title: Antibody response of patients with severe acute respiratory syndrome (SARS) targets the viral nucleocapsid.
abstract: The recent outbreak of severe acute respiratory syndrome (SARS) provided an opportunity to study the antibody response of infected individuals to the causative virus, SARS coronavirus. We examined serum samples obtained from 46 patients with SARS, 40 patients with non-SARS pneumonia, and 38 healthy individuals, by use of Western blotting (WB), enzyme-linked immunoassay (ELISA), and immunofluorescence assay, using both native and bacterially produced antigens of the virus. We found a highly restricted, immunoglobulin G-dominated antibody response in patients with SARS, directed most frequently (89% by ELISA) and predominantly at the nucleocapsid. Almost all of the subjects without SARS had no antinucleocapsid antibodies. The spike protein was the next most frequently targeted, but only 63% of the patients (by ELISA) responded. Other targets of the response identified by use of WB included antigens of 80 and 60 kDa. Several nonstructural proteins cloned were not antigenic, and the culture-derived nucleocapsid appeared to be specifically degraded.
authors.affiliation: Clinical Immunology Unit, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong, HKSAR, China.
authors.forename: Danny Tze Ming
authors.initials: DT
authors.lastname: Leung
authors.forename: Frankie Chi Hang
authors.initials: FC
authors.lastname: Tam
authors.forename: Chun Hung
authors.initials: CH
authors.lastname: Ma
authors.forename: Paul Kay Sheung
authors.initials: PK
authors.lastname: Chan
authors.forename: Jo Lai Ken
authors.initials: JL
authors.lastname: Cheung
authors.forename: Haitao
authors.initials: H
authors.lastname: Niu
authors.forename: John Siu Lun
authors.initials: JS
authors.lastname: Tam
authors.forename: Pak Leong
authors.initials: PL
authors.lastname: Lim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood*; D000956:Antigens, Viral / Q000276:immunology; D015153:Blotting, Western; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D008875:Middle Aged; D008970:Molecular Weight; D019251:Nucleocapsid / Q000276:immunology*; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology*; D045169:Severe Acute Respiratory Syndrome / Q000276:immunology* / Q000821:virology; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D064370:Spike Glycoprotein, Coronavirus; D014759:Viral Envelope Proteins; C578557:spike glycoprotein, SARS-CoV