Rat Embryonic Fibroblasts Improve Reprogramming of Human Keratinocytes into Induced Pluripotent Stem Cells

2012 ◽  
Vol 21 (6) ◽  
pp. 965-976 ◽  
Author(s):  
Leonhard Linta ◽  
Marianne Stockmann ◽  
Karin N. Kleinhans ◽  
Anja Böckers ◽  
Alexander Storch ◽  
...  
2013 ◽  
Vol 33 (22) ◽  
pp. 4434-4447 ◽  
Author(s):  
Takashi Yugawa ◽  
Koichiro Nishino ◽  
Shin-ichi Ohno ◽  
Tomomi Nakahara ◽  
Masatoshi Fujita ◽  
...  

NOTCH plays essential roles in cell fate specification during embryonic development and in adult tissue maintenance. In keratinocytes, it is a key inducer of differentiation. ROCK, an effector of the small GTPase Rho, is also implicated in keratinocyte differentiation, and its inhibition efficiently potentiates immortalization of human keratinocytes and greatly improves survival of dissociated human pluripotent stem cells. However, the molecular basis for ROCK activation is not fully established in these contexts. Here we provide evidence that intracellular forms of NOTCH1 trigger the immediate activation of ROCK1 independent of its transcriptional activity, promoting differentiation and resulting in decreased clonogenicity of normal human keratinocytes. Knockdown of NOTCH1 abrogated ROCK1 activation and conferred sustained clonogenicity upon differentiation stimuli. Treatment with a ROCK inhibitor, Y-27632, or ROCK1 silencing substantially rescued the growth defect induced by activated NOTCH1. Furthermore, we revealed that impaired self-renewal of human induced pluripotent stem cells upon dissociation is, at least in part, attributable to NOTCH-dependent ROCK activation. Thus, the present study unveils a novel NOTCH-ROCK pathway critical for cellular differentiation and loss of self-renewal capacity in a subset of immature cells.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 425
Author(s):  
Xia Yuan ◽  
Chen Zhang ◽  
Ruifeng Zhao ◽  
Jingyi Jiang ◽  
Xiang Shi ◽  
...  

Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) in vitro. Previously, a lentivirus induction strategy of introducing Oct4, Sox2, Nanog and Lin28 (OSNL) into the iPSC process has been shown as a possible way to produce chicken iPSCs from chicken embryonic fibroblasts, but the induction efficiency of this method was found to be significantly limiting. In order to help resolve this efficiency obstacle, this study seeks to clarify the associated regulation mechanisms and optimizes the reprogramming strategy of chicken iPSCs. This study showed that glycolysis and the expression of glycolysis-related genes correlate with a more efficient reprogramming process. At the same time, the transcription factors Oct4, Sox2 and Nanog were found to activate the expression of glycolysis-related genes. In addition, we introduced two small-molecule inhibitors (2i-SP) as a “glycolysis activator” together with the OSNL cocktail, and found that this significantly improved the induction efficiency of the iPSC process. As such, the study identifies direct molecular connections between core pluripotency factors and glycolysis during the chicken iPSC induction process and, with its results, provides a theoretical basis and technical support for chicken somatic reprogramming.


2017 ◽  
Vol 4 (S) ◽  
pp. 96
Author(s):  
Oanh Thuy Huynh ◽  
Mai Thi-Hoang Truong ◽  
Phuc Van Pham

Background: Embryonic stem cells are pluripotent, thus capable of differentiating into all types of cells derived from the three germ layers. However, the application of embryonic stem cells (ESCs) for preclinical and clinical studies is difficult due to ethical concerns. Induced pluripotent stem cells (iPSCs) are derived from differentiation and have many ESC characteristics. The study herein examines the production of iPSCs from reprogramming of mouse embryonic fibroblasts (MEFs) via transduction with defined factors.  Methods: MEFs were collected from mouse embryos via a previously published protocol. The cells were transduced with a single polycistronic viral vector encoding mouse cDNAs of Oct3/4, Sox2, Klf4 and c-Myc. Transduced cells were treated and sub- cultured with ESC medium. The cells were evaluated as iPSCs with specific morphology, and expression SSEA-1, Oct3/4, Sox2 and Nanog. In addition, they were also evaluated for pluripotency by assessing alkaline phosphatase (AP) activity and in vivo teratoma formation.  Results: Under the reprogrammed conditions, the transduced cells displayed a change in morphology, forming ESC-like clusters. These cell clusters strongly expressed pluripotent markers as well as ESC-specific genes. Furthermore, the colonies exhibited higher AP activity and formed teratomas when injected into the murine testis.  Conclusion: The study herein suggests that MEFs can be reprogrammed into iPSCs using a polycistronic viral vector encoding mouse cDNAs for Oct3/4, Sox2, Klf4 and c- Myc


2017 ◽  
Vol 4 (01) ◽  
pp. 159 ◽  
Author(s):  
Oanh Thuy Huynh ◽  
Mai Thi-Hoang Truong ◽  
Phuc Van Pham

Introduction: Embryonic stem cells are pluripotent, thus capable of differentiating into all types of cells derived from the three germ layers. However, the application of embryonic stem cells (ESCs) for preclinical and clinical studies is difficult due to ethical concerns. Induced pluripotent stem cells (iPSCs) are derived from differentiation and have many ESC characteristics. The study herein examines the production of iPSCs from reprogramming of mouse embryonic fibroblasts (MEFs) via transduction with defined factors. Methods: MEFs were collected from mouse embryos via a previously published protocol. The cells were transduced with a single polycistronic viral vector encoding mouse cDNAs of Oct3/4, Sox2, Klf4 and c-Myc. Transduced cells were treated and sub-cultured with ESC medium. The cells were evaluated as iPSCs with specific morphology, and expression SSEA-1, Oct3/4, Sox2 and Nanog. In addition, they also were evaluated for pluripotency by assessing alkaline phosphatase (AP) activity and in vivo teratoma formation. Results: Under the reprogrammed conditions, the transduced cells displayed a change in morphology, forming ESC-like clusters. These cell clusters strongly expressed pluripotent markers as well as ESC-specific genes. Furthermore, the colonies exhibited higher AP activity and formed teratomas when injected into the murine testis. Conclusions: The study herein suggests that MEFs can be reprogrammed into iPSCs using a polycistronic viral vector encoding mouse cDNAs for Oct3/4, Sox2, Klf4 and c-Myc.  


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