Expression of interleukin-17 and interleukin-22 in supernatant of peripheral blood mononuclear cell and tear in dry eye patient / 中华实验眼科杂志

ABSTRACT

Background T helper cell 17 (Th17),a newly discovered subset of CD4+ T cells,have been found to play an important role in dry eye disease in animal model.Further investigation should be done on the immunopathogenesis of Th17 cells in dry eye patients.Objective This study was to analyze the expression status of interleukin-17 (IL-17) and IL-22 in tear and supernatant of peripheral blood mononuclear cells (PBMCs) of dry eye patients and their correlation with clinical symptom and sign.Methods Twenty Sj(o)gren syndrome (SS)patients,twenty non-Sj(o)gren syndrome (NSS) patients were included in Wuxi Second Hospital from 2010 to 2011,and twenty healthy volunteers were recruited at the same period.All of subjects understood the purpose and procedure of research and written informed consent was obtained form each subject initial of this study.Dry eye symptom questionnairs were self-answered and multiple dry eye disease-related clinical tests,including the breakup time of tear film (BUT),Schirmer Ⅰ test (S Ⅰ t) and corneal fluorescein staining were performed.The periphery blood of 3 ml and tear were collected in all the subjects,and IL-17 and IL-22 levels in supernatant of PBMCs and tear were detected by enzyme-linked immunosorbent assay (ELISA).The correlations between levels of IL-17 and IL-22 with BUT,S Ⅰ t,corneal fluorescein staining and dry eye scores were analyzed.Results The dry eye scores reduced,BUT prolonged,S Ⅰ t increased and corneal fluorescein dye decreased from SS group,NSS group to normal control group,with significant differences among the three groups (dry eye scores:H =40.81,P＜0.01 ; BUT:H =40.15,P＜0.01 ;S Ⅰ t..H=50.07,P＜0.01 ;corneal dye scores:H=40.52,P＜0.01).The concentration of IL-17 in the supernatant of PBMCs in the SS patients,NSS patients and normal controls were (964.92±124.83)ng/L,(718.85± 115.89)ng/L and (341.95±85.08) ng/L,showing a statistically significant difference among them (F=162.95,P＜0.01).The levels of IL-17 in the tear were (440.69±126.09) ng/L,(364.33±126.85) ng/L and (61.16±11.60) ng/L in the SS group,NSS group and normal control group respectively,exhibiting an elevated level in the SS group and NSS group compared with the control group (F=75.27,P＜0.01).In addition,the levels of IL-22 in the supernatant of PBMCs in the SS patients,NSS patients and normal controls were (98.77± 11.27) ng/L,(79.65 ± 11.01) ng/L and (32.78±9.34) ng/L,and those in the tear were (22.22 ± 8.96) ng/L,(14.92 ±4.35) ng/L and (10.47 ± 2.67) ng/L,with significant differences among the three groups (F =206.27,P＜0.01 ;F =19.87,P＜0.01).The significant correlations were found between the IL-17 and IL-22 concentration in the supernatant of PBMCs and tear with corneal fluorescein staining scores and S Ⅰ t.Conclusions The contents of IL-17 and IL-22 in PBMCs and tear upregulate in the SS and NSS patients,indicating that Th17 plays a key role in the immunity mechanism of dry eye.