Fig. 9

Microglia uptake phosphorylated tau in vitro, facilitated by scFvMC1. (a) Primary mouse microglia (P2 C57Bl/6 J pups) were treated in vitro for 2 h with PHF-tau +/− scFvMC1 (scFv/PHF ratio of 10/1). Total tau ELISA. Column A: PHF levels are expressed as % of starting PHF concentration measured after incubation on cell-free plates (− primary microglia); column B: amount of PHF in medium upon combination with scFvMC1, on cell-free plates (− primary microglia); column C and column D: PHF levels on microglia seeded plates (+ primary microglia), with or without scFvMC1. A vs C (*p < 0.05, unpaired t test with Welch’s correction); C vs D (*p = 0.0137, unpaired t test with Welch’s correction); B vs D (**p = 0.0019 unpaired t test with Welch’s correction). Data are collected from three different experiments, with treatments run in quadruplicates. Graphs are means +/− SEM. (b, upper panel) Representative immuno-blotting (PHF1 antibody: anti-pSer396/404) of PHF-tau in the corresponding microglia lysates; (b, lower panel) scFvMC1 expression verified using anti Myc-tag antibody. NT is non treated microglia; PHF is microglia treated with PHF-tau; PHF + scFv is microglia co-treated with PHF-tau and scFvMC1; scFv is microglia treated with scFvMC1