[Immunological reactivity and the HLA system antigens in patients with autoimmune thyroiditis and nodular euthyroid...

Factors of nonspecific resistance, cellular and humoral immunity were investigated before operation in 84 patients with nodular euthyroid goiter and in 50 patients with autoimmune thyroiditis, 50 patients were investigated in the long-term postoperative period. Class I HLA antigens were investigated in 205 patients. Humoral changes of immune homeostasis (hyper-production of antithyroid antibodies, an increase in the level of IgM and IgG against a background of the raised number of peripheral blood B-cells, a decrease in the level of lysozyme), disorder of the cellular factor of immunity (specific sensitization of T-lymphocytes to thyroid antigens, a decrease in the number of T-lymphocytes, especially T-suppressors) were detected in autoimmune thyroiditis. Immunological changes in nodular euthyroid goiter were characterized by T-cell sensitization to thyroid extract and microsomal antigen against a decrease in the total number of T-lymphocytes. In most patients with nodular goiter immunity indices after operation returned to normal whereas in patients with autoimmune thyroiditis they showed no tendency to improvement. These data as well as an increase in the frequency of HLA-A11, HLA-A19 and HLA-B8 were indicative of genetically determined primary nature of immune disorders in autoimmune thyroiditis. It was not typical of nodular euthyroid goiter in which an autoimmune process seemed secondary, occurring in response to damage of thyroid tissue by a growing nodule.