Nose drops against the flu
Researchers from the Institute of Biomedical Sciences The University of Georgia has successfully tested a new intranasal vaccine against influenza viruses on mice. The vaccine is a PEI-HA/CpG nanoparticle. Polyethylenimine PEI is used as a reliable and universal delivery system, it simultaneously carries antigens (hemagglutinin, HA), which induce an immune response in the body, and adjuvants (CpG), which enhance it. Complex immune responses and cross-immunity in vaccinated mice were long-lasting, demonstrating protection against different strains of the influenza virus for six months after immunization.
Seasonal flu vaccines usually cause unstable immune responses that weaken quickly, making the population vulnerable to new strains. Intranasal vaccination is an ideal method of preventing acute respiratory infections, as, among other things, it activates local immune responses of the mucous membrane, preventing infection at the site of virus penetration.
HA is a viral protein that plays a key role in infecting cells in the early stages of the disease. In the HA structure, the head and body are distinguished. Existing flu vaccines form immunity against the HA head, but this area is very variable, which reduces the effectiveness when infected with different strains of the virus. The HA body is more permanent for different strains of influenza viruses.
Protein antigens, which are administered intranasally, usually do not provoke an immune response sufficiently, therefore, to obtain highly effective intranasal vaccines, adjuvants are needed that can enhance immune responses, increasing their effectiveness and spectrum of action.
PEI-HA/CpG nanoparticles have demonstrated good potential as a candidate for a cross-vaccine against influenza viruses. The combination of PEI and CpG promoted a complex of immune responses, which led to active cross-protection. The inclusion of CpG and antigens in the same nanoparticle also enhanced cellular immune responses.
In experiments, no serious side effects were observed in mice, but a deeper assessment of the safety of the new vaccine is needed before clinical trials.
Article C.Dong et al. Polycationic HA/CpG Nanoparticles Induce Cross-Protective Influenza Immunity in Mice is published in the journal ACS Applied Materials & Interfaces.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of Georgia State University: Intranasal Flu Vaccine with Nanoparticles Offers Robust Protection, Researchers FindIntranasal Flu Vaccine with Nanoparticles Offers Robust Protection, Researchers Find.