The accumulation of amyloid beta protein in the cerebral cortex in Alzheimer's disease (AD) is only one of the outcomes of proteolytic cleavage of amyloid precursor protein (APP). More than 50 different mutations in the APP gene can cause early-onset Alzheimer disease. Cleavage by beta- and gamma-secretase (amyloidogenic pathway) leads to production of amyloid-beta and soluble APP-beta, while cleavage by alpha-secretase (nonamyloidogenic pathway) results in a soluble form of APP, sAPP-alpha. Amyloid-beta proteins that build up in brain parenchyma are mostly produced from APP expressed in neurons, APP695. A different form of APP, APP770, has been detected in cerebrovascular endothelial cells. Amyloid-beta derived from APP770 can accumulate on cerebrovascular walls.
This kit is a solid-phase sandwich ELISA using two antibodies that are highly specific to human APP770 protein; one is precoated on the ELISA plate and the other is HRP-conjugated. This kit can be used to measure human APP770 protein in EDTA plasma, cerebrospinal fluid, or cell culture supernatant.