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Sample records for human embryo stem

  1. Sourcing human embryos for embryonic stem cell lines: Problems & perspectives

    OpenAIRE

    Mehta, Rajvi H.

    2014-01-01

    The ability to successfully derive human embryonic stem cells (hESC) lines from human embryos following in vitro fertilization (IVF) opened up a plethora of potential applications of this technique. These cell lines could have been successfully used to increase our understanding of human developmental biology, transplantation medicine and the emerging science of regenerative medicine. The main source for human embryos has been ′discarded′ or ′spare′ fresh or frozen human embryos following IVF...

  2. Sourcing human embryos for embryonic stem cell lines: Problems & perspectives

    Directory of Open Access Journals (Sweden)

    Rajvi H Mehta

    2014-01-01

    Full Text Available The ability to successfully derive human embryonic stem cells (hESC lines from human embryos following in vitro fertilization (IVF opened up a plethora of potential applications of this technique. These cell lines could have been successfully used to increase our understanding of human developmental biology, transplantation medicine and the emerging science of regenerative medicine. The main source for human embryos has been ′discarded′ or ′spare′ fresh or frozen human embryos following IVF. It is a common practice to stimulate the ovaries of women undergoing any of the assisted reproductive technologies (ART and retrieve multiple oocytes which subsequently lead to multiple embryos. Of these, only two or maximum of three embryos are transferred while the rest are cryopreserved as per the decision of the couple. In case a couple does not desire to ′cryopreserve′ their embryos then all the embryos remaining following embryo transfer can be considered ′spare′ or if a couple is no longer in need of the ′cryopreserved′ embryos then these also can be considered as ′spare′. But, the question raised by the ethicists is, "what about ′slightly′ over-stimulating a woman to get a few extra eggs and embryos? The decision becomes more difficult when it comes to ′discarded′ embryos. As of today, the quality of the embryos is primarily assessed based on morphology and the rate of development mainly judged by single point assessment. Despite many criteria described in the literature, the quality assessment is purely subjective. The question that arises is on the decision of ′discarding′ embryos. What would be the criteria for discarding embryos and the potential ′use′ of ESC derived from the ′abnormal appearing′ embryos? This paper discusses some of the newer methods to procure embryos for the derivation of embryonic stem cell lines which will respect the ethical concerns but still provide the source material.

  3. Sourcing human embryos for embryonic stem cell lines: problems & perspectives.

    Science.gov (United States)

    Mehta, Rajvi H

    2014-11-01

    The ability to successfully derive human embryonic stem cells (hESC) lines from human embryos following in vitro fertilization (IVF) opened up a plethora of potential applications of this technique. These cell lines could have been successfully used to increase our understanding of human developmental biology, transplantation medicine and the emerging science of regenerative medicine. The main source for human embryos has been 'discarded' or 'spare' fresh or frozen human embryos following IVF. It is a common practice to stimulate the ovaries of women undergoing any of the assisted reproductive technologies (ART) and retrieve multiple oocytes which subsequently lead to multiple embryos. Of these, only two or maximum of three embryos are transferred while the rest are cryopreserved as per the decision of the couple. in case a couple does not desire to 'cryopreserve' their embryos then all the embryos remaining following embryo transfer can be considered 'spare' or if a couple is no longer in need of the 'cryopreserved' embryos then these also can be considered as 'spare'. But, the question raised by the ethicists is, "what about 'slightly' over-stimulating a woman to get a few extra eggs and embryos? The decision becomes more difficult when it comes to 'discarded' embryos. As of today, the quality of the embryos is primarily assessed based on morphology and the rate of development mainly judged by single point assessment. Despite many criteria described in the literature, the quality assessment is purely subjective. The question that arises is on the decision of 'discarding' embryos. What would be the criteria for discarding embryos and the potential 'use' of ESC derived from the 'abnormal appearing' embryos? This paper discusses some of the newer methods to procure embryos for the derivation of embryonic stem cell lines which will respect the ethical concerns but still provide the source material.

  4. Derivation of Two New Human Embryonic Stem Cell Lines from Nonviable Human Embryos

    Directory of Open Access Journals (Sweden)

    Svetlana Gavrilov

    2011-01-01

    Full Text Available We report the derivation and characterization of two new human embryonic stem cells (hESC lines (CU1 and CU2 from embryos with an irreversible loss of integrated organismic function. In addition, we analyzed retrospective data of morphological progression from embryonic day (ED 5 to ED6 for 2480 embryos not suitable for clinical use to assess grading criteria indicative of loss of viability on ED5. Our analysis indicated that a large proportion of in vitro fertilization (IVF embryos not suitable for clinical use could be used for hESC derivation. Based on these combined findings, we propose that criteria commonly used in IVF clinics to determine optimal embryos for uterine transfer can be employed to predict the potential for hESC derivation from poor quality embryos without the destruction of vital human embryos.

  5. Donating embryos for human embryonic stem cell (hESC) research: a committee opinion.

    Science.gov (United States)

    2013-10-01

    hESC research is an ethically acceptable use of human embryos that are in excess of those needed to meet the fertility goals of patients. The ethical basis for this view and issues to be considered during the informed consent process for the donation of embryos are developed in this document. This report replaces the Committee's 2009 report, "Donating spare embryos for stem cell research" (Fertil Steril 2009;91:667-70).

  6. Improved Method for Ex Ovo-Cultivation of Developing Chicken Embryos for Human Stem Cell Xenografts

    Directory of Open Access Journals (Sweden)

    Timo Schomann

    2013-01-01

    Full Text Available The characterization of human stem cells for the usability in regenerative medicine is particularly based on investigations regarding their differentiation potential in vivo. In this regard, the chicken embryo model represents an ideal model organism. However, the access to the chicken embryo is only achievable by windowing the eggshell resulting in limited visibility and accessibility in subsequent experiments. On the contrary, ex ovo-culture systems avoid such negative side effects. Here, we present an improved ex ovo-cultivation method enabling the embryos to survive 13 days in vitro. Optimized cultivation of chicken embryos resulted in a normal development regarding their size and weight. Our ex ovo-approach closely resembles the development of chicken embryos in ovo, as demonstrated by properly developed nervous system, bones, and cartilage at expected time points. Finally, we investigated the usability of our method for trans-species transplantation of adult stem cells by injecting human neural crest-derived stem cells into late Hamburger and Hamilton stages (HH26–HH28/E5—E6 of ex ovo-incubated embryos. We demonstrated the integration of human cells allowing experimentally easy investigation of the differentiation potential in the proper developmental context. Taken together, this ex ovo-method supports the prolonged cultivation of properly developing chicken embryos enabling integration studies of xenografted mammalian stem cells at late developmental stages.

  7. Fresh or frozen? Classifying 'spare' embryos for donation to human embryonic stem cell research.

    Science.gov (United States)

    Ehrich, Kathryn; Williams, Clare; Farsides, Bobbie

    2010-12-01

    United Kingdom (UK) funding to build human embryonic stem cell (hESC) derivation labs within assisted conception units (ACU) was intended to facilitate the 'In-vitro fertilisation (IVF)-stem cell interface', including the flow of fresh 'spare' embryos to stem cell labs. However, in the three sites reported on here, which received this funding, most of the embryos used for hESC research came from long term cryopreservation storage and/or outside clinics. In this paper we explore some of the clinical, technical, social and ethical factors that might help to explain this situation. We report from our qualitative study of the ethical frameworks for approaching women/couples for donation of embryos to stem cell research. Members of staff took part in 44 interviews and six ethics discussion groups held at our study sites between February 2008 and October 2009. We focus here on their articulations of social and ethical, as well as scientific, dimensions in the contingent classification of 'spare' embryos, entailing uncertainty, fluidity and naturalisation in classifying work. Social and ethical factors include acknowledging and responding to uncertainty in classifying embryos; retaining 'fluidity' in the grading system to give embryos 'every chance'; tensions between standardisation and variation in enacting a 'fair' grading system; enhancement of patient choice and control, and prevention of regret; and incorporation of patients' values in construction of ethically acceptable embryo 'spareness' ('frozen' embryos, and embryos determined through preimplantation genetic diagnosis (PGD) to be genetically 'affected'). We argue that the success of the 'built moral environment' of ACU with adjoining stem cell laboratories building projects intended to facilitate the 'IVF-stem cell interface' may depend not only on architecture, but also on the part such social and ethical factors play in configuration of embryos as particular kinds of moral work objects.

  8. Abnormalities in centrosome number in human embryos and embryonic stem cells.

    Science.gov (United States)

    Gu, Yi-Fan; OuYang, Qi; Dai, Can; Lu, Chang-Fu; Lin, Ge; Gong, Fei; Lu, Guang-Xiu

    2016-05-01

    Chromosomal abnormalities are common in human embryos. Previous studies have suggested links between centrosome number and chromosome abnormalities, but information regarding abnormalities in centrosome number in human embryos is limited. We analyzed abnormalities in centrosome number in human embryos and embryonic stem cells (hESCs). Following normal fertilization, supernumerary centrosomes were present at rates of 7.3% in two-pronucleus (2PN)-stage zygotes and 6.5% in first-cleavage zygotes. Supernumerary centrosomes were also detected in 24.4% of blastomeres from 60% of embryos derived from 2PN zygotes. Conversely, in mono- (1PN) and tri-pronucleus (3PN) zygotes, the frequency of abnormal centrosome number increased substantially at first cleavage. Rates in blastomeres of Day-3 embryos, however, were about the same between embryos derived from 1PN and 2PN zygotes, whereas abnormalities in centrosome number were higher in those from 3PN zygotes. By comparison, the rate of abnormal centrosome numbers in hESCs was 1.5-11.2%. Thus, abnormalities in centrosome number existed in human zygotes and cleaved embryos-especially those resulting from aberrant fertilization-but the frequency of such abnormalities was lower in hESCs derived from these embryos. These findings identify a source of the chromosomal instability in human embryos and hESCs, and highlight new safety issues for human assisted reproductive technology. Mol. Reprod. Dev. 83: 392-404, 2016. © 2016 Wiley Periodicals, Inc.

  9. Ethical questions concerning research on human embryos, embryonic stem cells and chimeras.

    Science.gov (United States)

    Bobbert, Monika

    2006-12-01

    Research using human embryos and embryonic stem cells is viewed as important for various reasons. Apart from questions concerning legal regulations, numerous ethical objections are raised pertaining to the use of surplus embryos from reproductive medicine as well as the creation of embryos and stem cells through cloning. In the hopes of avoiding ethical problems, alternatives have been proposed including the extraction of egg cells from "dead" embryos derived from in vitro fertilization procedures, the extraction of pluripotent stem cells from blastocysts, technologies such as "altered nuclear transfer" (ANT) and "oocyte-assisted reprogramming" (ANT-OAR) as well as parthenogenesis. Initial ethical assessments show that certain questions pertaining to such strategies have remained unanswered. Furthermore, with the help of new or more differentiated biotechnological procedures, it is possible to create chimeras and hybrids in which human and non-human cells are combined. Human-animal chimeras, in which gametes or embryonic tissue have been mixed with embryonic or adult stem cells, demonstrate a different "quality" and "degree of penetration" from those produced in previous experiments. Not only does this have consequences regarding questions of patentability, this situation also raises fundamental questions concerning the human being's self image, the concept of person, identity and species and the moral rights and duties that are connected with such concepts. There is a need for legal regulation, on the national as well as the international level.

  10. No relationship between embryo morphology and successful derivation of human embryonic stem cell lines.

    Directory of Open Access Journals (Sweden)

    Susanne Ström

    Full Text Available BACKGROUND: The large number (30 of permanent human embryonic stem cell (hESC lines and additional 29 which did not continue growing, in our laboratory at Karolinska Institutet have given us a possibility to analyse the relationship between embryo morphology and the success of derivation of hESC lines. The derivation method has been improved during the period 2002-2009, towards fewer xeno-components. Embryo quality is important as regards the likelihood of pregnancy, but there is little information regarding likelihood of stem cell derivation. METHODS: We evaluated the relationship of pronuclear zygote stage, the score based on embryo morphology and developmental rate at cleavage state, and the morphology of the blastocyst at the time of donation to stem cell research, to see how they correlated to successful establishment of new hESC lines. RESULTS: Derivation of hESC lines succeeded from poor quality and good quality embryos in the same extent. In several blastocysts, no real inner cell mass (ICM was seen, but permanent well growing hESC lines could be established. One tripronuclear (3PN zygote, which developed to blastocyst stage, gave origin to a karyotypically normal hESC line. CONCLUSION: Even very poor quality embryos with few cells in the ICM can give origin to hESC lines.

  11. Xenotransplantation of human adipose-derived stem cells in zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    Jin Li

    Full Text Available Zebrafish is a widely used animal model with well-characterized background in developmental biology. The fate of human adipose-derived stem cells (ADSCs after their xenotransplantation into the developing embryos of zebrafish is unknown. Therefore, human ADSCs were firstly isolated, and then transduced with lentiviral vector system carrying a green fluorescent protein (GFP reporter gene, and followed by detection of their cell viability and the expression of cell surface antigens. These GFP-expressing human ADSCs were transplanted into the zebrafish embryos at 3.3-4.3 hour post-fertilization (hpf. Green fluorescent signal, the proliferation and differentiation of human ADSCs in recipient embryos were respectively examined using fluorescent microscopy and immunohistochemical staining. The results indicated that human ADSCs did not change their cell viability and the expression levels of cell surface antigens after GFP transduction. Microscopic examination demonstrated that green fluorescent signals of GFP expressed in the transplanted cells were observed in the embryos and larva fish at post-transplantation. The positive staining of Ki-67 revealed the survival and proliferation of human ADSCs in fish larvae after transplantation. The expression of CD105 was observable in the xenotransplanted ADSCs, but CD31 expression was undetectable. Therefore, our results indicate that human ADSCs xenotransplanted in the zebrafish embryos not only can survive and proliferate at across-species circumstance, but also seem to maintain their undifferentiation status in a short term. This xenograft model of zebrafish embryos may provide a promising and useful technical platform for the investigation of biology and physiology of stem cells in vivo.

  12. Xenotransplantation of human adipose-derived stem cells in zebrafish embryos.

    Science.gov (United States)

    Li, Jin; Zeng, Guofang; Qi, Yawei; Tang, Xudong; Zhang, Jingjing; Wu, Zeyong; Liang, Jie; Shi, Lei; Liu, Hongwei; Zhang, Peihua

    2015-01-01

    Zebrafish is a widely used animal model with well-characterized background in developmental biology. The fate of human adipose-derived stem cells (ADSCs) after their xenotransplantation into the developing embryos of zebrafish is unknown. Therefore, human ADSCs were firstly isolated, and then transduced with lentiviral vector system carrying a green fluorescent protein (GFP) reporter gene, and followed by detection of their cell viability and the expression of cell surface antigens. These GFP-expressing human ADSCs were transplanted into the zebrafish embryos at 3.3-4.3 hour post-fertilization (hpf). Green fluorescent signal, the proliferation and differentiation of human ADSCs in recipient embryos were respectively examined using fluorescent microscopy and immunohistochemical staining. The results indicated that human ADSCs did not change their cell viability and the expression levels of cell surface antigens after GFP transduction. Microscopic examination demonstrated that green fluorescent signals of GFP expressed in the transplanted cells were observed in the embryos and larva fish at post-transplantation. The positive staining of Ki-67 revealed the survival and proliferation of human ADSCs in fish larvae after transplantation. The expression of CD105 was observable in the xenotransplanted ADSCs, but CD31 expression was undetectable. Therefore, our results indicate that human ADSCs xenotransplanted in the zebrafish embryos not only can survive and proliferate at across-species circumstance, but also seem to maintain their undifferentiation status in a short term. This xenograft model of zebrafish embryos may provide a promising and useful technical platform for the investigation of biology and physiology of stem cells in vivo.

  13. Brain stem global gene expression profiles in human spina bifida embryos

    Institute of Scientific and Technical Information of China (English)

    Hong Zhao; Xiang Li; Wan-I Lie; Quanren He; Ting Zhang; Xiaoying Zheng; Ran Zhou; Jun Xie

    2011-01-01

    Environmental and genetic factors influence the occurrence of neural tube defects, such as spina bifida.Specific disease expression patterns will help to elucidate the pathogenesis of disease.However, results obtained from animal models, which often exhibit organism specificity, do not fully explain the mechanisms of human spina bifida onset.In the present study, three embryos with a gestational age of approximately 17 weeks and a confirmed diagnosis of spina bifida, as well as 3 age-matched normal embryos, were obtained from abortions.Fetal brain stem tissues were dissected for RNA isolation, and microarray analyses were conducted to examine profiles of gene expression in brain stems of spina bifida and normal embryos using Affymetrix HG-U1 33A 2.0 GeneChip arrays.Of the 14 500 gene transcripts examined, a total of 182 genes exhibited at least 2.5-fold change in expression, including 140 upregulated and 42 downregulated genes.These genes were placed into 19 main functional categories according to the Gene Ontology Consortium database for biological functions.Of the 182 altered genes, approximately 50% were involved in cellular apoptosis, growth, adhesion, cell cycle, stress, DNA replication and repair, signal transduction, nervous system development, oxidoreduction, immune responses, and regulation of gene transcription.Gene expression in multiple biological pathways was altered in the brain stem of human spina bifida embryos.

  14. Use of "excess" human embryos for stem cell research: protecting women's rights and health.

    Science.gov (United States)

    Cohen, C B

    2000-01-01

    Proposed National Institutes of Health guidelines for stem cell research are too narrowly drawn and do not adequately protect the freedom of choice and health of women who donate embryos. They need to be expanded to cover not only the point of embryo donation, but also that of embryo creation. Guidelines are provided to ensure that donors undergoing hyperstimulation and egg retrieval gave voluntary informed consent to the production of embryos that might later prove in excess. A standard for determining when embryos have been overproduced is presented to address the possibility that additional embryos will be created for stem cell research in violation of the guidelines and at risk to women's health.

  15. Admixed human embryos and stem cells: legislative, ethical and scientific advances.

    Science.gov (United States)

    Bahadur, G; Iqbal, M; Malik, S; Sanyal, A; Wafa, R; Noble, R

    2008-01-01

    This paper examines the regulatory framework currently governing the creation of animal-human hybrids and chimera embryos in stem cell research, and some of the ethical implications of such research. It discusses the findings of a recent government select committee that considered the topic. It considers the debate around the precise definition of a human embryo, and whether such hybrids therefore fall within the remit of the Human Fertilisation and Embryology Authority. It outlines the advantages of such hybrids, in lessening the need for human egg donors, as well as the moral objections to species boundary violation. It calls for an examination of the scientific benefits of such research to inform debate on the question, and argues for the need to take genuine account of the public's views on this matter.

