Endocrine Abstracts

Graves’ disease (GD) is hyperthyroidism associated with organ-specific autoimmune 14 inflammation. GD occurs more frequently in adults than in children, however, pediatric patients are 15 a therapeutic challenge due to cycles of remissions and relapses requiring constant monitoring at 16 every stage of treatment administered. Dendritic cells (DCs) are considered a link between innate 17 and adaptive immunity. DCs as antigen-presenting cells (APCs) are involved in antigen 18 presentation to T lymphocytes, thereby, initiate shift towards effector cells. In accordance, DCs 19 participates also in the modulation of tolerance to specific antigens. To date, the data on DC role in 20 Graves’ pathological processes are scarce. Therefore, here we evaluated frequencies and role of 21 circulating DCs in GD pediatric patients treated with methimazole. Flow cytometric analysis was 22 implemented to evaluate mDC1, mDC2 and pDC cells and their correlation with clinical GD-related 23 parameters. We found significantly higher levels of DC subsets in patients at admission. 24 Furthermore, methimazole treatment seemed to effectively reduce subsets of DCs which, in 25 addition, were found to differentialy correlate with thyroid function. Our study shed a new light on 26 DCs role in pediatric GD pathomechanism. Further studies are required for mechanistic assessment 27 of DCs exact role in disease progression and influence on thyroid function.