CD4 and amyotrophic lateral sclerosis: As HGF/SF has been reported to exert immunosuppressive properties on both CD4+ and CD8+ T cells in a mouse model of multiple sclerosis [26,27] and growing evidence suggest a role of the adaptive immune system in the pathogenesis and progression of ALS [10,24], we investigated the effect of K1K1 treatment on this mechanism in our ALS model.