National Clinical Research Center of Kidney Diseases, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210002, P.R. China.
Mol Med Rep. 2017 Nov;16(5):6276-6284. doi: 10.3892/mmr.2017.7329. Epub 2017 Aug 22.
Nephrotic syndrome is not a single disease; rather, it is a term for numerous diseases and pathological types. Renal biopsy is of use in determining the diagnosis and prognosis, and for guiding treatment; however, the use of this intervention is limited due to its invasive nature. Abnormal kidney‑derived proteins in the urine of patients provide useful information regarding numerous pathological processes that occur in the kidneys, and may be considered a potential non‑invasive biomarker for kidney disease. Proteomic analysis exhibits the advantage of being high‑throughput and has previously been used to identify biomarkers of disease. The present study aimed to identify abnormal kidney‑derived proteins in the urine of patients with nephrotic syndrome using a novel proteomic strategy. Urine samples from 5 patients with nephrotic syndrome were subjected to acetone precipitation and albumin/immunoglobulin G depletion prior to analysis by two‑dimensional liquid chromatography tandem mass spectrometry. The resulting data were compared to a publicly available proteomic database of normal human plasma/urine and normal human kidney in PeptideAtlas, and of normal human kidney in the Human Protein Atlas. Candidate biomarkers were validated using ELISA analysis in 60 patients with nephrotic syndrome: 30 with focal segmental glomerulosclerosis (FSGS) and 30 with minimal change disease (MCD), as well as in 30 healthy controls. The initial screening identified 809 proteins in the urine of patients with nephrotic syndrome. A total of 13/809 proteins were additionally present in the kidney proteome of PeptideAtlas and the Human Protein Atlas, although not in normal human urine and normal human plasma according to PeptideAtlas; these were referred to as 'kidney‑derived disease‑associated proteins'. One of the kidney‑derived disease‑associated proteins, ubiquitin‑60S ribosomal protein L40 (UBA52) was observed to be increased in the urine of patients compared with normal controls [Creatinine, 637 ng/mg (216‑1,851) vs. 1.89 ng/mg (1.37‑3.33), P<0.001; and 18.58 ng/mg (11.11‑46.25) vs. 1.89 ng/mg (1.37‑3.33), P<0.001)], and the urinary UBA52 levels were significantly increased in patients with FSGS compared with in patients with MCD (P<0.001). In conclusion, the present study identified potential novel urinary protein biomarkers for nephrotic syndrome, in addition to an extensive urinary proteomic profile of patients with nephrotic syndrome.
肾病综合征不是一种单一的疾病，而是多种疾病和病理类型的总称。肾活检有助于确定诊断和预后，并指导治疗；然而，由于其侵袭性，这种干预的应用受到限制。患者尿液中的异常肾脏来源蛋白提供了有关肾脏中发生的许多病理过程的有用信息，并且可以被视为肾脏疾病的潜在非侵入性生物标志物。蛋白质组学分析具有高通量的优势，并且以前曾用于鉴定疾病的生物标志物。本研究旨在使用新型蛋白质组学策略鉴定肾病综合征患者尿液中的异常肾脏来源蛋白。将 5 例肾病综合征患者的尿液样本进行丙酮沉淀和白蛋白/免疫球蛋白 G 耗尽，然后通过二维液相色谱串联质谱分析。将得到的数据与 PeptideAtlas 中正常人类血浆/尿液和正常人类肾脏的公开蛋白质组数据库以及 Human Protein Atlas 中正常人类肾脏的数据库进行比较。使用 ELISA 分析在 60 例肾病综合征患者（30 例局灶节段性肾小球硬化症（FSGS）和 30 例微小病变性疾病（MCD））和 30 例健康对照中验证候选生物标志物。初步筛选在肾病综合征患者的尿液中鉴定出 809 种蛋白质。总共 13/809 种蛋白质还存在于 PeptideAtlas 和 Human Protein Atlas 的肾脏蛋白质组中，尽管根据 PeptideAtlas，它们不存在于正常人类尿液和正常人类血浆中；这些被称为“肾脏疾病相关蛋白”。在尿液中观察到一种肾脏疾病相关蛋白，泛素-60S 核糖体蛋白 L40（UBA52）在患者中比正常对照增加[肌酐，637ng/mg（216-1851）比 1.89ng/mg（1.37-3.33），P<0.001；和 18.58ng/mg（11.11-46.25）比 1.89ng/mg（1.37-3.33），P<0.001）]，并且 FSGS 患者的尿 UBA52 水平明显高于 MCD 患者（P<0.001）。总之，本研究鉴定了肾病综合征的潜在新型尿蛋白生物标志物，以及肾病综合征患者广泛的尿蛋白质组图谱。
