Transformation Of Mouse Dermal Fibroblasts Into Dermal Papilla-like Cells Under Spherical Culture

Hair follicle is a part of the skin,composed of mesenchymal and epithelial tissue.There is a group of special mesenchymal cells in the hair follicle,called dermal papilla(DP)cells.The transplanted DP cells can interact with epidermal cells to induce the reconstruction of hair follicles in mice.However,DP cells quickly lose their ability to induce hair regeneration over passages in vitro.In this paper,a series of experiments were designed to explore whether mouse dermal fibroblasts could be converted into dermal papilla-like cells under spherical culture in hope of securing a new source of DP cells.The main research contents are as follows:1)Dermal papilla was isolated from the whiskers of mice by modified microanatomy and enzyme digestion method.The extracted cells were identified as dermal papilla cells at the gene level and protein level by q RT-PCR,alkaline phosphatase staining and cellular immunofluorescence staining.2)Low adhesion surface was prepared by coating the 96-well plate with soft agarose film,on which the sizes of formed cell aggregates were controlled by the number of seeding cells in the wells.The effects of aggregate size of mouse dermal fibroblasts on the poetntial of being converted into dermal papilla-like cells were investigated.3)A GFP reporter gene vector driven by ALP promoter was constructed,and then evaluated in terms of reflecting the dynamic expression of ALP in mouse dermal fibroblasts in2 D and spherical cultures.The studies demonstrated that the extracted dermal cells were indeed mouse dermal papilla cells,and the expression of DP-specific markers decreased after in vitro subculturing.The low adhesion surface of agarose membrane induced mouse dermal fibroblasts into cell aggregates and up-regulation of DP-specific marker genes in mouse dermal fibroblasts,but the sizes of cell aggregates didn't display remarkable effect on cellular features.The constructed GFP reporter gene vector driven by ALP promoter were reflecting the changes of cultured cells in ALP expression,which would provide a straightforward,simple and reliable tool for monitoring the transition of mouse dermal fibroblasts into DP-like cells under spherical culture.