PLGA used as a component in an anti-inflammatory bone scaffold

PolySciTech (www.polyscitech.com) provides a wide array of PLGA polymers and related biodegradable polyesters.  Recently PLGA has been used along with other components to generate a bone scaffold that allows for repairing large defects or substantial fractures.  This scaffold was loaded with an anti-inflammatory drug which were found to aid in the healing process when loaded at the correct dose. Read more: Sidney, Laura E., Thomas RJ Heathman, Emily R. Britchford, Arif Abed, Cheryl V. Rahman, and Lee D. Buttery. "Investigation of localised delivery of diclofenac sodium from PLGA/PEG scaffolds using an in vitro osteoblast inflammation model." Tissue Engineering ja (2014). http://online.liebertpub.com/doi/abs/10.1089/ten.TEA.2014.0100

                                   

“ABSTRACT: Non-union fractures and large bone defects are significant targets for osteochondral tissue engineering strategies. A major hurdle in the use of these therapies is the foreign body response of the host. Herein, we report the development of a bone tissue engineering scaffold with the ability to release anti-inflammatory drugs, in the hope of evading this response. Porous, sintered scaffolds composed of poly(DL-lactic acid-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) were prepared with and without the anti-inflammatory drug diclofenac sodium. Analysis of drug release over time demonstrated a profile suitable for the treatment of acute inflammation with approximately 80% of drug released over the first 4 days and a subsequent release of around 0.2% per day. Effect of drug release was monitored using an in vitro osteoblast inflammation model, comprised of mouse primary calvarial osteoblasts stimulated with proinflammatory cytokines interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Levels of inflammation were monitored by cell viability and cellular production of nitric oxide (NO) and prostaglandin E₂ (PGE₂). The osteoblast inflammation model revealed that proinflammatory cytokine addition to the medium reduced cell viability to 33%, but the release of diclofenac sodium from scaffolds inhibited this effect with a final cell viability of approximately 70%. However, releasing diclofenac sodium at high concentrations had a toxic effect on the cells. Proinflammatory cytokine addition led to increased NO and PGE₂ production; diclofenac sodium releasing scaffolds inhibited NO release by approximately 64% and PGE₂ production by approximately 52%, when the scaffold was loaded with the optimal concentration of drug. These observations demonstrate the potential use of PLGA/PEG scaffolds for localised delivery of anti-inflammatory drugs in bone tissue engineering applications.”