In the past few years, an emerging group of innate lymphoid cells (ILCs) has been identified in mucosa I tissues. ILCs are found close to epithelial barriers, where they constitute a major source of the homeostatic cytokine interleukin 22. ILC cytokine profiles resemble those produced by helper T cells, yet they lack antigen specificity and provide a quicker immune response. Recent studies brought to light a previously unappreciated role of ILCs in protecting against enteric pathogens and promoting homeostasis in mucosal tissues. However, the role of ILCs in tissue damage in the absence of pathogenic infections remains unknown. This thesis aims to investigate the contribution of type 3 innate lymphoid cells (ILC3) in intestinal epithelial damage responses. Activation mechanisms and effector functions of ILC3 will be discussed in the context of intestinal damage.