抗体介导的慢性排斥反应中内皮细胞基因的变化及分子机制

目前,抗体介导的慢性肾移植排斥反应难以预测,尚无有效的治疗方法。研究表明,通过对内皮细胞相关基因的分析,可以提高抗体介导的慢性肾移植排斥反应术前及术后的诊断特异性。该病的发病机制主要包括四个方面：（1）血小板在内皮细胞附近聚集凝固能力增强;（2）内皮细胞趋化炎性细胞作用增强;（3）干扰素-γ（IFN-γ）杀伤作用增强：（4）内皮修复再生能力降低。基因分析结合抗体分析有助于深化理解抗体介导的肾移植排斥反应的发病机理、提高诊疗效果、为新药开发提供新靶点,使肾移植成功率大幅提高成为可能。该篇综述将就上述内容作一介绍。     

Diagnostic Performance of Echocardiography for the Detection of Acute Cardiac Allograft Rejection: A Systematic Review and Meta-Analysis

Objective

Many studies have addressed the diagnostic performance of echocardiography to evaluate acute cardiac allograft rejection compared with endomyocardial biopsy. But the existence of heterogeneity limited its clinical application. Thus, we conducted a comprehensive, systematic literature review and meta-analysis for the purpose.

Methods

Studies prior to September 1, 2014 identified by Medline/PubMed, EMBASE and Cochrance were examined by two independent reviews. We conducted meta-analysis by using Meta-DiSc 1.4 software. An assessment tool of QUADAS-2 was applied to evaluate the risk of bias and applicability of the studies.

Results

Thirty studies met the inclusion criteria of meta-analysis. The four parameters of pressure half time, isovolumic relaxation time, index of myocardial performance and late diastolic mitral annular motion velocity were included in the meta-analysis, with a pooled diagnostic odds ratio of 10.43, 6.89, 15.95 and 5.68 respectively, and the area under the summary receiver operating characteristic curves value of 0.829, 0.599, 0.871 and 0.685 respectively.

Conclusion

The meta-analysis and systematic review demonstrate that no single parameter of echocardiography showed a reliable diagnostic performance for acute cardiac allograft rejection. A result of echocardiography for ACAR should be comprehensively considered by physicians in the context of clinical presentations and imaging feature.     

大鼠肾移植慢性排斥反应模型的建立

目的建立一种稳定的大鼠原位肾移植慢性排斥反应模型。方法供体为近交系F344大鼠,受体为Lewis大鼠,供肾采用左肾,在体修整,原位灌注。肾静脉用硬膜外导管做为临时内支架管端-端、六针法吻合,腹主动脉端-侧连续缝合,输尿管带膀胱瓣与膀胱吻合。受体术前3 d开始环孢素A灌胃至术后30 d（5 mg/kg·d）,以预防急性排斥反应。结果手术时间120～180 min;手术成功率90.9%（40P44）;受体均存活60 d。并发症有吻合口出血、静脉血栓形成、急性排斥反应等。结论供肾原位灌注,在体修整是简单可靠的方法。静脉內支架管端端吻合,腹主动脉端侧吻合能够达到稳定的成功率,值得推广。熟练的外科操作技能和血管吻合技术是手术成功的关键。     

肝移植急性排斥反应时外周血Th17细胞的特征及意义

目的:观测肝移植患者术前及术后急性排斥时外周血中Th17细胞频率变化特征,探讨其与肝移植术后急性排斥发生的关系。方法:对18例于我院进行肝移植手术的患者进行随访研究,应用流式细胞仪检测各随访点外周血中Th17细胞频率。随访期间发生急性排斥反应的患者为急排组(n=7,男女比为5/2),未发生急性排斥反应者为非急排组(n=11,男女比为8/3),比较两组患者肝移植前后外周血中Th17细胞频率的变化规律。结果:急排组与非急排组患者肝移植术前外周血中Th17细胞频率无统计学差异(P=0.672),而急排组患者发生急性排斥反应时与非急排组患者相比Th17细胞频率明显升高(P=0.002)。在随访研究中,急排组患者在发生急性排斥反应时外周血中Th17细胞频率较未发生急性排斥反应时增高,且Th17细胞频率与ALT变化趋势一致,呈明显正性相关。而非急排组患者术后随访期间外周血中Th17细胞频率无统计学差异。结论:肝移植患者术后发生急性排斥反应时外周血中Th17细胞频率明显升高,变化趋势与ALT水平一致,呈正性相关,可能成为诊断急性排斥反应的潜在指标。     

Identification of Common Prognostic Gene Expression Signatures with Biological Meanings from Microarray Gene Expression Datasets

