Expression Of Regulatory B Cells In Graves’ Disease And Its Correlation With Thyroid Function

Objective:Toxic diffuse goiter,also known as Graves’disease,one of the most common organ specific autoimmune diseases,is the most prevalent cause of clinical hyperthyroidism and is influenced by several environmental,genetic and immunological factors.Regulatory B cells(Breg)are important immunosuppressive lymphocytes that play important roles in different autoimmune diseases.At present,whether Breg levels differ in GD under different conditions and the related influencing factors have not been fully clarified.Therefore,we investigated the expression changes of peripheral blood Breg cells in GD patients with different degrees of disease,and the correlation between Breg levels and thyroid related indexes.Methods:The subjects included 153 GD patients who had peripheral blood Breg detection,and 45 healthy subjects who were age-matched and had peripheral blood Breg cell detection.Collect the age,sex,thyroid function,thyroid autoantibody index,blood routine related index and medical records of the subjects.According to the medical records,thyroid function and thyroid hormone receptor antibody(TRAb)of GD patients,they were divided into abnormal thyroid function group(45 cases),normal thyroid function group(60 cases)and normal TRAb group(48 cases).The expression of CD19~+24~+38~+B lymphocyte subsets in peripheral blood of all subjects was evaluated by flow cytometry.Results:The expression level of CD19~+24~+38~+B cell subgroup in peripheral blood of GD group was lower than that of healthy people,and there were differences in the expression of CD19~+24~+38~+B cell subgroup between GD patients at different stages.Taking all GD patients as samples,FT3,FT4 and TRAb were negatively correlated with CD19~+24~+38~+B cells,with r values of-0.38,-0.18 and-0.40 respectively.GD patients were divided according to thyroid function and autoantibody level.The levels of FT3,FT4 and TRAb in GD patients with abnormal thyroid function were negatively correlated with CD19~+24~+38~+B cells,with r values of-0.27,-0.14 and-0.37,respectively;FT3,TRAb and CD19~+24~+38~+B cells in GD patients with normal thyroid function were negatively correlated,with r values of-0.25 and-0.26respectively;No statistically significant correlation between CD19~+24~+38~+B cells and thyroid function index or thyroid autoantibody level was observed in patients with normal GD with TRAb.Through multiple regression analysis,analyze whether the above nail function indicators and autoantibodies jointly affect the expression of Breg in peripheral blood of patients with GD.After gradually incorporating the relevant confounding factors,FT3 and TRAb are correlated with the changes of Breg.The model incorporating these two indicators can explain 38%of the changes of Breg level in patients with Graves disease.Conclusions:The level of regulatory B cells in peripheral blood of GD patients decreased.Among the thyroid related indicators,FT3 and TRAb are related to the level of regulatory B cells,and TRAb is more closely related to the level of regulatory B cells.