| Parkinson' s disease (PD) is the most common neurodegenerative disorder among the old people, which affects approximately 1% of the age of 50 years and seriously affects the health of individuals. Thereby, considering the growing number of the elderly, PD forming an increasing economic burden for society. Pathologically, PD experience a progressive loss of dopaminergic neurons within the sustantia nigra and a reduction of dopamine in the striatum. There is no effective treatment up to date. Though dopamine replacement therapy using the dopamine precursor, levodopa or dopamine receptor agonists can alleviate symptoms, they could not mitigate progression of the disease. Fetal brain transplantation is a new therapeutic strategy for PD. Several studies have shown that fetal dopaminergic transplants in animal models of PD ameliorated deficits induced by lesioning the dopaminergic nigrostriatal neurons. Clinical trials of human fetal transplantation as a therapy for PD have been attempted in several centers with encouraging results. However, widely spread application is severely limited by the moral and practical problems of obtaining sufficient donor tissue from human embryos, the long term therapeutic effect is inconsistent, and the rejection in host brain is also can not be neglected. Stem cell technique has gained great progress in recent years, it has been become the hot spot of biology and medical domain in the world. In recent years, therapid development of the study of NSC had open up a new path way for the therapy of central nervous system diseases.NSC transplantation is the hope to cure PD. Objective:part one:To investigate the conditions and methods about isolating and cultivating human embryo neural stem cells, on this base,to study the biology character of the NSC further.part two:To observe the improved degree of behaviours in monkey models of Parkinson' s disease after human embryo neural stem cells transplantation. To observe the pathological and immunocytochemical changes of transplanted zones in monkey' s brain.Methods:Part one : Isolating and cultivating human embryo CNS hippocampus neural stem cells by the technique of serum free cultivation combined with growth factor(EGF and bFGF).The hippocampus tissue was taken from the clinical aborted foetus (gestational age range from 8~16 weeks). After the NSC had grown into neurosphere, we passaged and freezed it. The mul tipotential of NSC was also be certified by immunocytochemistry method, the special antibodies matching neural stem cell (Nestin),neuron(NSE),astrocyte(GFAP) and ol igodendrocyte(GC) were applied to identify the primary n the passaged neural stem cells and the three cell types differented from NSC in vitro.Part two:l-methy-4-phenyl-l,2, 3, 6-tetrahydropyridine(MPTP) was used to prepare monkey models of hemi-Parkinson' s disease. Guided by neuronavigation system,human embryo CNS was transplanted into the PD mokey' s brain. The degree of behaviors in observed about monkeys is improved. Pathology proved the surviving of the transplanted NSC, immunocytochemistrytestified that the NSC differentiated to dopaminergic neuron.Results:part one: The results of immunocytochemistry showed:either the primary or the passaged neurosphere were nestin-positive, the results of immunocytochemistry the cells differentiated from them expressed NSE> GFAP and GC.Part two: After transplantation, the PD monkey' s motions low and muscle hypertonia was appparently improved. Limb tremor almost disappeared.Left spontaneous rotations behavior relieved.Rotating frequency caused became less than before transplantation.Through the immunoelectromicroscope,we observed that transplanted NSC was connected with the host brain cells in synapse.Conclusions:part one: We have established an effective method for culturing human embryo neural stem cells in vitro. The primary cultured and passaged human embryo NSC expressed Nestin and have the ability of self-renewing and multi-differentiation potential. The freezed NSC also have the ability of self-renewing and multi-differentiation potential.Part two: Human embryo NSC transplanted into the PD monkeys brain can establish synaptic connection with the host nervous cells and can differentiated to dopaminergic neuron.NSC transplantation is a effective method to treatment the PD.
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