Novel method for isolating human melanoblasts from keratinocyte culture

The characterization of melanoblasts is important for understanding their in vivo development, melanoma formation, and pigment‐related disorders. However, no methods have been reported for the isolation of melanoblasts from human skin. Using a ‘calcium‐pulse’ technique, involving the differentiation of human keratinocytes with high calcium and the subsequent spontaneous separation of the epidermal sheets, we effectively isolated human melanoblasts (keratinocyte‐adapted melanoblasts, KaMBs) from keratinocyte culture. The KaMBs expressed early melanogenesis‐related genes, including BRN2, which is a known melanoblast marker. Moreover, the KaMBs displayed much higher proliferative and growth capacities than the primary melanocytes. Considering that keratinocytes might provide an in vivo‐like environment for KaMBs during isolation and in vitro culture, the ‘calcium‐pulse’ technique offers an unprecedented, easy, and efficient method for the isolation of human melanoblasts, retaining the original characteristics of these cells.