New mechanism for autoimmune diseases

Researchers from Monash University have “answered one of the biggest questions in autoimmune disease” by determining the mechanism underlying the key genetic risk factors that lead to a raft of autoimmune diseases including: Crohn’s disease, multiple sclerosis, type 1 diabetes, ulcerative colitis, rheumatoid arthritis and various forms of kidney disease.

The question they set out to answer was how (and why) different immune molecules can alter an individual’s genetic likelihood of succumbing to one of the many autoimmune diseases that afflict over a million Australians.

Professor Richard Kitching of the Monash Centre for Inflammatory Diseases explains that while our immune system learns to fight off different foreign invaders over time, “this sometimes goes wrong and our immune system recognises parts of our own body as being foreign. This leads to autoimmune disease.”

Co-author Professor Jamie Rossjohn from the Monash Biomedicine Discovery Institute, said: “Certain immune molecules, called HLA molecules, are associated with an increased genetic risk to cause autoimmunity, whereas other HLA molecules can protect from disease.”

The Monash team’s research focused on mechanistic evidence of the basis of protective and disease-causing HLA molecules, resulting in a new understanding of why some people develop autoimmune diseases, while others are protected.

“We have known that in autoimmune diseases there are T cells that make us susceptible to disease and T cells that protect us from disease. Now we know how this happens, it opens the field for new and more targeted treatments to specific diseases,” said Professor Kitching.

This is the first time researchers have been able to identify the causes of aberrant immune systems and paves the way for new lines of research that could lead to personalised therapies with new and novel treatments.

“We have answered one of the biggest questions in autoimmune disease,” said Professor Rossjohn, a researcher at the newly established Monash Biomedicine Discovery Institute, which has brought over 120 internationally renowned research teams together to relieve the future burden of disease.

Professor Kitching said, “These particular protective immune cells are specific and are extremely powerful. So, if we can encourage them to develop in the body, or expand people’s cells outside the body and inject them back into those with disease, this could result in better and more targeted treatments for autoimmune diseases.”

Published in Nature, this research was also supported by the Australian Research Council Centre of Excellence in Advanced Molecular Imaging, which is based at Monash University, while collaborating with the University of Queensland, University of Melbourne, University of New South Wales and La Trobe University.

Image credit: Vannette Tran