51
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Zhang L, Luo YB, Bou G, Kong QR, Huan YJ, Zhu J, Wang JY, Li H, Wang F, Shi YQ, Wei YC, Liu ZH. Overexpression Nanog activates pluripotent genes in porcine fetal fibroblasts and nuclear transfer embryos. Anat Rec (Hoboken) 2011; 294:1809-17. [PMID: 21972213 DOI: 10.1002/ar.21457] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 05/31/2011] [Accepted: 06/12/2011] [Indexed: 02/05/2023]
Abstract
Nanog as an important transcription factor plays a pivotal role in maintaining pluripotency and in reprogramming the epigenome of somatic cells. Its ability to function on committed somatic cells and embryos has been well defined in mouse and human, but rarely in pig. To better understand Nanog's function on reprogramming in porcine fetal fibroblast (PFF) and nuclear transfer (NT) embryo, we cloned porcine Nanog CDS and constructed pcDNA3.1 (+)/Nanog and pEGFP-C1/Nanog overexpression vectors and transfected them into PFFs. We studied the cell biological changes and the expression of Nanog, Oct4, Sox2, Klf4, C-myc, and Sall4 in transfected PFFs. We also detected the development potential of the cloned embryos harboring Nanog stably overexpressed fibroblasts and the expression of Oct4, Sox2, and both endogenous and exogenous Nanog in these embryos. The results showed that transient overexpression Nanog in PFF could activate the expression of Oct4 (5-fold), C-myc (2-fold), and Sall4 (5-fold) in somatic cells, but they could not be maintained during G418 selection. In NT embryos, although Nanog overexpression did not have a significant effect on blastocyst development rate and blastocyst cell number, it could significantly activate the expression of endogenous Nanog, Oct4, Sox2 to 160-fold, 93-fold, and 182-fold, respectively (P < 0.05). Our results demonstrate that Nanog could interact with and activate other pluripotent genes both in PFFs and embryos.
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Affiliation(s)
- Li Zhang
- Department of Life Science, Northeast Agriculture University, Heilongjiang Province, China
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52
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Gao Y, Hyttel P, Hall VJ. Dynamic Changes in Epigenetic Marks and Gene Expression During Porcine Epiblast Specification. Cell Reprogram 2011; 13:345-60. [DOI: 10.1089/cell.2010.0110] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Yu Gao
- Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Denmark
| | - Poul Hyttel
- Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Denmark
| | - Vanessa Jane Hall
- Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences, University of Copenhagen, Denmark
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53
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Nowak-Imialek M, Kues W, Carnwath JW, Niemann H. Pluripotent stem cells and reprogrammed cells in farm animals. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2011; 17:474-497. [PMID: 21682936 DOI: 10.1017/s1431927611000080] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Pluripotent cells are unique because of their ability to differentiate into the cell lineages forming the entire organism. True pluripotent stem cells with germ line contribution have been reported for mice and rats. Human pluripotent cells share numerous features of pluripotentiality, but confirmation of their in vivo capacity for germ line contribution is impossible due to ethical and legal restrictions. Progress toward derivation of embryonic stem cells from domestic species has been made, but the derived cells were not able to produce germ line chimeras and thus are termed embryonic stem-like cells. However, domestic animals, in particular the domestic pig (Sus scrofa), are excellent large animals models, in which the clinical potential of stem cell therapies can be studied. Reprogramming technologies for somatic cells, including somatic cell nuclear transfer, cell fusion, in vitro culture in the presence of cell extracts, in vitro conversion of adult unipotent spermatogonial stem cells into germ line derived pluripotent stem cells, and transduction with reprogramming factors have been developed with the goal of obtaining pluripotent, germ line competent stem cells from domestic animals. This review summarizes the present state of the art in the derivation and maintenance of pluripotent stem cells in domestic animals.