  16. Human amniotic epithelial cells as feeder layer to derive and maintain human embryonic stem cells from poor-quality embryos.

    Science.gov (United States)

    Ávila-González, Daniela; Vega-Hernández, Eva; Regalado-Hernández, Juan Carlos; De la Jara-Díaz, Julio Francisco; García-Castro, Irma Lydia; Molina-Hernández, Anayansi; Moreno-Verduzco, Elsa Romelia; Razo-Aguilera, Guadalupe; Flores-Herrera, Héctor; Portillo, Wendy; Díaz-Martínez, Néstor Emmanuel; García-López, Guadalupe; Díaz, Néstor Fabián

    2015-09-01

    Data from the literature suggest that human embryonic stem cell (hESC) lines used in research do not genetically represent all human populations. The derivation of hESC through conventional methods involve the destruction of viable human embryos, as well the use of mouse embryonic fibroblasts as a feeder layer, which has several drawbacks. We obtained the hESC line (Amicqui-1) from poor-quality (PQ) embryos derived and maintained on human amniotic epithelial cells (hAEC). This line displays a battery of markers of pluripotency and we demonstrated the capacity of these cells to produce derivates of the three germ layers.

  17. Human amniotic epithelial cells as feeder layer to derive and maintain human embryonic stem cells from poor-quality embryos

    Directory of Open Access Journals (Sweden)

    Daniela Ávila-González

    2015-09-01

    Full Text Available Data from the literature suggest that human embryonic stem cell (hESC lines used in research do not genetically represent all human populations. The derivation of hESC through conventional methods involve the destruction of viable human embryos, as well the use of mouse embryonic fibroblasts as a feeder layer, which has several drawbacks. We obtained the hESC line (Amicqui-1 from poor-quality (PQ embryos derived and maintained on human amniotic epithelial cells (hAEC. This line displays a battery of markers of pluripotency and we demonstrated the capacity of these cells to produce derivates of the three germ layers.

  18. Ethical consideration of experimentation using living human embryos: the Catholic Church's position on human embryonic stem cell research and human cloning.

    Science.gov (United States)

    Ohara, N

    2003-01-01

    Although the potential applications of human embryonic stem cells and therapeutic cloning hold promise for the alleged medical benefits, these technologies have posed profound ethical issues because they necessitate the destruction of human embryos. A fundamental point in the issues is the concept of the moral status of human embryos. The Catholic Church has held that human life begins at the moment of conception and therefore, has defended the dignity, inviolable right to life and integrity of human embryos. The Catholic Church has opposed human embryonic stem cell research and any kind of human cloning because they are contrary to the dignity of procreation, of conjugal union and of human embryos. Moreover, these techniques have the risk of creating a sub-category of human beings that are destined basically for the convenience of others. In conclusion, science and technology can never be independent of the criterion of morality, since technology exists for man and must respect his finality.

  19. The influence of early embryo traits on human embryonic stem cell derivation efficiency.

    Science.gov (United States)

    O'Leary, Thomas; Heindryckx, Björn; Lierman, Sylvie; Van der Jeught, Margot; Menten, Björn; Deforce, Dieter; Cornelissen, Ria; de Sousa Lopes, Susana Chuva; De Sutter, Petra

    2011-05-01

    Despite its prognostic value in in vitro fertilization, early embryo morphology is not reported on in the derivation of human embryonic stem cell (hESC) lines. Standard hESC derivation does rely on blastocyst development and its efficiency is highly correlated to inner cell mass (ICM) quality. Poor-quality embryos (PQEs) donated for hESC derivation may have a range of cleavage-stage abnormalities that are known to compromise further development. This study was implemented to determine whether specific PQEs traits influence the efficiency of good-quality ICMs to derive new hESC lines. We found that although the types of PQEs investigated were all able to make blastocysts with good-quality ICMs, the ICMs were unequal in their ability to derive hESCs. Good-quality ICMs from embryos with multiple poor-quality traits were unable to generate hESC lines, in contrast to good-quality ICMs from embryos with a single poor-quality trait. In addition, our data suggest a direct correlation between the number of ICM cells present in the blastocyst and its capacity to derive new hESC lines. This study is the first to demonstrate that ICM quality alone is an incomplete indicator of hESC derivation and that application of in vitro fertilization-based early embryo scoring can help predict hESC derivation efficiency. Experiments aiming to quantify, improve upon, or compare hESC derivation efficiency should thus take into consideration early embryo morphology scoring for the comparison of groups with equal developmental competence.

  20. In vitro fertilization and stem cell harvesting from human embryos: the law and practice in the United States.

    Science.gov (United States)

    Hook, C Christopher

    2010-07-01

    The challenges before science and medicine are these: science must explore the natural world as thoroughly as possible, while still honoring, protecting, serving and preserving the subject of its investigations, and the human beings for whom it is a tool; medicine must confront disease and disability as effectively as possible, while also honoring, protecting, and preserving those beings for whom it serves - all of those beings, not just some, or even most, at the potential expense of others. These goals are challenged by embryo-destructive human embryonic stem cell research. The human embryo is a human being as clearly defined by embryology, and as such should be protected by the codes governing human subject research. However, because of the "potential" benefits offered by pluripotent stem cells, coupled with abortion politics and a very poorly regulated infertility industry, United States governmental advisory commissions and the scientific, medical, and political communities have attempted to define away the humanity of the human embryo, with a few notable exceptions. Because infertility treatments in the United States are poorly regulated, there are large numbers of supernumerary embryos in cryopreservation. However, only a tiny portion of these will ever be potentially available for research, and thus are not a realistic source of the cells necessary to provide treatments to the millions who might benefit from proposed stem cell based therapies. Cloning will not be the answer either, given the millions of women who must be exploited to provide sufficient numbers of eggs to generate the cloned cell lines. Moreover, the disposition decisions parents must make for their extra embryos are often agonizing, and not uncommonly change. The use of supernumerary embryos as a source for human embryonic stem cells is unethical, will never be a sufficient source for the medical treatments expected from stem cell research, and is often a source of great distress for the

  1. In vitro fertilization and stem cell harvesting from human embryos: the law and practice in the United States

    Directory of Open Access Journals (Sweden)

    C. Christopher Hook

    2010-07-01

    Full Text Available The challenges before science and medicine are these: science must explore the natural world as thoroughly as possible, while still honoring, protecting, serving and preserving the subject of its investigations, and the human beings for whom it is a tool; medicine must confront disease and disability as effectively as possible, while also honoring, protecting, and preserving those beings for whom it serves – all of those beings, not just some, or even most, at the potential expense of others. These goals are challenged by embryo-destructive human embryonic stem cell research. The human embryo is a human being as clearly defined by embryology, and as such should be protected by the codes governing human subject research. However, because of the “potential” benefits offered by pluripotent stem cells, coupled with abortion politics and a very poorly regulated infertility industry, United States governmental advisory commissions and the scientific, medical, and political communities have attempted to define away the humanity of the human embryo, witha few notable exceptions. Because infertility treatments in the United States are poorly regulated, there are large numbersof supernumerary embryos in cryopreservation. However, only a tiny portion of these will ever be potentially available for research, and thus are not a realistic source of the cells necessary to provide treatments to the millions who might benefit from proposed stem cell based therapies. Cloning willnot be the answer either, given the millions of women who must be exploited to provide sufficient numbers of eggs to generate the cloned cell lines. Moreover, the disposition decisions parents must make for their extra embryos are often agonizing, and not uncommonly change.The use of supernumerary embryos as a source for human embryonic stem cells is unethical, will never be a sufficient source for the medical treatments expected from stem cell research, and is often a source of

  2. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research.

    Science.gov (United States)

    Manninen, Bertha Alvarez

    2008-01-31

    One argument used by detractors of human embryonic stem cell research (hESCR) invokes Kant's formula of humanity, which proscribes treating persons solely as a means to an end, rather than as ends in themselves. According to Fuat S. Oduncu, for example, adhering to this imperative entails that human embryos should not be disaggregated to obtain pluripotent stem cells for hESCR. Given that human embryos are Kantian persons from the time of their conception, killing them to obtain their cells for research fails to treat them as ends in themselves. This argument assumes two points that are rather contentious given a Kantian framework. First, the argument assumes that when Kant maintains that humanity must be treated as an end in itself, he means to argue that all members of the species Homo sapiens must be treated as ends in themselves; that is, that Kant regards personhood as co-extensive with belonging to the species Homo sapiens. Second, the argument assumes that the event of conception is causally responsible for the genesis of a Kantian person and that, therefore, an embryo is a Kantian person from the time of its conception. In this paper, I will present challenges against these two assumptions by engaging in an exegetical study of some of Kant's works. First, I will illustrate that Kant did not use the term "humanity" to denote a biological species, but rather the capacity to set ends according to reason. Second, I will illustrate that it is difficult given a Kantian framework to denote conception (indeed any biological event) as causally responsible for the creation of a person. Kant ascribed to a dualistic view of human agency, and personhood, according to him, was derived from the supersensible capacity for reason. To argue that a Kantian person is generated due to the event of conception ignores Kant's insistence in various aspects of his work that it is not possible to understand the generation of a person qua a physical operation. Finally, I will end the

  3. Are human embryos Kantian persons?: Kantian considerations in favor of embryonic stem cell research

    Directory of Open Access Journals (Sweden)

    Manninen Bertha

    2008-01-01

    Full Text Available Abstract One argument used by detractors of human embryonic stem cell research (hESCR invokes Kant's formula of humanity, which proscribes treating persons solely as a means to an end, rather than as ends in themselves. According to Fuat S. Oduncu, for example, adhering to this imperative entails that human embryos should not be disaggregated to obtain pluripotent stem cells for hESCR. Given that human embryos are Kantian persons from the time of their conception, killing them to obtain their cells for research fails to treat them as ends in themselves. This argument assumes two points that are rather contentious given a Kantian framework. First, the argument assumes that when Kant maintains that humanity must be treated as an end in itself, he means to argue that all members of the species Homo sapiens must be treated as ends in themselves; that is, that Kant regards personhood as co-extensive with belonging to the species Homo sapiens. Second, the argument assumes that the event of conception is causally responsible for the genesis of a Kantian person and that, therefore, an embryo is a Kantian person from the time of its conception. In this paper, I will present challenges against these two assumptions by engaging in an exegetical study of some of Kant's works. First, I will illustrate that Kant did not use the term "humanity" to denote a biological species, but rather the capacity to set ends according to reason. Second, I will illustrate that it is difficult given a Kantian framework to denote conception (indeed any biological event as causally responsible for the creation of a person. Kant ascribed to a dualistic view of human agency, and personhood, according to him, was derived from the supersensible capacity for reason. To argue that a Kantian person is generated due to the event of conception ignores Kant's insistence in various aspects of his work that it is not possible to understand the generation of a person qua a physical

  4. Clinically failed eggs as a source of normal human embryo stem cells.

    Science.gov (United States)

    De Sousa, Paul A; Gardner, John; Sneddon, Sharon; Pells, Steve; Tye, Britt Jorgensen; Dand, Pawlina; Collins, Daniel M; Stewart, Karen; Shaw, Lisa; Przyborski, Stefan; Cooke, Michael; McLaughlin, K John; Kimber, Susan J; Lieberman, Brian A; Wilmut, Ian; Brison, Daniel R

    2009-05-01

    The promise of human embryo stem cells (hESCs) for regenerative medicine is offset by the ethical and practical challenges involved in sourcing eggs and embryos for this objective. In this study we sought to isolate an hESC line from clinically failed eggs, the usage of which would not conflict with donor interests to conceive. A total of 8 blastocysts were allocated for hESC derivation from a pool of 579 eggs whose fertilization had been clinically assessed to have occurred abnormally (i.e., three pronuclei) or failed (i.e., no pronuclei) following in vitro insemination or intracytoplasmic sperm injection (ICSI). The latter were subjected to a recovery intervention consisting of either reinsemination by ICSI or parthenogenetic stimulation. One hESC line (RCM1) was obtained from a failed-to-fertilize inseminated egg recovered by parthenogenetic activation. Standard in vitro and in vivo characterization revealed this line to possess all of the properties attributed to a normal euploid hESC line. Whole-genome single-nucleotide polymorphism analysis further revealed that the line was biparental, indicating that sperm penetration had occurred, although parthenogenetic stimulation was required for activation. Our results demonstrate the viability of an alternative strategy to generate normal hESC lines from clinically failed eggs, thereby further minimizing the potential to conflict with donor reproductive interest to conceive.

  5. Ethical and policy issues surrounding the donation of cryopreserved and fresh embryos for human embryonic stem cell research.

    Science.gov (United States)

    Cohen, Cynthia B

    2009-06-01

    The use of human embryos in human embryonic stem cell (hESC) research raises significant ethical and policy issues associated with their donation. Recent research conducted in several countries assesses the percent of persons with cryopreserved and fresh supernumerary embryos willing to donate them for research, their reasons for considering this option, and the concerns they raise about its personal import. Such research provides new insights into rising ethical and policy questions associated with embryo donation for hESC research that should be addressed. In response to such questions, it is argued here that consent to the donation of supernumerary embryos for hESC research should be sought in two or three stages, depending on whether fresh or frozen embryos are at issue, in order to provide patients and their partners with sufficient time and information before they make a final decision. In addition, steps should be taken to support the voluntariness of their decisions by having personnel other than the treating reproductive specialist or stem cell investigators solicit their consent. Prospective embryo donors should also be given a choice about the uses to which hESCs derived from their donated embryos will be put in order to honor their ethical convictions and ensure that there are sufficient embryos for this research. The well-being and rights of those who donate embryos for this research require the sort of support and protection that can be provided by an ethical and policy framework that allows hESC investigations to move forward according to standards that are transparent and that resound with public values.

  6. Scientists Create Part-Human, Part-Pig Embryo

    Science.gov (United States)

    ... 163262.html Scientists Create Part-Human, Part-Pig Embryo One goal of this stem cell research is ... have successfully used human stem cells to create embryos that are part-human, part-pig. Scientists said ...

  7. Beyond the 'embryo question': human embryonic stem cell ethics in the context of biomaterial donation in the UK.

    Science.gov (United States)

    Bahadur, G; Morrison, M; Machin, L

    2010-12-01

    Discussion about the ethics of human embryonic stem cell (ESC) research in the UK tends to be dominated by the divisive and potentially intractable issue of the moral status of the embryo. This can have the effect of silencing or marginalizing other concerns, especially in the context of public engagement with science in this field. One such area of potential public concern is the donation of oocytes and embryos to stem cell research. Contemporary research on the views of donors and potential donors about a wide range of biomaterials, from solid organs to gametes and bone marrow, is reviewed and used to illustrate the range and types of ethical concerns articulated by this important group of stakeholders. Attitudes to donation are found to vary according to the type of tissue being donated or collected, the purpose for which donation is being sought and the nature of the recipient of the donation. Pertinently, attitudes towards donating oocytes are found to differ in some respects from donation of embryos or fetal tissue. The implications of these findings for ensuring ethically robust informed consent and publicly acceptable sourcing of human biomaterials for stem cell research are then considered.

  8. Effect of human adipose tissue-derived mesenchymal-stem-cell bioactive materials on porcine embryo development.

    Science.gov (United States)

    Park, Hyo-Young; Kim, Eun-Young; Lee, Seung-Eun; Choi, Hyun-Yong; Moon, Jeremiah Jiman; Park, Min-Jee; Son, Yeo-Jin; Lee, Jun-Beom; Jeong, Chang-Jin; Lee, Dong-Sun; Riu, Key-Jung; Park, Se-Pill

    2013-12-01

    Human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) secrete bioactive materials that are beneficial for tissue repair and regeneration. In this study, we characterized human hAT-MSC bioactive material (hAT-MSC-BM), and examined the effect of hAT-MSC-BM on porcine embryo development. hAT-MSC-BM was enriched with several growth factors and cytokines, including fibroblast growth factor 2 (FGF2), vascular endothelial growth factor A (VEGFA), and interleukin 6 (IL6). Among the various concentrations and days of treatment tested, 10% hAT-MSC-BM treatment beginning on culture Day 4 provided the best environment for the in vitro growth of parthenogenetic porcine embryos. While the addition of 10% fetal bovine serum (FBS) increased the hatching rate and the total cell number of parthenogenetic porcine embryos compared with the control and hAT-MSC culture medium group, the best results were from the group cultured with 10% hAT-MSC-BM. Mitochondrial activity was also higher in the 10% hAT-MSC-BM-treated group. Moreover, the relative mRNA expression levels of development and anti-apoptosis genes were significantly higher in the 10% hAT-MSC-BM-treated group than in control, hAT-MSC culture medium, or 10% FBS groups, whereas the transcript abundance of an apoptosis gene was slightly lower. Treatment with 10% hAT-MSC-BM starting on Day 4 also improved the development rate and the total cell number of in vitro-fertilized embryos. This is the first report on the benefits of hAT-MSC-BM in a porcine embryo in vitro culture system. We conclude that hAT-MSC-BM is a new, alternative supplement that can improve the development of porcine embryos during both parthenogenesis and fertilization in vitro.

  9. Single-Cell XIST Expression in Human Preimplantation Embryos and Newly Reprogrammed Female Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Briggs, Sharon F; Dominguez, Antonia A; Chavez, Shawn L; Reijo Pera, Renee A

    2015-06-01

    The process of X chromosome inactivation (XCI) during reprogramming to produce human induced pluripotent stem cells (iPSCs), as well as during the extensive programming that occurs in human preimplantation development, is not well-understood. Indeed, studies of XCI during reprogramming to iPSCs report cells with two active X chromosomes and/or cells with one inactive X chromosome. Here, we examine expression of the long noncoding RNA, XIST, in single cells of human embryos through the oocyte-to-embryo transition and in new mRNA reprogrammed iPSCs. We show that XIST is first expressed beginning at the 4-cell stage, coincident with the onset of embryonic genome activation in an asynchronous manner. Additionally, we report that mRNA reprogramming produces iPSCs that initially express XIST transcript; however, expression is rapidly lost with culture. Loss of XIST and H3K27me3 enrichment at the inactive X chromosome at late passage results in X chromosome expression changes. Our data may contribute to applications in disease modeling and potential translational applications of female stem cells.

