Immunogenicity and efficacy of recombinant RSV-F vaccine in a mouse model

Vaccine. 2007 Aug 14;25(33):6211-23. doi: 10.1016/j.vaccine.2007.05.068. Epub 2007 Jun 26.

Abstract

RSV vaccine development has constraints due to safety issues encountered by formalin-inactivated FI-RSV vaccines. A desirable vaccine should induce Th(1) responses and a strong mucosal immunity to provide complete protection from RSV infection. In the present paper, we developed and evaluated a mucosal vaccine against RSV in a mouse model. The antigenic regions corresponding to residues 412-524 of RSV-F protein were amplified by RT-PCR and cloned into a vector containing the ctxA(2)B gene of the cholera toxin. The recombinant protein was expressed in E. coli and properties of the recombinant protein were analyzed by SDS-PAGE, Western blot and G(M1)-ELISA. The purified recombinant protein (rRF-412) was used to immunize BALB/c mice intranasally. The results from our studies show that the rRF-412 immunogen induced mucosal (IgA) and systemic antibody (IgG, IgG1, IgG2a, and IgG2b) responses which neutralized RSV. The IgG1/IgG2a ratios indicated a Th(1)-biased antibody response. The Th(1) (TNF-alpha, IL-12p70, IFN-gamma, IL-2) and Th(2) (IL-10, IL-4 and IL-5) cytokine profiles were analyzed after stimulation of spleen cells from mice immunized with purified RF-412 protein. Similar to the antibody response, we observed that the rRF-412 immunogen induced a mixed Th(1)/Th(2) cytokine immune response with a Th(1)-bias response. Serum antibodies were capable of neutralizing RSV and mice immunized with rRF-412 were significantly protected from live RSV challenge. Our data provides evidence that the rRF-412 immunogen may be a potential mucosal vaccine candidate against RSV.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Disease Models, Animal*
  • Female
  • Gene Expression Regulation, Viral
  • Immunity, Mucosal
  • Lung / virology
  • Mice
  • Mice, Inbred BALB C
  • Recombinant Proteins / immunology*
  • Respiratory Syncytial Virus Infections / immunology*
  • Respiratory Syncytial Virus Infections / prevention & control*
  • Respiratory Syncytial Virus Vaccines / immunology*
  • Respiratory Syncytial Viruses / immunology*
  • Respiratory Syncytial Viruses / metabolism
  • Viral Fusion Proteins / genetics
  • Viral Fusion Proteins / immunology*

Substances

  • Antibodies, Viral
  • Recombinant Proteins
  • Respiratory Syncytial Virus Vaccines
  • Viral Fusion Proteins