Determination Of Proteoglycan In Articular Cartilage Matrix In Homo-transplantation

Objective Cartilage is a highly differentiated tissue and therefore has a limited capacity for self-repair. The treatment of articular cartilage defects has been a problem in orthopedic surgery up to now .The defects may be caused by trauma or evolved during the course of diseases. The large defects at articular cartilage are often repaired by fibrocartilage rather than normal hyaline cartilage. The repairing fibrocartilage tissues are different from hyaline cartilage in either biochemically or biomechanically and it ultimately deteriorates. In spite of extensive research on stimulating repair of articular cartilage defects. No reliable methods to achieve this goal which has been described so far. The transplantation of cartilage tissue-engineering is an idea method to repair the articular cartilage defects, and a important method to restoration the cartilage than replacement. This method is not applied in clinic, Nowday ,the study has received more attention how to select the biodegradabile scaffolds which can provide 3-dimensional tissuelike enviroment for cell and evaluated the tissue with the macroscopic , histological electronmicroscopic, determention of collagen. However, the study has been paid little attention to anotherimportant component_<sub>proteoglycan. Our study is to determine theproteoglycan of the repaired tissue, to seek for the feasibility to repair the full_thickness articular cartilage defects with the method of PluronicF₁27 carried engineered chondrocytes homotransplantations. Material and Method Chondrocytes obtained from 4 wweks old New Zealand immature rabbits,which were cultured and mixed with 20%PluronicF₁27. A total of 27 healthy adult rabbits which were made defects of articular cartilage in their bilateral femoral condylar (downto the calcified ,3.5mm in diameter), were randomly divided into three groups: A test group, PluronicF₁27 was used as a vehicle of chondrocytes which were transplanted into the defects of articular cartilage. B PluronicF₁27 filled alone group. C void control group. At 4,8,12 weeks after the operation, we harvested the repair tissue, and evaluated the tissue with the macroscopic, determine the proteoglycan of the repaired tissue and the normal articular cartilage, draw the conclusion after statistical analysis.Results The chondrocyte in the composite of PluronicF₁27 can proliferate well. The new tissues which filled the entire area of the defects at 4 weeks postoperation were distinguished easily. The cartilage was filled in some superficial area. At 8 and 12 weeks after tansplantation, the gross appearance of the defects was similar to that of normal cartilage around the defects. At4, 8 and 12 weeks after tansplantation, there was a significant statistical difference between test group and other two groups, there was a significant statistical difference between different period of test group,and there was no statistical difference between test group and normal cartilage after 12 weeks.Conclusion The mixture of PluronicF₁27 and culture chondrocytes can repair successfully the cartilage defects of femoral condyle of rabbit knees in mode of hyaline cartilage. The proteoglycan of the repaired tissue is increased gradually and show no difference at 12 weeks after tansplantation. Homo-transplantation with PluronicF₁27 engineered chondrocytes is an idea method to repair the articular cartilage defects.