  10. Pavia symposium on embryos and stem cells

    Directory of Open Access Journals (Sweden)

    M Boiani

    2009-08-01

    Full Text Available Stem cells occur in very small numbers in adult tissues, in higher numbers in the fetus and its annexes and they can be derived from whole embryos or parts thereof. For a couple of years, stem cells can also be derived straight from somatic cells by retrovirus-mediated transfer of selected genes in culture. Stem cells have varying capacities for self-renewal and differentiation according to their origin, up to the point that they can be propagated in vitro for years and give rise to a wide range of cell types. This makes them suitable means for cell and tissue-replacement therapies. Gaining access to stem cells involves manipulation of living organisms i.e. human beings or animal models. The extent of manipulation ranges from the mere biopsy and culture of body cells in vitro, to their genetic manipulation and back-grafting in vivo.This raises bioethical issues as to whether we should manipulate animal and in particular human life. Many scientific meetings have been organized to present research findings on stem cells and on their potency, differentiation and therapeutic applications for treating disease. In many of these meetings, the ‘mother’ of all stem cells - the embryo - has often been ignored, because embryonic stem cells do not exist as such in the embryo and because the manipulation of the embryo brings up ethical concerns.To make up for this omission, the theme of our meeting was ‘Pluripotency and differentiation in embryos and stem cells’.With a strong sense of purpose and commitment, we managed to hold a two-day symposium concerned with three major topics: 1 natural and induced pluripotency; 2 mechanisms of cell fate control; 3 adult and cancer stem cells. The meeting took place on January 17th-18th 2008 in the beautiful, frescoed halls of Collegio Ghislieri and Borromeo, two foremost colleges in the Pavia campus. A small but prominent group of scientists took part in the meeting – James Adjaye (Germany, Anne Grete Byskov

  11. Microarray Analyses Reveal Marked Differences in Growth Factor and Receptor Expression Between 8-Cell Human Embryos and Pluripotent Stem Cells.

    Science.gov (United States)

    Vlismas, Antonis; Bletsa, Ritsa; Mavrogianni, Despina; Mamali, Georgina; Pergamali, Maria; Dinopoulou, Vasiliki; Partsinevelos, George; Drakakis, Peter; Loutradis, Dimitris; Kiessling, Ann A

    2016-01-15

    Previous microarray analyses of RNAs from 8-cell (8C) human embryos revealed a lack of cell cycle checkpoints and overexpression of core circadian oscillators and cell cycle drivers relative to pluripotent human stem cells [human embryonic stem cells/induced pluripotent stem (hES/iPS)] and fibroblasts, suggesting growth factor independence during early cleavage stages. To explore this possibility, we queried our combined microarray database for expression of 487 growth factors and receptors. Fifty-one gene elements were overdetected on the 8C arrays relative to hES/iPS cells, including 14 detected at least 80-fold higher, which annotated to multiple pathways: six cytokine family (CSF1R, IL2RG, IL3RA, IL4, IL17B, IL23R), four transforming growth factor beta (TGFB) family (BMP6, BMP15, GDF9, ENG), one fibroblast growth factor (FGF) family [FGF14(FH4)], one epidermal growth factor member (GAB1), plus CD36, and CLEC10A. 8C-specific gene elements were enriched (73%) for reported circadian-controlled genes in mouse tissues. High-level detection of CSF1R, ENG, IL23R, and IL3RA specifically on the 8C arrays suggests the embryo plays an active role in blocking immune rejection and is poised for trophectoderm development; robust detection of NRG1, GAB1, -2, GRB7, and FGF14(FHF4) indicates novel roles in early development in addition to their known roles in later development. Forty-four gene elements were underdetected on the 8C arrays, including 11 at least 80-fold under the pluripotent cells: two cytokines (IFITM1, TNFRSF8), five TGFBs (BMP7, LEFTY1, LEFTY2, TDGF1, TDGF3), two FGFs (FGF2, FGF receptor 1), plus ING5, and WNT6. The microarray detection patterns suggest that hES/iPS cells exhibit suppressed circadian competence, underexpression of early differentiation markers, and more robust expression of generic pluripotency genes, in keeping with an artificial state of continual uncommitted cell division. In contrast, gene expression patterns of the 8C embryo suggest that

  12. Microarray Analyses Reveal Marked Differences in Growth Factor and Receptor Expression Between 8-Cell Human Embryos and Pluripotent Stem Cells

    Science.gov (United States)

    Vlismas, Antonis; Bletsa, Ritsa; Mavrogianni, Despina; Mamali, Georgina; Pergamali, Maria; Dinopoulou, Vasiliki; Partsinevelos, George; Drakakis, Peter; Loutradis, Dimitris

    2016-01-01

    Previous microarray analyses of RNAs from 8-cell (8C) human embryos revealed a lack of cell cycle checkpoints and overexpression of core circadian oscillators and cell cycle drivers relative to pluripotent human stem cells [human embryonic stem cells/induced pluripotent stem (hES/iPS)] and fibroblasts, suggesting growth factor independence during early cleavage stages. To explore this possibility, we queried our combined microarray database for expression of 487 growth factors and receptors. Fifty-one gene elements were overdetected on the 8C arrays relative to hES/iPS cells, including 14 detected at least 80-fold higher, which annotated to multiple pathways: six cytokine family (CSF1R, IL2RG, IL3RA, IL4, IL17B, IL23R), four transforming growth factor beta (TGFB) family (BMP6, BMP15, GDF9, ENG), one fibroblast growth factor (FGF) family [FGF14(FH4)], one epidermal growth factor member (GAB1), plus CD36, and CLEC10A. 8C-specific gene elements were enriched (73%) for reported circadian-controlled genes in mouse tissues. High-level detection of CSF1R, ENG, IL23R, and IL3RA specifically on the 8C arrays suggests the embryo plays an active role in blocking immune rejection and is poised for trophectoderm development; robust detection of NRG1, GAB1, -2, GRB7, and FGF14(FHF4) indicates novel roles in early development in addition to their known roles in later development. Forty-four gene elements were underdetected on the 8C arrays, including 11 at least 80-fold under the pluripotent cells: two cytokines (IFITM1, TNFRSF8), five TGFBs (BMP7, LEFTY1, LEFTY2, TDGF1, TDGF3), two FGFs (FGF2, FGF receptor 1), plus ING5, and WNT6. The microarray detection patterns suggest that hES/iPS cells exhibit suppressed circadian competence, underexpression of early differentiation markers, and more robust expression of generic pluripotency genes, in keeping with an artificial state of continual uncommitted cell division. In contrast, gene expression patterns of the 8C embryo suggest that

  13. The impact of commercialisation on public perceptions of stem cell research: exploring differences across the use of induced pluripotent cells, human and animal embryos.

    Science.gov (United States)

    Critchley, Christine R; Bruce, Gordana; Farrugia, Matthew

    2013-10-01

    The development of pluripotent cells that enable stem cell research (SCR) without destroying human embryos is now a leading priority for science. Public and political controversies associated with human embryonic SCR experienced in the recent past should be alleviated if scientists no longer need to harvest cells from human embryos. This research suggests however additional issues needing attention in order to gain the public's trust and support: the use of mouse embryos and the commercialisation of research. Using a representative sample of 2,800 Australians, and an experimental telephone survey design, this research compared levels and predictors of public support for stem cell research across three cell source conditions: human embryo (HE), mouse embryo (ME) and induced pluripotent cells (iPSCs). The results revealed that the public were significantly more likely to support research using iPSCs than HE and ME cells and public compared to private research (regardless of the cell source). There was no significant difference in support for HE compared to ME research, but the former was viewed as more likely to lead to accessible health care benefits and to be associated with more trustworthy scientists. The results of a multimediation structural equation model showed that the primary reason support for SCR significantly dropped in a private compared to public context (i.e., the commercialisation effect) was because public scientists were trusted more than private scientists. This effect was consistent across all three SCR materials, suggesting that the use of mouse embryos or even iPSCs will not reduce the publics' concern with commercialised science. The implications these results have for public acceptance of stem cell and animal research are discussed in relation to possible solutions such as increasing public awareness of the regulation of animal research and benefit sharing.

  14. Pluripotent stem cells from cloned human embryos: success at long last.

    Science.gov (United States)

    Trounson, Alan; DeWitt, Natalie D

    2013-06-06

    Recently in Cell, Mitalipov and colleagues report an advance that has eluded scientists for over a decade-the successful derivation of embryonic stem cell lines using somatic cell nuclear transfer, or SCNT (Tachibana et al., 2013).

  15. The First Human Cloned Embryo.

    Science.gov (United States)

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  16. A Euploid Line of Human Embryonic Stem Cells Derived from a 43,XX,dup(9q),+12,-14,-15,-18,-21 Embryo

    Science.gov (United States)

    Fonseca, Simone Aparecida Siqueira; Costas, Roberta Montero; Morato-Marques, Mariana; Costa, Silvia; Alegretti, Jose Roberto; Rosenberg, Carla; da Motta, Eduardo Leme Alves; Serafini, Paulo C.; Pereira, Lygia V.

    2015-01-01

    Aneuploid embryos diagnosed by FISH-based preimplantation genetic screening (PGS) have been shown to yield euploid lines of human embryonic stem cells (hESCs) with a relatively high frequency. Given that the diagnostic procedure is usually based on the analysis of 1–2 blastomeres of 5 to 10-cell cleavage-stage embryos, mosaicism has been a likely explanation for the phenomena. However, FISH-based PGS can have a significant rate of misdiagnosis, and therefore some of those lines may have been derived from euploid embryos misdiagnosed as aneuploid. More recently, coupling of trophectoderm (TE) biopsy at the blastocyst stage and array-CGH lead to a more informative form of PGS. Here we describe the establishment of a new line of hESCs from an embryo with a 43,XX,dup(9q),+12,-14,-15,-18,-21 chromosomal content based on array-CGH of TE biopsy. We show that, despite the complex chromosomal abnormality, the corresponding hESC line BR-6 is euploid (46,XX). Single nucleotide polymorphism analysis showed that the embryo´s missing chromosomes were not duplicated in BR-6, suggesting the existence of extensive mosaicism in the TE lineage. PMID:26540511

  17. Whole-blastocyst culture followed by laser drilling technology enhances the efficiency of inner cell mass isolation and embryonic stem cell derivation from good- and poor-quality mouse embryos: new insights for derivation of human embryonic stem cell lines.

    Science.gov (United States)

    Cortes, J L; Sánchez, L; Catalina, P; Cobo, F; Bueno, C; Martínez-Ramirez, A; Barroso, A; Cabrera, C; Ligero, G; Montes, R; Rubio, R; Nieto, A; Menendez, P

    2008-04-01

    The optimization of human embryonic stem (hES) cell line derivation methods is challenging because many worldwide laboratories have neither access to spare human embryos nor ethical approval for using supernumerary human embryos for hES cell derivation purposes. Additionally, studies performed directly on human embryos imply a waste of precious human biological material. In this study, we developed a new strategy based on the combination of whole-blastocyst culture followed by laser drilling destruction of the trophoectoderm for improving the efficiency of inner cell mass (ICM) isolation and ES cell derivation using murine embryos. Embryos were divided into good- and poor-quality embryos. We demonstrate that the efficiency of both ICM isolation and ES cell derivation using this strategy is significantly superior to whole-blastocyst culture or laser drilling technology itself. Regardless of the ICM isolation method, the ES cell establishment depends on a feeder cell growth surface. Importantly, this combined methodology can be successfully applied to poor-quality blastocysts that otherwise would not be suitable for laser drilling itself nor immunosurgery in an attempt to derive ES cell lines due to the inability to distinguish the ICM. The ES cell lines derived by this combined method were characterized and shown to maintain a typical morphology, undifferentiated phenotype, and in vitro and in vivo three germ layer differentiation potential. Finally, all ES cell lines established using either technology acquired an aneuploid karyotype after extended culture periods, suggesting that the method used for ES cell derivation does not seem to influence the karyotype of the ES cells after extended culture. This methodology may open up new avenues for further improvements for the derivation of hES cells, the majority of which are derived from frozen, poor-quality human embryos.

  18. Embryonic stem cells from blastomeres maintaining embryo viability.

    Science.gov (United States)

    Klimanskaya, Irina

    2013-01-01

    A wide variety of cell and tissue types that are sought in regenerative medicine can be generated from embryonic stem cells (ESCs), and currently two derivatives of human embryonic stem cells (hESCs) have entered human clinical trials. However, the ethical controversy surrounding this technology, which uses preimplantation human embryos to generate cell lines, is limiting research and the development of new therapies. Several new technologies such as induced pluripotent cells or parthenogenetically derived pluripotent cells hold great promise, but more research is needed before their derivatives can be proven to be safe and functional for use in human patients. The blastomere biopsy-based technique allows the derivation of human ESClines without sacrificing a human embryo and was shown to be robust and produce safe and functional derivatives of therapeutic value.

  19. Identification and isolation of embryonic stem cells in reproductive endocrinology: theoretical protocols for conservation of human embryos derived from in vitro fertilization

    Directory of Open Access Journals (Sweden)

    Neri Queenie V

    2005-07-01

    Full Text Available Abstract Background Embryonic stem cells (ESC are pluripotent cells obtained from the inner cell mass (ICM of blastocysts derived from in vitro culture associated with reproductive endocrinology therapy. Human ESCs are regarded as highly significant since they retain the capacity to differentiate into any of approximately 200 unique cell types. Human ESC research is controversial because to acquire such cells, the ICM of human blastocysts must be manipulated in a way that renders embryos nonviable and unsuitable for transfer in utero. Techniques to yield competent ESCs with conservation of source blastocysts would satisfy many objections against ESC research, but at present such approaches remain largely untested. Results and discussion We contrast experimental culture of single blastomeres obtained by 1 non-destructive biopsy of embryos destined for transfer, and 2 isolation of karyotypically normal blastomeres from disaggregated ("dead" embryos considered unsuitable for transfer, and evaluate these approaches with regard to production of ESCs. Pluripotency was confirmed by morphological criteria and by quantification of divergent homeodomain proteins specific to undifferentiated cell development. Following ESC isolation and identification, assessment was conducted according to a novel ESC grading system, also proposed here. Conclusion The role of reproductive endocrinology in ESC research remains paramount. In this report, we hypothesize new and expand on existing strategies having the potential to enhance human ESC isolation, identification and in vitro maintenance.

  20. Embryos, Clones, and Stem Cells: A Scientific Primer

    Directory of Open Access Journals (Sweden)

    Kenyon S. Tweedell

    2004-01-01

    Full Text Available This article is intended to give the nonspecialist an insight into the nuances of “clones”, cloning, and stem cells. It distinguishes embryonic and adult stem cells, their normal function in the organism, their origin, and how they are recovered to produce stem cell lines in culture. As background, the fundamental processes of embryo development are reviewed and defined, since the manipulation of stem cell lines into desired specialized cells employs many of the same events. Stem cells are defined and characterized and shown how they function in the intact organism during early development and later during cell regeneration in the adult. The complexity of stem cell recovery and their manipulation into specific cells and tissue is illustrated by reviewing current experimentation on both embryonic and adult stem cells in animals and limited research on human stem cell lines. The current and projected use of stem cells for human diseases and repair, along with the expanding methodology for the recovery of human embryonic stem cells, is described. An assessment on the use of human embryonic stem cells is considered from ethical, legal, religious, and political viewpoints.

  1. Stem cell research on other worlds, or why embryos do not have a right to life.

    Science.gov (United States)

    Blackford, R

    2006-03-01

    Anxieties about the creation and destruction of human embryos for the purpose of scientific research on embryonic stem cells have given a new urgency to the question of whether embryos have moral rights. This article uses a thought experiment involving two possible worlds, somewhat removed from our own in the space of possibilities, to shed light on whether early embryos have such rights as a right not to be destroyed or discarded (a "right to life"). It is argued that early embryos do not have meaningful interests or any moral rights. Accordingly, claims about the moral rights of embryos do not justify restrictions on stem cell research.

  2. Stem cells from residual IVF-embryos - Continuation of life justifies isolation.

    Science.gov (United States)

    Bongaerts, Ger P A; Severijnen, René S V M

    2007-01-01

    Embryonic stem cells are undifferentiated pluripotent cells that can indefinitely grow in vitro. They are derived from the inner mass of early embryos. Because of their ability to differentiate into all three embryonic germ layers, and finally into specialized somatic cell types, human embryonic stem cells represent important material for studying developmental biology and cell replacement therapy. They are usually isolated from excess human IVF-embryos. Since many people regard isolation of human stem cells as intentional killing of the embryo, it is a very difficult ethical problem. Similar feelings concern medical or scientific use of these stem cells. Is this feeling correct, or does it arise from a sentimental view? The problem encloses two aspects: (i) use of stem cells for medical therapy and scientific research and (ii) isolation of stem cells from human IVF-embryos. Worldwide human tissues are cultured, transplanted and used for medical and scientific research. Therefore, it may be concluded that factual use of human embryonic stem cells cannot be a real ethical problem. The main key of the problem seems to be hidden in the exact definition of 'death'; in other words: is there nothing between 'death' and 'life'? Bacterial spores, lyophilised bacteria and other micro-organisms, micro-organisms stored in glycerol mixtures at -80 degrees C and tissue cultures and sperm cells stored in liquid nitrogen, they are all neither dead nor alive, but still viable. From this point it is clear that there is more than the antithesis 'dead' versus 'alive'. In addition, we think that there is still another alternative: partial death. The present view concerning isolation of stem cells implies that residual embryos and thus new human lives are killed, and that therefore these embryos must be (passively) destroyed. However, it is especially the very well planned IVF-procedure that makes that passive destruction of not-implanted embryos means intentional killing. By isolation

  3. Human embryo cloning prohibited in Hong Kong.

    Science.gov (United States)

    Liu, Athena

    2005-12-01

    Since the birth of Dolly (the cloned sheep) in 1997, debates have arisen on the ethical and legal questions of cloning-for-biomedical-research (more commonly termed "therapeutic cloning") and of reproductive cloning using human gametes. Hong Kong enacted the Human Reproductive Technology Ordinance (Cap 561) in 2000. Section 15(1)(e) of this Ordinance prohibits the "replacing of the nucleus of a cell of an embryo with a nucleus taken from any other cell," i.e., nucleus substitution. Section 15(1)(f) prohibits the cloning of any embryo. The scope of the latter, therefore, is arguably the widest, prohibiting all cloning techniques such as cell nucleus replacement, embryo splitting, parthenogenesis, and cloning using stem cell lines. Although the Human Reproductive Technology Ordinance is not yet fully operative, this article examines how these prohibitions may adversely impact on basic research and the vision of the Hong Kong scientific community. It concludes that in light of recent scientific developments, it is time to review if the law offers a coherent set of policies in this area.

