ANALYSIS OF THE PROLIFERATIVE POTENTIAL O F HUMAN NASAL CHONDROCYTES FOR THE ENGINEERING OF CARTILAGE TRANSPLANTS

Background: Recent developments in the field of tissue engineering pro vide novel approaches in tissue repair and reconstructive surgery usin g the patients own cells. Isolated chondrocytes form new cartilage whe n seeded in appropriate scaffolds. Usually the number of cells from a cartilage biopsy is not sufficient. The present study investigates the potential of cell amplification of human nasal chondrocytes in monola yer culture. Methods: Nasal cartilage cells from seven healthy patient s with age between 16 and 60 years were enzymatically isolated with co llagenase and hyaluronidase. Subsequently, cells were seeded in 75 cm( 2) culture flasks. After confluency, cultures were trypsinized, counte d, and again seeded at a concentration of 5 x 10(4) cells/ml. Dulbecco 's MEM supplemented with 10% FCS was used as culture medium. Results: After enzymatic digest, an average of 5 x 10(5) cells per patient were isolated. At least 85% of the cells were vital. Within four to eight weeks, the cells number was increased 10(3) to 10(5) fold. No correlat ion between the proliferative activity and the age of the patient was observed in this study. Discussion: The observed increase in cell numb er resembles about 10 to 20 cell doublings. Although the doubling time appears to be longer during the second month, no definite limit of pr oliferative activity was seen during the time of study. Proliferating chondrocytes in monolayer lose their tissue-specific phenotype. For th e de novo formation of cartilage transplants, redifferentiation of the expanded cells has to be stimulated. Conclusion: This study shows tha t human nasal chondrocytes can be expanded sufficiently in monolayer f or the engineering of autologous cartilage transplants.