Endocrine Abstracts

Th17 cells represent newly discovered CD4+T cells producing predominantly IL17A cytokines, which are involved in inflammations and autoimmune diseases. Elevated IL17 levels were demonstrated in thyroid autoimmunity and the activity of Graves’ ophthalmopathy. The relationship among IL17A, anti-thyroid antibodies, smoking, and clinical activity score of ophthalmopathy was investigated in hyperthyroid Graves’ disease. One hundred and thirty-eight patients, 62 with Graves’ disease (25 with ophthalmopathy, 33 with hyperthyroidism, and 17 have daily smoking), 38 with Hashimoto’s thyroiditis and 38 healthy controls were investigated. Serum IL17A levels were measured with ELISA; thyroid hormones, anti-thyroid antibodies in a fully automated way, but TSH receptor antibodies with RIA. IL17A serum levels were higher in Graves’ patients than those in Hashimoto’s thyroiditis and controls (5.28±3.8 with or 5.43±3.62 ng/ml without ophthalmopathy vs 3.65±2.22 ng/ml, P<0.04 or P<0.01, respectively, for Hashimoto’s thyroiditis and vs 2.83±0.73 ng/ml, P<0.0001 and 0.004 respectively for controls). Smoking increased IL17A levels in comparison with nonsmoking patients in hyperthyroid Graves’ patients after thyrostatic therapy (2.92±1.44 ng/ml vs 10.46±7.18 ng/ml, P<0.04). TSH receptor antibody positive and hyperthyroid smoking patients showed significantly higher IL17A and TSH receptor antibody levels than those who were nonsmoking (3.59±2.28 ng/ml vs 7.24±5.42 ng/ml, P<0.02 for IL17A and 9.07±9.39 U/l vs 22.52±11.48 U/l, P<0.01 for TSH receptor antibodies). No relevant elevation in IL17A levels was connected to clinical activity score of ophthalmopathy. The results highlight the role of IL17A levels in hyperthyroid Graves’ disease. Smoking can play as an aggravating factor in IL17A and TSH receptor antibody elevation.