Mesenchymal cells (MSCs) are an attractive option as seed cells for bioprinting. However, loss of stemness and undesired differentiation reduces their effectiveness. In this study, 12 nm bioactive nanoparticles (BNPs) which could release silicon (Si) ions were used to enhance the properties of alginate/gelatin hydrogel bioink to maintain MSC stemness. By specifically leveraging biochemical signals of BNPs, bioink with defined stiffness towards osteogenic and adipogenic potential, independent of pore structure, were designed by incorporating with different concentration of BNPs. These bioink were characterized by printability, mechanical and rheological properties as well as osteogenic and adipogenic potentials. Notably, the effect of 2% BNPs addition in alginate/gelatin hydrogel on MSC stemness maintenance was confirmed by the expression of stemness markers. At higher concentrations of BNPs (5%), printability is impacted by the gelling process. We further confirmed the enhanced stemness maintenance by sweat gland lineage commitment of bioprinted MSCs in vitro. Overall, our study proved that alginate/gelatin hydrogel bioink reinforced by BNPs in the optimal concentrations could retain MSC stemness as well as support MSC growth and prolong the desired differentiation. These findings may provide a new approach to achieve the ideal therapeutic potential of MSCs in 3D bioprinting application.

间充质细胞 (MSCs) 作为生物打印的种子细胞是一种有吸引力的选择。然而，干性的丧失和不希望的分化降低了它们的有效性。在这项研究中，可以释放硅 (Si) 离子的 12 nm 生物活性纳米粒子 (BNP) 被用来增强藻酸盐/明胶水凝胶生物墨水的特性，以保持 MSC 干性。通过专门利用 BNPs 的生化信号，通过掺入不同浓度的 BNPs，设计了具有确定的成骨和脂肪形成潜力刚度的生物墨水，与孔结构无关。这些生物墨水的特点是可印刷性、机械和流变特性以及成骨和成脂潜力。尤其，干性标志物的表达证实了在海藻酸盐/明胶水凝胶中添加 2% BNPs 对 MSC 干性维持的影响。在较高浓度的 BNP (5%) 下，可印刷性受到胶凝过程的影响。我们进一步证实了生物打印的 MSC 的汗腺谱系承诺增强的干性维持体外。总体而言，我们的研究证明，最佳浓度的 BNP 增强的海藻酸盐/明胶水凝胶生物墨水可以保持 MSC 干性，支持 MSC 生长并延长所需的分化时间。这些发现可能为实现 MSC 在 3D 生物打印应用中的理想治疗潜力提供一种新方法。