PROJECT SUMMARY_CORE C Core C Preclinical Tumor Imaging will provide services and expertise to all PPG investigators in designing and executing imaging experiments required to meet the objectives of each project. Core personnel will: 1) assist with design and execute imaging experiments; 2) store, process, and distribute as needed, all tissues required for downstream analysis, or use in other projects; 3) assist or directly perform all animal imaging experiments needed; 4) assist or directly perform all animal and imaging data analyses and interpretation; and 5) facilitate archiving and retrieval of data. Investigators will be advised of the full potential of Core C capabilities to ensure that experimental designs fully utilize available services. Preclinical tumor imaging capabilities available include Single Photon Emission Computed Tomography combined with X-ray CT (SPECT-CT) for whole-body imaging, intravital microscopy (IVM) and static microscopy imaging. Each of our imaging modalities described is well- suited to focus on a specific aspect of antibody targeting and processing. The multiple imaging approaches provided by Core C will complement and confirm one another, and will provide a more complete analysis of targeting, delivery and processing in vivo at multiple levels. Data acquired will assist in: 1) validating AnnA1 expression by examining tissue sections using histochemical and fluorescence based assays; 2) defining and quantifying tumor targeting by hAnnA1 antibodies over time using dynamic whole-body imaging; and 3) evaluating and quantifying EC processing of hAnnA1 targeted immunocomplexes and conjugates via dynamic IVM in novel human tumor models. Core C services will help answer key questions on the distribution of AnnA1 in human tissues, on how tumors process specific probes in vivo, and how caveolae function in the tumor vascular endothelium. Data from preclinical image analysis will be used to assess the effectiveness of drugs and imaging agents for development in Projects 1 and 2, and eventual clinical utility in Project 3.