Immunopathology of inflammatory bowel disease

Figure 4 Development and classification of innate lymphoid cells[82]. Innate lymphoid cells (ILCs) all derive from an ID2 positive progenitor cell. Group 1 ILCs make interferon (IFN)-γ. Group 2 ILCs produce IL-5 and interleukin (IL)-13. Group 3 ILCs produce IL-17, IL-22, and IFN-γ. NK require IL-15, whereas all other ILCs require IL-7 for development. Group 2 ILCs depend on transcription factors GATA3 and ROR for development. Group 3 ILCs require RORt for development. Also, subsets of group 3 ILCs require additional transcription factors, such as aryl hydrocarbon receptor (AHR) for development. NK cells, which are group 1 ILCs, require both T-bet and eomesodermin (EOMES). The mechanisms of ILC1 development are not fully elucidated, however are known to require transcription factor T-bet for development.