Orwin Elizabeth J, Borene Melinda L, Hubel Allison
Department of Engineering, Harvey Mudd College, Claremont, CA, USA.
J Biomech Eng. 2003 Aug;125(4):439-44. doi: 10.1115/1.1589773.
Cell matrix interactions are important in understanding the healing characteristics of the cornea after refractive surgery or transplantation. The purpose of this study was to characterize in more detail the evolution of biomechanical and optical properties of a stromal equivalent (stromal fibroblasts cultured in a collagen matrix). Human corneal stromal fibroblasts were cultured in a collagen matrix. Compaction and modulus were determined for the stromal equivalent as a function of time in culture and matrix composition. The corneal stromal fibroblasts were stained for alpha-smooth muscle actin expression as an indicator of myofibroblast phenotype. The nominal modulus of the collagen matrix was 364 +/- 41 Pa initial and decreased initially with time in culture and then slowly increased to 177 +/- 75 Pa after 21 days. The addition of chondroitin sulfate decreased the contraction of the matrix and enhanced its transparency. Cell phenotype studies showed dynamic changes in the expression of alpha-smooth muscle actin with time in culture. These results indicate that the contractile behavior of corneal stromal cells can be influenced by both matrix composition and time in culture. Changes in contractile phenotype after completion of the contraction process also indicate that significant cellular changes persist beyond the initial matrix-remodeling phase.
细胞与基质的相互作用对于理解屈光手术或移植后角膜的愈合特性至关重要。本研究的目的是更详细地描述基质等效物（在胶原基质中培养的基质成纤维细胞）生物力学和光学特性的演变。将人角膜基质成纤维细胞培养在胶原基质中。测定基质等效物的压实度和模量随培养时间和基质组成的变化。对角膜基质成纤维细胞进行α-平滑肌肌动蛋白表达染色，作为肌成纤维细胞表型的指标。胶原基质的标称模量初始为364±41 Pa，在培养过程中最初随时间下降，然后在21天后缓慢增加至177±75 Pa。添加硫酸软骨素可减少基质的收缩并增强其透明度。细胞表型研究显示，α-平滑肌肌动蛋白的表达随培养时间动态变化。这些结果表明，角膜基质细胞的收缩行为可受基质组成和培养时间的影响。收缩过程完成后收缩表型的变化也表明，在初始基质重塑阶段之后，显著的细胞变化仍然存在。
