The interaction of MHC and Gm in liability to autoimmune thyroid disease

In studies on immunogenetic factors in autoimmune thyroid disease, the association among Graves' disease, Hashimoto's disease, HLA and Gm haplotypes was investigated in 37 families in which two or more first degree relatives had Graves' disease. The results showed that two genes linked to HLA and Gm appeared to control susceptibility to Graves' and Hashimoto's disease, respectively, and that the individuals who did not have immunogenetic factors were very unlikely to develop Graves' or Hashimoto's disease. In the second study, the role of HLA-DR antigen expression on thyrocytes was investigated in 18 patients with Graves' disease. It was found that DR-positive thyrocytes increased. DR-positive T-cells (from thyroids and peripheral blood) increased in Graves' disease. Interferon gamma increased DR expression on thyrocytes. The results indicated that these changes may cause a vicious circle to produce and perpetuate autoimmune processes in Graves' disease. Finally, the correlation between thyroids and immunoglobulins was investigated in 11 untreated patients with Graves' disease. Thyroid tissues obtained from untreated patients were incubated in organ culture systems with autologous as well as allogeneic immunoglobulins to observe the release of hormones. The release of hormone was stimulated only by autologous immunoglobulins and it is, therefore, postulated that the role of self-recognition, such as anti-idiotype antibody or anti-MHC antibody is crucial in the pathogenesis of Graves' disease.