Autoreactive lymphocytes in thyroid disorders. Quantitation of anti-thyroglobulin antibody formation by a specific haemolytic plaque forming cell (PFC) assay.
Blood mononuclear cells (MNC) from 21 patients with autoimmune thyroiditis were assayed for secretion of immunoglobulins in vitro by a reverse haemolytic plaque forming cell (PFC) assay. An antigen-specific assay was employed to quantify anti-thyroglobulin antibody (TgAb) secreting cells. The sensitivities of the two PFC assays were similar. The antigen specificity of the Tg-PFC assay was demonstrated by the ability of free Tg to inhibit PFC formation. The number of spontaneous TgAb-secreting cells was low (median 3 IgG-Tg-PFC/10(6), range 0-35/10(6)); TgAb activity was found in 3% (range 0-11%) of total IgG-PFC. The number of spontaneous IgG-TgAb-secreting cells correlated positively to TgAb titres in serum. MNC from most patients secreted IgG-TgAb upon polyclonal stimulation in vitro for six days with pokeweed mitogen (52 IgG-Tg-PFC/10(6), range 0-478/10(6)); TgAb activity was found among 2% (range 0-8%) of total IgG-PFC. Again, pokeweed mitogen-induced TgAb secretion correlated positively to TgAb titres in serum. Finally, MNC from most patients secreted TgAb after culture with Tg. The Tg-induced response was about 1/3 of the pokeweed mitogen-induced TgAb response. Tg did not increase the production of total IgG indicating that Tg is not a polyclonal stimulus. Few TgAb-secreting MNC were discovered in euthyroid sex and age-matched control patients.
D000368:Aged; D000921:Antibody-Producing Cells / Q000276:immunology*; D001327:Autoimmune Diseases; D001402:B-Lymphocytes / Q000276:immunology*; D005260:Female; D006462:Hemolytic Plaque Technique; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D008875:Middle Aged; D009000:Monocytes / Q000276:immunology*; D011043:Pokeweed Mitogens / Q000494:pharmacology; D013954:Thyroglobulin / Q000276:immunology*; D013966:Thyroiditis / Q000276:immunology*
D007136:Immunoglobulins; D011043:Pokeweed Mitogens; D013954:Thyroglobulin