TVDD

Systemic Sclerosis (Scleroderma) is a chronic autoimmune disease affecting the skin and other organ systems e.g. kidney.  It is characterised by defects in immune cell response, vascular reactivity and heart failure (Raynaud's phenomenon) and fibrotic lesions.  This project focuses on the fibrotic aspect of the disease.  The fibrotic response involves transformation of fibroblasts into myofibroblasts leading to excessive deposition of collagen driven by inflammatory mediators released from B-lymphocytes.  Fibroblasts from scleroderma patients retain a memory for the diseased phenotype and can be maintained in culture.  The role of sphingosine 1-phosphate (S1P) in scleroderma has only recently been appreciated [1-3].  This project will investigate the mechanisms by which S1P promotes fibrosis using fibroblasts from healthy and scleroderma patients.  The involvement of S1P receptors (particularly S1P₂ and S1P₃) will be investigated using pharmacological antagonist and siRNA knockdown approaches, with specific focus on SMAD signalling and IL-6 formation. A similar approach will be used to investigate the involvement of Sphingosine kinase (the enzyme that catalyses the formation of S1P) and sphingosine 1-phosphate lyase (the enzyme that catalyses degradation of S1P). The objective will be to obtain information that informs upon possible therapeutic interventions that can either inhibit fibrotic signalling or induce apoptosis of dangerous myofibroblasts that are involved in disease progression.

Biochemical techniques include: sphingosine kinase activity assays, western blotting, immunofluorescence microscopy, healthy and scleroderma patient derived fibroblast cell culture, proliferation, apoptosis and differentiation assays.

1. Pattanaik, D., Brown, M., Postlethwaite, A.E. (2011) Vascular involvement in systemic sclerosis (scleroderma). J. Inflamm. Res. 4:105-25.
2. Pyne, S., Dubois, G. & Pyne, N.J. (2013) Role of sphingosine 1-phosphate and lysophosphatidic acid in fibrosis.  Biochim. Biophys. Acta. 1831, 228-238.
3. Pyne, S. & Pyne, N.J. (2011) Translational aspects of sphingosine 1-phosphate biology. Trends in Molecular Medicine 17, 463-472.