• Posted March 25, 2024

Mouse Study Yields Clues to Why Psoriasis Worsens

Australian researchers say they have identified a gene mutation that causes the skin disease psoriasis.

A chronic inflammatory condition, psoriasis causes red, scaly, itchy patches on the skin. Some patients also develop psoriatic arthritis, a condition marked by joint pain, swelling and stiffness.

But researchers at the Australian National University (ANU) who have identified the gene mutation hope their findings will point the way to a cure. In the short term, they hope the discovery will lead to improved diagnosis and treatment of both diseases, which they say can stigmatize patients.

"So many people are accused of having poor hygiene due to the plaques or even just minor skin lesions as they erupt," said Rebecca Davey, CEO of Arthritis ACT and one of at least 500,000 Australians with psoriasis. "It's not the individual's fault that their skin is in the condition it's in; psoriasis is a painful, debilitating condition."

But now there might be hope.

Researchers used a mouse model to identify a mutation in a gene known as IKBKB that causes a group of immune cells called regulatory T-cells to misfire. Patients with two copies of this gene are at increased risk for psoriatic arthritis, they report March 25 in the journal Nature Communications.

"These cells are normally considered gatekeepers of the immune system," said Chelisa Cardinez, a postdoctoral fellow at ANU in Canberra. "However, we found that this mutation alters the function of these cells, causing them to contribute to inflammation and promote the onset of disease."

Three out of 10 Australians with psoriasis develop psoriatic arthritis.

"Studies have shown that delays in psoriatic arthritis diagnosis is linked to worse outcomes for patients," Cardinez said in a university news release. 

"By developing a better understanding of the IKBKB gene and the role it plays in promoting the onset of these diseases, it could bring us a step closer to one day finding a cure," she added.

While there is no cure for psoriasis yet, treatments can help patients manage the condition. 

Davey, who also suffers from psoriatic arthritis, described her conditions as life-changing. When she gets up in the morning, she said the stiffness and pain she feels can be extreme.

"People don't understand the debilitating effects these conditions can have on the individual and, in fact, a whole family when someone is in constant pain, has poor sleep from pain and feels constantly fatigued," she said in an ANU news release. 

While medications have reduced larger skin outbreaks, Davey said she has to consider everything she puts on her skin and even what fabrics she can wear. 

"As a former nurse, even the constant hand washing that was required for work would cause my skin to flare up," she said. "It's one of the reasons why I no longer work in the hospital system."

Davey said it is important to raise awareness of "invisible disabilities" such as those created by these conditions.

"A person might look OK from the outside," she said, "but in reality they are struggling on a daily basis."

More information

There's more about psoriasis at the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

SOURCE: Australian National University, news release, March 24, 2024