ABSTRACT
The proteome is the set of all proteins actually present in a cell or tissue at a given time. The proteome includes all the posttranslational modifications present in mature proteins, which are often required for the proteins to perform their functions. Circulating leukocytes are not the cell type most often used for nutritional research, yet they have advantages for studying proteomes. Leukocytes are sensitive to becoming activated by mitogens and bacterial products, and this activation will induce substantial changes in the proteome. Although many promising gel-free approaches to proteome characterization and comparative analysis are being developed, 2-D gel electrophoresis remains the most used method. Although many interesting new gel-free approaches to proteome studies are being developed, the approach most often used to characterize and compare proteomes is 2-D gel electrophoresis. 2-D gels provide a relatively simple and cost-effective way to characterize and compare expression of over 1000 proteins, as well as detect some of their posttranslational modifications.
