4a. Scaffold-Based Tissue Engineering

Biodegradable natural hydrogels made from biogenic proteins (e.g., collagen, gelatin, and fibrin) and polysaccharides (e.g., alginate and hyaluronic acid) are commonly utilized as scaffolds in tissue engineering (Fig. 4a.1). However, ECM-derived animal proteins are rarely used by researchers because of the potential immunoreaction or infection [4-6].