State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing 100029, PR China.
Department of Spine Surgery, Beijing Jishuitan Hospital, Beijing 100035, PR China.
Mater Sci Eng C Mater Biol Appl. 2019 Jul;100:862-873. doi: 10.1016/j.msec.2019.02.079. Epub 2019 Mar 20.
Mineralization capability is an important issue in developing bone repairing biomaterials, while it is not quite clear how this feature would act in the presence of cells and influence cell osteogenic differentiation without adding extra osteoinductive factors such as β‑sodium glycerophosphate and dexamethasone. Poly(l‑lactide) (PLLA) and gelatin composite fibers (PG, 1:1 in weight) were electrospun, treated with CaCl solution (PG-Ca), and used for mineralization studies by using cell culture media (αMEM, and αMEM + serum). Bone mesenchymal stromal cells (BMSCs) were then seeded and cultured on both PG and PG-Ca fibrous mats for 28 days by only using αMEM + serum. Interestingly, mineral depositions on both PG and PG-Ca fibers were detected in the environment of αMEM or αMEM + serum, in which, PG-Ca fibers demonstrated stronger ability in inducing hydroxyapatite formation than PG fibers, especially in the presence of fetal bovine serum. When BMSCs were cultured on the two kinds of fibrous mats, apatite depositions were still clearly detected, while the depositing amounts decreased in comparison with corresponding cell-free cases. It was ascribed to the consumption of ions by the continuously proliferating BMSCs, whose osteogenic differentiation was significantly promoted even without extra osteoinductive factors, especially on PG-Ca fibrous mats, in comparison with the control group. Therefore, it was confirmed the capability of scaffolding materials in enriching ions like calcium and phosphate around cells was an efficient way to promote bone regeneration.
矿化能力是开发骨修复生物材料的一个重要问题，然而，在细胞存在的情况下，以及在不添加额外的成骨诱导因子（如β-甘油磷酸钠和地塞米松）的情况下，这种特性如何作用并影响细胞成骨分化，目前还不是很清楚。聚（L-丙交酯）（PLLA）和明胶复合纤维（PG，重量比为 1:1）通过静电纺丝制备，用 CaCl 溶液处理（PG-Ca），然后使用细胞培养液（αMEM 和αMEM+血清）进行矿化研究。随后，将骨髓间充质基质细胞（BMSCs）接种在 PG 和 PG-Ca 纤维垫上，并仅使用αMEM+血清培养 28 天。有趣的是，在αMEM 或αMEM+血清的环境中，均在 PG 和 PG-Ca 纤维上检测到了矿化沉积，其中 PG-Ca 纤维在诱导羟基磷灰石形成方面的能力强于 PG 纤维，尤其是在胎牛血清存在的情况下。当 BMSCs 培养在这两种纤维垫上时，仍能清楚地检测到磷灰石沉积，而与相应的无细胞对照相比，沉积量减少。这归因于不断增殖的 BMSCs 对离子的消耗，其成骨分化明显得到促进，即使没有额外的成骨诱导因子，尤其是在 PG-Ca 纤维垫上，与对照组相比。因此，证实支架材料在细胞周围富集钙和磷酸盐等离子的能力是促进骨再生的一种有效方法。
