壳多糖组织工程支架材料的制备及其应用

目的:探索一种简单的制备壳多糖细胞外基质网架的方法，考察该基质网架作为组织工程支架材料应用的可行性。方法:壳多糖溶于乙酸，搅拌成均匀泡沫状，冷冻铸型制成海绵状多孔基质网架。利用光镜、电镜等方法测定该网架的孔径和空孔率。分别应用该网架构建复层组织工程皮肤和组织工程软骨。 结果：制备的壳多糖网架外观呈多孔海绵状，光镜下观察有大小不等的孔隙；扫描电镜下观察，网架错综相连成许多网孔，孔径为83～136 μm，平均孔径为110 μm，平均三维空孔率为78%。构建的复层组织工程皮肤具有与天然皮肤极为相似的表皮和真皮双层结构，皮肤角朊细胞和成纤维细胞贴附于网架生长、增殖，形成连续的细胞层，细胞层数增多明显，并分泌角质样物质和基质样物质，网架逐渐降解。软骨细胞在网架上贴附、增殖良好，并分泌细胞外基质；组织学观察有新生软骨组织形成。结论：制备的壳多糖细胞外基质网架具有一定的孔径和空孔率，适于细胞贴附生长和增殖，将其作为组织工程支架材料具有较好的应用前景。

Preparation and application of chitosan tissue engineering scaffold

Objective To explore one simple way of preparation of chitosan extracellular matrix wire frame,and investigate its application as scaffold for tissue engineering.Methods Chitosan and acetic acid were soluted and stirred into uniform foam,and made into porous and spongiform wire frame after refrigeration and casting.The pore size and vacancy volume of the wire frame were determined under light microscope and SEM.Tissue engineered skin and cartilage were reconstructed with chitosan scaffold.Results Chitosan extracellular matrix wire frame looked porous and spongiform,its pores manifested inequality of size under light microscope,and many interlacing pores were found under SEM with pore size of 83-136 μm(average 110 μm).The three diamensions lattice had a vacancy volume of 78%.The tissue engineering skin was similar with natural skin and had bilayer structure.Keratinocytes and fibroblasts sticking on chitosan grew and proliferated,and formed into contiguous cellular layer.They increased obviously and secreted cutin and matrix.The wire frame degraded gradually.Chondrocytes sticking on wire frame grew and proliferated well,and they also secreted extracellular matrix.Generation of new cartilage tissue was found with histological observation.Conclusion The chitosan extracellular matrix wire frame has certain pore size and vacancy volume.And it is fit for cell growth and proliferation.There will be brilliant perspective for application as tissue engineering scaffold.