Goat Anti-Human APP (C-terminal) polyclonal antibody for ELISA, IHC, WB. The amyloid precursor protein (APP) is a large membrane protein whose C-terminus projects into the extracellular space. In Alzheimer`s disease (AD), the APP is proteolytically cleaved at the N-terminal of A? by ?-secretase (BACE) to release a ~100 kD APPs? protein into the extracellular space. The remaining 12 kD fragment remains membrane bound where it can be cleaved at its C-terminus by ?-secretase (presenilins) to release the insoluble A? peptide into the extracellular space with the ~8 kD APP C-terminal fragment (CTF?) remaining membrane bound. The APP is the subject of intensive investigations to determine how this protein is broken down abnormally in AD brains to give rise to A?, which is present in senile plaques and vessels.