IgA肾病患者血清IgA1与系膜细胞共培养上清诱导足细胞凋亡

目的 探讨IgA肾病(IgAN)患者血清IgA1与系膜细胞共培养上清对足细胞凋亡的影响。 方法 用Jacalin 亲和层析柱和Sephacryl S-200 分子筛纯化蛋白。单体IgA1（mIgA1）热聚合为聚合体IgA1（aIgA1）。实验分为患者上清组、健康上清组和对照组，系膜细胞分别与IgAN患者的aIgA1、健康对照的aIgA1和5%胎牛血清共培养，收集上清，与同步化的足细胞作用。流式细胞仪检测细胞凋亡情况。实时定量PCR 检测凋亡相关基因Bcl-2、Bax、Fas和Fas-L表达情况。 结果 患者上清可诱导足细胞凋亡，其凋亡率显著高于健康上清组和对照组[（28.5±5.9）%比（22.5±5.8）%、（20.5±4.5）%， 均P < 0.05]。患者上清可诱导足细胞Fas mRNA 升高，为对照组的1.89倍（P < 0.05）， 而Bcl-2 mRNA下调为对照组的72%（P < 0.05）。患者上清组的AngⅡ和TGF-β1水平均高于健康上清组[（13.2±3.4） ng/L比（8.2±2.3） ng/L，P < 0.05；（15.4±3.4） ng/L比（10.8±3.2） ng/L，P < 0.05]。 结论 IgAN患者血清IgA1与系膜细胞共培养上清可诱导足细胞凋亡，可能参与IgAN的进展。     

IgA肾病中足细胞损伤及其与蛋白尿的关系

目的 观察 IgA肾病（IgAN）患者足细胞损伤的各种表现，探讨其与蛋白尿的关系。 方法 收集35例伴有明显蛋白尿[尿蛋白量（24 h）>1.0 g]的IgAN患者肾活检组织作研究；以8例肾错构瘤患者术后切除肾和肾癌患者术后远离癌旁肾组织为正常对照。免疫组化方法观察肾组织细胞周期调节蛋白（p21、p27）、足细胞结构蛋白（nestin）、足细胞数目 （WT1）。用显微切割方法取出肾小球，通过实时定量PCR方法检测整合素（integrin）β1、nephrin和α辅肌动蛋白4（α-actinin 4）水平。电镜观察足细胞超微结构的改变。根据足细胞数目密度(Nv, n×106/μm3)将35例IgAN患者分为足细胞数目减少组（ Nv<52.49×106/μm3，n = 15）和足细胞数目正常组（Nv≥52.49×106/μm3，n = 20）。随访蛋白尿的转归情况，共18个月。 结果 （1）与正常对照组比较，IgAN患者肾小球内个别足细胞重新表达p21，而足细胞p27的表达明显降低（0.71±0.12比0.91±0.07，P < 0.05）。（2）IgAN患者足细胞nestin 蛋白表达比正常对照显著降低（13.40%±0.04%比 17.60%±0.04%，P < 0.05）；肾小球内integrin-β1 mRNA表达显著升高（12.54±5.20比1.02±0.30，P < 0.05），而nephrin及α-actinin4 mRNA无明显改变。（3）电镜下观察到明显的足突融合和足细胞从基底膜脱落。（4）IgAN患者足细胞数目密度比正常对照组显著减少(161.27±225.92比323.22±138.12，P < 0.05)，且与Lee氏分级相关。（5）足细胞数目密度、integrin-β1 mRNA与肾穿刺当时的尿蛋白量（24 h）呈负相关(r = -0.4483、-0.840, 均P < 0.05)。足细胞数目减少组较足细胞数目正常组的蛋白尿下降程度明显减少（P < 0.05）。 结论 伴蛋白尿的IgAN中存在足细胞的损伤，表现为足细胞周期调节蛋白、结构蛋白的改变，足突的融合及足细胞数目的减少，而足细胞损伤及足细胞数目减少会影响蛋白尿的发生和发展。     

