One of the most important questions surrounding a pervasive autoimmune disease may have finally been answered.
Research from the Northwestern Medicine and Brigham and Women’s Hospital may have finally found the root cause of a potentially fatal autoimmune condition that affects over one million people in the United States.
Long-Held Beliefs Challenged
The prevailing belief among scientists has been that genetics/hormones make some people predisposed to having lupus – with various environmental factors acting as a trigger.
The study published on Wednesday in the journal Nature suggests the disease’s development can be linked to immune system abnormalities
Study Details on Lupus Findings
Dr. Deepak Rao, one of the study authors and a rheumatologist, said, “What we found was this fundamental imbalance in the types of T cells that patients with lupus make.”
T-cells are white blood cells that play an important role in the immune response. The study found that people with lupus had “too much of a particular T cell associated with damage in healthy cells and too little of another T cell associated with repair.”
Excess Interferon Linked to Lupus
At the core of the imbalance is the protein interferon. Scientists have long known that lupus sufferers have an excess amount of type I interferon. However, they were not previously aware of the extent of negative effects this causes.
Too much type I interferon can block a protein called the aryl hydrocarbon receptor, which is essential in regulating bodily responses to bacteria and pollutants.
T Cell Production Issues in Lupus
Researchers found that blocking the aryl hydrocarbon receptor led to the production of T cells involved in making autoantibodies that attack healthy cells. They also found that it hindered the production of good T Cells which help heal wounds.
Rao said the theory could offer an explanation for most lupus cases, declaring, “I think this is going to apply to essentially all patients with lupus.”
Experts Question Single Lupus Explanation
Not all experts agree that there is a singular explanation for all cases of lupus. “It’s very exciting research and very hopeful, but I think that it might be too early to say that it’s the root cause of the disease,” said Mara Lennard Richard of the Lupus Research Alliance.
“It’s been very hard to find one singular root cause for the disease,” Lennard Richard said. “Obviously, if this turns out to be the cause of lupus, that would be amazing and really fantastic for people living with lupus.”
Need for Further Research
The new theory would need to be tested via a larger sample said Dr Jill Buyon, director of the division of rheumatology and the Lupus Center at NYU Langone Health.
Buyon said, “Until they study 100 patients prospectively, how are we going to know?”
Lupus Affects Millions in the US
The Centers for Disease Control and Prevention (CDC) says a little over 200,000 people in the United States have lupus, with 90% of sufferers being women.
However, the Lupus Foundation of America believes the number of Americans suffering from the condition is much higher – putting their estimates at approximately 1.5 million people.
Common Lupus Symptoms
Symptoms of lupus include joint pain, skin rashes and fatigue. In the most extreme cases, potentially fatal kidney and heart damage can occur.
Many of the current options used to treat lupus suppress the immune system, including beneficial T cells. For some, none of the standard treatments are effective.
Next Steps in Lupus Treatment
The new study found that giving lupus sufferers anifrolumab, a drug that blocks interferon, prevented the T-cell imbalance linked to the disease.
Blood samples of lupus sufferers found that adding a small molecule that activates the aryl hydrocarbon receptor limited the accumulation of disease-promoting T cells. However, while these results are promising, potential side effects remain of concern and there is unlikely to be a one-size-fits-all treatment.
