Research On Cell Biocompatibility Of New-type Nanofiber Scaffold For Tissue Engineering

Tissue engineering scaffolds have been widely used for congenital and acquired cardiovascular surgery treatment. At present, the morbidity of coronary atherosclerotic heart disease has been present an increasing trend.The coronary artery bypass graft bypass is still the main therapy method. Surgeons mainly use autologous veins and (or) arterial as graft material in the operation. But some patients don't own appropriate autologous blood vessels for transplanting, limit the blood vessel transplantation. As a common heart disease, the treatment of some congenital heart disease such as Tetralogy of Fallot, aortic coarctation, ventricular septal defect, atrial septal defect need the scaffold to reconstruct or repair the stenosis or defects parts. Patients patched with autologous pericardial patch often occur restenosis during postoperative healing process, whith mainly because of cellulose deposition and connective tissue homogeneous appearance changes, the pericardial patch endothelial change, especially the patch fibrosis. After patching with the traditional artificial synthetic materials, due to the postoperative immune rejection, anastomotic hyperplasia, thrombosis, and it won't grow with the children, and it will be long-term stored in body,which may lead to potential problems, and the long-term patency rate reduced, lead to limit the application in the clinical therapy. Therefore, it is quite meaning to have the emergence of biological macromolecular,whitch owns the regenerative potential and it can replace autologous for patching during cardiovascular surgery.In this experiments we primarily cultured the rabbit aorta smooth muscle cells in vitro and transplant the rabbit aorta vascular smooth muscle cells on traditional stents and high porosity nanofiber stents.And then compare the cellular compatibility through the cell morphology, cell adhension rate, proliferation. It can provide theoretical basis for the preparation of new cardiovascular stents.Part one culture of vascular smooth muscle cell of rabbit aortaObjective:To provide seeding cells for new polycaprolactone(PCL) nanofiber bracket cell Biocompatibility of new-type nanofiber Scaffold tissue engineering research.Methods:Aortas of rabbits must be excised rapidly when the rabbits are under anesthesia,and keep the aortas germfree. The vascular smooth muscle cells were cultured by tissue explant method. We can use inverted phase contrast microscope, transmission elctron microscope(TEM) and immunohistochemical staining to observe and and identified the cells morphological ,structure,characteristics,and recognize the cells'type.Results:We have successfully primary cultured vascular smooth muscle cells and subcultured them. During the process,we can observe the cells under phase-contrast microscope and transmission elctron microscope(TEM).Vascular smooth muscle cells show"hill -vale"appearance,and the cells show much of"myofilament"under TEM.Through immunohistochemical staining we can observe that theα-actin in the smooth muscle cells.Conclusion:In this reseach we succsessfully cultured vascular smooth muscle cells which can be applied as seed cells during the next research on cell biocompatibility of new-type nanofiber scaffold.Part two Research on cell Biocompatibility of new-type nanofiber ScaffoldObjective:The aim of this study was to evaluate the cell biocompatibility of high porosity PCL scaffold made by electrostatic spinning technology. We transplanted the seed cells which has been cultured in the last research. And then evaluate the cells adhension and proliferation by WST-1 method. The cells morphology and proliferation also be observed though SEM to evaluate the cell biocompatibility of the scaffold.Methods:To evaluate the scaffolds cell biocompatibility, WST-1 method was used to evaluate the effects of scaffold on the adhesion and proliferation of smooth muscle cells cultured with scaffolds. Light microscope and scanning electron microscope were used to observe the morphology of cells.Results:The new-type high porosity PCL scaffold exhibit no harmful effect on the morphology of the seed cells; the cells transplanted on the scaffolds has better adhension than the cells on the traditional scaffolds obviously(P<0.05); the proliferation of the seed cells on the new-type scaffolds is much better than the seed cells on the traditional scaffolds(P<0.05); the seed cells on the new-type scaffolds and the control groups have most the same metabolic activity which is much better than the cells on the traditional scaffolds(P<0.05); the seed cells transplanted on the new-type scaffolds spread better and has obvious advantage on proliferation. And the cells transplanted on the new-type scaffolds grows faster than the cells on the traditional scaffold.Conclusions:The high porosity PCL nanofiber stents produced by electrostatic spinning technology has the multistage aperture of the diameter size less than smooth muscle cells, which may be helpful for smooth muscle cell adhesion, proliferation, and may be facilitate to the adhesion protein's adhesion, oxygen and nutrients'transmission and metabolites'eduction. The structure plays a very important role in promoting seeded cells'adhesion, proliferation and differentiation regulation. Compared to traditional scaffold, the new-type scaffolds have an advantage on providing rabbit aorta smooth muscle cell with good temporary support environment for their adhesion and proliferation. The new-tpye scaffolds own the higher cell biocompatibility than the traditional scaffolds.