Pathway intervention therapy for EBS Dowling-Meara (Lane 3)

What did this project achieve?

People with EBS, especially the severe Dowling Meara type, have very fragile skin that blisters easily on mechanical stress. Our lab has developed several disease model cell lines and cell culture stress assays which we have been using to study and model EBS in the lab, without the need for direct patient testing. We discoverd that EBS-mimicking cells, that have the same disease-causing mutations as the patients, exist in a continously stressed state, even before additional mechanical stress. This led us to the idea of a mechanism that may directly link Dowling-Meara EBS mutations that caouse damage keratin filaments inside the skin cells with the clustered and spreading blisters that affect the patients. We found evidence suggesting that if we could reduce the formation of the abnormal microscopic keratin lumps, or aggregates, that form inside EBS cells, we should be able to reduce the cell stress and return the skin cells to a much resilient state.

This project (LANE3) was carried out in parallel with anohter DEBRA-funded project on druc discovery (LANE2). The two projects complement and support each other. The current project aimed to develop assay systems that are stringent, reproducible and robust enough to convince industry partners of the value of co-developing candidate compounds discovered in the first project (LANE2). The pharmaceutical industry is very cautious about investing in research, and exremely clear and reproducible findings would be needed to convince that our candidate drugs would likely have sufficient beneficial effects on EBS fragile skin to make it worth their investing in collaborations with us to fund and support developing a treatment for EBS. We believe we have succeeded in these aims. Using our new diesease model cell lines that we show to be very reproducible, we have shifted away from what was a rather subjective operator-oriented way of evaluating the degree of diesease-associated keratin protein aggregation in EBS-mimetic cells. We have a developed and validated a EBS-mimetic cell stress reporter system using an automated image analysis system that produces quantifiable resulsts and is suitable for high throughput compund library screening. We have validated the reporter cell line, culture and assay protocols with a publicly available small compound library and shown that the system works reproducibly and confirms the earlier subjective findings described in LANE2. Moreover, we have identified anohter class of compounds from this library that are new candidates for keratin aggregate reduction and EBS cell phenotype rescue. By following this approach of intervening in the mutation-activated stress response of the skin cells, we have provided proof-of concept that 'Pathway intervention therapy for EBS' is potentially doable, and may indeed be cheaper and quicker than conventional gene therapy approaches.