Goldshmid Revital, Seliktar Dror
The Faculty of Biomedical Engineering and ‡The Interdisciplinary Program for Biotechnology, Technion-Israel Institute of Technology, Haifa 32000, Israel.
The Faculty of Biomedical Engineering and The Interdisciplinary Program for Biotechnology, Technion-Israel Institute of Technology, Haifa 32000, Israel.
ACS Biomater Sci Eng. 2017 Dec 11;3(12):3433-3446. doi: 10.1021/acsbiomaterials.7b00266. Epub 2017 Nov 17.
Hydrogels have been used extensively with various cell types in three-dimensional (3D) culture, including with human mesenchymal stem cells (hMSCs). Here, we report on the use of poly(ethylene glycol) (PEG)-conjugated fibrinogen hydrogels to grow bone marrow-derived hMSCs in 3D culture. The initial modulus of the PEG-fibrinogen (PF) hydrogels was varied to study the influence of the stiffness on the proliferation response of the cells growing within. Shear rheology was used to quantify the changes to the initial material properties; the shear storage modulus of the PF was controlled by changing the concentration of synthetic PEG cross-linker, while keeping the fibrinogen concentration constant. Cell culture was performed during a 14-day experiment to quantify the cell proliferation response in the different modulus materials tested. The hMSCs were recovered from the hydrogels by mild enzymatic dissolution, and characterized for proliferation and cell number using cytometry. The results indicate a modulus-dependent response from the cells, and the ability to preferentially define initial hydrogel modulus that favors higher proliferation and multipotency of the hMSCs. Bioactive supplements added to the hydrogels, including exogenous fibronectin (Fn) and von willebrand factor (vWf) were used to further stimulate the proliferation response of the hMSCs in the hydrogel cultures, without altering their multipotency. These insights underscore the importance of mechanical properties in regulating cell proliferation in a 3D culture milieu. The versatility of the hydrogel culture environment and the ability to control mechanical properties for cell-fate determination further highlight the significance of a modular approach when developing materials that ultimately optimize stem cell cultures.
水凝胶已广泛应用于三维（3D）培养中的各种细胞类型，包括人骨髓间充质干细胞（hMSCs）。在此，我们报告了使用聚乙二醇（PEG）共轭纤维蛋白原水凝胶在3D培养中培养骨髓来源的hMSCs。改变PEG-纤维蛋白原（PF）水凝胶的初始模量，以研究硬度对其中生长的细胞增殖反应的影响。使用剪切流变学来量化初始材料特性的变化；通过改变合成PEG交联剂的浓度来控制PF的剪切储能模量，同时保持纤维蛋白原浓度恒定。在为期14天的实验中进行细胞培养，以量化在不同模量材料中测试的细胞增殖反应。通过温和的酶解从水凝胶中回收hMSCs，并使用细胞计数法对增殖和细胞数量进行表征。结果表明细胞有模量依赖性反应，并且能够优先确定有利于hMSCs更高增殖和多能性的初始水凝胶模量。添加到水凝胶中的生物活性补充剂，包括外源性纤连蛋白（Fn）和血管性血友病因子（vWf），用于进一步刺激水凝胶培养中hMSCs的增殖反应，而不改变其多能性。这些见解强调了机械性能在调节3D培养环境中细胞增殖方面的重要性。水凝胶培养环境的多功能性以及控制机械性能以确定细胞命运的能力，进一步突出了开发最终优化干细胞培养的材料时采用模块化方法的重要性。
