| Epithelial-mesenchymal interactions play an important role in the development and regeneration of many tissues, such as tooth, bowel, feather, and so on. It has been showed that a group of specialized mesenchymal cells located at the bottom of the hair follicle, known as the dermal papilla cells, play pivotal roles in the folliculomorphogenesis and mature hair follicle cycling. And the dermal papilla cells, the major mesenchymal component of hair, are important in the study of follicle. The dermal papilla cells originate from condensed mesenchymal cells that lie beneath the epithelial hair germ cells (placode) in embryonic skin. Dermal papilla cells have now been cultured from a great variety of follicles, including rat whisker, rat pellage, sheep, and human skin. Cultured dermal papilla cells resemble fibroblast in appearance, but generally exhibit an aggregative behavior in culture, forming small clumps of cells overlapping each other with other areas of the dish remaining clear, unlike the parallel array of confluent dermal fibroblast. The character of aggregation would be losing along with the dermal papilla cells' cultivation, those after sixth passage would fail to coagulate.The tendency of aggregation is one of the significant characters of the dermal papilla cells, and the aggregative behavior of the dermal papilla cells is associated with their biologic function and differentiating state. However little is known about the molecular mechanisms of the aggregative behavior of dermal papilla cells, and about the importance of the growth associated proteins of the aggregating dermal papilla cells in the folliculomorphogenesis and mature hair follicle cycling.The papilla is an inductive structure that sends and receives signals to affect the development of hair follicle and hair cycling. Recent studies have identified many signaling molecules in hair follicle morphogenesis and hair cycling, such as fibroblast growth factors Supported by the National Science Foundation of China (No 30200249) and Chongqing Scientific Foundation Committee for the major projects (No 2001-8-4)(FGFs), bone morphogenetic proteins (BMPs), sonic hedgehog (Shh), neurotrophins, platelet derived growth factor (PDGF), and so on. Most of these factors are derived from the epithelial cells, and act as a cytokine network controlling follicle developing and hair cycling, at present we couldn't identify any key molecules in this cytokine network. So the specific mechanisms of the follicular development of and the hair cycling couldn't be clearly interpreted from the studies of these factors, but little is known about growth associated protein in the dermal papilla cells that have a direct role in the dermal condensation process and hair follicle cycling. It is said that the biologic significance of the growth associated proteins excreted by the aggregated dermal papilla cells would be an important content in the present hair follicle study. Based on the above cognition, we think that the study of the growth associated protein excreted by the aggregated dermal papilla cells would help to explain the molecular mechanisms of the aggregative behavior of the dermal papilla cells and the roles of growth associated protein in the follicle developing and hair cycling. So, collected conditioned medium of lower passage human dermal papilla cells and prepared for conditioned medium, use it to culture the non-aggregated dermal papilla cells and treat patient with alopecia areata subcutaneously, in order to explain the effects on the non-aggregated dermal papilla cells in dermal papilla cell conditioned medium to show the regulating role to hair cycling, and to probe a new way in treatment baldness disease.In this study, the human adult dermal papilla cells were firstly isolated and cultured from scalp hair follicle, and these cultured dermal papilla cells exhibited an aggregative behavior. The aggregative ability would be losing along with the dermal papilla cells' cultivation, and the aggregative characteristics of dermal papilla ce... |
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