Application of Chitosan-Based Biomaterials in Tissue Engineering - Chitosan Based Hydrogels: Functions and Applications - page 434

interactions. The scaffold should not inhibit diffusion, which is especially relevant when
culturing large amounts of cells for transplants, as is necessary for clinical applications.
Therefore, the pores of the chitosan-based scaffold have a very important role in the forma-
tion process of new cartilages. On the basis of a chondrocytes diameter of approximately
10 μm, it is believed that a truly interconnecting porous structure with an average pore
diameter of 70 μm would have allowed a substantial number of cells to migrate to the inte-
rior region of the scaffold. Chondrocytes cultured on chitosan scaffolds with pores <10 μm
in diameter formed a film covering the surface of the scaffolds and produced small amounts
of matrix ( cf. Figure 9.27a) [133]. In this system, chondrocytes migration and tissue ingrowth
within chitosan scaffolds are very difficult. Chitosan scaffolds containing larger pores
appeared to contain more cells surrounded by the ECM. Cells penetrated the pores of chi-
tosan scaffolds, especially in the group presenting the largest pores. The distribution of
cells appeared more uniform throughout scaffolds as pores increased in size. Macroporous
Figure 9.27
Histology (H&E, ×40) and SEM of chitosan/chondrocytes constructs after 4 weeks of dynamic culture. (From
GriVon, D. J. et al. 2006. Acta Biomater 2: 313-320. With permission.)