Clinical Significance of Serum TSAb and TSBAb in Children with Autoimmune Thyroid Disease / 天津医药

Objective To study clinical value and significance of thyroid receptor stimulating antibody (TSAb) and thyroid stimulating-blocking antibody (TSBAb) on diagnosis and treatment for children with Graves’disease (GD) and Hashimoto’s thyroiditis (HT). Methods Eighty-eight children with autoimmune thyroid disease (AITD) and treatment time less six months were divided into GD group (n=55) and HT group (n=33). Thirty-eight healthy children were used as control (Normal group). Human serum TSAb ELISA kit and human TSBAb ELISA kit were used to detect the serum TSAb and serum TSBAb in three groups. The serum levels of TSAb and TSBAb were compared between three groups. The correla? tion between TSAb and TSBAb, TSAb/TSBAb and free triiodothyronine three (FT3), free thyroxine (FT4), ultra sensitive thy?roid stimulating hormone (TSH) were analyzed. Results The serum level of TSAb was significantly higher in GD group than that of HT group and Normal group (P0.05). There were no significant correlation between serum TSAb, TSBAb and FT3, FT4, TSH (P>0.05). Conclusion TSAb and TSBAb are related to the pathogenesis of GD and HT in children. TSAb and TSBAb have an important clinical value in the diagnosis and treatment for children with GD and HT.

Clinical study of serum TRAb in 1 085 cases of patients with thyroid disease and normal adults / 中华内分泌代谢杂志

Objective Using recombinant TrxTSHRc protein which contains TSBAb antigen epitope as antigen, an enzyme linked immunosorbent assay (ELISA) was established. The cut-off of positive values of TSH receptor antibody (TRAb) was established. Methods Using recombinant TrxTSHRc protein as antigen, the optimum condition was determined, and the indirect ELISA for detecting TRAb (TRAb-C) in the serum of normal control subjects and thyroid disease patients was established. A total of 1 085 patients and healthy controls were tested for this antibody. Results TRAb-C ELISA mainly detected TSBAb. The A405((-x)±s) value in healthy group was 0. 319±0. 107 with a cut-off value ((-x)±2 s)of 0. 533. The positive rate in thyroid disease patients showed significant deviation, with 66. 01 % in patients with Hashimoto's thyroiditis, 41.68% in newly-diagnosed Graves'disease, 6.98% in simple goiter, 11.1% in subacute thyroiditis, 8.7% in nontoxic thyroid nodular goiter, and 3.2% in thyroid adenoma. Conclusion The TRAb-C ELISA mainly detects TSBAb, which is very valuable for autoimmune thyroid disease, especially for the diagnosis, prognosis and therapy evaluation in Hashimoto' s thyroiditis.

Usefulness of Immunoglobulin Fraction Precipitated with Polyethylene Glycol in Assay for TSH Receptor Antibodies using Chinese Hamster Overy Cells Expressing Human TSH Receptors / 대한내분비학회지

BACKGROUND: Graves' disease and primary myxedema are thought to be caused by the action of TSH receptor autoantibodies(thyroid stimulating antibody; TSAb & thyroid stimulation blocking antibody; TSBAb). Thus, detection of these antibodies is crucial in diagnosis and in follow up of those patients. Recently, a sensitive method using human TSH receptor transfected Chinese Hamster Ovary(CHO) cells has been developed. However, the complexity of IgG purification procedure is considered as a limitation for its clinical application as a routine test. The aim of this study is to determine whether polyethylene glycol(PEG)-precipitated immunogiobuIin fraction could substitute for purified IgG. METHODS: We developed optimal conditions for TSAb and TSBAb assays using crude, PEG precipitated immunoglobulin fraction; and evaluated the correlation of TSAb and TSBAb activities between thase measured using crude immunoglobulin fraction and purified IgG to clarify the usefulness of PEG-precipitated immunoglobulin fraction. TSH receptor expressing wild type CHO cells were used in TSAb and CHO cells expressing chimeric TSH receptor(Mc2; 90-165 amino acid residues were substituted by those of rat LH/CG receptar) were used in TSBAb assay to minimize the possible disturbing effects of TSAb in serum. RESULTS: The optimal serum amount for TSAb and TSBAb assay using PEG-precipitated immunoglobulin fraction were 250mL serum equivalent/well and 50mL serum equivalent/well, respectively. The optimal incubation time for both assays were 2 homs, and aptimal ccrncentration of bTSH for TSBAb assay was 0.1U/L. TSAb activities measured with PEG-precipitated immunoglobulin were significantly correlated with those measured with purified IgG in 26 patients with Graves diseases(r=0.93, p<0.001). Although TSBAb activities measured using PEG-precipitated imrnunoglobulin were conelated with those measured using purified IgG in 20 patients with primary myxedema(r=0.86, p<0.001), the positive rate in TSBAb assay using PEG-precipitated immunoglobulin was lower than that of usmg purified IgG(20% v.s. 65%) because of negative conversion of TSBAb activities in samples with weakly positive TSBAb activities measured using purified IgG. CONCLUSION: PEG-precipitated immunoglobulin fraction could be used instead of purified IgG in TSAb assay using hTSHR-tranasfected wild type CHO cells with equal sensitivity and specificity. This simple and practical TSAb assay using PEG-precipitated immunoglobulin in hTSHR-transfected CHO cells would be useful in clinica1 practiee.

