Developing Novel Cell Sources for Transplantation in Parkinson's Disease.

Developing dopaminergic (DAergic) neurons that originate from aborted human embryos have been implanted into the brains of patients with Parkinson's disease (PD) and, in some cases, have successfully restored function. However, there are insufficient numbers of cells available to allow this therapy to become widely used. The limited amount of tissue from embryos may be circumvented by the use of cell lines that can be expanded in vitro for banking, then differentiated into DAergic neurons just prior to implantation into patients. Today, there are four main sources for such cell lines with future potential for banking and cell therapy for PD: human embryonic stem cells, human neural stem cells, human genetically immortalized stem/progenitor cells, and human adult-derived non-neural stem cells, such as bone marrow-derived stem cells. Currently, it is not possible to utilize these cell sources therapeutically for PD. The primary reasons are because it has not been feasible to effectively differentiate these cells into DAergic neurons and because the stability of phenotypic expression has been variable. This chapter describes methods to generate cells suitable for transplantation in PD in the future. The development of novel cell sources is described, along with an overview of the various types of stem cells that are suitable for grafting in PD. [ABSTRACT FROM AUTHOR]