The second most transplanted tissue
The challenges of an ageing population are broad however skeletal conditions such as osteoporosis and fracture are a growing problem. In addition, bone is a clinical necessity for orthopaedic, maxillofacial and plastic disciplines with graft typically being taken from the iliac crest. Problems with donor site morbidity and FDA warnings over the use of growth factors (BMP-2) are pushing the development of tissue engineered alternatives.
Within academia, typical approaches to stem cell/bone research involve complex bioreactor systems or specific osteogenic media. Such perfusion systems are prone to leakage or sterility issues and are difficult to scale whilst reagent costs can be prohibitive.
In contrast the Nanokick bioreactor mechanically converts stem cells into mineralising bone cells. This negates the need for specialist media or growth factors, offering a significant reduction in reagent costs and safer clinical use.
Lab grown bone
The sensitivity of cells to their mechanical environment, even at the nanoscale, is a crucial factor in tissue development. This is perhaps best demonstrated in bone where increased loading (e.g. during excercise) can lead to increases in density whereas reduced loading (e.g. during spaceflight) can reduce density. In an effort to understand these cellular processes a team of researchers from the University of Glasgow and the University of the West of Scotland have developed a new technique- nanokicking, using nanoscale vibration to manipulate the behaviour of cells. As a core example, mesenchymal stem cells can be taken from adult patients (e.g. extracted from bone marrow) and prompted to form bone building cells – osteoblasts.
The process offers many possibilities from development of cell-based assays for skeletal conditions to production of personalised skeletal autograft. Huge scope exists here to grow bone grafts from a patients own stem cells for tissue repair/replacement, in addition to treating conditions such as osteoporosis. This field of research is entirely new and the breadth of scope of nanokicking has not yet been fully realised.
The Nanokick system
The expansion of interest in nanokicking has led to the development of the Nanokick bioreactor. Due to the precise levels of vibration used, a unique collaboration between stem cell engineers (University of Glasgow) and gravitational wave physicists (University of the West of Scotland) has been developed. Research prototypes can stimulate six-well plates loaded with mesenchymal stem cells and reproducibly induce osteogenesis and mineralisation. The effect works both in 2D and 3D culture (collagen gel) allowing the potential for tissue engineered bone graft.
The bioreactor has been designed by researchers, for researchers with simplicity in mind. It is modular, allowing scalability for high throughput processes and compact for use within standard incubators. Disposables, resembling tissue culture plates, will allow familiarity for academic use. This also increases sterility and drastically reduces failure rates when compared to perfusion bioreactors which often autoclave and reuse components.
In terms of reagent costs, the use of basal, rather than osteogenic media can reduce costs by 90% in our system. Additionally, the ability to culture cells in 3D will allow increased quantities of osteoblasts to be produced per batch, again allowing scalable cell production. Finally, the removal of osteogenic chemicals will ensure that the resultant cells are a clean slate for applications such as therapeutic testing.