A comparative study of autogenous, allograft and artificial bone substitutes on bone regeneration and immunotoxicity in rat femur defect model

Abstract

Repair and reconstruction of large bone defect were often difficult, and bone substitute materials, including autogenous bone, allogenic bone and artificial bone, were common treatment strategies. The key to elucidate the clinical effect of these bone repair materials was to study their osteogenic capacity and immunotoxicological compatibility. In this paper, the mechanical properties, micro-CT imaging analysis, digital image analysis and histological slice analysis of the three bone grafts were investigated and compared after different time points of implantation in rat femur defect model. Autogenous bone and biphasic calcium phosphate particular artificial bone containing 61.4% HA and 38.6% β-tricalcium phosphate with 61.64% porosity and 0.8617 ± 0.0068 g/cm3 density (d ≤ 2 mm) had similar and strong bone repair ability, but autogenous bone implant materials caused greater secondary damage to experimental animals; allogenic bone exhibited poor bone defect repair ability. At the early stage of implantation, the immunological indexes such as Immunoglobulin G, Immunoglobulin M concentration and CD4 cells’ population of allogenic bone significantly increased in compared with those of autologous bone and artificial bone. Although the repair process of artificial bone was relatively inefficient than autologous bone graft, the low immunotoxicological indexes and acceptable therapeutic effects endowed it as an excellent alternative material to solve the problems with insufficient source and secondary trauma of autogenous bone.

Recent advances in regenerative biomaterials

“…Liang et al . [ 203 ] studied the difference of autogenous, allograft and artificial bone substitutes on bone regeneration, and suggested that the allogenic bone graft has relatively poor bone repair ability compared with autogenous and artificial bone substitutes probably due to the immunotoxicological reaction. This implies the immunogenicity of allogenic cells, and thus the necessity of removal of those cells.…”

In vitro comparison of the osteogenic capability of human pulp stem cells on alloplastic, allogeneic, and xenogeneic bone scaffolds

“…The cell transfer properties and treatment success depend on the physical properties of the bone graft substitute, including porosity, pore size [ 34 ], and pore interconnectivity [ 23 ]. Considering the influence of biomaterials on stem cell interactions, studies of stem cell–scaffold interactions in relation to proliferation and differentiation are essential components in the search for a favorable scaffold [ 35 , 36 ]. Many in vivo studies have investigated stem cell interactions with bone graft substitutes, and the ability to induce bone growth [ 14 , 36 ].…”

Coordination of Osteoblastogenesis and Osteoclastogenesis by the Bone Marrow Mesenchymal Stem Cell-Derived Extracellular Matrix To Promote Bone Regeneration

“…Bone defects associated with trauma, infection, and tumor are common clinical symptoms in orthopedics, which require frequent surgical intervention. In most treatments, bone substitutes, including autologous, allogeneic, and artificial bones, are usually required. , Although autologous and allogeneic bone grafts possess superior osteoconduction and osteoinduction, the risks of immune rejection, disease transmission, donor site complications, and limited supply hinder their clinical application. , Bone tissue engineering is a prospective approach to induce bone regeneration and repair. However, the introduction of supraphysiological exogenous growth factors, such as bone morphogenic protein-2 (BMP-2), vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF), may cause adverse effects like ectopic bone formation, vascular leakage, osteoclast activation, and osteolysis. − …”

“…In most treatments, bone substitutes, including autologous, allogeneic, and artificial bones, are usually required. 1,2 Although autologous and allogeneic bone grafts possess superior osteoconduction and osteoinduction, the risks of immune rejection, disease transmission, donor site complications, and limited supply hinder their clinical application. 3,4 Bone tissue engineering is a prospective approach to induce bone regeneration and repair.…”