Biomedical Research Group, School of Mechanical and Design Engineering, Technological University Dublin, Bolton St, Dublin 1, Ireland; Tissue Engineering Research Group, Dept. of Anatomy and Regenerative Medicine, RCSI University of Medicine and Health Sciences, 123 St. Stephen's Green, Dublin 2, Ireland.
Tissue Engineering Research Group, Dept. of Anatomy and Regenerative Medicine, RCSI University of Medicine and Health Sciences, 123 St. Stephen's Green, Dublin 2, Ireland; Advanced Materials and Bioengineering Research (AMBER) Centre, RCSI, Ireland.
Mater Sci Eng C Mater Biol Appl. 2021 Jan;120:111788. doi: 10.1016/j.msec.2020.111788. Epub 2020 Dec 10.
Elastic fibres play a key role in bodily functions where fatigue resistance and elastic recovery are necessary while regulating phenotype, proliferation and migration in cells. While in vivo elastic fibres are created at a late foetal stage, a major obstacle in the development of engineered tissue is that human vascular smooth muscle cells (hVSMCs), one of the principal elastogenic cells, are unable to spontaneously promote elastogenesis in vitro. Therefore, the overall aim of this study was to activate elastogenesis in vitro by hVSMCs seeded in fibrin, collagen, glycosaminoglycan (FCG) scaffolds, following the addition of recombinant human tropoelastin. This combination of scaffold, tropoelastin and cells induced the deposition of elastin and formation of lamellar maturing elastic fibres, similar to those found in skin, blood vessels and heart valves. Furthermore, higher numbers of maturing branched elastic fibres were synthesised when a higher cell density was used and by drop-loading tropoelastin onto cell-seeded FCG scaffolds prior to adding growth medium. The addition of tropoelastin showed no effect on cell proliferation or mechanical properties of the scaffold which remained dimensionally stable throughout. With these results, we have established a natural biomaterial scaffold that can undergo controlled elastogenesis on demand, suitable for tissue engineering applications.
弹性纤维在身体功能中起着关键作用，在需要抵抗疲劳和弹性恢复的同时，调节细胞的表型、增殖和迁移。虽然体内的弹性纤维是在胎儿晚期形成的，但工程组织发展的一个主要障碍是，人类血管平滑肌细胞（hVSMCs）作为主要的弹性生成细胞之一，无法在体外自发地促进弹性生成。因此，本研究的总体目标是通过在纤维蛋白、胶原蛋白、糖胺聚糖（FCG）支架中接种 hVSMCs，在添加重组人原弹性蛋白后，在体外激活弹性生成。这种支架、原弹性蛋白和细胞的组合诱导了弹性蛋白的沉积和层状成熟弹性纤维的形成，类似于在皮肤、血管和心脏瓣膜中发现的弹性纤维。此外，当使用更高的细胞密度和在添加生长培养基之前将原弹性蛋白滴加载到细胞接种的 FCG 支架上时，合成了更多数量的成熟分支弹性纤维。添加原弹性蛋白对细胞增殖或支架的机械性能没有影响，支架在整个过程中保持尺寸稳定。有了这些结果，我们已经建立了一种天然生物材料支架，可以按需进行可控的弹性生成，适用于组织工程应用。
