Chronic inflammatory diseases
Coeliac disease
Coeliac disease afflicts about one per cent of the population – more than 200,000 Australians – and is caused by an allergic response to gluten, a protein found in wheat, rye and barley grains. The inflamed immune system damages the lining of the small intestine, hampering its ability to absorb nutrients from food. Individuals with this debilitating lifelong condition can develop other problems, such as osteoporosis. The only currently available treatment is a diet free of gluten. Dr Bob Anderson and Dr Jason Tye-Din from the Immunology division has made significant advances in understanding what part of the gluten protein causes this disease and is developing a vaccine to provide patients with a greater quality of life and relief from symptoms.
Type 1 diabetes
In healthy individuals, beta cells in the pancreas produce a hormone called insulin that promotes the breakdown of glucose by the body’s cells. In patients with type 1 diabetes, the body’s immune system attacks the insulin-producing beta cells. It is still unclear what triggers this abnormal reaction, although there is an important genetic component. It takes a number of years to destroy all the beta cells but, when there is no longer enough insulin, dangerously high levels of glucose accumulate in the blood. Type 1 diabetes usually occurs in individuals under 30 but can strike at any age.
In Australia, more than 100,000 people have type 1 diabetes; there are 5000 new cases each year and the incidence is increasing by four per cent per year. People who develop type 1 diabetes need up to four injections of insulin daily for the rest of their lives. There are also many long-term complications – for example, type 1 diabetes is the major single cause of adult blindness and kidney disease and an important contributor to cardiovascular disease. The cost to our community in financial terms is estimated to be at least $1.5 billion per annum and the personal and societal cost is inestimable.
Professor Len Harrison and his team in the Immunology division have been working for many years to understand how the immune system destroys the insulin-producing cells in order to prevent and cure type 1 diabetes. They have identified key molecules involved in stimulating the autoimmune attack on beta cells and developed a reliable procedure for pre-clinical diagnosis of disease in children at genetic risk. Excitingly, they have now launched a clinical trial of a preventative vaccine.
See WEHI.TV for a short animation explaining type 1 diabetes.
Rheumatoid arthritis
Another debilitating autoimmune disease is rheumatoid arthritis. This condition afflicts more than one per cent of Australians and is a major cause of disability and chronic pain. In rheumatoid arthritis, the joints of the body become inflamed, stiff, swollen and, eventually, eroded, often limiting a patient’s ability to live a full life. Rheumatoid arthritis is estimated to cost the nation about $6 billion every year in direct and indirect costs.
Research conducted by Professor Ian Wicks in the Inflammation division has revealed that rheumatoid arthritis involves hormones known as G-CSF (granulocyte colony stimulating factors) and GM-CSF (granulocyte-macrophage colony stimulating factors). These hormones, discovered at the Walter and Eliza Hall Institute by Professor Donald Metcalf and his collaborators, normally promote white blood cell production. When misdirected by the body’s immune system however, they can greatly amplify inflammation in the joints. Professor Wicks and his team are investigating ways of regulating the actions of these molecules and reducing the severity of inflammation and joint damage in rheumatoid arthritis.
Transplantation
The transplantation of body organs not only prolongs life but also improves quality of life. To prevent rejection of such organs by the recipient’s immune system, strong drugs are currently required. These drugs, although efficacious, have serious side effects. Moreover the immune system throughout the whole body is unnecessarily suppressed. Research in the Immunology division is showing progress at finding approaches that replace or reduce the use of these drugs and act only at the site of the transplant.