脂肪基质干细胞复合小肠黏膜下层治疗家兔生长板缺损

Treatment of growth plate defects in rabbits with adipose derived mesenchymal stem cells and small intestinal submucosa composites

背景:小肠黏膜下层具有良好的生物相容性,与其主要的胶原成分在进化上的高度保守性及其快速降解性有关。目的:观察经体外成软骨诱导的脂肪基质干细胞-小肠黏膜下层复合物用于治疗家兔胫骨近端内侧生长板缺损的疗效。方法:36只新西兰大耳白兔随机分为3组,均造成右侧胫骨近端内侧生长板50%的缺损。空白组不植入填充物,小肠黏膜下层支架组缺损填充空白小肠黏膜下层支架材料,脂肪基质干细胞-小肠黏膜下层组填充在体外进行成软骨诱导14d的脂肪基质干细胞-小肠黏膜下层复合物。结果与结论:X射线片测量结果:16周时胫骨近端关节面成角差值,空白组>小肠黏膜下层支架组>脂肪基质干细胞-小肠黏膜下层组(P均<0.05)。胫骨长度差值空白组>小肠黏膜下层支架组>脂肪基质干细胞-小肠黏膜下层组(P均<0.05)。苏木精-伊红染色显示:16周时,空白组生长板骨桥未被吸收,生长板外侧闭合,小肠黏膜下层支架组生长板缺损内骨桥致密,生长板软骨中断,生长板外侧闭合;脂肪基质干细胞-小肠黏膜下层组生长板为软骨性修复,软骨呈柱状排列,生长板未闭合。提示,体外成软骨诱导分化后的脂肪基质干细胞-小肠黏膜下层复合物,用于治疗家兔胫骨近端生长板缺损,有效避免了肢体的成角和短缩畸形,并且能够修复生长板软骨。

BACKGROUND：Small intestinal submucosa（SIS） has good biocompatibility,associated with high conservation and rapid degradation of its main component collage.OBJECTIVE：To observe reparative effect of adipose derived mesenchymal stem cells（ADSCs）-SIS composites induced by chondrogenic medium in vitro on growth plate defects in rabbits.METHODS：Thirty-six New Zealand rabbits of 6-8 weeks old were divided into 3 groups randomly,and 50% of medial growth plate in proximal right tibia was excised.The defects of growth plates in blank group were not filled,the defects of growth plates in control group were filled with SIS without cells,and the defects of growth plates in experimental group were filled with ADSCs-SIS composites induced by chondrogenic medium in vitro for 14 days.rabbits of each group were sacrificed at 4,8 and 16 weeks,leg bones of both sides were taken off,fixed with 10% formalin solution,X ray photographs were taken to measure tibial length and proximal tibial articular surface angle（PTAS angle）.Calculated the differences of PTAS angle and length of left and right tibias of each rabbit,and compared the differences.Paraffin slices stained with HE were used to observe reparative effect of ADSCs-SIS composites on growth plate cartilage.RESULTS AND CONCLUSION：Comparison of X ray photograph measurement among 3 groups showed that 16 weeks after operation,proximal tibial articular surface（PTAS） angle difference of the blank group was larger than that of the control group（P 0.05） and that of the experimental group（P 0.05）,and PTAS angle difference of the control group was larger than that of the experimental group（P 0.05）.Tibial length difference of the blank group was larger than that of the control group（P 0.05） and that of the experimental group（P 0.05）,and tibial length difference of the control group was larger than that of the experimental group（P 0.05）.Paraffin slices stained with hematoxylin-eosin showed that,16 weeks after operation,bone bridges could be seen in growth plates of the blank group and control group,and cartilages rearranged like column in the medial half of growth plates in the experimental group.ADSCs-SIS composites induced by chondrogenic medium in vitro could prevent angular deformity and length discrepancy of the tibia effectively after being implanted into medial growth plate defects of the proximal tibia,and could repair cartilage of growth plates.