Avian Egg: A Multifaceted Biomaterial for Tissue Engineering

Avian eggs offer a natural and environmentally friendly source of raw materials, and many of their components hold great potential in tissue engineering. An avian egg consists of several beneficial elements: the protective eggshell, the eggshell membrane, the egg white (albumen), and the egg yolk (vitellus). The eggshell is mostly composed of calcium carbonate and has intrinsic biological properties that stimulate bone repair. It is a suitable precursor for the synthesis of hydroxyapatite and calcium phosphate, which are particularly relevant to bone tissue engineering. The eggshell membrane is a thin protein-based layer with a fibrous structure composed of several valuable biopolymers, such as collagen and hyaluronic acid, also found in the human extracellular matrix. As a result, the eggshell membrane has found several applications in skin tissue repair and regeneration. The egg white is a protein-rich material that is under investigation for the design of functional protein-based hydrogel scaffolds. The egg yolk, composed mainly of lipids, also contains diverse essential nutrients (e.g., proteins, minerals, and vitamins) and has potential applications in wound healing and bone tissue engineering. This review summarizes the advantages and status of egg components in tissue engineering and regenerative medicine as well as their current limitations and future perspectives.