'Silky' bones
Stem cell research combined with the development of novel implantable biomaterials hold great promise for tissue repair and regenerative medicine. Tissue engineering constitutes an emerging new technology for tissue replacement. Especially in the case of bone, there is growing clinical need for the development of new graft replacement materials. These have the potential to alleviate many problems encountered by using wires, metal plates or bone allografts. The implantable materials have to meet certain mechanical and structural requirements, such as full absorption, strength and resilience. Also, they need to be capable of guiding and encouraging tissue regeneration, and allowing the growth and expansion of tissue stem cells. The 'Development and evaluation of mineralized silk based composites for orthopaedic applications' (Silkbone) project set out to develop a biomaterial made of proteins from silk fibres as the basis for bone scaffold. The consortium of European scientists developed propriety processes to process silk fibres, quality evaluate proteins and incorporate them in three-dimensional (3D) porous scaffold structures. These proteins shared great similarity to proteins found in natural bone and the matrix created demonstrated high resilience and resistance to compressive forces. The unique 'biomimetic' properties of the resulting bone substitute material make it ideal for use in various orthopaedic applications, including bone replacement and revision procedures. These can be used to treat fractures resulting from osteoporosis and bone lesions in cancer patients. The technology of silk proteins was implemented in the development of other implantable materials for cartilage repair and wound healing, as well as nerve regeneration. Processes for stem cell growth and assays for biocompatibility of transplantable materials were streamlined, offering invaluable expertise to the consortium small and medium-sized enterprises (SMEs). Silkbone project achievements significantly contributed to the market of novel implantable biomaterials. Successes in this area will facilitate the wider application of this technology for regenerative medicine.
