Resurfacing potential of heterologous chondrocytes suspended in fibrin glue in large full-thickness defects of femoral articular cartilage: an experimental study in the goat

A large full-thickness articular-cartilage defect was created in the medial femoral condyle of 32 adult goats. The defects were xenografted with isola ted rabbit chondrocytes suspended in fibrin glue. Sham operated goats, wher e only a standardized defect was created, were used as controls. Results of cartilage repair were assessed after 3, 8, 13, 26 and 52 weeks. The repair tissue was evaluated macroscopically, histologically and biochemically. Re sults indicated that xenografted rabbit chondrocytes survived the transplan tation and maintained their potential to produce matrix in fibrin glue, par ticularly if they were located in a non-weight-bearing area. In terms of an immunological reaction to xenografted chondrocytes, only mild signs of syn ovitis were observed in both groups and rejection of transplanted cells did not occur. From 3 weeks gradually progressive resolvement of the fibrin gl ue was observed with subsequent replacement by fibrous tissue. Initially xe nografted defects histologically showed better tendency for cartilage regen eration, however, 52 weeks after surgery no significant differences could b e detected in the repair tissue of both groups macroscopically, histologica lly and on biochemical scoring. The amount of collagen type II in the newly synthesized matrix was 75% 1 year after surgery. This study shows that iso lated heterologous chondrocytes can be used for transplantation in articula r cartilage defects, however, fibrin glue does not offer enough biomechanic al support to the cells to maintain its function as a three-dimensional sca ffold. (C) 1999 Elsevier Science Ltd. All rights reserved.