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Affiliation(s)
- Monika Nowak-Imialek
- Institute of Farm Animal Genetics (FLI), Biotechnology, Mariensee, 31535 Neustadt, Germany
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54
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Ruan W, Han J, Li P, Cao S, An Y, Lim B, Li N. A novel strategy to derive iPS cells from porcine fibroblasts. SCIENCE CHINA. LIFE SCIENCES 2011; 54:553-9. [PMID: 21706416 DOI: 10.1007/s11427-011-4179-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Accepted: 04/23/2011] [Indexed: 12/14/2022]
Abstract
Induced pluripotent stem (iPS) cell technology demonstrates that somatic cells can be reprogrammed to a pluripotent state by over-expressing four reprogramming factors. This technology has created an interest in deriving iPS cells from domesticated animals such as pigs, sheep and cattle. Moloney murine leukemia retrovirus vectors have been widely used to generate and study mouse iPS cells. However, this retrovirus system infects only mouse and rat cells, which limits its use in establishing iPS cells from other mammals. In our study, we demonstrate a novel retrovirus strategy to efficiently generate porcine iPS cells from embryonic fibroblasts. We transfected four human reprogramming factors (Oct4, Sox2, Klf4 and Myc) into fibroblasts in one step by using a VSV-G envelope-coated pantropic retrovirus that was easily packaged by GP2-293 cells. We established six embryonic stem (ES)-like cell lines in human ES cell medium supplemented with bFGF. Colonies showed a similar morphology to human ES cells with a high nuclei-cytoplasm ratio and phase-bright flat colonies. Porcine iPS cells could form embryoid bodies in vitro and differentiate into the three germ layers in vivo by forming teratomas in immunodeficient mice.
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Affiliation(s)
- WeiMin Ruan
- State Key Laboratory for Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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55
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Petkov SG, Marks H, Klein T, Garcia RS, Gao Y, Stunnenberg H, Hyttel P. In vitro culture and characterization of putative porcine embryonic germ cells derived from domestic breeds and Yucatan mini pig embryos at Days 20–24 of gestation. Stem Cell Res 2011; 6:226-37. [DOI: 10.1016/j.scr.2011.01.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/18/2011] [Accepted: 01/18/2011] [Indexed: 12/21/2022] Open
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56
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Dang-Nguyen TQ, Somfai T, Haraguchi S, Kikuchi K, Tajima A, Kanai Y, Nagai T. In vitro production of porcine embryos: current status, future perspectives and alternative applications. Anim Sci J 2011; 82:374-82. [PMID: 21615829 DOI: 10.1111/j.1740-0929.2011.00883.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The pig is considered to be a suitable source of cells and organs for xenotransplants, as well as a transgenic animal to produce specific proteins, given the biological similarities it shares with human beings. However, the in vitro embryo production system in pigs is inefficient compared with those in other mammals, such as cattle or mice. Although numerous modifications have been applied to improve the efficiency of in vitro embryo production systems in pigs, not much progress has been made to overcome the problem of polyspermy, and low developmental ability due to insufficient cytoplasmic abilities of in vitro matured oocytes and improper culture conditions for the in vitro produced embryos. Recent achievements, such as the establishment of chemically defined medium and utilization of 'zona hardening' technique, have gained some success. However, further research for the reduction of polyspermy and detrimental effects of the culture systems in pigs is still needed.
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Affiliation(s)
- Thanh Quang Dang-Nguyen
- National Institute of Livestock and Grassland Science, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan
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57
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[Progress and application prospect of pig induced pluripotent stem cells]. YI CHUAN = HEREDITAS 2011; 33:307-13. [PMID: 21482519 DOI: 10.3724/sp.j.1005.2011.00307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Pig has always been the focus of establishing a big ungulate animal ES cell lines because of its convenient source, genetic similarity with humans, and their importance in animal husbandry, but little development is achieved. Induced pluripotent stem cells technology creates a new method of reprogramming somatic cells to pluripotent state. As the pig iPS cells is established and perfected, pig ES cells will be established in the coming years. The pig iPS cells will give a hint on other livestock ES cells. On the other hand, pig iPS cells can be used to improve the efficiency of transgenic cloning pigs to conduct effective breeding and conservation of breeds. It is particularly important that the pig iPS cells can provide new model for human medical research, a new donor cells for human tissue and organ engineering, and have extensive and far-reaching impact on the biomedical field. Here, we briefly review the major progress of iPS cells, and emphasize current state of pig iPS cells and its application prospect in biomedicine and animal husbandry in order to provide a useful reference for researchers working in this area.
