【项目简介】
Interleukin-18 (IL-18, also known as interferon-gamma inducing factor) is a proinflammatory cytokine that belongs to the IL-1 superfamily and is produced by macrophages and other cells. This cytokine can induce the IFN-gamma production of T cells. The combination of IL-18 and IL12 has been shown to inhibit IL4 dependent IgE and IgG1 production, and enhance IgG2a production of B cells. IL-18 binding protein (IL18BP) can specifically interact with this cytokine, and thus negatively regulate its biological activity. IL-18 is an IL-1−like cytokine that requires cleavage with caspase-1 to become active, was found to increase IgE production in a CD4+ T cells-, IL-4− and STAT6−dependent fashion. IL-18 and T cell receptor−mediated stimulation could induce naïve CD4+ T cells to develop into IL-4−producing cells in vitro. Thus, caspase-1 and IL-18 may be critical in regulation of IgE production in vivo, providing a potential therapeutic target for allergic disorders. IL-18 production in primary synovial cultures and purified synovial fibroblasts was, in turn, upregulated by TNF-α and IL-1β, suggesting that monokine expression can feed back to promote Th1 cell development in synovial membrane.
 
【检验原理】
本试剂盒采用双抗体夹心ELISA法。酶标微孔板上预包被有抗小鼠IL-18抗体，当加入标准品和待测样本时，标准品和待测样本中的小鼠IL-18会和该抗体结合。洗板后，游离的其他成分被洗去，加入辣根过氧化物酶标记的的抗小鼠IL-18抗体可与被酶标板捕获的小鼠IL-18结合，形成“包被抗小鼠IL-18抗体+小鼠IL-18+抗小鼠IL-18抗体-HRP”免疫复合物。当加入TMB显色底物后，复合物上连接的HRP催化底物反应，生成蓝色产物，终止反应后变为黄色。在450nm处测定OD值，小鼠IL-18浓度与OD450值之间呈正比，可通过绘制标准曲线求出标本中小鼠IL-18的浓度。