Recombinant adeno-associated virus expressing the receptor-binding domain of severe acute respiratory syndrome coronavirus S protein elicits neutralizing antibodies: Implication for developing SARS vaccines

Virology. 2006 Sep 15;353(1):6-16. doi: 10.1016/j.virol.2006.03.049. Epub 2006 Jun 21.

Abstract

Development of an effective vaccine for severe acute respiratory syndrome (SARS) remains to be a priority to prevent possible re-emergence of SARS coronavirus (SARS-CoV). We previously demonstrated that the receptor-binding domain (RBD) of SARS-CoV S protein is a major target of neutralizing antibodies. This suggests that the RBD may serve as an ideal vaccine candidate. Recombinant adeno-associated virus (rAAV) has been proven to be an effective system for gene delivery and vaccine development. In this study, a novel vaccine against SARS-CoV was developed based on the rAAV delivery system. The gene encoding RBD was cloned into a pAAV-IRES-hrGFP plasmid. The immunogenicity induced by the resulting recombinant RBD-rAAV was evaluated in BALB/c mice. The results demonstrated that (1) a single dose of RBD-rAAV vaccination could induce sufficient neutralizing antibody against SARS-CoV infection; (2) two more repeated doses of the vaccination boosted the neutralizing antibody to about 5 times of the level achieved by a single dose of the immunization and (3) the level of the antibody continued to increase for the entire duration of the experiment of 5.5 months. These results suggested that RBD-rAAV is a promising SARS candidate vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / biosynthesis
  • Cell Line
  • Dependovirus / genetics*
  • Dependovirus / metabolism*
  • Female
  • Genetic Vectors
  • HeLa Cells
  • Humans
  • Mice
  • Mice, Inbred BALB C
  • Neutralization Tests
  • Protein Structure, Tertiary
  • Receptors, Virus / metabolism*
  • Recombinant Proteins / metabolism
  • Severe acute respiratory syndrome-related coronavirus / immunology*
  • Viral Vaccines / immunology*

Substances

  • Antibodies, Viral
  • Receptors, Virus
  • Recombinant Proteins
  • Viral Vaccines