obtained under sterile conditions.We removed the tibia
and carefully scraped off the soft tissue and periosteum.
Eye scissors were used to obtain either side of the distal
tibia; proximal and articular cartilages were cleaned by
washing them several times with phosphate buffer solution
(PBS) without calcium or magnesium. Then cut up isolated
cartilage. The tissues were chosen without vascular invasion
and calcification. Chicken chondrocytes were isolated by a
sequential 700 IU/mL pronase and 300 IU/mL collagenase
digestion, as described previously [14]. The suspension was
filtered through 74