a, SY5Y cells were cultured without serum for different times in the absence and presence of cis or trans mAb, followed by IB for cis and trans p-tau. b, SY5Y and differentiated PC12 cells were treated with hypoxia in the absence and presence of cis or trans mAb for 48h, followed by staining for MTs. c, Differentiated PC12 cells were treated with hypoxia in the absence and presence of cis or trans mAb for 48 h, followed by live-cell microscopy to capture fast and slow transport of MI along neurites. d-g, SY5Y cells were cultured without serum for different times in the absence and presence of cis or trans mAb, followed by live/dead cell assay (d, e) and apoptosis assays using PARP cleavage (f) and Annexin V (g). h, i, SY5Y cells were co-transfected with GFP-tau or -tauT231A and p25/Cdk5, followed by live-cell imaging to observe cell death of GFP-tau expressing cells over 65 h (h), with quantification being shown (i) (mean ± S.D.). p values, ANOVA test.