A Study on the Optimal Culture Condition and Biomechanical Properties of In Vitro Tissue Engineered Cartilage Using a Fibrin Glue Scaffold

ABSTRACT

The purpose of this study was to examine the feasibility of using fibrin glue polymer designed to produce tissue-engineered cartilage by in vitro culture and to determine the optimal fibrinogen and chondrocyte concentrations required to generate cartilage and to evaluate the biomechanical properties of the generated cartilages. The most favorable fibrinogen and chondrocyte concentrations were determined by measuring the volume and weight gains, evaluating the histologic changes and measuring the biomechanical properties after construction of 12 different chondrocyte-fibrin glue constructs. The results are as follows. 1. The fibrin glues without chondrocytes degraded during 8 weeks of culture period. 2. The construct gains more weight in those with higher chondrocyte and fibrinogen concentration. 3. Histologic analysis of the generated cartilage showed nearly homogeneous cartilage when using 80 mg/cc fibrinogen and 4 x 10(7) chondrocyte/cc at 8 weeks in vitro culture. 4. The compressive modulus is higher in constructs with higher fibrinogen concentration and is 35.4 -36.8% of the normal joint cartilage. 5. The yield stress is higher in constructs with higher fibrinogen concentration and is 11% of the normal joint cartilage. This study demonstrates that fibrin glue is a suitable polymer for generation of cartilage by in vitro culture method. The construct with 80 mg/cc fibrinogen and 4 x 10(7) chondrocyte/cc yields the best quality of cartilage at 8 weeks when analyzed by weight and volume changes, histology and biomechanical properties. The compressive modulus and yield stress of the generated cartilage are lower than those of normal joint cartilage, and may still be adequate for the purpose of craniofacial reconstruction which seeks more pliant cartilage not requiring weight bearing strength.