凝胶包埋骨髓基质干细胞复合脱钙骨基质修复关节软骨缺损

Repair of articular cartilage by bone marrow stromal cell encapsulated in type Ⅱ collagen gel embedded into dematerialized bone matrix scaffolds

目的探索Ⅱ型胶原凝胶包埋的自体骨髓基质干细胞（BMSCs）接于同种异体脱钙骨基质（DBM）材料修复兔关节软骨缺损的效果。方法15只健康成年新西兰大白兔，雌雄不限，体质量约3．0kg，兔龄6。9个月；以Urist方法制作同种异体DBM材料。以Ⅱ型胶原蛋白配制水凝胶．以水凝胶包埋兔BMSCs并接种于同种异体DBM材料，构建组织工程复合物。在新西兰大白兔股骨髁关节面制造软骨缺损。分组进行修复。将健康成年新西兰大白兔27只（雌雄不限，体质量约2．5kg．兔龄3～4个月）共54侧膝关节随机分为Ⅱ型胶原／DBM／BMSCs修复组（实验组）、Ⅱ型胶原／DBM修复组（实验对照组）及空白对照组。于术后4周、8周及12周各处死9只动物，取材对修复组织进行大体及组织学观察，根据Wakitani法对修复组织进行评分．数据输入SPSS11．5软件进行统计学分析，比较各组的评分差异是否具有统计学意义。结果实验组Ⅱ型胶原／DBM／BMSCs植入后形成透明软骨样修复．表面光滑平坦，与周围软骨及软骨下骨结合良好；实验对照组Ⅱ型胶原／DBM植入后有部分软骨样修复：而空白对照组仅有少量纤维性修复。根据组织学评分标准，实验组组织学评分为（20．25±1．64）分，高于实验对照组[（7．46±1．29）分]及空白对照组[（6．00±2．09）分]。结论Ⅱ型胶原自体BMSCs复合同种异体DBM支架材料修复全层关节软骨缺损的效果良好，是一种修复软骨缺损的行之有效的方法。

Objective To investigate the potential of three -dimensional seeding of bone marrow stromal cells （BMSCs） encapsulated in type R collagen gel into dematerialized bone matrix （DBM） scaffolds to repair articular cartilage of rabbits. Methods DBM was prepared by Urist＇s method from fifteen healthy aduh rabbits（either sex） with age of 6 - 9 months and body weigh of about 3.0 kg. BMSCs were encapsulated in type Ⅱ collagen gel and then seeded into DBM in vitro to construct tissue engineered complexes. Twenty-seven healthy New Zealand rabbits（aged 3 - 4 months with body weight of about 2.5 kg, either sex） were divided into 3 groups randomly（n = 9）. The cartilage defects were repaired with type Ⅱ collagen gel/BMSCs/DBM complex in group A（experimental group）, typeⅡ collagen gel/DBM in group B （experimental control group）, and no repair in group C（blank control group）. Three rabbits were killed at the 4th, 8th and 12th weeks after operation in each group, and the reparative tissue samples were histologically evaluated and the repairing effect was assessed by Wakitani＇ s score system. SPSS 11.5 software was applied to precede the statistic analysis. Results In the experimental group, cartilage defects were repaired with hyaline cartilage to form a smooth surface, and the surrounding cartilage and subchondral bone connected well, while there was partial cartilage defects repaired in the experimental control group. In the blank control group, there was only little fibrous tissue filling the defects. According to the standard in Wakitani S score system, the score of the experimental group was （20.25 ± 1.64）, which was higher than that in the experimental control group （7.46 ± 1.29） and blank control group （6.00 ± 2.09）. Conclusion It is demonstrated that type Ⅱ collagen gel/BMSCs/DBM complex have good effects, and it could be an efficient alternative for articular cartilage defects repair.