Experimental Study Of ASCs Combined With POC-PLA Patch For The Reconstruction Of Full-thickness Chest Wall Defects

Complete form of chest wall protection of pleural structure;also play an important role in the respiratory movement.Various causes of full-thickness defect of chest wall reconstruction are always a difficult problem in cardiothoracic surgery,and plastic surgery.For the repair of large chest wall defect,repair materials can now choose constantly,the doctor can according to their own experience needs to be combined with clinical patients to choose the suitable materials for repair.Skin and soft tissue filling is mainly relying on local and free flaps and myocutaneous flap.At present,the common materials used for bone reconstruction include: autogenously bone,titanium,tissue engineering bone,etc...Large areas of the chest wall defect usually need to consider using the patch to close the chest.The key factors of recovery after the reconstruction of the chest wall were selected.Adipose Stem cells(ASCs)is a kind of mesenchymal stem cells,which is obtained from the fat.It has the capability to three differentiations,in inducing factor under different differentiation into a variety of cells,and can secrete a variety of cytokines.ASCs can accelerate wound healing through a variety of mechanisms,including paracrine effects,multilineage differentiation and angiogenesis etc.POC researched in recent years,is a kind of biological elastic material,has good biocompatibility and controllable mechanical effect,POC in the synthesis process of environmental requirements is not high,even at 37 s? can be synthesized,which makes POC materials and drug or protein combine to become complex,is a kind of ideal tissue engineering repair materials.This experiment adopts the POC material as the main body,with the same proportion of PLA,by electrostatic spinning technology was spun with 3D nano pore structure of the patch.Stem cell membrane technology to reduce the patch of pleural adhesions,promote the reconstruction of the chest wall.Part ?.Isolation and identification of rabbit adipose derived stem cellsMethod:Select female New Zealand rabbits,weighing about 2-2.5kg,after the ear edge vein injection anesthesia,take neck and back fat mass,fat mass cut into pieces after the addition of I type collagenase digestion centrifugal separation.Using isolated using inverted microscope to observe the general morphology;flow cytometry to detect CD29,CD44,CD90,CD31 and CD45,cell surface marker;MTT assay and cell counting method to measure stem cell proliferation curve;r ACSs osteogenic and into cartilage,adipogenic differentiation are carried out respectively,and alizarin red,alcian blue,oil red o specific staining.Results:The first three generations of r ASCs have higher purity and activity,and can be used as seed cells for tissue engineering experiments.Part ?.Establishment of POC-PLA Electro Spinning Patch Combined with ASCs and Material Security DetectionMethod:The massage to the molar ratio of 1:1 will citric acid and 1,octane diol was prepared POC prepolymer,trifluoro ethanol as solvent,according to the quality ratio of 1:1 ratio of preparation of POC pre poly body and the PLA solution,electric spinning after curing obtain patch using thermo sensitive culture dish will be using diaphragm transferred to patch formed on the surface of the composite patch.Scanning electron microscopy was used to detect the micro morphology,three-dimensional pore structure,and the adhesion of stem cells.Material properties were below the detection: mechanical properties testing.The PBS culture detection of the degradation rate;mixed cell culture to detect cell proliferation,adhesiveness and cytotoxicity;rat abdominal wall subcutaneous implantation were observed in the local inflammatory reaction,detection of tissue compatibility.Results:POC-PLA has no cytotoxicity,no obvious inflammatory reaction in vivo,ASCs along the uniform material growth,is a promising biomaterial.Part ?.Reconstruction of Full Thickness Chest Wall Defects in Rabbits by POC-PLA Electro Spinning Patch Combined with ASCsMethod:Select 65 healthy New Zealand rabbits were randomly divided into group A,group B,group C and group D,e group four groups.A group of e PTFE patch repair group,group B for simple flap repair group,group C as POC+PLA patch repair group,group D cell composite membrane POC+PLA fill piece repair group,e group sham operation group.X-ray film of the chest wall,lung function,respectively at postoperative 4 weeks,12 weeks,24 weeks to take tissue samples,and the observation of the pleural adhesions sample organization detection and CD31 immunohistochemistry detection,Western blot was used to detect the expression of vascular endothelial growth factor(VEGF)were observed in each group after.Results:(1)POC-PLA patch can be used as a biodegradable patch for tissue engineering chest wall repair.(2)ASCs can reduce the POC-PLA diaphragm in the chest wall reconstruction and the lung adhesion.(3)POC-PLA ASCs patch is a promising material for chest wall reconstruction after good pulmonary function,and reduce the complications such as pleural adhesion.