The accumulation of amyloid-beta protein in the cerebral cortex in Alzheimer's disease (AD) is only one of the outcomes of the proteolytic cleavage of amyloid precursor protein (APP). Cleavage by beta- and gamma-secretase (in the amyloidogenic pathway) leads to production of amyloid beta and soluble APP-beta (sAPP-beta), while cleavage by alpha-secretase (in the nonamyloidogenic pathway) results in another soluble form of APP, sAPP-alpha. Several mutations in the sAPP gene can give rise to variants of both sAPP-alpha and sAPP-beta, and more than 50 different mutations in the APP gene can cause early-onset Alzheimer’s disease.
A double missense mutation (Lys670→Asn and Met671→Leu) in APP found in a Swedish pedigree (APP-beta-sw) elevates Aβ40 and Aβ42 production, and the mutation is utilized in establishment of transgenic mice overexpressing a mutant form of human amyloid precursor protein. Amyloid beta production and beta-secretase cleavage of APP-beta-sw reportedly occur in the endoplasmic reticulum, Golgi, and endocytic compartments.
ELISAs for sAPP Detection
These kits are solid-phase sandwich ELISAs using two highly specific antibodies to sAPP variants; one is precoated on the ELISA plate and the other is HRP-conjugated. The human sAPP ELISA kit can be used to measure human sAPP variants in serum, EDTA plasma, cerebrospinal fluids, or cell culture supernatant. The rodent sAPP-alpha ELISA kit can be used to measure mouse or rat sAPP-alpha as well as full-length APP in serum, EDTA plasma, cell culture supernatant, and brain extract samples.
Antibodies for sAPP Detection
These antibody products are affinity-purified IgG antibodies that recognize the C-terminus of human soluble APP-alpha (Cat. #11088) and soluble APP-beta-Swedish (sAPP-beta-sw) (Cat. #10321). The APP Antibody products are raised in mouse using synthetic peptides and can be applied to Western blot (WB) and immunohistochemical (IHC) detection (Cat. #10321 only) as well as immunoprecipitation (IP) (Cat. #11088 only) of human sAPP-alpha and sAPP-beta-sw. The sAPP-beta antibody is an affinity-purified rabbit IgG antibody that recognizes wild-type (w) human soluble APP-beta protein. The sAPP-beta antibody is raised in rabbit using a synthetic peptide and can be applied to Western blot (WB) or immunoprecipitation (IP) of human sAPP-beta.