【项目简介】
SAA4 is a member of the SAA family.SAA proteins are family of apolipoproteins of high density lipoprotein (HDL). They can be separated into two distinct groups. First group (SAA1, SAA2, and SAA3) consists of acute phase reactant whose expression level increase in the blood in a response to trauma, infection, inflammation, and neoplasia. These acute phase SAAs associates with HDL during inflammation and remodel the HDL particle by displacing Apo-A1. The second distinct group consists of SAA4 and SAA5 which exist as the minor apolipoproteins on HDL, but this group of SAA constitutes more than 90% of all the SAA during homeostasis, and it is thought to play a role in the normal functioning of the HDL particle. SAA4 is a constitutively expressed protein which expressed only in humans and mice.It is connected almost completely with lipoproteins of the high density range. The physiological function of SAA4 is unknown, and its serum concentration has no association with those of other major apolipoproteins.

【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SAA4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SAA4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SAA4抗体可与被酶标板捕获的人SAA4结合，形成“包被抗人SAA4抗体+人SAA4+抗人SAA4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SAA4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SAA4的浓度。