title: Simultaneous assay for three types of thyrotropin receptor antibody activities using FRTL-5 cells in patients with autoimmune thyroid diseases.
abstract: The relationships between the different circulating thyrotropin receptor antibodies (TSH-R-abs) in autoimmune thyroid disease (AITD) are complex. In order to investigate them, we have developed an assay for the simultaneous measurement of three types of TSH-R-abs: TSH-binding inhibiting immunoglobulin (TBII): thyroid-stimulating antibody (TS-ab) and TSH-stimulation blocking antibody (TSB-ab). A large number of patients with Graves' disease (GD)--untreated and treated--Hashimoto's thyroiditis (HT), primary myxedema (PM) and non-immune goiter (NIG) were investigated. In untreated Graves' patients the frequency of positive TS-ab and TBII sera was found to be 90 and 69%, respectively, the presence of TS-ab and/or TBII being detected in 98%. After long-term antithyroid treatment administered to GD patients, the frequency of positivity of both TBII and TS-ab was decreased, whether hyperthyroidism was cured or not. The TSB-ab was detected in the serum of 8% of patients with GD, and the frequency of TSB-ab did not increase following treatment and alteration in thyroid function. No significant correlation was found between TSB-ab and thyroid function in Graves' patients. Besides, we found that all the GD patients presenting positive TSB-ab were also TBII positive. A follow-up study of the three TSH-R-abs was performed in 35 patients with GD during a mean of 14.3 +/- 8.5 months (4-34 months) of antithyroid drug treatment. Ten out of 24 patients (42%) with positive TBII and 16 out of 32 (50%) with positive TS-ab turned from positive to negative during the time of follow-up. Regarding relapse in hyperthyroid GD, we found that TS-ab was positive in 80% and TBII was positive in 40% of the patients with Graves' relapse, indicating that the presence of TS-ab is a better index for relapse prediction in Graves' hyperthyroidism than TBII. The TSB-ab was found with higher frequency in HT and PM than in GD, i.e. 21%, 18% and 8%, respectively., The TSB-ab positivity was correlated significantly with TBII in our patients with AITD when TSB-ab was positive. This new simultaneous assay of the three TSH-R-abs should be very helpful for further investigation of the autoimmune aspects of AITD and it should help us to progress in a better understanding of the pathogeny of the different AITDs.
authors.affiliation: Department of Internal Medicine, University Hospital of Lausanne (CHUV), Switzerland.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: L
authors.initials: L
authors.lastname: Portmann
authors.forename: N
authors.initials: N
authors.lastname: Dénéréaz
authors.forename: T
authors.initials: T
authors.lastname: Lemarchand-Béraud
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D000906:Antibodies / Q000032:analysis* / Q000276:immunology; D002460:Cell Line; D003430:Cross-Sectional Studies; D000242:Cyclic AMP / Q000037:antagonists & inhibitors / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006042:Goiter / Q000453:epidemiology / Q000276:immunology / Q000503:physiopathology; D006111:Graves Disease / Q000453:epidemiology / Q000276:immunology / Q000503:physiopathology; D006801:Humans; D006980:Hyperthyroidism / Q000453:epidemiology / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009230:Myxedema / Q000453:epidemiology / Q000276:immunology / Q000503:physiopathology; D051381:Rats; D011989:Receptors, Thyrotropin / Q000032:analysis / Q000276:immunology* / Q000378:metabolism; D013961:Thyroid Gland / Q000737:chemistry / Q000276:immunology* / Q000473:pathology*; D013967:Thyroiditis, Autoimmune / Q000453:epidemiology / Q000276:immunology* / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology
chemical_list: D000906:Antibodies; D011989:Receptors, Thyrotropin; D000242:Cyclic AMP