Recent areas of research have explored the use of stem cells to repair the damaged sphincter through injection of these cells into the external anal sphincter in animal models and human subjects. The studies to date have been limited with variable improvements in function and large gaps in knowledge remain regarding how these cells impact on healing. 

Zoey Robinson, Registrar Obstetrics and Gynaecology at the Royal United Hospital Bath NHS Trust, applied for an opportunity to undertake an EBI Clinical Primer project at the University of Bristol in the group of Professor Anthony Hollander, to try and develop a ‘delivery system’ for these cells to the site of injury within an in vitro environment. This system consisted of stem cells seeded onto a biodegradable collagen scaffold which was introduced as a ‘stem cell bandage’ to bring together artificially severed ends of a sphincter ring. The degree of integration of the scaffold and separated muscle was found to be greater with the presence of the stem cells. 

Further development of this model will include the use of maternal stem cells isolated from the mother’s placenta to demonstrate how it is possible to use a readily available and non-invasive source of stem cells. 

The research has determined feasibility of such an approach to aid healing of the external anal sphincter. If further development of this method is successful this technology can be translated to the repair processes already used for obstetric injury to the external anal sphincter in humans thus could act as a future potential therapeutic treatment. 

Zoey is hoping to continue her research in this area in collaboration with Dr Wael Kafienah, University of Bristol, School of Cellular and Molecular Medicine, and in partnership with Cook Myosite Inc (company based in Pittsburgh, USA).