Innate lymphoid cells and chronic inflammatory skin diseases

Innate lymphoid cells (ILCs) are a newly-discovered family of immune cells in innate immunity. They have no specific antigen receptors (such as T-cell receptors and B-cell receptors) on the surface. Based on the types of secreted cytokines and transduction factors, ILCs can be divided into 3 groups, including ILC1, ILC2 and ILC3, which correspond to Th1, Th2 and Th17 cells respectively. ILCs interact with superficial bacteria and allergens on the mucous membrane and skin by secreting cytokines such as interleukin-5 (IL-5), IL-13, IL-17 and IL-22, and play important roles in homeostasis maintenance and chronic inflammation due to infection, allergy and autoimmunity. Key words: Skin diseases; Inflammation; Lymphocytes; Immunity; Dermatitis, atopic; Psoriasis