Exploring natural sources for tissue engineering developments

Nature has evolved a number of strategies (material-structure) to generate outstanding functional materials that are typically multifunctional, dynamic and environmentally responsive (1). The conjugation of natural principles/materials/architectures is a new approach to tailor multifunctional material systems for biotechnological applications (2), including biomaterials. In particular, interest in naturally derived polymers includes the possibility of constructing multi-functional systems that can be manipulated in composition and structured for novel biotechnological uses in the field of tissue engineering, i.e., to mimic the tissue environment (chemistry/patterning/architecture/mechanical properties) required for cellular regeneration. The presentation will focus on the function-structure relationships and processing of natural materials for the fabrication of cells-responsive devices with applicability in regenerative medicine. As examples, silk-based structures (from Lepidoptera cocoons), obtained by processing silk fibroin isolated from different sources, fish scales (Lates calcalifer) and collagen obtained from fish scales will be presented and discussed Silk-based matrices have attracted a lot of attention as bioactive proteins for biomedical applications (3), as well as model fibres to understand other structural polymers. However, conformation of silk fibroin depends on the processing conditions and these in turn affect the materials biological and physical properties (4). Marine organisms-derived collagen displays peculiarities in terms of properties and functions and that have been recently suggested as materials for regenerative medicine applications. CONCLUSIONS: Biopolymers are multicomponent and multifunctional, building block based and assembled with bottom-up approaches and arranged in complex hierarchical patterns, from sub-molecular to macro-level, and always correlated to a specific function. There are many examples of natural materials that exhibit unique properties, and fibroin and collagen have become some of the most promising materials for temporary artificial extracellular matrices for tissue engineering applications.