Figure 3.
(A) Representative TIRFM images with arrows depicting the increased fraction of Aβ oligomers on the surfaces of hippocampal cells. The oligomeric fraction of Aβ42 and Aβ40 (B) on cell membranes and in solution prior to incubation with cells (aggregation concentrations used were 1 μM Aβ42 and 2 μM Aβ40); Aβ species were analyzed at different times during the aggregation reaction. For characterization of species prior to incubation with cells, the data were derived from three separate incubations. The oligomeric fraction of Aβ interacting with cell membranes as a function of different incubation concentrations of Aβ42 (C) and Aβ40 (D) (ANOVA single factor p = 0.17 for Aβ40 and p = 0.65 for Aβ42); distribution of sizes of oligomers after 4 h of aggregation of Aβ42 (E) or Aβ40 (F) present in solution (prior to incubation with cells) and on cell membranes (aggregation concentrations used were 1 μM Aβ42 and 2 μM Aβ40, n = 30–50 cells). All error bars are SEM; * is p < 0.05; ** is p < 0.01; n.s. p > 0.05.