【项目简介】
Brorin (brain specific chordinlike protein), also called VWC2, is an ~46 kDa glycoprotein that is a member of the Chordin family of secreted BMP regulators.The human Brorin cDNA encodes 325 amino acids (aa) including a 27 aa signal sequence and a 298 aa secreted mature protein with two VWFC (von Willebrand factor C) domains. These domains contain a pattern of 10 cysteine residues that is conserved in other family members, with the remaining aa sequence sharing little identity . Human Brorin shares 90%, 91% and 95% aa sequence identity with mouse, rat and equine Brorin, respectively. It also shares aa identity with VWC2L (Brorinlike) of 37% overall and 62% within the VWFC domains . The human XPNPEP2 gene encodes VWC2 (APP2), which is also known as Xprolyl Aminopeptidase 2 or membrane bound Aminopeptidase P . Human APP2 is widely expressed in many adult tissues with the highest levels in the kidney . 

【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VWC2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VWC2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VWC2抗体可与被酶标板捕获的人VWC2结合，形成“包被抗人VWC2抗体+人VWC2+抗人VWC2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VWC2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VWC2的浓度。