Stroke induces ependymal cell transformation into radial glia in the subventricular zone of the adult rodent brain.

Adult ependymal cells are postmitotic and highly differentiated. Radial glial cells are neurogenic precursors. Here, we show that stroke acutely stimulated adult ependymal cell proliferation, and dividing ependymal cells of the lateral ventricle had genotype, phenotype, and morphology of radial glial cells in the rat. The majority of radial glial cells exhibited symmetrical division about the cell cleavage plane, and a radial fiber was maintained throughout each stage of cell mitosis. Increases of radial glial cells parallel expansion of neural progenitors in the subventricular zone (SVZ). Furthermore, after stroke radial glial cells derived from the SVZ supported neuron migration. These results indicate that adult ependymal cells divide and transform into radial glial cells after stroke, which could function as neural progenitor cells to generate new neurons and act as scaffolds to support neuroblast migration towards the ischemic boundary region.