Effect of using multipotent mesenchymal stromal cells in bone grafting with xenogenic biomaterials

Currently, there is a significant frequency of degenerative diseases of the spine after surgical interventions with the use of bone grafting, especially in elderly patients. The results of the research indicate that the use of stem cells is one of the promising areas to increase the efficiency of osseointegration. The aim of the study was to evaluate the effectiveness of osteogenesis in the conditions of using xenografts loaded with stem cells, as well as morphological features of osseointegration. Materials and methods. An experimental study was conducted on 22 male rabbits. 2 animals were used to obtain stem cells, the remaining animals were implanted with xenogenic bone–substituting material "Osteomatrix" in the iliac wing, of which 10 animals were implanted with a xenograft not populated with cells, and the other 10 animals were implanted with an identical xenograft populated with mesenchymal stromal cells. Withdrawal from the experiment was carried out on the 60th day after implantation. The material's examination was carried out using the methods of fluorescence and light microscopy. To assess the statistical significance of observed differences (evaluation of proliferation, neoangiogenesis and osseointegration) in the experimental and control groups, the Mann–Whitney U test was used with a critical significance of p ≤ 0.05. Results. When using an osteoplastic material that was not loaded with multipotent mesenchymal stromal cells within 60 days after surgery, osseointegration passes through indirect osteogenesis with formation of full-fledged bone tissue in the future, which increases the time of complete defect healing. In the case of using an osteomatrix loaded with multipotent mesenchymal stromal cells of the bone marrow, osteogenesis proceeds in a direct way with the formation of a full-fledged bone tissue. Osteomatrix loading with multipotent mesenchymal stromal cells stimulates neoangiogenesis and proliferative activity of the tissue, which promotes activation of bone tissue repair processes and stimulates the processes of xenograft osseointegration. Conclusions. The use of multipotent mesenchymal stromal cells in bone grafting using xenografts increases the efficiency of osseointegration by stimulating direct osteogenesis, increasing the activity of proliferation and angiogenesis.