Neuronal transplantation for motor stroke: from the laboratory to the clinic.

Laboratory studies have established the potential for neuronal transplantation to be of benefit to patients. Experimental studies in normal animals indicate that brain implantation of neurons seems safe. Implanted neurons integrated with the host brain, sent out axonal processes to communicate with other nerve cells, released transmitters (the chemical messengers of nerve cell communication), and demonstrated typical neuronal proteins. This article discusses phase I and II trials of neuronal transplantation in humans with small strokes in critical brain locations such as the basal ganglia region. More work is needed to confirm safety and to identify optimal measures of efficacy in this setting.