Immune cell death safeguards against autoimmune disease

September 6, 2012
Dr Daniel Gray and colleagues have discovered that immune cell death is an important safeguard against autoimmune diseases. Credit: The Walter and Eliza Hall Institute, Australia

Researchers at the Walter and Eliza Hall Institute have discovered that a pair of molecules work together to kill so-called 'self-reactive' immune cells that are programmed to attack the body's own organs. The finding is helping to explain how autoimmune diseases develop.

Dr Daniel Gray and colleagues from the institute's Molecular Genetics of Cancer division and the University of Ballarat discovered that the absence of two related proteins, called Puma and Bim, led to self-reactive accumulating and attacking many different body organs, causing illness. The research is published online today in the journal Immunity.

, such as type 1 diabetes, , and multiple sclerosis, develop when immune cells launch an attack on the body's own cells, destroying important body organs or structures. Around one in 20 Australians is affected by autoimmune conditions, most of which are with no cure.

Puma and Bim are so-called 'BH3-only' proteins that make cells die by a process called apoptosis. Defects in apoptosis proteins have been linked to many human diseases, including cancer and neurodegenerative disorders.

Dr Gray said one way the body protects against autoimmune disease is by forcing most self-reactive immune cells to die during their development. "If any self-reactive cells manage to reach maturity, the body normally has a second safeguard of switching these potentially dangerous cells into an inactive state, preventing them from causing autoimmune disease," he said.

"Until now, there has been debate about how important the death of self-reactive cells is as a protection against autoimmune diseases. Our research has identified two molecules that are needed for this process. We were able to use this discovery to show that the death of self-reactive immune cells is indeed an important protection against autoimmune disease development."

Dr Gray is now collaborating with researchers who have identified human gene defects linked to the development of autoimmune conditions. "We now know that self-reactive cell death is an important protection against autoimmunity," Dr Gray said. "The next stage of our work is to discover whether defects in the cell death process cooperate with other factors to cause human autoimmune disease."

Explore further: Researchers discover connection between allergic diseases and autoimmune diseases

Related Stories

B cells can act alone in autoimmune disease

August 7, 2008

B cells, the source of damaging autoantibodies, have long been thought to depend upon T cells for their activation and were not considered important in the initiation of autoimmune diseases like lupus or rheumatoid arthritis.

Potential autoimmunity-inducing cells found in healthy adults

December 22, 2008

It's not just patients with autoimmune diseases like lupus and rheumatoid arthritis (RA) that have self-attacking immune cells—healthy people have them too, according to a new report in the Journal of Experimental Medicine. ...

Researcher steps closer to understand autoimmune diseases

March 6, 2012

Understanding why immune cells, called T-cells, attack the body is vital in the war against autoimmune diseases like diabetes. University of Alberta researcher Troy Baldwin is a step closer to understanding why the body's ...

Recommended for you

Researchers gain new understanding of how neutrophils

August 31, 2016

As an arm of the innate immune system, white blood cells called neutrophils form the first line of defense against invading pathogens. Neutrophils spend most of their lives racing through the bloodstream, patrolling for bacteria ...

Barcodes show the blood family tree

August 24, 2016

By assigning a barcode to stem cells, researchers at Lund University in Sweden have made it possible to monitor large blood cell populations as well as individual blood cells, and study the changes over time. Among other ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.