Biomaterials and Tissue Engineering Research Unit, School of AMME, The University of Sydney, Sydney, NSW 2006, Australia.
Biomaterials. 2010 Apr;31(12):3175-84. doi: 10.1016/j.biomaterials.2010.01.024. Epub 2010 Feb 1.
In this study we developed novel scaffolds through the controlled substitution and incorporation of strontium and zinc into a calcium-silicon system to form Sr-Hardystonite (Sr-Ca(2)ZnSi(2)O(7), Sr-HT). The physical and biological properties of Sr-HT were compared to Hardystonite (Ca(2)ZnSi(2)O(7)) [HT]. We showed that Sr-HT scaffolds are porous with interconnected porous network (interconnectivity: 99%) and large pore size (300-500 microm) and an overall porosity of 78%, combined with a relatively high compressive strength (2.16+/-0.52 MPa). These properties are essential for enhancing bone ingrowth in load-bearing applications. Sr-HT ceramic scaffolds induced the attachment and differentiation of human bone derived cells (HOB), compared to that for the HT scaffolds. Sr-HT scaffolds enhanced expression of alkaline phosphatase, Runx-2, osteopontin, osteocalcin and bone sialoprotein. The in vivo osteoconductivity of the scaffolds was assessed at 3 and 6 weeks following implantation in tibial bone defects in rats. Histological staining revealed rapid new growth of bone into the pores of the 3D scaffolds with the Sr-HT and HT, relative to the beta-tricalcium phosphate (beta-TCP). In vivo, HT and Sr-HT produced distinct differences in the patterns of degradation of the materials, and their association with TRAP positive osteoclast-like cells with HT appearing more resistant compared to both Sr-HT and beta-TCP.
在这项研究中,我们通过将锶和锌受控取代和掺入钙-硅体系中,开发了新型支架,形成 Sr-Hardystonite(Sr-Ca(2)ZnSi(2)O(7),Sr-HT)。我们比较了 Sr-HT 的物理和生物学性质与 Hardystonite(Ca(2)ZnSi(2)O(7))[HT]。我们表明 Sr-HT 支架具有多孔性,具有相互连接的多孔网络(连通性:99%)和较大的孔径(300-500 微米),整体孔隙率为 78%,同时具有相对较高的抗压强度(2.16+/-0.52 MPa)。这些特性对于增强在承重应用中的骨长入是必不可少的。与 HT 支架相比,Sr-HT 陶瓷支架诱导了人源性骨衍生细胞(HOB)的附着和分化。Sr-HT 支架增强了碱性磷酸酶、Runx-2、骨桥蛋白、骨钙素和骨涎蛋白的表达。在植入大鼠胫骨骨缺损 3 和 6 周后,评估了支架的体内成骨活性。组织学染色显示,与β-磷酸三钙(β-TCP)相比,3D 支架的孔中快速生长新骨,Sr-HT 和 HT 均如此。体内,HT 和 Sr-HT 对材料降解模式产生了明显的差异,其与 TRAP 阳性破骨细胞样细胞的关联,与 HT 相比,Sr-HT 和 β-TCP 均具有更高的抗降解性。