Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
J Tissue Eng Regen Med. 2009 Dec;3(8):623-33. doi: 10.1002/term.204.
The high morbidity of tendon injuries and the poor outcomes observed following repair or replacement have stimulated interest in regenerative approaches to treatment and, in particular, the use of cell-based analogues as alternatives to autologous and allogeneic graft repair. Given the known regenerative properties of fetal tissues, the objective of this study was to assess the biological and mechanical properties of tissue-engineered three-dimensional (3D) composites seeded with fetal skin cells. Dermal fibroblasts were isolated from pregnant rats and their fetuses and characterized in monolayer culture and on 3D resorbable polyester scaffolds. To determine the differences between fetal and adult fibroblasts, DNA, total protein and types I and III collagen production were measured. In addition, morphology and mechanical properties of the 3D constructs were examined. In monolayer culture, fetal fibroblasts produced significantly more types I and III collagen and displayed serum-independent growth, while adult fibroblasts elaborated less collagen and exhibited reduced cell spreading and attachment under low-serum conditions. In 3D culture, fetal constructs appeared more developed based on gross examination, with significantly more total DNA, total protein and normalized type I collagen production compared to adult specimens. Finally, after 35 days, fetal fibroblast-seeded constructs possessed superior mechanical properties compared to adult samples. Taken together, these findings indicate that fetal dermal fibroblasts may be an effective source of cells for fabricating tissue equivalents to regenerate injured tendons.
肌腱损伤的高发病率和修复或置换后观察到的不良结果激发了人们对治疗的再生方法的兴趣，特别是使用基于细胞的类似物作为自体和同种异体移植物修复的替代物。鉴于胎儿组织的已知再生特性，本研究的目的是评估接种胎儿皮肤细胞的组织工程三维（3D）复合材料的生物学和机械性能。从怀孕的大鼠及其胎儿中分离出真皮成纤维细胞，并在单层培养和 3D 可吸收聚酯支架上进行了特征描述。为了确定胎儿和成纤维细胞之间的差异，测量了 DNA、总蛋白和 I 型和 III 型胶原的产生。此外，还检查了 3D 构建体的形态和机械性能。在单层培养中，胎儿成纤维细胞产生的 I 型和 III 型胶原明显更多，并表现出血清非依赖性生长，而成年成纤维细胞产生的胶原较少，在低血清条件下细胞扩散和附着减少。在 3D 培养中，基于肉眼检查，胎儿构建体看起来更发达，与成年标本相比，总 DNA、总蛋白和归一化 I 型胶原的产量明显更多。最后，在 35 天后，胎儿成纤维细胞接种构建体的机械性能优于成年样本。总之，这些发现表明胎儿真皮成纤维细胞可能是制造组织等效物以再生受损肌腱的有效细胞来源。
