Immune System Safety Mechanism Discovered in Autoimmune Disease

Discovery may help regulate B lymphocytes and lead to new treatments for systemic lupus erythematosus.

An unknown mechanism in the immune system helps keep autoimmune diseases from attacking our bodies.

In a recent study, researchers discovered a safety mechanism in the immune system that prevents autoimmune disease, and appears to be lacking in patients with systemic lupus erythematosus (SLE).

B lymphocytes are one of the main causal factors of numerous autoimmune diseases, including SLE. When they start reacting to the body’s native structures, it gives rise to the symptoms of the condition.

“Our research group has been interested in B lymphocytes and what goes wrong in the regulation of different types of autoimmune disease,” said researcher Mikael Karlsson, whose study was published in Nature Immunology.

Although it was previously established that the neutrophil cell plays an important role in wound healing, as well as the early stages of immune response, new findings reveal they have another crucial function in their interaction with B lymphocytes.

“We have discovered a previously unknown mechanism in the immune system that prevents autoimmune disease and that could be lacking, we think, in people with autoimmune diseases such as SLE,” Karlsson said.

Typically, when inflammation occurs, the neutrophils cause B lymphocytes in the spleen to begin producing antibodies that slow an infection. However, researchers discovered that the neutrophils also communicate with an NKT cell, and orders it to regulate the response in order to avoid overreaction.

Since SLE patients have few NKT cells compared with other people, the findings suggest that this could be a contributing factor of the body failing to regulate B lymphocytes.

“Apart from our discovery being interesting in general terms of how the immune system works, it can also be very important for people with other autoimmune diseases,” Karlsson said. “We think that this mechanism could be used to regulate B lymphocytes in different morbid conditions and that it could be a way forward for stopping SLE.”