TGFB1 and amyotrophic lateral sclerosis: Even if the increase in plasma TGFB1 levels has been confirmed also in mutSOD1 transgenic mice [49], whether TGFB1 plasma levels are biomarkers of ALS or not is still an open question; in fact, other studies fail to detect the changes of TGFB1 levels in patient CSF compared to healthy controls [50], or between fast and slow progressing ALS patients analyzed both at early and late stage of disease [49].