Send to:

Choose Destination
See comment in PubMed Commons below
Vaccine. 2012 Nov 6;30(48):6833-8. doi: 10.1016/j.vaccine.2012.09.013. Epub 2012 Sep 18.

Flagellin-HA vaccines protect ferrets and mice against H5N1 highly pathogenic avian influenza virus (HPAIV) infections.

Author information

  • 1VaxInnate Corporation, 3 Cedar Brook Drive, Cranbury, NJ 08512, USA.


In order to meet the global demand for rapid production of pandemic influenza vaccines, we have developed a recombinant fusion vaccine platform in which the globular head of hemagglutinin (HA) antigen is genetically fused to bacterial flagellin (a TLR5 ligand). These flagellin-HA fusion vaccine candidates elicit highly protective immunity against a lethal challenge with 2009 pandemic H1N1 (Liu, et al. PLoS ONE 2011; 6:e20928) or H5N1 influenza A/Vietnam/1203/04 (A/VN) infections in mice (Song, et al. Vaccine 2009;27:5875-88). Here we provide the first evidence showing that two A/VN vaccine candidates elicited HA-specific IgG, reduced nasal virus shedding, and conferred full protection against a lethal A/VN infection in ferrets. Furthermore, we show that similar flagellin-HA vaccine candidates of two other H5N1 HPAIV are immunogenic and/or efficacious in mice. Vaccines of A/Indonesia/5/05 (A/IN) induced significant HAI titers to homologous and heterologous A/Anhui/1/05 (A/AN) H5N1 viruses. Two subcutaneous immunizations with doses of either 0.3 μg or 3 μg of A/IN candidates resulted in ≥ 2.5 log(10) unit reduction in day 5 lung virus titer and 90-100% protection against a lethal A/IN challenge in mice. Both R3.HA5 IN and R3.2xHA5 IN vaccines elicited robust neutralizing antibody responses that last for at least 9 months and demonstrated a significant anamnestic antibody response upon further booster immunization. Finally, we found that two vaccine candidates of A/AN induced significant HAI titers in mice. Taken together, our recombinant flagellin-HA platform has been successfully used to generate potent H5N1 HPAIV vaccine candidates. These promising preclinical results justify the advancement of these candidates into the clinic.

Copyright © 2012 Elsevier Ltd. All rights reserved.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk