Additive effects of p23 depletion and FAD-linked PS1 mutation on APP metabolism. A, Lysates of N2aSwe cells stably expressing wt PS1 or C410Y mutant were probed with antibodies specific for p23, APP, γ-secretase components, and calnexin. B and C, Quantitative analysis of secreted Aβ40 and Aβ42 in the media conditioned by wt and C410Y cell lines was performed using two-site ELISAs. The data represent mean ± SEM of three transfections. * p < 0.05; ** p < 0.01.