Wilson C L, Sun T T, Lavker R M
Department of Dermatology, University of Pennsylvania, Philadelphia.
Skin Pharmacol. 1994;7(1-2):8-11. doi: 10.1159/000211266.
The slow-cycling cells in the bulge of the outer root sheath may represent stem cells for the hair follicle. With each new anagen (growing) phase bulge cells would give rise to a population of transient-amplifying cells which differentiate into outer root sheath and matrix keratinocytes. The lowermost part of the telogen (resting) follicle is composed of bulge cells lying in close proximity to the dermal papilla. In the mouse the first hair follicle growth is characterized by rapid follicular neogenesis, but the second and third growth cycles follow the normal follicular growth pattern. We have examined activity of cells in the bulge at the onset of anagen (growing phase) in the third hair cycle in Sencar mice, by treating animals at the end of the second telogen with colchicine to localize mitotic activity in the hair follicle. Mitoses were only seen in bulge cells during early anagen. This confirms that they proliferate transiently, solely at the onset of anagen and strongly supports the suggestion that bulge cells are the origin of the whole lower follicle in anagen.
外根鞘隆突部位的慢循环细胞可能代表毛囊干细胞。在每个新的生长期，隆突细胞会产生一群短暂扩增细胞，这些细胞分化为外根鞘和基质角质形成细胞。休止期毛囊的最下部由紧邻真皮乳头的隆突细胞组成。在小鼠中，第一次毛囊生长的特征是快速的毛囊新生，但第二次和第三次生长周期遵循正常的毛囊生长模式。我们通过在第二次休止期末用秋水仙碱处理Sencar小鼠，以定位毛囊中的有丝分裂活性，从而研究了第三次毛发生长期开始时隆突部位细胞的活性。仅在生长期早期的隆突细胞中观察到有丝分裂。这证实了它们仅在生长期开始时短暂增殖，并有力地支持了隆突细胞是生长期整个下部毛囊起源的观点。
