【项目简介】
Kininogen, also known as α2-thiol proteinase inhibitor, is a multi-function protein. There are two alternatively spliced forms, designated as the high molecular weight (HMW) and low MW (LMW) forms (1). The HMW form is synthesized as a 644 amino acid residue precursor with a signal peptide (residues 1-18). The mature chain (residues 19-644) is further processed into the heavy (residues 19-380) and the light (residues 390-644) chains. The active peptide bradykinin (residues 381-389) is released, which has a variety of functions including muscle contraction, hypotension and inflammation. The heavy chain consists of three cystatin-like domains, which are responsible for inhibiting cysteine proteases. The light chain consists of a His-rich domain, which is associated with the clotting activity. In comparison to the HMW form, the LMW Kininogen (427 residues) has the same sequence in its heavy chain and bradykinin, but a different sequence in its light chain (residues 402-427). The LMW form is not involved in blood clotting.
 
【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人KNG1抗体，当加入标准品和待测样本时，标准品和待测样本中的人KNG1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人KNG1抗体可与被酶标板捕获的人KNG1结合，形成“包被抗人KNG1抗体+人KNG1+抗人KNG1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，人KNG1浓度与OD450值之间呈正比，可通过绘制标准曲线求出标本中人KNG1的浓度。