Department of Mining and Materials Engineering, McGill University, Montreal, QC, Canada.
Biomaterials. 2011 Dec;32(34):8915-26. doi: 10.1016/j.biomaterials.2011.08.016. Epub 2011 Sep 3.
Plastically compressed dense collagen (DC) gels mimic the microstructural, mechanical, and biological properties of native osteoid. This study investigated the effect of hybridizing DC with osteoinductive nano-sized bioactive glass (nBG) particles in order to potentially produce readily implantable, and mineralizable, cell seeded hydrogel scaffolds for bone tissue engineering. Due to the high surface area of nBG and increased reactivity, calcium phosphate formation was immediately detected within as processed DC-nGB hybrid gel scaffolds. By day 3 in simulated body fluid, accelerated mineralization was confirmed through the homogeneous growth of carbonated hydroxylapatite on the nanofibrillar collagen framework. At day 7, there was a 13 fold increase in the hybrid gel scaffold compressive modulus. MC3T3-E1 pre-osteoblasts, three-dimensionally seeded at the point of nanocomposite self-assembly, were viable up to day 28 in culture. In the absence of osteogenic supplements, MC3T3-E1 metabolic activity and alkaline phosphatase production were affected by the presence of nBG, indicating accelerated osteogenic differentiation. Additionally, no cell-induced contraction of DC-nBG gel scaffolds was detected. The accelerated mineralization of rapidly produced DC-nBG hybrid gels indicates their potential suitability as osteoinductive cell delivery scaffolds for bone regenerative therapy.
塑性压缩的致密胶原 (DC) 凝胶模拟了天然类骨质的微观结构、力学和生物学特性。本研究探讨了将具有成骨诱导性的纳米级生物活性玻璃 (nBG) 颗粒与 DC 杂交的效果，以期能够制备出可植入和矿化的细胞接种水凝胶支架，用于骨组织工程。由于 nBG 的高表面积和增加的反应性，在处理后的 DC-nGB 杂化凝胶支架中立即检测到了磷酸钙的形成。在模拟体液中培养 3 天时，通过在纳米纤维胶原骨架上均匀生长碳酸羟基磷灰石，证实了加速矿化。到第 7 天，杂化凝胶支架的压缩模量增加了 13 倍。在纳米复合材料自组装点三维接种的 MC3T3-E1 前成骨细胞在培养中可存活至第 28 天。在没有成骨补充剂的情况下，nBG 的存在影响了 MC3T3-E1 的代谢活性和碱性磷酸酶的产生，表明其成骨分化加速。此外，未检测到 DC-nBG 凝胶支架的细胞诱导收缩。快速产生的 DC-nBG 杂化凝胶的加速矿化表明其作为骨再生治疗中具有成骨诱导性的细胞输送支架具有潜在的适用性。