我国IgA肾病临床与病理联系研究近况

IgA肾病是指一组以肾小球系膜区IgA沉积、同时伴系膜细胞增生和系膜基质增多为主要病理改变的原发性肾小球肾炎[1],是目前导致终末期肾病（ESRD）的主要病因之一[2]。我国IgA肾病占原发肾小球疾病的40%～47.2%,且近10年有明显上升的趋势[3]。肾脏免疫病理是诊断IgA肾病的金标准,     

肥胖相关性肾病伴IgA肾病2例临床病理分析

目的：探讨肥胖相关性肾病（ORG）伴IgA肾病的组织形态学特征、诊断、鉴别诊断、治疗及预后。方法：回顾性分析2例ORG伴IgA肾病的临床病理资料,并结合文献进行复习。结果：2例均为成年人,男女各1例,中位年龄35.5岁;以尿检异常为主要症状,体型肥胖,BMI均超正常值。光镜示：肾小球显著肥大,系膜区及系膜旁区沉积物伴一定数量的肾小球硬化。免疫组化显示以IgA沉积为主的系膜区沉积。电镜显示系膜区少量沉积物伴足突融合及微绒毛变性。结论：ORG伴IgA肾病非常罕见,依赖病理形态学和免疫表型,结合患者有肥胖及BMI超标即可确诊。病理学上需与IgA沉积及肾小球硬化相关肾病加以鉴别。ORG伴IgA肾病治疗方法多种,其预后较难预测。     

尿半乳糖缺陷IgA1水平与IgA肾病严重程度的相关性

探讨IgA肾病（IgA nephropathy,IgAN）患者血清及尿液半乳糖缺陷IgA1（galactose-deficient IgA1,Gd-IgA1）水平与临床病理及肠黏膜屏障损伤指标的相关关系。酶联免疫吸附测定法检测血尿Gd-IgA1、炎性因子及肠黏膜屏障损伤指标水平。IgAN组45例,健康对照组25例。结果...     

强直性脊柱炎相关IgA肾病临床病理分析

目的了解强直性脊柱炎（AS）相关IgA肾病的临床病理特点。方法自1997年1月至2006年12月10年间在北京协和医院接受肾活检确诊为IgA肾病的AS患者10例，回顾性分析其临床及病理特点。结果男性9例，女性l例，平均年龄（28．6＋6．8）岁（16～53岁）。4例患者表现为无症状镜下血尿；6例表现反复血尿合并蛋白尿，其中2例有发作性肉眼血尿。平均尿蛋白量（24h）为（1．56±1．53）g（0．02-5．26g）。2例患者有血压升高。所有患者的血肌酐水平均在正常范围。光镜下，8例患者呈轻度系膜细胞增生，IgA肾病Lee氏分级均为Ⅰ或Ⅱ级；另外2例呈中重度系膜增生性改变，IgA肾病Lee氏分级分别为Ⅲ级和Ⅵ级。结论AS相关IgA肾病临床表现为隐匿性肾炎或慢性肾小球肾炎，病理改变以轻度系膜增生为主。     

