| Repair for the wound surface is a major issue in wound treatment. A difficult question is the repair for large area wounds and refractory wounds. Up to now, how to promote wound healing and reduce related complications to retrieve normal functions still remains an unsolved challenge. Stem-cell therapy and progress in tissue engineering provide new ideas and strategies. How to get satisfactory ―seed cells‖ is the key for the therapy. Epidermal stem cell is the major source for the genesis and regeneration of derma and its appendixes, they play important roles in wound healing. Research has suggested a broad application prospective for epidermal stem cells in clinic. However, the epidermal stem cells lay in stratum basal and only account for 1%~10% of the basal cells. Present isolation culture methods can only collect few cells and cost too much time. Besides, after many generations, cloning efficiency apparently drops, cells begin to differentiate and their proliferation acti vity also suffers reduction. How to amplify the epidermal stem cells in a short time period in vitro and at the same time maintain their multipotent property has become a major problem for the clinic application.For normal repair of the wounds, the regulation effect of the biological electric field in the wound cannot be neglected. Proliferation of the epidermal cells is positively associated with the biological electric field intensity in different parts of the wound. Previous results of our lab observed a significant outward current in dermal wound of rats. Enhancing the current can promote wound healing. In vitro experiments found that after simulation by bioelectricity on the epidermal stem cells, expression of K14, K19, α6-integrin and β1-integrin were up-regulated, which suggested that the simulation could maintain or even enhance multipotent potential of the cells. Down-regulation of K10 suggested that suitable simulation intensity would not cause differentiation. There was no significant reduction of the multipotent transcriptional factors’ mRNA levels, which suggested that biological electricity field can maintain their multipotent potential. All these results make us aware that biological electricfield may be the key to solve the problem mentioned above. Thus, in the article we experimented the effect of biological electric field on the epidermal stem cell cultures in vitro and how it affect wound healing.We first established endogenous simulation platform. Then we isolated P1 epidermal stem cells and inoculated they for further culture in our simulation platform to observe the effect of bioelectricity of different intensities(100mV/mm, 200mV/mm) on proliferation and migration. Finally we executed bioelectricity simulation on the epidermal stem cells and detected the wound healing effect applying wound transplantation.Our major results include:1. Differential attachment method by using collagen IV to isolate and select specific cells and culture them in K-sfm medium can successfully acquire epidermal stem cells in vitro.2. Bioelectricity stimulation within certain range can promote the proliferation of the epidermal stem cells.3. Bioelectricity can cause directed migration of the epidermal stem cells towards cathode, the migration rate increases with the enhance of electricity intensity.4. Application of the epidermal cells can effectively promote wound healing and up-regulate healing rate at all time points, shortening necessary time and improve the effect.5. Using the epidermal cells after bioelectricity stimulation for wound transplantation can also effectively promote wound healing and show better performance in healing rate, healing time and effect then simply using the stem cells. |
PDF Full Text Request