Medalie D A, Tompkins R G, Morgan J R
Massachusetts General Hospital, Harvard Medical School, Department of Surgery, Boston, USA.
J Invest Dermatol. 1998 Nov;111(5):810-6. doi: 10.1046/j.1523-1747.1998.00368.x.
To aid in the investigation of factors that control the proliferation and function of melanocytes, we have characterized a skin equivalent model that supports melanocyte growth and function in vitro and in vivo. Passenger melanocytes survive and proliferate at low numbers when keratinocytes of the epidermis are cultured in serum-containing medium using a fibroblast feeder layer. When the surface of de-epidermalized acellular dermis was seeded with these cultured cells, the keratinocytes formed a stratified epithelium in vitro containing rete ridges, and the melanocytes were preferentially located in the bottom of these rete ridges. Melanocyte cell number was much less than in normal skin, but in some areas the melanocytes were in clusters, consistent with clonal growth of the cells. When transplanted to athymic mice, the grafts formed foci of pigmentation at 3 wk that expanded and repigmented the entire graft by 8 wk. Histologic examination of these foci revealed that they corresponded to clusters of melanocytes that proliferated and migrated to eventually repopulate the entire graft. In grafts of mixed cells from light and dark skin donors, distinct foci of pigmentation were obvious at 3 wk and, instead of progressing to complete repigmentation, these foci remained stable for over 6 wk. Histologic examination confirmed that these grafts of mixed cells were entirely repopulated with melanocytes and that the grafts contained distinct zones of melanocytes that were of exclusively dark or light skin origin. This model should be valuable for studying the clonal growth of melanocytes in the context of the epidermis.
为了有助于研究控制黑素细胞增殖和功能的因素，我们已对一种皮肤等效模型进行了表征，该模型在体外和体内均支持黑素细胞的生长和功能。当使用成纤维细胞饲养层在含血清培养基中培养表皮角质形成细胞时，过客黑素细胞能以低数量存活并增殖。当将这些培养细胞接种到脱表皮的无细胞真皮表面时，角质形成细胞在体外形成了含有 rete 嵴的复层上皮，黑素细胞优先位于这些 rete 嵴的底部。黑素细胞数量远少于正常皮肤，但在某些区域黑素细胞呈簇状，这与细胞的克隆生长一致。当移植到无胸腺小鼠时，移植物在 3 周时形成色素沉着灶，并在 8 周时扩展并使整个移植物重新色素沉着。对这些病灶的组织学检查显示，它们对应于增殖并迁移以最终重新填充整个移植物的黑素细胞簇。在来自浅色和深色皮肤供体的混合细胞移植物中，在 3 周时明显可见不同的色素沉着灶，并且这些病灶没有进展为完全色素沉着，而是在超过 6 周的时间内保持稳定。组织学检查证实，这些混合细胞移植物完全被黑素细胞重新填充，并且移植物包含仅来自深色或浅色皮肤的黑素细胞的不同区域。该模型对于研究表皮环境中黑素细胞的克隆生长应该是有价值的。
