Abstract: Objective To observe the effectiveness of intrathecal injection with umbilical cord mesenchymal stem cells （UC-MSCs） in treating multiple system atrophy-cerebellar type （MSA-C）. Methods From December 2009 to April 2012, 40 patients with MSA-C were given UC-MSCs intrathecal injection with the dosage of 1 ×10^6 cells/Kg for once a week, 4 times as a course. Twenty-nine patients were treated with 1 course, 9 patients with 2 courses and 2 patients with 3 courses. International Cooperative Ataxia Rating Scale （ICARS） and Activity of Daily Living Scale （ADL） were used to evaluate patients＇ neural function and ability of daily living. Patients were followed up after treatment. Results In 53 courses, 47 courses are effective （the effective rate was 88.68%）. Compared with the ICARS and ADL scores before treatment, patients’ scores were significantly decreased 1 month after treatment （P〈0.01）. In most effective cases, clinical symptoms such as unstable walking and standing, slow movement, upper limb fine motor disorder, writing difficulties, dysarthria, eye movement disorders were improved. During treatment, common adverse effects were observed, as dizziness （4 cases）, low back pain （1 cases）, headache （2 case） and fever （2 cases）, all these symptoms disappeared within 1-3 days. No treatment-related adverse events were observed during 27-55 months （median 40 months） of follow-up. The stable effective period of patients ws 2-13 months （average 5.88±2.86 months）, then progressed. Conclusion UC-MSCs intrathecal injection is safe, and can ameliorate clinical symptoms to some extent. Multiple courses of treatment can further improve neurological function and delay illness progression in most patients.

Key words: Umbilical cord mesenchymal stem cells, Multiple system atrophy, Intrathecal injection