Measurements of Thyroid Stimulation Blocking Antibody Activities by Chinese Hamster Ovary ( CHO ) cells Expressing Human TSH Receptors in Patients with Primary Hypothyroidism / 대한내분비학회지

BACKGROUND: The Chinese hamster ovary cells transfected with human TSH receptor cDNA (hTSHR-CHO), expressing functional human TSH receptors, are known to be more sensitive in detection of thyroid stimulating antibodies than FRTL-5 cells. There has been no report on the usefulness of these cells to measure thyroid stimulation blocking antibody (TSBAb) activity which is frequently found in patients with primary myxedema, METHODS: We established the optimal assay condition of measurement of TSBAb using hTSHR-CHO cells, and simultaneously measured TSBAb activities with FRTL-5 cells and with hTSHR-CHO cells in 49 patients with primary myxedema, compared them with their thyrotropin binding inhibitor immunoglobulin (TBII) activities. RESULTS: 1) hTSHR-CHO cells specifically bound bTSH and were stimulated by bTSH in terms of cyclic AMP generation in a dose dependent manner. 2) Myxedema IgG suppressed TSH-stimulated cAMP production of hTSHR-CHO cells in a dose dependent manner reaching plateau at the concentration of I g/L. Normal pooled IgG has no suppressive action at the concentration of less than 1 g/L, but caused significant suppression at the concentration of greater than 1g/L. 3) TSBAb activities measured by hTSHR-CHO cells in 49 patients with primary myxedema were as follows: Four of 25 TBII-negative cases (16%) and 22 of 24 TBII-positive cases (92%) had TSBAb activities. Most of TSBAb positive patients (95%), especially in TBII positive cases, showed very high activities of more than 90%. 4) TSBAb activities measured by hTSHR-CHO cells and those by FRTL-5 cells were both positive in 24 patients (49%), both negative in 18 patients (37%), and were discrepant in 7 patients (14%). The TSBAb activities measured with hTSHR-CHO cells and those measured with FRTL-5 cells were significantly correlated (r=0.71, p< 0.01). 5) Forty five percent of patients with primary myxedema had all of 3 kinds of activities (TBII, hTSHR-CHO cell TSBAb, FRTL-5 cell TSBAb), 37% of them had none of 3 activities and 18% of them had 1 or 2 kinds of activities only. CONCLUSION: The usefulness of hTSHR-CHO cells in measurements of TSBAb activities were confirmed. The TSBAb activities of most patients with primary myxedema measured by hTSHR-CHO cells were concordant with those measured by FRTL-5 cells. However, a small subset of patients (18%) had discrepant results in assays of TSH receptor antibodies according to the differences in TSH receptors (rat, human and porcine) used in assay. Such discrepancy may be explained by heterogeneity in epitopes for blocking TSH receptor antibodies.

STUDY OF SERUM TRAb IN AUTOIMMUNE THYROID DISEASE WITH ABC- ELISA / 西安交通大学学报(医学版)

In this paper the investigation of using a new method-ABC-ELISA in assay of Autoimmune Thyroid Disease are presented. The sensitivity of ABC-ELISA is compared with that of standard ELISA; Its reliability is proven by the methods of detecting TSAb with FRTL-5. TRAb is detected by ABC-ELISA in 91% of untreated Graves'. TRAb is detected by Standard ELISA in 70% of untreated Graves'. The results of ABC-ELISA in 26 untreated Graves' are equal to that of the method of detecting TSAb with FRTL-5. Therefore, we consider that ABC-ELISA is a sensitive, reproducible, convenient method applicable to clinical practice.