The Effects Of Low Frequency Electromagnetic Fields On The Proliferation Of Epidermal Stem Cells Cultured In Two Different Scaffolds

Objectives:To discuss the effects of low frequency electromagnetic fields (LFEMF) on the proliferation of human epidermal stem cells(hESCs),which seeded in two different scaffolds of collagen sponge and chitosan in vitro,to provide a good three-dimensional model circumstance for researches about the effects of LFEMF on ESCs,and to provide a good scaffold material for skin tissue engineering.Methods:hESCs that separated and purified in vitro,were grafted into collagen sponge scaffolds and chitosan scaffolds with a method of air-liquid culture,and then were stimulated by LFEMF(magneticfield intensity 5mT,30min/d).According to different stimulation frequencies,this study set up three treatments(1Hz group,10Hz group and 50Hz group)and blank control group without LFEMF stimulation,we investigated the effects of LFEMF stimulation on growth and proliferation of hESCs by stain of HE and DAPI,and under inverted microscope and scanning electron microscope.The data of DAPI staining(2d,7d,10d and 14d)which assembled by micrograph soft,was used to analyze the cells proliferation at every time point by statistical method.Results:hESCs cultured in two different scaffolds had a good growth,the cells began to attach scaffolds for 2 days,and cells in 50Hz group can grow as flakiness after day 14.The difference of LFEMF for promoting hESC proliferation among different frequencies groups had statistical significance(F=160.73,P=0.000),and the difference of cells proliferation between tow different scaffolds also had statistical significance(F=71.13,P=0.000).Cultured for day 7,the effects of LFEMF for promoting cells proliferation began to appear to compare with other groups(P＜0.05), the difference between blank groups of two different scaffolds had statistical significance(P＜0.05);After day 7 or 14,compared the date of every LFEMF-treated groups of collagen sponge scaffolds and 10Hz or 50Hz group of chitosan scaffolds to the one of blank control group,the results had statistical significance(P＜0.05),and contrasted to the number of chitosan scaffolds,the one of every groups of collagen sponge scaffolds was lager(P＜0.05).Conclusion:Both collagen sponge and chitosan can be used as a good threedimensional scaffolds for ESCs cultured in vitro,collagen sponge is excellent as a scaffold material for skin tissue engineering.LFEMF under different frequencies can promote hESCs proliferation,different frequencies produce different promotion effects,and ESCs/scaffolds compounds can be applied to the further researches on skin tissue engineering.The LFEMF has comparatively large potentiality on skin tissue engineering.