According to a recent study by researchers in the Institute for Biomedical Sciences at Georgia State University, a new universal flu vaccine protects against influenza B viruses, providing broad defense against many strains and better immune protection.
The hemagglutinin (HA) stalk, a stabilized component of the influenza virus used to make the double-layered protein nanoparticle vaccine, produced broadly reactive immune responses and provided strong and long-lasting cross-immune protection against influenza B virus strains from both lineages. The results are presented in the Biomaterials journal.
Public health is seriously threatened by influenza epidemics, and type B influenza has been linked to several particularly bad flu outbreaks. Influenza B viruses cause around one-fourth of clinical illness cases each year.
During influenza seasons, influenza B viruses are occasionally the predominant circulating strains, as was the case in the 2019–20 U.S. flu season, when influenza B caused more than 50% of the cases.
There are two genetically distinct lineages of influenza B that elicit various immunological reactions. The capacity of circulating strains to evade the immune system or vaccination limits the effectiveness of seasonal flu vaccines, which are made with either one or both lineages of influenza B viruses.
Because the HA head, the changeable part of the influenza virus, changes, these vaccinations are frequently useless. Seasonal influenza vaccines must therefore be regularly updated and modified.
In this study, we generated structure-stabilized HA stalk antigens from influenza B and fabricated double-layered protein nanoparticles as universal influenza B vaccine candidates. We found that layered protein nanoparticles incorporated with structure-stabilized constant antigens have potential as a universal influenza vaccine with improved immune protective potency and breadth.
Dr. Baozhong Wang
A universal influenza vaccine that contains conserved virus components and offers very broad cross-protection against various virus strains is urgently required to get beyond these constraints.
“In this study, we generated structure-stabilized HA stalk antigens from influenza B and fabricated double-layered protein nanoparticles as universal influenza B vaccine candidates,” said Dr. Baozhong Wang, senior author of the study and Distinguished University Professor in the Institute for Biomedical Sciences at Georgia State University.
“We found that layered protein nanoparticles incorporated with structure-stabilized constant antigens have potential as a universal influenza vaccine with improved immune protective potency and breadth.”
Both animals and cell cultures were used to evaluate the nanoparticle vaccination. According to studies done in cell culture, dendritic cells, which are essential for triggering protective immune responses against pathogens, were successfully activated by protein nanoparticles when they were taken up by the cells. The vaccine was found to be highly immunogenic in animals, safe, biocompatible, and biodegradable.
“Our next aim is to combine the influenza A nanoparticles from our previous study with the influenza B nanoparticles we have fabricated and tested here to create a multivalent universal influenza nanoparticle vaccine against both influenza A and B,” Wang said.
Co-authors of the study include Yufeng Song (first author), Wandi Zhu, Ye Wang, Lei Deng, Yao Ma, Chunhong Dong, Gilbert X. Gonzalez, Joo Kim, Lai Wei, Sang-Moo Kang, and Bao-Zhong Wang of the Center for Inflammation, Immunity & Infection in the Institute for Biomedical Sciences at Georgia State. Deng is also affiliated with Hunan University in Changsha, China.
The National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID) provides funding for the study (NIH).
