Blocking Immune System IL1 Helps Mice With MG

Erdem Tuzun and Premkumar Christadoss, both MDA-funded investigators at the University of Texas Medical Branch in Galveston, were part of a group that recently demonstrated the potential value of blocking the action of interleukin 1 (IL1) in treating myasthenia gravis (MG).

In most cases of MG, the patient’s immune system mistakenly attacks the part of each muscle cell that receives signals from the nervous system -- the acetylcholine receptor. IL1 and several other substances associated with the immune system combine to destroy or block acetylcholine receptors, causing the fluctuating weakness of MG.

The researchers, who published their report in the Aug. 1 issue of the Journal of Immunology, gave multiple daily injections of an IL1-blocking compound for two weeks to mice destined to develop a laboratory-induced form of MG. (The mice had been immunized against their own acetylcholine receptors.)

The injections reduced the number of cases of MG that developed in the mice and, in those cases that did develop, the symptoms were less severe than in the mice that didn’t receive the IL1 blocker.

The authors say that compounds that block IL1 activity, perhaps in combination with etanercept, which blocks the activity of another immune-system compound, might be beneficial in the treatment of human MG. Because current treatments for MG often involve the use of highly toxic medications, the search is on for better strategies.