Safety and Efficacy of Umbilical Cord Mesenchymal Stem Cell Therapy for Patients With Hereditary Ataxia

Inclusion Criteria: * Aged 16-65 years. * Harding Diagnosis of SCAs, gene type confirmed. * Candidates who did not receive any stem cell therapy in past 6months. * sign the consent form and follow the clinic trail procedure. Exclusion Criteria: * Cardiac insufficiency; Renal insufficiency; hepatic insufficiency; Total bilirubin higher than 1.5 times of upper limit of normal value; AST /ALT higher than 2.5 times of upper limit of normal value； * Routine Blood Test: WBC count \<3.0×109/ L; PLT count \<5×109/L ; or Hemoglobin \<100g/L； * Combined Pneumonia or other Severe systemic bacteria infection； * Severe drug allergic history or anaphylaxis to 2 or more food or medicine； * Other brain organic disease (eg. Brain cancer)； * HIV+, Tumor Markers + ； * Severe psychotic patients, cognitive dysfunction， or can not understand or sign the Consent Form； * Other severe systemic or organic disease； * Uncontrolled hypertension，blood pressure≥180mmHg/110 mmHg after treatment； * Pregnancy； * Enrollment in other trials in the last 3 months； * Other criteria the investigator consider improper for inclusion.