IgA肾病血瘀证血清蛋白组学的初步研究

目的：应用表面增强激光解吸/电离飞行时间质谱技术（SELDI-TOF-MS技术）检测IgA肾病患者的血清蛋白质指纹图谱,试图寻找IgA肾病血瘀证相关的差异蛋白质,从蛋白质水平探索IgA肾病血瘀证血清的标志物.方法：采集于2011年10月～2013年2月肾内科住院的IgA肾病患者的血液样本共30例（血瘀证14例,非血瘀证16例）,同时采集健康人血液样本15例.研究各组病例血清蛋白质指纹图谱,所有蛋白质质谱采用Biomarker Wizard分析之后用Biomarker Patterns Software软件识别IgA肾病血瘀证特异表达的蛋白质,并建立证候决策模型.结果：（1）IgA肾病血瘀证患者与正常人血清蛋白质指纹图谱数据比较,经分析检测到30个蛋白质峰差异具有统计学意义（P＆lt;0.05）.（2）IgA肾病血瘀证患者与非血瘀证患者血清蛋白质指纹图谱数据比较,经分析检测到42个蛋白质峰差异具有统计学意义（P＆lt;0.05）.（3）IgA肾病血瘀证差异表达蛋白峰的筛选及证候决策模型的建立.经筛选质荷比为1 092.71（低表达）、1 972.32（低表达）、2 687.74（低表达）、3 196.19（高表达）、3 249.02（高表达）、8 567.20（高表达）、8 713.48（高表达）的7个蛋白峰组成的证候决策模型能很好区分IgA肾病血瘀证,该模型的敏感性为92.85%,特异性为93.75%,进一步对决策模型进行盲法验证,此模型对血瘀证的诊断敏感性为85.71%,特异性为81.25%.结论：M/Z为1 092.71、1 972.32、2 687.74、3 196.19、3 249.02、8 567.20、8 713.48的7个蛋白峰可能是区分IgA肾病血瘀证与非血瘀证的血清蛋白标志物.     

半乳糖缺陷型IgA1在IgA肾病中的研究进展

IgA肾病（IgA nephropathy,IgAN）是全球最常见的原发性肾小球肾炎并且可进展至终末期肾病,IgA1分子沉积在肾小球系膜是其区别于其他原发性肾小球肾炎的明显特征。近年来,IgAN在机制研究、基因组学、临床研究等方面取得了不错的进展,并发现半乳糖缺陷型IgA1（galactose deficient-Ig...     

转铁蛋白受体在IgA肾病肾组织中的表达

目的阐明转铁蛋白受体（cD71、TfR）在IgA肾病（IgAN）肾组织中表达的分布特点及其与IgA表达的关系,探讨其在IgAN免疫发病机制中的作用。方法120例肾活检患者根据临床表现和肾活检病理诊断分为原发性IgAN组（原发组）44例、非IgAN性IgA沉积组（继发组）38例、无IgA沉积肾病组（肾病组）38例。用免疫荧光双套色法标记的抗体,在激光共聚焦荧光显微镜下观察四甲基罗丹明（TRITC）标记的CD71和异硫氰荧光素（FITC）标记的IgA在肾组织上的表达。结果CD71的表达强度与IgA的沉积程度相一致。CD71与IgA在原发组肾小球上高表达;在继发组低表达;在对照组微弱表达或不表达。激光共聚焦荧光显微镜下观察到CD71表达与IgA表达呈现共位现象。结论CD71在IgAN患者肾小球呈现高表达,其表达与IgA分子呈现共位状态,提示CD71可能参与了IgAN免疫发病过程。     

调节性及辅助性T细胞在人类IgA肾病中的表达及意义

目的 探讨CD4+CD25high调节性T细胞（Treg）及辅助性T细胞亚群（Th1、Th2）比例失衡在IgA肾病（IgAN）免疫发病机制中的作用。 方法 用流式细胞仪检测IgAN患者外周血Treg及Th1、Th2的比例。以胞内染色技术检测叉头框蛋白3（FOXP3）的表达。Treg及Th1、Th2的比例与IgAN各项临床病理指标的相关性分析采用Spearman或Pearson相关分析法。 结果 IgAN患者外周血中Treg比例明显高于健康人[（2.14±0.82）％比（1.59±0.53）％，P ＜ 0.05]，与血IgA水平呈正相关（r = 0.397，P ＜ 0.05），与eGFR呈负相关（r = -0.376，P ＜ 0.05）。IgAN患者外周血中Th2细胞比例显著高于健康对照组[（2.57±0.72）％比（1.81±1.10）％，P ＜ 0.05]，与血IgA水平呈正相关（r = 0.468，P ＜ 0.05）。IgAN患者Th1/Th2比值显著低于健康对照组（5.75±1.89比12.73±9.79，P ＜ 0.05），但与临床各指标间没有相关性。 结论 IgAN患者体内存在T细胞亚群表达紊乱。Treg在外周血中的增多以及以Th2为优势的Th1/Th2失衡可能在IgAN的发病中起重要作用。     

