Fig. 1. ApoE and Aβ transiently co-aggregate en route to fibrils.

A Aβ42 aggregation (4 µM) in the presence of different non-lipidated isoforms of apoE (0 or 80 nM), monitored by ThT fluorescence (n = 3 independent replicates). B Time points at which samples were taken for further analysis. C SiMPull assay for Aβ42 aggregates and apoE-Aβ co-aggregates (1 µM Aβ monomer equivalents), using biotinylated 6E10 antibody for capture, and Alexa-Fluor-647-labeled 6E10 (500 pM) and Alexa-Fluor-488-labeled EPR19392 (1 nM) antibodies for detection. D–F Representative two-color TIRF images of aggregates were captured at t₁ (D), t₂ (E), and t₃ (F). G, H Colocalization between Aβ and apoE at different time points, quantified by aggregate counting (G) and 6E10 fluorescence intensity (H). Data are plotted as the mean and standard deviation of three independent replicates. I Average sizes of colocalized and non-colocalized aggregates (N.B. in diffraction-limited imaging, the minimum apparent aggregate size is ~0.2 µm²). Source data are provided as a Source Data file.