title: A supersensitive in-house enzyme-linked immunosorbent assay (ELISA) for measurement of thyroid-stimulating hormone (TSH) and its clinical applications.
abstract: A supersensitive ELISA was developed for measurement of thyroid-stimulating hormone (TSH) concentrations in serum using in-house rabbit polyclonal antisera and a commercial monoclonal antibody. The assay was optimised and validated by recovery, linearity and cross-reactivity experiments and further compared to other available assays and EQAS samples. Good precision was obtained with a working assay range of 0.2 to 100 mIU/L with < 10% coefficient of variation (CV) for both intra and interassay. The assay is highly sensitive and specific with a minimum detectable limit of 0.07 mIU/L and negligible cross-reactivities against LH, FSH, HCG and other pituitary peptides. Good correlations were obtained when compared to Abbott hTSH EIA (r = 0.993; p < 0.001; n = 85) and NETRIA IRMA (r + 0.995; p < 0.001; n = 76). The normal reference range established was 0.4 to 4.0 mIU/L (n = 76). TSH levels in serum of thyrotoxic patients (n = 83) were significantly lower (0.07 to 0.20 mIU/L, p < 0.0001) and completely distinct from normal values thereby obviating the requirement of a TRH-stimulation test. Stability studies showed that coated wells can be stored at 4 degrees C for at least 2 months. This highly sensitive in-house hTSH ELISA which is cheap, stable and readily available is useful for diagnosis and management of patients with various thyroid disorders.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur.
authors.forename: K H
authors.initials: KH
authors.lastname: Goh
authors.forename: M L
authors.initials: ML
authors.lastname: Ng
authors.forename: E T
authors.initials: ET
authors.lastname: Thean
authors.forename: B A
authors.initials: BA
authors.lastname: Khalid
authors.forename: M L
authors.initials: ML
authors.lastname: Goh
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D012680:Sensitivity and Specificity; D013959:Thyroid Diseases / Q000175:diagnosis; D013972:Thyrotropin / Q000097:blood*
chemical_list: D013972:Thyrotropin