Understanding the mechanisms of epidermal barrier damage and repair using 3D skin equivalent models
The epidermis of the skin provides an essential barrier between our bodies and the external environment through the formation of a dense cornified layer of cross-linked proteins and lipids at the surface of the skin. Chemical insult or impaired lipid synthesis can damage the cornified layer and lead to barrier dysfunction; however the fundamental relationships between lipid content and barrier biophysical properties remains poorly defined. In addition, there is a need for improved human-based experimental models for investigating lipid function and barrier repair in vitro, and for the evaluation of new therapeutic compounds.
The aim of this PhD studentship is to develop a 3D organotypic skin model of impaired lipid synthesis in order to dissect the functional relationships between lipid synthesis, barrier mechanics, and tissue repair. In addition, this platform will be used to evaluate lipid mimetic compounds developed by the GSK Skin Health group. The project will employ shRNA to stably knockdown key enzymes involved in lipid biosynthesis and advanced biophysical methods to characterise the effects of impaired lipid synthesis and the response to lipid-mimetic treatments on skin barrier function. The project will consist of three major objectives.
1. Build and characterise 3D skin models of impaired lipid synthesis: Keratinocyte cell lines with stable knockdown for key enzymes involved in lipid biosynthesis will be used to construct 3D organotypic models, and the effects on tissue biophysics will be assessed by atomic force microscopy (AFM), while terminal differentiation and barrier function will be examined by immunohistochemistry and permeability assays, respectively.
2. Develop quantitative relationships between lipid content and epidermal mechanics: Lipidomic profiling of human skin equivalents lacking different components of the lipid biosynthesis pathways will be performed by mass spectrometry and correlated with biomechanical data to develop quantitative and predictive models of the relationship between lipid content and skin barrier function.
3. Assess the effects of different lipid-based compounds on the biophysical properties and cellular functions within the model system: The genetic skin models will next be treated with lipid-based protective compounds, with or without chemically-induced barrier damage, and the effects on the biophysical properties and cellular phenotypes will be analysed.
The successful completion of this project will provide fundamental insights in the mechanistic relationships between lipid content and epidermal barrier function. These findings will have a significant impact on our understanding of normal skin function and the consequences of lipid deficiencies. Importantly, this new knowledge could help identify new therapeutic targets for the treatment and repair of skin barrier damage.
Application Deadline Applications must be complete, including both references, by 11th January 2019 at 5pm
Fully funded place including home (UK) tuition fees and a tax-free stipend in the region of £16,777. Students from the EU are welcome to submit an application for funding, any offers will be subject to BBSRC approval and criteria.