Department of Polymer Science and Engineering, Sichuan University, Chengdu, People's Republic of China.
Biomed Mater. 2012 Dec;7(6):065007. doi: 10.1088/1748-6041/7/6/065007. Epub 2012 Nov 27.
Bio-ceramic porous scaffolds used in bone tissue engineering are incorporated in vivo by a process of cellular in-growth, followed by cell-mediated degradation and replacement of these scaffolds, in which macrophages and osteoclasts play the key role. Calcium polyphosphate (CPP) is an inorganic polymeric bioceramic which has been increasingly studied as a bone graft. The solution-mediated chemical degradation of strontium-substituted calcium polyphosphate (SCPP) scaffolds is well established in vitro, but an in vitro model of cell-mediated SCPP scaffold degradation has not been investigated. Herein, RAW264.7 (a murine monocyte/macrophage cell line) and osteoclasts were cultured on CPP and SCPP scaffolds. The weight loss and release amount of Sr(2+), Ca(2+) and PO(4)(3-) in a degradation medium indicated that macrophages could accelerate the degradation of SCPP. According to the results from MTT assay and scanning electron microscopy, it was found that a low dose of strontium was beneficial to the proliferation of macrophages, while strontium inhibited the activity of osteoclasts. This study will aid in developing SCPP scaffolds for in vivo bone tissue engineering.
用于骨组织工程的生物陶瓷多孔支架通过细胞向内生长的过程在体内结合，随后由细胞介导降解和这些支架的替代，其中巨噬细胞和破骨细胞起着关键作用。聚磷酸钙 (CPP) 是一种无机聚合生物陶瓷，已越来越多地被研究作为骨移植物。体外已经很好地确立了锶取代的聚磷酸钙 (SCPP) 支架的溶液介导的化学降解，但尚未研究细胞介导的 SCPP 支架降解的体外模型。在此，RAW264.7（一种鼠单核细胞/巨噬细胞细胞系）和破骨细胞在 CPP 和 SCPP 支架上培养。降解介质中 Sr(2+)、Ca(2+) 和 PO(4)(3-) 的失重和释放量表明巨噬细胞可以加速 SCPP 的降解。根据 MTT 测定和扫描电子显微镜的结果，发现低剂量的锶有利于巨噬细胞的增殖，而锶抑制破骨细胞的活性。这项研究将有助于开发用于体内骨组织工程的 SCPP 支架。
