Effects of stem cell factor and extracellular matrix on melanocyte differentiation in mouse neural crest cell culture.

应用免疫组织化学技术和多巴反应研究了可溶性干细胞因子（s-SCF）在体外培养的小鼠神经嵴细胞（NCC）黑素细胞发育中的作用。c-KIT（+）树突状细胞在s-SCF（50 ng/ml）作用下培养第3天出现，第9天后达平台期，而在无s-SCF作用下培养第9天，c-KIT（+）树突状细胞消失，第5天及以后加入s-SCF后，c-KIT（+）树突状细胞消失。结果表明，SCF在c-KiIT（+）细胞的形成过程中可能起一定作用，并存在一个临界时间（第0-5天）当必须加入s-SCF以诱导c-KIT（+）细胞时，在含有s-SCF的外植体培养物中没有发现DOPA阳性黑素细胞，而加入霍乱毒素（CT）后，s-SCF对DOPA阳性黑素细胞的出现和向成熟黑素细胞分化的作用均显著增强。这表明，额外的因素，如CT，可能是必要的，以诱导分化为成熟的黑素细胞。

We investigated the role of soluble stem cell factor (s-SCF) in the melanocyte development of cultured mouse neural crest cells (NCC) by using immunohistochemical techniques and DOPA reaction. c-KIT (+) dendritic cells were found on Day 3 of the explant culture with continuous presence of s-SCF (50ng/ml) and reached a plateau after Day 9, while there were no positive cells left at Day 9 without s-SCF.When s-SCF was added on Day 5 or after, c-KIT (+) cells did not appear. Tyrosinase, TRP1, and TRP2 positive cells all appeared by Day 9 in cultured NCC with s-SCF.These results suggest that SCF may play a role in the development of c-KiIT (+) cells and that there is a critical time (Days 0-5) when s-SCF must be added to induce c-KIT (+) cells DOPA positive melanocytes but no mature melanocytes were found in the explant culture with s-SCF,while the effects of s-SCF on both DOPA positive melanocyte appearance and the differentiation into mature melanocytes were markedly enhanced by the addition of cholera toxin (CT) to the culture. It is indicated that additional factors, such as CT,may be necessary to induce the differentiation into mature melanocytes.