Immune responses are controlled by specialized cells known as dendritic cells. Dr. Carla Rothlin and colleagues at Yale University found that a protein called protein-S acts as a signal to turn off dendritic cells and thereby calm down the immune system.
“Previously protein S was thought only to play a role in blood clotting,” said Dr. Rothlin. “We have discovered that it also keeps the activation of dendritic cells in check and might prevent the possibility of developing autoimmunity.”
Protein S is known to be low in lupus patients and Dr. Rothlin plans to study if this is due to genetic defects. If so, restoring protein S function could be a new strategy to treat lupus.
The results are published in the July 25 issue of the leading biomedical journal Immunity. These findings could lead to more effective therapies for many diseases caused by out-of-control immune responses, including autoimmune disorders like lupus and inflammatory bowel diseases, and allergies.