PROJECT SUMMARY Metabolic and inflammatory disorders such as autoimmune and neurodegenerative diseases are increasing at alarming rates. Many of these are not tissue-specific occurrences but complex and often overlapping pathologies of unknown origin for which no cure exists. Examples are concurring pathologies of the gut-liver axis, such as inflammatory bowel disease and inflammatory pathologies of the liver. The discovery of “unconventional” T lymphocytes and their ability to respond to non-peptide antigens, marks a new area in the exploration of how migratory cells and immunometabolic networks shape the emergence of autoimmune and metabolic diseases. These are comprised of a heterogeneous group of lymphocytes, such as mucosa-associated invariant T cells, whose invariant TCR can recognize cellular and microbial metabolites via presentation through the MHC-like receptor 1 (MR1). Emerging evidence suggest MR1-restricted T cells to be implicated in a wide variety of disorders ranging from ulcerative colitis to type 1 diabetes, autoimmune hepatitis and multiple sclerosis via TCR-specific and non-specific means. However, lack of models relevant to human physiology represents a significant hurdle in our understanding of how MR1-restricted T cells affect the host and diseases. We have developed an approach that utilizes multiorgan human microphysiological models (MOMPS) of donor-matched tissues and unbiased systems biology tools to gain granular insight into causal relationships between cellular crosstalk and immunometabolic illnesses. In order to gain critical knowledge about the heterogeneity and functionality of MR1-restricted lymphocytes, we will combine single-cell characterization of human MR1-restricted T cells across donor-matched tissues and circulation, with mechanistic studies in a microphysiological model of the gut-liver axis. These MOMPS will be used to systematically search for causal relationships between MR1-restricted lymphocytes, tissues, and external factors by reconstructing donor tissue at various levels of complexity. Each level will be challenged via predetermined inflammatory and metabolic perturbations. Multiomic observation of changes based on interaction and perturbation at each degree of complexity will allow us to construct interaction networks that reveal causal relationships among entities. With computational tools and resolution into molecular underpinnings of cellular and tissue homeostasis, MOMPS represent a unique opportunity to systematically dissect how interactions at a lower order inform new behavior at the macro scale within and between organ systems. While the gut-liver axis will serve as a model in this proposal, the developed approach, together with fundamental biological insights into MR1 expression by parenchymal tissue and function of MR1-restricted T cells, will be applicable to other organ systems and a variety of pathologies. Our overarching goal is to identify tangible targets and new cell-based appro...