The formulation of novel calcium phosphate containing culture beads for cell therapy

Cell therapy has recently gained much attention as a novel treatment method for a range of diseases. Many early examples of mesenchymal stem cell use have focussed on infusion of a cell population and rely on the cells locating to the area of tissue damage. The development of implantable materials in the form of microcarriers to deliver cell populations to the site of injury could help enhance efficacy of treatment. Such carriers may also be used to expand cell populations \(in\) \(vitro\). In this thesis, a range of cell culture beads have been formulated using calcium phosphate ceramics, with and without the addition of a hydrogel such as gellan gum. The processing of the calcium phosphate (brushite) cement beads was shown to be critical to cell attachment, with the use of a crystallisation inhibitor in the formulation causing cell detachment. By conditioning the beads post manufacture or by using a process of granulation of brushite crystals, it was possible to generate beads that enable attachment and proliferation of the cells: a ~34 fold increase in the case of post treated beads and ~6 fold in the case of granulated beads. It was also shown that modification of gellan gum with nanoscale HA (nHA) at a concentration of 50 wt% allowed the control of mechanical properties by increasing yield strength and bulk modulus by four- and nine fold, respectively. Finally, it was shown that both ceramic and ceramic-hydrogel beads were conducive to bone formation when culturing MC3T3 pre-osteoblast cells in static and dynamic conditions, respectively