Induction of SARS-nucleoprotein-specific immune response by use of DNA vaccine.
Induction of effective cytotoxic T lymphocyte (CTL) and/or a specific antibody against conserved viral proteins may be essential to the development of a safe and effective severe acute respiratory syndrome coronavirus (SARS-Cov) vaccine. DNA vaccination represents a new strategy for induction of humoral and cellular immune response. To determine the ability of SARS-Cov nucleoprotein (N protein) to induce antiviral immunity, in this report, we established a stable C2C12 line expressing SARS-Cov N protein, which was used as a target for specific CTL assay. We also expressed recombinant N proteins in Escherichia coli and prepared N protein-specific polyclonal antibodies. C3H/He mice were immunized with N protein-expressible pcDN-fn vector by intramuscular injections. We found that the DNA vaccination induced both N protein-specific antibody and specific CTL activity to the target. When C3H/He mice were immunized by three separate injections, high antibody titre (1:3200-1:6400, average titre is 1:4580) and high CTL activity (67.4+/-8.4% (E:T = 25:1), 69.6+/-6.7% (E:T = 50:1) and 71.8+/-6.2% (E:T = 100:1)) were observed. In the case of two vaccine injections, CTL activity was also high (56.6+/-12.7% (E:T = 25:1), 57.4+/-11.7% (E:T = 50:1) and 63.0+/-6.3% (E:T = 100:1)) However, antibody titres were much lower (1:200-1:3200, average titre is 1:980). Our results suggest that SARS-Cov nucleocapsid gene might be a candidate gene for SARS DNA vaccination.
Zhu
Min-Sheng
MS
Huadong Research Institute For Medical Biotechnics, 293 Zhong Shan East Road, Nanjing 210002, PR China. mszhu00@yahoo.com
Pan
Ying
Y
Chen
Hua-Qun
HQ
Shen
Yue
Y
Wang
Xiao-Chun
XC
Sun
Yong-Jun
YJ
Tao
Kai-Hua
KH
D000818:Animals; D000906:Antibodies / Q000276:immunology; D005260:Female; D051379:Mice; D009698:Nucleoproteins / Q000276:immunology*; D011817:Rabbits; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology*; D045169:Severe Acute Respiratory Syndrome / Q000276:immunology / Q000517:prevention & control*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D019444:Vaccines, DNA / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology*
D000906:Antibodies; D009698:Nucleoproteins; D019444:Vaccines, DNA; D014764:Viral Proteins