The clinical investigation of OX40/OX40L from lymphocytes of patients with Graves' disease after (131)I therapy

Abstract

Objective To investigate the clinical value and the expression of OX40/OX40L from lymphocytes of patients with Graves' disease (GD) before and after 131I therapy.Methods The expression of OX40/OX40L on T,B lymphocytes and the percentage of lymphocyte subsets were analyzed using immunofluorescence staining and flow cytometry in 32 patients with GD before and after 131I therapy.Twenty-five healthy subjects were considered as the control group.The data between GD patients and controls were compared with two-sample t test.The correlation between the expression of OX40/OX40L and the function of thyroid (FT3,FT4 and TRAb level) was performed with linear correlation analysis.Results Compared with the healthy subjects,the percentage of CD4+ T cells and ratio of CD4+/CD8+ were decreased ((34.36 ±6.73)％ vs (45.60-±5.72)％,t=2.634; 1.24±0.26 vs 1.84±0.37,t=2.125,both P＜0.05).Whereas the percentage of CD19+ B cells in patients with GD were significantly higher than that in healthy subjects ((21.42 ±3.92)％ vs (15.35 ± 3.15)％,t =2.653,P ＜0.05).The expression of OX40 increased in CD4+ T lymphocytes ((12.92 ± 2.26) ％) and OX40L expression was up-regulated in CD19+ B lymphocytes ((15.33 ± 3.75)％) of patients with GD,compared with the healthy subjects ((4.19 ±1.45) ％ and (8.64 ± 1.73) ％,respectively,t =2.112 and 2.467,both P ＜ 0.05).The expression of OX40 in CD4+ T lymphocytes ((7.65 ± 1.64) ％) and OX40L in CD19+ B lymphocytes ((11.50 ±2.72)％) were increased after 131I therapy(t =2.795,2.393,both P ＜0.05).The thyroid functions of 32 GD patients were improved.The levels of FT3,FT4 and TRAb decreased significantly after 131I treatment (from 20.79 ±6.05 to 4.53 ± 2.54,from 49.65 ± 10.12 to 13.69 ± 4.35,and from 24.78 ± 8.46 to 11.74 ±6.19,respectively; t =2.219,2.441 and 2.293,all P＜0.05).The levels of FT3 and FT4 were positively correlated with the percentage of OX40 expression in CD4+ T lymphocytes (r =0.65 and 0.73,both P ＜ 0.05).TRAb was positively correlated with CD19+ OX40L + B lymphocytes (r =0.76,P ＜ 0.05).Conclusions OX40/OX40L may play an important role in the activation of lymphocytes,the production of antibodies,and participate in the pathogenesis and progression of GD.131I therapy not only damages most of the thyroid follicular epithelial cells by its β ray,but also facilitates GD improvement by regulating T and B lymphocyte functions. Key words: Graves' disease; Radiotherapy; Iodine radioisotopes; Lymphocytes ; Tumor necrosis factor; Receptors, tumor necrosis factor