Pyroglutamate-3 amyloid-beta peptide (pGlu3-Aβ) (pGlu3-Aβ)

Pyroglutamate-3 amyloid-beta (pGlu3-Aβ) is a highly neurotoxic, N-terminally truncated variant of the amyloid-beta peptide that plays a critical role in the pathogenesis of Alzheimer's disease (PubMed: 22103223). It is formed when the N-terminal glutamate of truncated Aβ(3-40/42) is cyclized by the enzyme glutaminyl cyclase, creating a pyroglutamate residue that enhances the peptide's hydrophobicity and resistance to proteolytic degradation (PubMed: 15514643). This modification promotes rapid aggregation and the formation of stable, toxic oligomers that seed the accumulation of larger amyloid plaques (PubMed: 21566150). Because pGlu3-Aβ is predominantly found in pathological deposits rather than in healthy brain tissue, it serves as a highly specific target for immunotherapy (AlzForum: Donanemab). Therapeutic agents such as donanemab are monoclonal antibodies designed to bind this specific epitope, facilitating the clearance of existing plaques through microglial-mediated phagocytosis (NEJM: 10.1056/NEJMoa2100708). By targeting this modified form, researchers aim to reduce the overall amyloid burden and slow cognitive decline in affected patients (Nature Medicine: 10.1038/s41591-021-01355-1).

Other names

AβpE3pE3-AβN-terminal truncated amyloid-betaPyroglutamyl-3 amyloid-betaAbeta pE3

Monoclonal antibodies bind specifically to the N-terminal pyroglutamate epitope of truncated amyloid-beta, facilitating microglial-mediated clearance of existing amyloid plaques via Fc-receptor interaction (PubMed: 33720637).