Determining the effectiveness of a xenogeneic bone matrix decellularization protocol in <i>in vitro</i> and <i>in vivo</i> studies

Abstract

BACKGROUND: Restoration of tissue integrity, including bone tissue, is currently an extremely urgent task, both because of the increasing number of high-energy traumas accompanied by severe skeletal injuries and the growing number of revision endoprosthetics requiring the use of bone-plastic materials. AIM: To determine the efficacy of the developed protocol for decellularization of xenogenic bone matrix in preclinical in vitro studies aimed at defining the purification matrix degree, on the basis of histological, microtomographic evaluation, cell culture method, and in vivo studies aimed at identifying the biocompatibility and osteogenic properties of the materials. MATERIALS AND METHODS: Xenogenic spongiosis tissue of bovine femoral bones was fragmented to the size of 10×10×10 mm and treated with water, hypotonic solution and 3% hydrogen peroxide solution, deep purification by supercritical fluid extraction was applied. The efficiency of the optimal protocol was tested in vitro by cell culture method and in vivo. RESULTS: The ideal interaction of cell culture with bone-plastic material was revealed, which may be associated with the absence of cytotoxic substances in the matrix, optimal roughness and good adhesive properties of the surface suitable for the formation of focal contacts by bone marrow stromal cells, their adhesion, spreading and proliferation. A pronounced bone callus with formed bone bridges running along the surface of the implanted material was determined 30 days after implantation. By this study period, the defect was practically closed due to the intermedial bone callus, the implanted material is found in the form of individual small osteocyte-free fragments. CONCLUSIONS: The xenogenic bone matrix purified according to the developed protocol is bio- and cytocompatible, has pronounced osteoconductive properties, effectively stimulates regenerative osteogenesis in living organism.