Development and evaluation of an enzyme-linked immunosorbent assay for detection of antibodies against the spike protein of SARS-coronavirus.
BACKGROUND
Severe acute respiratory syndrome (SARS) is caused by infection with SARS-associated coronavirus (CoV). Amino acid residues 450-650 of the spike (S) glycoprotein of SARS-CoV (S450-650) contains dominant epitopes for anti-viral antibodies (Abs) in patient sera.


OBJECTIVE
To develop and evaluate an ELISA system for detection of anti-S Abs in patient sera.


METHODS
Express recombinant S450-650 in E. Coli and evaluate the sensitivity and specificity of an ELISA system based on the S450-650 polypeptide.


RESULTS
The S450-650-based ELISA detected IgG Abs in 41 out of 51 serum samples from 22 hospitalized patients with probable SARS, a result closely correlated with that obtained with a virus-based ELISA (r = 0.75, k = 0.8). Differential anti-S IgG responses were observed amongst SARS patients. Some of them produced anti-S Abs early during their infection, while others failed to make IgG Abs against the S450-650 polypeptide. None of the serum samples from 100 healthy blood donors was positive in the S450-650-based assay.


CONCLUSIONS
The S450-650-based ELISA can detect anti-S IgG Abs with high sensitivity and specificity.
Zhao
Jincun
J
Department of Immunology, Peking University Health Science Center, 38 Xueyuan Road, Beijing 100083, PR China.
Wang
Wei
W
Wang
Guang-Fa
GF
Li
Yonghua
Y
Zhuang
Hui
H
Xu
Xiaoyuan
X
Ren
Furong
F
Zhao
Zhendong
Z
Gao
Xiao-Ming
XM
D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology*; D008875:Middle Aged; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D045473:Severe acute respiratory syndrome-related coronavirus; D012680:Sensitivity and Specificity; D045169:Severe Acute Respiratory Syndrome; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*
D000914:Antibodies, Viral; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; C578557:spike glycoprotein, SARS-CoV