PROJECT SUMMARY: MICROSCOPY AND MICROFLUIDICS CORE The objective of the C-SiG Microscopy and Microfluidics Core (MMC) is to be a user-friendly resource that connects investigators with state-of-the-art, optical and microfluidics technologies and services. Under the direction of Dr. Mark McNiven, an accomplished cell biologist, and Dr. Alexander Revzin an experienced biomedical engineer, the Core integrates existing resources with new equipment added during this funding cycle (Zeiss LSM980 + Airyscan 2 and Nikon AXR confocal systems and microfluidic devices). This Core also collaboratively partners with the Institution-wide Mayo Microscopy and Cell Analysis Core to enhance resources available to center members by providing GI-relevant expertise and training for C- SiG members. The Specific Aims of this core are three-fold. First, to provide reliable, accessible, state-of-the- art microscopy and microfluidics technologies to C-SiG members to facilitate their study of GI cellular signaling cascades. Second, to provide education, technical advice, guidance, and feedback on experimental design and results for both basic and sophisticated cellular imaging and microfluidics methods. Emphasis is placed on providing technical instruction as well as educating faculty on how such approaches can expand the scope and breadth of their scientific programs. Third, to work collaboratively with C-SiG members to develop proficiency in the use of cutting-edge optical imaging and microfluidics technologies that offer new capabilities for assessing cell signaling. The most popular Core service is access to the well-maintained C-SiG Microscopes (> 37,600 hours total during the past 5 years). The Core also provides consults, training, technical advice, and development of novel, innovative optical and microfluidics approaches to the study of signaling pathways in GI cells and tissues. Consults and training cover a wide range of topics including: confocal, histology, live cell, total internal reflection fluorescence (TIRF) microscopy, and super- resolution microscopy; microfluidics device design and applications; expression and use of fluorescence-based bioprobes that facilitate the study and localization of specific signaling molecules including both proteins and lipids; cell/tissue computer morphometry; high resolution real-time imaging of live cells, and data analysis. In addition, the Core now provides full-service microfluidics support including device design, fabrication, and execution of microfluidics experiments for C-SiG members. Since September 2019, when we began piloting microfluidics services within this core, the core has provided 17 C-SiG members with 692 microfluidics devices, including those developed for spheroid/organoid culture, organotypic cultures, paracrine and juxtacrine co-cultures, and neuro-epithelial co-cultures. Over the past 5 years, the C-SiG Microscopy and Microfluidics Core has provided services to 66% of current membership and supported 1...