Antibodies used for immunostaining were SC101, a monoclonal antibody for human nuclei; SC121, a monoclonal antibody for human cytoplasm; and SC123, a monoclonal antibody specific for human GFAP (StemCells, Inc). Other primary antibodies included: b-tubulin III (Covance, Berkeley, CA); glutamate decarboxylase (GAD)-67, NeuN, NG2, and Neurofilament-150 (Chemicon); pan-GFAP (DAKO); Vimentin (Cell Marque, Hot Springs, AR); CC-1/APC (Oncogene); and myelin basic protein (MBP) 1-188 (Biogenesis, Bournemouth, U.K.). Secondary antibodies in double-labeling experiments were Alexa Fluor 488 and 555 from Molecular Probes.