Figure 6.

Human fibroblast-derived neurons for human disease modeling. (a) Low magnification of Tuj1 (left) and peripherin (Prph, right) staining of healthy control (HC)-derived neurons. Scale bars: 500 µm. (b) High magnification of Tuj1 staining of HC-derived neurons. Scale bar: 100 µm. (c) NF200-positive cell derived from HC fibroblasts. (d) Current recording of an action potential train from a HC-derived neuron (17/33 induced neurons with peak Na current > 500 pA fired at least one action potential with peak greater than 0 mV). (e) Total (left) and TTX-resistant (middle) sodium currents from a single HC-derived neuron. Right panel shows persistent TTX-resistant sodium current recordings from a separate HC-derived neuron characteristic of Nav1.9. (f) RT-PCR for IKBKAP and GAPDH from single human induced neurons (left) and single human fibroblasts (right) show normal (black arrow) and abnormally spliced (red arrowhead) transcripts. Full-length gels are presented in Supplementary Fig. 10. (g) Low magnification of Tuj1 (left) and peripherin (right) staining of neurons derived from a patient with Familial Dysautonomia (FD). Scale bars: 500 µm. (h) High magnification of Tuj1 staining of FD-derived neurons. Scale bar: 100 µm. For all images, representative images were selected from human neurons generated in n=6 wells from three separate transductions. (i) Quantification of Tuj1-positive neurons in HC and FD-derived nociceptors (random intercept mixed-effects model p=0.26). (j) Neurite outgrowth per cell for HC and FD-derived Tuj1-positive nociceptors (random intercept mixed effects model p=0.012). (k) Number of branches per cell for HC and FD-derived Tuj1-positive nociceptors (random intercept mixed effects model p=0.017). For i–k, images were analyzed from three pairs of age-matched HC and FD patient lines from each of three separate transductions (n=20 wells/line). Error bars are ± SEM.