  4. New mechanism for neural stem cell maintenance in early embryos

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Teamning up with co-workers from Japan, UK and US,CAS biochemists have revealed a novel mechanism for maintaining neural stem cells in early embryos. Their work was published on the 6 August issue of Cell Development.

  5. Development of hematopoietic stem cell activity in the mouse embryo.

    NARCIS (Netherlands)

    A.M. Müller (Albrecht); A. Medvinsky; J. Strouboulis (John); F.G. Grosveld (Frank); E.A. Dzierzak (Elaine)

    1994-01-01

    textabstractThe precise time of appearance of the first hematopoietic stem cell activity in the developing mouse embryo is unknown. Recently the aorta-gonad-mesonephros region of the developing mouse embryo has been shown to possess hematopoietic colony-forming activity (CFU-S) in irradiated recipie

  6. Attitudes of patients, healthcare professionals and ethicists towards embryonic stem cell research and donation of gametes and embryos in Germany.

    Science.gov (United States)

    Krones, T; Neuwohner, E; Bock, K; Manolopoulos, K; Tinneberg, H R; Richter, G

    2006-11-01

    Due to the Embryo Protection Act, creation of supernumerary embryos, as well as egg and embryo donation, is prohibited in Germany. Human stem cell research is regulated through the Act on stem cells that came into force in 2002. A cross-sectional survey of 101 IVF couples (n=202) in two fertility centres, and representative samples of healthcare professionals and ethicists (n=879), was carried out, and their attitudes towards embryonic stem cell research and donation of gametes and embryos compared. A clear majority of IVF couples favoured legalization of egg and embryo donation and embryonic stem cell research for various purposes. The willingness of couples to donate was related to purpose and to other independent influences. The majority of physicians voted for legalization of embryonic stem cell production from surplus embryos. Most human geneticists and obstetricians approved egg, but not embryo, donation to other couples. Ethicists and midwives were opposed to every kind of donation and research on surplus embryos. The IVF couples surveyed have positive attitudes towards donation and research using surplus embryos, whereas the healthcare professionals and ethicists are predominantly sceptical about most research activities destroying human embryos. This difference should be considered carefully in legal and ethical discussions on reprogenetics.

  7. Microfluidics for gametes, embryos, and embryonic stem cells.

    Science.gov (United States)

    Smith, G D; Swain, J E; Bormann, C L

    2011-01-01

    Microfluidics is a young but established field that holds significant potential for scientific discovery. The utility of microfluidics can improve our knowledge of basic biology as well as expand our understanding in specialized areas such as assisted reproduction and stem cell developmental biology. This review describes the technology of microfluidics and discusses applications within assisted reproduction technology and embryonic stem cell growth and directed differentiation. Development of an integrated microfluidic platform for assisted reproduction, which can manipulate gametes, embryos, embryonic stem cells, their culture environment, and incorporate biomarker analysis, could have a dramatic impact on the basic understanding of embryo/embryonic stem cell development, as well as provide significant improvements in current technologies used to treat infertility, preserve fertility, and derive therapeutic cells from stem cells.

  8. Addressing the ethical issues raised by synthetic human entities with embryo-like features

    NARCIS (Netherlands)

    Aach, John; Lunshof, Jeantine; Iyer, Eswar; Church, George M.

    2017-01-01

    The "14-day rule" for embryo research stipulates that experiments with intact human embryos must not allow them to develop beyond 14 days or the appearance of the primitive streak. However, recent experiments showing that suitably cultured human pluripotent stem cells can self organize and recapitul

  9. Stem cells from residual IVF-embryos - Continuation of life justifies isolation.

    NARCIS (Netherlands)

    Bongaerts, G.P.A.; Severijnen, R.S.V.M.

    2007-01-01

    Embryonic stem cells are undifferentiated pluripotent cells that can indefinitely grow in vitro. They are derived from the inner mass of early embryos. Because of their ability to differentiate into all three embryonic germ layers, and finally into specialized somatic cell types, human embryonic ste

  10. Stem cells from residual IVF-embryos - Continuation of life justifies isolation.

    NARCIS (Netherlands)

    Bongaerts, G.P.A.; Severijnen, R.S.V.M.

    2007-01-01

    Embryonic stem cells are undifferentiated pluripotent cells that can indefinitely grow in vitro. They are derived from the inner mass of early embryos. Because of their ability to differentiate into all three embryonic germ layers, and finally into specialized somatic cell types, human embryonic

  11. Transcriptome analysis of mouse stem cells and early embryos.

    Directory of Open Access Journals (Sweden)

    Alexei A Sharov

    2003-12-01

    Full Text Available Understanding and harnessing cellular potency are fundamental in biology and are also critical to the future therapeutic use of stem cells. Transcriptome analysis of these pluripotent cells is a first step towards such goals. Starting with sources that include oocytes, blastocysts, and embryonic and adult stem cells, we obtained 249,200 high-quality EST sequences and clustered them with public sequences to produce an index of approximately 30,000 total mouse genes that includes 977 previously unidentified genes. Analysis of gene expression levels by EST frequency identifies genes that characterize preimplantation embryos, embryonic stem cells, and adult stem cells, thus providing potential markers as well as clues to the functional features of these cells. Principal component analysis identified a set of 88 genes whose average expression levels decrease from oocytes to blastocysts, stem cells, postimplantation embryos, and finally to newborn tissues. This can be a first step towards a possible definition of a molecular scale of cellular potency. The sequences and cDNA clones recovered in this work provide a comprehensive resource for genes functioning in early mouse embryos and stem cells. The nonrestricted community access to the resource can accelerate a wide range of research, particularly in reproductive and regenerative medicine.

  12. Transcriptome Analysis of Mouse Stem Cells and Early Embryos

    Science.gov (United States)

    Sharov, Alexei A; Piao, Yulan; Matoba, Ryo; Dudekula, Dawood B; Qian, Yong; VanBuren, Vincent; Falco, Geppino; Martin, Patrick R; Stagg, Carole A; Bassey, Uwem C; Wang, Yuxia; Carter, Mark G; Hamatani, Toshio; Aiba, Kazuhiro; Akutsu, Hidenori; Sharova, Lioudmila; Tanaka, Tetsuya S; Kimber, Wendy L; Yoshikawa, Toshiyuki; Jaradat, Saied A; Pantano, Serafino; Nagaraja, Ramaiah; Boheler, Kenneth R; Taub, Dennis; Hodes, Richard J; Longo, Dan L; Schlessinger, David; Keller, Jonathan; Klotz, Emily; Kelsoe, Garnett; Umezawa, Akihiro; Vescovi, Angelo L; Rossant, Janet; Kunath, Tilo; Hogan, Brigid L. M; Curci, Anna; D'Urso, Michele; Kelso, Janet; Hide, Winston

    2003-01-01

    Understanding and harnessing cellular potency are fundamental in biology and are also critical to the future therapeutic use of stem cells. Transcriptome analysis of these pluripotent cells is a first step towards such goals. Starting with sources that include oocytes, blastocysts, and embryonic and adult stem cells, we obtained 249,200 high-quality EST sequences and clustered them with public sequences to produce an index of approximately 30,000 total mouse genes that includes 977 previously unidentified genes. Analysis of gene expression levels by EST frequency identifies genes that characterize preimplantation embryos, embryonic stem cells, and adult stem cells, thus providing potential markers as well as clues to the functional features of these cells. Principal component analysis identified a set of 88 genes whose average expression levels decrease from oocytes to blastocysts, stem cells, postimplantation embryos, and finally to newborn tissues. This can be a first step towards a possible definition of a molecular scale of cellular potency. The sequences and cDNA clones recovered in this work provide a comprehensive resource for genes functioning in early mouse embryos and stem cells. The nonrestricted community access to the resource can accelerate a wide range of research, particularly in reproductive and regenerative medicine. PMID:14691545

  13. Derivation of HVR1, HVR2 and HVR3 human embryonic stem cell lines from IVF embryos after preimplantation genetic diagnosis (PGD for monogenic disorder

    Directory of Open Access Journals (Sweden)

    Abdelkrim Hmadcha

    2016-05-01

    Full Text Available From 106 human blastocyts donate for research after in vitro fertilization (IVF and preimplantation genetic diagnosis (PGD for monogenetic disorder, 3 human embryonic stem cells (hESCs HVR1, HVR2 and HVR3 were successfully derived. HVR1 was assumed to be genetically normal, HVR2 carrying Becker muscular dystrophy and HVR3 Hemophilia B. Despite the translocation t(9;15(q34.3;q14 detected in HVR2, all the 3 cell lines were characterised in vitro and in vivo as normal hESCs lines and were registered in the Spanish Stem Cell Bank.

  14. The ethics of cloning and human embryo research.

    Science.gov (United States)

    Saran, Madeleine

    2002-01-01

    The successful cloning experiments that led to Dolly in 1997 have raised many ethical and policy questions. This paper will focus on cloning research in human embryonic cells. The possible gains of the research will be judged against the moral issues of doing research on a person. This paper concludes that while the embryo has some moral status, its moral status is outweighed by the multitude of benefits that embryonic stem cell research will bring to humanity. Policy suggestions are given for dealing with this new and developing field of stem cell research.

  15. Genomic imprinting in primate embryos and embryonic stem cells.

    Science.gov (United States)

    Mitalipov, Shoukhrat M

    2006-01-01

    Embryonic stem (ES) cells hold promise for cell and tissue replacement approaches to treating human diseases. However, long-term in vitro culture and manipulations of ES cells may adversely affect their epigenetic integrity including imprinting. Disruption or inappropriate expression of imprinted genes is associated with several clinically significant syndromes and tumorigenesis in humans. We demonstrated aberrant biallelic expression of IGF2 and H19 in several rhesus monkey ES cell lines while SNRPN and NDN were normally imprinted and expressed from the paternal allele. In contrast, expanded blastocyst-stage embryos, from which these ES cells were derived, exhibited normal paternal expression of IGF2 and maternal expression of H19. To test the possibility that aberrant methylation at an imprinting centre (IC) upstream of H19 accounts for the relaxed imprinting of IGF2 and H19, we performed comprehensive methylation analysis by investigating methylation profiles of CpG sites within the IGF2/H19 IC. Our results demonstrate abnormal hypermethylation within the IGF2/H19 IC in all analysed ES cell lines consistent with biallelic expression of these genes. Cellular overproliferation and tumour formation resulting from tissue or cell transplantation are potential problems that must be addressed before clinical trials of ES cell-based therapy are initiated.

  16. Human embryos in the original position?

    Science.gov (United States)

    DiSilvestro, Russell

    2005-06-01

    Two different discussions in John Rawls' A Theory of Justice lead naturally to a rather conservative position on the moral status of the human embryo. When discussing paternalism, he claims that the parties in the original position would seek to protect themselves in case they end up as incapacitated or undeveloped human beings when the veil of ignorance is lifted. Since human embryos are examples of such beings, the parties in the original position would seek to protect themselves from their embryonic stages onward. When discussing the basis of equality, Rawls claims that the parties in the original position would guarantee basic rights for all those with the capacity to take part in this original position. To guarantee the basic rights of infants and young children, he goes on to interpret this capacity as a "potentiality that is ordinarily realized in due course." Since human embryos have this potentiality, they too should have basic rights.

  17. Production of Buffalo Embryonic Stem Cell from HMC Embryos

    Directory of Open Access Journals (Sweden)

    M. Zandi

    2016-06-01

    Full Text Available Embryonic stem cells (ESCs are derived from the inner cell mass (ICM of blastocyst and differentiate into all three embryonic germ layers: ectoderm, endoderm, and mesoderm. In this study, ESCs are derived from Hand Made Cloning (HMG blastocysts and their efficiencies compared to ESCs derived from In Vitro Fertilization (IVF embryos. Feeder layer was used for ESCs culture, and culture medium consisting of Knockout- Dulbecco’s Modified Eagle’s Medium (Ko-DMEM supplemented with Knockout Serum Replacement (KSR, Leukemia Inhibitory Factor (LIF, Basic Fibroblast Growth Factor-2 (FGF-2, L-glutamine, nonessential amino acids and gentamicin. The cell surface antigens used for characterization were the SSEA-1, SSEA-4, TRA-1-60 and TRA-1-81 and the pluripotency markers were NANOG, OCT3/4 and SOX2. Results showed that, the growth rate of ESCs colonies in ESCs from IVF embryos was significantly higher than ESCs from HMG embryos (120% compared with 65%, respectively. Not only real-time PCR results revealed the same expression level of SOX2, OCT3/4 and cMYC between them, but also ESCs from HMG embryos resulted to higher expression of NANOG. Both of ESCs groups maintain in pluripotency state for more than two years and differentiated to the different types of cells like neuron, epithelial, lipid and muscle cells.

  18. The establishment of human embryonic stem cell lines from embryos of women with polycystic ovary syndrome%多囊卵巢综合征源性人胚胎干细胞系的建立

    Institute of Scientific and Technical Information of China (English)

    李朋粉; 孙莹璞; 王芳; 孔慧娟; 白爱红; 赵芳

    2011-01-01

    目的:利用多囊卵巢综合征(PCOS)患者体外受精周期中废弃胚胎建立人胚胎干细胞(hESCs)系.方法:收集PCOS患者体外受精-胚胎移植周期中废弃的新鲜或冷冻胚胎,序贯培养至囊胚,机械分离内细胞团,接种于混合饲养层(小鼠胚胎成纤维细胞:人包皮成纤维细胞为1:1),传代培养.对稳定传代的hESCs进行形态学观察、碱性磷酸酶染色、阶段特异性胚胎抗原-4、转录因子OCT-4的表达、核型分析、体内、外分化潜能鉴定.结果:①收集到59枚新鲜废胚,培养后获得14枚囊胚,分离11个内细胞团,贴壁、传代后建立5株hESCs系,均具备hESC特性.②收集到解冻胚胎19枚,培养后获得6枚囊胚,分离5个内细胞团,形成5个原代克隆,目前传至3~4代.结论:建立了PCOS源性hESCs系,为研究PCOS发病机理、筛选候选基因、基因定位及基因治疗等提供良好的生物学模型;废弃的新鲜及冷冻胚胎均可作为hESC建系的材料来源.%Objective: To establish human embryonic stem cells (hESCs) lines derived from discarded embryos of women with polycystic ovary syndrome (PCOS) in vitro fertilization and embryo transfer (IVF-ET). Methods: The discarded fresh and frozen embryos were recruited from the women with PCOS undergoing IVF-ET program. The embryos were cultured into blastula by the sequential culture. After isolation by mechanical method, the inner cell mass (ICM) was implanted on the mixed feeder layer (the ratio of mouse embryonic fibroblast and human foreskin fibroblast was 11)and subcultured. Finally, the cells were authenticated as hESCs by various methods, which included morphological observation, test for experssion of alkaline phosphates (AKP), stage-specific embryonic antigen-4 (SSEA-4)and OCT- 4, karyotype analysis, differentiation potentials in vivo and in vitro. Results: A total of 14 blastulae were obtained from 59 low quality fresh embryos, which resulted in the formation of 11 ICM and 5

  19. The moral status of the embryo: the human embryo in the UK Human Fertilisation and Embryology (Research Purposes) Regulation 2001 debate.

    Science.gov (United States)

    Bahadur, G

    2003-01-01

    The use of the embryo in research into birth defects, infertility and the possible therapeutic value of embryonic stem cells, has given rise to vigorous discussion of the ethical, moral and legal status of the embryo. This paper considers the parliamentary debate that surrounded the passing of legislation in the UK in 2000 governing the use of the embryo in research. Underlying disagreement by members of Parliament as to whether embryo research was permissible, were considerable differences regarding when life was thought to begin--whether at the moment of fertilization of the egg, or whether after 14 days, at the time of the beginnings of cell differentiation, and the point after which the embryo can no longer split to form twins. Those who favoured the latter view argued that, while the conceptus might possess a unique genetic formula, it had only the potential for life before 14 days, the development of human life being a gradual and continuous process. They considered it mistaken to accord the embryo full human rights. Those who adopted an opposed standpoint insisted that life was present and actual from the moment of conception and therefore sacrosanct and inviolable. The notion of the pre-embryo, they maintained, merely serves to disguise the embryo's humanity.

  20. Embryo as epiphenomenon: some cultural, social and economic forces driving the stem cell debate.

    Science.gov (United States)

    Green, R M

    2008-12-01

    Our human embryonic stem cell debates are not simply about good or bad ethical arguments. The fetus and the embryo have instead become symbols for a larger set of value conflicts occasioned by social and cultural changes. Beneath our stem cell debates lie conflicts between those who would privilege scientific progress and individual choice and others who favour the sanctity of family life and traditional family roles. Also at work, on both the national and international levels, is the use of the embryo by newly emergent social groups to express resentment against cultural elites. The organisational needs of religious groups have also played a role, with the issue of protection of the embryo and fetus serving as a useful means of rallying organisational allegiance in the Roman Catholic and evangelical communities. Because the epiphenomenal moral positions on the status and use of the embryo are driven by the powerful social, cultural or economic forces beneath them, they will most likely change only with shifts in the underlying forces that sustain them.

  1. Human embryo twinning with applications in reproductive medicine.

    Science.gov (United States)

    Illmensee, Karl; Levanduski, Mike; Vidali, Andrea; Husami, Nabil; Goudas, Vasilios T

    2010-02-01

    To assess the efficacy of human embryo twinning by blastomere biopsy at different early embryonic stages (splitting efficiency) and to determine the in vitro developmental capacity of twinned human embryos (developmental efficiency). Randomized comparative study. Private IVF centers. Couples undergoing IVF donating triploid embryos. Embryos at the 2- to 5- and 6- to 8-cell stage were split into twin embryos. Half the number of blastomeres from donor embryos were removed and inserted into recipient empty zonae pellucidae. After embryo splitting, donor and recipient embryos were cultured in vitro. Development of twinned embryos to the blastocyst stage. The number of developing embryos obtained after splitting could be increased in comparison with the number of embryos available before splitting at the 6- to 8-cell stage but not at the 2- to 5-cell stage (splitting efficiency). Splitting of 6- to 8-cell embryos yielded superior rates of twin embryos developing to blastocysts (developmental efficiency). Twinning success was related to the superior morphological quality of embryos used for splitting. This is the first report on twinned human embryos developing to blastocysts. This study exhibits the potential for novel applications in human assisted reproduction. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Transplantation of mammalian embryonic stem cells and their derivatives to avian embryos.

