Fig. 4

Characterization of amyloid precursor protein (APP) and amyloid precursor protein carboxy-terminal fragment (APP-CTF) expression during neuronal differentiation. Representative immunoblots of (a) APP and APP-CTF in control neurons (ctrl-1), early-onset familial Alzheimer’s disease (fAD)-derived neurons (fAD-1–fAD-4), and (b) sporadic Alzheimer’s disease (sAD)-derived neurons (sAD-1–sAD-6) at terminal differentiation day 14 (TD14), TD28, TD42, TD56, and TD70. Quantification of (c) APP and (d) APP-CTF signals at TD70 was normalized to GAPDH. Data are presented as mean ± SEM (n = 3). Dunnett’s test was performed to evaluate the significance of groups compared with control (*p < 0.05)