Tianjin Medical University School and Hospital of Stomatology, Tianjin, China (mainland).
Department of Cell Biology, 2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Medical Epigenetics, Tianjin Medical University, Tianjin, China (mainland).
Med Sci Monit. 2019 Apr 11;25:2658-2671. doi: 10.12659/MSM.914269.
BACKGROUND To fabricate strontium (Sr)-incorporated titanium (Ti) surfaces by a novel 1-step phase-transited lysozyme (PTL) treatment, and investigate the effects of the prepared samples on osteogenesis and osteoimmunoregulation. MATERIAL AND METHODS Five groups of titanium specimens were prepared, including Ti, PTL, PTL@10Sr (PTL coating with 10 mg/mL Sr), PTL@20Sr PTL coating with 20 mg/mL Sr), and PTL@50Sr (PTL coating with 50 mg/mL Sr) groups. Behaviors of bone marrow mesenchymal stem cells (BMSCs) such as initial attachment, spread, proliferation, and migration, on different surfaces were examined by immunofluorescence, MTS assay, and Transwell system. Then the osteogenic differentiation of BMSCs was detected. When an immune response was factored in, the polarization of macrophages induced by the prepared surfaces was detected by real-time PCR, and the response of BMSCs to macrophage-conditioned medium was assessed in terms of cell migration and osteogenic differentiation. Finally, an in vivo study was performed, using the rat femora implant model, to evaluate the potential for osteogenic induction and osteoimmunoregulation of materials. RESULTS Our in vitro experiments indicated that PTL coating could improve cell spread and adhesion, and the stable Sr release of PTL@Sr layers could promote cell migration and osteogenesis. Moreover, PTL@Sr surface could regulate the immune response of macrophages resulting in enhanced BMSCs recruitment and osteogenic differentiation. The in vivo evaluation showed less inflammatory infiltration and improved bone formation in the PTL@20Sr group. CONCLUSIONS The Sr-loaded PTL layers have greater potential for the induction of osteogenic differentiation of BMSCs, meanwhile Sr-loaded PTL layers could adjust the immune response and thus promote osteogenesis both in vitro and in vivo.
通过一种新颖的 1 步相转变溶菌酶（PTL）处理来制造锶（Sr）掺入的钛（Ti）表面，并研究制备样品对成骨和骨免疫调节的影响。
制备了包括 Ti、PTL、PTL@10Sr（PTL 涂层含 10mg/mL Sr）、PTL@20Sr（PTL 涂层含 20mg/mL Sr）和 PTL@50Sr（PTL 涂层含 50mg/mL Sr）五组钛样品。通过免疫荧光、MTS 测定和 Transwell 系统检测不同表面骨髓间充质干细胞（BMSCs）的初始附着、伸展、增殖和迁移等行为。然后检测 BMSCs 的成骨分化。当考虑免疫反应时，通过实时 PCR 检测制备表面诱导的巨噬细胞极化，并根据细胞迁移和成骨分化评估 BMSCs 对巨噬细胞条件培养基的反应。最后，使用大鼠股骨植入模型进行体内研究，评估材料的成骨诱导和骨免疫调节潜力。
我们的体外实验表明，PTL 涂层可以改善细胞伸展和粘附，PTL@Sr 层的稳定 Sr 释放可以促进细胞迁移和成骨。此外，PTL@Sr 表面可以调节巨噬细胞的免疫反应，从而增强 BMSCs 的募集和成骨分化。体内评价表明，PTL@20Sr 组的炎症浸润较少，骨形成改善。
负载 Sr 的 PTL 层在诱导 BMSCs 成骨分化方面具有更大的潜力，同时负载 Sr 的 PTL 层可以调节免疫反应，从而在体外和体内都促进成骨。
