Preliminary Communication

Background.Proteomic technologies offer a highthroughput 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.