Abstract
Purpose :
Graves’ orbitopathy (GO) is an inflammatory autoimmune disorder caused by antibodies directed against the Thyroid stimulating hormone receptor. Phenotypically, regulatory T cells suppress proliferation of effector cells and CD57+ expression correlates with late immune responses. Recently, it was proposed that the imbalance of these subsets cells is critical to its pathogenesis, and there are no studies in humans that correlate the immune response to the clinical findings in this entity. The purpose of this study was to compare effector T cells (CD8+CD57+CD103+) and regulatory T cells (CD4+CD25+FOXP3+) frequency in patients with active, inactive Graves Orbithopathy and controls, and its correlation with the VISA classification and levels of thyroid antibodies. We performed a prospective, transversal and comparative study.
Methods :
30 patients included. Patients were divided into groups according to the Clinical Activity Score (CAS). CD4+CD57+ T cells, CD8+CD57+ T cells, CD8+CD103+ T cells and CD4+CD25+FOXP3+ cells were quantitated in peripheral blood with immunofluorescence staining by flow cytometry from patients with active and non-active GO, and compared with healthy controls (HC). Thyroglobulin (TG) and thyroid peroxidase (TPO) antibodies in serum were determined in all groups.
Results :
Anti-TG and anti-TPO were significantly increased in patients with inactive GO compare with controls and active GO. CD8+CD103+ cells and CD4+CD25+FOXP3+ T cells showed no significant differences in patients with GO (p>0.05), nor when were compared with HC. CD4+CD57+ T cells (p=0.010) and CD8+CD57+ T cells (p=0.002) were significantly increased in patients with non-active GO. In the correlation with VISA classification was observed that greater the score greater the levels of effector T cells CD57+ and CD8+CD103+. Results were analyzed with U Mann-Whitney and Spearman Test.
Conclusions :
There is a significant difference in the concentrations of effector and regulatory T lymphocytes in patients with and without Graves' disease; likewise these concentrations can be positively correlated with the clinical classification VISA and the levels of thyroid antibodies.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.