has part innate lymphoid cell group 3 innate lymphoid cell 2017-01-31T20:21:26Z https://cellxgene.cziscience.com/cellguide/CL_0001071 ILC3 Group 3 innate lymphoid cells (ILC3) belong to the family of innate lymphoid cells. They share a high degree of similarity with T lymphocytes, particularly in terms of their transcriptional program and their cytokine production profiles, but lack the antigen-specific receptors that characterize adaptive immune cells. Originating from common lymphoid progenitors, ILC3s are typically found in mucosal tissues and are especially prevalent in the gastrointestinal tract. The grouping of ILC3s originally included lymphoid tissue inducer (LTi) cells, which have more recently been categorized separately. ILC3s play an important homeostatic role in the gastrointestinal tract, contributing to mucosal barrier integrity, lymphoid organogenesis, and controlling the balance between tolerance and immunity to commensal and pathogenic bacteria, respectively. The protective role of ILC3s primarily stems from their capacity to respond to signals of microbial invasion or tissue damage, releasing an array of cytokines such as Interleukin-22 (IL-22) and Interleukin-17 (IL-17) which are dependent upon the RORγt transcription factor. These cytokines in turn mediate protective responses including the enhancement of epithelial barrier function, the promotion of tissue repair, and the control of bacterial infection. However, ILC3s can also contribute to the development of inflammatory diseases such as inflammatory bowel disease (IBD) and psoriasis. Therefore, studies have also emphasized the importance of regulatory mechanisms controlling ILC3 activation, providing novel insights into the complexity of immune regulation in maintaining tissue homeostasis. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) An innate lymphoid cell that constituitively expresses RORgt and is capable of expressing IL17A and/or IL-22. nuclear receptor ROR-gamma isoform 2