• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

Nat Commun . An H5N1 clade 2.3.4.4b virus vaccine that elicits cross-protective antibodies against conserved domains of H5 and N1 glycoproteins

tetano

Editor, Senior Moderator
Nat Commun


. 2026 Jan 23.
doi: 10.1038/s41467-026-68457-6. Online ahead of print.
An H5N1 clade 2.3.4.4b virus vaccine that elicits cross-protective antibodies against conserved domains of H5 and N1 glycoproteins

Eduard Puente-Massaguer[SUP] 1 2 [/SUP], Thales Galdino Andrade[SUP] 3 [/SUP], Michael J Scherm[SUP] 1 2 [/SUP], Kirill Vasilev[SUP] 1 2 [/SUP], Hassanein Abozeid[SUP] 4 5 [/SUP], Alesandra J Rodriguez[SUP] 3 [/SUP], Joshua Yueh[SUP] 1 2 [/SUP], Disha Bhavsar[SUP] 1 2 [/SUP], John D Campbell[SUP] 6 [/SUP], Dong Yu[SUP] 6 [/SUP], Richard J Webby[SUP] 7 [/SUP], Yoshihiro Kawaoka[SUP] 4 8 9 10 [/SUP], Gabriele Neumann[SUP] 4 [/SUP], Julianna Han[SUP] 3 [/SUP], Andrew B Ward[SUP] 3 [/SUP], Florian Krammer[SUP] 11 12 13 14 15 [/SUP]


Affiliations
Abstract

The continuous evolution and global spread of highly pathogenic avian influenza (HPAI) H5N1 viruses, particularly clade 2.3.4.4b, pose major challenges for pandemic preparedness. This study evaluates a low-dose inactivated split-virus vaccine derived from H5N1 clade 2.3.4.4b, formulated with an Alum/CpG adjuvant, in a preclinical female mouse model. The vaccine induces strong humoral and cellular immunity, generating high titers of cross-reactive antibodies against diverse H5 hemagglutinin (HA) and across different N1 neuraminidase (NA) glycoproteins. The Alum/CpG adjuvant supports substantial antigen dose sparing and promotes a balanced Th1/Th2 profile. Functional assays show potent virus neutralization, neuraminidase inhibition, and antibody-dependent cellular cytotoxicity, alongside robust antigen-specific CD4[SUP]+[/SUP] and CD8[SUP]+[/SUP] T cell responses, efficient control of lung viral replication, and reduced lung inflammation. Vaccinated mice are fully protected from lethal challenge with both homologous H5N1 clade 2.3.4.4b and heterologous clade 1 viruses, despite low hemagglutination inhibition (HAI) titers. Electron microscopy polyclonal epitope mapping shows serum antibodies recognizing multiple epitopes on homologous HA and NA, with cross-reactivity to conserved epitopes on heterologous proteins, indicating broad recognition. Together, these findings support this vaccine candidate as a promising strategy to provide broad, multifunctional, and durable immunity against current and emerging H5N1 threats.


 
Back
Top Bottom