title: Antibody avidity maturation during severe acute respiratory syndrome-associated coronavirus infection.
abstract: The maturation of virus-specific immunoglobulin G avidity during severe acute respiratory syndrome-associated coronavirus infection was examined. The avidity indices were low (mean +/- SD, 30.8% +/- 11.6%) among serum samples collected < or =50 days after fever onset, intermediate (mean +/- SD, 52.1% +/- 14.1%) among samples collected between days 51 and 90, and high (mean +/- SD, 78.1% +/- 8.0%) among samples collected after day 90. Avidity indices of 40% and 55% could be considered as cutoff values for determination of recent (< or =50 days) and past (>65 days) infection, respectively. Measurement of antibody avidity can be used to differentiate primary infection from reexposure and to assess humoral responses to candidate vaccines.
authors.affiliation: Centre for Emerging Infectious Diseases, Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong Special Administrative Region, People's Republic of China. paulkschan@cuhk.edu.hk
authors.forename: Paul K S
authors.initials: PK
authors.lastname: Chan
authors.forename: Pak-Leong
authors.initials: PL
authors.lastname: Lim
authors.forename: Esther Y M
authors.initials: EY
authors.lastname: Liu
authors.forename: Jo L K
authors.initials: JL
authors.lastname: Cheung
authors.forename: Danny T M
authors.initials: DT
authors.lastname: Leung
authors.forename: Joseph J Y
authors.initials: JJ
authors.lastname: Sung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000914:Antibodies, Viral / Q000502:physiology*; D000915:Antibody Affinity / Q000502:physiology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D045473:Severe acute respiratory syndrome-related coronavirus / Q000276:immunology; D045169:Severe Acute Respiratory Syndrome / Q000276:immunology*; D013997:Time Factors
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G