Figure 9.

Effect of the increased secretion of Aβ42 from neurons derived from V642I–APP knock-in ES cells on primary cultured CNS-derived neurons. A, Cocultures of neurons derived from ES cells with primary cultured CNS neurons. The 7DIV of hippocampal neurons derived from E17 mouse embryos and cortical neurons derived from E14 mouse embryos were cocultured with either wtES-derived neurons (closed columns) or V642I–APP knock-in ES-derived neurons (open columns) on filter membranes of culture inserts for 3 d, followed by determination of their viability with WST-8 assay. Cell viability was estimated as percentage of control (cultured with culture insert in the absence of ES-derived neurons). Values were means ± SD of three independent experiments. B, Culture of CNS neurons in conditioned medium from ES-derived neurons. The 7DIV of hippocampal neurons derived from E17 mouse embryos and cortical neurons derived from E14 mouse embryos were cultured in medium conditioned from either wtES-derived neurons (closed columns) or V642I–APP knock-in ES-derived neurons (open columns) for 3 d, followed by determination of their viability with WST-8 assay. Cell viability was estimated as the percentage of control (cultured in fresh medium). Values were means ± SD of five and three independent experiments for hippocampal and cortical neurons, respectively. C, D, The effect of synthetic Aβ 1–42 on primary cultured CNS-derived neurons. The 7DIV of hippocampal (C) and cortical (D) neurons from E17 and E14 mouse embryos, respectively, were treated with (open columns) or without (closed columns) Aβ1–42 in the absence (-) or presence (+) of culture insert for 3 d, followed by determination of their viability with WST-8 assay. Cell viability was estimated as the percentage of control (without Aβ). Values were means±SD of three determinations. Asterisks indicate a significant difference between control and Aβ treatment, as determined by Student's t test (p < 0.01).