Core B – Summary Core B will utilize the improvements developed for the 3D intestinal systems to support the preparation and utility of the tissue models, including generating the scaffolds and seeded scaffolds/tissues for all projects. The plans are based on our extensive preliminary data where we have demonstrated structurally- and functionally- relevant 3D human intestinal tissues for the study of infectious diseases. The intestinal systems include enteroid primary cell sources, a 3D porous protein scaffolding system with a geometrically-engineered hollow lumen with adaptability to both large and small intestinal tissues. In Aim #1 the focus will be on the preparation of scaffolds and 3D intestinal systems for the three research projects. Here the goal is to provide intestinal tissues to support the three research projects (60 systems per week), obtain primary tissue samples from the clinic, establish early passage organoid material from both the small intestine and the colon, and train individuals in the various projects. In addition, a focus will be on documenting all materials for validation and quality control to assure reproducibility. In Aim #2 the focus will be on optimization of the 3D intestinal tissues. Here the goal is to continue to optimize the currently developed 3D human intestinal tissues generated from organoids for physiological relevance, and develop increasingly complex features to facilitate analysis of intestinal pathogens. These activities will include the incorporation of additional cell types, supplementation of the scaffolds with ECM components, and further development of a bioreactor system to control flow, peristalsis and oxygen levels. A team of faculty, post doctoral fellows and a technician will support the needs of Core B and work closely with the research teams on all phases of the plans.