体内外环境对组织工程软骨组织结构与力学性能的影响  

Influence of in vivo or vitro microenvironment on the mechanical properties and histological structure of tissue engineered cartilage

作　　者：晏丹[1] 周广东[2] 曹谊林[2] 刘伟 张文杰[2] 

机构地区：[1]湖南省郴州市第一人民医院整形美容科,423000 [2]上海交通大学医学院组织工程研究重点实验室

出　　处：《中华整形外科杂志》2011年第5期367-372,共6页Chinese Journal of Plastic Surgery

基　　金：国家高技术研究发展计划（“863”计划）（2006AA02A126）;国家自然科学基金（30300353）

摘　　要：目的 探讨体外构建组织工程化软骨在体、内外环境中力学性能及组织结构的变化，以及微环境对组织形成的影响，为工程化软骨构建提供适当参数。方法体外培养扩增人胎儿关节软骨细胞，取第2代细胞以6×10^7个细胞／ml密度接种到聚羟基乙酸／聚乳酸（Polyglycolicacid／Polylacticacid，PGA／PLA）材料制成的圆柱形三维支架上，常规体外培养4周后，分为体内组（C、D组）和体外组（A、B组），C、D组植于裸鼠皮下，A、B组继续常规培养液培养，于6、12周后取材，以正常软骨作为对照，行大体观察，以及组织学、组织化学、生物力学、超微结构等检测。结果A、B、C、D4组均形成大体形态良好的透明软骨样组织。C、D组软骨呈乳白色，表面光滑，超微结构上胶原纤维排列致密而有规则，可形成有横纹的粗大胶原纤维，类似正常成人软骨；A、B组颜色偏黄，表面略粗糙，外观及超微结构近似半透明的胎儿关节软骨。工程化软骨植入体内12周后压缩弹性模量及胶原直径分别为（38．28±3．95）MPa和（41．58±2．78）nm，明显优于体外同时期组的（4．12±0．63）MPa和（15．83±1．70）nm（P〈0．01）。结论组织工程软骨的结构和功能在体内环境逐步成熟，体内组软骨超微结构上能形成粗大胶原纤维网络，胶原的交联增强可能是其力学性能较体外组明显提高的重要原因。ObjectiveTo investigate the influence of in vivo or vitro microenvironment on the mechanical properties and histological structure of tissue engineered cartilage, and to provide the appropriate parameters for cartilage construct in vitro. Methods Human fetal articular chondrocytes were cultured and expanded in vitro, the passage 2 chondrocytes were seeded at the density of 6 × 107 cells/cm3 to cylindric dimensional scaffolds made by polyglycolic acid (PGA) and polylactic acid (PLA). These constructs were cultured in vitro for 4 weeks. After 4 weeks, part of samples were implanted subcutaneously into nude mice for 6 and 12 weeks, the others continued to be cultured in vitro. All specimens were harvested after 6 and 12 weeks, and evaluated by gross observation, histology, histochemistry,ultrastructure and mechanical test. Results All specimens in vivo and vitro eventually formed good shape hyaline cartilage. The constructs in vivo group was white color with smooth surface, and had better mechanical properties than those in vitro, by TEM we can observe the thick and stiated collagen fibers in regularly arranged collagen fibril which was similar to adult articular cartilage. The constructs in vitro group was yellow color with coarse surface, the appearance and ultrastructure was similar to fetal articular cartilage. Specimens implanted for 12 weeks in vivo had better compressive modulus(38.28 ± 3.95 ) MPa and collagen diameter (41.58 ± 2. 78 ) nm than those cultured in vitro at the same time (4. 12 ± 0. 63 )MPa, ( 15.83 ± 1.70) nm( P ＜ 0. 01 ). Conclusions The structure and funtion of human tissue engineered cartilage became mature gradually from vitro to vivo, thick and stiated collagen fibrils net similar to adult articular cartilage can be formed in constructs of vivo group, increased collagen cross-linking might be the reason that their mechanical properties been greatly improved.

关 键 词：软骨 组织工程 生物力学 

分 类 号：R318.08[医药卫生—生物医学工程]