    Science.gov (United States)

    Goldstein, Ronald S

    2010-09-01

    Xenografting of normal and transformed mammalian tissues and cells to chick embryos has been performed for almost 100 years. Embryonic stem cells, derived more than 25 years ago from murine, and more than 10 years ago from human blastocysts, have transformed many fields of biological research. There is a growing body of studies combining these two widely-used experimental systems. This review surveys those reports in which murine or human embryonic stem cells, or differentiated derivatives of these pluripotent stem cells, were transplanted to embryonated chick eggs. Many of these studies have utilized the unique characteristics of both experimental models to obtain answers to developmental questions that are difficult or impossible to approach with xenografting to adult rodents or tissue culture-only techniques.

  3. Potential of human twin embryos generated by embryo splitting in assisted reproduction and research.

    Science.gov (United States)

    Noli, Laila; Ogilvie, Caroline; Khalaf, Yacoub; Ilic, Dusko

    2017-03-01

    Embryo splitting or twinning has been widely used in veterinary medicine over 20 years to generate monozygotic twins with desirable genetic characteristics. The first human embryo splitting, reported in 1993, triggered fierce ethical debate on human embryo cloning. Since Dolly the sheep was born in 1997, the international community has acknowledged the complexity of the moral arguments related to this research and has expressed concerns about the potential for reproductive cloning in humans. A number of countries have formulated bans either through laws, decrees or official statements. However, in general, these laws specifically define cloning as an embryo that is generated via nuclear transfer (NT) and do not mention embryo splitting. Only the UK includes under cloning both embryo splitting and NT in the same legislation. On the contrary, the Ethics Committee of the American Society for Reproductive Medicine does not have a major ethical objection to transferring two or more artificially created embryos with the same genome with the aim of producing a single pregnancy, stating that 'since embryo splitting has the potential to improve the efficacy of IVF treatments for infertility, research to investigate the technique is ethically acceptable'. Embryo splitting has been introduced successfully to the veterinary medicine several decades ago and today is a part of standard practice. We present here an overview of embryo splitting experiments in humans and non-human primates and discuss the potential of this technology in assisted reproduction and research. A comprehensive literature search was carried out using PUBMED and Google Scholar databases to identify studies on embryo splitting in humans and non-human primates. 'Embryo splitting' and 'embryo twinning' were used as the keywords, alone or in combination with other search phrases relevant to the topics of biology of preimplantation embryos. A very limited number of studies have been conducted in humans and non-human

  4. Embryonic death and the creation of human embryonic stem cells

    OpenAIRE

    Landry, Donald W.; Zucker, Howard A.

    2004-01-01

    The creation of human embryonic stem cells through the destruction of a human embryo pits the value of a potential therapeutic tool against that of an early human life. This contest of values has resulted in a polarized debate that neglects areas of common interest and perspective. We suggest that a common ground for pursuing research on human embryonic stem cells can be found by reconsidering the death of the human embryo and by applying to this research the ethical norms of essential organ ...

  5. Embryonic death and the creation of human embryonic stem cells.

    Science.gov (United States)

    Landry, Donald W; Zucker, Howard A

    2004-11-01

    The creation of human embryonic stem cells through the destruction of a human embryo pits the value of a potential therapeutic tool against that of an early human life. This contest of values has resulted in a polarized debate that neglects areas of common interest and perspective. We suggest that a common ground for pursuing research on human embryonic stem cells can be found by reconsidering the death of the human embryo and by applying to this research the ethical norms of essential organ donation.

  6. Origin of the hematopoietic system in the human embryo.

    Science.gov (United States)

    Julien, Emmanuelle; El Omar, Reine; Tavian, Manuela

    2016-11-01

    The continuous generation of blood cells throughout life relies on the existence of hematopoietic stem cells (HSC) generated during embryogenesis. Given the importance of HSC transplantation in cell-based therapeutic approaches, considerable efforts have been made toward understanding the developmental origins of embryonic HSC. Adult-type HSC are first generated in the aorta-gonad-mesonephros (AGM) region between days 27 and 40 of human embryonic development, but an elusive blood-forming potential is present earlier in the underlying splanchnopleura. It is relatively well accepted that the HSC emerge in the AGM through a hemogenic endothelium, but the direct precursor of this cell type remains to be clearly identified. This review is intended to summarize the recent advances made to understand the origins of hematopoietic stem cells in the early human embryo. In addition, we discuss in detail the discovery of the angiotensin-converting enzyme (ACE) as a novel marker of human HSC and of prehematopoietic precursors inside the embryo. © 2016 Federation of European Biochemical Societies.

  7. Human fetal mesenchymal stem cells.

    Science.gov (United States)

    O'Donoghue, Keelin; Chan, Jerry

    2006-09-01

    Stem cells have been isolated at all stages of development from the early developing embryo to the post-reproductive adult organism. However, the fetal environment is unique as it is the only time in ontogeny that there is migration of stem cells in large numbers into different organ compartments. While fetal neural and haemopoietic stem cells (HSC) have been well characterised, only recently have mesenchymal stem cells from the human fetus been isolated and evaluated. Our group have characterised in human fetal blood, liver and bone marrow a population of non-haemopoietic, non-endothelial cells with an immunophenotype similar to adult bone marrow-derived mesenchymal stem cells (MSC). These cells, human fetal mesenchymal stem cells (hfMSC), are true multipotent stem cells with greater self-renewal and differentiation capacity than their adult counterparts. They circulate in first trimester fetal blood and have been found to traffic into the maternal circulation, engrafting in bone marrow, where they remain microchimeric for decades after pregnancy. Though fetal microchimerism has been implicated in the pathogenesis of autoimmune disease, the biological role of hfMSC microchimerism is unknown. Potential downstream applications of hfMSC include their use as a target cell for non-invasive pre-natal diagnosis from maternal blood, and for fetal cellular and gene therapy. Using hfMSC in fetal therapy offers the theoretical advantages of avoidance of immune rejection, increased engraftment, and treatment before disease pathology sets in. Aside from allogeneic hfMSC in utero transplantation, the use of autologous hfMSC has been brought a step forward with the development of early blood sampling techniques, efficient viral transduction and clonal expansion. Work is ongoing to determine hfMSC fate post-transplantation in murine models of genetic disease. In this review we will examine what is known about hfMSC biology, as well as discussing areas for future research. The

  8. Human embryonic stem cell research debates: a confucian argument.

    Science.gov (United States)

    Tsai, D F-C

    2005-11-01

    Human embryonic stem cell research can bring about major biomedical breakthroughs and thus contribute enormously to human welfare, yet it raises serious moral problems because it involves using human embryos for experiment. The "moral status of the human embryo" remains the core of such debates. Three different positions regarding the moral status of the human embryo can be categorised: the "all" position, the "none" position, and the "gradualist" position. The author proposes that the "gradualist" position is more plausible than the other two positions. Confucius's moral principle of jen, which proposes a unique theory of "love of gradation", and the principle of yi, which advocates "due treatment for persons", are then explored. The author then argues that our moral obligations to do good to other living organisms, persons, and our families are different. Putting together the "gradualist" position on the human embryo, and Confucius's theories of "love of gradation" and "due treatment for persons", the author concludes that the early embryo has less ethical significance than the later fetus and adult human. The moral obligation we have toward persons is clearer and stronger than that which we have toward human embryos. Embryo research is justifiable if it brings enormous welfare to human persons that cannot be otherwise achieved. The "love of gradation" requires us, however, to extend love and respect towards other entities according to their different status. We should therefore be very cautious in using human embryos for research, acknowledging the gradualist nature of their moral status.

  9. Ethical issues of the research on human embryonic stem cells.

    Science.gov (United States)

    Hotta, Yoshitaro

    2008-09-01

    This paper examines the debate on human embryonic stem cell (hES) research. In Japan, as in many Western countries, the moral status of the human embryo has been the main focus. There is a dichotomy between the advocates of research on hES cells and the advocates of the dignity of the embryos. Advocates of research on hES cells claim that the act of abandoning the embryo and the act of using it for research have the same moral status. Critics of research using embryos reject this position, claiming that the embryo has a status incommensurable with other values. This paper points out that the standpoint of the woman providing the embryos has been overlooked in this discussion.

  10. Researchers and firing squads: questions concerning the use of frozen human embryos.

    Science.gov (United States)

    Tully, Patrick

    2011-10-01

    Is it morally acceptable to use human embryos left over from fertility treatments in research that would harm or destroy them? Many answer "no" to this question on the grounds that all human beings, including human embryos, have a basic moral status that forbids such use. There are some, though, who accept this claim about the basic moral status of human embryos but who believe nevertheless that frozen human embryos which were generated for fertility treatments but which are no longer wanted for that project are a morally acceptable source of human embryonic stem cells and are acceptable subjects of other forms of research that would destroy them in course. The reasoning offered in defense of this position typically employs the claim that since these embryos are going to be discarded anyway, their possibly fruitful use by researchers is a preferable alternative and one that is not inconsistent with their basic moral status. Howard Curzer has offered a well-developed argument of this sort, defending the use of these embryos in the ways mentioned while at the same time allowing for their equal basic moral status. This article challenges Curzer's case and offers reasons to reject the moral acceptability of using even these to-be-discarded embryos as research material.

  11. Cryopreservation of embryos and oocytes in human assisted reproduction.

    Science.gov (United States)

    Konc, János; Kanyó, Katalin; Kriston, Rita; Somoskői, Bence; Cseh, Sándor

    2014-01-01

    Both sperm and embryo cryopreservation have become routine procedures in human assisted reproduction and oocyte cryopreservation is being introduced into clinical practice and is getting more and more widely used. Embryo cryopreservation has decreased the number of fresh embryo transfers and maximized the effectiveness of the IVF cycle. The data shows that women who had transfers of fresh and frozen embryos obtained 8% additional births by using their cryopreserved embryos. Oocyte cryopreservation offers more advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation, and postponing childbirth, and eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In this review, the basic principles, methodology, and practical experiences as well as safety and other aspects concerning slow cooling and ultrarapid cooling (vitrification) of human embryos and oocytes are summarized.

  12. Cryopreservation of Embryos and Oocytes in Human Assisted Reproduction

    Directory of Open Access Journals (Sweden)

    János Konc

    2014-01-01

    Full Text Available Both sperm and embryo cryopreservation have become routine procedures in human assisted reproduction and oocyte cryopreservation is being introduced into clinical practice and is getting more and more widely used. Embryo cryopreservation has decreased the number of fresh embryo transfers and maximized the effectiveness of the IVF cycle. The data shows that women who had transfers of fresh and frozen embryos obtained 8% additional births by using their cryopreserved embryos. Oocyte cryopreservation offers more advantages compared to embryo freezing, such as fertility preservation in women at risk of losing fertility due to oncological treatment or chronic disease, egg donation, and postponing childbirth, and eliminates religious and/or other ethical, legal, and moral concerns of embryo freezing. In this review, the basic principles, methodology, and practical experiences as well as safety and other aspects concerning slow cooling and ultrarapid cooling (vitrification of human embryos and oocytes are summarized.

  13. Response to: Dittrich et al.: Non-Embryo-Destructive Extraction of Pluripotent Embryonic Stem Cells - Overlooked Legal Prohibitions, Professional Legal Consequences and Inconsistencies in Patent Law.

    Science.gov (United States)

    Faltus, T; Storz, U

    2016-12-01

    The publication of "Non-embryo-destructive Extraction of Pluripotent Embryonic Stem Cells: Implications for Regenerative Medicine and Reproductive Medicine" by Dittrich et al. in Geburtshilfe und Frauenheilkunde 2015; 75: 1239-1242 1 describes various possibilities which could result from the non-embryo-destructive extraction of embryonic stem cells from human blastocysts. But implementing this method is more problematic, both legally and ethically, than the authors have represented it to be and is illegal in Germany. German patent DE 10 2004 062 184 on the non-embryo-destructive extraction of embryonic stem cells referred to by Dittrich et al. contravenes the higher-ranking case-law of the European Court of Justice. Ultimately, the non-embryo-destructive harvesting of embryonic stem cells with the aim of storing these cells for use in potential therapies as proposed by Dittrich et al. is prohibited in Germany and could lead to criminal prosecution.

  14. Diploid, but not haploid, human embryonic stem cells can be derived from microsurgically repaired tripronuclear human zygotes.

    Science.gov (United States)

    Fan, Yong; Li, Rong; Huang, Jin; Yu, Yang; Qiao, Jie

    2013-01-15

    Human embryonic stem cells have shown tremendous potential in regenerative medicine, and the recent progress in haploid embryonic stem cells provides new insights for future applications of embryonic stem cells. Disruption of normal fertilized embryos remains controversial; thus, the development of a new source for human embryonic stem cells is important for their usefulness. Here, we investigated the feasibility of haploid and diploid embryo reconstruction and embryonic stem cell derivation using microsurgically repaired tripronuclear human zygotes. Diploid and haploid zygotes were successfully reconstructed, but a large proportion of them still had a tripolar spindle assembly. The reconstructed embryos developed to the blastocyst stage, although the loss of chromosomes was observed in these zygotes. Finally, triploid and diploid human embryonic stem cells were derived from tripronuclear and reconstructed zygotes (from which only one pronucleus was removed), but haploid human embryonic stem cells were not successfully derived from the reconstructed zygotes when two pronuclei were removed. Both triploid and diploid human embryonic stem cells showed the general characteristics of human embryonic stem cells. These results indicate that the lower embryo quality resulting from abnormal spindle assembly contributed to the failure of the haploid embryonic stem cell derivation. However, the successful derivation of diploid embryonic stem cells demonstrated that microsurgical tripronuclear zygotes are an alternative source of human embryonic stem cells. In the future, improving spindle assembly will facilitate the application of triploid zygotes to the field of haploid embryonic stem cells.

  15. Search for naive human pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Simone Aparecida Siqueira Fonseca; Roberta Montero Costas; Lygia Veiga Pereira

    2015-01-01

    Normal mouse pluripotent stem cells were originallyderived from the inner cell mass (ICM) of blastocystsand shown to be the in vitro equivalent of those preimplantationembryonic cells, and thus were calledembryonic stem cells (ESCs). More than a decade later,pluripotent cells were isolated from the ICM of humanblastocysts. Despite being called human ESCs, thesecells differ significantly from mouse ESCs, includingdifferent morphology and mechanisms of control ofpluripotency, suggesting distinct embryonic originsof ESCs from the two species. Subsequently, mousepluripotent stem cells were established from the ICMderivedepiblast of post-implantation embryos. Thesemouse epiblast stem cells (EpiSCs) are morphologicaland epigenetically more similar to human ESCs. Thisraised the question of whether cells from the humanICM are in a more advanced differentiation stage thantheir murine counterpart, or whether the availableculture conditions were not adequate to maintain thosehuman cells in their in vivo state, leading to a transitioninto EpiSC-like cells in vitro . More recently, novel cultureconditions allowed the conversion of human ESCs intomouse ESC-like cells called naive (or ground state)human ESCs, and the derivation of naive human ESCsfrom blastocysts. Here we will review the characteristicsof each type of pluripotent stem cells, how (andwhether) these relate to different stages of embryonicdevelopment, and discuss the potential implications ofnaive human ESCs in research and therapy.

  16. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of clonogenic cells present among the bone marrow stroma and capable of multilineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. Due to their ease of isolation and their differentiation potential, MSC are being...... introduced into clinical medicine in variety of applications and through different ways of administration. Here, we discuss approaches for isolation, characterization and directing differentiation of human mesenchymal stem cells (hMSC). An update of the current clinical use of the cells is also provided....

  17. Dynamic changes in gene expression during human early embryo development: from fundamental aspects to clinical applications.

    Science.gov (United States)

    Assou, Said; Boumela, Imène; Haouzi, Delphine; Anahory, Tal; Dechaud, Hervé; De Vos, John; Hamamah, Samir

    2011-01-01

    The first week of human embryonic development comprises a series of events that change highly specialized germ cells into undifferentiated human embryonic stem cells (hESCs) that display an extraordinarily broad developmental potential. The understanding of these events is crucial to the improvement of the success rate of in vitro fertilization. With the emergence of new technologies such as Omics, the gene expression profiling of human oocytes, embryos and hESCs has been performed and generated a flood of data related to the molecular signature of early embryo development. In order to understand the complex genetic network that controls the first week of embryo development, we performed a systematic review and study of this issue. We performed a literature search using PubMed and EMBASE to identify all relevant studies published as original articles in English up to March 2010 (n = 165). We also analyzed the transcriptome of human oocytes, embryos and hESCs. Distinct sets of genes were revealed by comparing the expression profiles of oocytes, embryos on Day 3 and hESCs, which are associated with totipotency, pluripotency and reprogramming properties, respectively. Known components of two signaling pathways (WNT and transforming growth factor-β) were linked to oocyte maturation and early embryonic development. Omics analysis provides tools for understanding the molecular mechanisms and signaling pathways controlling early embryonic development. Furthermore, we discuss the clinical relevance of using a non-invasive molecular approach to embryo selection for the single-embryo transfer program.

  18. Human embryonic stem cells and respect for life

    OpenAIRE

    Meyer, J.(CERN, Geneva, Switzerland)

    2000-01-01

    The purpose of this essay is to stimulate academic discussion about the ethical justification of using human primordial stem cells for tissue transplantation, cell replacement, and gene therapy. There are intriguing alternatives to using embryos obtained from elective abortions and in vitro fertilisation to reconstitute damaged or dysfunctional human organs. These include the expansion and transplantation of latent adult progenitor cells.

  19. Political interventions in U.S. human embryo research: an ethical assessment.

    Science.gov (United States)

    Green, Ronald M

    2010-01-01

    For more than 30 years, beginning with the Reagan administration's refusal to support and provide oversight for embryo research, and continuing to the present in congressionally imposed limits on funding for such research, progress in infertility medicine and the development of stem cell therapies has been seriously delayed by a series of political interventions. In almost all cases, these interventions result from a view of the moral status of human embryo premised largely on religious assumptions. Although some believe that these interventions are valid expressions of religious values in the public sector, it is argued here that they, in fact, contradict Rawls's conception of public reasoning. Both the prohibition of research involving the human embryo as well as bans on federal funding for embryo-related research place the particular religious views of some citizens above the pressing health needs of almost all, and thus violate the ideal of civility implicit in the Rawlsian standard.

