Transplants of fetal neural tissue and autologous peripheral nerves in an attempt to repair spinal cord injuries in the adult rat. An overall view

Embryonic neurons and autologous peripheral nerve segments constitute selected materials for studying central nervous system plasticity and repair in adult mammals. Transplanted to the brain or the spinal cord, the former are possible substitutes designed to replace lost or deficient host neurons while the latter have useful stimulating and guiding effects upon axonal regrowth from surviving axotomized neurons. Consequently, these techniques give rise to interesting prospects for short and medium range fundamental research as well as for possible medium and long-term clinical applications. From a basic viewpoint, utilisation of such transplants is designed to study the survival, the morphological and biochemical differentiation, the reafferentation, the expression of potentialities for plasticity, axonal growth or regeneration, synaptogenesis, of host as well as of transplanted embryonic neurons. From a clinical viewpoint these studies should attempt at finding solutions to counteract the effects of severe traumatic or neurodegenerative lesions of the brain and of the spinal cord which until now appear quite refractory to therapeutic approaches.