Circulating mononuclear cells from euthyroid patients with thyroid-associated ophthalmopathy exhibit characteristic...

Area of Science:

• Immunology
• Endocrinology
• Ophthalmology

Background:

• Thyroid-associated ophthalmopathy (TAO) is a complex autoimmune condition linked to Graves' disease.
• TAO involves orbital inflammation and tissue remodeling, with variable severity but a generally predictable course.
• The underlying immune mechanisms driving TAO pathogenesis remain incompletely understood.

Purpose of the Study:

• To investigate the phenotypic profile of peripheral blood mononuclear cells (PBMCs) in euthyroid patients with TAO.
• To identify potential immune cell biomarkers associated with the development and persistence of TAO.

Main Methods:

• Prospective, consecutive analysis of PBMC phenotypes.
• Comparison of marker expression on T cells, B cells, and monocytes between TAO patients and healthy controls.
• Flow cytometry was used to quantify cell populations expressing CD69, CD25, and CXCR4.

Main Results:

• Significantly higher fractions of T cells expressing CD69, CD25, or CXCR4 were observed in TAO patients compared to controls.
• A significantly greater fraction of CD19(+) CD25(+) B cells was found in TAO patients.
• No significant differences in monocyte marker expression were detected between the groups.

Conclusions:

• A distinct phenotypic shift in peripheral blood lymphocytes is associated with TAO.
• These immune cell alterations are durable and persist even after the hyperthyroid phase of Graves' disease.
• The observed lymphocyte phenotype may contribute to the immune-mediated processes underlying orbital inflammation in TAO.