The Use of Alginate to Inhibit Mineralization for Eventual Vascular Development

Bone is a complex tissue with a complex architecture and numerous types of cells. Bone can contain two different architectures (cortical and trabecular) and several cell types (osteoblasts, osteoclasts, osteocytes, neurons, and stem cells to name a few). Nutrient transport is extremely important for a tissue with such complexity in design and cellular population. Therefore, when considering tissue engineering or regenerative engineering, options for bone vascularization must be considered. Along with placement of the vasculature, conditions for vascular development should be of the utmost importance. Optimizing the tissue-engineered scaffold for vascular development can often go overlooked as researchers focus on bone growth and scaffold strength. In this study, we look at scaffold conditions that are best for vascular development in bone scaffolding. Specifically, we investigate how the presence of crystalized calcium phosphate on a scaffold surface affects the ability of vascular endothelial cells to proliferate and differentiate for the eventual production of blood vessels. In addition, we use alginate as a way to maintain a “vascular friendly” surface inside of a mineralized scaffold. The results show that vascular endothelial cells prefer a non-mineralized scaffold and that the presence of alginate on surfaces during mineralization of a scaffold protects that surface from mineralization, making it capable of producing vasculature from seeded vascular endothelial cells. A piece of bone contains many structures, tissues, and cell types. In order to support them all, a bone has an extensive network of blood vessels. This makes the formation of useable blood vessels important for tissue engineering. In this study, we investigate how calcium phosphate formation affects blood vessels inside of bone scaffolds. Specifically, we investigate how calcium phosphate on a scaffold affects blood vessel formation in bone tissue engineering scaffolds. In addition, we use alginate to enhance vessel formation in the scaffolds. The results show that vessel formation is optimal without calcium phosphate on the scaffolds.