  20. The fate of the mosaic embryo : chromosomal constitution and development of Day 4, 5 and 8 human embryos

    NARCIS (Netherlands)

    Santos, Margarida Avo; Teklenburg, Gijs; Macklon, Nick S.; Van Opstal, Diane; Schuring-Blom, G. Heleen; Krijtenburg, Pieter-Jaap; de Vreeden-Elbertse, Johanna; Fauser, Bart C.; Baart, Esther B.

    2010-01-01

    Post-zygotic chromosome segregation errors are very common in human embryos after in vitro fertilization, resulting in mosaic embryos. However, the significance of mosaicism for the developmental potential of early embryos is unknown. We assessed chromosomal constitution and development of embryos f

  1. The human embryo in the Christian tradition: a reconsideration.

    Science.gov (United States)

    Jones, D A

    2005-12-01

    Recent claims that the Christian tradition justifies destructive research on human embryos have drawn upon an article by the late Professor Gordon Dunstan which appeared in this journal in 1984. Despite its undoubted influence, this article was flawed and seriously misrepresented the tradition of Christian reflection on the moral status of the human embryo.

  2. Cryopreservation of Oocytes and Embryos in Human Assisted Reproduction

    Directory of Open Access Journals (Sweden)

    Konc J

    2005-01-01

    Full Text Available Cryopreservation has become an integral component of assisted reproductive technology. The ability to cryopreserve, thaw, and establish pregnancies with supernumerary preimplantation embryos has become an important tool in fertility treatment. Human oocyte cryopreservation has practical application in preserving fertility for individuals prior to cancer treatments. While the efficiency of oocyte and embryo freezing technology has increased over time, there is still room for improvement, since even under ideal circumstances the clinical pregnancy rate from frozen embryo transfer is approximately two-thirds of that from the fresh transfer of embryos. Thus, studies connected with cryopreservation of human oocytes and embryos are very important to the expansion of effective clinical services. This review gives a summary of the theoretical and technical aspects of oocyte and embryo cryopreservation.

  3. Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo

    Science.gov (United States)

    Xue, Binghua; Li, Yan; He, Yilong; Wei, Renyue; Sun, Ruizhen; Yin, Zhi; Bou, Gerelchimeg; Liu, Zhonghua

    2016-01-01

    Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC) line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP) positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs) could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs. PMID:26991423

  4. Porcine Pluripotent Stem Cells Derived from IVF Embryos Contribute to Chimeric Development In Vivo.

    Directory of Open Access Journals (Sweden)

    Binghua Xue

    Full Text Available Although the pig is considered an important model of human disease and an ideal animal for the preclinical testing of cell transplantation, the utility of this model has been hampered by a lack of genuine porcine embryonic stem cells. Here, we derived a porcine pluripotent stem cell (pPSC line from day 5.5 blastocysts in a newly developed culture system based on MXV medium and a 5% oxygen atmosphere. The pPSCs had been passaged more than 75 times over two years, and the morphology of the colony was similar to that of human embryonic stem cells. Characterization and assessment showed that the pPSCs were alkaline phosphatase (AKP positive, possessed normal karyotypes and expressed classic pluripotent markers, including OCT4, SOX2 and NANOG. In vitro differentiation through embryonic body formation and in vivo differentiation via teratoma formation in nude mice demonstrated that the pPSCs could differentiate into cells of the three germ layers. The pPSCs transfected with fuw-DsRed (pPSC-FDs could be passaged with a stable expression of both DsRed and pluripotent markers. Notably, when pPSC-FDs were used as donor cells for somatic nuclear transfer, 11.52% of the reconstructed embryos developed into blastocysts, which was not significantly different from that of the reconstructed embryos derived from porcine embryonic fibroblasts. When pPSC-FDs were injected into day 4.5 blastocysts, they became involved in the in vitro embryonic development and contributed to the viscera of foetuses at day 50 of pregnancy as well as the developed placenta after the chimeric blastocysts were transferred into recipients. These findings indicated that the pPSCs were porcine pluripotent cells; that this would be a useful cell line for porcine genetic engineering and a valuable cell line for clarifying the molecular mechanism of pluripotency regulation in pigs.

  5. [Medical, ethical and legal issues in cryopreservation of human embryos].

    Science.gov (United States)

    Beca, Juan Pablo; Lecaros, Alberto; González, Patricio; Sanhueza, Pablo; Mandakovic, Borislava

    2014-07-01

    Embryo cryopreservation improves efficiency and security of assisted reproduction techniques. Nonetheless, it can be questionable, so it must be justified from technical, legal and ethical points of view. This article analyses these perspectives. Embryo cryopreservation maximizes the probability of pregnancy, avoids new ovary stimulations and reduces the occurrence of multiple gestations. There is consensus that the in vitro embryo deserves legal protection by its own, although not as a newborn. Very few countries prohibit embryo cryopreservation based on the legal duty to protect human life since fecundation. Those countries that allow it, privilege women's reproductive rights. In Chile and in Latin America, no laws have been promulgated to regulate human assisted reproduction. The moral status of the embryo depends on how it is considered. Some believe it is a potential person while others think it is just a group of cells, but all recognize that it requires some kind of respect and protection. There is lack of information about the number of frozen embryos and their final destination. As a conclusion the authors propose that women or couples should have the right to decide autonomously, while institutions ought to be clear in their regulations. And the legislation must establish the legal status of the embryo before its implantation, the couples' rights and the regulation of the embryo cryopreservation. Personal, institutional or legal decisions must assume a concept about the moral status of the human embryo and try to avoid their destruction or indefinite storage.

  6. Investigation of DNA repair in human oocytes and preimplantation embryos

    OpenAIRE

    Jaroudi, S.

    2010-01-01

    DNA repair genes are expressed in mammalian embryos and in human germinal vesicles, however, little is known about DNA repair in human preimplantation embryos. This project had three aims: 1) to produce a DNA repair profile of human MII oocytes and blastocysts using expression arrays and identify repair pathways that may be active before and after embryonic genome activation; 2) to design an in vitro functional assay that targeted mismatch repair and which could be applied to human oocytes...

  7. Expression of connexins in human preimplantation embryos in vitro

    Directory of Open Access Journals (Sweden)

    Leese Henry J

    2004-06-01

    Full Text Available Abstract Intercellular communication via gap junctions is required to coordinate developmental processes in the mammalian embryo. We have investigated if the connexin (Cx isoforms known to form gap junctions in rodent preimplantation embryos are also expressed in human embryos, with the aim of identifying species differences in communication patterns in early development. Using a combination of polyA PCR and immunocytochemistry we have assessed the expression of Cx26, Cx31, Cx32, Cx40, Cx43 and Cx45 which are thought to be important in early rodent embryos. The results demonstrate that Cx31 and Cx43 are the main connexin isoforms expressed in human preimplantation embryos and that these isoforms are co-expressed in the blastocyst. Cx45 protein is expressed in the blastocyst but the protein may be translated from a generally low level of transcripts: which could only be detected in the PN to 4-cell embryos. Interestingly, Cx40, which is expressed by the extravillous trophoblast in the early human placenta, was not found to be expressed in the blastocyst trophectoderm from which this tissue develops. All of the connexin isoforms in human preimplantation embryos are also found in rodents pointing to a common regulation of these connexins in development of rodent and human early embryos and perhaps other species.

  8. Genetic modification of preimplantation embryos: toward adequate human research policies.

    Science.gov (United States)

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo modification proposals might not receive adequate scientific and ethical scrutiny. This article describes current policy shortcomings and recommends policy actions designed to ensure that the investigational genetic modification of embryos meets accepted standards for research on human subjects.

  9. Global gene expression profiling of individual human oocytes and embryos demonstrates heterogeneity in early development.

    Directory of Open Access Journals (Sweden)

    Lisa Shaw

    Full Text Available Early development in humans is characterised by low and variable embryonic viability, reflected in low fecundity and high rates of miscarriage, relative to other mammals. Data from assisted reproduction programmes provides additional evidence that this is largely mediated at the level of embryonic competence and is highly heterogeneous among embryos. Understanding the basis of this heterogeneity has important implications in a number of areas including: the regulation of early human development, disorders of pregnancy, assisted reproduction programmes, the long term health of children which may be programmed in early development, and the molecular basis of pluripotency in human stem cell populations. We have therefore investigated global gene expression profiles using polyAPCR amplification and microarray technology applied to individual human oocytes and 4-cell and blastocyst stage embryos. In order to explore the basis of any variability in detail, each developmental stage is replicated in triplicate. Our data show that although transcript profiles are highly stage-specific, within each stage they are relatively variable. We describe expression of a number of gene families and pathways including apoptosis, cell cycle and amino acid metabolism, which are variably expressed and may be reflective of embryonic developmental competence. Overall, our data suggest that heterogeneity in human embryo developmental competence is reflected in global transcript profiles, and that the vast majority of existing human embryo gene expression data based on pooled oocytes and embryos need to be reinterpreted.

  10. The impact of preimplantation genetic diagnosis on human embryos

    Directory of Open Access Journals (Sweden)

    García-Ferreyra J.

    2016-12-01

    Full Text Available Chromosome abnormalities are extremely common in human oocytes and embryos and are associated with a variety of negative outcomes for both natural cycles and those using assisted reproduction techniques. Aneuploidies embryos may fail to implant in the uterus, miscarry, or lead to children with serious medical problems (e.g., Down syndrome. Preimplantation genetic diagnosis (PGD is a technique that allows the detection of aneuploidy in embryos and seeks to improve the clinical outcomes od assisted reproduction treatments, by ensuring that the embryos chosen for the transfer are chromosomally normal.

  11. Morphometric analysis of human embryos to predict developmental competence

    DEFF Research Database (Denmark)

    Ziebe, Søren

    2013-01-01

    , but rather choosing and prioritising between the available embryos. Data suggest that only approximately 5% of aspirated human oocytes have the competence to implant and develop into a child and that, in most treatment cycles, there is no oocyte capable of implanting. The most likely outcome is a negative......Morphometric and morphokinetic approaches toward embryo quality assessment have for many years been difficult due to technical limitations. Today, with improvements in laboratory techniques and subsequent quality, we have a better understanding of the morphometric and kinetics of embryo development....... Fertility clinics are moving from "sensing" embryo quality to measuring embryo quality--and this is happening every day in fertility clinics all over the world. However, we cannot select for something that is not there. In daily clinical life it is almost never a question of selecting the optimal embryo...

  12. Microfluidic protocol for in vitro culture of human embryos

    NARCIS (Netherlands)

    Hao, Zhenxia; Kieslinger, D.C.; Vergouw, C.; Kostelijk, H.; Lambalk, C.B.; Le Gac, S.; Zengerle, R.

    2013-01-01

    In vitro culture of pre-implantation embryos is a key-step in Assisted Reproductive Technologies (ART) protocols. In present work we examine the potential of microfluidic devices for pre-implantation human embryo culture, in comparison with conventional droplet-based culture (control). Donated froze

  13. Chromosomal mosaicism in human preimplantation embryos : a systematic review

    NARCIS (Netherlands)

    van Echten-Arends, Jannie; Mastenbroek, Sebastiaan; Sikkema-Raddatz, Birgit; Korevaar, Johanna C.; Heineman, Maas Jan; van der Veen, Fulco; Repping, Sjoerd

    2011-01-01

    BACKGROUND: Although chromosomal mosaicism in human preimplantation embryos has been described for almost two decades, its exact prevalence is still unknown. The prevalence of mosaicism is important in the context of preimplantation genetic screening in which the chromosomal status of an embryo is d

  14. Chromosomal mosaicism in human preimplantation embryos: a systematic review.

    NARCIS (Netherlands)

    Echten-Arends, J. van; Mastenbroek, S.; Sikkema-Raddatz, B.; Korevaar, J.C.; Heineman, M.J.; Veen, F. van der; Repping, S.

    2011-01-01

    BACKGROUND: Although chromosomal mosaicism in human preimplantation embryos has been described for almost two decades, its exact prevalence is still unknown. The prevalence of mosaicism is important in the context of preimplantation genetic screening in which the chromosomal status of an embryo is d

  15. Derivation of a Homozygous Human Androgenetic Embryonic Stem Cell Line.

    Science.gov (United States)

    Ding, Chenhui; Huang, Sunxing; Qi, Quan; Fu, Rui; Zhu, Wanwan; Cai, Bing; Hong, Pingping; Liu, Zhengxin; Gu, Tiantian; Zeng, Yanhong; Wang, Jing; Xu, Yanwen; Zhao, Xiaoyang; Zhou, Qi; Zhou, Canquan

    2015-10-01

    Human embryonic stem cells (hESCs) have long been considered as a promising source for cell replacement therapy. However, one major obstacle for the use of these cells is immune compatibility. Histocompatible human parthenogenetic ESCs have been reported as a new method for generating human leukocyte antigen (HLA)-matched hESCs. To further investigate the possibility of obtaining histocompatible stem cells from uniparental embryos, we tried to produce androgenetic haploid human embryos by injecting a single spermatozoon into enucleated human oocyte, and establish human androgenetic embryonic stem (hAGES) cell lines from androgenetic embryos. In the present study, a diploid hAGES cell line has been established, which exhibits typical features of human ESCs, including the expression of pluripotency markers, having differentiation potential in vitro and in vivo, and stable propagation in an undifferentiated state (>P40). Bisulfite sequencing of the H19, Snrpn, Meg3, and Kv imprinting control regions suggested that hAGES cells maintained to a certain extent a sperm methylation pattern. Genome-wide single nucleotide polymorphism, short tandem repeat, and HLA analyses revealed that the hAGES cell genome was highly homozygous. These results suggest that hAGES cells from spermatozoon could serve as a useful tool for studying the mechanisms underlying genomic imprinting in humans. It might also be used as a potential resource for cell replacement therapy as parthenogenetic stem cells.

  16. Genetic Modification of Preimplantation Embryos: Toward Adequate Human Research Policies

    OpenAIRE

    Dresser, Rebecca

    2004-01-01

    Citing advances in transgenic animal research and setbacks in human trials of somatic cell genetic interventions, some scientists and others want to begin planning for research involving the genetic modification of human embryos. Because this form of genetic modification could affect later-born children and their offspring, the protection of human subjects should be a priority in decisions about whether to proceed with such research. Yet because of gaps in existing federal policies, embryo mo...

  17. Autophagy in human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Thien Tra

    Full Text Available Autophagy (macroautophagy is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of embryoid bodies. The precise roles of autophagy during early human embryonic development, remain however largely uncharacterized. Since human embryonic stem cells constitute a unique model system to study early human embryogenesis we investigated the occurrence of autophagy in human embryonic stem cells. We have, using lentiviral transduction, established multiple human embryonic stem cell lines that stably express GFP-LC3, a fluorescent marker for the autophagosome. Each cell line displays both a normal karyotype and pluripotency as indicated by the presence of cell types representative of the three germlayers in derived teratomas. GFP expression and labelling of autophagosomes is retained after differentiation. Baseline levels of autophagy detected in cultured undifferentiated hESC were increased or decreased in the presence of rapamycin and wortmannin, respectively. Interestingly, autophagy was upregulated in hESCs induced to undergo differentiation by treatment with type I TGF-beta receptor inhibitor SB431542 or removal of MEF secreted maintenance factors. In conclusion we have established hESCs capable of reporting macroautophagy and identify a novel link between autophagy and early differentiation events in hESC.

  18. Arrested human embryos are more likely to have abnormal chromosomes than developing embryos from women of advanced maternal age.

    Science.gov (United States)

    Qi, Shu-Tao; Liang, Li-Feng; Xian, Ye-Xing; Liu, Jian-Qiao; Wang, Weihua

    2014-01-01

    Aneuploidy is one of the major factors that result in low efficiency in human infertility treatment by in vitro fertilization (IVF). The development of DNA microarray technology allows for aneuploidy screening by analyzing all 23 pairs of chromosomes in human embryos. All chromosome screening for aneuploidy is more accurate than partial chromosome screening, as errors can occur in any chromosome. Currently, chromosome screening for aneuploidy is performed in developing embryos, mainly blastocysts. It has not been performed in arrested embryos and/or compared between developing embryos and arrested embryos from the same IVF cycle. The present study was designed to examine all chromosomes in blastocysts and arrested embryos from the same cycle in patients of advanced maternal ages. Embryos were produced by routine IVF procedures. A total of 90 embryos (45 blastocysts and 45 arrested embryos) from 17 patients were biopsied and analyzed by the Agilent DNA array platform. It was found that 50% of the embryos developed to blastocyst stage; however, only 15.6% of the embryos (both blastocyst and arrested) were euploid, and most (84.4%) of the embryos had chromosomal abnormalities. Further analysis indicated that 28.9% of blastocysts were euploid and 71.1% were aneuploid. By contrast, only one (2.2%) arrested embryo was euploid while others (97.8%) were aneuploid. The prevalence of multiple chromosomal abnormalities in the aneuploid embryos was also higher in the arrested embryos than in the blastocysts. These results indicate that high proportions of human embryos from patients of advanced maternal age are aneuploid, and the arrested embryos are more likely to have abnormal chromosomes than developing embryos.

  19. [The human embryo after Dolly: new practices for new times].

    Science.gov (United States)

    de Miguel Beriain, Iñigo

    2008-01-01

    The possiblity of cloning human beings introduced a lot of issues in our ethical and legal frameworks. In this paper, we will put the focus into the necessary changes in the concept of embryo that our legal systems will have to implement in order to face the new situation. The description of the embryo as a group of cells able to develop into a human being will be defended here as the best way of doing so.

  20. HLA-matched embryos selected for siblings requiring haematopoietic stem cell transplantation: a psychological perspective.

    Science.gov (United States)

    Baetens, P; Van de Velde, H; Camus, M; Pennings, G; van Steirteghem, A; Devroey, P; Liebaers, I

    2005-02-01

    Allogeneic haematopoietic stem cell transplantation (HSCT) is a treatment for a number of acquired and congenital diseases. An important factor in the outcome of the treatment is the degree of human leukocyte antigen (HLA) compatibility between patient and donor. HLA identical siblings therefore provide the best chance for the recipient. Preimplantation genetic diagnosis (PGD) can be used to select HLA identical embryos if there is no HLA compatible sibling in the family. The Centre for Reproductive Medicine considered it morally justified to give medical assistance to couples in need of an HLA matched sibling. Two considerations played an important role in this respect: (i) the use as a donor should not be the only parents' motive for having the child and (ii) IVF and HLA typing on the embryos would be less of a burden for the parents than other alternatives. Since the first request in 2000, 12 couples have been referred for psychological counselling. The motivation of four couples will be discussed in depth. The validity of the arguments will be checked against the experience of the actual cases. The consequences of the treatment on the welfare of the future donor child will be discussed.

