Ishikawa H, Tajiri N, Shinozuka K, Vasconcellos J, Kaneko Y, Lee HJ, et al. Vasculogenesis in Experimental Stroke After Human Cerebral EndothelialCell Transplantation. Stroke. 2013
Stem cell trials in stroke have primarily targeted clinical endpoints, but how does stem cell transplantation actually work on the molecular or histological level? The authors of this study have tested the hypothesis that direct vascular repair by endothelial cells contributes to neurogenesis/neuro-protection.
In the study, they transplanted cerebral endothelial cells called HEN6, of varying doses vs. placebo, into the striatum of rats with experimentally-induced MCA ischemic stroke. At 7 days, they found a dose-dependent relationship with higher HEN6 associated with smaller infarct volumes, and better functional outcome in terms of rat behavior. Histologically, they found less reactive gliosis (decreased GFAP staining) and more vasculogenesis (more collagen-IV staining). An in-vitro portion of the study also showed the positive effect of VEGF with HEN6 in reducing apoptosis compared to placebo.
This study supports the role of endothelial stem cells (HEN6) in vasculogenesis and better outcomes at 7 days post-stroke when transplantation occurs acutely. We have a stem cell study at our institution that is for stroke patients that are at least 6 months out from their stroke. Would the impact on functional recovery be similar at this time?