Recombinant elastin for biomedical applications-Advances in molecular design, expression platforms, and purification strategies: A review.

Elastin is an essential extracellular matrix protein that provides elasticity and structural resilience to dynamic tissues such as skin, blood vessels, and lungs. Its unique reversible phase transition behavior has inspired growing interest in biomedical material design. Conventional sources-tissue extraction and chemical synthesis-are hindered by low yield, high cost, and biosafety risks. Recombinant elastin offers a scalable, programmable alternative with precise sequence control, tunable properties, and excellent biocompatibility. This review summarizes elastin's biological roles, structural features, and functional mechanisms, with emphasis on recombinant design strategies, expression platforms, and purification methods. Prokaryotic (e.g., E. coli), eukaryotic (e.g., Pichia pastoris), and plant-based systems are compared in terms of yield, post-translational modification capacity, and scalability. Purification approaches-including inverse transition cycling, affinity chromatography, multi-step integration, and organic solvent extraction-are evaluated for efficiency, purity, and industrial applicability. Key biomedical applications, such as drug delivery, 3D bioprinting, bone tissue engineering, and skin regeneration, are highlighted. Finally, current challenges-including achieving medical-grade purity, enhancing soluble expression, and meeting regulatory standards-are discussed alongside prospects for clinical and industrial translation. This synthesis aims to inform the rational design and large-scale production of next-generation elastin-based biomaterials.