Successful survival of grafted transgenic neural plate cells in adult central nervous system environment.

1. Accumulating evidence indicates that damaged brain functions can be ameliorated in a variety of animal models by the grafting of fetal neuronal cell or tissue into damaged brain. Clinical trials are under way to determine whether human fetal mesencephalic tissue can ameliorate motor functions in patients with Parkinson's disease. 2. Autopsy findings of parkinsonian patient implanted with human fetal mesencephalic tissue clearly revealed that the fetal neuronal graft can survive for an extended period of time in the human brain and densely reinnervate the surrounding host striatal tissue. 3. It is, however, still important to obtain more practical, effective, and ethically justifiable donor material for the future clinical application of the procedures. Desirable properties for the donor cells include long-term survival in the brain, neuronal cell type for the reconstruction of damaged neural circuits, and susceptibility to genetic manipulation for the practical use. 4. With the development of molecular biology techniques, genetic modification and transplantation of the donor neuronal cells might be a feasible way to cure many kinds of central nervous system diseases toward a "graft-gene therapy."