SOLUBLE INTERLEUKIN-2 RECEPTOR IN SERA OF PATIENTS WITH GRAVES-DISEASE

Recently, in vitro production of interleukin-2 receptor induced by mit ogens have been shown to be imparied in autoimmune disorders including organo-specific autoimmune diseases. The aim of this study was to inv estigate serum levels of soluble interleukin-2 receptor in 20 untreate d patients with Graves' disease and to follow up their changes in rela tion to clinical picture and TSH-receptor-, anti-thyroglobulin-, anti- microsomal as well as anti-eye muscle antibodies. Soluble interleukin- 2 receptor level was significantly increased in newly-diagnosed Graves ' patients compared to controls (667 +/- 270 vs. 205 +/- 45 U/ml) (P < 0.001). Among the patients sera those with active infiltrative ophtha lmopathy had higher soluble interleukin-2 receptor levels than those w ithout eye symptoms (810 +/- 313 vs. 525 +/- 180 U/ml). Soluble interl eukin-2 receptor level was normalized in Methimazole-treatment-induced remission in the majority of patients except those with ophthalopathy . In five patients the soluble interleukin-2 receptor levels were stud ied after interruption of thyrostatic therapy; an increase was observe d in three patients; thereafter hyperthyrosis relapsed in two cases. F urthermore, a correlation was found between soluble interleukin-2 rece ptor levels and TSH-receptor antibodies, however, the association with other immune parameters examined was not significant. In conclusion, an enhanced level of soluble interleukin-2 receptor was detected in pa tients with untreated Graves' disease. This finding might play a signi ficant role in regulation of impaired cell-mediated immune mechanism a nd has a prognostic value for relapse of autoreactive processes.