Enzyme-linked immunosorbent assay for determination of antibodies to xanthine oxidase.
An enzyme-linked immunosorbent assay (ELISA) was developed to detect IgG, IgA and IgM antibodies to xanthine oxidase. The method used xanthine oxidase to coat sample wells on microtitre plates. The anti-xanthine oxidase concentrations were determined by reference to standard curves constructed by coating plates with anti-IgG, anti-IgA and anti-IgM to capture antibodies of different classes in standard human serum. The standard curves for IgG, IgA and IgM had a working range of 0 to about 60 ng/ml, and all results with commercial quality control serum fell within expected ranges. The coefficients of variation (CV) for within-batch precision (n = 30) and between-batch precision (n = 20) for IgG and IgM were about 9% and 12% respectively. The detection limit was 2 ng/ml. The ELISA was applied to assay serum samples of 110 Chinese and 110 European healthy subjects. A positively-skewed distribution in their anti-xanthine oxidase IgG and IgM levels was observed.
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Department of Health Sciences, Hong Kong Polytechnic, Hung Hom, Kowloon.
Lewis
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WH
Chui
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SH
D000906:Antibodies / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D014969:Xanthine Oxidase / Q000276:immunology*
D000906:Antibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D014969:Xanthine Oxidase