The circulating IL-35 regulatory B cells are associated with thyroid associated opthalmopathy.

Background: Thyroid-associated ophthalmopathy (TAO) is the most common orbital disease in adults, potentially leading to disfigurement and visual impairment. However, the causes of TAO are not fully understood. IL-35B cells are a newly identified regulatory B cells (Bregs) in maintaining immune balance in various autoimmune diseases. Yet, the influence of IL-35Bregs in TAO remains unexplored.

Methods: This study enrolled 36 healthy individuals and 14 TAO patients. We isolated peripheral blood mononuclear cells and stimulated them with IL-35 and CpG for 48 h. Flow cytometry was used to measure the percentages of IL-35Bregs.

Results: The percentage of circulating IL-35Bregs was higher in TAO patients, and this increase correlated positively with disease activity. IL-35 significantly increased the generation of IL-35Bregs in healthy individuals. However, B cells from TAO patients exhibited potential impairment in transitioning into IL-35Breg phenotype under IL-35 stimulation.

Conclusions: Our results suggest a potential role of IL-35Bregs in the development of TAO, opening new avenues for understanding disease mechanisms and developing therapeutic approaches.