【项目简介】
Polymeric immunoglobulin receptor, also known as PIGR, is a member of the immunoglobulin superfamily and a Fc receptor. The ectodomain of this receptor consists of five units with homology to the variable units of immunoglobulins and a transmembrane region, which also has some homology to certain immunoglobulin variable regions. PIGR is expressed on several glandular epithelia including those of liver and breast. The deduced amino-acid sequence has a length of 764 residues and shows an overall similarity of 56% and 64% with the rabbit and rat counterpart. PIGR mediates transcellular transport of polymeric immunoglobulin molecules, and thus facilitates the secretion of IgA and IgM. During this process, a cleavage occurs that separates the extracellular (known as the secretory component) from the transmembrane segment of PIGR.
 
【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PIGR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PIGR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PIGR抗体可与被酶标板捕获的小鼠PIGR结合，形成“包被抗小鼠PIGR抗体+小鼠PIGR+抗小鼠PIGR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PIGR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PIGR的浓度。