EFFECT OF BASIC FIBROBLAST GROWTH-FACTOR ON CARTILAGE REGENERATION INCHONDROCYTE-SEEDED COLLAGEN SPONGE SCAFFOLD

A chondrocyte-collagen composite was prepared in an attempt to regener ate cartilage by its subcutaneous implantation in nude mouse. When the composite was impregnated with basic fibroblast growth factor (bFGF) prior to implantation, regeneration of the cartilage tissue was remark ably accelerated. Histological staining of the implanted composites wi th Safranin O-fast green revealed that the cells incorporated in the c omposites exhibited their phenotype and formed a new matured cartilage . A thin layer of fibrous capsule was observed surrounding the implant ed composite and the inflammatory response of the host to the implant was mild. Specific proteoglycans were accumulated in the composite eve n 1 week after implantation. At 2 weeks after implantation, the chondr ocytes regenerated the cartilage tissue, although still immature, but at 4 weeks almost all of the chondrocytes transferred to the mature st age. Conversely, such mature cartilage tissue was not noticed up to 4 weeks after implantation if the collagen scaffold was not impregnated with bFGF. Moreover, the mature area was limited to only a small fract ion of the implanted composite, unless bFGF was incorporated in it.