Immunogenicity of SARS inactivated vaccine in BALB/c mice

Immunol Lett. 2004 Sep;95(2):139-43. doi: 10.1016/j.imlet.2004.06.014.

Abstract

Severe acute respiratory syndrome (SARS) is a serious infectious threat to public health. To create a novel trial vaccine and evaluate its potency, we attempted to generate a SARS inactivated vaccine using SARS coronavirus (SARS-CoV) strain F69 treated with formaldehyde and mixed with Al(OH)3. Three doses of the vaccine were used to challenge three groups of BALB/c mice. We found that the mice exhibited specific IgM on day 4 and IgG on day 8. The peak titers of IgG were at day 47 in low-dose group (1:19,200) and high-dose group (1:38,400) whereas in middle-dose group (1:19,200), the peak was at day 40. On day 63, the IgG levels reached a plateau. Neutralization assay demonstrated that the antisera could protect Vero-E6 cells from SARS-CoV's infection. Analysis of the antibody specificity revealed that the mouse antisera contained a mixture of antibodies specifically against the structure proteins of SARS-CoV. Furthermore, the mouse antisera conferred higher amount of antibodies against protein N, polypeptide S4 and S2 than those of proteins M and 3CL. These findings suggest that the inactivated SARS-CoV could preserve its antigenicity and the inactivated vaccine can stimulate mice to produce high levels of antibodies with neutralization activity. Results also suggest that polypeptides originating from protein N or S might be a potential target for the generation of a recombinant SARS vaccine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology
  • Antibody Specificity
  • Antigens, Viral / immunology
  • Immune Sera / immunology
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Kinetics
  • Mice
  • Mice, Inbred BALB C
  • Neutralization Tests
  • Severe Acute Respiratory Syndrome / immunology*
  • Severe Acute Respiratory Syndrome / virology
  • Severe acute respiratory syndrome-related coronavirus / immunology*
  • Vaccines, Inactivated / immunology*
  • Viral Vaccines / immunology*

Substances

  • Antibodies, Viral
  • Antigens, Viral
  • Immune Sera
  • Immunoglobulin G
  • Vaccines, Inactivated
  • Viral Vaccines