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Encyclopedia > Embryonic stem cell
Human embryonic stem cell colony.
Human embryonic stem cell colony.
Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.
Pluripotent, embryonic stem cells originate as inner mass cells within a blastocyst. The stem cells can become any tissue in the body, excluding a placenta. Only the morula's cells are totipotent, able to become all tissues and a placenta.

Embryonic stem cells (ES cells) are stem cells derived from the inner cell mass of an early stage embryo known as a blastocyst. Human embryos reach the blastocyst stage 4-5 days post fertilization, at which time they consist of 50-150 cells. Image File history File linksMetadata Download high-resolution version (3072x2304, 2465 KB) Here is an actual picture of an embryonic stem cell. ... Image File history File linksMetadata Download high-resolution version (3072x2304, 2465 KB) Here is an actual picture of an embryonic stem cell. ... Image File history File links Download high-resolution version (1031x943, 169 KB) Other versions Image:StemCellsDia. ... Image File history File links Download high-resolution version (1031x943, 169 KB) Other versions Image:StemCellsDia. ... Mouse embryonic stem cells with fluorescent marker. ... For other uses, see Embryo (disambiguation). ... The blastocyst is an early stage of the human (or any other mammal) development early in pregnancy. ... The acrosome reaction for a sea urchin, a similar process. ...


Embryonic Stem (ES) cells are pluripotent. This means they are able to differentiate into all derivatives of the three primary germ layers: ectoderm, endoderm, and mesoderm. These include each of the more than 220 cell types in the adult body. Pluripotency distinguishes ES cells from multipotent progenitor cells found in the adult; these only form a limited number of cell types. When given no stimuli for differentiation, (i.e. when grown in vitro), ES cells maintain pluripotency through multiple cell divisions. The presence of pluripotent adult stem cells remains a subject of scientific debate, however, research has demonstrated that pluripotent stem cells can be directly generated from adult fibroblast cultures.[1] In cell biology, a pluripotent cell is one able to differentiate into many cell types. ... Embryonic stem cells differentiate into cells in various body organs. ... Organs derived from each germ layer. ... The ectoderm is outermost of the three germ layers of the developing embryo, the other two being the mesoderm and the endoderm. ... Endoderm is one of the germ layers formed during animal embryogenesis. ... The mesoderm is one of the three germ layers in the early developing embryo, the other two layers being the ectoderm and the endoderm. ... Physical Features of the Human Body The human body is the entire physical structure of a human organism. ... Multipotent progenitor cells can give rise to several other cell types, but those types are limited in number. ... The term progenitor cell is used in cell biology and developmental biology to refer to immature or undifferentiated cells, typically found in post-natal animals. ... In vitro (Latin: within the glass) refers to the technique of performing a given experiment in a test tube, or, generally, in a controlled environment outside a living organism. ... This does not adequately cite its references or sources. ... Adult stem cells can be found in all adults and young adults. ... NIH/3T3 Fibroblasts A fibroblast is a type of cell that synthesizes and maintains the extracellular matrix of many animal tissues. ...


Because of their plasticity and potentially unlimited capacity for self-renewal, ES cell therapies have been proposed for regenerative medicine and tissue replacement after injury or disease. However, to date, no approved medical treatments have been derived from embryonic stem cell research (ESCR). Adult stem cells and cord blood stems cells have thus far been the only stem cells used to successfully treat any diseases. Diseases treated by these non-embryonic stem cells include a number of blood and immune-system related genetic diseases, cancers, and disorders; juvenile diabetes; Parkinson's; blindness and spinal cord injuries. Besides the ethical problems of stem cell therapy (see stem cell controversy), there is a technical problem of graft-versus-host disease associated with allogeneic stem cell transplantation. However, these problems associated with histocompatibility may be solved using autologous donor adult stem cells or via therapeutic cloning. There is widespread controversy over stem cell research largely due to techniques used in the creation and usage of human embryonic stem cells. ... Graft-versus-host disease (GVHD) is a common complication of allogeneic bone marrow transplantation in which functional immune cells in the transplanted marrow recognize the recipient as foreign and mount an immunologic attack. ... Bone marrow transplantation (BMT) or hematopoietic stem cell transplantation (HSCT) is a medical procedure in the field of hematology and oncology that involves transplantation of hematopoietic stem cells (HSC). ... This article or section does not adequately cite its references or sources. ... In biology, autologous refers to cells, tissues or even proteins that are reimplanted in the same individual as they come from. ... Adult stem cells can be found in all adults and young adults. ... Blastocyst. ...

