Adult bone marrow transplantation after stroke in adult rats.

We transplanted adult whole bone marrow prelabeled with bromodeoxyuridine (BrdU) into the ischemic boundary zone of the adult rat brain at 1 day after 2 h of middle cerebral artery occlusion (MCAo). Approximately 3.3% of 10(6) transplanted bone marrow cells were BrdU reactive at 14 days after MCAo. BrdU-reactive cells expressed neuronal and astrocytic proteins, neuronal nuclei protein (NeuN, 1%), and glial fibrillary acidic protein (GFAP, 5%) immunoreactivities, respectively. In addition, bone marrow transplantation promoted proliferation of ependymal and subependymal cells, identified by nestin (a neuroepithelial stem cell marker), within the ventricular zone and subventricular zone (VZ/SVZ). These data suggest that intracerebral transplantation of bone marrow could potentially be used to induce plasticity in ischemic brain.