Immunohistochemical analysis showed that MSC treatment with a ×0.2 or ×2 of the standard dose in MSA animals led to a significant increment of TH‐positive and DARPP‐32‐positive neurons in the SN and striatum compared with MSA animals receiving placebo (Fig. 4A, 4B). The gene discussed is PPP1R1B; the disease is multiple system atrophy.