Unveiling the mystery of ILC3s: Their functions and interactions in mucosal immunity

Innate lymphoid cells (ILCs) are a recently discovered subset of immune cells that play a crucial role in preserving tissue health and combating infections. Among these, ILC3s are particularly vital in regulating mucosal immunity across multiple organs such as the gut, lungs, and skin. The purpose of this article is to present a comprehensive and detailed overview of current knowledge on ILC3s, with a specific emphasis on their intricate interactions with various components of the intestinal microenvironment. Recent research on the complex, bidirectional communication pathways between ILC3s and intestinal epithelial cells, stromal cells, immune cells, microbiota, their metabolites, and diet are highlighted. Furthermore, this review comprehensively examines the diverse functions of ILC3s, which include lymphoid tissue development, tissue repair, infection, inflammation, and metabolic diseases, as well as the effector molecules that facilitate these functions. Overall, this review provides valuable insights into the biological and functional aspects of ILC3s and underscores their potential for developing innovative therapies for immune-mediated disorders, while also acknowledging the remaining knowledge gaps and challenges that need to be addressed.