胡桃夹综合征并发IgA肾病临床分析

目的 了解胡桃夹综合征并发IgA肾病的临床特点及提高其相应诊治水平。 方法 回顾分析14例胡桃夹综合征并发IgA肾病患者（病例组）及同期36例单纯胡桃夹综合征患者（对照组）的临床资料。所有胡桃夹综合征病例均由彩色多普勒超声和磁共振血管成像（MRA）诊断;IgA肾病均由病理证实。记录两组实验室、影像学资料并进行t检验分析。 结果 两组患者性别、年龄、血压差异无统计学意义。病例组Scr值高于对照组[（81.2±21.3） μmol/L比（61.2±11.8） μmol/L,P < 0.01],尿蛋白量较多[（1.1±0.6） g/d比（0.3±0.2） g/d,P < 0.01],血尿更明显（尿红细胞计分2.3±0.9比1.5±1.3,P < 0.05）。彩色多普勒超声显示两组左肾静脉狭窄处及近肾门处血流速度和内径差异无统计学意义;磁共振血管成像提示两组患者肠系膜上动脉与腹主动脉之间的夹角差异无统计学意义。 结论 对持续存在血尿和蛋白尿、异常红细胞比例较高的胡桃夹综合征患者应考虑存在并发慢性肾炎特别是IgA肾病的可能,应及早行肾活检明确诊断。     

Mass spectrometry proves under-O-glycosylation of glomerular IgA1 in IgA nephropathy

BACKGROUND: The IgA1 molecule, which is predominantly deposited in glomeruli in IgA nephropathy (IgAN), is a unique serum glycoprotein because it has O-glycan side chains in its hinge region. Our study was conducted to investigate the O-glycan structure in the glomerular IgA1 in IgAN. METHODS: The IgA1 was separated from 290 renal biopsy specimens of 278 IgAN patients and from four serum IgA1 samples (IgAN, 2; control, 2). The variety of O-glycan glycoform was determined by estimating the precise molecular weights of the IgA1 hinge glycopeptides using matrix-assisted laser desorption ionization time of flight mass spectrometry. RESULTS: The peak distribution of IgA1 hinge glycopeptides clearly shifted to lesser molecular weights in both glomerular and serum IgA1 in IgAN compared with the serum IgA1 of controls. In the five major peaks of IgA1 hinge glycopeptides in each sample, the numbers of carbohydrates composing O-glycans (GalNAc, Gal, and NANA) in the deposited and serum IgA1 in IgAN patients were significantly fewer than those in the serum IgA1 in the control groups. CONCLUSION: The O-glycan side chains in the hinge of the glomerular IgA1 were highly underglycosylated in IgAN. These results indicate that the decreased sialylation and galactosylation of the IgA1 hinge glycopeptides play a crucial role in its glomerular deposition in IgAN.     

代谢综合征对IgA肾病患者病情的影响

目的 观察代谢综合征（MS）对IgA肾病（IgAN）患者病情的影响。 方法 从确诊为IgAN的病例中,以并发MS的118例作为IgAN-MS组;另从同年龄范围的IgAN病例中随机抽取118例无并发MS者作为IgAN-非MS组,对比分析两组患者的临床病理资料。 结果 IgAN-MS组的尿蛋白量、Scr、体质量指数、平均动脉压、血三酰甘油、空腹血糖及血尿酸水平均显著高于IgAN-非MS组（P ＜ 0.05或P ＜ 0.01）;血高密度脂蛋白（HDL-C）水平显著低于IgAN-非MS组（P ＜ 0.01）;高血压、糖代谢异常及脂代谢异常患者的百分率也显著高于IgAN-非MS组（P ＜ 0.01）。IgAN-MS组的病理改变显著重于IgAN-非MS组（P ＜ 0.01）。Spearman相关分析显示MS与尿蛋白量、Scr、肾小球损伤指数及肾小管间质损伤指数均呈正相关（P ＜ 0.01）。 结论 MS是IgAN进展的一个危险因素。     

An increased polymeric IgA level is not a prognostic marker for progressive IgA nephropathy.

