Virus-like particle vaccine induces protective immunity against homologous and heterologous strains of influenza virus

J Virol. 2007 Apr;81(7):3514-24. doi: 10.1128/JVI.02052-06. Epub 2007 Jan 24.

Abstract

Recurrent outbreaks of highly pathogenic avian influenza virus pose the threat of pandemic spread of lethal disease and make it a priority to develop safe and effective vaccines. Influenza virus-like particles (VLPs) have been suggested to be a promising vaccine approach. However, VLP-induced immune responses, and their roles in inducing memory immune responses and cross-protective immunity have not been investigated. In this study, we developed VLPs containing influenza virus A/PR8/34 (H1N1) hemagglutinin (HA) and matrix (M1) proteins and investigated their immunogenicity, long-term cross-protective efficacy, and effects on lung proinflammatory cytokines in mice. Intranasal immunization with VLPs containing HA induced high serum and mucosal antibody titers and neutralizing activity against PR8 and A/WSN/33 (H1N1) viruses. Mice immunized with VLPs containing HA showed little or no proinflammatory lung cytokines and were protected from a lethal challenge with mouse-adapted PR8 or WSN viruses even 5 months postimmunization. Influenza VLPs induced mucosal immunoglobulin G and cellular immune responses, which were reactivated rapidly upon virus challenge. Long-lived antibody-secreting cells were detected in the bone marrow of immunized mice. Immune sera administered intranasally were able to confer 100% protection from a lethal challenge with PR8 or WSN, which provides further evidence that anti-HA antibodies are primarily responsible for preventing infection. Taken together, these results indicate that nonreplicating influenza VLPs represent a promising strategy for the development of a safe and effective vaccine to control the spread of lethal influenza viruses.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antibodies / blood
  • Antibodies / immunology
  • CD4-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Line
  • Cytokines / biosynthesis
  • Female
  • Hemagglutinin Glycoproteins, Influenza Virus / immunology
  • Influenza A Virus, H1N1 Subtype / classification*
  • Influenza A Virus, H1N1 Subtype / immunology*
  • Influenza Vaccines / immunology*
  • Mice
  • Mice, Inbred BALB C
  • Microscopy, Electron, Transmission
  • Orthomyxoviridae Infections / immunology*
  • Orthomyxoviridae Infections / prevention & control*
  • Spodoptera
  • Time Factors
  • Virion / immunology*
  • Virion / ultrastructure

Substances

  • Antibodies
  • Cytokines
  • Hemagglutinin Glycoproteins, Influenza Virus
  • Influenza Vaccines
  • hemagglutinin, human influenza A virus