[A century of neurotransplantation in mammals]

The transplantation of neural tissue into the mammalian brain has been studied for a century. Although the experimental foundations of neurotransplantation were limited to basic biological issues, the progress made over the last decade in the use of foetal neurotransplants to replace interrupted neuronal pathways or to correct induced functional deficit of the central nervous system (C.N.S.), has opened a new field of research for repair of the damaged C.N.S. This review summarizes three major topics: (1) the major developments in the field of neurotransplantation since the first attempt in 1890, (2) the global field of application of grafting techniques of autologous, homologous and heterologous transplants to particular neuroaxonal systems in animal models (sensory, endocrine, motor, cognitive systems), (3) the specific applications of neurotransplantation to experimental forms of human neurological disorders in rodents and non human primates as a potential treatment for neurodegenerative diseases, and the future directions of neural grafting techniques (in vitro and transgenic techniques, artificial substrates) in the context of the scientific and the ethical problems which have been recently addressed.