Numerous prognostic gene expression signatures for breast cancer were generated previously with few overlap and limited insight into the biology of the disease. Here we introduce a novel algorithm named SCoR (Survival analysis using Cox proportional hazard regression and Random resampling) to apply random resampling and clustering methods in identifying gene features correlated with time to event data. This is shown to reduce overfitting noises involved in microarray data analysis and discover functional gene sets linked to patient survival. SCoR independently identified a common poor prognostic signature composed of cell proliferation genes from six out of eight breast cancer datasets. Furthermore, a sequential SCoR analysis on highly proliferative breast cancers repeatedly identified T/B cell markers as favorable prognosis factors. In glioblastoma, SCoR identified a common good prognostic signature of chromosome 10 genes from two gene expression datasets (TCGA and REMBRANDT), recapitulating the fact that loss of one copy of chromosome 10 (which harbors the tumor suppressor PTEN) is linked to poor survival in glioblastoma patients. SCoR also identified prognostic genes on sex chromosomes in lung adenocarcinomas, suggesting patient gender might be used to predict outcome in this disease. These results demonstrate the power of SCoR to identify common and biologically meaningful prognostic gene expression signatures.     

Signatures of miR-181a on the Renal Transcriptome and Blood Pressure

MicroRNA-181a binds to the 3′ untranslated region of messenger RNA (mRNA) for renin, a rate-limiting enzyme of the renin-angiotensin system. Our objective was to determine whether this molecular interaction translates into a clinically meaningful effect on blood pressure and whether circulating miR-181a is a measurable proxy of blood pressure. In 200 human kidneys from the TRANScriptome of renaL humAn TissuE (TRANSLATE) study, renal miR-181a was the sole negative predictor of renin mRNA and a strong correlate of circulating miR-181a. Elevated miR-181a levels correlated positively with systolic and diastolic blood pressure in TRANSLATE, and this association was independent of circulating renin. The association between serum miR-181a and systolic blood pressure was replicated in 199 subjects from the Genetic Regulation of Arterial Pressure of Humans In the Community (GRAPHIC) study. Renal immunohistochemistry and in situ hybridization showed that colocalization of miR-181a and renin was most prominent in collecting ducts where renin is not released into the systemic circulation. Analysis of 69 human kidneys characterized by RNA sequencing revealed that miR-181a was associated with downregulation of four mitochondrial pathways and upregulation of 41 signaling cascades of adaptive immunity and inflammation. We conclude that renal miR-181a has pleiotropic effects on pathways relevant to blood pressure regulation and that circulating levels of miR-181a are both a measurable proxy of renal miR-181a expression and a novel biochemical correlate of blood pressure.     

基于WGCNA和SVM-RFE算法挖掘肺腺癌诊断和预后基因标志物

目的 肺癌是世界上最常见的癌症之一,在众多肺癌患者中,肺腺癌(lung adenocarcinoma,LUAD)的死亡率最高.基因表达谱的变化与肿瘤的发生和发展过程有关,通过识别与LUAD患者相关的诊断和预后基因标志物,可以为肺腺癌的预防和治疗提供理论依据.方法 本研究以肿瘤基因组图谱(The Cancer Gene ...     

Urinary Peptidomic Analysis Identifies Potential Biomarkers for Acute Rejection of Renal Transplantation

Introduction  Human urine is a complex matrix of proteins, endogenous peptides, lipids, and metabolites. The level of any or all of these components can reflect the pathophysiological status of an individual especially of the kidney at the time of urine collection. The naturally occurring endogenous urinary peptides which are thought to be the product of several proteolytic and degradation processes may provide clinically useful biomarkers for different renal and systemic diseases. Materials and Methods  To examine if specific differences in the urinary peptidome (<10 kDa) occur at the time of acute renal transplant rejection (AR), we undertook a study of urine samples collected from biopsy-proven AR (n = 10), stable graft function (n = 10), and healthy normal control (n = 10). The peptides (<10 kDa) were extracted and fractionated with high-performance liquid chromatography followed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometric (MS) analysis. Results  We identified 54 endogenous peptides, including multiple peptides for Tamm–Horsfall protein (UMOD). A panel of peptides are identified which discriminate renal transplant patients with AR from stable graft. We have shown that liquid chromatography followed by MALDI is a useful tool to identify potential biomarkers, which after verification with larger patient cohort can be used as a non-invasive monitoring tool for renal transplant rejection.     

同种异体心脏移植中急性排斥反应免疫学机制及进展

目前,同种异体心脏移植已成为一种应用于临床治疗终末期心脏病的较为有效方法.急性排斥反应是目前同种异体心脏移植中最常见的一种移植免疫排斥反应,是心脏移植第一年失败的主要原因.因此,解决和研究心脏移植中急性排斥反应及其发生机制,己成为当今临床移植研究的紧迫课题.现就其免疫学机制,目前研究现状及进展等作一综述.     

Delta Neutrophil Index as a Marker for Differential Diagnosis between Acute Graft Pyelonephritis and Acute Graft Rejection

Introduction

The delta neutrophil index (DNI) is the fraction of circulating immature granulocytes, which reflect infectious and/or septic condition. Acute graft pyelonephritis (AGPN) versus acute graft rejection is a frequently encountered diagnostic and therapeutic dilemma in kidney transplant recipients, but little is known about the clinical usefulness of DNI value in the differentiation of the two conditions.

