Study On The Construction And Performance Of Tissue Engineering Periosteal With BMP-2 And VEGF Sustained Release Function

Purpose:To prepare a new type of tissue engineering periosteum,we chose to use Poly L-lactic acid(PLLA),polydopamine(PDA)coating,bone morphogenetic protein-2(BMP-2)and vascular endothelial growth factor(VEGF).The artificial periosteum is suitable for evaluating the ability of human bone marrow mesenchymal stem cells(hBM-MSCs)to adhere and proliferate and promote their differentiation into bone.Method:A self-assembled electrospinning device was used to prepare PLLA nanofiber membrane.PDA coating formed on the surface of PLLA membrane after that PLLA membrane and PDA reacted in weak alkaline solution protected from light.Then immerse the PDA/PLLA membrane in the BMP-2 and VEGF solution at the target concentration and shake for 4 hours at room temperature to obtain the BMP-2/VEGF/PDA/PLLA membrane.Scanning electron microscopy(SEM)and immunofluorescence were used to detect its characterization;enzyme linked immunosorbent assay(ELISA)was used to evaluate its ability to release BMP-2 and VEGF;real-time quantitative polymerase chain reaction(RT-qPCR),Western Blot(WB)experiment,Alizarin staining was used to detect its ability to induce osteogenic differentiation.The cell compatibility and cytotoxicity were tested by cellular immunofluorescence and MTS in vitro cell culture.In vivo experiments,the bone defect model was constructed where the materials implanted in,and the bone formation was detected by Micro CT.Results:We have successfully prepared BMP-2/VEGF/PDA/PLLA membranes,which has the function of releasing BMP-2 and VEGF slowly.The prepared artificial periosteum has no cytotoxicity,great cell compatibility and can induce osteogenic differentiation.The results of in vitro experiments prove that it has good osteogenesis.Conclusion:The PLLA membrane prepared by electrospinning has a good microstructure and can be used as a scaffold for periosteal tissue engineering.The PDA coating can help the PLLA membrane loading VEGF and BMP-2,increasing the hydrophilicity of the PLLA membrane to benefit hBM-MSCs adhere and proliferation.The prepared artificial bionic periosteum has good osteo-induction effect,and has better osteogenic effect under the synergistic effect of loading VEGF and BMP-2.