MAPT and Alzheimer disease: Moreover, neuronal internalization of fibrillized truncated tau and AD tau evaluated by different independent methods (flow cytometry, tau specific ELISA, immunocytochemical colocalisation of internalized AD tau with human tau antibody HT7 and Western Blot), resulted in a statistically significantly increased neuronal uptake of these pathogenic tau species over time (Fig. 5e, f, Additional file 1: Figure S1a, b).