Engineering human skin fibroblasts with an orthogonal transcriptional circuit conferring glucose-responsive insulin release

In this project we will take a novel approach - exploiting the latest tools of synthetic biology to create synthetic transcriptional regulators and promoters to construct an orthogonal transcriptional circuit enabling glucose sensing and controlled release of corresponding levels of insulin. Such a circuit will be engineered into human dermal fibroblasts, which are an accessible autologous cell type amenable to genome engineering.

Expertise in programmable transcription factors, primary human cell culture and synthetic regulatory circuits/promoters will underpin this project and enable us to define the optimal circuit design for effective glucose sensing and insulin release, with appropriate feedback circuits. We will exploit the CRISPR/Cas system and TALE-based transcriptional activators and repressors to create novel synthetic transcription factors and these will be used to construct the synthetic circuit.

The development of our glucose-responsive circuit will provide a means of producing insulin in a highly controlled manner. The circuits will be tested in human fibroblasts, an easily-obtainable human cell type that may be expanded long term in culture and can be readily genetically manipulated. Finally, once the circuit has been validated in vitro with regards to glucose sensing and insulin production, we will test how well this works in vivo following subcutaneous transplantation into immunocompromised mice. In the longer term, engineering patient-derived fibroblasts to produce insulin will allow cells to be grafted back onto the patient without the use of harsh immunosuppressive drugs or encapsulation devices.