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58
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Hall VJ, Jacobsen JV, Rasmussen MA, Hyttel P. Ultrastructural and molecular distinctions between the porcine inner cell mass and epiblast reveal unique pluripotent cell states. Dev Dyn 2011; 239:2911-20. [PMID: 20865782 DOI: 10.1002/dvdy.22424] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Characterization of the pluripotent cell populations within the porcine embryo is essential for understanding pluripotency and self-renewal regulation in the inner cell mass (ICM) and epiblast. In this study, we perform detailed ultrastructural and molecular characterization of the developing pluripotent cell population as it develops from the ICM to the late epiblast. The ultrastructural observations revealed that the outer cells of the ICM have a high nuclear:cytoplasmic ratio but are transcriptionally inactive and contain mitochondria with few cristae. In contrast, the epiblast cells have a reduced nuclear:cytoplasmic ratio, are more transcriptionally active, and contain abundant cellular organelles. This study also revealed cavitation and potential unfolding of the epiblast. As the ICM forms the epiblast, SSEA1 is lost and VIMENTIN is lost and re-expressed. The D6 blastocyst expressed high levels of STELLA, TERF1, and GDF3, and the epiblast expressed epithelial markers, MUC1 and E-CADHERIN, and the pluripotency markers, DNMT3B and CRIPTO.
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Affiliation(s)
- Vanessa J Hall
- Department of Basic Animal and Veterinary Sciences, Faculty of LIFE Sciences, University of Copenhagen, Copenhagen, Denmark.
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59
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Nowak-Imialek M, Kues WA, Petersen B, Lucas-Hahn A, Herrmann D, Haridoss S, Oropeza M, Lemme E, Schöler HR, Carnwath JW, Niemann H. Oct4-enhanced green fluorescent protein transgenic pigs: a new large animal model for reprogramming studies. Stem Cells Dev 2011; 20:1563-75. [PMID: 21126163 DOI: 10.1089/scd.2010.0399] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The domesticated pig has emerged as an important tool for development of surgical techniques, advancement of xenotransplantation, creation of important disease models, and preclinical testing of novel cell therapies. However, germ line-competent pluripotent porcine stem cells have not yet been derived. This has been a major obstacle to genetic modification of pigs. The transcription factor Oct4 is essential for the maintenance of pluripotency and for reprogramming somatic cells to a pluripotent state. Here, we report the production of transgenic pigs carrying an 18 kb genomic sequence of the murine Oct4 gene fused to the enhanced green fluorescent protein (EGFP) cDNA (OG2 construct) to allow identification of pluripotent cells by monitoring Oct4 expression by EGFP fluorescence. Eleven viable transgenic piglets were produced by somatic cell nuclear transfer. Expression of the EGFP reporter construct was confined to germ line cells, the inner cell mass and trophectoderm of blastocysts, and testicular germ cells. Reprogramming of fibroblasts from these animals by fusion with pluripotent murine embryonic stem cells or viral transduction with human OCT4, SOX2, KLF4, and c-MYC cDNAs resulted in Oct4-EGFP reactivation. The OG2 pigs have thus proved useful for monitoring reprogramming and the induction and maintenance of pluripotency in porcine cells. In conclusion, the OG2 transgenic pigs are a new large animal model for studying the derivation and maintenance of pluripotent cells, and will be valuable for the development of cell therapy.
