Amyloid-β Antibodies

Amyloid‑β (Aβ) peptides, particularly the aggregation‑prone Aβ 1-42 isoform, are central to Alzheimer’s disease (AD) pathology. As amyloid accumulates, CSF Aβ 1-42 levels decrease due to deposition into amyloid plaques, but the Aβ42/40 ratio is a more reliable indicator of amyloid pathology because it corrects for inter-individual differences in total Aβ production and technical variability rather than reflecting sequestration alone¹. For both Elecsys and Lumipulse the p-tau/Aβ1- 42, Aβ1- 42/Aβ1- 40, and t-tau/Aβ1- 42 ratios showed similarly good concordance with amyloid PET (Elecsys: 93,90,90%; Lumipulse: 94,92,90%) and were higher than Aβ1- 42 alone (Elecsys 85%; Lumipulse 84%)^2,3. Multiple studies show that combining pTau 217 with amyloid measures, especially through the ratio of pTau 217/Aβ 1-42 or the combination of pTau 217 with the Aβ 1-42/1-40 ratio, further improves diagnostic accuracy for detecting amyloid positivity and early AD^4,5.

The ADx101, ADx102 and ADx103 monoclonal antibodies support immunoassay development for quantifying Amyloid‑β isoforms.