Great news for psoriasis sufferers! Scientists at Washington University School of Medicine in St. Louis have isolated a compound from the body’s immune system that eliminated psoriasis in mice. This revolutionary treatment offers hope of a cure, and even has the potential to treat other autoimmune diseases.
What is psoriasis?
Psoriasis is an autoimmune disorder in which the immune system triggers inflammation in the skin. It causes elevated, itchy patches of skin, most often on the elbows, knees, and scalp. Raised red skin covered with thick, silvery scales is psoriasis’s trademark rash. There’s a genetic component to psoriasis, and it often presents together with other autoimmune diseases. While there are many topical and systemic treatments available, none of them cure the underlying condition.
Like all autoimmune diseases, inflammation is a major component in psoriasis. A key driver in the autoimmune response is an inflammatory pathway called IL-17. This pathway helps the immune system fight off certain infections, but it also has a dark side. When triggered, IL-17 facilitates tissue destruction in psoriasis, multiple sclerosis (MS), and rheumatoid arthritis.
Beating the immune system at its own game
How does the immune system work? When the body detects an infection, a powerful army of cells and molecules mobilize at the site. This causes inflammation as the immune system works to eradicate the pathogen. Autoimmune disorders happen when the immune system, in response to unknown triggers, turns the inflammation on the body’s healthy tissue.
A previous study by the same researchers found that when certain immune system cells—called macrophages—detect bacteria, they produce great amounts of the compound itaconate. The itaconate takes on an anti-inflammatory effect. In that study, the scientists used a version of itaconate, called dimethyl itaconate, to treat macrophages from both mice and humans. The results showed that dimethyl itaconate inhibits IL-17’s inflammatory action. Since there is a probable link between IL-17 and psoriasis, the researchers hypothesized that the new compound could treat the disease.
To test their hypothesis, they induced psoriasis in the ears of a group of mice. They then gave half the mice dimethyl itaconate every day. The other half was the control group, and those mice only received placebos. After a week, the treated rodents looked completely normal, while the control group’s ears just got worse.
“We are taking advantage of the body’s own anti-inflammatory power and showing that it can help in real situations when your own immune system is hurting you,” said Dr. Maxim Artyomov, the lead researcher in the study. He continued, “Now we know that itaconate compounds can help with autoimmune diseases, specifically in psoriasis and potentially in multiple sclerosis. This small molecule is turning out to be really powerful.”