Background
Joint replacement surgery provides articular cartilage samples for chondrocyte isolation. To our knowledge, the effect of the collagenase type on releasing of chondrocytes from the extracellular matrix of cartilage is not reported. Objectives: To determine whether cartilage digested with collagenase IA yielded more chondrocytes than that digested with collagenase II and determine whether chondrocytes isolated with collagenase IA could be cultured in vitro.
Conclusion
Sequential digestion of human articular cartilage with pronase E and collagenase IA was more effective than collagenase II alone or collagenase II combined with pronase E for releasing chondrocytes from extracellular matrix of cartilage. Chondrocytes isolated with this method could be maintained in monolayer cultures for at least 2 passages with unaltered morphology.
Methods
Cartilage slices collected from 18 elderly patients who received joint replacement surgery (16 hips, 2 knees) were digested sequentially with 0.4% pronase E and 0.02% collagenase IA, or with 0.15% collagenase II alone, or sequentially with 0.4% pronase E and 0.02% collagenase II. We compared cell yield from each method. Cell viability by the most effective method was calculated and plotted. The morphology of cultured monolayer chondrocytes was recorded with a light microscope.
Results
Sequential digestion with pronase E and collagenase IA yielded 2566 ± 873 chondrocytes per mg wet cartilage, which was more effective than the other isolation methods (P = 0.018). The average chondrocyte viability could reach 84% ± 8% (n = 11). Light microscopic images showed typical chondrocyte morphology in monolayer cultures.