Membranous nephropathy (MN) is one of the most common causes of primary glomerular diseases worldwide. The M-type phospholipase A2 receptor (PLA2R), an antigen expressed in more than 70% of cases of idiopathic membranous nephropathy (IMN), is a biomarker which is now used by physicians for clinical diagnosis. Despite the prevalence of PLA2R in the cases of MN, it is not always effective to use PLA2R for differentiating primary or secondary MNs. On the other hand, urinary albumin assay is one of the de facto tests for kidney function testing for several decades. In this work, urinary albumin species between primary and secondary MN patients are compared using a newly developed capillary isoelectric focusing - mass spectrometry (CIEF-MS) technology. The distinct patterns of cationic and acidic urinary albumin species, as revealed by this novel CIEF-MS technology, suggest potential applications of this differential analysis for subtyping of membranous nephropathy. Further investigation of these cationic human albumin species in urine may provide clues to the disease onset and development of MN, thus facilitating treatment. In addition, this novel workflow of using CIEF-MS for urinary protein analysis may be beneficial to the research, pathology, prognosis, and diagnosis of many other types of kidney diseases, such as chronic kidney disease, diabetic nephrology, etc.

中文翻译：

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在线毛细管等电聚焦质谱法对膜性肾病患者尿白蛋白的差异分析

膜性肾病（MN）是世界范围内原发性肾小球疾病的最常见原因之一。M型磷脂酶A2受体（PLA2R）是一种生物标志物，在70％以上的特发性膜性肾病（IMN）病例中表达，是一种生物标志物，现已被医生用于临床诊断。尽管在MN病例中普遍使用PLA2R，但使用PLA2R区分主要或次要MN并不总是有效的。另一方面，数十年来，尿白蛋白测定是肾功能检查的事实上的检查之一。在这项工作中，使用新开发的毛细管等电聚焦质谱（CIEF-MS）技术比较了原发性和继发性MN患者之间的尿白蛋白种类。阳离子和酸性尿白蛋白种类的不同模式，正如这项新颖的CIEF-MS技术所揭示的，表明这种差异分析在膜性肾病亚型分析中的潜在应用。对尿液中这些阳离子人白蛋白种类的进一步研究可为MN的发病和发展提供线索，从而促进治疗。此外，使用CIEF-MS进行尿蛋白分析的这种新颖的工作流程可能有益于许多其他类型的肾脏疾病（例如慢性肾脏病，糖尿病肾病等）的研究，病理，预后和诊断。