Variabilities of serum peptidomics spectra in patients with IgA nephropathy

Objective To study the variabilities of serum peptidomics spectra in patients with IgA nephropathy (IgAN) and to screen for biomarkers in the early diagnosis of IgAN. Methods Patients with IgAN or other kidney diseases and healthy individuals registered to the Department of Nephrology, No. 181 Hospital of Chinese People' s Liberation Army, from August 2008 to March 2009 were recruited in this study, who were divided into the study group and the control groups. The study group included 33 patients with IgAN (IgAN group), while the control groups included 10 healthy volunteers, 12 patients with minimal change nephrotic syndrome (MCNS) , 10 with focal segmental glomerulosclerosis (FSGS) and 10 with membranous nephropathy (MN). Magnetic bead enrichment and MALDI-TOF-MS were used to analyze the variabilities of serum peptidomics spectra between IgAN group and other groups based on ClinProt system.Results A total of 5, 5, 3 and 3 differential peptide peaks, respectively, were selected as potential biomarkers for diagnosis of IgAN and healthy volunteers, MCNS, FSGS and MN. Conclusion A serum peptide fingerprint model based on proteomics technology is successfully established for diagnosis of IgAN,which may provide a novel view to understand application of proteomics in early diagnosis of IgAN. Key words: Nephropathy,IgA; Peptide mapping; Proteomics; Mass spectrometry; ClinProt system