Contents

Research history and developments

Isolation and in vitro culture

Stem cells were discovered from analysis of a type of cancer called a teratocarcinoma. In 1964, researchers noted that a single cell in teratocarcinomas could be isolated and remain undifferentiated in culture. These types of stem cells became known as embryonic carcinoma cells (EC cells).[2] Researchers learned that primordial embryonic germ cells (EG cells) could be cultured and stimulated to produce many different cell types. A teratocarcinoma or germ cell tumour (GCT) is a malignant tumour containing elements of teratomas and embryonal carcinomas. ...


Embryonic stem cells (ES cells) were first derived from mouse embryos in 1981 by Martin Evans and Matthew Kaufman and independently by Gail R. Martin. Gail R. Martin is credited with coining the term 'Embryonic Stem Cell'.[3][4] A breakthrough in human embryonic stem cell research came in November 1998 when a group led by James Thomson at the University of Wisconsin-Madison first developed a technique to isolate and grow the cells when derived from human blastocysts.[5] Sir Martin Evans is a British scientist, he is credited with discovering embryonic stem cells in 1981, and for the development of the knockout mouse Categories: Geneticists | Scientist stubs ... In 1981 Matthew H. Kaufman and Martin Evans at the University of Cambridge in England and Gail R Martin in America were the first to derive embryonic stem cells (ES cells) from mouse embryos. ... James Jamie Alexander Thomson (born in Oak Park, Illinois) is an American developmental biologist who also serves as a professor of anatomy in the University of Wisconsin School of Medicine and Public Health and as the chief pathologist at the Wisconsin National Primate Research Center. ... University of Wisconsin redirects here. ...


Production of male gametes

Researchers at the Whitehead Institute announced in 2003 that they had successfully used embryonic stem cells to produce haploid, male gametes. They found embryonic stem cells that had begun to differentiate into embryonic germ cells and then further differentiated into the male haploid cells. When injected into oocytes, these haploid cells restored the somatic diploid complement of chromosomes and formed blastocysts in vitro.[6] Founded in 1984, the Whitehead Institute for Biomedical Research is a non-profit research and teaching institution located in Cambridge, Massachusetts. ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... A germ cell is part of the germline and is involved in the reproduction of organisms. ... An oocyte or ovocyte is a female gametocyte that divides twice by mitosis and meiosis into two other oocytes or into two ootids. ... Diploid (meaning double in Greek) cells have two copies (homologs) of each chromosome (both sex- and non-sex determining chromosomes), usually one from the mother and one from the father. ... This article is about the biological chromosome. ... In vitro (Latin: within the glass) refers to the technique of performing a given experiment in a test tube, or, generally, in a controlled environment outside a living organism. ...


Contamination by reagents used in cell culture

The online edition of Nature Medicine published a study on January 23, 2005 which stated that the human embryonic stem cells available for federally funded research are contaminated with non-human molecules from the culture medium used to grow the cells. It is a common technique to use mouse cells and other animal cells to maintain the pluripotency of actively dividing stem cells. The problem was discovered when non-human sialic acid in the growth media was found to compromise the potential uses of the embryonic stem cells in humans, according to scientists at the University of California, San Diego.[7] is the 23rd day of the year in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... Sialic acid is a generic term for the N- or O-substituted derivatives of neuraminic acid, a nine-carbon monosaccharide. ... The University of California, San Diego (popularly known as UCSD, or sometimes UC San Diego) is a highly selective, research-oriented[1] public university located in La Jolla, a seaside resort community of San Diego, California. ...


However, a study published in the online edition of Lancet Medical Journal on March 8, 2005 detailed information about a new stem cell line which was derived from human embryos under completely cell- and serum-free conditions. After more than 6 months of undifferentiated proliferation, these cells demonstrated the potential to form derivatives of all three embryonic germ layers both in vitro and in teratomas. These properties were also successfully maintained (for more than 30 passages) with the established stem cell lines.[8] is the 67th day of the year (68th in leap years) in the Gregorian calendar. ... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... Look up teratoma in Wiktionary, the free dictionary. ...


Reducing donor-host rejection

There is also ongoing research to reduce the potential for rejection of the differentiated cells derived from ES cells once researchers are capable of creating an approved therapy from ES cell research. One of the possibilities to prevent rejection is by creating embryonic stem cells that are genetically identical to the patient via therapeutic cloning. Blastocyst. ...


