Vrana E, Builles N, Hindie M, Damour O, Aydinli A, Hasirci V
BIOMAT, Department of Biological Sciences, Biotechnology Research Unit, Middle East Technical University, Ankara 06531, Turkey.
J Biomed Mater Res A. 2008 Feb;84(2):454-63. doi: 10.1002/jbm.a.31442.
Corneal stroma is a very complex structure, composed of 200 lamellae of oriented collagen fibers. This highly complex nature of cornea is known to be important for its transparency and mechanical integrity. Thus, an artificial cornea design has to take into account this complex structure. In this study, behavior of human corneal keratocytes on collagen films patterned with parallel channels was investigated. Keratocytes proliferated well on films and reached confluency after 7 days in the incubation medium. Nearly all of the cells responded to the patterns and were aligned in contrast to the cells on unpatterned surfaces. Collagen type I and keratan sulfate secreted by keratocytes on patterned films appeared to be aligned in the direction of the patterns. The films showed an intermediate degradation over the course of a month. On the whole, transparency of the films increased with degradation and decreased by the presence of the cells. The decrease was, however, low and transparency level was maintained on the patterned films while on the unpatterned films a sharp decrease in transparency was followed by an improvement. This was due to the more organized distribution of cells and the oriented secretion of extracellular matrix molecules on patterned collagen films. Thus, these results suggest that application of contact guidance in cornea tissue engineering may facilitate the remodeling process, hence decrease the rehabilitation period.
角膜基质是一种非常复杂的结构，由200层定向排列的胶原纤维组成。已知角膜这种高度复杂的性质对其透明度和机械完整性很重要。因此，人工角膜的设计必须考虑到这种复杂结构。在本研究中，研究了人角膜基质细胞在具有平行通道图案的胶原膜上的行为。角膜基质细胞在膜上增殖良好，在培养介质中培养7天后达到汇合状态。与未图案化表面上的细胞相比，几乎所有细胞都对图案有反应并排列整齐。图案化膜上的角膜基质细胞分泌的I型胶原和硫酸角质素似乎沿图案方向排列。在一个月的时间里，这些膜呈现出中等程度的降解。总体而言，膜的透明度随着降解而增加，并且由于细胞的存在而降低。然而，这种降低程度较低，图案化膜上的透明度水平得以维持，而未图案化膜上透明度先是急剧下降，随后有所改善。这是由于图案化胶原膜上细胞分布更有序以及细胞外基质分子的定向分泌。因此，这些结果表明在角膜组织工程中应用接触导向可能会促进重塑过程，从而缩短康复期。
