The mechanical properties of amniotic membrane influence its effect as a biomaterial for ocular surface repair
The mechanical properties of amniotic membrane influence its effect as a biomaterial for ocular surface repair
复制标题
DOI：
10.1039/c2sm26175h
复制
发表时间：
2012-01-01
期刊：
影响因子：
3.4
通讯作者：
Connon, Che J.
中科院分区：
文献类型：
--
作者：
Chen, Bo;Jones, Roanne R.;Connon, Che J.
人羊膜 (AM) 是一种胎儿来源的组织，已被证明在临床上可用作治疗各种眼表疾病（包括角膜干细胞移植）的生物材料。然而，其成功率显示出一定程度的临床不可预测性。我们认为，测量到的 AM 硬度变异性可以解释当其用作干细胞扩增和移植的基质时临床再现性差的原因。角膜上皮干细胞在具有不同机械刚度的 AM 样品上扩增。为了进一步研究生物基质硬度对细胞表型的重要性，我们用已知硬度的 I 型胶原凝胶代替 AM。使用剪切流变仪测量基材刚度，并使用扫描电子显微镜和原子力显微镜表征表面形貌。使用RT-PCR、免疫组织化学和Western blotting检测上皮细胞的分化状态。在具有高动态弹性剪切模量的AM上扩增的细胞中角膜干细胞分化水平增加，并且在I型胶原凝胶上的细胞扩增证实角膜上皮干细胞分化水平与基底的机械性能相关。在本文中，我们提供证据表明临床使用的 AM 制备方法会影响其机械性能，并且这些测量到的差异会影响扩增的角膜上皮干细胞内的分化水平。
The human amniotic membrane (AM) is a tissue of fetal origin and has proven to be clinically useful as a biomaterial in the management of various ocular surface disorders including corneal stem cell transplantation. However, its success rate displays a degree of clinical unpredictability. We suggest that the measured variability inAMstiffness offers an explanation for the poor clinical reproducibility when it is used as a substrate for stem cell expansion and transplantation. Corneal epithelial stem cells were expanded upon AM samples possessing different mechanical stiffness. To investigate further the importance of biological substrate stiffness on cell phenotype we replaced AM with type I collagen gels of known stiffness. Substrate stiffness was measured using shear rheometry and surface topography was characterized using scanning electron microscopy and atomic force microscopy. The differentiation status of epithelial cells was examined using RT-PCR, immunohistochemistry and Western blotting. The level of corneal stem cell differentiation was increased in cells expanded upon AM with a high dynamic elastic shear modulus and cell expansion on type I collagen gels confirmed that the level of corneal epithelial stem cell differentiation was related to the substrate's mechanical properties. In this paper we provide evidence to show that the preparatory method of AM for clinical use can affect its mechanical properties and that these measured differences can influence the level of differentiation within expanded corneal epithelial stem cells.