Interleukin-13 (IL-13) is a Th2 cytokine produced by Th2 cells and nuocytes whose biological activities include regulation of gastrointestinal parasite expulsion, allergic inflammation, asthmatic airway hyperresponsiveness, goblet cell hyperplasia, tissue remodeling, and fibrosis. IL-13 also stimulates Arg-1 activity in "alternatively-activated" macrophages. Cayman's IL-13 (mouse) EIA Kit is an immunometric (i.e., sandwich) EIA that permits IL-13 measurements within the range of 0-500 pg/ml, with a limit of detection of 7.8 pg/ml.