Abstract 11928: Patient-specific Induced Pluripotent Stem Cells For Modeling Hypoplastic Left Heart Syndrome
Background - Single ventricle (SV) defects including hypoplastic left heart syndrome (HLHS) is the most severe congenital heart malformations. The generation of patient-specific induced pluripotent stem (iPS) cells may offer a new strategy for disease modeling.
Methods and Results - Cardiac progenitor cells (CPCs) from 18 patients with congenital heart diseases were isolated and infected with retroviruses encoding human transcription factors, Oct4, Sox2, Klf4, and c-myc. Immunostaining, bisulfite sequencing, and global gene expression analysis were performed and established iPS cells were transplanted into NOD/SCID mice for teratoma formation. SV-derived CPCs had defective expression of Nkx2.5 and Hand1 but resulted in enhanced proliferative capacity compared with those from patients with bi-ventricle (BV) phenotypes. Patient-specific iPS colonies were found with higher reprogramming efficiency in SV-derived CPCs compared with those generated from BV hearts (77% vs 20%, n=18; p=0.026). Disease-specific iPS cells were uniformly expressed stringent pluripotent markers, Nanog, Oct4, TRA-1-60, TRA-1-81, SSEA-3/4, and alkaline phosphatase. Both types of CPCs showed similar patterns of intrinsic calcium oscillation. Although global gene analysis revealed that inductive signals essential for early cardiomorphogenesis, including BMP2, Sema3A, isl1, Bop1, Wnt3a, Tbx5, and Hand1/2, were significantly repressed in HLHS-derived CPCs, genes indispensable for mesoderm formation such as Notch1 and Foxh1 expressions increased remarkably compared with BV-derived CPCs. Upon cardiac differentiation, transcriptional factors Hand2, isl1, and Tbx5, contributing to primary and secondary heart-field morphogenesis, were markedly upregulated in BV-derived iPS cells, whereas GATA4 expression was enhanced in those generated from HLHS.
Conclusions - Our results suggest that patient-specific iPS cells provide an unprecedented research tool to study complex heart diseases that could not be physiologically reconstituted in animal models. HLHS-derived iPS cells have distinct cardiac differentiation program that may be applicable for disease investigation and development of novel regenerative medicine for congenital heart diseases.
- Hypoplastic left heart
- Regenerative medicine stem cells
- Single ventricle
- Congenital heart disease
- © 2012 by American Heart Association, Inc.