  1. The fate of the mosaic embryo: Chromosomal constitution and development of Day 4, 5 and 8 human embryos

    NARCIS (Netherlands)

    M.A. Santos; G. Teklenburg (Gijs); N.S. Macklon (Nick); D. van Opstal (Diane); G.H. Schuring-Blom (Heleen); P-J. Krijtenburg (Pieter-Jaap); J. de Vreeden-Elbertse (Johanna); B.C.J.M. Fauser (Bart); E.B. Baart (Esther)

    2010-01-01

    textabstractBackground: Post-zygotic chromosome segregation errors are very common in human embryos after in vitro fertilization, resulting in mosaic embryos. However, the significance of mosaicism for the developmental potential of early embryos is unknown. We assessed chromosomal constitution and

  2. Human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Aldahmash, Abdullah; Zaher, Walid; Al-Nbaheen, May

    2012-01-01

    Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self-renewal and......Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self...... of clinical applications, e.g., non-healing bone fractures and defects and also non-skeletal degenerative diseases like heart failure. Currently, the numbers of clinical trials that employ MSC are increasing. However, several biological and biotechnological challenges need to be overcome to benefit from...

  3. The genetic heterozygosity and fitness of tetraploid embryos and embryonic stem cells are crucial parameters influencing survival of mice derived from embryonic stem cells by tetraploid embryo aggregation.

    Science.gov (United States)

    Li, Xiangyun; Wei, Wei; Yong, Jun; Jia, Qing; Yu, Yuansong; Di, Keqian

    2005-07-01

    The aim of this paper was to determine whether the genetic background of tetraploid embryos contributed to the survival of mice derived from embryonic stem (ES) cells by tetraploid embryo complementation. Twenty-five newborns were produced by aggregation of hybrid ES cells and tetraploid embryos with different genetic backgrounds. These newborns were entirely derived from ES cells judged by microsatellite DNA (A specific sequence of DNA bases or nucleotides that contains mono, di, tri or tetra repeats) and coat colour phenotype and germline transmission. Fifteen survived to adulthood while seven died of respiratory failure. All newborns were derived from outbred or hybrid tetraploid aggregates and no newborns were from the inbreds. Our results demonstrate that the genetic heterozygosity, fitness of tetraploid embryos and fitness of ES cells are crucial parameters influencing survival of mice derived from ES cells by tetraploid embryo aggregation. In addition, this method represents a simple and efficient procedure for immediate generation of targeted mouse mutants from genetically modified ES cell clones, in contrast to the standard protocol, which involves the production of chimeras and several breeding steps.

  4. The endometrial factor in human embryo implantation

    NARCIS (Netherlands)

    Boomsma, C.M.

    2009-01-01

    The studies presented in this thesis aimed to explore the role of the endometrium in the implantation process. At present, embryo implantation is the major rate-limiting step for success in fertility treatment. Clinicians have sought to develop clinical interventions aimed at enhancing implantation

  5. The endometrial factor in human embryo implantation

    NARCIS (Netherlands)

    Boomsma, C.M.

    2009-01-01

    The studies presented in this thesis aimed to explore the role of the endometrium in the implantation process. At present, embryo implantation is the major rate-limiting step for success in fertility treatment. Clinicians have sought to develop clinical interventions aimed at enhancing implantation

  6. β-catenin functions pleiotropically in differentiation and tumorigenesis in mouse embryo-derived stem cells.

    Directory of Open Access Journals (Sweden)

    Noriko Okumura

    Full Text Available The canonical Wnt/β-catenin signaling pathway plays a crucial role in the maintenance of the balance between proliferation and differentiation throughout embryogenesis and tissue homeostasis. β-Catenin, encoded by the Ctnnb1 gene, mediates an intracellular signaling cascade activated by Wnt. It also plays an important role in the maintenance of various types of stem cells including adult stem cells and cancer stem cells. However, it is unclear if β-catenin is required for the derivation of mouse embryo-derived stem cells. Here, we established β-catenin-deficient (β-cat(Δ/Δ mouse embryo-derived stem cells and showed that β-catenin is not essential for acquiring self-renewal potential in the derivation of mouse embryonic stem cells (ESCs. However, teratomas formed from embryo-derived β-cat(Δ/Δ ESCs were immature germ cell tumors without multilineage differentiated cell types. Re-expression of functional β-catenin eliminated their neoplastic, transformed phenotype and restored pluripotency, thereby rescuing the mutant ESCs. Our findings demonstrate that β-catenin has pleiotropic effects in ESCs; it is required for the differentiation of ESCs and prevents them from acquiring tumorigenic character. These results highlight β-catenin as the gatekeeper in differentiation and tumorigenesis in ESCs.

  7. Definitive hematopoietic stem cells first develop within the major arterial regions of the mouse embryo.

    NARCIS (Netherlands)

    M.F.T.R. de Bruijn (Marella); N.A. Speck; M.C. Peeters (Marian); E.A. Dzierzak (Elaine)

    2000-01-01

    textabstractThe aorta-gonad-mesonephros (AGM) region is a potent hematopoietic site within the mammalian embryo body, and the first place from which hematopoietic stem cells (HSCs) emerge. Within the complex embryonic vascular, excretory and reproductive tissues of the

  8. Parameters influencing derivation of embryonic stem cells from murine embryos.

    Science.gov (United States)

    Batlle-Morera, Laura; Smith, Austin; Nichols, Jennifer

    2008-12-01

    The derivation of ES cells is poorly understood and varies in efficiency between different strains of mice. We have investigated potential differences between embryos of permissive and recalcitrant strains during diapause and ES cell derivation. We found that in diapause embryos of the recalcitrant C57BL/6 and CBA strains, the epiblast failed to expand during the primary explant phase of ES cell derivation, whereas in the permissive 129 strain, it expanded dramatically. Epiblasts from the recalcitrant strains could be expanded by reducing Erk activation. Isolation of 129 epiblasts facilitated very efficient derivation of ES cell lines in serum- and feeder-free conditions, but reduction of Erk activity was required for derivation of ES cells from isolated C57BL/6 or CBA epiblasts. The results suggest that the discrepancy in ES cell derivation efficiency is not attributable merely to variable prodifferentiative effects of the extra-embryonic lineages but also to an intrinsic variability within the epiblast to maintain pluripotency.

  9. In Vivo Differentiation Potential of Epiblast Stem Cells Revealed by Chimeric Embryo Formation

    Directory of Open Access Journals (Sweden)

    Yali Huang

    2012-12-01

    Full Text Available Chimera formation after blastocyst injection or morula aggregation is the principal functional assay of the developmental potential of mouse embryonic stem cells (ESCs. This property, which demonstrates functional equivalence between ESCs and the preimplantation epiblast, is not shared by epiblast stem cell (EpiSC lines. Here, we show that EpiSCs derived either from postimplantation embryos or from ESCs in vitro readily generate chimeras when grafted to postimplantation embryos in whole embryo culture. EpiSC derivatives integrate and differentiate to derivatives of all three embryonic germ layers and primordial germ cells. In contrast, grafted ESCs seldom proliferate in postimplantation embryos, and fail to acquire the identity of their host-derived neighbors. EpiSCs do not incorporate efficiently into embryonic day 8.5 embryos, a stage by which pluripotency has been lost. Thus, chimera formation by EpiSCs requires a permissive environment, the postimplantation epiblast, and demonstrates functional equivalence between this cell type and EpiSCs.

  10. Isolation, identification and differentiation of human embryonic cartilage stem cells.

    Science.gov (United States)

    Fu, Changhao; Yan, Zi; Xu, Hao; Zhang, Chen; Zhang, Qi; Wei, Anhui; Yang, Xi; Wang, Yi

    2015-07-01

    We isolated human embryonic cartilage stem cells (hECSCs), a novel stem cell population, from the articular cartilage of eight-week-old human embryos. These stem cells demonstrated a marker expression pattern and differentiation potential intermediate to those of human embryonic stem cells (hESCs) and human adult stem cells (hASCs). hECSCs expressed markers associated with both hESCs (OCT4, NANOG, SOX2, SSEA-3 and SSEA-4) and human adult stem cells (hASCs) (CD29, CD44, CD90, CD73 and CD10). These cells also differentiated into adipocytes, osteoblasts, chondrocytes, neurons and islet-like cells under specific inducing conditions. We identified N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) as an inducer of chondrogenic differentiation in hECSCs. Similar results using N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) were obtained for two other types of human embryonic tissue-derived stem cells, human embryonic hepatic stem cells (hEHSCs) and human embryonic amniotic fluid stem cells (hEASCs), both of which exhibited a marker expression pattern similar to that of hECSCs. The isolation of hECSCs and the discovery that N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) induces chondrogenic differentiation in different stem cell populations might aid the development of strategies in tissue engineering and cartilage repair.

  11. X-chromosome inactivation in monkey embryos and pluripotent stem cells.

    Science.gov (United States)

    Tachibana, Masahito; Ma, Hong; Sparman, Michelle L; Lee, Hyo-Sang; Ramsey, Cathy M; Woodward, Joy S; Sritanaudomchai, Hathaitip; Masterson, Keith R; Wolff, Erin E; Jia, Yibing; Mitalipov, Shoukhrat M

    2012-11-15

    Inactivation of one X chromosome in female mammals (XX) compensates for the reduced dosage of X-linked gene expression in males (XY). However, the inner cell mass (ICM) of mouse preimplantation blastocysts and their in vitro counterparts, pluripotent embryonic stem cells (ESCs), initially maintain two active X chromosomes (XaXa). Random X chromosome inactivation (XCI) takes place in the ICM lineage after implantation or upon differentiation of ESCs, resulting in mosaic tissues composed of two cell types carrying either maternal or paternal active X chromosomes. While the status of XCI in human embryos and ICMs remains unknown, majority of human female ESCs show non-random XCI. We demonstrate here that rhesus monkey ESCs also display monoallelic expression and methylation of X-linked genes in agreement with non-random XCI. However, XIST and other X-linked genes were expressed from both chromosomes in isolated female monkey ICMs indicating that ex vivo pluripotent cells retain XaXa. Intriguingly, the trophectoderm (TE) in preimplantation monkey blastocysts also expressed X-linked genes from both alleles suggesting that, unlike the mouse, primate TE lineage does not support imprinted paternal XCI. Our results provide insights into the species-specific nature of XCI in the primate system and reveal fundamental epigenetic differences between in vitro and ex vivo primate pluripotent cells.

  12. Human embryonic stem cells derived by somatic cell nuclear transfer.

    Science.gov (United States)

    Tachibana, Masahito; Amato, Paula; Sparman, Michelle; Gutierrez, Nuria Marti; Tippner-Hedges, Rebecca; Ma, Hong; Kang, Eunju; Fulati, Alimujiang; Lee, Hyo-Sang; Sritanaudomchai, Hathaitip; Masterson, Keith; Larson, Janine; Eaton, Deborah; Sadler-Fredd, Karen; Battaglia, David; Lee, David; Wu, Diana; Jensen, Jeffrey; Patton, Phillip; Gokhale, Sumita; Stouffer, Richard L; Wolf, Don; Mitalipov, Shoukhrat

    2013-06-06

    Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state.

  13. Leukemia inhibitory factor (LIF)-dependent, pluripotent stem cells established from inner cell mass of porcine embryos.

    Science.gov (United States)

    Telugu, Bhanu Prakash V L; Ezashi, Toshihiko; Sinha, Sunilima; Alexenko, Andrei P; Spate, Lee; Prather, Randall S; Roberts, R Michael

    2011-08-19

    The pig is important for agriculture and as an animal model in human and veterinary medicine, yet despite over 20 years of effort, there has been a failure to generate pluripotent stem cells analogous to those derived from mouse embryos. Here we report the production of leukemia inhibitory factor-dependent, so-called naive type, pluripotent stem cells from the inner cell mass of porcine blastocysts by up-regulating expression of KLF4 and POU5F1. The alkaline phosphatase-positive colonies resulting from reprogramming resemble mouse embryonic stem cells in colony morphology, cell cycle interval, transcriptome profile, and expression of pluripotent markers, such as POU5F1, SOX2, and surface marker SSEA1. They are dependent on leukemia inhibitory factor signaling for maintenance of pluripotency, can be cultured over extended passage, and have the ability to form teratomas. These cells derived from the inner cell mass of pig blastocysts are clearly distinct from the FGF2-dependent "primed" induced pluripotent stem cells described recently from porcine mesenchymal cells. The data are consistent with the hypothesis that the up-regulation of KLF4, as well as POU5F1, is required to create and stabilize the naive pluripotent state and may explain why the derivation of embryonic stem cells from pigs and other ungulates has proved so difficult.

  14. Derivation of the human embryonic stem cell line RCe012-A (RC-8)

    OpenAIRE

    P.A. De Sousa; B.J. Tye; Bruce, K.; P. Dand; RUSSELL, G.; Collins, D. M.; Greenshields, A.; H. Bradburn; J.M. Downie; M. Bateman; A. Courtney

    2016-01-01

    The human embryonic stem cell line RCe012-A (RC-8) was derived from a frozen and thawed day 5 embryo cultivated to the blastocyst stage. The embryo was voluntarily donated as unsuitable and surplus to fertility requirements following ethics committee approved informed consent under licence from the UK Human Fertilisation and Embryology Authority. The cell line shows normal pluripotency marker expression and differentiation to the three germ layers in vitro. It has a normal 46XX female karyoty...

  15. Molecular biology of the stress response in the early embryo and its stem cells.

    Science.gov (United States)

    Puscheck, Elizabeth E; Awonuga, Awoniyi O; Yang, Yu; Jiang, Zhongliang; Rappolee, Daniel A

    2015-01-01

    Stress is normal during early embryogenesis and transient, elevated stress is commonplace. Stress in the milieu of the peri-implantation embryo is a summation of maternal hormones, and other elements of the maternal milieu, that signal preparedness for development and implantation. Examples discussed here are leptin, adrenaline, cortisol, and progesterone. These hormones signal maternal nutritional status and provide energy, but also signal stress that diverts maternal and embryonic energy from an optimal embryonic developmental trajectory. These hormones communicate endocrine maternal effects and local embryonic effects although signaling mechanisms are not well understood. Other in vivo stresses affect the embryo such as local infection and inflammation, hypoxia, environmental toxins such as benzopyrene, dioxin, or metals, heat shock, and hyperosmotic stress due to dehydration or diabetes. In vitro, stresses include shear during handling, improper culture media and oxygen levels, cryopreservation, and manipulations of the embryo to introduce sperm or mitochondria. We define stress as any stimulus that slows stem cell accumulation or diminishes the ability of cells to produce normal and sufficient parenchymal products upon differentiation. Thus stress deflects downwards the normal trajectories of development, growth and differentiation. Typically stress is inversely proportional to embryonic developmental and proliferative rates, but can be proportional to induction of differentiation of stem cells in the peri-implantation embryo. When modeling stress it is most interesting to produce a 'runting model' where stress exposures slow accumulation but do not create excessive apoptosis or morbidity. Windows of stress sensitivity may occur when major new embryonic developmental programs require large amounts of energy and are exacerbated if nutritional flow decreases and removes energy from the normal developmental programs and stress responses. These windows correspond

  16. Reconstruction of human embryos derived from somatic cells

    Institute of Scientific and Technical Information of China (English)

    LU Changfu; LIN Ge; XIE Changqing; GONG Fei; ZHOU Hong; TAN Yueqiu; LU Guangxiu

    2003-01-01

    Reconstruction of human nuclear transfer embryos is a necessary step of therapeutic cloning. In this study we injected somatic cell nuclei into MⅡ oocytes and activated reconstructed oocytes with calcium ionophore A23187 (CaA) and 6-dimethylaminopurine (6-DMAP). After oocyte activation and 2PN formation, we removed the female PN. By using this method, we avoided the application of DNA fluorescent stain and ultraviolet light for oocyte enucleation, and over elimination of ooplasm was also mitigated. Some reconstructed embryos developed into theblastocyst stage in vitro.

  17. Passage number affects the pluripotency of mouse embryonic stem cells as judged by tetraploid embryo aggregation.

    Science.gov (United States)

    Li, Xiang-Yun; Jia, Qing; Di, Ke-Qian; Gao, Shu-Min; Wen, Xiao-Hui; Zhou, Rong-Yan; Wei, Wei; Wang, Li-Ze

    2007-03-01

    The aim of this study was to determine whether the number of passages affected the developmental pluripotency of embryonic stem (ES) cells as measured by the attainment of adult fertile mice derived from embryonic stem (ES) cell/tetraploid embryo complementation. Thirty-six newborns were produced by the aggregation of tetraploid embryos and hybrid ES cells after various numbers of passages. These newborns were entirely derived from ES cells as judged by microsatellite DNA, coat-color phenotype, and germline transmission. Although 15 survived to adulthood, 17 died of respiratory failure, and four were eaten by their foster mother. From the 15 mice that reached adulthood and that could reproduce, none arose from ES cells at passage level 15 or more. All 15 arose from cells at passages 3-11. Our results demonstrate that the number of passages affects the developmental pluripotency of ES cells.

  18. Embryonic stem cell as nuclear donor could promote in vitro development of the heterogeneous reconstructed embryo

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The nucleus of a somatic cell could be dedifferentiated and reprogrammed in an enucleated heterogeneous oocyte. Some reconstructed oocytes could develop into blastocysts in vitro, and a few could develop into term normally after transferred into foster mothers, but most of cloning embryos fail to develop to term. In order to evaluate the efficacy of embryonic stem cell as nucleus donor in interspecific animal cloning, we reconstructed enucleated rabbit oocytes with nuclei from mouse ES cells, and analyzed the developmental ability of reconstructed embryos in vitro. Two kinds of fibroblast cells were used as donor control, one derived from ear skin of an adult Kunming albino mouse, and the other derived from a mouse fetus. Three types of cells were transferred into perivitelline space under zona pellucida of rabbit oocytes respectively. The reconstructed oocytes were fused and activated by electric pulses, and cultured in vitro. The developmental rate of reconstructed oocytes derived from embryonic stem cells was 16.1%, which was significantly higher than that of both the adult mouse fibroblast cells (0%-3.1%, P < 0.05) and fetus mouse fibroblast cells (2.1%-3.7%, P < 0.05). Chromosome analysis confirmed that blastocyst cells were derived from ES donor cell. These observations show that reprogramming is easier in interspecific embryos reconstructed with ES cells than that reconstructed with somatic cells, and that ES cells have the higher ability to direct the reconstructed embryos development normally than fibroblast cells.

