Fig. 5

Associations of Aβ and tau peptides with MEA and neurite integrity. A-F Effect size on neurite integrity and spontaneous activity was examined as a function of age at death (A&D), postmortem interval (B&E), and sex (C&F). Data points in C&F are colored by category: LP-NCI (blue), HP-NCI (green), and AD (red). P-values were calculated by Spearman correlations (A-B&D-E) or Mann-Whitney test (C&F). G-J Aβ levels were measured by ELISA in TBS-soluble brain extracts and compared across categories. Aβ42 (G) and Aβ42:40 (H) were measured by 6E10 MSD ELISA, and Aβ oligomers were measured using two different ELISAs: both used 3D6 for detection and for capture antibody one used 71A1 and the other used 1C22. ANOVA with Dunnett T3 multiple comparisons test, p-values as listed. K-O Tau peptides were measured using mass spectrometry and ELISA and compared across categories. Scatter plots show the relative abundance of all tau peptides (K), tau peptides of the N1 and N2 domains “N1,N2” (L), tau peptides of the second MTBR, “MTBR2” (M), and tau phosphorylated at T181 (pT181) and T217 (pT217) (N-O). One-way ANOVA with Dunnett T3 multiple comparisons test, p-values as listed. P Heatmap of Spearman correlation coefficients calculated between the measures in (G-M) and effect size in the MEA and neurite integrity assays. *, p < 0.05. Q Graph of the strongest association between tau peptides with the N-terminal inserts and neurite integrity. p = 0.0004