Hexon-modified recombinant E1-deleted adenovirus vectors as dual specificity vaccine carriers for influenza virus

Mol Ther. 2013 Mar;21(3):696-706. doi: 10.1038/mt.2012.248. Epub 2012 Dec 11.

Abstract

To determine if an ordered and repetitive display of an epitope promoted induction of superior antibody responses, we compared B-cell responses to an influenza A virus epitope that was either encoded as a transgene by an adenovirus (Ad) vector or expressed on the vector's surface. To this end, we constructed a panel of influenza A virus vaccines based on chimpanzee-derived replication-defective adenovirus (AdC) vectors of serotype SAd-V25 also called AdC68. AdC68 vectors were modified to express a linear B-cell epitope of the ectodomain of matrix 2 (M2e) within variable regions 1 (VR1) or 4 (VR4) of the adenovirus hexon. Additional vectors with wild-type or M2e-modified hexon encoded M2e fused to the influenza A virus nucleoprotein (NP) as a transgene product. Hexon-modified vectors were tested for immunogenicity and efficacy in mice in comparison to vectors with native hexon expressing the M2e-NP fusion protein. Upon priming, vectors expressing M2e within VR1 of hexon induced M2e-specific antibody responses of higher magnitude and avidity than those carrying M2e within VR4 or vectors expressing the M2e as part of a transgene product. CD8(+) T-cell responses to the transgenic NP were comparable between vectors. M2e-specific antibody responses could be boosted by a second dose of the VR1 hexon-modified vector but not by repeated immunization with the VR4 hexon-modified vector.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / genetics*
  • Animals
  • CD8-Positive T-Lymphocytes / immunology
  • Epitopes, B-Lymphocyte / immunology
  • Genetic Therapy
  • Genetic Vectors*
  • Influenza A virus / immunology*
  • Influenza Vaccines / genetics*
  • Influenza Vaccines / immunology
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred ICR
  • Nucleocapsid Proteins
  • RNA-Binding Proteins / genetics
  • RNA-Binding Proteins / immunology
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Sensitivity and Specificity
  • Viral Core Proteins / genetics
  • Viral Core Proteins / immunology
  • Viral Matrix Proteins / genetics
  • Viral Matrix Proteins / immunology

Substances

  • Epitopes, B-Lymphocyte
  • Influenza Vaccines
  • M2 protein, Influenza A virus
  • NP protein, Influenza A virus
  • Nucleocapsid Proteins
  • RNA-Binding Proteins
  • Recombinant Fusion Proteins
  • Viral Core Proteins
  • Viral Matrix Proteins