Nanba D, Hieda Y, Nakanishi Y
Department of Biology, Graduate School of Science, Osaka University, Toyonaka, Osaka, Japan.
J Invest Dermatol. 2000 Jan;114(1):171-7. doi: 10.1046/j.1523-1747.2000.00842.x.
Early hair follicle morphogenesis proceeds with the formation of a hair placode, the downgrowth of the hair plug into the mesenchyme, and the development of an elongated hair follicle - processes that involve a series of exchange of messages between epithelium and mesenchyme. Regulation of epithelial cell adhesion during hair morphogenesis has been demonstrated in terms of the changing expression patterns of E- and P-cadherins. In this study, distribution patterns of several major components of desmosomes and hemidesmosomes, which are the most prominent cell adhesion systems in epidermal tissues, were examined during early morphogenesis of mouse pelage hair follicles. We found that both desmosomal and hemidesmosomal adhesion systems became downregulated in hair placodes and were much reduced or almost lost in hair plugs, which persisted in the region containing hair matrix. Downregulation of the adhesion systems in hair plugs was confirmed by electron microscopy. Similar distribution patterns of these molecules were obtained in the developing follicles in cultured skin. It may be that epidermal cells at the initial stages of hair development respond to the first mesenchymal message by grossly changing their cell adhesion systems and that the resultant changes in cell adhesivity underlie early hair follicle morphogenesis.
早期毛囊形态发生过程包括毛基板的形成、毛栓向间充质的向下生长以及细长毛囊的发育，这些过程涉及上皮和间充质之间一系列的信息交换。在毛发形态发生过程中，通过E -钙黏蛋白和P -钙黏蛋白表达模式的变化，已证实上皮细胞黏附的调控。在本研究中，我们检测了桥粒和半桥粒的几个主要成分的分布模式，它们是表皮组织中最主要的细胞黏附系统，检测时间为小鼠体毛毛囊的早期形态发生过程。我们发现，桥粒和半桥粒黏附系统在毛基板中均下调，在毛栓中大幅减少或几乎消失，而在含有毛基质的区域持续存在。通过电子显微镜证实了毛栓中黏附系统的下调。在培养皮肤中的发育毛囊中也获得了这些分子的类似分布模式。可能毛发发育初始阶段的表皮细胞通过显著改变其细胞黏附系统来响应最初的间充质信号，并且由此产生的细胞黏附性变化是早期毛囊形态发生的基础。
