Hard-tissue replacement & Bone tissue engineering

Principal investigator: Joost DE BRUIJN

Adult stem cells grown on a 3D biomaterial scaffoldProfessor de Bruijn’s research interests relate to hard-tissue replacement materials, bone tissue engineering and bioreactors to expand adult bone marrow derived stem cells. Regarding hard-tissue replacement materials, de Bruijn’s group has recently developed a group of unique three-dimensional calcium phosphates that can induce bone formation after subcutaneous or intramuscular implantation in rats, rabbits, dogs and goats. The presence of a calcium phosphate containing microporous surface structure has been shown to be critical for this bone-inducing ability.

X-ray microtomography of tricalcium phosphate particles on which adult goat bone marrow cells were seeded prior to 12 week intramuscular implantation. Picture kindly provided by Dr. Graham Davis, Dental Biophysics Section, QMULFundamental research in this area focuses to the manufacturing and characterisation of different types of bone-inducing ceramics, as well as evaluating mesenchymal stem cell responses to the bone-inducing and non bone-inducing materials in vitro and in vivo environments, in order to unravel the mechanisms of material-directed bone induction. This knowledge will enable the design of new intelligent scaffolds for bone replacement. With regard to the multi-disciplinary bone tissue engineering programme, fundamental and applied research is directed towards developing methods to produce tissue engineered, living bone equivalents that can be applied during (minimal invasive) surgery. A strong focus is placed on both biomaterial science and cell culture technology. The biomaterials science part relates to developing appropriate biocompatible scaffolds (e.g. sub-millimetre calcium phosphate particles) and injectable carrier systems (amongst which reverse thermal polymer systems) that are suitable for osteogenic cell attachment and differentiation. The biological part involves the harvesting, culture and characterisation of (human) bone marrow derived mesenchymal stem cells.