CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, Aveiro, Portugal.
Centro de Química Estrutural and Department of Chemical Engineering, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
Biofabrication. 2021 Apr 7;13(3). doi: 10.1088/1758-5090/abdc86.
Leveraging 3D bioprinting for processing stem cell-laden biomaterials has unlocked a tremendous potential for fabricating living 3D constructs for bone tissue engineering. Even though several bioinks developed to date display suitable physicochemical properties for stem cell seeding and proliferation, they generally lack the nanosized minerals present in native bone bioarchitecture. To enable the bottom-up fabrication of biomimetic 3D constructs for bioinstructing stem cells pro-osteogenic differentiation, herein we developed multi-bioactive nanocomposite bioinks that combine the organic and inorganic building blocks of bone. For the organic component gelatin methacrylate (GelMA), a photocrosslinkable denaturated collagen derivative used for 3D bioprinting was selected due to its rheological properties display of cell adhesion moieties to which bone tissue precursors such as human bone marrow derived mesenchymal stem cells (hBM-MSCs) can attach to. The inorganic building block was formulated by incorporating mesoporous silica nanoparticles functionalized with calcium, phosphate and dexamethasone (MSNCaPDex), which previously proven to induce osteogenic differentiation. The newly formulated photocrosslinkable nanocomposite GelMA bioink incorporating MSNCaPDex nanoparticles and laden with hBM-MSCs was successfully processed into a 3D bioprintable construct with structural fidelity, and well dispersed nanoparticles throughout the hydrogel matrix. These nanocomposite constructs could induce the deposition of apatite, thus showing attractive bioactivity properties. Viability and differentiation studies showed that hBM-MSCs remained viable and exhibited osteogenic differentiation biomarkers when incorporated in GelMA/MSNCaPDex constructs and without requiring further biochemical, nor mechanical stimuli. Overall, our nanocomposite bioink has demonstrated excellent processability via extrusion bioprinting into osteogenic constructs with potential application in bone tissue repair and regeneration.
利用 3D 生物打印处理干细胞负载的生物材料为骨组织工程制造具有生命力的 3D 结构开辟了巨大的潜力。尽管迄今为止已经开发了几种生物墨水，它们显示出适合干细胞接种和增殖的合适理化性质，但它们通常缺乏天然骨生物结构中存在的纳米级矿物质。为了能够自下而上制造仿生 3D 结构来生物指导干细胞向成骨细胞分化，本文开发了多功能生物活性纳米复合生物墨水，将骨的有机和无机构建块结合在一起。对于有机成分明胶甲基丙烯酰（GelMA），选择了光交联的变性胶原衍生物，因为其流变性质显示出细胞附着部分，骨组织前体细胞，如骨髓间充质干细胞（hBM-MSCs）可以附着在这些部分上。无机构建块是通过掺入具有钙、磷和地塞米松的介孔硅纳米粒子（MSNCaPDex）来配制的，以前的研究证明该纳米粒子可以诱导成骨细胞分化。新配方的光交联纳米复合 GelMA 生物墨水，其中包含 MSNCaPDex 纳米粒子并负载 hBM-MSCs，可以成功地加工成具有结构保真度的 3D 可生物打印构建体，并且纳米粒子在水凝胶基质中均匀分散。这些纳米复合结构可以诱导磷灰石的沉积，从而显示出吸引人的生物活性特性。活力和分化研究表明，当 hBM-MSCs 掺入 GelMA/MSNCaPDex 构建体中时，它们仍然具有活力并表现出成骨细胞分化生物标志物，而无需进一步的生化或机械刺激。总体而言，我们的纳米复合生物墨水通过挤出生物打印表现出优异的可加工性，具有在骨组织修复和再生中应用的潜力。
