الفهرس 
Introduction
Fetal stem cellsOnly 14 pages are availabe for public view
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Abstract
Stem cells are basic cells of all multicellular organisms. Stem cells retain the ability to renew themselves through cell division and can be differentiated into a wide range of specialized cell types. Stem cell therapy plays an important role in the replacement of lost tissue.
Parkinson’s disease is a progressive neurodegenerative movement disorder, characterized by a continuous and selective loss of dopaminergic neurons in the midbrain. Cell based therapy has been employed to overcome limitations of conventional symptomatic treatment. The cell based therapy includes: a. Induction of proliferation and dopaminergic differentiation of endogenous stem cells, or b. Replacement of the lost cells by transplantation of either developing neural tissue or stem cells into the degenerated host brain.
Various types of stem cells can be used; embryonic stem cells, induced pluripotent stem cells, fetal neural stem cells, adult neural stem cells and non neural adult stem cells.
Conclusion
• The controlled production of dopaminergic cells in large amounts for cell replacement (neurotransplantation) in PD is technically possible.
• The adult brain tissue shows a regenerative potential.
• Embryonic stem cells might have a great potential for cell replacement strategies in PD, either concerning their proliferative or their differentiation capacity.
• The proliferation potential as well as the differentiation capacity of neural stem cells are however limited compared to that of embryonic stem cells, but these cells showed significant histological and behavioral improvement in PD models.
• The use of fetal tissue-derived neural stem cells seems to be the safest and most likely the fastest way to establish a transplantation protocol in PD.
• Non neural adult stem cells and induced pluripotent stem cells provide a possibility of autologous transplantation.
• Future studies are needed to determine the exact molecular mechanisms which control the in vivo neurogenesis and dopaminergic differentiation.