Induction of melanocyte precursors from neural crest cells surrounding the neural tube-like structures developed in vitro using mouse ES cell culture

Neural crest cells differentiate into various cell types including melanocytes. In this study, we wanted to induce neural crest cells locating outside of neural tube by culturing mouse ES cells with retinoic acid (RA) and bone morphologic protein 4 (BMP4) in vitro, which mimicked the appearance of neural crest cells in the fetus. Histological examination of the cell aggregates composed of ES cells treated with RA and BMP4 disclosed emergence of neural tube-like structures surrounded by slug expressing neural crest cells. We detected melanocyte associated mRNAs such as pax3, sox10, Mitf and tyrosinase by RT-PCR of the aggregates. The neural crest cells expressed KIT and tyrosinase, indicating their differentiation to the melanocyte lineage. To accelerate the melanocyte induction, the cells were further treated by stem cell factor and endothelin 3 and then were transplanted to mouse femoral quadriceps muscles. They adhered to the recipient muscle tissue and retained the characteristics of melanocyte precursors, including expression of slug, KIT, endothelin receptor B and tyrosinase. Collectively, the neural crest cells derived from ES cells have a potency to differentiate into melanocyte precursors and they may be applicable for use in certain disease conditions such as vitiligo vulgaris in future.