre, director of the Institute for Global Health and Emerging Pathogens at Mount Sinai Hospital in New York, “are very promising and, although they suggest protection against all subtypes of influenza virus, they do not We can be sure about this until clinical trials are done on volunteers.
Ortiz de Lejarazu, sarcastically states, “It’s always very healthy in science”, that “mice and ferrets around the world should be in luck because they already have a universal flu vaccine for them.”
Furthermore, Nistel points out, “the article does not yet present data on the potential advance of this vaccine to the next phase in humans, where not only efficacy must be demonstrated, but also adverse effects, dosage or immunogenicity.” Short and long term.” Word”.
Hensley and his colleagues are currently designing human clinical trials. The researchers anticipate that if these trials are successful, the vaccine could be useful in triggering long-term immune memory against all influenza subtypes in people of all age groups, including young children.
“We think this vaccine can significantly reduce the chance of getting a serious flu infection,” Hensley says.