CYTOMICS: AN ENTRY TO BIOMEDICAL CELL SYSTEMS BIOLOGY Cytomics Goes 3D: Toward Tissomics

CYTOMICS AND MICROSCOPY Conducting a Human Cytome Project will require stateof-the-art techniques and technologies in different fields. Methods arising from molecular biology (genome level) and protein chemistry (proteome level) will be necessary but not sufficient for this project. Although the cytome contains the genome and the proteome, the cytome level comprises additional and essential information. The art of combining molecular, morphologic, and phenotypic information at the single-cell level and at the biological locus where cellular dysfunction appears and formation of disorders takes place—an art known as microscopy—represents the key framework of methods for scrutinizing the cytome (1,2). Although two high-throughput and high-content methods are currently at hand for multiparametric and multicolor cell analysis, i.e., flow and image cytometry, spatial relations and the molecular morphology of cells and tissues are accessible only to microscopic analysis (3–5). In a cytomics context, multiparameter fluorescence methods and hyperchromatic staining are of particular interest because they permit the sequential analysis of DNA status, protein expression and protein interaction, cellular distribution, and morphologic characteristics (6,7).