2022 年 27 巻 1 号 p. 1-13
Hair follicle development and cycle are regulated by the reciprocal interactions between epithelial and mesenchymal cells. Mechanisms responsible for the regulation have mainly been studied using experimental animals such as rodent fetuses. The purpose of this study is to understand such communications by using in vitro cell culture models of human hair follicle-derived cells. Human dermal papilla cells (DPCs) were cultured using 2-dimensional (2D), spheroid (3D), and spheroid microwell array cultures in an oxygen-permeable substrate (3D-oxy). Exosomes secreted in the culture media were collected and purified. All three types of exosomes moderately promoted proliferation of human hair follicle stem cells (HFSCs). Exosomes from the 3D-oxy culture most efficiently upregulated the expression of CD200, CD34, and K15 in HFSCs compared to those from the other two culture methods. To investigate the effects of exosomes on in vitro hair follicle formation, mouse embryonic epithelial and mesenchymal cells were used to prepare hair follicle organoids. The expression analysis of trichogenic and HFSC marker genes revealed that exosomes from the 3D-oxy culture were the most effective in maintaining stem cells and stimulating hair follicle sprouting in vitro. Exosomes from human DPCs may have substantial potential for treating patients with hair loss.
