GM-CSFR alpha is present on adult neural stem cells. A, B, GM-CSF receptor α is expressed on cells in the subgranular zone of the dentate gyrus, and in cells with extended processes in the granular cell layer that are reminiscent of migrating neural stem cells (A, 10× original magnification; B, 40× original magnification). C-E Hippocampal adult neural stem cells in culture also express the GM-CSF receptor α. The expression of the GM-CSF α receptor (C) colocalizes with the expression of the stem cell marker nestin (D) on an adult neural stem cell. E, merged image (all size bars 50 μm). F, RT-PCR demonstrates presence of the GM-CSF receptor on naive NSCs from the hippocampus (HC) and subventricular zone (SVZ) in vitro.