A study of human-human hybridomas from patients with autoimmune thyroid disease.
Human-human B-cell hybridomas were established using peripheral blood lymphocytes from patients with autoimmune thyroiditis and Graves' disease. Peripheral mononuclear cells (PMC), with or without mitogen prestimulation, were fused with HGPRT-negative human myeloma cell lines (Gm4672 and GM0462) using 44% polyethylene glycol. Developing hybridomas were screened by enzyme-linked immunosorbent assays (ELISAs) for human IgG and IgM and antibodies to human thyroglobulin (hTg) and microsomal antigen (M-Ag). A 125I-TSH binding inhibition assay was utilized for detecting antibodies to TSH receptor (TSH-R) protein. Hybridoma formation was observed only after prior mitogen stimulation of PMC. The amount of antibody secreted by the human-human hybridomas was highly variable (10 ng-100 micrograms/ml IgG/IgM). Nine and six-tenths percent of the hybrids secreted anti-hTg and 8.4% secreted anti-M-Ag. A 5% cloning efficiency was achieved, with detection of specific thyroid autoantibody secretion in one-third of the clones derived from positive hybridomas. Immunoglobulin secretion decreased with time and long-term stable clones were not achieved. Thyroid monoclonal autoantibodies to hTg, M-Ag, and TSH-R (IgG and IgM) detected during these studies were of a low affinity. In addition, antibodies were identified which exhibited marked specificity crossover between hTg, M-Ag, and nonthyroid antigens, suggesting the presence of recurrent epitopes. Such observations may help explain the multiplicity of thyroid autoantibodies in human thyroid disease and indicate a common defect in immunoregulation. We suggest that cross-reacting epitopes may be important in the derivation of thyroid-specific B-cell clones.
D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D001323:Autoantibodies / Q000276:immunology; D002453:Cell Cycle; D002999:Clone Cells; D006111:Graves Disease / Q000276:immunology*; D006801:Humans; D006825:Hybridomas / Q000276:immunology*; D011989:Receptors, Thyrotropin / Q000276:immunology; D013961:Thyroid Gland / Q000276:immunology; D013967:Thyroiditis, Autoimmune / Q000276:immunology*
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D011989:Receptors, Thyrotropin