Investigators at the University of Alabama at Birmingham have identified the previously unknown role of a chemical "messenger" leading to autoimmune disorders, like rheumatoid arthritis and lupus.  The messenger is the naturally occurring chemical interleukin 17 (IL-17).

     The University of Alabama researchers pinpointed an unknown role that IL-17 plays in autoimmune and inflammatory responses, aside from its commonly known effects within immunity.  Future research will home in on IL-17's unwanted actions and preserve its benefits within the immune system.

     In the study, the scientists blocked messenger signals from the IL-17 protein to the immune system of mice.  This disruption significantly reduced the number of white blood cells, name disease-causing B cells clustered in the mice's spleen.  The number of B-cell clusters dropped from 17 percent to 2 percent when the IL-17 protein signals were blocked.  The drop was a clear sign that IL-17 plays a major role in shaping B cells' ability to create many more disease-causing antibodies.

     Many types of B cells make up the human immune system which is regulated to sense and fight infection without attacking normal, healthy tissue.  In autoimmune diseases, that regulatory process becomes imbalanced.

     "Knowing more about IL-17's ability to regulate unwanted B-cell migration will generate new ideas in the ongoing search for better drug targets in preventing and treating autoimmune disease," commented Hue-Chen Hsu, Ph.D., an assistant professor in the University of Alabama Birmingham Division of Clinical Immunology and Rheumatology, who is lead author on the study.

Source: University of Alabama at Birmingham, via Huliq, January 2, 2008