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Affiliation(s)
- Monika Nowak-Imialek
- Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut, Neustadt, Germany
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60
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Ezashi T, Telugu BPVL, Roberts RM. Generation and Characterization of Induced Pluripotent Stem Cells from Pig. STEM CELL BIOLOGY AND REGENERATIVE MEDICINE 2011. [DOI: 10.1007/978-1-60761-860-7_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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61
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Characterization, isolation and culture of primordial germ cells in domestic animals: recent progress and insights from the ovine species. Theriogenology 2010; 74:534-43. [DOI: 10.1016/j.theriogenology.2010.05.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 05/06/2010] [Accepted: 05/06/2010] [Indexed: 02/08/2023]
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62
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Esteban MA, Peng M, Deli Z, Cai J, Yang J, Xu J, Lai L, Pei D. Porcine induced pluripotent stem cells may bridge the gap between mouse and human iPS. IUBMB Life 2010; 62:277-82. [PMID: 20101630 DOI: 10.1002/iub.307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Recently, three independent laboratories reported the generation of induced pluripotent stem cells (iPSCs) from pig (Sus scrofa). This finding sums to the growing list of species (mouse, human, monkey, and rat, in this order) for which successful reprogramming using exogenous factors has been achieved, and multiple others are possibly forthcoming. But apart from demonstrating the universality of the network identified by Shinya Yamanaka, what makes the porcine model so special? On one side, pigs are an agricultural commodity and have an easy and affordable maintenance compared with nonhuman primates that normally need to be imported. On the other side, resemblance (for example, size of organs) of porcine and human physiology is striking and because pigs are a regular source of food the ethical concerns that still remain in monkeys are not applicable. Besides, the prolonged lifespan of pigs compared with other domestic species can allow exhaustive follow up of side effects after transplantation. Porcine iPSCs may thus fill the gap between the mouse model, which due to its ease is preferred for mechanistic studies, and the first clinical trials using iPSCs in humans. However, although these studies are relevant and have created significant interest they face analogous problems that we discuss herein together with potential new directions.
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Affiliation(s)
- Miguel A Esteban
- Stem Cell and Cancer Biology Group, Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
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63
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Hall VJ, Christensen J, Gao Y, Schmidt MH, Hyttel P. Porcine pluripotency cell signaling develops from the inner cell mass to the epiblast during early development. Dev Dyn 2009; 238:2014-24. [PMID: 19618464 DOI: 10.1002/dvdy.22027] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The signaling mechanisms regulating pluripotency in porcine embryonic stem cells and embryos are unknown. In this study, we characterize cell signaling in the in-vivo porcine inner cell mass and later-stage epiblast. We evaluate expression of OCT4, NANOG, SOX2, genes within the JAK/STAT pathway (LIF, LIFR, GP130), FGF pathway (bFGF, FGFR1, FGFR2), BMP pathway (BMP4), and downstream-activated genes (STAT3, c-Myc, c-Fos, and SMAD4). We discovered two different expression profiles exist in the developing porcine embryo. The D6 porcine blastocyst (inner cell mass stage) is devoid in the expression of most genes analyzed, with the exception of OCT4. In contrast, the D11 epiblast expressed 10 of the 12 genes investigated. Immunocytochemistry confirmed LIFR and bFGF was not expressed in the epiblast, but within the trophectoderm. These findings reveal cell signaling associated with maintaining pluripotency in human embryonic stem cells is detectable in the porcine epiblast, but not in the inner cell mass.
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Affiliation(s)
- Vanessa J Hall
- Department of Basic Animal and Veterinary Sciences, Faculty of Life Sciences University of Copenhagen, Copenhagen, Denmark.
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64
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Oestrup O, Hall V, Petkov SG, Wolf XA, Hyldig S, Hyttel P. From Zygote to Implantation: Morphological and Molecular Dynamics during Embryo Development in the Pig. Reprod Domest Anim 2009; 44 Suppl 3:39-49. [DOI: 10.1111/j.1439-0531.2009.01482.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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65
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Cervera RP, Silvestre MA, Martí N, García-Mengual E, Moreno R, Stojkovic M. Effects of different oocyte activation procedures on development and gene expression of porcine pre-implantation embryos. Reprod Domest Anim 2009; 45:e12-20. [PMID: 19663811 DOI: 10.1111/j.1439-0531.2009.01509.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Among the factors that affect the efficiency of somatic cell nuclear transfer (SCNT) in pigs, the activation protocol is the most variable among the current SCNT procedures. The aim of this study is focused on defining an efficient activation treatment of porcine oocytes. In Experiment 1, we studied the effects of nine different oocyte activation procedures (including chemical- and electrical-based treatments) on parthenogenetic embryo development. In Experiment 2, we studied the effect of the more efficient activation procedures on the gene expression profile of Oct4 and Igf2r in parthenogenetic blastocysts. In conclusion, ionomycin as a first calcium stimulus is not able to activate porcine oocytes efficiently in comparison with electric procedures. Electrical treatments with 6-DMAP significantly increased the level of Oct4 expression, whereas the single and double pulse treatments alone maintained the same profile as the IVF group.
