Angiogenesis and bone regeneration by allogeneic mesenchymal stem cell intravenous transplantation in rabbit model of avascular necrotic femoral head.

To explore the feasibility of allogeneic mesenchymal stem cells (MSCs) transplanted intravenously for angiogenesis and bone repair in a rabbit model of avascular necrosis of femoral head (ANFH).Forty-five rabbits were randomized into three groups: a blank control group (without treatment), a necrotic control group (ANFH induced but without therapy), and an MSC transplantation group (ANFH induced and treated with MSC transplantation). The biopsies, blood sampling, and imaging examinations were performed on each animal at different time points (2, 4, and 6 wk). To monitor angiogenesis and bone repair progress, examinations included real-time polymerase chain reaction, Western blot analysis, x-ray, computed tomography, Masson trichrome staining, picrosirius red staining, and immunohistochemical staining.Necrosis and bone collapse were observed in bilateral femoral heads of necrotic rabbits of the necrotic control group, whereas the femoral head morphology was generally restored in the MSC transplantation group. The mRNA levels of Cbfa1, BMP, VEGF, and OPN in bone tissue were significantly higher in the MSC transplantation group than in the necrotic control group. In addition, the total protein amount of Cbfa1 in the MSC transplantation group was also significantly higher than that in the necrotic control group (P < 0.05).Intravenous transplantation of allogeneic MSCs can promote vascular and bone regeneration in the necrotic region of the femoral head in a rabbit model of ANFH. The results of our study suggest that the intravenous transplantation of MSCs could be a potential and minimally invasive treatment option for ANFH patients.