We study how tissue specific immunity is shaped in the digestive system under homeostatic conditions and how it can be perturbed to cause pathologies.
We use a wide range of techniques in mice, including lymph node dissection, microsurgery, lymphatic vessel cannulation, pancreatic islet isolation, multimodal imaging, single cell gene expression analysis, gnotobiotics, and genetic manipulation of mice to model diseases or track immune events. We use a spectrum of gastrointestinal pathogens, and study human material to relate our work to human disease.
Immunological niches in the digestive system
Our goal is to understand what drives niche specific, or local, immunological differences between not only functional segments along the gut, but also the liver-biliary system and the pancreas. We postulate that this immune compartmentalization underlies the nature and site specificity of disease susceptibility, such as pathogen tropisms, food allergies, autoimmune diseases, chronic inflammatory diseases and cancers. Insight into how the immune system is wired in each niche will permit more tailored and potentially effective therapeutic strategies.
Research area I: Driving forces and cellular substrates of tissue-specific lymph nodes in the digestive system
Lymph nodes (LNs) are key sites for the initiation of tissue specific adaptive immunity. Along the gastrointestinal tract they are immunologically distinct (Esterhazy et al., Nature 2019), with the more proximal LNs being more tolerance-promoting and the more distal LNs more pro-inflammatory- but we wonder how extensive this paradigm is, what developmental, cellular and molecular forces underlie it, and how hardwired a LN tone is or if it can be re-established after a perturbation.
Projects in the lab to address these questions include studying the active role of the gut tissue lymphatics and the lymph they carry, LN macrophages, and LN stromal cell in shaping LN niches.
Research area II: Immune crosstalk between the gut, pancreas, and liver
While the gut, pancreas, and liver are distinct organs, they are directly connected through shared LNs, vascular supply and ductal systems, such as the biliary and pancreatic ducts. This is due to their common developmental origin, and serves both metabolic and immunological co-ordination in response to common exposures. However, all three routes also offer unique modes of immune-modulation of one organ through more or less direct interaction with another branch of the digestive system. The extent of such reciprocal control of tissue-specific innate and adaptive immunity is our subject of investigation, with a particular focus on the impact on the pancreas and the implications for the etiology and control of pancreatic diseases such as type 1 and type 2 diabetes, pancreatitis, and pancreatic ductal adenocarcinoma.