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Affiliation(s)
- R P Cervera
- Cellular Reprogramming Laboratory, Centro de Investigación Príncipe Felipe, Avenida Autopista del Saler, Valencia, Spain.
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66
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Abstract
For reasons that are unclear the production of embryonic stem cells from ungulates has proved elusive. Here, we describe induced pluripotent stem cells (iPSC) derived from porcine fetal fibroblasts by lentiviral transduction of 4 human (h) genes, hOCT4, hSOX2, hKLF4, and hc-MYC, the combination commonly used to create iPSC in mouse and human. Cells were cultured on irradiated mouse embryonic fibroblasts (MEF) and in medium supplemented with knockout serum replacement and FGF2. Compact colonies of alkaline phosphatase-positive cells emerged after approximately 22 days, providing an overall reprogramming efficiency of approximately 0.1%. The cells expressed porcine OCT4, NANOG, and SOX2 and had high telomerase activity, but also continued to express the 4 human transgenes. Unlike human ESC, the porcine iPSC (piPSC) were positive for SSEA-1, but negative for SSEA-3 and -4. Transcriptional profiling on Affymetrix (porcine) microarrays and real time RT-PCR supported the conclusion that reprogramming to pluripotency was complete. One cell line, ID6, had a normal karyotype, a cell doubling time of approximately 17 h, and has been maintained through >220 doublings. The ID6 line formed embryoid bodies, expressing genes representing all 3 germ layers when cultured under differentiating conditions, and teratomas containing tissues of ectoderm, mesoderm, and endoderm origin in nude mice. We conclude that porcine somatic cells can be reprogrammed to form piPSC. Such cell lines derived from individual animals could provide a means for testing the safety and efficacy of stem cell-derived tissue grafts when returned to the same pigs at a later age.
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67
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Esteban MA, Xu J, Yang J, Peng M, Qin D, Li W, Jiang Z, Chen J, Deng K, Zhong M, Cai J, Lai L, Pei D. Generation of induced pluripotent stem cell lines from Tibetan miniature pig. J Biol Chem 2009; 284:17634-40. [PMID: 19376775 DOI: 10.1074/jbc.m109.008938] [Citation(s) in RCA: 328] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Induced pluripotent stem cell (iPS) technology appears to be a general strategy to generate pluripotent stem cells from any given mammalian species. So far, iPS cells have been reported for mouse, human, rat, and monkey. These four species have also established embryonic stem cell (ESC) lines that serve as the gold standard for pluripotency comparisons. Attempts have been made to generate porcine ESC by various means without success. Here we report the successful generation of pluripotent stem cells from fibroblasts isolated from the Tibetan miniature pig using a modified iPS protocol. The resulting iPS cell lines more closely resemble human ESC than cells from other species, have normal karyotype, stain positive for alkaline phosphatase, express high levels of ESC-like markers (Nanog, Rex1, Lin28, and SSEA4), and can differentiate into teratomas composed of the three germ layers. Because porcine physiology closely resembles human, the iPS cells reported here provide an attractive model to study certain human diseases or assess therapeutic applications of iPS in a large animal model.
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Affiliation(s)
- Miguel A Esteban
- Stem Cell and Cancer Biology Group, Chinese Academy of Sciences Key Laboratory of Regenerative Biology, South China Institute for Stem Cell Biology and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Guangzhou 510663, USA
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