An alternative solution for rejection by the patient to therapies derived from non-cloned ES cells is to derive many well-characterized ES cell lines from different genetic backgrounds and use the cell line that is most similar to the patient; treatment can then be tailored to the patient, minimizing the risk of rejection.


Potential method for new cell line derivation

On August 23, 2006, the online edition of Nature scientific journal published a letter by Dr. Robert Lanza (medical director of Advanced Cell Technology in Worcester, MA) stating that his team had found a way to extract embryonic stem cells without destroying the actual embryo.[9] This technical achievement would potentially enable scientists to work with new lines of embryonic stem cells derived using public funding. Federal funding is currently limited to research using embryonic stem cell lines derived prior to August 2001. Nature is a prominent scientific journal, first published on 4 November 1869. ... Dr Robert Lanza is Vice President of Research and Scientific Development Advanced Cell Technology (ACT) and Adjunct Professor at the Institute of Regenerative Medicine, Wake Forest University School of Medicine [1]. Lanza received both BA and MD degrees from the University of Pennsylvania. ... Human cloning is supposed to be band, if anyone cared why is this web page blank!!!!! you mean banned--^ ...

See also: Induced pluripotent stem cell

Professor Yamanaka had a recent breakthrough[10] in which the skin cells of laboratory mice were genetically manipulated back to their embryonic state. This work was confirmed by two other groups, demonstrating that the addition of just 4 genes (Oct3/4, Sox3, Klf4, and Myc) could reprogram mouse skin cells into embryonic stem like cells. The ability to reproduce such findings are very important in science and the stem cell field, especially after Hwang Woo-Suk from Korea fabricated data, claiming to have generated human ES cells from cloned embryos. These cells produced by Yamanaka as well as the other laboratories demonstrated all the hallmarks of embryonic stem cells including the ability to form chimeric mice and contribute to the germ-line. One issue with this work is that the mice generated from these ES lines were prone to develop cancer due to the use of Myc, which is a known oncogene. Hwang Woo-suk (황우석) (born 29 January 1953) is a South Korean biomedical scientist. ...


On 20th of November, 2007, two research teams, one of which was headed by Professor Yamanaka and the other by James Thomson[11] announced a similar breakthrough with ordinary human skin cells that were transformed into batches of cells that look and act like embryonic stem cells. This may enable the generation of patient specific ES cell lines that could potentially be used for cell replacement therapies. In addition, this will allow the generation of ES cell lines from patients with a variety of genetic diseases and will provide invaluable models to study those diseases.


While this work is a huge accomplishment for science, there is still much work to be done before this technology can be used for the treatments of disease. First, the genes used to reprogram the skin cells into ES-like cells were added by the use of retroviruses that can cause mutations and lead to the risk of possible cancers, although recent research by professor Yamanaka's research group has made advances in avoiding this particular problem.[12]


In addition, as shown with the mouse work, one of the genes used to reprogram, Myc, can also cause cancer. The group led by Thomson did not use Myc to reprogram and may not have this difficulty. Future work is aimed at attempting to reprogram without permanent genetic manipulation of the cells with viruses. This could be accomplished by either small molecules or other methodologies to express these reprogramming genes.


However, as a first indication that the induced pluripotent stem (iPS) cell technology can in rapid succession lead to new cures, it was used by a research team headed by Rudolf Jaenisch of the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, to cure mice of sickle cell anemia, as reported by Science journal's online edition on 6th of December.[13] Rudolf Jaenisch (1942- ) is a German pioneer of transgenic science, in which an animal’s genetic makeup is altered. ... Founded in 1984, the Whitehead Institute for Biomedical Research is a non-profit research and teaching institution located in Cambridge, Massachusetts. ... This article is about the city in England. ... This article is about the U.S. state. ... Sickle-shaped red blood cells Sickle cell anemia (American English), sickle cell anaemia (British English) or sickle cell disease is a genetic disease in which red blood cells may change shape under certain circumstances. ... Science is the academic journal of the American Association for the Advancement of Science and is considered one of the worlds most prestigious scientific journals. ...


