Fig. 3.

C10.2 and D1.2 reduce tau seeding in rTg4510 cortical neuronal cultures without blocking the uptake of seeds into neurons. (A) Uptake of human tau from rTg4510 P3 material was measured in tTA control neurons not expressing human tau. The uptake was measured as spots inside the cells detected by the human tau-specific E1 antibody. Preincubation of P3 material with C10.2, D1.2, or C10.1 does not prevent tau seed uptake. (B) In the same experiment, the uptake of antibodies was detected by anti-mouse IgG and measured as positive spots inside the neuronal cell bodies. Data in A and B are presented as the mean ± SD and represents quantifications from three wells with 20 fields/well analyzed. (C) Tau seeding was analyzed with the Cisbio tau aggregation assay in rTg4510 neuron cultures. Before addition of rTg4510 P3 seeding material to the neurons, it was preincubated with C10.2, D1.2, C10.1, or control mouse IgG. An equal volume of P3 isolated from tTA controls was added to the neuronal cultures as negative control not inducing tau seeding. Neurons seeded at DIV7, medium changed at DIV11, and cells lysed at DIV15. Data are presented as percentage aggregation normalized to total protein in relation to IgG control, mean ± SD from 5 to 15 wells from 2 to 4 independent experiments. One way ANOVA Newman-Keuls multiple comparison test, ^∗P < .05; ^∗∗∗P < .001; n = 10–60. Abbreviations: ANOVA, analysis of variance; DIV, days in vitro; IgG, immunoglobulin G; SD, standard deviation.