Institute of Biochemical and Biomedical Engineering, Chang Gung University, Taoyuan, Taiwan 33302, Republic of China.
Biomacromolecules. 2010 May 10;11(5):1387-97. doi: 10.1021/bm100213f.
An efficient carrier for corneal endothelial cell therapy should deliver and retain the cell sheet transplants at the site of injury without causing adverse effects. Here we introduced a simple stirring process combined with freeze-drying (SFD1) method for the development of gelatin hydrogels with enlarged pore structure that can improve the aqueous humor circulation. Samples fabricated by air-drying (AD) or freeze-drying method were used for comparison. After cross-linking with 1 mM 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC), the discs were investigated to assess their functionality. The simultaneous presence of ice crystals and gas bubbles resulted in large pore size (461 +/- 85 mum) and high porosity (48.0 +/- 1.9%) of SFD1 carriers. Among all of the samples studied, the SFD1 hydrogels showed the most appropriate swelling characteristics without squeezing effect on the anterior segment tissues of the eye. The enlarged pore structure also allowed carriers to contain the highest fraction of mobile water and exhibit the lowest resistance to the glucose permeation. In comparison with AD samples, the SFD1 materials had better cytocompatibility and biocompatibility and more effectively prevented a drastic change of intraocular pressure. Rheological measurements showed that the SFD1 hydrogels behaved like an elastic solid and had a tough (rigid and deformable) texture. As a temporary supporter, the biodegradable gelatin hydrogel could facilitate cell sheet transfer and avoid long-term residence of foreign carriers in the body. Our findings suggest that the gelatin discs with enlarged pore structure have potential as cell sheet carriers for intraocular delivery and corneal tissue engineering.
一种有效的角膜内皮细胞治疗载体，应在损伤部位递送和保留细胞片移植，而不会引起不良反应。在这里，我们介绍了一种简单的搅拌工艺与冻干（SFD1）方法结合，开发出具有扩大的孔结构的明胶水凝胶，可改善房水循环。使用风干（AD）或冻干方法制备的样品进行比较。用 1mM1-乙基-3-（3-二甲基氨基丙基）碳二亚胺（EDC）交联后，评估了这些样品的功能。冰晶和气泡的同时存在导致 SFD1 载体具有大的孔径（461 ± 85 µm）和高孔隙率（48.0 ± 1.9%）。在所研究的所有样品中，SFD1 水凝胶表现出最适宜的溶胀特性，对眼球前段组织没有挤压作用。扩大的孔结构还允许载体包含最高比例的可移动水，并表现出最低的葡萄糖渗透阻力。与 AD 样品相比，SFD1 材料具有更好的细胞相容性和生物相容性，更有效地防止眼内压急剧变化。流变学测量表明，SFD1 水凝胶表现为弹性固体，具有坚韧（刚性和可变形）的质地。作为一种可生物降解的临时支撑物，明胶水凝胶可以促进细胞片的转移，并避免外来载体在体内的长期滞留。我们的研究结果表明，具有大孔结构的明胶片具有作为细胞片载体进行眼内给药和角膜组织工程的潜力。