On January 16, 2008, a California based company, Stemagen, announced that they had created the first mature cloned human embryos from single skin cells taken from adults. These embryos can be harvested for patient matching embryonic stem cells.[14]


References

  1. ^ Department of Stem Cell Biology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto (August 25, 2006). "Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors". Cell. 
  2. ^ Andrews P, Matin M, Bahrami A, Damjanov I, Gokhale P, Draper J (2005). "Embryonic stem (ES) cells and embryonal carcinoma (EC) cells: opposite sides of the same coin.". Biochem Soc Trans 33 (Pt 6): 1526-30. PMID 16246161. 
  3. ^ Evans M, Kaufman M (1981). "Establishment in culture of pluripotential cells from mouse embryos.". Nature 292 (5819): 154-6. doi:10.1038/292154a0. PMID 7242681. 
  4. ^ Martin G (1981). "Isolation of a pluripotent cell line from early mouse embryos cultured in medium conditioned by teratocarcinoma stem cells.". Proc Natl Acad Sci U S A 78 (12): 7634-8. doi:10.1073/pnas.78.12.7634. PMID 6950406. 
  5. ^ Thomson J, Itskovitz-Eldor J, Shapiro S, Waknitz M, Swiergiel J, Marshall V, Jones J (1998). "Embryonic stem cell lines derived from human blastocysts.". Science 282 (5391): 1145-7. doi:10.1126/science.282.5391.1145. PMID 9804556. 
  6. ^ "Derivation of embryonic germ cells and male gametes from embryonic stem cells" (January 8, 2004). Nature 427: 148-154. doi:10.1038/nature02247. 
  7. ^ Access to articles : Nature Medicine
  8. ^ Lancet Medical Journal
  9. ^ Klimanskaya I, Chung Y, Becker S, Lu SJ, Lanza R. (2006). "Human embryonic stem cell lines derived from single blastomeres.". Nature 444 (7118): 481-5. PMID 16929302. 
  10. ^ "Human stem cells may be produced without embryos ‘within months’", Zangani, July 17, 2007. 
  11. ^ "Embryonic stem cells made without embryos", Reuters, November 21, 2007. 
  12. ^ "Researchers get closer to safe stem cell treatments", AFP, February 14, 2008. 
  13. ^ Rick Weiss. "Scientists Cure Mice Of Sickle Cell Using Stem Cell Technique: New Approach Is From Skin, Not Embryos", Washington Post, December 7, 2007, pp. A02. 
  14. ^ Helen Briggs. "US team makes embryo clone of men", BBC, January 17, 2008, pp. A01. 

Cell is a bi-monthly peer-reviewed scientific journal which publishes novel research in any area of experimental biology that is significant outside its field. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Nature is a prominent scientific journal, first published on 4 November 1869. ... A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Reuters Group plc (LSE: RTR and NASDAQ: RTRSY); pronounced is known as a financial market data provider and a news service that provides reports from around the world to newspapers and broadcasters. ... AFP is a three-letter acronym that may refer to: Advertiser funded programming Acute flaccid paralysis Active FoxPro Pages Advanced Flexible Processor, a model of Cyber computer by Control Data Corporation Advanced Function Presentation, an IBM printing architecture and file format Agence France-Presse, a major news agency Alpha-fetoprotein... The Washington Post is the largest newspaper in Washington, D.C.. It is also one of the citys oldest papers, having been founded in 1877. ... For other uses, see BBC (disambiguation). ...

External links

See also


  Results from FactBites:
 
ISSCR :: Public : Beyond the Basics : Selected Topics : Embryonic Stem Cells (787 words)
Human embryonic stem (ES) cells are cultured cell lines derived from the inner cell mass of the blastocyst that can be grown indefinitely in their undifferentiated state, yet also are capable of differentiating into all cells of the adult body.
Embryonic stem cell research is undertaken on cells derived from the inner cell mass (see image below) of blastocysts that have developed from fertilized eggs following in vitro fertilization.
Once embryonic stem cells have been established in culture, they can be propagated and even amplified for a long time, without loosing their true stem cell character and potential.
Stem cell - Wikipedia, the free encyclopedia (1291 words)
Embryonic stem cells are cultured pluripotent cells obtained from the undifferentiated inner mass cells of an early stage human embryo (sometimes called a blastocyst, which is an embryo that is between 50 to 150 cells).
Cancer stem cells arising through malignant transformation of adult stem cells are proposed to be the source of some or all tumors and cause metastasis and relapse of the disease.
Embryonic stem cell research is particularly controversial because, with the present state of technology, starting a stem cell 'line' requires the destruction of a human embryo and/or therapeutic cloning.
  More results at FactBites »

 
 

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