Aggregates of β-Amyloid Peptide (Aβ Aggregates)

Aggregates of β-amyloid peptide (Aβ) are assemblies formed by the self-association of amyloid beta peptides, which are 36–43 amino acid residues in length. These aggregates are a hallmark of Alzheimer's disease and other neurodegenerative disorders, where they accumulate as extracellular plaques in the brain. The most common forms involved in aggregation are Aβ40, Aβ42, and to a lesser extent Aβ43. Aggregated forms—especially soluble oligomers—are considered highly neurotoxic and central to Alzheimer's disease pathogenesis due to their ability to disrupt cellular function and induce neuronal death. Mature fibrillar aggregates constitute the core component of amyloid plaques observed histopathologically. A variety of cell surface receptors recognize aggregated Aβ, including scavenger receptors (SCARA1, MARCO, SCARB1), RAGE (receptor for advanced glycation end products), G-protein coupled receptors (FPR2), Chemokine-like receptor (CMKLR1), Toll-like receptors (TLR2/TLR4 with co-receptor CD14). These mediate microglial activation/inflammation or promote phagocytosis/clearance. Some such as CD33 may accelerate accumulation by inhibiting clearance mechanisms.

Other names

Amyloid beta aggregatesAβ aggregates

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