title: Recombinant influenza virus carrying the respiratory syncytial virus (RSV) F85-93 CTL epitope reduces RSV replication in mice.
abstract: Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants worldwide. Despite decades of research, there is still no registered vaccine available for this major pathogen. We investigated the protective efficacy of a recombinant influenza virus, PR8/NA-F(85-93), that carries the RSV CD8(+) T cell epitope F(85-93) in its neuraminidase stalk. F(85-93)-specific cytotoxic T lymphocytes (CTLs) were induced in mice after a single intranasal immunization with PR8/NA-F(85-93) virus, and these CTLs provided a significant reduction in the lung viral load upon a subsequent challenge with RSV. To avoid influenza-induced morbidity, we treated mice with matrix protein 2 (M2e)-specific monoclonal antibodies before PR8/NA-F(85-93) virus infection. Treatment with anti-M2e antibodies reduced the infiltration of immune cells in the lungs upon PR8/NA-F(85-93) infection, whereas the formation of inducible bronchus-associated lymphoid tissue was not affected. Moreover, this treatment prevented body weight loss yet still permitted the induction of RSV F-specific T cell responses and significantly reduced RSV replication upon challenge. These results demonstrate that it is possible to take advantage of the infection-permissive protection of M2e-specific antibodies against influenza A virus to induce heterologous CD8(+) T cell-mediated immunity by an influenza A virus vector expressing the RSV F(85-93) epitope.
authors.affiliation: Department for Molecular Biomedical Research, VIB, Ghent, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: De Baets
authors.forename: Bert
authors.initials: B
authors.lastname: Schepens
authors.forename: Koen
authors.initials: K
authors.lastname: Sedeyn
authors.forename: Michael
authors.initials: M
authors.lastname: Schotsaert
authors.forename: Kenny
authors.initials: K
authors.lastname: Roose
authors.forename: Pieter
authors.initials: P
authors.lastname: Bogaert
authors.forename: Walter
authors.initials: W
authors.lastname: Fiers
authors.forename: Xavier
authors.initials: X
authors.lastname: Saelens
mesh_terms: D000818:Animals; D001835:Body Weight; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology*; D005260:Female; D009980:Influenza A virus / Q000235:genetics*; D008168:Lung / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D009439:Neuraminidase / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D011995:Recombination, Genetic; D018357:Respiratory Syncytial Virus Infections / Q000473:pathology / Q000517:prevention & control / Q000821:virology; D012136:Respiratory Syncytial Viruses / Q000235:genetics* / Q000276:immunology* / Q000502:physiology; D014760:Viral Fusion Proteins / Q000235:genetics / Q000276:immunology*; D014764:Viral Proteins / Q000235:genetics; D014779:Virus Replication
chemical_list: D018984:Epitopes, T-Lymphocyte; C526850:F protein, human respiratory syncytial virus; D011993:Recombinant Fusion Proteins; D014760:Viral Fusion Proteins; D014764:Viral Proteins; C487630:NA protein, influenza A virus; D009439:Neuraminidase