Parkinson's disease (PD) is the second most common neurodegenerative disorder in which the main pathology is selective degeneration of midbrain dopaminergic (mDA) neurons in the substantia nigra. Because of this specific cell loss, PD is considered to be a prime target disease for cell-based therapy. Indeed, numerous clinical and preclinical studies demonstrated the proof-of-principle that cell transplantation is a viable therapeutic regimen for PD treatment once an ideal and unlimited cell source can be established (reviewed in (Redmond, 2002;Li et al., 2008a;Lindvall and Kokaia, 2009). In 2006, Shinya Yamanaka and his colleagues published their groundbreaking work showing that pluripotent stem cells, so called "induced pluripotent stem cells (iPSCs)", can be generated from somatic cells by retroviral transduction of four reprogramming factors (i.e., Oct4, Sox2, Klf4 and c-Myc)(Takahashi and Yamanaka, 2006). Subsequent successful generation of human iPSCs by similar methods (Takahashi et al., 2007;Yu et al., 2007;Park et al., 2008a) offered the possibility to generate disease- or patient-specific stem cells without destruction of embryos. Indeed, these iPSCs offer unprecedented potentials for biomedical research, disease mechanism study, and personalized cell-based therapies. However, current iPSCs suffer from major drawbacks including multiple viral integrations and remaining transgenes at various chromosomal locations, any of which may cause unpredictable genetic dysfunction and/or tumor formation, making these cells unsuitable for clinical applications (Yamanaka, 2009a). With the long-term goal of developing a personalized cell-based therapy of PD using iPSCs, we propose the following three specific aims. First, based on our preliminary results (Kim et al., 2009a), we will establish iPSC lines from healthy and sporadic PD subjects by a novel, DNA-free reprogramming method (i.e., direct delivery of reprogramming proteins). We will extensively evaluate morphological, gene expression, epigenetic, and in vitro and in vivo differentiation properties to establish iPSC lines exhibiting properties similar to human embryonic stem cells (hESCs). We will compare their properties with those of hESC lines and iPSCs generated by conventional retroviral methods. In addtion, we will investigate their chromosomal integrity by state of the art copy number variation analysis. Second, once authentic iPSC lines are established, we will fully characterize and compare their in vitro differentiation properties into neural progenitors and midbrain DA neurons. We will optimize their differentiation into A9 DA neurons and evaluate the molecular, cellular, and electrophysiological characters of DA neurons from these iPS cells. Third, we will initiate to evaluate the potential functional benefits of these iPSC-derived DA neurons in two rodent models of PD;aphakia mice and 6-OHDA lesioned rats, both of which are well established in our laboratory. Biological and behavioral outcomes of these transplantation studies will be systematically investigated. Overall, our proposed experiments will provide invaluable insights and stepping stones, leading to the development of safe, realistic, and ideal cell source for personalized cell-based therapy of PD.
Although in its infant stage, the induced pluripotent stem cell (iPSC) technology is a tantalizing new method that can revolutionize biomedical research, disease mechanism studies, and customized cell-based therapies. To explore the potential of iPSCs for personalized cell-based therapy for PD, we propose to establish and characterize clinically viable iPSC lines from healthy and sporadic PD subjects by direct delivery of reprogramming proteins without any virus or DNA vectors. This proposal will provide important stepping-stones for realistic development of a personalized cell-based therapy of PD using DNA- or transgene-free iPSCs, which could be applicable to many other human diseases.
|Moon, Minho; Jeong, Inhye; Kim, Chun-Hyung et al. (2015) Correlation between orphan nuclear receptor Nurr1 expression and amyloid deposition in 5XFAD mice, an animal model of Alzheimer's disease. J Neurochem 132:254-62|
|Chung, Sangmi; Moon, Jisook; Kim, Kwang-Soo (2014) Improvement of neurological dysfunctions in aphakia mice, a model of Parkinson's disease, after transplantation of ES cell-derived dopaminergic neuronal precursors. Methods Mol Biol 1213:285-91|
|Kim, Tae-Gon; Yao, Ruiqin; Monnell, Travis et al. (2014) Efficient specification of interneurons from human pluripotent stem cells by dorsoventral and rostrocaudal modulation. Stem Cells 32:1789-804|
|Park, Hansoo; Kim, Dohoon; Kim, Chun-Hyung et al. (2014) Increased genomic integrity of an improved protein-based mouse induced pluripotent stem cell method compared with current viral-induced strategies. Stem Cells Transl Med 3:599-609|
|Kim, Kyoung-Shim; Kang, Young-Mi; Kang, Young et al. (2014) Pitx3 deficient mice as a genetic animal model of co-morbid depressive disorder and parkinsonism. Brain Res 1552:72-81|
|Hong, Sunghoi; Chung, Sangmi; Leung, Kaka et al. (2014) Functional roles of Nurr1, Pitx3, and Lmx1a in neurogenesis and phenotype specification of dopamine neurons during in vitro differentiation of embryonic stem cells. Stem Cells Dev 23:477-87|
|Lee, Mi-Ok; Moon, Sung Hwan; Jeong, Ho-Chang et al. (2013) Inhibition of pluripotent stem cell-derived teratoma formation by small molecules. Proc Natl Acad Sci U S A 110:E3281-90|
|Park, Kyung-Soon; Cha, Young; Kim, Chun-Hyung et al. (2013) Transcription elongation factor Tcea3 regulates the pluripotent differentiation potential of mouse embryonic stem cells via the Lefty1-Nodal-Smad2 pathway. Stem Cells 31:282-92|
|Chung, Sangmi; Moon, Jung-Il; Leung, Amanda et al. (2011) ES cell-derived renewable and functional midbrain dopaminergic progenitors. Proc Natl Acad Sci U S A 108:9703-8|
|Rhee, Yong-Hee; Ko, Ji-Yun; Chang, Mi-Yoon et al. (2011) Protein-based human iPS cells efficiently generate functional dopamine neurons and can treat a rat model of Parkinson disease. J Clin Invest 121:2326-35|