Urine in Clinical Proteomics

Abstract

Urine has become one of the most attractive biofluids in clinical proteomics as it can be obtained non-invasively in large quantities and is stable compared with other biofluids. The urinary proteome has been studied by almost any proteomics technology, but mass spectrometry-based urinary protein and peptide profiling has emerged as most suitable for clinical application. After a period of descriptive urinary proteomics the field is moving out of the discovery phase into an era of validation of urinary biomarkers in larger prospective studies. Although mainly due to the site of production of urine, the majority of these studies apply to the kidney and the urinary tract, but recent data show that analysis of the urinary proteome can also be highly informative on non-urogenital diseases and used in their classification. Despite this progress in urinary biomarker discovery, the contribution of urinary proteomics to the understanding of the pathophysiology of disease upon analysis of the urinary proteome is still modest mainly because of problems associated to sequence identification of the biomarkers. Until now, research has focused on the highly abundant urinary proteins and peptides, but analysis of the less abundant and naturally existing urinary proteins and peptides still remains a challenge. In conclusion, urine has evolved as one of the most attractive body fluids in clinical proteomics with potentially a rapid application in the clinic.

Effects of endurance exercise on the urinary proteome analyzed by 2‐D PAGE and Orbitrap MS

“…Nevertheless, urinary proteomics can be used in clinical diagnosis of renal diseases and essential changes in the urinary proteome can serve as indication for physiological changes [1].…”

Developing a kidney and urinary pathway knowledge base

“…The data spans multiple -omic levels and is collected from different tissues and from different species. For example, most of the human -omics data originates from urine [4] and needs to be related back to the kidney and its parts. In contrast, multilevel -omics data from animal models is more regularly available.…”

Toward Quantitative Proteomics of Organ Substructures: Implications for Renal Physiology

“…Similarly, Knepper and colleagues detected nearly 1100 proteins in human urinary exosomes and also determined phosphorylation sites 80 . Major achievements of urine proteomics have been reviewed elsewhere 3,4,81 . Clearly, major limitations in this field are that potential markers still require validation and that panels of markers rather than single markers may be needed for diagnosis and monitoring of disease progression.…”

“…This review will focus on three areas of active research: 1) new developments in proteome technology allowing detection and quantitation of proteins in very small samples, 2) 4 novel methods enriching specific organ structures and cells using mouse lines expressing fluorescent proteins under organ-or cell specific promoters, and 3) application of these new developments to the kidney. Here we will mainly cover aspects relating to proteomics of solid organ structures; excellent reviews have recently described the state-of-the-art and challenges of urine proteomics [3][4][5] .…”