Fig. 3.

Intrinsic firing properties of hiPSC-derived neurons mature at a similar rate from plating to plating in control lines, and between control hiPSC lines 210 and 173. (A) Immunostaining with βIII-tubulin antibody and DAPI on neurons derived from control hiPSC 210 and 173 at D4–5 and D21–23 post plating. (B) Representative traces of action potentials evoked in control hiPSC 210- and 173-derived neurons in response to a 600 ms depolarizing current pulse at five recording windows between 4 and 38 days post plating. (C) The percentage of neurons capable of evoked firing, (D) repetitive firing (>2 APs) and (E) the peak firing frequency as a function of age. Data are reported as mean + SD. Number of individual platings at each time window from 2 lines is reported in the bottom of C–E with number of neurons in parentheses. All three properties were significantly different as a function of age (two-way ANOVA with post hoc Bonferroni test, results in Table 3). a, b, c and d denote significance from D10–11, D15–16, D21–23 and D35–38 post plating respectively within the same line. Numbers next to the letters represent degrees of significance with 1, 2, 3 and 4 denoting p value < 0.05, 0.01, 0.001 and 0.0001 respectively. There was no significant difference between cell lines (Table 3).