IL-31, produced mainly by activated CD4+ T cells, is a newly discovered helical cytokine belonging to the gp130/IL6 cytokine family. IL-31 is closely related in structure to IL-6, IL-11, and IL-27. Binding of IL-31 to its receptor activates JAK/STAT, PI3K/AKT, and MAPK pathways. IL-31 acts on a broad range of immune- and non-immune cells and thus possesses potential pleiotropic physiological functions, such as regulating hematopoiesis and immune response. Human IL-31 is also involved in inflammatory bowel disease, airway hypersensitivity, and dermatitis. BioLegend's LEGEND MAX(TM) Human IL-31 ELISA Kit is a sandwich Enzyme-Linked Immunosorbent Assay (ELISA), in which a human IL-31-specific polyclonal antibody is pre-coated on a 96-well strip-well plate. BioLegend's LEGEND MAX(TM) Human IL-31 ELISA Kit is specifically designed for the accurate quantitation of human IL-31 from cell culture supernatant, serum, plasma, or other bodily fluids. It is ready-to-use, accurate, and sensitive.