Biofunctional Materials and Devices Research Group, National Metal and Materials Technology Center, 114 Thailand Science Park, Phahonyothin Road, Klong Luang, Pathum Thani 12120, Thailand.
Assistive Technology and Medical Devices Research Center, Central Office, 111 Thailand Science Park, Phahonyothin Road, Klong Luang, Pathum Thani 12120, Thailand.
ACS Appl Bio Mater. 2022 Jun 20;5(6):2689-2702. doi: 10.1021/acsabm.2c00161. Epub 2022 May 20.
This study was aimed to evaluate the chondrogenic differentiation of human mesenchymal stem cells (hMSCs) and polarization of THP-1-derived macrophages cultured on poly(ε-caprolactone) (PC)/poly(3-hydroxybutyrate--3-hydroxyvalerate) (PH) blended scaffolds with dual primary (PP) and secondary (SP) pores, which were fabricated via a 3D printing technique, i.e., fused deposition modeling, followed by a salt-leaching process at 50 °C for varied times, i.e., 15, 30, and 60 min. Sodium chloride (SC), a porogen, was initially incorporated in the blend at varied weight percentages, i.e., 0, 25, and 50%, whereas 1 M NaOH solution and deionized water were used as salt-leaching agents. To elucidate the surface properties of the developed scaffolds, directly governed by the amount of the salt originally mixed and the salt-leaching efficiency, several characterization techniques, e.g., scanning electron microscopy, X-ray microcomputed tomography, mercury intrusion porosimetry, atomic force microscopy, and contact angle measurement, were used. Meanwhile, the salt-leaching efficiency was determined by means of weight loss measurement and thermogravimetric analysis. It was found that the alkaline solution could satisfactorily leach out the salt particles in 60 min with a mild etching of the polymer framework. The most immensely and homogeneously pitted filament surface was observed in the NaOH-treated scaffold initially integrated with 50% salt, i.e., 60B_PC/PH/50SC; the SP structure was mostly open and interconnected. The size of most of micropores was about 0.14 μm. With its suitable microsurface roughness and hydrophilicity, 60B_PC/PH/50SC could properly support the initial attachment and lamellipodia formation of hMSCs, which was favorable for chondrogenesis. Consequently, a significantly increased ratio of glycosaminoglycans/deoxyribonucleic acid and a superior expression of the COL2A1 gene were detected when cells were grown on this material. Although 60B_PC/PH/50SC induced the macrophages to secrete a slightly high level of IL-1β during the first few days of culture, the polarized M1 cells could return to a nearly normal stage at Day7, suggesting no unfavorable chronic inflammation caused by the material.
本研究旨在评估人骨髓间充质干细胞（hMSCs）在聚（ε-己内酯）（PC）/聚（3-羟基丁酸-3-羟基戊酸）（PH）共混支架上的软骨分化和 THP-1 衍生巨噬细胞的极化，该支架具有双初级（PP）和次级（SP）孔，通过 3D 打印技术，即融合沉积建模，然后在 50°C 下进行不同时间的盐浸提，即 15、30 和 60min。在共混物中最初加入不同重量百分比的氯化钠（SC）作为造孔剂，即 0、25 和 50%，而 1M NaOH 溶液和去离子水用作盐浸提剂。为了阐明由最初混合的盐量和盐浸提效率直接控制的开发支架的表面性质，使用了几种表征技术，例如扫描电子显微镜、X 射线微计算机断层扫描、压汞孔隙率、原子力显微镜和接触角测量。同时，通过重量损失测量和热重分析来确定盐浸提效率。结果发现，碱性溶液可以在 60min 内将盐颗粒满意地浸出，同时对聚合物框架进行轻微蚀刻。在最初加入 50%盐的 NaOH 处理支架中观察到最广泛和均匀的凹坑丝状表面，即 60B_PC/PH/50SC；SP 结构大多是开放和相互连接的。大多数微孔的尺寸约为 0.14μm。60B_PC/PH/50SC 具有合适的微表面粗糙度和亲水性，可以适当支持 hMSCs 的初始附着和伪足形成，有利于软骨形成。因此，当细胞在这种材料上生长时，检测到糖胺聚糖/脱氧核糖核酸的比例显著增加，并且 COL2A1 基因的表达也更好。尽管 60B_PC/PH/50SC 在培养的最初几天诱导巨噬细胞分泌稍高水平的 IL-1β，但极化的 M1 细胞在第 7 天可以恢复到几乎正常的状态，这表明该材料不会引起不利的慢性炎症。
