The positive impact of platelet-derived growth factor on the repair of full-thickness defects of articular cartilage.

Abstract

This study aims to investigate the potential use and histological effects of the local administration of platelet-derived growth factor (PDGF) in the repair of full-thickness osteochondral defects in articular cartilage in an animal model. Twenty-four adolescent 18-week-old New Zealand White rabbits with an average weight of 2500 g (range, 1600 g to 3200 g) were used in the study. The rabbits were randomly divided into three groups (n=8) as the control group (group A) and two experimental groups (groups B and C). Defects of cylindrical full-thickness (3.5 mm wide, 4 mm deep) were created in the weight-bearing area of the right knee medial femoral condyles. In group A, the defect was left empty. In group B, the defect was filled with a collagen sponge. In group C, the defect was filled with a collagen sponge impregnated with PDGF. All rabbits were followed-up for 12 weeks. Right knee medial femoral condyles were used for macroscopic and histological analyses. At macroscopic level, the repair tissue was similar to normal adjacent cartilage at 12 weeks in group C. The surface of the repair tissue in group C was smoother and more regular compared to groups A and B. The total histological score of defects in group C was statistically significantly superior compared to groups A and B (p<0.05). Matrix staining and immunostaining of collagen type 2 were stronger in group C compared to the other groups, indicating the presence of a tissue similar to a normal cartilage. Platelet-derived growth factor can induce repair in full-thickness defects of articular cartilage in an animal model. Thus, this study demonstrates the potential use of PDGF for full-thickness osteochondral defects.