A new one – dose vaccine may have a more stable immune response than the standard flu vaccine.
Vaccination with replicable regenerative vectors provides a knowledge of transgene-coded antigens in the context of inflammation, which may lead to a more potent and more stable defense in comparison. to non-reproductive vaccines.
A team, led by Kenta Matsuda, HIV Special Protection Division in Immunoregulation Laboratory, National Institutes of Allergies and Infectious Diseases, NIH, tested a type 4 adenovirus encoding the H5 hemagglutinin influenza virus (Ad4-H5- Vtn). with an oral capsule or through a tonsillar swab or nasal spray to better understand the properties of a replica vaccine that directs this response.
In the study, the researchers measured viral peeling from the nose, mouth, and rectum using a polymerase chain test (PCR) and cultures. They also measured serum antibodies by pseudovirus intravenous injection (PVEI), microneutralization (MN), and hemagglutinin inhibition (HAI).
Different types of vaccines
The study included 28 participants who received the vaccine internally, 10 people who received the vaccine as an oral capsule, and 25 people who received the vaccine as a tonsillar swab. The patient population was male health and non-pregnant women between 18–49 years of age.
Those who received the vaccine intravenously or through the tonsillar swab had significantly higher H5 neutral antibody levels than the group that received the oral vaccine.
The researchers found that DNA ad4-H5-Vtn was extracted from the majority of upper respiratory tract (URT) volunteers for 2-4 weeks. However, cultured from only 60% of participants with an interval of 1 day.
In addition, the Ad4-H5-Vtn vaccine caused an increase in H4-specific CD4 + and CD8 + T cells in the peripheral blood and IgG and IgA in nasal, cervical, and rectal secretions.
The researchers also found that the upper respiratory tract vaccines contained high levels of serum neutralizing antibodies to H5, which remained stable at week 26 of the study, while the duration of viral shedding co. related to the size of antibodies neutralization response at week 26.
Overall, adverse events were moderate, with peak neutralizing titer antibodies associated with frequency or duration of adverse event occurrence. The researchers believe that serum neutralizing antibody titers may be stimulated to very high levels 2-5 years after Ad4-H5-Vtn vaccination with reconstituted H5 vaccine or inactivated H5N1 vaccine.
Hope for the future
“Reproduction of Ad4 delivered to the CRT causes prolonged exposure to antigen, drives systemic immunity and stable mucosal, and is a promising platform for the introduction of immunity against viral surface glycoprotein targets , ”Wrote the authors.
The researchers said that replica vector vaccines are possible because they are able to express viral proteins at higher levels and for longer periods of time.
The researchers also said the vaccine platform could be adapted for use against other viruses, such as HIV and SARS-CoV-2.
The study, “Regenerated influenza vaccine with adenovirus, which causes systemic and mucosal immunity,” was published online in The Journal of Clinical Research.