Study On Secretomes Derived From Human Umbilical Cord Mesenchymal Stem Cells Promoting Gingival Tissue Repair And Regeneration

Objective:The purpose of this study is to investigate the effects of human umbilical cord mesenchymal stem cells secretomes（h UCS）on gingival tissue repair and regeneration from the cellualr level and animal level,and to provide theoretical support for clinical treatment of gingival atrophy.Method:SD rat gingival fibroblasts were performed to isolation,culture,passage and expansion as well as cryopreservation and resuscitation.And then,GFs were identified by immunocytochemical analysis.CCK-8 method and cell scratch method were practiced to examine the effect of h UCS with various concentrations on the biological behavior of SD rat gingival fibroblasts,and to figure out the most suitable drug concentration.Establish gingival recession rat model and inject h UCS around the recession area.Analyze histological staining.q RT-PCR was performed to investigate the expression of fibro-related factor Col-1、Col-3 and vein formation factor VEGF.Result:Primary cells of SD rat gingival fibroblasts were fusiform or asteroid.The cryopreservation and resuscitation of GFs were successful.The biological character of the third passage of GFs was similar to that of the original generation.The immunochemistry study indicated that vimentin showed positive staining while cytokeratin showed negative staining,which meaned to originate from mesoblastma.Cell assays showed that h UCS could promote the proliferation,healing and migration of GFs（P<0.05）.The optimal concentration was 10μg/m L.In animal experiments,HE staining and q RT-PCR experiment indicated the recovery effect of h UCS group was better than the Control group.HE staining results showed that the gingival epithelial spikes were significantly shortened and flattened,and the combined epithelium migrated to root tip obviously in Control group.In the drug administration group,the gingival epithelial spikes were clear and the combined epithelium was attached to the cementum enamel.The expression of Col-1、Col-3、VEGF in h UCS group was significantly higher than in control group.Conclusion:h UCS has been shown to promote gingival tissue repair and regenerate at both cellular and animal level.h UCS can improve the expression of fibrine-related factors Col-1 and Col-3 as well as angiogenic factor VEGF.Therefore,h UCS can offer an excellent ability to promote gingival soft tissue repair and regenerate,as well as an outstanding potential of clinical treatments.