Material & Methods

A total of 90 episodes of AGPN or acute graft rejection were evaluated at the Kangdong Sacred Heart Hospital between 2008 and 2014. We performed retrospective analysis of demographic, clinical, and laboratory parameters data. Receiver operating curves (ROC) and multivariate logistic regression were conducted to ascertain the utility of DNI in discriminating between AGPN and acute graft rejection.

Results

AGPN group had significantly higher DNI values than acute graft rejection group (2.9% vs. 1.9%, P < 0.001). The area under the ROC curve for DNI value to discriminate between AGPN and acute graft rejection was 0.85 (95% confidence interval [CI]; 0.76–0.92, P < 0.001). A DNI value of 2.7% was selected as the cut-off value for AGPN, and kidney transplant recipients with a DNI value ≥ 2.7% were found to be at a higher risk of infection than those with a DNI < 2.7% (odd ratio [OR] 40.50; 95% CI 8.68–189.08; P < 0.001). In a multivariate logistic regression analysis, DNI was a significant independent factor for predicting AGPN after adjusting age, sex, log WBC count, log neutorphil count, log lymphocyte count, CRP concentration, and procalcitonin concentration (OR 4.32; 95% CI 1.81–10.34, P < 0.001).

Conclusions

This study showed that DNI was an effective marker to differentiate between AGPN and acute graft rejection. Thus, these finding suggest that DNI may be a useful marker in the management of these patients.     

两型肾癌的共同标志物筛选及机制研究

目的 肾细胞癌是一种源发于肾小管上皮系统的恶性肿瘤。在已有肾癌相关mi RNA标志物的研究中,大都忽略了不同亚型肾癌之间样本数据量差距对筛选结果的影响,这会导致mi RNA生物标志物对不同亚型肾癌患者的诊断能力存在较大差异,进而发生漏诊误诊。因此本课题考虑了两种亚型肾癌共同标志物进行研究。方法 对透明肾细胞癌（KIRC）和乳头状肾细胞癌（KIRP）的表达谱数据分别进行统计学和两种机器学习方法筛选并对结果取交集获得两型肾癌共同mi RNA标志物。接着,用ROC方法验证了这些标志物的诊断能力。用机器学习方法对外部数据集KICH进行了验证,进一步证明这些标志物的诊断能力以及避免过拟合。还用已有实验文献验证了这些标志物的合理性。用生物信息学方法对mi RNA标志物分子机制进行研究。结果 获得了6个两型肾癌共同mi RNA标志物（mi R-21、mir-210、mir-185、mir-188、mir-362、mir-199a-2）,其中有4个已有实验报道和肾癌密切相关,而mir-188和mir-199a-2尚未见文献报道其与肾癌相关,可能是新的肾癌相关mi RNA标志物。之后对6个两型肾癌共同m...     

PD-L1 Ig在缓解肾移植急性排斥反应中的免疫调节作用

目的:探讨PD-L1 Ig(Programmed death ligand-1 immunoglobulin,程序性死亡配体-1免疫球蛋白)在缓解肾移植急性排斥反应中的免疫调节作用。方法:选择健康成年雄性Lewis大鼠24只作为供体,另取24只健康雄性Wistar大鼠作为受体。所选大鼠3个月龄,体重300 g±30 g,创建肾移植大鼠模型,并将其随机分为三组,空白对照组,对照组,和PD-L1 Ig组。空白对照组:灌注液,肾动脉灌注3分钟。PD-L1 Ig组:含1 m L的PD-L1 Ig的灌注液,肾动脉灌注3分钟。对照组不进行额外灌注操作。术后观察三组大鼠食欲、精神状态及生存情况。7天后取血标本观察肌酐、尿素氮、γ-干扰素(Interferon-γ, IFN-γ),白细胞介素-2(Interleukin-2, IL-2),白细胞介素-10 (Interleukin-10, IL-10)水平,同时三组各处死3只大鼠行肾脏病理学检查。结果:1.病理:对照组及空白对照组大鼠较模型大鼠有改善,仍有较多的炎细胞浸润,间质水肿,红细胞管型,肾小管上皮细胞脱落。而PD-L1 Ig组大鼠较模型大鼠、对照组及空白对照组有显著改善。2.生存状态和肾功能:PD-L1 Ig组大鼠生存时间最长50天,平均存活时间和体重均显著高于对照组和空白对照组,差异均有统计学意义(P0.05);血肌酐、尿素氮水平显著低于对照组和空白对照组,差异均有统计学意义(P0.05)。3.细胞因子变化:PD-L1 Ig组IFN-γ、IL-2水平显著低于空白对照组、对照组,差异均有统计学意义(P0.05);PD-L1 Ig组IL-10水平显著高于空白对照组、对照组,差异均有统计学意义(P0.05)。结论:PD-L1 Ig可降低IL-2和IFN-γ,提升IL-10,调节移植肾急性排斥反应的细胞因子平衡,改善肾功能,延长移植肾存活时间。