Experimental Study Of Vascularized Tissue Engineered Bone Packed By The Greater Omentum

Objective To explore the ability of using vascularized tissue engineered bone packed by the greater omentum to repair bone long bone defect, and assess the feasibility and quality of tissue engineering bone packed by the greater omentum to repair long bone defects. It will supply and supplement experimental basis for tissue engineering bone in clinical applications.Methods Bone marrow was harvested from the shaft of femur and tibial of New Zealand white rabbits.Bone marrow mesenchymal stem cells were separated and cultured by using the whole bone marrow adherent culture method and purified by exchanging of culture medium combining with cell passaging.It was identified through viewing cell morphology, multilineage differentiation and the cell morphological changes before and after osteoblastic identification under electron microscope.The cell proliferation of the third generation was detected by MTT method. Rabbit bone marrow mesenchymal stem cells after osteoblastic identification were inoculated into a homemade bio-derived bone scaffolds to construct tissue engineering bone in vitro. Tissue engineering bone were implanted into the radius defect of rabbits.All experimental animals were randomly divided into tissue engineered bone packed by the greater omentum group and tissue engineered bone group. Graft’s surface changes and the surrounding tissue reaction were observed in Different postoperative time points. After4weeks,8weeks,12weeks,X-ray examination was carried out in the bone defect. The general samples and histological examinatio were observed in order to assess the osteogensis and angiopoiesis of the grafts.Results After two sets of grafts implanted in the bone defect, the surgery wounds grew well and no significant toxicity and inflammatory responses were found. The incision was primary healing in each animal. After12weeks, X-ray showed that the implants and host bone is almost healed in greater omentum group.While simple group after12weeks was not satisfied with bone healing. The gray value of grafts in the the greater omentum group was higher than simple tissue engineering bone group.The difference was statistically significant (P<0.05); after4weeks,8weeks,12weeks,by comparing the results of bone tissue slices,it indicated that newborn bone trabecular area in the greater omentum group was significantly higher than simple tissue engineering bone group.the difference was statistically significant (P<0.01); It also indicated that neovascular area of the greater omentum group were higher than simple tissue engineering bone group at the same time point (P<0.05), the difference was statistically significant.Conclusions The greater omentum has a rich vascular network.tissue engineered bone packed by the greater omentum was implanted into bone defect.It not only promoted vascularization of tissue engineered bone and osteogensis, but alao improved the quality of tissue engineered to repair bone defects.