https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/49782/1/Yamanaka_Cell_131_5.pdf

Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors

Somatic cell nuclear transfer allows trans-acting factors present in the mammalian oocyte to reprogram somatic cell nuclei to an undifferentiated state. We show that four factors (OCT4, SOX2, NANOG, and LIN28) are sufficient to reprogram human somatic cells to pluripotent stem cells that exhibit the essential characteristics of embryonic stem (ES) cells. These induced pluripotent human stem cells have normal karyotypes, express telomerase activity, express cell surface markers and genes that characterize human ES cells, and maintain the developmental potential to differentiate into advanced derivatives of all three primary germ layers. Such induced pluripotent human cell lines should be useful in the production of new disease models and in drug development, as well as for applications in transplantation medicine, once technical limitations (for example, mutation through viral integration) are eliminated.

https://science.sciencemag.org/content/sci/318/5858/1917.full.pdf

Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells

The transcription factor NF-kappaB has been the focus of intense investigation for nearly two decades. Over this period, considerable progress has been made in determining the function and regulation of NF-kappaB, although there are nuances in this important signaling pathway that still remain to be understood. The challenge now is to reconcile the regulatory complexity in this pathway with the complexity of responses in which NF-kappaB family members play important roles. In this review, we provide an overview of established NF-kappaB signaling pathways with focus on the current state of research into the mechanisms that regulate IKK activation and NF-kappaB transcriptional activity.

/pdf/signaling-to-nf-kappab-1zyb7vgt7s.pdf

Signaling to NF-kappaB.

The complexity of the human brain has made it difficult to study many brain disorders in model organisms, highlighting the need for an in vitro model of human brain development Here we have developed a human pluripotent stem cell-derived three-dimensional organoid culture system, termed cerebral organoids, that develop various discrete, although interdependent, brain regions These include a cerebral cortex containing progenitor populations that organize and produce mature cortical neuron subtypes Furthermore, cerebral organoids are shown to recapitulate features of human cortical development, namely characteristic progenitor zone organization with abundant outer radial glial stem cells Finally, we use RNA interference and patient-specific induced pluripotent stem cells to model microcephaly, a disorder that has been difficult to recapitulate in mice We demonstrate premature neuronal differentiation in patient organoids, a defect that could help to explain the disease phenotype Together, these data show that three-dimensional organoids can recapitulate development and disease even in this most complex human tissue

/pdf/cerebral-organoids-model-human-brain-development-and-3wt90buxu3.pdf

Cerebral organoids model human brain development and microcephaly

Pluripotency pertains to the cells of early embryos that can generate all of the tissues in the organism. Embryonic stem cells are embryo-derived cell lines that retain pluripotency and represent invaluable tools for research into the mechanisms of tissue formation. Recently, murine fibroblasts have been reprogrammed directly to pluripotency by ectopic expression of four transcription factors (Oct4, Sox2, Klf4 and Myc) to yield induced pluripotent stem (iPS) cells. Using these same factors, we have derived iPS cells from fetal, neonatal and adult human primary cells, including dermal fibroblasts isolated from a skin biopsy of a healthy research subject. Human iPS cells resemble embryonic stem cells in morphology and gene expression and in the capacity to form teratomas in immune-deficient mice. These data demonstrate that defined factors can reprogramme human cells to pluripotency, and establish a method whereby patient-specific cells might be established in culture.

/pdf/reprogramming-of-human-somatic-cells-to-pluripotency-with-4lycgkg8te.pdf

Reprogramming of human somatic cells to pluripotency with defined factors

Negative regulation of hematopoiesis by the fused in myeloproliferative disorders gene product.

