Transplantation of neuronal progenitor or “stem cells” offers great promise for developing an epilepsy cure. Because transplanted progenitors can migrate and integrate as new neurons in the host brain, manipulation of these cells could be a powerful means to stop seizures before they start. Dr. Baraban’s lab has developed a method to transplant embryonic progenitor cells that integrate exclusively as inhibitory interneurons. In a parallel study, they developed a mouse mutant characterized by interneuron loss, reduced inhibition and late-onset epilepsy. Combining the expertise of Dr. Baraban, an established epilepsy investigator and Dr. Rubenstein, a world-expert on interneuron development, this CURE study will combine these two projects into a critical “proof-of-principle” trial aiming to determine whether transplanted GABA-progenitor cells restore normal levels of inhibition and rescue these mutant mice from developing epilepsy. This study is a necessary next step toward development of appropriate clinical treatments utilizing progenitor cells.