Chris is a member of the Nuffield Department of Medicine and combines research with clinical practice. His current area of research interest involves studying how cells and organisms (from worms to man) respond to low oxygen availability. When oxygen levels fall the body makes a number of adaptive responses to try and compensate. These include changes in the way in which oxygen is transported around the body, for example by increasing the number of red blood cells and blood vessels, and changes in the body's metabolism so that energy production can be maintained even when the oxygen supply is low. These changes can be entirely appropriate, for example allowing a mountaineer to perform well at altitude, or leading to the development of collateral blood vessels after a main blood vessel has been blocked. Conversely, in cancer the tumour cells use similar changes to facilitate their survival, to the detriment of the patient.
Over the last 17 years Chris, and his colleagues, have elucidated the molecular basis for this adaptive response which involves a transcription factor called HIF (Hypoxia-inducible factor), regulated by enzymes from a family known as oxoglutarate-dependent dioxygenases. Research efforts are now concentrating on trying to see how the system could be manipulated to help patients since an enhanced activity of this system might well be beneficial to patients with ischaemic disease, where the blood flow to tissues is limiting. Alternatively, blockade of the system might become a component of future cancer therapies. To help with drug development Chris and his colleagues, Peter Ratcliffe (Magdalen), Chris Schofield (Hertford) and Patrick Maxwell (now at University College, London) established ReOx Limited, an Oxford University spinout company which has been involved in an exciting research collaboration with Amgen Inc.
In his clinical work Chris looks after patients with a variety of acute and chronic kidney diseases, including those with complete kidney failure who are kept alive by dialysis or transplantation. He does two outpatient clinics every week and acts as duty consultant for the Oxford Kidney Unit for six weeks each year.