We have previously shown that embryonic stem (ES)-like cells can be induced from mouse fibroblasts, hepatocytes and stomach epithelial cells by introducing four factors (Oct3/4, Sox2, c-Myc, and Klf4). The cells are similar in morphology, proliferation and gene expression profile to those of ES cells, and are called induced pluripotent stem (iPS) cells. When the iPS cells are transferred into blastocyst, they can contribute to adult chimeric mice and transmit through germline to the next generation. Therefore iPS cells have almost same differentiation potential as ES cells. In 2007, we and others reported the establishment of iPS cells from human somatic cells and showed their pluripotency.These iPS cells would supply patient-specific pluripotent stem cells for cell transplantation therapies. However, iPS cells still have several problems to be overcome, especially tumorigenicity owing to the use of oncogenes and retrovirus. Recent studies revealed that c-Myc is not a crucial factor for iPS induction, albeit it greatly increases the efficiency. The improvement of reprogramming efficiency was reported with soluble factor, Wnt3a, and several small molecules that influence epigenetic modification, such as BIX-01294 and VPA. Induction of mouse iPS cells without virus vector has been reported. Through the basic researches on iPS and ES cells, molecular mechanisms underlying the reprogramming process were gradually being uncovered. Here we try to summarize current studies on iPS cells. The iPS cells will contribute to the fields ofelucidation of pathogenesis, drug discovery, toxicology study, and cell transplantation therapy in the future.

/pdf/recent-advance-in-induced-pluripotent-stem-cells-55lqed6gfl.pdf

Recent advance in induced pluripotent stem cells

The reprogramming of somatic cells has been extensively investigated. Successful studies have yielded the generation of cloned animals from frog and sheep somatic cells. The somatic cells were fused with enucleated oocyte in those studies, which indicated the existence of a reprogramming factor in the oocyte. Embryonic stem (ES) cells derived from early embryonic tissue have similar activity, and can reprogram somatic cells by cell fusion. Reprogramming was then accomplished with defined factors (Oct3/4, Sox2, Klf4, and c-Myc), which are expressed abundantly in ES cells and pluripotent stem cells emerged. These artificial cells were termed induced pluripotent stem (iPS) cells; they have similar morphology, proliferation, and gene expression profile to those of ES cells. These in vitro reprogrammed cells attract a lot of attention because they have potential to supply patient-specific pluripotent stem cells to many fields, such as the study of disease pathogenesis, drug discovery, toxicology, and someday maybe even cell therapy.

Chapter 26 – Induced Pluripotent Stem Cells

A method of producing an induced pluripotent stem cell includes introducing into a somatic cell one or more non-viral expression vectors. The vectors include one or more of an Oct family gene, a Klf family gene, a Sox family gene, a Myc family gene, a Lin family gene, and Nanog gene. The somatic cell is then cultured in a medium that supports pluripotent stem cells. At least a portion of the one or more introduced non-viral expression vectors is not substantially integrated in the chromosome.

Method of making induced pluripotent stem cells

La presente invention concerne un procede d'amelioration de l'efficacite d'etablissement de cellules souches pluripotentes induites (iPS), comprenant l'etape consistant a inhiber la fonction p53 dans l'etape de reprogrammation nucleaire des cellules somatiques. L'inhibition de la fonction p53 est obtenue en amenant une substance choisie dans le groupe comprenant (1) des inhibiteurs chimiques du p53, (2) des mutants negatifs dominants du p53 et des acides nucleiques qui codent pour ceux-ci, (3) des ARNsi et des ARNsh contre le p53 et des ADN qui codent pour ceux-ci, et (4) des inhibiteurs de la voie du p53, en contact avec une cellule somatique, et equivalents. La presente invention concerne egalement un agent pour ameliorer l'efficacite d'etablissement de cellules iPS, l'agent comprenant un inhibiteur de la fonction p53, en particulier (1) des inhibiteurs chimiques du p53, (2) des mutants negatifs dominants du p53 et des acides nucleiques qui codent pour ceux-ci, (3) des ARNsi et des ARNsh contre le p53 et des ADN qui codent pour ceux-ci, et (4) des inhibiteurs de la voie du p53. La presente invention concerne en outre un procede de production d'une cellule iPS, comprenant l'etape consistant a amener en contact une substance de reprogrammation nucleaire et un inhibiteur de la fonction p53 avec une cellule somatique.

Keisuke Okita

Papers

Negative regulation of hematopoiesis by the fused in myeloproliferative disorders gene product.

Recent advance in induced pluripotent stem cells

Chapter 26 – Induced Pluripotent Stem Cells

Method of making induced pluripotent stem cells

Procédé consistant à établir efficacement des cellules souches pluripotentes induites