N-truncated pyroglutamate-modified amyloid-beta (pGlu-Aβ)

N-truncated pyroglutamate-modified amyloid-beta (pGlu-Aβ) is a highly neurotoxic and aggregation-prone variant of the amyloid-beta peptide found in the brains of Alzheimer's disease patients. It is formed through the cyclization of N-terminal glutamate residues at position 3 by the enzyme glutaminyl cyclase, a process that significantly increases the peptide's hydrophobicity and resistance to degradation (Schilling et al., 2008, PMID: 18408755). These biochemical changes allow pGlu-Aβ to act as a potent seed for the rapid accumulation of other amyloid-beta species into insoluble plaques (Nussbaum et al., 2012, PMID: 22553031). Because pGlu-Aβ is found almost exclusively in pathological deposits and not in soluble physiological forms, it represents a highly specific target for immunotherapy. The monoclonal antibody Donanemab was designed to bind specifically to this pyroglutamate epitope, facilitating the clearance of established plaques via microglial-mediated phagocytosis (Mintun et al., 2021, PMID: 33720637). Clinical trials have demonstrated that targeting this specific form of amyloid can lead to robust plaque removal and a significant slowing of clinical decline in patients with early symptomatic Alzheimer's disease.

Other names

AβpE3Pyroglutamate-modified amyloid-betapE3-AβN3pE-AβPyroglutamyl amyloid-beta

Monoclonal antibody-mediated binding to the N-terminal pyroglutamate epitope of amyloid-beta, facilitating microglial phagocytosis and clearance of established insoluble plaques.