磁共振功能成像方法评价P选择素单抗对狼疮性肾炎肾损害的干预作用

发布时间：2018-02-24 18:06

本文关键词： 狼疮性肾炎肾小管间质病变 P-选择素磁共振功能成像　出处：《上海交通大学》2015年博士论文　论文类型：学位论文

【摘要】：狼疮性肾炎(LN)是我国最常见的继发性肾小球肾炎之一,主要临床表现为蛋白尿、血尿,严重者可出现肾病综合征,甚至肾功能不全。2003年国际肾脏病协会和肾脏病理组织(ISN/RPS)主要依据肾小球病变情况对LN进行了分型。事实上,60%~70%LN患者可出现不同程度的肾小管损害、肾间质炎症和纤维化,而且肾小管间质病变的严重程度直接影响了LN的进展速度和预后。在LN的小管间质病变发生过程中,免疫损伤可能导致肾血管内皮细胞活化、组织缺血缺氧,肾内活性氧(ROS)大量产生,在ROS、P-选择素以及促分裂素原活化蛋白激酶作用下中性粒细胞聚集粘附,进而加重了肾小管间质损伤。细胞黏附分子P-选择素主要表达在活化的血小板/内皮细胞表面,是在炎症早期介导中性粒细胞于血管内皮滚动和初始黏附的关键成分,可促使炎症部位中性粒细胞募集,在LN小管间质病变中可能起到重要作用。本研究利用磁共振(MR)功能成像方法观察经P-选择素单克隆抗体治疗前后LN动物模型(MRL/lpr小鼠)肾脏的功能、缺氧状态和病理变化,探讨LN肾小管间质病变的病理机制以及P-选择素单抗对LN的早期干预和治疗作用,同时探讨MR功能成像在狼疮性肾炎肾脏病变、氧合水平的动态监测和疗效评估方面的价值。研究的第一部分对65例LN患者和16例健康志愿者进行了肾脏扩散加权成像(DWI)及血氧水平依赖法(BOLD)成像。分析LN患者的肾脏表观扩散系数(ADC)和表观自旋-自旋弛豫率(R2*)值与临床指标和病理改变的关系。结果发现LN肾脏的ADC值为(2.40±0.25)x10-3mm2/s,皮、髓质R2*值分别为11.03±1.60/sec和14.05±3.38/sec,均显著低于正常肾脏测值(分别P=0.048,P=0.045和P=0.008)。LN肾脏ADC值与eGFR显著相关(r=0.510,P0.01),与肾脏病理慢性指数呈负相关(r=-0.249,P0.05)。髓质R2*值与24小时尿蛋白、肾小管间质病变程度均呈负相关(r分别为-0.244和-0.242,P0.05)。65例LN患者中16例经过9~12个月免疫诱导治疗后再次行MR功能成像,发现完全缓解者肾脏ADC值和R2*值较前显著升高。研究表明DWI成像和BOLD成像检查为动态监测LN肾功能损害和肾组织病理改变提供了一种无创性方法,可能为临床干预的疗效评价提供依据。研究的第二部分以自发性LN模型MRL/lpr小鼠作为研究对象,其尿蛋白、血清肌酐、抗ds-DNA抗体均显著高于对照组C57BL/6小鼠,自12周龄起肾小球系膜细胞增生、基底膜增厚,肾小管上皮细胞脱落,肾间质炎细胞浸润,尤其是血管周围炎细胞大量聚集。采用免疫组化、Western blot方法发现在LN模型小鼠肾组织中有缺氧探针HypoxyprobeTM-1、缺氧标志物HIF-1α和对组织缺氧有保护作用的HO-1蛋白广泛分布,并与肾小管间质病变密切相关,MR功能成像肾脏ADC值与尿蛋白、血肌酐呈负相关,平均R2*值与尿蛋白、肾小管间质病变程度及肾组织缺氧指标表达均呈负相关。结果提示肾内缺氧是导致LN肾小管间质病变的关键因素之一,功能MRI可反映LN肾脏病变及肾内缺氧情况。研究的第三部分采用免疫组化、Western blot和实时荧光定量PCR方法发现LN小鼠肾组织中P-选择素蛋白和m RNA表达显著上调。采用P-选择素单抗对MRL/lpr小鼠进行早期干预,缺氧探针HypoxyprobeTM-1、HIF-1α和HO-1蛋白分布和mRNA表达较未干预组和生理盐水对照组均下降,且肾小管间质病变的严重程度减轻。MR功能成像R2*值与肾小管间质病变程度及肾组织缺氧指标表达均呈负相关。提示P-选择素在LN肾组织表达上调,可能参与启动LN肾小管间质早期的炎症反应和病理损伤,BOLD-MRI可动态监测LN干预前后肾内氧合状态。总之,本研究表明肾内缺氧可能是导致LN肾小管间质病变的一个关键因素,P-选择素单抗干预可改善LN肾内缺氧及肾小管间质病变程度,功能MRI为动态监测LN肾脏病变、氧合水平和疗效评价提供了一种无创性方法,对于临床上LN的早期诊治、疗效监测和预后评估具有重要意义。
[Abstract]:Lupus nephritis (LN) is one of the most common secondary glomerulonephritis in our country, the main clinical manifestations were proteinuria, hematuria, serious person can appear in nephrotic syndrome, and renal insufficiency in.2003 international society of Nephrology and renal pathology (ISN/RPS) mainly on the basis of glomerular lesions were divided into type of LN. In fact, 60%~70%LN can occur in patients with renal tubular injury and renal interstitial inflammation and fibrosis, and the severity of tubulointerstitial changes directly affect the progression and prognosis of LN. In the process of quality LN tubule lesions, immune injury may lead to renal vascular endothelial cell activation, organization hypoxia ischemia, active oxygen in the kidney (ROS) produced in ROS, P-, P-selectin and mitogen activated protein kinase in neutrophil adhesion and aggregation effect, aggravate tubulointerstitial injury. Cell adhesion molecule P- selectin is mainly expressed on the surface of activated platelet / endothelial cells, is a key ingredient in the early stage of inflammation mediated neutrophil adhesion to vascular endothelial rolling and initial, can promote inflammation neutrophil recruitment, LN in tubulointerstitial lesions may play an important role. This study used magnetic resonance (MR) functional imaging method to observe the P- element before and after monoclonal antibody in LN animal model (MRL/lpr mouse) renal function status and pathological changes of hypoxia, early intervention and treatment effect of LN on renal tubule pathological lesions and mechanism of P- selectin monoclonal antibody on LN, at the same time to explore the functional MR imaging in renal lesions of lupus nephritis dynamic monitoring and evaluation, effect of oxygenation value. The first part of the study of 65 LN patients and 16 healthy volunteers were renal diffusion weighted imaging (DWI) and blood oxygen level dependent Lai (BOLD) imaging method. Analysis of apparent