The Effect of Chitosan-TGF-beta1 Conjugate on Full Thickness Articular Cartilage Defect in the Rabbit Knee Model (Preliminary Report)

Abstract

PURPOSE To evaluate the effect of the chitosan-TGF-beta1 conjugate on articular cartilage defects of rabbits' knees MATERIALS AND METHODS Full thickness cartilage defect(6mm, round shape) was made at both knees of 20 rabbits and, after the lapse of 3 days, chitosan-TGF-beta1(15ng/ml, 1ml) was injected into one side(experimental group) of knees and PBS(1ml) was injected into the other side(control group). 5 rabbits were sacrificed 6 weeks after the injection and the rest of 15 rabbits 12 weeks later. Then, gross morphology and histological evaluation(Mendelson scoring) was conducted. RESULTS No arthritic findings was observed and histological results in the experimental group at 6(Ave. 11.3+/-1.5) and 12(Ave. 4.5+/-1.9) weeks postoperatively were superior to those in the control group at 6(Ave. 14.6+/-1.7) and 12(Ave. 9.8+/-2.2) weeks. Especially at 12 weeks, the experimental group was superior to the control group statistically in results of 5 subgroups except for filling of defects. The difference of two groups at 12 weeks was more remarkable than those at 6 weeks. CONCLUSION Regeneration of something very close to normal cartilage was observed in the experimental group. It shows that the biological activity of TGF-beta1 is sustained by the action of conjugate with chitosan, through prolonged half life of TGF-beta1.