ABSTRACT: The principal objective of the Biophysical Imaging Core is to provide PPG investigators with a complete range of expertise, training, equipment, and data analysis tools to obtain nano-to-micro scale biophysical information pertaining to the cellular and molecular basis of endothelial cell (EC) cytoskeletal rearrangements and barrier regulation. Core D personnel and equipment will allow PPG scientists to image 3D structures, evaluate physi- cal and chemical properties and define perturbant-induced real-time changes in the structures and activity of cells and subcellular constituents, including membranes, cytoskeletal networks, cell-matrix and cell-cell junc- tions. This Biophysical Imaging Core supports the PPG's four research projects with quantitative microscopy related to atomic force microscopy (AFM), confocal and deconvolution fluorescence microscopy, total internal reflection fluorescence (TIRF) microscopy, dynamic (live) fluorescence imaging, mechanical measurements of cells (traction force microscopy), super-resolution microscopy and automated high-throughput quantitative mi- croscopy to allow observation of cellular organelles (e.g., cortical cytoskeleton, junctional complexes, focal ad- hesions and lamellipodia) in great detail (3D). Core D will also interact with each Project and with Core B (Ge- nomic/Genetic and Proteome Core) to culture endothelial cells engineered to express different nmMLCK1/2, cortactin, NAMPT, TLR4, DOCK1, lamellipodin, integrin β4, kindlin-2, PSGL1, P-Selectin and S1PR1/3 recep- tors transgenes with specific SNP or post-translational modification mutations and measure various biophysical forces (TFM and AFM). The Core also offers access to experienced use of the complete resources of the Uni- versity of Arizona Imaging Core Facilities that includes state-of-the-art high-resolution fluorescence microscopy systems. This Core will also make use of the common resources available at Arizona Research Laboratories. The Biophysical Imaging Core, led by Carol C. Gregorio, PhD, includes personnel and laboratory facilities for a wide range dynamic fluorescence imaging, fabrication, and mechanobiophysics. Core D personnel have pro- fessional experience spanning the fields of high-resolution imaging and examining physical and chemical properties, including mechanobiophysics, and various scanning probe microscopies. All Core D experiments will be conducted at the University of Arizona in Tucson.