Intra-carotid arterial transfusion of autologous circulatory derived CD34+ cells for old ischemic stroke patients - a phase I clinical trial to evaluate safety and tolerability.

This phase I clinical trial tested the hypothesis that circulatory CD34+ cell therapy might be safe for old ischemic stroke (IS) (defined as IS>6 months) patients and also to evaluate the neurological function after the therapy. Nine old IS patients (with mean IS interval: 8.6 ± 6.4 years) were consecutively enrolled and received intra-carotid artery transfusion of circulatory-derived autologous CD34+ cells (3.0×107 cells/patient) into the ipsilateral brain infarct area at catheterization room by Catheter Looping Technique, after subcutaneous G-CSF injection (5 μg/kg twice a day for 4 days). The results showed that procedural safety was 100% with all patients uneventfully discharged. The circulating number of EPCs and angiogenesis (i.e., by Matrigel assay) were significantly higher at post than at prior to G-CSF treatment (all P<0.001). Time courses (0/5/10/30 minutes) of blood samplings from right-internal jugular vein exhibited significantly increased in levels of SDF-1α and EPCs numbers in time points of 5/10/30 minutes than in the baseline (0 minute) (all P<0.05). Barthel index was increased (defined as ≥5 scores) in 44.4% (4/9) and CASI score was notably improved (all P<0.01) at 6-month follow-up after the cell therapy as compared to the baseline. No recurrent IS or any tumorigenesis was found in these patients with a mean follow-up time interval of 16.5 ± 6.2 months. All of these patients remain survive and are followed up at outpatient department. In conclusion, CD34+ cell therapy is safe and might offer some benefit to old IS patients.