Application of proteomic analysis to the study of renal diseases

Proteomics-based approaches are generating considerable data in clinical nephrology covering almost all aspects of the discipline. Proteomic experiments commonly involve fractionation and protein separation, followed by mass spectrometric analysis to identify proteins and peptides. Biostatistical and bioinformatical input is essential in such experiments, from initial experimental design to analysis of data. Standardization of procedures is an important research objective. Depending on study design, results can lead to biomarker discovery, mechanistic insight and identification of potential avenues for therapeutic intervention and treatment evaluation. Understanding proteomic information and its place in current clinical research and practice is fundamental. This Review describes proteomic experimentation and the concepts behind it, and gives an overview of its application to important areas in clinical nephrology including acute kidney injury, chronic kidney disease, end-stage renal disease, genetic diseases and fluid and electrolyte disorders, with a particular focus on biomarker discovery. The importance of future developments, such as the establishment of an infrastructure for a 'biomarker pipeline' with structured validation pathways for candidate biomarkers and development of clinical assays, is also discussed and some future perspectives are presented.