Research Abstracts Online
January - December 2011
University of Minnesota Twin Cities
PI: Troy C. Lund
Proteomic Interrogations Into MSC
The identification of cell markers remains an elusive process. There are many new proteomic-based methods being developed. This researcher has used one such method, iTRAQ, to evaluate differentially expressed proteins from mesenchymal stem cells that were differentiated into adipocytes and osteoblasts as well as retained in an undifferentiated state. Serial MS/MS analysis on the lysates determined the maximal number of identifiable of proteins. 742 proteins in total were identified (10% local protein-level false discovery rate) and these proteins were grouped for gene ontogeny analysis. Proteins with the most extreme relative abundance ratios in either differentiated state were examined and their relative expression confirmed by immunoblot. In almost every case the iTRAQ relative expression levels were confirmed by immunoblot. The ability to quickly and quantitatively assay the proteome of mesenchymal stem cells will lead to more repaid identification of cell markers important in differentiation. In addition, the ability to mark undifferentiated cells may provide a more thorough understanding of the molecular processes governing this increasingly popular stem cell type.