Experimental Study Of Bacterial Cellulose Membrane Loading Bone Marrow Mesenchymal Stem Cells To Promote Acute Wound Healing In Mice

A wound dressing is the most classic product used to protect the wound and promote wound healing.The traditional gauze dressing is simple to make and easy to use,but it has the disadvantages of easy adhesion to the wound,poor moisturizing effect and unsatisfactory healing effect.Therefore,in the field of wound repair and tissue regeneration,the research on the biological and functional treatment of materials is increasing day by day.Bacterial cellulose membrane(BCM)is considered to be a natural wound repair material that meets the requirements of modern wound dressings due to its excellent physical and chemical properties and biological characteristics.Its three-dimensional network structure can effectively prevent microbial invasion,avoid wound infection,ensure normal gas and liquid exchange during wound treatment,and make it a carrier for drug sustained release,thereby effectively promoting wound healing and promoting skin tissue regeneration.In tissue engineering,bone marrow mesenchymal stem cells(BMSCs)are usually used as seed cells for biological integration with biomaterials to ensure the stability of the cell microenvironment.In vitro studies have shown that BMSCs can adhere to BCM to proliferate stably and maintain the characteristics of stem cells,while BCM can induce BMSCs to produce type I collagen,thus providing mechanical stability for tissues and promoting tissue healing.Although the role of BMSCs in promoting wound healing has been extensively studied,and the clinical application effect of BCM is also obvious,there is no study to explore the combination of BCM and BMSCs for wound treatment.Therefore,this study was the first to explore the effect and possible mechanism of BCM and BMSCs biological integration in wound healing.ObjectiveBCM was loaded with BMSCs to prepare a bioactive wound dressing(BWD).By studying the effect and mechanism of BWD on acute full-thickness defect wounds in mice,the feasibility of BWD in the treatment of acute defect wounds was explored.MethodsMorphological and chemical identifications of BCM were investigated by porosity analyses,scanning electron microscopy,and Fourier-transform infrared spectroscopy.BMSCs were combined with BCM by multipoint injection to prepare BWD.The effects of conditioned medium(CM)of BWD on the proliferation and migration of human dermal fibroblasts(HDFs)and human vascular endothelial cells(HUVECs)were detected by in vitro experiments.The effect of BWD on wound healing of acute full-thickness defects in mice was detected in vivo.On the 7th and 14th day after injury,the collagen and angiogenesis of the wound were detected by HE staining and Masson staining.The expressions of Col-1 and Vegf-A and the activation of the Notch signaling pathway in vivo and in vitro were detected by quantitative reversetranscriptase polymerase chain reaction(qRT-PCR).The effect of BWD on Notch signaling pathway was verified by blocking Notch receptor cleavage with y-secretase inhibitor DAPT.Results1.Bacterial cellulose membrane has nano-pore structure,which provides structural conditions for gas transport and bacterial separation.Layer-by-layer filtration structure composed of multi-layer fibers can improve its barrier properties.Three-dimensional structure provides space for the adhesion and proliferation of BMSCs.2.BCM has good biocompatibility.BMSCs inoculated into BCM by multipoint injection can proliferate stably and grow radially around the puncture point.3.BWD-CM can effectively promote the proliferation and migration of HDFs and HUVECs in vitro,promote the expression of Col-1 gene in HDFs and up-regulate the expression of Vegf-A gene in HUVECs.4.BWD can effectively promote the healing of acute full-thickness wound in mice and promote collagen and angiogenesis.5.BWD promotes wound healing by activating Notch signaling pathway,which can be partially blocked by DAPT.ConclusionThis study aimed to creatively explore the effect of the BCM combined with BMSCs on wound healing.The results demonstrated that BWD could promote the wound healing capacities of HDFs and HUVECs in vitro and accelerate wound healing in vivo.This effect may be related to the activation of the Notch signaling pathway.Our findings provided theoretical support for the clinical application of the BCM,and innovative research and production of BWD will provide a new aspect for the treatment of skin wounds.