Collagen-chitosan hybrid scaffolds for tissue engineering

使用新组织支架递送和移植细胞以再生患病或缺失的结缔组织是改善组织工程和健康的有吸引力的方法。压缩超水合凝胶最近被报道为一种突破性的快速制造方法，用于精确地制造具有明确结构和增加强度的三维纤维状胶原支架，用于组织工程。有或没有细胞，这些代表了从以前的方法的主要转变，因为它们提供了基于结缔组织中发现的细胞外基质生物学的支架。反映生理组织结构的坚固的基于生物聚合物的材料可以在几分钟内（而不是几天或几周内）通过压缩制造，并且可以产生容易植入的新组织。通过认识到流体通常不是重构的高水合凝胶的结构的关键组分，压缩制造可以作为广泛适用的技术应用于其他高水合凝胶（>95%流体水凝胶）;因此，通过压缩去除流体可以大大改善可植入支架的性能。预计通过改变蛋白质与多糖的组成，将有可能控制生物活性和生物降解性以及机械和超微结构特性。通过将压缩技术应用于胶原-壳聚糖混合物，可以对新组织支架的基质-流体组成施加进一步的控制水平。这些混合支架的压缩还将以直接影响细胞行为的方式提供对新组织结构的控制，并允许其适应环境依赖性细胞的增强行为。

The use of neotissue scaffolds for the delivery and transplantation of cells to regenerate diseased or missing connective tissues is an attractive approach to improving tissue engineering and health. Compression of hyper-hydrated gels has recently been reported as a ground-breaking rapid fabrication method to accurately make three-dimensional, fibrillar collagen scaffolds having well-defined architectures and increased strength for tissue engineering. With or without cells, these represent a major shift from previous approaches in that they provide scaffolding based on the biology of extracellular matrices found in connective tissues. Strong, biopolymer-based materials reflecting physiologic tissue structure can be fabricated by compression within minutes (rather than in days or weeks) and can produce readily implantable neotissues. Compression fabrication can be applied to other hyper-hydrated gels (>95% fluid hydrogels) as a widely applicable technology by recognising that fluids are typically not a key component of the structure of reconstituted, hyper-hydrated gels; thus, its removal by compression can greatly improve the properties of implantable scaffolds.Collagen-chitosan mixtures are inherently biocompatible materials. It is anticipated that by varying the composition of protein to polysaccharide, it will be possible to control bioactivity and biodegradability as well as mechanical and ultra-structural properties. By applying the compression technique to the collagen-chitosan mixtures, a further level of control can be exerted over the matrix-to-fluid composition of the neotissue scaffolds. Compression of these hybrid scaffolds will also provide control over neotissue structure in a manner which will directly affect cell behaviour, and allow it adaptation for enhanced behaviour of environment-dependent cells.