Electrophysiological Assessment of Neurons Differentiated from HD and Isogenic Control hiPSCs
(A) Raster plots of spike time stamps indicating spontaneous activity in differentiated neurons as measured by multi-electrode arrays. Raster plots representative of n = 3 biological replicates for CAG180 and HD-C#1 and #2, n = 2 biological replicates for CAG33. See also Figure S4.
(B) Representative image of dye-filled neuron from isogenic control hiPSCs.
(C) Action potential recordings from the isogenic control hiPSC-derived neurons shown in (B). While small current pulses evoked a single action potential (left), a larger current pulse evoked a train of action potentials (right) In both cases, the first action potential was delayed relative to the onset of the depolarizing current pulse. Resting membrane potential was −85 mV.
(D) Representative example of spontaneous action potentials (sAPs) recorded from an isogenic control hiPSC-derived neurons.
(E) Probability of observing sAPs measured in CAG33, CAG180, and HD-C#3 neurons.
(F) Frequencies of sAPs for CAG33, CAG180, and HD-C#3 neurons.
(G–I) Passive membrane properties of hiPSC-derived neurons. Similar values were observed for membrane capacitance (G), input resistance (H), and resting membrane potential (I) across all three experimental groups. Sample sizes: CAG33 = 24, CAG180 = 31, and HD-C#3 = 28.