Fig. 1. The stem cells express neural crest and sensory lineage-specific markers. (A-D,F) Undifferentiated dissociated cells were plated 5 hours on PDL and immunocytochemically stained as indicated below. Cells were counterstained with nuclear Hoechst staining. All cells with an intact nucleus expressed the stem cell/progenitor marker nestin (red) and the low-affinity neurotrophin receptor p75^NTR (green), as well as the GDNF family receptor Ret (red in F). (E) Expression of indicated transcription factors and receptors in the E11.5 dorsal root ganglion (DRG) and stem cells (SCs) determined by RT-PCR. Stem cells expressed mRNAs for the neuronal marker Ret as well as the sensory lineage markers Brn3a, Ngn1 and Ngn2. Notably the stem cells expressed the transcription factor Krox20, a transcription factor exclusively expressed by boundary cap cells lining the DREZ. The stem cells did not express mRNAs encoding CNS and kidney specific transcription factors Otx1, Pax2 and Pax5. Abbreviations: DRG, dorsal root ganglia; SCs, stem cells. RT-, reverse transcriptase negative. Scale bars: 25 µm.