Upregulation of thyroid transcription factor-1 and human leukocyte antigen class I in Hashimoto's disease providing a clinical evidence for possible triggering autoimmune reaction

Objective: An increase in the expression of autoantigens and their presenting molecules human leukocyte antigen (HLA) class I has been demonstrated to be responsible for autoimmune diseases. Thyroid transcription factor-1 (TTF-1 or NKX2-1) synchronously upregulates both HLA class I and thyroid-specific autoantigen, which may be involved in the pathological process of autoimmune thyroiditis. In this study, the expressions and potential role of TTF-1 and HLA class I in Hashimoto's disease (HT) were examined. Patients: In this study, 22 resection specimens clinically and histopathologically confirmed to have Hashimoto's disease and 30 normal thyroid specimens from adjacent tissues of thyroid adenoma were used. Measurement: Western blot, real-time PCR, and immunohistochemistry were performed to assay TTF-1 and HLA class I in the thyrocytes of Hashimoto's disease as well as in the normal thyroid from adjacent tissues of thyroid adenoma. Results: The TTF-1 and HLA class I in Hashimoto's disease were significantly higher than those in the controls. Conclusion: Upregulation of TTF-1 and HLA class I in Hashimoto's disease provide a clinical evidence for possible triggering of autoimmune reaction.