Human immunoglobulin G autoantibodies to the thyrotropin receptor from Epstein-Barr virus-transformed B lymphocytes: characterization by immunoprecipitation with recombinant antigen and biological activity.
The TSH receptor (TSH-R) is the target antigen for disease-related autoantibodies in Graves' disease and primary myxoedema, but the repertoire of the antibodies or the nature of the precise antigenic epitopes is not known. We have immortalized peripheral blood B cells from six different autoimmune thyroid disease patients with Epstein-Barr virus and selected IgG-producing B cells by magnetic selection on anti-IgG-coated beads. Purified recombinant insect cell-derived extracellular region of TSH-R was used to identify the positive wells for expansion in culture. Stable B cell lines (n = 11) were obtained, which after limiting dilution led to two stable B cell clones. B cell lines and clones secreted IgG antibody that were shown to react biochemically with metabolically labeled or in vitro translated, nascent extracellular region of TSH-R, giving strong, confirmatory evidence of the presence of anti-TSH-R antibody. Supernatants from lines contained thyroid-stimulating activity, thyroid-blocking activity (as assessed by inhibition of TSH-mediated cAMP stimulation), or both of these activities. Interestingly, antibodies with stimulating activity were generated from a primary myxoedema patient, and antibodies of blocking specificities were obtained from newly diagnosed thyrotoxic Graves' disease patients. Our results favor a fine balance between stimulating and blocking autoantibody activities in determining the clinical presentation observed in patients with autoimmune thyroid disease patients who have these antibodies present in their serum.
Morgenthaler
N G
NG
Department of Medicine, King's College School of Medicine, London, United Kingdom.
Kim
M R
MR
Tremble
J
J
Huang
G C
GC
Richter
W
W
Gupta
M
M
Scherbaum
W A
WA
McGregor
A M
AM
Banga
J P
JP
D000941:Antigens / Q000276:immunology*; D001323:Autoantibodies / Q000096:biosynthesis* / Q000276:immunology / Q000494:pharmacology; D001402:B-Lymphocytes / Q000276:immunology*; D002460:Cell Line; D002461:Cell Line, Transformed; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D006111:Graves Disease / Q000276:immunology; D004854:Herpesvirus 4, Human; D006801:Humans; D007074:Immunoglobulin G / Q000096:biosynthesis* / Q000276:immunology / Q000494:pharmacology; D018189:Immunomagnetic Separation; D007163:Immunosorbent Techniques; D008297:Male; D011989:Receptors, Thyrotropin / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D013961:Thyroid Gland / Q000276:immunology; D013972:Thyrotropin / Q000494:pharmacology
D000941:Antigens; D001323:Autoantibodies; D007074:Immunoglobulin G; D011989:Receptors, Thyrotropin; D011994:Recombinant Proteins; D013972:Thyrotropin; D000242:Cyclic AMP