New findings on autoimmune diseases

ScienceDaily (Oct. 11, 2010) — Adeficiency in one of the immune system's enzymes affects the severityof autoimmune diseases such as MS, and explains why the course of thesediseases can vary so much. New findings give an insight into how thisenzyme deficiency can be diagnosed, and could lead to new medicines,reveals a thesis from the Sahlgrenska Academy.
Multiple sclerosis (MS) and Guillain-Barré syndrome (GBS) -- the twoautoimmune diseases covered by the thesis -- can follow vastly differentcourses, with symptoms ranging from insignificant to life-threatening,the reason for which has been largely unknown. In the thesis theresearchers have now found a factor in the immune defence that canexplain this mechanism.
The immune system's white blood cells play an important role in thefight against invading micro-organisms. They contain an enzyme calledNADPH oxidase, which converts oxygen into reactive oxygen radicals. Ithas long been known that these oxygen radicals stop infections bybreaking down micro-organisms. New studies using animal models haveshown that inadequate production of oxygen radicals can lead to thedevelopment of autoimmune diseases, where a patient's immune systemattacks the body's own tissues. This would indicate that oxygen radicalsare important for preventing the occurrence of autoimmune diseases.
"We wanted to look at this in humans, and examined the NADPH oxidasein the white blood cells of patients with MS, GBS and recurring GBS(RGBS)," says Natalia Mossberg, doctoral student at the Institute ofNeuroscience and Physiology at the Sahlgrenska Academy. "The resultsshow that patients with more severe forms of the illness have lowerlevels of oxygen radical production in their white blood cells as aresult of deficient NADPH oxidase function."
The researchers discovered that the body's ability to producereactive oxygen radicals at an early stage in the immune defence againstinfections has a major impact on how these illnesses develop. "We'veshown that a strong but controlled production of oxygen radicals by theimmune system is important for subduing illnesses such as MS and GBS,"says Mossberg.
The researchers think that this method of measuring oxygen radicalproduction in white blood cells can be used for investigating otherautoimmune diseases and for diagnosing the severity of these illnesses.The discovery could also lead to a new approach to the treatment of MSin its early stages with medicines that trigger the production of NADPHoxidase or a vaccination for people at risk of developing this type ofillness.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.