Proteomic profiling and identification in peritoneal fluid of children treated by peritoneal dialysis

Abstract

Background. Proteomic technologies offer a high-throughput analysis of the expression of proteins in biological samples. The global analysis of the proteins in peritoneal dialysis (PD) fluid will provide a better understanding of the biological processes of the peritoneal membrane. Methods. The dialysate of nine paediatric PD patients was collected from peritoneal equilibrium tests with 3.86% glucose. Proteins were separated on a 10% SDS-PAGE gel and in-gel digested with trypsin. Peptide mixtures were analysed using nanoLC-MS/MS and results were searched against the NCBI database. Results. A total number of 189 proteins were identified in the PD fluid of nine patients, with 88 proteins shared by all patients. These 88 proteins accounted for 47% of the identified proteins and >90% of the total protein content in the analysed samples. Proteins were subdivided into eight different classes according to function. Conclusions. This study gives a representative overview of the proteins present in PD fluid. The proteins in PD fluid reflect plasma proteins as well as local peritoneal processes. Potentially interesting proteins are revealed. © The Author [2008]. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.