 Dysfunction of the immune system is a pathological hallmark of ALS. Increased levels of interferon gamma IFNgamma were found in the serum and cerebrospinal fluid CSF of ALS patients. However, the cell origin as well as the pathogenic influence of this peripheral source of IFNg is unknown. Thus, IFNgamma might have a role in the pathogenic process of ALS and might be a potential biomarker of the disease. 