diffusion coefficient in patients with kidney LN (ADC) and apparent spin spin relaxation rate (R2*) value and clinical indicators and pathological changes. The results showed that LN kidney ADC value (2.40 + 0.25) x10-3mm2/s, skin, medulla R2* = 11.03 1.60 + /sec and 14.05 + 3.38/sec were significantly lower than that of normal renal values (respectively P=0.048, P=0.045 and P=0.008).LN renal ADC value was significantly correlated with eGFR (r=0.510, P0.01), and negatively correlated with renal pathological chronic index (r=-0.249, P0.05). The R2* values of medulla and urine protein of 24 hours, the degree of renal tubule matter lesions were negatively correlated (r = -0.244 and -0.242, P0.05).65 LN patients in 16 cases after 9~12 months after treatment again for MR induced immune function imaging, found complete remission of renal ADC and R2* values significantly increased. The research showed that DWI and BOLD as imaging examination for dynamic monitoring LN renal function Changes of renal pathological damage and provides a noninvasive method, may provide the basis for the evaluation of curative effect for clinical intervention. The second part of the study on spontaneous LN model MRL/lpr mice as the research object, the urine protein, serum creatinine, anti ds-DNA antibodies were significantly higher than the control group of C57BL/6 mice, the proliferation of mesangial cells from at the age of 12 weeks, basement membrane thickening, renal tubular epithelial cell shedding, renal interstitial infiltration of inflammatory cells, especially the large accumulation of perivascular inflammatory cells. Immunohistochemical method, Western blot found that hypoxia probe HypoxyprobeTM-1 in renal tissue of LN mice, hypoxia marker HIF-1 alpha and has a protective effect on hypoxia HO-1 protein is widely distributed, and tubulointerstitial lesions are closely related, MR functional imaging of renal ADC value and urinary protein was negatively correlated with serum creatinine, the average value of R2* and urinary protein, renal tubular interstitial lesion Hypoxia index and renal tissue expression showed a negative correlation. The results showed that renal hypoxia is one of the key factors leading to mass lesions of the LN renal tubule function, MRI can reflect the renal lesions and renal hypoxia LN. The third part of the study by immunohistochemistry, Western blot and real-time fluorescence quantitative PCR method found that P- selectin m RNA and protein expression was significantly up-regulated in renal tissue of LN mice. The P- selectin monoclonal antibody for early intervention of MRL/lpr mice, hypoxia probe HypoxyprobeTM-1, expression of HIF-1 and HO-1 protein distribution and mRNA than those in the untreated group and saline control group were decreased, and the severity of renal tubulointerstitial lesions reduce functional.MR imaging R2* the value of renal tubule and hypoxia index matter lesions and renal tissue expression were negatively correlated. P- selectin in renal LN expression may be involved in the early start LN tubulointerstitial inflammation And the pathological injury and BOLD-MRI dynamic monitoring of LN before and after the intervention of renal oxygenation. In conclusion, this study shows that hypoxia may lead to LN in renal tubulointerstitial lesions is one of the key factors, P- selectin monoclonal antibody intervention can improve the severity of renal LN hypoxia and renal tubule function, MRI LN kidney disease dynamic monitoring, evaluation of the oxygenation level and curative effect provides a noninvasive method for early diagnosis and treatment of clinical LN, has important significance for evaluation of curative effect monitoring and prognosis.

【学位授予单位】：上海交通大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：R593.242

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