Chapter 49 - Cell Therapy for Parkinson’s Disease

Abstract

Parkinson's disease (PD) is a neurodegenerative disease with the major pathology being the progressive loss of dopaminergic (DA) midbrain neurons in the substantia nigra. The cell loss is confined in space and neuronal subtypes, and this feature makes PD a suitable disease for cell-based therapies. In the past, fetal ventral mesencephalon (fVM) tissues have been tested in clinical trials. Although in some cases significant efficacy was observed, fVM transplantation involves issues such as immune recognition, heterogeneity of grafts, lack of standardization, and uneven distribution of grafts, etc. The rapidly advancing field of reprogramming may offer cell sources to solve some problems associated with fVM transplants. Induced pluripotent stem cells and induced neural stem cells hold promise for generating clinical grade DA neural cells that are safe, homogeneous, scalable, and standardizable. Before these new cell sources are tested in clinical trials, the safety and efficacy need to be examined in PD animal models. In this chapter, I will also summarize small and large animal models of PD, which can be categorized into toxin-induced and genetically modified models, each with its merits and weaknesses. These models have been useful in providing a better understanding of PD mechanisms and facilitated the development of new therapies for PD treatment.