BACKGROUND: Elution of IgA from renal biopsies of patients with primary IgA nephropathy (IgAN) has suggested that mesangial IgA deposits are mainly multimeric in nature. This macromolecular IgA consists of dimeric and polymeric IgA and may be derived from the circulation. In children with IgAN, circulating macromolecular IgA levels correlate with bouts of macroscopic haematuria, but in adults a correlation with disease activity is less clear. Therefore, we have designed a novel method to assess the levels of polymeric IgA (pIgA) in sera from patients and controls. METHODS: A novel precipitation assay using recombinant CD89 was developed to measure pIgA. Polymeric IgA levels were measured in serum samples obtained from healthy volunteers (n = 21) and patients with IgAN (n = 51). Subsequently, serum pIgA levels were correlated with clinical parameters of disease. RESULTS: Serum pIgA levels were significantly increased in patients with IgAN. However, pIgA concentrations relative to total IgA were significantly lower in sera of patients with IgAN. No correlation was found between serum pIgA levels and clinical parameters of IgAN, such as decline of glomerular filtration rate, haematuria or proteinuria. CONCLUSIONS: Although absolute levels of serum pIgA are increased in patients with IgAN as compared with controls, levels of pIgA relative to total serum IgA are lower. No significant correlation was found between serum concentrations of pIgA and clinical parameters of disease. These data support the notion that it is not the size alone, but the physicochemical composition of the macromolecular IgA that is the key factor leading to mesangial deposition.     

Determination of plasma antiglycan autoantibodies in patients with IgA nephropathy and the correlation with clinical characteristics

Objective To establish the measurement of IgA1 O-glycan-specific antiglycan autoantibodies in patients with IgA nephropathy (IgAN), and evaluate their role in the development and progression of IgAN. Methods In the IgAN regular follow-up cohort of Peking University Institute of Nephrology from January 2006 to December 2015, 170 patients drawn by stratified randomization were enrolled in this study. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of plasma galactose-deficient IgA1 (Gd-IgA1) and antiglycan autoantibody (IgG and IgA1). The correlation between antiglycan autoantibodies and clinicopathological parameters was analyzed by linear correlation and multiple linear regression analysis. The receiver operating characteristic curve (ROC) was used to evaluate the value of plasma anti glycide antibodies in the diagnosis of IgAN. Results IgG and IgA1 antiglycan autoantibodies that specifically recognized Fab-hinge region (Fab-HR) antigens could be detected in both IgAN and healthy control group. Agglutinin inhibition test showed that the specific antigen epitope was N-acetylgalactosamine (GalNAc) residue exposed to galactose deficiency in IgA1 hinged region. There was no significant difference in the absolute levels of plasma IgG antiglycan autoantibodies between IgAN and healthy controls (P=0.963). After adjustment of the plasma level of IgG, the normalized antiglycan autoantibody (ln[IgG antiglycan antibody/IgG]) in patients with IgAN was significantly higher than that in healthy controls (0.58±0.31 vs 0.37±0.11, P﹤0.01). The normalized level of IgG antiglycan autoantibody in IgAN patients was positively correlated with 24 h urine protein level during renal biopsy (Spearman r=0.183, P﹤0.05), and was also significantly correlated with 24 h urinary protein level after adjusting for baseline clinical and pathological factors (β=0.713, 95%CI 0.323-1.102, P﹤0.01). The area under ROC curve (AUC) of normalized IgG antiglycan autoantibody in the diagnosis of IgAN was 0.764 (95% CI 0.682-0.845, P﹤0.05). Using the cut-off value of 0.396, the sensitivity and specificity of normalized IgG antiglycan autoantibody for IgAN were 0.729 and 0.700 respectively. There was no significant difference in the absolute or normalized levels of IgA1 antiglycan autoantibodies between IgAN patients and healthy controls. Conclusions Gd-IgA1-specific antiglycan autoantibodies can be detected both in IgAN patients and healthy controls. They are elevated in some patients with IgAN and possibly involved in the development of IgAN.     

