EN
The use of stem cells has been proven an attractive strategy for restoring lost cell or tissue functions. Stem cell therapy is nowadays routinely used in many clinical applications. The complexity of the tissue in the central nervous system however often limits the use of stem cells yet to reconstructions of defi ned wellknown neurotransmitter defi cits, for example the reconstitution of the nigro-striatal system in Parkinsonís disease (PD). However, the selective loss of a specifi c type of dopaminergic cells in PD makes the prospect of replacing the missing or damaged cells very attractive. Indeed, fi rst controlled clinical trials of intrastriatal transplantation of primary dopaminergic tissue in PD provide the ìproof-of-principleî of cell replacement strategies in PD. On the other hand, those trials also demonstrated several scientic limitations. Recent developments in stem cell research however provide new cell types for cell replacement strategies in PD. Furthermore, the ongoing developments during the recent years showed alternative applications of stem cells in neurological diseases such as the use of neural stem cells as neuroprotective agents or as vectors for transferring genes of interest. Due to the discovery of neural stem cell also in the adult brain, the questions concerning their role in physiological and pathophysiological conditions as well as their potential for endogenous regeneration has to be further investigated. Cultivating and characterizing these cells aims to understand mechanisms of neuronal degeneration and regeneration and could help to develop therapeutic strategies, as for example the stimulation of endogenous stem cells by pharmacological compounds. In this presentation, the different strategies for the use of stem cells to treat PD will be summarized and discussed.