Scientists from the Australian National University (ANU) have discovered that a gene mutation is responsible for causing psoriasis – a chronic inflammatory skin disease that causes patients to develop red, scaly and itchy patches all over their body.
According to ANU researcher Dr Chelisa Cardinez, if there are two copies of this mutated gene (known as IKBKB), psoriasis patients may go on to develop psoriatic arthritis, leaving them with joint pain, stiffness and swelling. Thanks to a world-first discovery from ANU, scientists now know what causes the progression from a skin-only disease to a skin and joint disease.
It is hoped the findings will lead to improved diagnosis and treatment for patients with psoriasis and psoriatic arthritis – conditions that patients say cause stigma in the community.
Using a mouse model, we found that this mutation led to an abnormal function in a group of immune cells known as regulatory T cells.
These cells are usually considered the guardians of the immune system. However, we found that this mutation alters the function of these cells, causing them to contribute to inflammation and promote the onset of the disease.”
Dr Chelisa Cardinez, ANU John Curtin School of Medical Research (JCSMR)
Rebecca Davey is one of at least 500,000 Australians living with psoriasis. She also happens to have psoriatic arthritis and says the stiffness and pain she feels when she gets out of bed in the morning can be extreme.
“People don’t understand the debilitating effects these conditions can have on the individual and indeed on a whole family when someone is in constant pain, has poor sleep from the pain and feels constantly tired,” Ms Davey said.
“My psoriatic arthritis medications have greatly reduced the larger outbreaks on my skin, but you have to consider everything you put on your skin and the fabrics you wear. As a former nurse, even the constant hand washing required for the job would cause my skin to flare up. It’s one of the reasons I no longer work in the hospital system.”
Psoriasis and psoriatic arthritis are forms of autoimmune disease. These types of diseases occur when the immune system attacks healthy cells after mistaking them for a threat. According to Arthritis Australia, three in 10 Australians with psoriasis develop psoriatic arthritis.
Although there is no cure for psoriasis, there are treatments that can help manage the condition. In October 2023, the Pharmaceutical Benefits Scheme (PBS) registered a new, subsidized drug for Australians living with severe psoriasis.
Ms Davey, who is also Chief Executive of Arthritis ACT, says it is important to break down the stigma associated with these conditions. She says psoriasis is very misunderstood in the community.
“So many people are blamed for having poor hygiene because of the plaques or even just small skin lesions as they break out. It’s not the person’s fault that their skin is the way it is. Psoriasis is a painful, debilitating condition,” she said. .
“I had no idea what was causing my hands to flare up all the time. Our poor GPs often fail to recognize these conditions early.
“In regional and rural areas there is a drastic shortage of specialists in both dermatology and rheumatology to diagnose and treat these conditions and people can wait over a year for an appointment if their symptoms are less dramatic.
“We need to raise more awareness of invisible disabilities such as those created by these conditions. A person may look fine on the outside, but they are actually struggling on a daily basis.”
Dr Cardinez said: “Studies have shown that delays in the diagnosis of psoriatic arthritis are associated with worse clinical outcomes for patients. Therefore, early detection and treatment of these immune diseases is key to improving health outcomes.
“By developing a better understanding of the IKBKB gene and the role it plays in driving the onset of these diseases, it could bring us one step closer to one day finding a cure, which would offer new hope to hundreds of thousands of Australians.”
The research is published in Nature communications.
Source:
Journal Reference:
Cardinez, C., et al. (2024). IKK2 controls the inflammatory potential of tissue-resident regulatory T cells in a gain-of-function mouse model. Nature communications. doi.org/10.1038/s41467-024-45870-3.
