Background: Autoimmune thyroid disease (AITD) is the most common organ-specific autoimmune disorder. Genetic background, environmental and endogenous factors are play important roles in determining the activation of immune cells or the efficacy of the immunoregulatory pathways. Recently emphasizes the immunosuppressive role of B regulatory cells (phenotype CD19+CD24hiCD27+IL-10+, CD19+IL-10+) in regulation of immune response.
Objective and hypotheses: The aim of the study was to estimate the expression of CD19+CD24hiCD27+IL-10+ and CD19+IL-10+(B10) B cells in patients with Graves disease (GD) (n=24, mean age 14.9 years old), in patients with Hashimotos thyroiditis (HT) (n=22, mean age 15.2 years old) in comparison with sex- and age-matched healthy control subjects (n=20, mean age 15.4 years old).
Method: The expression of the immune cells populations were analysed by the four-color flow cytometry using a FACSCanto II cytometer (BD Biosciences).
Results: In untreated patients with Graves disease and HT we observed a significant decrease of CD19+CD24hiCD27+IL-10+ (P<0.033 for GB and P>0.05 for HT) and CD19+IL-10+ (P<0.0431 for GD and P<0.033 for HT) B lymphocytes in comparison to the healthy controls. The analysis of CD1d+CD5+CD19+CD24+CD27+IL-10+B cells in the peripheral blood revealed comparable percentages of these cells in patients with thyroid autoimmune diseases to the healthy controls. In untreated Graves patients negative correlation between percentage of CD19+IL-10+B cells and serum level of TSI (P<0.01) antibodies was found, while no such correlation were detected in relation to CD19+CD24hiCD27+IL-10+B cells.
Conclusion: We conclude that the reduction number of Breg cells with expression of CD19+CD24hiCD27+IL-10+ and CD19+IL-10+(B10) could be responsible for loses immune tolerance and development of autoimmune process in thyroid disorders.
01 Oct 2015 - 03 Oct 2015