Figure 5.

Effect of apoE on Aβ aggregation. The top panel shows Aβ monomers self-assemble to form small oligomers (O1) that grow to larger oligomers (O2) by monomer addition and/or by clustering. The fibrils (F1) are formed within the large oligomers following nucleation. The fibrils subsequently undergo fragmentation (F1 → F2) and growth (F2 → F3). The bottom panel shows that at low concentrations apoE interacts with the Aβ oligomers (O1 and O2) only, but at higher concentrations, it binds to the fibrils (F1–F3), as well. The broken lines indicate slow growth (L1) and nucleation (L2) of the Aβ oligomers and a reduced rate of fragmentation (L3) of the Aβ fibrils due to interactions with apoE. Stabilization of the oligomers increases the duration of the intermediate phase, while stabilization of the fibrils slows the growth phase.