Reconstitution of Hair Follicles

近年来，几种体外方法被用于毛发生物学的研究。主要的方法可分为两类：单个卵泡细胞培养和维持完整的卵泡。此外，还介绍了第三种方法，即在适当的条件下，从某些组织和器官中分离出来的细胞通过旋转培养可以重新形成原始的组织或器官。我们以前曾报道过用旋转培养和漂浮培养两步培养法从大鼠胎儿上唇的单个细胞悬液中重建毛囊。旋转提供了细胞的分选，漂浮促进了组织分化。在本研究中，我们在先前方法的基础上增加了移植程序，以观察通过这种方法获得的细胞聚集体是否可移植，以及移植是否促进了组织分化。对浮选前后的骨料进行接枝处理。移植后10天，毛囊的分化与体内的毛囊相似。两种移植物的分化程度无明显差异。因此，即使在漂浮步骤后获得的聚集体被嫁接，移植过程也能显着增强组织分化。我们研究的最终目标是增加临床人类病例中的毛囊数量。为此，我们必须解决以下两个问题。一个问题是如何增加具有改造卵泡能力的细胞的数量。第二个问题是如何将增加的小叶返还给患者。在本研究中，我们重点研究了第二个问题。

In recent years, several in vitro methods have been used for research of hair biology. The predominant methods could be classified into groups : culturing of individual follicular cells and maintaining of intact follicles. Moreover, a third method was described, in which dissociated cells derived from some tissues and organs could form the original tissues or organs again by rotation culture under proper conditions. We have previously reported reconstruction of hair follicles from a single cell suspension of rat fetal upper lip by a two-step culture method consisting of rotation and floatation cultures. Rotation provided sorting out of the cells and floatation facilitated histodifferentiation. In the present study, we added grafting procedures to the previous method to see whether cell aggregates obtained by this method were graftable, and whether the grafting promoted histodifferentiation. The aggregates before and after floatation step were subjected to grafting. Differentiation of hair follicles comparable to those in vivo was confirmed ten days after grafting. No difference in the degree of differentiation was observed between the two kinds of grafts. Thus the grafting procedure resulted in a significant enhancement of histodifferentiation even when aggregates obtained after the floatation step were grafted.An ultimate goal of our research is increasing the number of hair follicles in clinical human cases. For that aim, we must solve the following two problems. One problem is how the number of the cells which have a capacity of reforming the follicles can be increased. The second is how the increased folicles can be returned to patients. In this study, we focused on the second problem.