进展性IgA肾病患者血清IL-18水平及来氟米特对其的影响

目的：观察进展性IgAN患者的血清白细胞介素-18（IL-18）水平,及来氟米特（LEF）治疗前后对其的影响。方法：将进展性IgAN患者随机分为来氟米特（LEF）组和激素组,使用酶联免疫吸附法（ELISA）检测其治疗前后的血清IL-18水平。结果：共36例患者完成为期12个月的随访,来氟米特联合激素治疗后可使蛋白尿水平显著降低,肾功能维持稳定。患者治疗前血清IL-18水平较对照组显著升高[（360.3±25.2）vs（51.2±8.9）ng/L,P〈0.01],治疗显效者其水平显著降低。Logistic回归显示治疗前血清IL-18水平是预测进展性IgAN患者疗效的独立危险因素（β=-0.582,P=0.001）。结论：来氟米特可作为进展性IgA肾病的有效治疗方案,治疗前IL-18可能成为IgAN发病预测、疗效预判的一个无创指标。     

The disease characteristics of patients both with IgA nephropathy and diabetes mellitus

Objective To sum up and analyze the clinical and pathological characteristics in patients with both IgA nephropathy (IgAN) and diabetes mellitus. Methods A total of 500 patients were recruited, including 25 patients with both IgAN and diabetes mellitus, and 475 patients with IgAN only, who were diagnosed by renal-biopsy during Jan 2015 to Jan 2017 at the First Affiliated Hospital of Zhengzhou University. The clinical and pathological data were collected and analyzed using SPSS 22.0. Propensity Score Matching was used to match and select the patients in the both groups, and thereafter the depth of the basement membrane from the matched patients were compared using electron microscopy. The data of the patients whose follow-up time was ≥3 months were retrospectively collected, and Kaplan-Meier analysis was used to compare the difference of the prognosis. Results Compared to the patients with IgAN only, patients with both IgAN and diabetes mellitus were older [(46.36±13.49) years vs (34.00±13.80) years, P＜0.001], had higher level of serum triglyceride [2.06(1.52, 3.11) mmol/L vs 1.51(1.01, 2.25) mmol/L, P=0.012] and thicker basement membrane [(384.33±61.20) nm vs (346.72±52.65) nm, P=0.044]. The patients with both IgAN and diabetes mellitus were more prone to reach the composite endpoint [4/7(57.14%) vs 25/265(9.33%), P＜0.001] and had worse prognosis (Log-Rank test, P=0.004). Conclusions IgAN patients with diabetes mellitus have different clinical, pathological characteristics and prognosis from patients with IgAN alone. These patients need to be closely monitored and actively treated.     

Clinicopathological features and renal outcomes of IgA nephropathy with acute tubulointerstitial nephropathy

