FIGURE 3.

Biogenesis of types 1 and 2 Aβ oligomers in the brain. Adapted, with permission, from Liu et al., “Quaternary structure defines a large class of Aβ oligomers neutralized by sequestration” Cell Reports, 2015. Type 1 oligomers form by primary nucleation, do not have basic the structural feature of amyloid fibrils (ie, do not contain in‐register β‐sheets), are not concentrated around amyloid plaque cores, and appear before amyloid plaques. ²⁴ Aβ*56 ¹⁰ is a type 1 oligomer. ²⁴ Type 2 oligomers form by secondary nucleation, contain in‐register β‐sheet structure, are concentrated around amyloid plaque cores, and appear after amyloid plaques. ²⁴ Both types of oligomers affect neuronal signaling pathways through interactions with dendritic spines