PROJECT SUMMARY / ABSTRACT UC Davis is the academic home of the California National Primate Research Center, an NIH-supported resource for investigators nationwide. The Primate Center includes experienced Core Scientists that have established cutting-edge research programs, and provide expertise, services, and training to the greater research community. The Primate Center supports a broad program of research and has an outstanding record of scientific achievements. UC Davis also has major strengths in translational research and animal models including nonhuman primates for the preclinical study of human health and disease, and strongly supports in vivo imaging as applied across the translational and clinical spectrum. The goal of this application is to obtain a replacement system for the current primate total-body Positron Emission Tomography (PET) miniEXPLORER prototype that is dedicated solely for use in translational studies with nonhuman primates. The current system is housed within the Primate Center Multimodal Imaging Core, and with all of the essential infrastructure required for nonhuman primates including space, expertise, support, security, biosafety, and knowledge to oversee and conduct studies with nonhuman primates. The Multimodal Imaging Core is widely publicized through established informational websites including the Primate Center and UC Davis Clinical and Translational Science Center, as well as other campus and national entities, and routinely provides services to investigators locally, regionally, and nationally. The total-body PET prototype is currently in active use and is not sustainable thus a replacement primate miniEXPLORER-II total-body PET system is requested. Many NIH- funded studies currently in progress, identified for funding, and planned benefit substantially from the primate miniEXPLORER prototype in active use. These studies span regenerative medicine and gene therapy, somatic cell genome editing, investigations focused on maternal/placental/fetal interactions and pregnancy-related disorders, cardiovascular disease, infectious diseases, cancer, and neurodevelopmental disorders. The requested primate miniEXPLORER-II total-body PET imaging system is essential for these ongoing studies with NIH-funded investigators and in order to meet their research goals and objectives. This replacement will ensure substantial benefits for currently funded and new investigators and the ongoing growth of highly innovative and transformative NIH-funded research, permit the conduct of investigational new drug (IND)- enabling studies necessary to advance to human clinical trials, and expand existing capabilities for investigators addressing a range of critical questions focused on human health and disease, from the earliest developmental stages to aging populations.