Physicians, biologists and pharmacists have long been trying to create a universal vaccine against influenza. To do this is not so easy, because strains of viruses are constantly mutating, and, therefore, without genetics this can not be avoided.
The team, led by Professor Deborah Fuller from the University of Washington School of Medicine, hopes the new study will bring the scientists to create a vaccine that will protect patients against all strains of influenza virus, even if they are genetically change over time.
Only a DNA vaccine is capable of this: unlike conventional drugs that force the entire body to generate an immune response at once, the DNA vaccine inserts the genetic code into cells, orienting them to produce an antigen that will elicit an immune response.
In this case, the antiviral DNA vaccine will cause human cells to produce antigens, and will also enhance the work of antibodies and T cells (immune cells) to fight the pathogen.
Such a DNA vaccine will be the first drug in a completely new line of vaccines, which, as Fuller hopes, will eventually expand. Such funds are simply necessary, and on the front there is just the problem of vaccination against influenza. According to the US Centers for Disease Control and Prevention, only in America this year, the flu has recovered twice as many people as last year.
Laboratory staff Deborah Fuller develop a DNA vaccine using the genetic components of the influenza virus. Researchers choose “conservative” components that do not change over time. If the vaccine will affect them, even in the case of gene drift or other changes in strains, its effect will remain effective, the authors explain.
So far, the first version of the vaccine contains DNA encoding proteins from four different strains of the influenza A virus. These proteins cause a strong immune response to each individual strain. In addition, the vaccine includes DNA encoding a protein that is highly conserved, and as a result, it extends to different strains of the virus.
To increase the power of the immune response, the researchers resorted to a fusion: plasmids (small DNA molecules) of E. coli bacteria (E. coli) and hepatitis B virus virus were added to the vaccine . These components contribute to the production of antigens that cause a strong immune response.
During vaccine tests on macaques, experts found that after three doses the drug began to generate a powerful immune response against each of the four “claimed” strains of influenza. But, more importantly, the cellular response also spread to strains “not specified in the conditions of the problem,” that is, the vaccine turned out to be truly universal. And the protection was 100%.
Fuller explains that the vaccine will be administered to patients through the skin, but not with the help of a conventional syringe, but through a gene gun . Such a device can introduce the substance directly into the skin cells. Further, these cells will start producing antibodies and T cells in the body, which will begin to fight the pathogen.
According to researchers, the benefits of a new type of vaccines are obvious. First, this is a fundamentally different action: the drug helps the body to find infected cells and destroy them more efficiently. Secondly, tests on primates showed that the response of T cells occurred so quickly that the animals simply did not have time to get sick. This effect is observed due to the directed action of the DNA vaccine: first of all, the T cells were sent to the lungs, where the most pathogens accumulate.
In addition, the production of DNA vaccine is relatively inexpensive, and also fast: it takes an average of three months, whereas classical drugs are produced about nine months.
A universal vaccine will also save patients from having to do annual flu shots. And if a new pandemic strain of the virus appears, the DNA vaccine, thanks to its rapid action, can prevent a nationwide epidemic.
The authors also note that by the same principles, it is possible to create more effective vaccines from other viral vaccines – for example, the virus Zika .
However, from the first encouraging results to the moment when the new vaccine will appear in commercial production, it will probably take several more years. Ahead – various tests and improvement of the vaccine.
A more detailed description of the “holy grail” of physicians is contained in an article published in the publication PLOS One.
In the meantime, geneticists have created a special test, which will show whether the patient will be helped by the flu vaccine .