Hu Xinli, Hu Qingxi, Liu Suihong, Zhang Haiguang
Rapid Manufacturing Engineering Center, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China; Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200072, China.
Rapid Manufacturing Engineering Center, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, China; Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200072, China; National Demonstration Center for Experimental Engineering Training Education, Shanghai University, Shanghai 200444, China.
Int J Biol Macromol. 2024 Dec;283(Pt 1):137228. doi: 10.1016/j.ijbiomac.2024.137228. Epub 2024 Nov 3.
One of the key challenges in bone defects treatment is providing adequate and stable blood supply during new tissue regeneration. Mesenchymal stem cells (MSCs) and endothelial cells (ECs) have great potential to promote osteogenesis and angiogenesis during bone defect repair through paracrine effects, but their therapeutic efficacy depends on effective cellular assembly and delivery. In this work, we developed various microspheres with different pore sizes for multi-cellular delivery to enhance the angiogenic and osteogenic capability via combining microfluidic and gradient freeze-drying techniques. The particle and pore size of fabricated porous gelatin methacrylate (GelMA)-based hydrogel microspheres (PGMS) could be controllable through adjusting the freezing time of hydrogel microspheres, the range of particles and pores size are 150-250 μm and 10-100 μm with different freezing time from 0 min to 30 min. The optimized particle size (200.8 ± 14.2 μm) and pore size (11.2 ± 1.9 μm) were explored to promote cell assemble, adhesion, growth, and proliferation in the PGMS. Furthermore, the co-assembly and delivery of bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) on the PGMS was achieved and an optimal cellular ratio of BMSCs to HUVECs (20:2) was established for co-culturing of them to achieve optimal paracrine effects, further promoting osteogenic differentiation and angiogenesis. Finally, results from both in vitro and in vivo experiments showed that the developed PGMS with co-assembly of BMSCs to HUVECs contributed to accelerate bone regeneration and vascularization process daringly, exhibited great potential in vascularized bone tissue reconstruction.
骨缺损治疗的关键挑战之一是在新组织再生过程中提供充足且稳定的血液供应。间充质干细胞（MSCs）和内皮细胞（ECs）通过旁分泌效应在骨缺损修复过程中具有促进成骨和血管生成的巨大潜力，但其治疗效果取决于有效的细胞组装和递送。在这项工作中，我们通过结合微流控和梯度冷冻干燥技术，开发了具有不同孔径的各种微球用于多细胞递送，以增强血管生成和成骨能力。通过调节水凝胶微球的冷冻时间，可控制制备的基于甲基丙烯酸明胶（GelMA）的多孔水凝胶微球（PGMS）的颗粒和孔径大小，在0分钟至30分钟不同冷冻时间下，颗粒和孔径大小范围分别为150 - 250μm和10 - 100μm。探索了优化的粒径（200.8±14.2μm）和孔径（11.2±1.9μm）以促进细胞在PGMS中的组装、黏附、生长和增殖。此外，实现了骨髓间充质干细胞（BMSCs）和人脐静脉内皮细胞（HUVECs）在PGMS上的共组装和递送，并确定了BMSCs与HUVECs的最佳细胞比例（20:2）用于它们的共培养以实现最佳旁分泌效应，进一步促进成骨分化和血管生成。最后，体外和体内实验结果均表明，所开发的具有BMSCs与HUVECs共组装的PGMS极大地促进了骨再生和血管化过程，在血管化骨组织重建中展现出巨大潜力。
