Dialysis & Renal Transplantation

BIOGRAPHY

Stephen H Powis

Academic positions:
- Professor of Renal Medicine
- Director of the Centre for Nephrology
- Medical Director of the Royal Free Hospital Hampstead NHS Trust

All industry positions (in last five years):
None declared

Research interests:
Professor Powis's main area of expertise is the genetics and biology of the human major histocompatibility complex (MHC or HLA region), the region of the genome that encodes the major transplantation antigens. The MHC also contains genes encoding a variety of other immune system proteins, and is associated with susceptibility to a large number of human diseases such as diabetes and rheumatoid arthritis. Other on-going research projects within his laboratory include work on pancreatic islet cell transplantation, studies of cytokine expression during the rejection of renal transplants, and studies on the genetic basis of polygenic renal disorders. Projects include:

1. Characterisation of the genetic basis of glomerulonephritis.
The aim of this project is to establish a national DNA bank for five forms of glomerulonephritis, which together represent a major cause of end-stage renal disease. These are minimal change nephropathy, membranous nephropathy, IgA nephropathy, lupus nephritis and renal vasculitis. Once established, the DNA bank can be utilized by investigators who wish to study the role of candidate disease genes in the pathogenesis of these disorders. The project has core funding from the Medical Research Council and the National Kidney Research Fund.

2. Characterisation of the intra-portal transplanted islet response to hypoxia.
Diabetes is a major cause of renal failure and a major cause of post-renal transplant morbidity. Although insulin can control diabetes, its use does not prevent long-term complications. Pancreatic islet cell transplantation offers a possible 'cure' for diabetes, but until recently it has not been clinically successful. However, recent advances in immunosuppressive drugs have dramatically improved results, with approximately 80% of patients remaining insulin-free one year post transplant. Unfortunately, each patient requires at least two islet transplants before becoming insulin-free. We are investigating the mechanisms through which islets implant within the liver after portal vein infusion, the usual clinical mode of islet transplantation. We have previously shown that hypoxia may play an important role in preventing engraftment and are now investigating the molecular basis for this observation.

Any other information:
Professor Powis is currently Chairman of the Joint Committee on Higher Medical Training (JCHMT) Specialist Advisory Committee (SAC) for Renal Medicine and a member of the Renal Association Executive Committee. He is a past Treasurer and Trustee of the British Transplantation Society and a former member of the UK Transplant Kidney Pancreas Advisory Group.