Modeling Neurogenetic Disorders Via Induced Pluripotent Stem Cells – A Novel Alternative for Pathology.
Yunhua Bao, Anita J Huttner. Yale University School of Medicine, New Haven, CT
Background: Recent progress in our understanding of somatic cell reprogramming, particularly the isolation and characterization of human induced pluripotent stem cells (iPSCs) opened new avenues for modeling human disease. IPSCs allow the generation of large numbers of genetically modifiable cells specific to the underlying human genetic background, and form an unparalleled opportunity to gain new insight into disease pathophysiology. This will further lay the foundation for the development of patient specific pharmacological assays and/or stem cell based therapies. We focused on Walker Warburg Syndrome (WWS), a rare and severe form of congenital muscular dystrophy associated with lissencephaly. Most children die before the age of three years. Several genes have been implicated in the etiology of this syndrome, however, to this date the pathogenesis is poorly understood. In addition, none of the animal models appears to faithfully reflect the human condition. Patient derived IPSCs, however, allow the targeted differentiation of cells into tissue specific phenotypes of brain and muscle, and thus provide an assay for the recapitulation of disease specific pathophysiology.
Design: IPSC lines were derived from skin biopsy specimens of patients with WWS and normal age matched controls. We have achieved reprogramming of human fibroblasts using a lentiviral construct expressing human OCT4, SOX2, KLF4 and c-Myc/mCherry. The cells were grown in culture and differentiated into neurons, astrocytes and/or muscle. The in vivo potential of these progenitor cells was tested via in utero transplantation, which demonstrates the cells' ability to follow microenvironmental cues, migrate and differentiate appropriately.
Results: Directed differentiation of iPSCs into neuronal and myogenic precursors was demonstrated in vitro with antibodies for CNS phenotypes, like GFAP, TUJ1, Tbr1/2 as well as muscle phenotypes. The engraftment and integration of individual cells in vivo showed the ability of iPSCs to differentiate appropriately and show a disease specific difference to their normal counterpart.
Conclusions: This model allows the phenotypic recapitulation of complex neurogenetic traits, and provides insights into the pathophysiology of human forms of WWS.
Wednesday, March 2, 2011 9:30 AM
Poster Session V # 214, Wednesday Morning