以个性化、结构可控的3D打印支架为基础的骨组织工程技术是大体积骨缺损修复领域新的研究热点。而细胞在材料表面粘附是这一技术的成功关键之一。课题组研究证实：人唾液来源的组胺素（Hst1）及其衍生物可高效促进上皮、内皮细胞在多种材料表面粘附、铺展和迁移。与表面修饰方式相比，Hst1可与细胞直接混合，高效快速促进细胞粘附，因而对不同打印材料具有广泛适用性。课题组预实验显示：Hst1在低活性表面也能显著促进成骨前体细胞铺展。然而Hst1促进间充质干细胞（MSCs）在3D打印支架表面粘附、铺展、迁移效果及其信号机制尚未明确。本项目中，课题组将1）体外、体内检测干细胞在3D打印支架上粘附、迁移及存活率，筛选出最优Hst1剂量；2）利用通路蛋白芯片、western等分子生物学手段，揭示 Hst1作用机制；3）体内验证Hst1/MSC-3D打印支架修复大体积骨缺损效果。为其临床应用提供理论依据和实验基础。

The customized 3D-priting-based bone tissue engineering is one of the hottest research focus in the field of the repair of large bone defects. The attachment of cells on the scaffold surface is one of the key factors for successful bone regeneration. Our preliminary research has proved that histantin-1(Hst1) and its deviations can effectively improve the attachment, spreading and migration of epithelial and endothelial cells on various scaffold materials. Compare to other techniques for surface modification, Hst1 can be mixed with cells directly and enhance cell attachment with high efficiency. Our pilot study showed that Hst1 can improve the spreading of pre-osteoblasts even on surfaces with low activity. However, it is still not clear that the effect of Hst1 on improving the attachment, spreading and migration of mesenchymal stem cells on 3D-printing scaffold. The aim of this project is to construct a histantin-1(Hst1)-modified 3D-priting scaffold to repair large bone defect, to evaluate its efficacy for bone regeneration and to explore the signaling pathway and molecular mechanism. Firstly, we will test the effect of Hst1 on the adhesion of mesenchymal stem cell on scaffolds in vitro, so as to optimize the Hst1 dosage on per unit scaffolds; and evaluate the efficacy of repairing large bone defect in vivo. Secondly, we will assess the influence of Hst1-modified 3D-priting scaffold on the loading efficiency of stem cells in vitro and success rate and migration of stem cells in vivo. Thirdly, we will explore the signal pathway and molecular mechanism of how Hst1 regulate the adhesion of stem cells on scaffolds. This project will provide a new strategy for improving the adhesion of mesenchymal stem cells-3D-priting scaffold in bone tissue engineering, and make great benefits for its clinical transformation.