Fig 2: Transplanted HUMSCs survived in the grafted-cerebellum and did not differentiate into neuronal cells. HUMSCs were labeled with the blue fluorescent nuclear staining bisbenzamide 48 h prior to transplantation and their viability and distribution were followed when the mice were sacrificed at 6 months of age. Blue fluorescent cell clusters were identified at lateral levels of bregma 1.2 mm, 2.1 mm, and 3.0 mm, with upper panel displaying the relative sites, lower panel showing the fluorescence photographs (a). Samples from six-month-old SCA1-HUMSCs mice were immunostained with antibody against human specific nuclei antigen (b). c RT-PCR was further applied to detect human NeuN and GFAP mRNA expressions in SCA1 mice. Human NeuN and GFAP mRNAs were not detectable in the SCA1-HUMSCs group. Human glioma cells were used as a positive control of human NeuN and GFAP mRNAs assay. d The expression of 174 human cytokines in mouse cerebella was examined 5 months after the HUMSCs transplantation. IL-13, GIF, PAI-1, FGF-2, and CXCL-4 were significantly increased in the group of SCA1-HUMSCs. * p < 0.05 compared with the Normal-PBS group. # p < 0.05 compared with SCA1-PBS

Fig 3: HUMSCs transplantation alleviated Purkinje cell damage SCA1 mice. Damages to the Purkinje cells in the SCA1 mice were assessed by sacrificing six-month-old SCA1 mice and observing, under optical microscope, Purkinje cells in lobules III and VI in tissue slices following immunohistochemical staining with anti-calbindin antibodies. Presented are representative photomicrographs of tissue slices of lobules III (a1 and a2) and VI (a3 and a4) in mice at 6 months of age in all groups. Purkinje cell number per unit length (b and d) and cell body area (c and e) in lobules III and VI were quantified. At 6 months of age, significant decreases were observed in both cell number and cell body area in the groups of SCA1 and SCA1-PBS. Transplantation of HUMSCs salvaged such losses (b-e). * p < 0.05 compared with the Normal group. ? p < 0.05 compared with the Normal-PBS group. # p < 0.05 compared with the SCA1-HUMSCs group

Fig 4: HUMSCs transplantation improved the amplitude of the compound motor action potentials in SCA1 mice. a Representative recordings of compound motor action potentials generated by the gastrocnemius muscles at 6 months of age for Normal, Normal-PBS, SCA1, SCA1-PBS, and SCA1-HUMSCs mice, showing markedly depressed action potentials in the SCA1 and SCA1-PBS groups and partial recovery by HUMSC transplantation. b Parameters of a schematic compound motor action potential assessed in the study. Quantifications of the mean amplitude, latency, and duration of the compound motor action potentials indicated, in the 6 months old SCA1 and SCA1-PBS mice, significant amplitude depressions which were partially recovered in the SCA1-HUMSCs group (c). However, no statistical differences were found among all the groups with respect to latency (d) and duration (e) recorded. * p < 0.05 compared with the Normal group. ? p < 0.05 compared with the Normal-PBS group. # p < 0.05 compared with the SCA1-HUMSCs group

Fig 5: HUMSCs transplantation alleviated molecular layer atrophy in six-month-old SCA1 mice. Six-month-old mice were sacrificed to examine alterations within cerebellar sagittal sections (a1). The areas of cerebellar sagittal section were quantified. HUMSCs transplantation reduced the shrinkage of cerebellum in SCA1 mice (b). All groups were examined, photomicrographs of entire sagittal sections were stained with Cresyl violet (a2-a6), lobule III at low (red arrow, a2 and a3) and high (a4) magnification, and lobule VI at low (blue arrow, a2 and a5) and high (a6) magnification were shown. In lobules III and VI, significant reductions were found in the molecular layer areas (c and d) and thickness (f and g) in the six-month-old SCA1 and SCA1-PBS groups. HUMSCs transplants could partially mitigate these reductions in SCA1-HUMSCs mice. There were no significant differences in the body weight among mice in all groups at the same ages (e). * p < 0.05 compared with the Normal group. ?p < 0.05 compared with the Normal-PBS group. # p < 0.05 compared with the SCA1-HUMSCs group