Objective To evaluate the clinicopathological characteristics and outcomes of IgA nephropathy (IgAN) with acute tubulointerstitial nephropathy (ATIN). Methods Patients who were diagnosed as IgAN with ATIN and IgAN without ATIN by renal biopsy in Peking University First Hospital were enrolled. There were 74 cases of IgAN with ATIN, and seventy-four cases of IgAN without ATIN were enrolled based on stratified sampling (chosen by 1∶1). The two groups were well matched with age, gender, follow-up time, mesangial hypercellularity(M), endocapillaryhypercellularity(E), segmental glomerulosclerosis(S), tubular atrophy/interstitial fibrosis(T) and cellular/fibrocellular crescent(C). The clinicopathological characteristics and outcomes of two groups were retrospectively analyzed. A composite end point, defined as 30% or 50% estimated glomerular filtration rate (eGFR) decline and end stage renal disease (ESRD) was used. Renal function and proteinuria during follow-up were observed. Renal survival was calculated by Kaplan-Meier survival analysis and risk factors of progression were analyzed by using univariate and multivariate Cox regression models. Results Seventy-four cases of IgAN with ATIN and seventy-four cases of IgAN without ATIN were enrolled. Serum creatinine [(185.6±83.2) μmol/L vs (146.3±69.2) μmol/L, P=0.010] and incidence of acute kidney disease (AKD) (31.1% vs 5.4%, P＜0.001) were higher in IgAN with ATIN group than those in IgAN without ATIN group. Patients in ATIN group received more immunosuppressive treatment (86.5% vs 58.1%, P＜0.001). During 1 year after biopsy, mean eGFR increased significantly in IgAN with ATIN group [(39.7±14.6) ml?min-1?(1.73 m2)-1 vs (47.2±19.9) ml?min-1?(1.73 m2)-1, P=0.017], but mean eGFR was not statistic different in IgAN without ATIN group [(60.0±30.5) ml?min-1?(1.73 m2)-1 vs (59.0±31.7) ml?min-1?(1.73 m2)-1, P=0.567]. Median follow-up was 23.0 months in IgAN with ATIN group, and Median follow-up was 30.0 months in IgAN without ATIN group. Incidence of composite end point had no significant differences between two groups. IgAN with ATIN was not the independent risk factor for end point. IgAN patients with ATIN were divided into two groups (with AKD and without AKD), then renal survival rate was higher (Log-rank test, χ2=5.293, P=0.021) and the risk for composite end point decreased by 79.2% (HR=0.208, 95%CI 0.046-0.939, P=0.041) in the group with AKD. Conclusions In IgAN, there is a subgroup of patients with the specific pathological phenotype combined with ATIN. Compared with those without AKD, the risk for composite end point of IgAN patients with ATIN and AKD showed a 79.2% decrease.     

肾小管肝型脂肪酸结合蛋白对小鼠IgA肾病的肾脏保护作用

Objective To investigate the renoprotection of tubular L-FABP in murine IgA nephropathy (IgAN） induced by bone marrow transplantation(BMT). Methods IgAN models were reconstituted by BMT from IgAN-prone mice into mice (Tg) transgenically tubular overexpressing human L-FABP (hL-FABP) and wild type (WT) mice. These recipients were sacrificed at 6 and 12 weeks after BMT and their kidneys were collected. The expressions of hL-FABP, fibronectin (FN) and monocyte chemoattractant protein-1(MCP-1) mRNA were detected by real-time PCR. hL-FABP, FN, type Ⅳ collagen (Col Ⅳ), hemeoxygenase-1(HO-1) and 4-hydroxy-2-nonenal (4-HNE) modified proteins were detected by Western blotting. The distribution of hL-FABP and FN protein in kidney was detected by immunohistochemistry. The level of serum IgA, urinary albumin and urinary hL-FABP was detected by ELISA. Results (1) IgAN was reconstituted in both Tg and WT mice by BMT: mesangial IgA deposition and up-regulation of serum IgA. The levels were not significantly different between two groups (Tg-ddY and WT-ddY). (2) hL-FABP was expressed in proximal tubular cells of normal Tg mice. The mRNA (1.62±0.32 vs 0.46±0.09, P<0.01) and protein expression (1.74±0.76 vs 1.14±0.31, P<0.01) of hL-FABP was up-regulated in Tg-ddY kidney and urinary hL-FABP level (?滋g/g creatinine) was significantly increased (59.87±26.75 vs 31.01±14.86, P<0.05) at the 6th week after BMT. (3) WT-ddY mice showed a significantly higher urinary albumin level (mg/L) (828±656 vs 82±22, P<0.01), severer mesangial matrix expansion (P<0.01),more glomerular FN and Col Ⅳ deposition at the 12th week. (4) Up-regulation of renal hL-FABP was associated with significant suppression of renal HO-1 expression (P<0.05), accumulation of 4-HNE modified proteins (P<0.05) and MCP-1 mRNA expression (P<0.01) in Tg-ddY mice. Conclusion Tubular L-FABP may lessen the progression of glomerular damage at early stages of IgAN by reducing oxidative stress and inflammatory mediators.