C1213 and CNI-1493 change Aβ 1-42 aggregation in vitro. Soluble Aβ 1-42 aggregates were incubated for 3 h with different ratios of compound:Aβ (0.1:1, 1:1, 10:1). (A) Native gel electrophoresis and Western blot (6E10 anti-Aβ antibody) show reduction in soluble Aβ aggregates entering the running gel, with Aβ remaining in the stacking gel (arrowhead). (B) A11 oligomer-specific ELISA shows reduction in immunoreactivity following incubation with CNI-1493 and C1213. (C) CNI-1493 and C1213 reduce the Thioflavin T signal of insoluble Aβ 1-42 aggregates. (D) MTT assay of primary microglia treated for 48 h with soluble Aβ 1-42 aggregates incubated for 3 h with vehicle, CNI-1493 or C1213. Incubation of Aβ 1-42 aggregates with CNI-1493 or C1213 attenuates Aβ-induced reduction of the MTT signal. *** P < 0.001 Veh vs. Compound; ### P < 0.001 for dose-dependent reduction in signal.