Chondrocytes Scalable Expansion And Engineering Of Cartilage With Beta-TCP And Liquid Collagen

Just because cartilage has limited self-renewal capability and the amount of cartilage available for autologous transplantation is limited, the treatment of traumatic or congenital cartilage defects is limited and an estimated one million people per year are waiting for treatment of cartilage defects. Tissue engineering approaches offer new possibilities for functional restoration of the damaged or lost tissue. In this study, we have done a random search at expansion of chondrocyte and engineering of cartilage.1. The condrocytes isolated from human fetal epiphysial cartilage was dynamically planted on the plane microcarriers MicroHex or Cytodex-3 in the RCM^TM bioreactor through an intermittent ratory regime. The redifferentiation was evaluated via a novel pellet cultures which was more like three-dimensional culture system and the two diffenrent mediums were used. The effect of expansion were assessed via cell viability analysis, proliferation cycle analysis, SEM observation, and compared with expansion on T-flask.2. And the chondrogenic potential of expanded cells seeded in beta-TCP scaffolds,cultured for 14 days in vitro, and subsequently implanted subcutaneously in nude mice,was assssed. It were analyzed by H&E staining, Safranin-O staining, collagen type II immunhistochemistry staining, and so on.3. Engineering a cartilage with special shape in vitro via chondrocytes mixed with liquid collagen. Chondrocytes were mixed with liquid rat tail collagen, after centrifugation, the mixture was pipetted into cylinder casting mold to construct a cartilage with special shape. Mechanical properties of these constructions were detected after 7d and 14d culture period, and implantation subcutaneously in nude mice was also carried Their paraffin sections were stained by picric acid-sirius red staining. The 14d cartilage paraffin sections were stained by toluidine blue and collagen type II immunhistochemistry.The main results and conclusion were as following:1. Chondrocytes remained viable during microcarrier culture and yielded doubling times (2.54±0.33days of Cytodex-3 microcarrier and 3.81±1.61days of MicroHex microcarrier) comparable to T-flask expansion (3.61±0.49days). It suggests that RCM^TM- Cytodex-3 was an effective system for human fetal chondrocyte expansion.