Umbilical Cord Mesenchymal Stem Cells Therapy (19#iSCLife®-SA) for Patients With Spinocerebellar Ataxia

Inclusion Criteria: * Clinical and genomic test diagnoses as spinocerebellar ataxias (SCA) (include SCA 1, SCA 2, SCA 3, SCA 6), SARA (Scale for Assessment and Rating of Ataxia) score is 2-5, can complete 8-meter walking test（8MW） * Do not receive stem cells treatment in 6 months * Participants sign the consent form based on the experiment process and statement Exclusion Criteria: * Cardiac, renal, hepatic insufficiency; total bilirubin is 1.5 times higher than normal value, aspartate transaminase（AST）or alanine aminotransferase（ALT）is 2.5 times higher than normal value * Hemogram: total white blood cells \<3.0 \* 10\^9 cells/L, blood platelet \<75 \* 10\^9/L, hemoglobin \<100g/L * pneumonia, or severe infection * With severe allergic history * Brain organic disorder, like brain tumor * Serum with HIV, syphilis antibody positive * Severe mental disease, cognitive disorder patients * Other severe system or organ organic disease * Pregnant, breast feeding, or planning pregnant women * Participate other clinical experiments in 3 months * With some other conditions that doctor propose not to participate