Abstract:

Objective To study the in vitro culture condition for melanoblasts from human foreskin tissue. Methods The skin tissue taken from foreskin of children was treated with 0.5% dispase II to separate epidermis from dermis, then with trypsin to obtain single cell suspension, which was cultured in modified medium for melanoblasts, i.e., MCDB254 medium supplied with several cell growth factors. Finally, melanoblasts were obtained based on the difference of adhesion speed. The morphology and proliferation of cultured melanoblasts were observed under a light microscope. DOPA staining, immunostaining with anti- S-100 and -tyrosinase related protein 2 （TRP2） antibodies, and transmission electron microscopy were performed to identify the cultured melanoblasts. Results The cultured human melanocytes displayed a match-like shape, scattered arrangement, symmetric double poles, slim cell body, highly refractive nuclei; meanwhile, the melanoblasts exhibited plentiful cytoplasm, large volume, bipolar or irregular shape and clonal growth. Additionally, the melanocytes were positive for TRP2, S-100 and Dopa staining, while the melanoblasts were positive only for TRP2. Electron microscopy revealed the presence of mature melanin granules （stageⅢ - Ⅳ） in melanocytes but immature melanin granules （stageⅠ） in melanoblasts. Conclusion Stable pure culture of melanoblasts has been realized with the reformed medium, which may lay a foundation for the investigation into the mechanism of epidermal pigmentation.

Key words: [Key words] Melanoblasts;In vitro;immunohistochemistry