RESUMEN
The intestine hosts the largest immune cell compartment in the body as a result of its continuous exposure to exogenous antigens. The intestinal barrier is formed by a single layer of epithelial cells which separate immune cells from the gut lumen. Bidirectional interactions between the epithelium and the immune compartment are critical for maintaining intestinal homeostasis by limiting infection, preventing excessive immune activation, and promoting tissue repair processes. However, our understanding of epithelial-immune interactions incomplete as the complexity of in vivo models can hinder mechanistic studies, cell culture models lack the cellular heterogeneity of the intestine and when established from primary cell can be difficult to maintain. In the last decade, organoids have emerged as a reliable model of the intestine, recapitulating key cellular and architectural features of native tissues. Herein, we provide an overview of how intestinal organoids are being co-cultured with immune cells leading to substantial advances in our understanding of immune-epithelial interactions in the gut. This has enabled new discoveries of the immune contribution to epithelial maintenance and regeneration both in homeostasis and in disease such as chronic inflammation, infection and cancer. Organoids can additionally be used to generate immune cells with a tissue-specific phenotype and to investigate the impact of disease associated risk genes on the intestinal immune environment. Accordingly, this review demonstrates the multitude of applications for intestinal organoids in immunological research and their potential for translational approaches.
RESUMEN
PURPOSE OF REVIEW: Recognition of the importance of innate lymphoid cells (ILCs) in the immune mechanisms of food allergy has grown in recent years. This review summarizes recent findings of ILCs in immunoglobulin E (IgE)-mediated food allergy. New research on ILCs in the context of the microbiome and other atopic diseases are also considered with respect to how they can inform understanding of the role of ILCs in food allergy. RECENT FINDINGS: ILCs can mediate allergic and tolerogenic responses through multiple pathways. A novel subset of interleukin (IL)-10 producing ILC2s are associated with tolerance following immunotherapy to grass pollen, house dust mite allergy and lipid transfer protein allergy. ILC2s can drive food allergen-specific T cell responses in an antigen-specific manner. A memory subset of ILC2s has been identified through studies of other atopic diseases and is associated with effectiveness of response to therapy. SUMMARY: The role of ILCs in food allergy and oral tolerance is relatively understudied compared to other diseases. ILCs can modulate immune responses through several mechanisms, and it is likely that these are of importance in the context of food allergy. Better understanding of theses pathways may help to answer fundamental questions regarding the development of food allergy and lead to novel therapeutic targets and treatment.