可注射温固化支架复合异体软骨细胞修复关节软骨缺损的初步研究

目的探讨可注射性温固化凝胶壳聚糖-甘油磷酸钠（C-GP）复合同种异体软骨细胞在体内形成透明软骨和注入关节腔后修复关节软骨缺损的可行性和有效性。方法将预制的壳聚糖和甘油磷酸钠按一定体积比制成混合液，实验组为支架复合同种异体软骨细胞，设单纯支架和生理盐水为两组对照。注入成年兔的背部皮下和预制关节软骨缺损的关节腔内，复合物在体内37℃形成凝胶，术后4、8、12周分别行大体、组织学（HE、TB）、Ⅱ型胶原免疫组织化学观察，并进行Wakitani评分。观察其体内成软骨和填充并修复关节缺损效果。结果液态C-GP复合物注入体内可形成凝胶，实验组皮下生长4周，组织学观察示典型的透明软骨样结构且分泌基质；C-GP复合细胞注入关节腔可很好地填充关节缺损，并于4周后开始形成透明软骨样结构且表面平整与宿主整合良好，组织学切片上可见类软骨形成并分泌甲苯胺蓝异染的软骨基质和软骨特异性Ⅱ型胶原。结论可注射性C-GP复合软骨细胞体内可形成具有一定形态功能的类软骨组织，能够应用于微创技术再生修复软骨的缺损。

Repairing of articular cartilage defect by the allograft chondrocytes embedding in an injectable thermosetting gel

Objective To investigate the feasibility and the effectiveness of allograft chondrocytes mixed in the injectable thermosetting chitosan and glycerophosphate(C-GP) gel forming hyaline cartilage in vivo and repairing the whole layer defects of femur trochlea of rabbit keen joint.Methods The gel is base on chitosan and glycerophosphate mixed in certain volume ratio.The chondrocytes encapsulated in C-GP gel were injected into dorsa-subcutaneous and joint cave of rabbit forming monolithic gels at body temperature.The specimens were excised at the 4th,8th,12th week,examined grossly and analyzed by haematoxylin eosine,toluidine blues staining and type II collagen immunohistochemistry reaction.Wakitani score was counted to evaluate the repairing effect.Results In vivo the injectable liquid formulations turned into gel implant in site.Chondrocytes in chitosan and glycerophosphate mixture gels retained their surrounded morphology,multiplied,and produced matrix.Complex injected into articular cavity after 4 weeks obvious new cartilage-like tissues was found with smooth surface,and well-integrated the tissues around it.The results of histological and histochemistry examination were strong positive.Conclusion Injectable complexes of chondrocytes encapsulated in C-GP gel can form cartilage-like tissue with some shape and function and repair articular defect well in the 12 weeks.Combinant of chondrocytes and C-GP mixture gel may be one of the ideal injectable tissue-engineering cartilage.