Th17／CD4^＋CD25^＋调节性T淋巴细胞失衡在儿童原发性肾小球疾病中的作用

The imbalance of Th17/CD4^＋CD25^＋ regulatory T lymphocytes in children with primary glomerular diseases

目的探讨Th17细胞、CD4^＋CD25^＋调节性T淋巴细胞（Treg）及其效应因子在儿童原发性肾小球疾病中的作用。方法外周血：选择贵阳市儿童医院肾脏免疫科2013年12月至2014年12月住院确诊为原发性肾小球疾病的患儿30例为观察组，男20例，女10例；发病年龄1．6—14．0岁[（8．2±3．8）岁]。同时收集贵阳市儿童医院同期健康体检儿童10例为健康对照组，男8例，女2例；年龄（5．9±3．3）岁。肾组织：收集贵阳市儿童医院同期经肾活检确诊为原发性肾小球疾病患儿25例为病例组，男17例，女8例；发病年龄2—14岁[（7．7±3．5）岁]。其中微小病变型肾病（MCNS）10例，系膜增生性肾小球肾炎（MsPGN）9例，局灶节段性肾小球硬化（FSGS）6例。同时收集贵阳市儿童医院儿外科5例行肾积水等手术患儿的正常肾组织（距病变组织5cm以上）为对照组。流式细胞仪检测观察组及健康对照组儿童外周血中Th17、Treg细胞的比例；通过荧光定量PCR检测白细胞介素-17（IL-17）mRNA在肾小球疾病患儿及健康儿童外周血中的表达；并用免疫组织化学sP法分析25例原发性肾小球疾病患儿不同病理类型肾组织中IL-17表达水平。结果1．观察组儿童外周血Th17细胞的比例显著高于健康对照组（t=7．635，P〈0．05），而观察组外周血Treg细胞比例显著低于健康对照组（t=19．920，P〈0．05）。2．观察组和健康对照组IL-17mRNA相对表达水平分别为4．427±2．870和1．095±0．212，观察组IL-17mRNA相对表达水平高于健康对照组（t=3．636，P〈0．05）。3．病例组患儿肾组织病理检测阳性，IL-17可表达在肾小球及肾小管细胞的胞质，对照组肾组织内IL-17基本无表达。对照组、MCNS组、MsPGN组和FsGs组IL-17水平分别为0．134±0．007、0．210±0．016、0．237±0．006和0．284±0．024，组间比较差异有统计学意义（F=99．09，P〈0．05）。结论Th17／Treg细胞失衡在肾脏疾病发病机制中起着重要作用，使Th17／Treg细胞恢复平衡可能是肾脏疾病的一个新的治疗靶点。

Objective To investigate the role of Th17/CD4^＋CD25^＋ regulatory T lymphocytes （Treg） and its effector in children with primary glomerular diseases. Methods Peripheral blood：30 patients with primary glomerular diseases from December 2013 to December 2014 in Department of Nephrology at Guiyang Children＇s Hospital were en- rolled as experimental group,20 male, 10 female ;age：1. 6 -14.0 years old [ （8.2 ± 3.8 ） years old ]. Meanwhile, 10 healthy age - matched children after physical examination in Guiyang Children＇s Hospital were collected as health control group, 8 male and 2 female, with mean age （ 5.9 ± 3.3 ） years old. Renal tissue ： 25 patients with primary glomerular diseases diagnosed through renal biopsy in Guiyang Children＇s Hospital were collected as case group, 17 male,8 fe- male ; age ： 2 - 14 years old [ （7.7 ± 3.5 ） years old ]. Among them, 10 patients with minimal change nephrotic syndrome （MCNS） ,9 patients with mesangial proliferative glomerulonephritis （MsPGN） ,6 patients with focal segmental glomerulosclerosis （FSGS）. In addition, 5 age -matched children of hydronephrosis with normal kidney tissue （more than 5 cm from the lesion） in Department of Surgery in Guiyang Children＇s Hospital were recruited as control group. The circulating frequencies of Tbl7 cells and Treg cells in peripheral blood in experimental group and healthy control group were measured by means of flow cytometry. The mRNA expressions of interleukin - 17 （ IL - 17 ） in peripheral blood of the patients and the healthy children were analyzed using real- time polymerase chain reaction（PCR）. The expressions of IL - 17 in renal tissue of different pathological types were tested with immunohistochemical techniques. Results （ 1 ） Circulating frequency of Thl7 cells in experimental group was higher than those in health control group （ t = 7. 635 ,P 〈 0.05 ）. But the circulating frequency of Treg cells in experimental group were lower than those in the health control group （ t = 19. 920,P 〈 0.05 ）. （2） The mRNA level of IL - 17 in the experimental group were higher than that in the health control group （4.427 ± 2. 870 vs 1. 095± 0. 212, t = 3. 636, P 〈 0.05 ）. （ 3 ） Pathological test of renal tissues in case group was positive,IL - 17 expression in glomerular and renal tubular cell cytoplasm was found,but IL - 17 had no expression in renal tissue in the control group. The expressions of IL- 17 in control group, MCNS group, MsPGN group and FSGS group were 0. 154 ± 0. 007, 0. 210 ± 0. 016, 0. 237± 0. 006 and 0. 284 ±0. 024, and there were significant differences among the groups （ F = 99.09,P 〈 0.05 ）. Conclusions The imbalance of Th17/Treg cell plays an impor- tant role in the pathogenesis of renal disease. To recover the balance of Th17/Treg cells may be a new target in the treatment of kidney disease.