Association of HLA Class I and Class II Genes and Adrenal Steroid 21-Hydroxylase Gene with Subacute (de Quervain’s) and Hashimoto’s Thyroiditis: Evidence for an Altered Negative Feedback in Hashimoto’s Thyroiditis
It is a striking feature of organ-specific autoimmune diseases that they are linked to alleles of class I and class II genes of the MHC gene region ; however, until recently the nature of this association was unclear. The hypothesis was then put forward that the MHC molecules per se play a major role in the immune response. They act as restriction elements when antigen-presenting cell and T cell meet in immune recognition either in a physiological milieu or in an autoimmune state . Direct evidence for this hypothesis was deduced from inappropriate expression of MHC molecules on target tissues of an autoimmune attack, i.e., class II expression on pancreatic beta cells in recent-onset type I diabetes mellitus or class I and class II overexpression on thyroid epithelial cells in Graves’ disease . Presentation of an antigen or an autoantigen is a prerequisite in organ-specific autoimmunity, but also specific recognition by the T-cell receptor supplemented by helper factors is necessary for an immune response . Since organ-specific autoimmune diseases are chronic diseases, it might he speculated that the helper factors (interleukins), which provide a positive feedback, play an important role in the maintenance of chronic inflammation during target organ destruction. Also, negative feedback mechanisms such as T-suppressor circuits may be impaired .
KeywordsCortisol Testosterone Glucocorticoid Thyroxine Thyroiditis
Unable to display preview. Download preview PDF.
- 9.Misakia T, Konishi J, Nakashima T, Ilda Y, Kasagi K, Endo K, Uchiyama T, Kuma K, Torizuka K (1985) Immunohistological phenotyping of thyroid infiltrating lymphocytes in Graves’ disease and Hashimoto’s thyroiditis. Clin Exp Immunol 60:104Google Scholar
- 11.Albert ED, Baur MP, Mayr WR (1984) Histocompatibility testing 1984. Springer, Berlin Heidelberg New YorkGoogle Scholar
- 13.Boehm BO, Rosak C, Boehm TLJ, Kuehnl P, White PC, Schöffling K (1986) Classical and late-onset forms of congenital adrenal hyperplasia caused by 21-OH deficiency reveal different alterations in the C4/21-OH gene region. Mol. Biol Med 3:437Google Scholar