Abnormal expression of T regulatory cells in primary Sj(o)gren's syndrome / 中华风湿病学杂志

ABSTRACT

Objective This study was designed to investigate the expression of T regulatory cells (Treg) in the peripheral blood and salivary gland of patients with primary Sj(o)gren's syndrome (pSS).Methods The expression of Treg was measured by flow-cytometry analysis in 23 pSS patients and 15 healthy controls.CD4 positive cells were sorted by immunomagnetic beads,Forkhead box protein P3 (Foxp3) mRNA was extracted,real time polymerase chain reaction (RT-PCR) was used to measure Foxp3 mRNA.For the study of salivary gland,five primary billary cirrhosis (PBC) patients without pSS were selected as the control group,the expression of CD4+T cells and Foxp3+ T cells in salivary gland was examined by immunohistochemistry.The result was analyzed by t test.Results The expression of Treg in the peripheral blood of pSS patients [(5±6)％] was lower than healthy controls [(10±5)％] (t=2.190,P=0.036).There was no significant difference in Foxp3-mRNA expression between pSS patients (0.08±0.05) and controls(0.09±0.03 ) (t=0.695,P＞0.05 ).The expression of CD4+ T cells [ ( 30± 10 )％ ] and Foxp3+ T cells [ ( 10.7±5.8 ) ％ ] in the salivary gland of pSS patients increased significantly when compared with PBC control group [CD4+T (11±6)％ and Foxp3+T(3.2+1.1)％ ] (t=4.072,2.840; P＜0.05).Conclusion For pSS patients,the expression of Treg decreases in the peripheral blood,but Treg increases in the salivary gland.The results of this study suggest that Foxp3plays an important role in the pathogenesis of pSS.