[Discovery of disease biomarkers by ProteinChip system; clinical proteomics as noninvasive diagnostic tool].

Biopsy-associated complications could not be eliminated in spite of recent refinement, although needle biopsy has been the standard test for diagnosis of renal diseases. The development of noninvasive diagnostic test that provides insights into the mechanisms of diseases would be expected in the field of laboratory medicine. Biological fluids potentially have important histological information whose determination could serve to detect early disease state. Recently the advent of SELDI-TOF-MS (surface-enhanced laser desorption/ionization time-of-flight mass spectrometry) has extended the application of mass spectrometry to the study of proteins in biological fluids. We applied a new protein-chip technology based on SELDI in a discovery of renal disease biomarkers. Proteomic patterns in serum by means of protein-chip were exemplified by elucidating a biomarker candidate for acute renal allograft rejection. SELDI protein-chip technology will be applied more frequently to a number of medical and basic research problems because of high resolution, high reproducibility, ease of use, and fentomole sensitivity.