ABSTRACT
BACKGROUND:Non-hematopoietic cell of mesenchymal stem cells (MSCs) or mesenchymal progenitor cells can differentiate into bone,cartilage,muscle,tendon,fat and bone marrow matrix in vivo and in vitro,thus becoming very valuable seed cells source in the field of tissue engineering.OBJECTIVE:To construct the tissue engineered tendon withⅠcollagen-polyglycolic acid as a scaffold and bone marrow MSCs as seed cells,and to observe the effect of tissue engineered tendon on repairing achilles tendon defects. DESIGN,TIME AND SETTING:Randomized controlled animal experiment was performed in the Xiangya Medical College of Central South University in 2003.MATERIALS:Healthy adult rabbits,irrespective of genders,weighing 1.5-2.5 kg,were offered by Animal Center of Xiangya Medical College,Central South University. Polyglycolic acid were purchased from Shandong Weigao Group Kanglida Medical Products Co.,Ltd (KLD Medical).SD rats were sourced from Department of Experimental Animals,Central South University.METHODS:Rabbit bone marrow was extracted to harvest MSCs with centrrfugation and adherence method,then bone marrow MSCs were isolated and amplified. Tail tendon was extracted from SD rats and prepared into type Ⅰ collagen solution,which was mixed and suture cultured with polyglycolic acid to construct collagen-polyglycolic acid scaffold. Other bone marrow MSCs,which were not induced in vitro,were incubated on collagen-polyglycolic acid scaffold to construct tissue engineered rabbit tendon models,with those without cells serving as controls. Thirty rabbit angle skins were cut open to separate tendon and produce a 3-cm defect. Fifteen rats in the experiment group was repaired with tissue engineered tendon,which was previously prepared with autologous bone marrow MSCs,while fifteen rats in the control group was given Ⅰ collagen-polyglycolic acid scaffold.MAIN OUTCOME MEASURES:Effect of tissue engineered tendon on repairing achilles tendon defects in rabbit.RESULTS:No matter whether contains autologous bone marrow MSCs,type I collagen-polyglycolic acid scaffold transplanted into animals exhibited column gel shape by general observation. At 4 weeks following transplantation,cordlike tissues were seen in the transplantation site,polyglycolic acid suture was degraded. At 8 weeks,the tissue engineered tendon tissues were cordlike shaped,white,lustrous and dense. They were well connected with receptor tendon tissues in the experiment group,without adhesion to peripheral tissues. In the control group,the tissues were slender and adhered to peripheral tissues. CONCLUSION:Using typeⅠ collagen-polyglycolic acid as a scaffold and bone marrow MSCs as seed cells,tissue engineered tendon can dramatically promote the repair of achilles tendon defects.
ABSTRACT
0 05). A negative correlation was found between p16 expressions and the histological grade, clinical TNM stage, lymph-node metastasis and 5-years survival rate(P0 05), but associated with histological grade and lymph-node metastasis(P