组织工程化软骨材料的特征

Characteristics of tissue engineered cartilage materials

支架可为诱导和加速新生软骨组织的生成提供理想的三维环境,理想软骨组织工程支架应该具备以下条件:①直接的、可控制的生物降解。②促进细胞的活化、分化和细胞外基质的产生。③黏附性,能与周围的自体软骨组织融为一体。④能恰如其分地填补软骨缺损。⑤根据软骨的缺损部位提供必要的机械强度。⑥无毒的、非免疫源的且不能引起炎症反应。⑦可输送营养和代谢产物。目前,大量天然和合成的高聚物材料已被用于软骨修复支架的研究,这些高聚物材料按形态结构可分为:水凝胶、海绵及纤维网丝等。具有生物活性的天然高聚物支架包括:藻(朊)酸盐,琼脂糖,纤维蛋白,透明质酸,胶原,凝胶明胶,壳聚糖,硫酸软骨素和纤维素等。用于软骨修复的合成高聚物包括:聚α-羟基酯、聚乙二醇、聚NiPAAm、聚丙烯-反丁烯二酸、聚丙烯反丁烯二酸、聚氨酯聚氨基甲酸酯等。

Scaffolds provide a three-dimensional environment that is desirable for inducing and promoting the production of cartilaginous tissue. Ideally the scaffold should： （1） have directed and controlled degradation; （2） promote cell viability, differentiation, and extracellular matrix production; （3） adhere and integrate with the surrounding native cartilage; （4） span and assume the size of the defect; （5） provide mechanical integrity depending on the defect location; （6） have no toxicity, no immunogenicity or inflammatory induction; （7） allow for the diffusion of nutrients and waste products. To date, a wide range of natural and synthetic materials have been investigated as a scaffold for cartilage repair. Based on the morphology and structure, these materials can be divided into hydrogel, sponge, fiber mesh and so on. Natural polymers that have been explored as bioactive scaffolds for cartilage engineering include： alginate, agarose, fibrin, hyaluronic acid, collagen, gelatin, chitosan, chondroitin sulfate, and cellulose. Synthetic polymers currently explored for cartilage repair include poly（α-hydroxy esters）, polyethylene glycol, poly（NiPAAm）, poly（propylene fumarates）, and polyurethanes.