Endocrine Abstracts

Introduction: Hashimoto’s thyroiditis (HT) is multifactorial disease. Interaction between cellular and humoral immunity is base of HT’s pathogenesis. HT’s assessment is difficult because the prevalence of patient with an increased titer of thyroid’s autoantibody and normal thyroid’s function is high. Our research focuses on the estimating of the prevalence of HT in certain regions of the Russian Federation (Tula Region and Chechen Republic), and estimating functional activity and the quantity of T regulatory and B regulatory lymphocytes in blood from patients, who have features of HT. A more accurate understanding of role of regulatory cells in the immunotolerance disorders could be a base for the development of new prognostic markers and therapeutic strategies in the treatment of patients with HT.

Main part: The study was conducted in 3 districts of the Tula region (TR) (n = 286), 4 districts of the Chechen Republic (CR) (n = 302). The volume of the study was 588 adult people (over 18 years old). 19.9% participants in the TR, 27.15% in the CR have an elevated titer of AT-TPO in the blood serum. And 19.9% participants in the TR, 21.2% in the CR have ultrasound signs of autoimmune thyroid changes. Prevalence of hypothyroidism due to AIT is 16.4% in the structure of the general thyroid pathology in the TR; there are 13.36% in the CR. We analyzed amount and functional activity subsets of regulatory T and B cells (CD3hiIL-10hi and CD19hiCD38hiCD24hi) in subjects’s blood: patient with isolated hypothyroidism in the outcome of HT (n = 23), carriers of antibodies to thyroid tissues (n = 18), patients with HT as a part of autoimmune polyglandular syndrome (APS) (n = 20), healthy donors (HD) (n = 13). We found significant differences in the amount of regulatory cells (CD19hiCD38hiD24hi B reg) during in vitro incubation without additional activation in groups carriers of antibodies (1.75% vs 3.0%; P = 0.0003) and in groups patients with HT as part of APS (1.5% vs 3.0% P = 0.0002) as compared with HD. A decrease in the induction of regulatory B cells was found only in the group of patients with HT as part of APS (2.3%, P = 0.04)

Conclusion: Our research has shown that carriers of autoantibodies and patients with HT as part of APS have reduced spontaneous activation of regulatory B cells in vitro and the latter has activation-induced induction of regulatory B cells in the comparison with HD. The quantity and induction of IL-10-producing T cells in the compared groups weren’t significantly differ. The study is supported by the Russian Science Foundation, Grant No.22-15-00135