Fig. 5

The competition between labeled and unlabeled extracellular Tau Monomers and fibrils for intraneuronal accumulation. The uptake and accumulation of 50 nM fluorescently labeled monomers (FL-Mono, A) and small fibrils (FL-S-fib, B) in the presence of increasing concentrations of unlabeled Tau Monomers (Mono, blue bars) and small fibrils (S-fib, orange bars) after 20 h of incubation in iPSCNs (A, B), and in LUHMES neurons (C, D). Significance was calculated by comparing Mono and S-fib at each concentration versus “0” and versus each other. E The neuronal accumulation of fluorescently labeled oligomers (50 nM) in iPSCNs neurons after 20 h of incubation in the presence of a 5-fold higher concentration of unlabeled monomers and oligomers (250 nM). F The uptake and accumulation of 25 nM FL-Mono in the presence of a 4-fold higher concentration of unlabeled Tau Mono and cofactor-free fibrils (Cof-free-fib) after 20 h of incubation. G The uptake and accumulation of 25 nM fluorescently labeled Cof-free-fib (FL-Cof-free-fib) in the presence of a 4-fold higher concentration of unlabeled Tau Mono and Cof-free-fib after 20 h of incubation. Significance compared to the untreated control (UTC). Error bars represent SEM; n ≥ 3 independent experiments per experimental condition. Two-way ANOVA followed by Tukey post-hoc test; ns: not significant, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001