Matsuzaki T, Yoshizato K
Yoshizato MorphoMatrix Project; ERATO, JST, Higashi-hiroshima, Japan.
Wound Repair Regen. 1998 Nov-Dec;6(6):524-30. doi: 10.1046/j.1524-475x.1998.60605.x.
Hair dermal papilla cells are specialized mesenchymal cells that exist in the dermal papilla located at the bottom of hair follicles. These cells play pivotal roles in hair formation, growth, and cycling. Hair follicle formation is usually directed by an aggregation of dermal mesenchymal cells, the origin of dermal papilla cells, in the embryonic skin. We noticed that cultured dermal papilla cells also have hair-forming activity and do not lose the activity even after long-term cultivation, if they are cultured with conditioned medium from keratinocytes obtained from the sole or with a medium containing fibroblast growth factor. The secreted factors from keratinocytes and fibroblast growth factor are, therefore, important for maintaining the cellular properties of dermal papilla cells. Even if the hair bulb, including the hair matrix and the dermal papilla, has been removed from vibrissal follicles in vivo, the new hair matrix and papilla can regenerate from the rest of the follicle, and eventually a hair shaft regrows. It has been reported that hair bulb regeneration does not occur when the lower half of a hair follicle is removed. However, new hair bulbs were formed in the remaining upper halves of vibrissal follicles if the amputated follicles had been implanted under the kidney capsule. The formed bulbs were small and pelage-type, not large vibrissa-type. Histological studies showed that the new dermal papillae were derived from dermal sheath cells surrounding upper follicular epidermis, and the new hair matrices were produced from the follicular epidermis. Moreover, the upper halves of vibrissal follicles reformed large vibrissa-type bulbs when they were associated with dermal papillae or cultured papilla cells and implanted in the kidney. Thus, dermal papilla cells and probably dermal sheath cells have the ability to induce and form hair bulbs under preferred environmental conditions. Attempts to identify the genes and proteins associated with hair-forming activity of dermal papilla cells have been carried out. We and other groups successfully isolated the molecules that were specifically expressed in dermal papilla cells. The nature of the hair-producing factors could be understood through the studies of these molecules.
毛囊真皮乳头细胞是一种特殊的间充质细胞，存在于毛囊底部的真皮乳头中。这些细胞在毛发的形成、生长和周期性循环中起着关键作用。毛囊的形成通常由真皮间充质细胞（真皮乳头细胞的起源）在胚胎皮肤中的聚集所引导。我们注意到，培养的真皮乳头细胞也具有毛发形成活性，并且即使经过长期培养，如果与从足底获得的角质形成细胞的条件培养基或含有成纤维细胞生长因子的培养基一起培养，它们也不会失去这种活性。因此，角质形成细胞分泌的因子和成纤维细胞生长因子对于维持真皮乳头细胞的细胞特性很重要。即使在体内从触须毛囊中移除了包括毛基质和真皮乳头在内的毛球，新的毛基质和乳头也可以从毛囊的其余部分再生，最终毛发轴重新生长。据报道，当移除毛囊的下半部分时，毛球不会再生。然而，如果将截肢的毛囊植入肾包膜下，在触须毛囊剩余的上半部分会形成新的毛球。形成的毛球很小，是被毛型的，而不是大的触须型。组织学研究表明，新的真皮乳头来自上半毛囊表皮周围的真皮鞘细胞，新的毛基质由毛囊表皮产生。此外，当触须毛囊的上半部分与真皮乳头或培养的乳头细胞相关联并植入肾脏时，它们会重新形成大的触须型毛球。因此，真皮乳头细胞以及可能的真皮鞘细胞在适宜的环境条件下具有诱导和形成毛球的能力。人们已经尝试鉴定与真皮乳头细胞毛发形成活性相关的基因和蛋白质。我们和其他研究小组成功分离出了在真皮乳头细胞中特异性表达的分子。通过对这些分子的研究，可以了解毛发产生因子的性质。
