Amyloid-beta protein 40 (Aβ40)

Amyloid-beta protein 40 (Aβ40) is a 40-amino acid peptide produced by the proteolytic cleavage of the Amyloid Precursor Protein (APP) by beta- and gamma-secretases [7, 13]. It is the most abundant isoform of amyloid-beta in the brain and cerebrospinal fluid, typically found at higher concentrations than the more aggregation-prone Aβ42 [18, 20]. While Aβ40 is less likely to form the initial seeds of amyloid plaques compared to Aβ42, it is a major component of mature plaques and the primary constituent of vascular amyloid deposits in Cerebral Amyloid Angiopathy (CAA) [3, 20]. Biologically, Aβ40 is involved in modulating synaptic transmission, vascular tone, and potentially serving as an antimicrobial agent [7, 18, 20]. In the context of drug development, Aβ40 is a key target for monoclonal antibodies and vaccines aimed at clearing amyloid deposits or neutralizing toxic oligomers [4, 14]. Furthermore, the ratio of Aβ42 to Aβ40 in plasma and CSF serves as a critical biomarker for the early diagnosis of Alzheimer's disease and for monitoring the efficacy of anti-amyloid therapies [1, 6, 9].

Other names

Amyloid-beta peptide 1-40Abeta40A-beta 40Beta-amyloid 40Amyloid beta-protein 40

Monoclonal antibodies bind to soluble or aggregated forms of amyloid-beta to promote clearance via microglia or prevent further aggregation; secretase modulators shift production from longer to shorter isoforms; vaccines elicit an immune response against the peptide.