Immunogenicity of SARS inactivated vaccine in BALB/c mice.
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.
Xiong
Sheng
S
Biomedical Research & Development Center, Floor 5, Building of Biology, Jinan University, Guangzhou 510630, PR China.
Wang
Yi-Fei
YF
Zhang
Mei-Ying
MY
Liu
Xin-Jian
XJ
Zhang
Chuan-Hai
CH
Liu
Shi-Sheng
SS
Qian
Chui-Wen
CW
Li
Jiu-Xiang
JX
Lu
Jia-Hai
JH
Wan
Zhuo-Yue
ZY
Zheng
Huan-Yin
HY
Yan
Xin-Ge
XG
Meng
Min-Jie
MJ
Fan
Jiang-lin
JL
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D000918:Antibody Specificity; D000956:Antigens, Viral / Q000276:immunology; D007106:Immune Sera / Q000276:immunology; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology*; D045169:Severe Acute Respiratory Syndrome / Q000276:immunology* / Q000821:virology; D015164:Vaccines, Inactivated / Q000276:immunology*; D014765:Viral Vaccines / Q000276:immunology*
D000914:Antibodies, Viral; D000956:Antigens, Viral; D007106:Immune Sera; D007074:Immunoglobulin G; D015164:Vaccines, Inactivated; D014765:Viral Vaccines