This proposal, if funded, will make possible an upgrade of our Becton Dickinson FACSVantage SE flow cytometer to include DiVa electronics, TurboSort, and the replacement of fifteen-year old lasers. The projects included in this application are being conducted with faculty in five departments within the University of South Alabama (USA) College of Medicine (COM) including the Departments of Microbiology/Immunology, Biochemistry and Molecular Biology, Cell Biology and Neuroscience, Pharmacology and Medicine, as well as the USA Cancer Research Institute, the Center for Lung Biology and the Sickle Cell Center. Nine of the projects involve NIH-funded investigators. The technology and reliability represented by this upgrade are required in the following areas of research in the USA COM: 1) repair of DNA induced by environmental agents, 2) the role of immature laminin receptor protein (iLRP) in tumor development and immune cell activation, 3) prostate epithelial cell-specific gene regulation, 4) regulation of cell cycle progression by ser/thr protein phosphatases, 5) antibody-mediated protection against herpes stromal keratitis and the role of chemokines in corneal inflammation, 6) cellular signaling in lymphocytes from New World primates, 7) metastasis-related antigen expression on human cancer cells and mechanisms of tumor cell sensitivity to therapy, 8) the reversal of inheritable mitochondrial disorders, NARP (neuropathy, ataxia, retinitis pigmentosa) and MILS (maternally inherited Leigh Syndrome), 9) role of ornithine decarboxylase in the endothelial cell toxin, monocrotaline, 10) role of activated leukocyte cell adhesion molecule and activated monocytes in the pathogenesis of acute chest pain, 11) role of erythrocyte-endothelial cell adhesion in acute lung injury in sickle cell disease, 12) chrondrocyte viability in osteochondrial tissue transfer, 13) acute lung injury in sickle cell disease and the role of erythrocyte-endothelial cell adhesion, 14) studies on metastasis-related antigen expression on human cancer cells, and 15) studies in immunotherapy in cancer patients. There has been an increasing awareness on the part of our NIH-funded investigators to require sort rates faster than those available with our Vantage SE as it is now configured. In addition, the lasers purchased with our FACS 440 in 1988, and transferred to the Vantage SE in 1998, are approaching the end of their useful lifespan as repairs becoming increasingly expensive and parts scarce. Four-way sorting (and increased) sort yields through the elimination of electronic dead-time), post acquisition compensation, greater flexibility with regard to signal triggering, and better data resolution, which are features of the DiVa option, will benefit all the members of our user group. ? ?