Change of Th1 and Th2 cells in patients with active Mooren's ulcer

Abstract

Background Mooren 's ulcer is an immune-related corneal inflammatory disease,and its pathogenesis remains below understood.Previous studies showed that the imbalance of T helper cell type 1 (Th1) and Th2 cell play important roles in the development of some autoimmune diseases.Thereby the influence of Th1/Th2 cells on the pathogenesis of Mooren's ulcer is being concerned.Objective This study was to investigate the change of Th1 and Th2 subsets in periphery blood of patients with active Mooren's ulcer.Methods Eleven consecutive patients with active Mooren's ulcer and 8 age-and gener-matched healthy controls were included in Zhongshan Ophthalmic Center,Sun Yat-sen University from January 2012 to July 2013 under the approval of Ethic Committee of this hospital and informed consent of each subject.The peripheral blood samples of all the subjects were obtained separately and periphery blood mononuclear cells (PBMCs)were isolated.The percentages of Th1 and Th2 in the PBMCs were assayed by flow cytometer.The relative expressions of T-bet mRNA,GATA-3 mRNA and signal transducer and activator of transcription 5 (Stat5) mRNA in the PBMCs were examined and compared by real-time fluorescence quantitative PCR (RT-qPCR) Results The percentage of Th1 cells in CD4+ T cells and Th1/Th2 value was 0.21％ (0.11％,0.31％) and 8.01 (4.49,12.01) respectively in the Mooren's ulcer group,which were significantly lower than 0.35％ (0.22％,0.71％)and 23.90 (22.49,33.49)in the normal control group,respectively (Z =-2.01,P =0.04 ; Z =-3.06,P =0.00).However,no significant difference was found in the percentage of Th2 between the two groups (Z=-1.98,P＞0.05).The relative expressions of T-bet mRNA and GATA-3 mRNA in PBMCs were significantly lower in the Mooren's ulcer group than those in the normal control group (Z =-3.47,-3.06,both at P=0.00) ;While the relative expression of Stat5 mRNA in PBMCs was insignificant changed between the two groups (Z =-1.05,P =0.33).Conclusions Th1 and Th2 cells are unbalanced in the active Mooren's ulcer patients.In addition,the down-expression of relevant transcription factors in peripheral blood also is seen in these patients.It is inferred that Th1 and Th2 cells may participate in the progress of Mooren's ulcer. Key words: Mooren's ulcer; CD4+ T lymphocyte; Th1 cell; Th2 cell; Flow cytometry; Real-time fluorescence quantitative PCR