Fig. 6

Abrogated network activity and elevated calcium influx precede neurotoxicity caused by serum containing α-syn AAb. (A) Scatter plot of electrical activity of individual neurons (in neuron-astrocyte co-culture at div 14), showing loss of synchronized activity after 3 h of serum treatment. Each dot represents a calcium transient as a surrogate for action potentials, while vertical lines represent non-stimulated, coordinated network activity, as recorded by the GCaMP6f sensor. (B) Quantification showing a significant decrease in non-synchronous transients at 3 h after serum treatment as compared to the untreated condition. (C) Representative live cell images of neuron-specific NmC and GCaMP6f expression in α-syn + NmC overexpressing cells, in untreated control and after 3 h of treatment with serum containing α-syn AAbs. (D) Quantification of percent calcium-filled cells (relative to NmC-labelled neurons) at 3 h post-serum treatment as compared to the untreated condition. (E) Scatter plot with correlation coefficient (r) and associated significance (p) showing a significant negative dependence between percent calcium-filled cells after 3 h and percent NmC positive cells after 1 d of treatment with serum containing α-syn AAbs. N = 4–5 biological and 8–9 technical replicates. Statistics by unpaired Student’s T-test; statistical power (1-ß error probability) > 0.9 for all conditions. *** = p < 0.001