Treatment of osteonecrosis of the femoral head using prevascularized bone tissues constructed with human umbilical cord mesenchymal stem cells and human umbilical vein endothelial cells

Abstract Background： Studies have shown that osteonecrosis of the femoral head (ONFH)is related to bone marrow mesenchymal stem cell injury and microvascular injury. Early ONFH patients can choose core decompression and other treatments, but the clinical effect is poor. In recent years, tissue engineering technology based on mesenchymal stem cells is a new method to treat ONFH. In addition, whether the transplantation area is fully vascularized also affects whether the mesenchymal stem cells can play a repair role. In this study, we constructed prevascularized bone tissue based on human umbilical cord mesenchymal stem cells and human umbilical vein endothelial cells to evaluate the therapeutic effect of prevascularized bone tissue on ONFH. Objective: This paper is to investigate the effect of pre-vascularized bone tissue constructed by human umbilical cord mesenchymal stem cells and human umbilical vein endothelial cells on bone repair of necrotic femoral head, so as to provide theoretical basis for clinical treatment of necrotic femoral head. Methods: The rabbits were randomly divided into 5 groups, of which, 1 group was not given any intervention, while rabbit femoral head necrosis models were prepared for the other 4 groups by microwave heating method and they are respectively named mould-making group, static bone tissue group, dynamic bone tissue group and pre-vascularized bone tissue group according to the different substances injected into the femoral head. Various tests, including MRI, Micro-CT, HE staining and immunofluorescence staining, were performed after the animals were executed 8 weeks after treatment to assess the osteogenic ability of the implant and the repair effect of necrotic femoral head. Results: Various tests showed that the pre-vascularized bone tissue group had better ability to promote necrotic femoral head repair, and significant new bone formation and bone quality improvement occurred 8 weeks after surgery. The static bone tissue group and dynamic bone tissue group were similar in their ability to promote femoral head repair, with all the three groups outperforming the modeled group. Conclusions: The pre-vascularized bone tissue has a good effect on promoting the reconstruction of necrotic femoral head and shows superior osteogenesis, angiogenesis and bone repair effect. It is thus a good graft material for repairing necrotic femoral head and is of great value in the treatment of necrotic femoral head.