血清プロテオーム研究のための試料調製

抄録

Biomarkers in some studies are profiling-based and have limitation in clinical use, particularly due to the lack of reproducibility because of variations in sample preparation and difficulty in assay development. We have analyzed serum proteins of liver disease patient cohorts by 2D-PAGE and 2D-LC MALDI-TOF MS with respect to expression levels and different isoforms generated by alternative splicing, cleavage by proteases or posttranslational modifications. In clinical proteomics, key issues including sample collection and preparation prior to proteomic analyses or diagnostic assays have been addressed.
1. Depletion of major plasma proteins: The proteins and peptides circulating in serum/plasma are thought to be a source of potential biomarkers for the disease. However, the major plasma proteins abundant in the blood mask the presence of these circulating biomarkers indicative of the disease state, making it difficult to discover such biomarkers in the blood.
2. Evaluation of biomarkers: Several plasma/serum proteins are changed in terms of concentrations and composition with the physiological state of individuals. As accuracy of measurement of biomarker proteins is required, intra-individual deviation should be independent of the methods of sample collection and preparation.
3. Utilization in clinical laboratory: We must standardize the methods of sample collection and storage in routine work at clinical laboratory for detection of protein/peptide biomarkers.
The object of this presentation is to review the methods of sample preparation and storage for serum proteomics and discuss the strategies to improve the detection of proteins in low abundance which have the potential to discriminate between health and disease conditions. A further object is to review those points to consider for the development of clinical assays for proteomic biomarkers.