FOXP3 and amyotrophic lateral sclerosis: Notably, decreased numbers and activity of regulatory T cells (Tregs) and decreased forkhead box P3 (FoxP3) expression levels in peripheral lymphocytes have been suggested as biomarkers predicting rapid progression and attenuated survival in patients with ALS.14 Treg cells have been demonstrated to possess the capacity to induce the functional shifting of microglia toward the alternative, protective phenotype15-17 and suppress Type 1 T helper (Th1) lymphocyte proliferation.