A sugar produced by soil bacteria may be able to stop the loss of skin pigment caused by vitiligo.
Injecting the molecule into mice with the autoimmune disease slowed the rate of the rodents’ pigment loss and boosted the amount of pigment-protecting T cells, according to a new study.
The research was led by dermatologist Caroline Le Poole, Ph.D., of Northwestern University’s Feinberg School of Medicine. The results were published in the Journal of Investigative Dermatology last month and shared in a Jan. 28 press release.
The sugar is an exopolysaccharide (EPS) made and secreted by Bacillus subtilis, a harmless bacterium that thrives in soil.
“Our next step is collaborating with scientists from several institutions to refine the compound, understand its mechanisms and determine whether it works alongside existing treatments for autoimmune disease,” Le Poole said in the release.
Mice with vitiligo given weekly injections of the EPS into their abdomens had 74% less depigmented skin on their backs after 18 weeks compared to untreated mice. Their skin also had fewer killer T cells, the cells responsible for destroying pigment, and more regulatory T cells, which protect against killer T cells, according to the study.
Vitiligo occurs when the immune system turns on melanocytes, the cells responsible for making the dark pigment melanin. Though the disease can affect anyone, its characteristic white skin patches are more obvious on people with darker skin—a fact that subjects those patients to significant social stigma.
The disease also commonly occurs alongside another autoimmune condition, according to the release, and is associated with an increased risk for cardiovascular disease, psychological distress and endocrine disorders.
There is no cure for vitiligo, but the FDA approved the first re-pigmentation drug for the disease in 2022, Incyte’s Opzelura. In clinical trials of the drug, just 30% of patients regained 75% or more of their face pigmentation, according to the Northwestern University release.
“Our findings about the effectiveness of microbial therapy could give hope to patients who are not well-served by existing treatments,” Le Poole said.