Figure 1.

(A) Schematic illustration of the differentiation protocol to generate hESC–derived nociceptor–like cells: arrows indicate time points of virus infection, selection (addition of puromycin) and splitting of cells. Graphs show characteristic morphology of cells at the indicated time points: –1 day (d) neural crest–like cells (NCLCs), 2 d NGN1 expression, indicated by GFP–signal; 4d neural progenitors show small neurites; ≥21d neurons with long processes can be observed. (B) Live cell imaging of neuronal progenitors derived from the hESC TRKA–tomato reporter cell line: left picture shows a bright field (bf) image, right picture the tomato signal of cells 6 days after doxycycline–induced expression of NGN1. (C) Immunostaining of hESC–derived NCLCs 2 days after induction of NGN1–expression. As early as 2 days after NGN1 induction, the presence of the pan–sensory marker ISLET1 (ISL1) is detectable in a subset of cells. (DAPI: blue; ISL1: green). Scale bars: 20 μm.