Proliferation of clonally expanded, adult spinal cord stem-like cells after transplantation. Immunofluorescence of BrdU (red) is combined with labeling for the proliferation marker Ki-67 (green). A, Coronal view of the adult rat hippocampus showing the presence of some proliferating cells in the subgranular zone, GCL, and hilus. Theboxed area is shown at a higher magnification inB. B, A cluster of proliferating cells in the subgranular zone (arrowhead) adjacent to a BrdU-labeled cell (arrow) in the GCL.