Bio-responsive materials for tissue regeneration

The field of tissue engineering brings together researchers from a broad range of multidisciplinary backgrounds with the common aim of pursuing continuous improvement in biomedical innovation. Advances in tissue repair and regeneration attempt to meet the gold standard offered by autografting while avoiding the issues associated with tissue harvesting. Over time, focus moved from the use of allografts and synthetic grafts (non-degradable) towards exploring the potential for engineered ‘living grafts’ to address tissue diseases and the treatment of organ failure. However, it is clear that tissue-engineered implants used in a wide range of therapeutic applications still require further improvement. Recent recognition of the limitations and challenges associated with tissue regeneration, has triggered a shift towards ready-to-use implants that can induce biological repair processes and this has highlighted the need for biomaterials that can promote optimised biological response. Rather than developing biomaterials for tissue replication and substitution in classical tissue engineering, there is a new focus on creating biomaterials that are bio-responsive and hence capable of guiding tissue and organ repair. Successful routes involve mimicking natural processes that occur during regeneration. This can be achieved through the use of emerging engineering and technological advances, with careful control of the intrinsic physical and chemical cues from the as-fabricated materials (e.g. modified biochemical motifs, stiffness, anisotropy etc) or stimulated by extrinsic factors (e.g. pH, heat, light, metabolites etc).