Three-Dimensional Co-Cultures of Osteoblasts and Endothelial Cells in DegraPol Foam: Histological and High-Field Magnetic Resonance Imaging Analyses of Pre-Engineered Capillary Networks in Bone Grafts

Tissue engineering of bone grafts was addressed in a critical-sized model on the chick chorioallantoic membrane model, using DegraPol (R) foam as scaffold material. The scaffolds were seeded with cultures of human osteoblasts and human endothelial cells, respectively, or with a co-culture of the two cell types (control: no cells). In vitro samples (7 days cultivation) and ex vivo chorioallantoic membrane model samples at incubation day 15 were analyzed by high-field magnetic resonance imaging (MRI) and histology. The co-culture system performed best with respect to perfusion, as assessed by contrast-enhanced MRI using gadolinium-diethylene-triamine-pentaacetic acid (DTPA). The scaffold seeded by the co-culture supported an increased vascular ingrowth, which was confirmed by histological analysis. DegraPol foam is a suitable scaffold for bone tissue engineering and the MRI technique allows for nondestructive and quantitative assessment of perfusion capability during early stages of bone forming constructs.