Effanga Victoria Effiong, Akilbekova Dana, Mukasheva Fariza, Zhao Xiao, Kalyon Dilhan M, Erisken Cevat
Department of Chemical and Materials Engineering, School of Engineering and Digital Sciences, Nazarbayev University, 010000 Astana, Kazakhstan.
Department of Chemical Engineering and Material Science, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
Gels. 2024 Nov 15;10(11):745. doi: 10.3390/gels10110745.
Osteochondral (OC) tissue plays a crucial role due to its ability to connect bone and cartilage tissues. To address the complexity of structure and functionality at the bone-cartilage interface, relevant to the presence of the tidemark as a critical element at the bone-cartilage boundary, we fabricated graded scaffolds through sequential 3D printing. The scaffold's bottom layer was based on a gelatin/oxidized alginate mixture enriched with hydroxyapatite (HAp) to create a rougher surface and larger pores to promote osteogenesis. In contrast, the upper layer was engineered to have smaller pores and aimed to promote cartilage tissue formation and mimic the physical properties of the cartilage. An electrospun ε-polycaprolactone (PCL) membrane with micrometer-range pores was incorporated between the layers to replicate the function of tidemark-a barrier to prevent vascularization of cartilage from subchondral bone tissue. In vitro cell studies confirmed the viability of the cells on the layers of the scaffolds and the ability of PCL mesh to prevent cellular migration. The fabricated scaffolds were thoroughly characterized, and their mechanical properties were compared to native OC tissue, demonstrating suitability for OC tissue engineering and graft modeling. The distance of gradient of mineral concentration was found to be 151 µm for grafts and the native OC interface.
骨软骨（OC）组织因其连接骨组织和软骨组织的能力而发挥着关键作用。为了解决骨 - 软骨界面处结构和功能的复杂性，这与作为骨 - 软骨边界关键元素的潮标存在相关，我们通过连续3D打印制造了梯度支架。支架的底层基于富含羟基磷灰石（HAp）的明胶/氧化海藻酸盐混合物，以创建更粗糙的表面和更大的孔隙来促进骨生成。相比之下，上层设计有较小的孔隙，旨在促进软骨组织形成并模拟软骨的物理特性。在两层之间加入了具有微米级孔隙的静电纺丝ε - 聚己内酯（PCL）膜，以复制潮标的功能——一种防止软骨下骨组织血管化进入软骨的屏障。体外细胞研究证实了细胞在支架各层上的活力以及PCL网阻止细胞迁移的能力。对制造的支架进行了全面表征，并将其力学性能与天然OC组织进行了比较，证明其适用于OC组织工程和移植建模。发现移植物和天然OC界面的矿物质浓度梯度距离为151 µm。