  19. Human embryonic stem cells carrying mutations for severe genetic disorders.

    Science.gov (United States)

    Frumkin, Tsvia; Malcov, Mira; Telias, Michael; Gold, Veronica; Schwartz, Tamar; Azem, Foad; Amit, Ami; Yaron, Yuval; Ben-Yosef, Dalit

    2010-04-01

    Human embryonic stem cells (HESCs) carrying specific mutations potentially provide a valuable tool for studying genetic disorders in humans. One preferable approach for obtaining these cell lines is by deriving them from affected preimplantation genetically diagnosed embryos. These unique cells are especially important for modeling human genetic disorders for which there are no adequate research models. They can be further used to gain new insights into developmentally regulated events that occur during human embryo development and that are responsible for the manifestation of genetically inherited disorders. They also have great value for the exploration of new therapeutic protocols, including gene-therapy-based treatments and disease-oriented drug screening and discovery. Here, we report the establishment of 15 different mutant human embryonic stem cell lines derived from genetically affected embryos, all donated by couples undergoing preimplantation genetic diagnosis in our in vitro fertilization unit. For further information regarding access to HESC lines from our repository, for research purposes, please email dalitb@tasmc.health.gov.il.

  20. Natural selection of human embryos: decidualizing endometrial stromal cells serve as sensors of embryo quality upon implantation.

    Directory of Open Access Journals (Sweden)

    Gijs Teklenburg

    Full Text Available BACKGROUND: Pregnancy is widely viewed as dependent upon an intimate dialogue, mediated by locally secreted factors between a developmentally competent embryo and a receptive endometrium. Reproductive success in humans is however limited, largely because of the high prevalence of chromosomally abnormal preimplantation embryos. Moreover, the transient period of endometrial receptivity in humans uniquely coincides with differentiation of endometrial stromal cells (ESCs into highly specialized decidual cells, which in the absence of pregnancy invariably triggers menstruation. The role of cyclic decidualization of the endometrium in the implantation process and the nature of the decidual cytokines and growth factors that mediate the crosstalk with the embryo are unknown. METHODOLOGY/PRINCIPAL FINDINGS: We employed a human co-culture model, consisting of decidualizing ESCs and single hatched blastocysts, to identify the soluble factors involved in implantation. Over the 3-day co-culture period, approximately 75% of embryos arrested whereas the remainder showed normal development. The levels of 14 implantation factors secreted by the stromal cells were determined by multiplex immunoassay. Surprisingly, the presence of a developing embryo had no significant effect on decidual secretions, apart from a modest reduction in IL-5 levels. In contrast, arresting embryos triggered a strong response, characterized by selective inhibition of IL-1beta, -6, -10, -17, -18, eotaxin, and HB-EGF secretion. Co-cultures were repeated with undifferentiated ESCs but none of the secreted cytokines were affected by the presence of a developing or arresting embryo. CONCLUSIONS: Human ESCs become biosensors of embryo quality upon differentiation into decidual cells. In view of the high incidence of gross chromosomal errors in human preimplantation embryos, cyclic decidualization followed by menstrual shedding may represent a mechanism of natural embryo selection that limits

  1. The procurement of cells for the derivation of human embryonic stem cell lines for therapeutic use: recommendations for good practice.

    Science.gov (United States)

    Murdoch, Alison; Braude, Peter; Courtney, Aidan; Brison, Daniel; Hunt, Charles; Lawford-Davies, James; Moore, Harry; Stacey, Glyn; Sethe, Sebastian

    2012-03-01

    The donation of human embryos for the derivation of embryonic stem cell lines that may be used in the development of therapeutic products raises more complex ethical, practical and regulatory problems than the donation of embryos for non-clinical research. This review considers these issues and offers recommendations for good practice.

  2. Addressing the ethical issues raised by synthetic human entities with embryo-like features

    Science.gov (United States)

    Aach, John; Lunshof, Jeantine; Iyer, Eswar; Church, George M

    2017-01-01

    The "14-day rule" for embryo research stipulates that experiments with intact human embryos must not allow them to develop beyond 14 days or the appearance of the primitive streak. However, recent experiments showing that suitably cultured human pluripotent stem cells can self-organize and recapitulate embryonic features have highlighted difficulties with the 14-day rule and led to calls for its reassessment. Here we argue that these and related experiments raise more foundational issues that cannot be fixed by adjusting the 14-day rule, because the framework underlying the rule cannot adequately describe the ways by which synthetic human entities with embryo-like features (SHEEFs) might develop morally concerning features through altered forms of development. We propose that limits on research with SHEEFs be based as directly as possible on the generation of such features, and recommend that the research and bioethics communities lead a wide-ranging inquiry aimed at mapping out solutions to the ethical problems raised by them. DOI: http://dx.doi.org/10.7554/eLife.20674.001

  3. Human embryonic stem cells handbook

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2013-03-01

    Full Text Available After the Nobel prize in physiology or medicine was awarded jointly to Sir John Gurdon and Shinya Yamanaka for the discovery that mature cells can be reprogrammed to become pluripotent it became imperative to write down the review for a book entirely devoted to human embryonic stem cells (hES, those cells that are a urgent need for researchers, those cells that rekindle the ethical debates and finally, last but not least, those cells whose study paved the way to obtain induced pluripotent stem cells by the OSKC’s Yamanaka method (the OSKC acronim refers, for those not familiar with the topic, to the four stemness genes used to transfect somatic fibroblasts: Oct4, Sox2, Klf4 and c-Myc....

  4. 人類胚胎幹細胞專利與胚胎保護 ― 一部 98/44/EC 指令各自表述 Human Embryonic Stem Cell Patent and Protection of Embryos Controversies Surrounding Directive 98/44/EC

    Directory of Open Access Journals (Sweden)

    陳英鈐 In-Chin Chen

    2006-06-01

    Full Text Available 許多專家相信,從早期胚胎取得的幹細胞最具彈性,可能導致生物醫學革命,甚至治療許多現今無可救藥的疾病。然而從胚胎取得幹細胞,可能摧毀胚胎。關於胚胎法律與道德地位的爭議,也深深影響著予胚胎幹細胞相關發明的可專利性。歐洲專利公約本即規定,發明之公開或商業利用違反公序良俗者,不與專利。被整合進歐洲專利公約的歐洲生物科技指令更例示,複製人類的方法、改變人類生殖系基因同一性的方法以及為產業或商業目的使用人類胚胎不與發明專利。歐洲專利局與審查與異議部門迄今採取相當嚴格態度,禁止一切與胚胎幹細胞相關的產品與方法專利,德國、英國與瑞士 則在不同程度上容許之。 本文認為,TRIPS 第27 條第2 項規定,生物科技的發明原則上亦具 有可專利性,因此公序良俗條款及其例示規定應從嚴解釋,相關爭議包括EGE 第16 號意見,應由此加以批判性地檢視。 Many experts believe that human embryonic stem cells may lead to medical revolution and treat a lot of hitherto incurable diseases. Since embryos may be destroyed in this process, the controversies over the legal and ethical status of human embryos are extended to, weather inventions involving human embryonic stem cells are patentable. Article 53 (a EPC excludes the patentability of inventions the publication or exploitation of which would be contrary to “ordre public” or morality. Directive 98/44/EC, integrated into the EPC implementing regulations, illustrates the following examples as not patentable: the processes for cloning human beings; processes for modifying the germ line genetic identity of human beings and uses of human embryos for industrial or commercial purposes. The Examining and Opposition Divisions of EPO exclude from patentability all inventions involving human embryonic stem cells. Since

  5. Differences in gene expression profiles between human preimplantation embryos cultured in two different IVF culture media

    NARCIS (Netherlands)

    Kleijkers, S.H.M.; Eijssen, L.M.T.; Coonen, E.; Derhaag, J.G.; Mantikou, E.; Jonker, M.J.; Mastenbroek, S.; Repping, S.; Evers, J.L.H.; Dumoulin, J.C.M.; van Montfoort, A.P.A.

    2015-01-01

    STUDY QUESTION: Is gene expression in human preimplantation embryos affected by the medium used for embryo culture in vitro during an IVF treatment? SUMMARY ANSWER: Six days of in vitro culture of human preimplantation embryos resulted in medium-dependent differences in expression level of genes inv

  6. Establishment and characterization of two new human embryonic stem cell lines, SYSU-1 and SYSU-2

    Institute of Scientific and Technical Information of China (English)

    HUANG Guo; Andy Peng Xiang; LI Wei-qiang; CHEN Rui; CHEN Zhen-guang; ZHANG Xiu-ming; MAO Fu-xiang; HUANG Shao-liang; LI Shu-nong; Bruce T Lahn

    2007-01-01

    Background Human embryonic stem cells can propagate indefinitely in vitro and are able to differentiate into derivatives of all three embryonic germ layers. The excitement surrounding human embryonic stem cells lies largely in their potential to produce specialized cells that can be used for transplant therapies. However, further investigation requires additional cell lines with varying genetic background. Therefore, efforts to derive and establish more human embryonic stem cell lines are highly warranted.Methods Surplus embryos (blastocysts) from donors were used to isolate the inner cell mass by immunosurgery. All cells were cultured continuously on irradiated murine embryonic fibroblasts feed layer and likely human embryonic stem cell colonies were subsequently characterized by cell surface marker staining, karyotyping and teratoma formation.Results Two human embryonic stem cell lines (SYSU-1 and SYSU-2) were established from surplus embryos. The two lines express several pluripotency markers including alkaline phosphatase, SSEA- 4, Tra-1-60, Oct-4, Nanog and Rex-1.They remain in undifferentiated state with normal karyotype after prolonged passages and can form embryoid bodies in vitro and teratoma in vivo.Conclusion Two new human embryonic stem cell lines have been established from surplus embryos. They can be used to understand selfrenewal and differentiating mechanisms and provide more choices for regenerative medicine.

  7. Generation of embryos directly from embryonic stem cells by tetraploid embryo complementation reveals a role for GATA factors in organogenesis.

    Science.gov (United States)

    Duncan, S A

    2005-12-01

    Gene targeting in ES (embryonic stem) cells has been used extensively to study the role of proteins during embryonic development. In the traditional procedure, this requires the generation of chimaeric mice by introducing ES cells into blastocysts and allowing them to develop to term. Once chimaeric mice are produced, they are bred into a recipient mouse strain to establish germline transmission of the allele of interest. Although this approach has been used very successfully, the breeding cycles involved are time consuming. In addition, genes that are essential for organogenesis often have roles in the formation of extra-embryonic tissues that are essential for early stages of post-implantation development. For example, mice lacking the GATA transcription factors, GATA4 or GATA6, arrest during gastrulation due to an essential role for these factors in differentiation of extra-embryonic endoderm. This lethality has frustrated the study of these factors during the development of organs such as the liver and heart. Extraembryonic defects can, however, be circumvented by generating clonal mouse embryos directly from ES cells by tetraploid complementation. Here, we describe the usefulness and efficacy of this approach using GATA factors as an example.

  8. Human embryonic stem cell research: implications from an ethical and legal standpoint.

    Science.gov (United States)

    Trepagnier, D M

    2000-12-01

    The purpose of this paper is to discuss the ethical and legal implications of one of the newest and most controversial medical breakthroughs. Stem cell research has been performed on mice for many years, but human embryonic stem cells are believed by scientists to be the basis for possible treatments and/or cures to many diseases affecting millions of people around the world. In order to perform research on human embryonic stem cells, numerous ethical issues must be addressed. Guidelines and protocols can be established in order to allow scientists to pursue new medical advances while maintaining the highest ethical standards in the use of human embryos. An alternative to using embryos is adult stem cells which have recently proven to be more versatile than previously believed. Opposing views will always be encountered when facing new science technologies. Where should the ethical line be drawn?

  9. Human cloning, stem cell research. An Islamic perspective.

    Science.gov (United States)

    Al-Aqeel, Aida I

    2009-12-01

    The rapidly changing technologies that involve human subjects raise complex ethical, legal, social, and religious issues. Recent advances in the field of cloning and stem cell research have introduced new hopes for the treatment of serious diseases. But this promise has raised many complex questions. This field causes debate and challenge, not only among scientists but also among ethicists, religious scholars, governments, and politicians. There is no consensus on the morality of human cloning, even within specific religious traditions. In countries in which religion has a strong influence on political decision making, the moral status of the human embryo is at the center of the debate. Because of the inevitable consequences of reproductive cloning, it is prohibited in Islam. However, stem cell research for therapeutic purposes is permissible with full consideration, and all possible precautions in the pre-ensoulment stages of early fetus development, if the source is legitimate.

  10. Biobanking human embryonic stem cell lines: policy, ethics and efficiency.

    Science.gov (United States)

    Holm, Søren

    2015-12-01

    Stem cell banks curating and distributing human embryonic stem cells have been established in a number of countries and by a number of private institutions. This paper identifies and critically discusses a number of arguments that are used to justify the importance of such banks in policy discussions relating to their establishment or maintenance. It is argued (1) that 'ethical arguments' are often more important in the establishment phase and 'efficiency arguments' more important in the maintenance phase, and (2) that arguments relating to the interests of embryo and gamete donors are curiously absent from the particular stem cell banking policy discourse. This to some extent artificially isolates this discourse from the broader discussions about the flows of reproductive materials and tissues in modern society, and such isolation may lead to the interests of important actors being ignored in the policy making process.

  11. Co-Culture of Early Embryo with Human Decidual Stromal Cells in vitro by Improvement of Early Embryo Development

    Institute of Scientific and Technical Information of China (English)

    YAN Jie; ZHU Guijin; LIU Jianxin; AI Jihui

    2000-01-01

    An early embryo co-culture system with human decidual stromal cells was established to study its effect on early embryonic cleavage and growth in vitro. Three hundred and eight 2-cell mouse embryos were co-cultured with human decidual stromal cell monolayer in MEM+0.4%bovine serum albumin (BSA) and 163 embryos cultured in MEM+15 % FCS alone as control. Among the mouse 2-cell embryos co-cultured with human decidual stromal cells, 72.73% developed to the morula stage and 67.21% cavitated to blastocysts with 59.74 % hatching, as compared with 61.34% to morula stage, 48.47% to blastocysts and none hatching in the controls,respectively. Co-cultured embryos cleaved slightly faster than controls and showed no or less fragmentation than those in the control. These results suggested that human decidual stromal cells can support early embryonic development and yield a reasonable number of embryos with good quality up to blastocyst stage.

  12. Isolation and culture of porcine neural progenitor cells from embryos and pluripotent stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Mikkel Aabech; Hall, Vanessa Jane; Hyttel, Poul

    2013-01-01

    therapy. The pig has become recognized as an important large animal model and establishment of in vitro-derived porcine NPCs would allow for preclinical safety testing by transplantation in a porcine biomedical model. In this chapter, a detailed method for isolation and in vitro culture of porcine NPCs...... from porcine embryos or induced pluripotent stem cells is presented. The neural induction is performed in coculture and the isolation of rosette structures is carried out manually to ensure a homogenous population of NPCs. Using this method, multipotent NPCs can be obtained in approximately 1 month...

  13. Functional genomics of 5- to 8-cell stage human embryos by blastomere single-cell cDNA analysis.

    Directory of Open Access Journals (Sweden)

    Amparo Galán

    Full Text Available Blastomere fate and embryonic genome activation (EGA during human embryonic development are unsolved areas of high scientific and clinical interest. Forty-nine blastomeres from 5- to 8-cell human embryos have been investigated following an efficient single-cell cDNA amplification protocol to provide a template for high-density microarray analysis. The previously described markers, characteristic of Inner Cell Mass (ICM (n = 120, stemness (n = 190 and Trophectoderm (TE (n = 45, were analyzed, and a housekeeping pattern of 46 genes was established. All the human blastomeres from the 5- to 8-cell stage embryo displayed a common gene expression pattern corresponding to ICM markers (e.g., DDX3, FOXD3, LEFTY1, MYC, NANOG, POU5F1, stemness (e.g., POU5F1, DNMT3B, GABRB3, SOX2, ZFP42, TERT, and TE markers (e.g., GATA6, EOMES, CDX2, LHCGR. The EGA profile was also investigated between the 5-6- and 8-cell stage embryos, and compared to the blastocyst stage. Known genes (n = 92 such as depleted maternal transcripts (e.g., CCNA1, CCNB1, DPPA2 and embryo-specific activation (e.g., POU5F1, CDH1, DPPA4, as well as novel genes, were confirmed. In summary, the global single-cell cDNA amplification microarray analysis of the 5- to 8-cell stage human embryos reveals that blastomere fate is not committed to ICM or TE. Finally, new EGA features in human embryogenesis are presented.

  14. Functional Genomics of 5- to 8-Cell Stage Human Embryos by Blastomere Single-Cell cDNA Analysis

    Science.gov (United States)

    Galán, Amparo; Montaner, David; Póo, M. Eugenia; Valbuena, Diana; Ruiz, Verónica; Aguilar, Cristóbal; Dopazo, Joaquín; Simón, Carlos

    2010-01-01

    Blastomere fate and embryonic genome activation (EGA) during human embryonic development are unsolved areas of high scientific and clinical interest. Forty-nine blastomeres from 5- to 8-cell human embryos have been investigated following an efficient single-cell cDNA amplification protocol to provide a template for high-density microarray analysis. The previously described markers, characteristic of Inner Cell Mass (ICM) (n = 120), stemness (n = 190) and Trophectoderm (TE) (n = 45), were analyzed, and a housekeeping pattern of 46 genes was established. All the human blastomeres from the 5- to 8-cell stage embryo displayed a common gene expression pattern corresponding to ICM markers (e.g., DDX3, FOXD3, LEFTY1, MYC, NANOG, POU5F1), stemness (e.g., POU5F1, DNMT3B, GABRB3, SOX2, ZFP42, TERT), and TE markers (e.g., GATA6, EOMES, CDX2, LHCGR). The EGA profile was also investigated between the 5-6- and 8-cell stage embryos, and compared to the blastocyst stage. Known genes (n = 92) such as depleted maternal transcripts (e.g., CCNA1, CCNB1, DPPA2) and embryo-specific activation (e.g., POU5F1, CDH1, DPPA4), as well as novel genes, were confirmed. In summary, the global single-cell cDNA amplification microarray analysis of the 5- to 8-cell stage human embryos reveals that blastomere fate is not committed to ICM or TE. Finally, new EGA features in human embryogenesis are presented. PMID:21049019

  15. Generation of human induced pluripotent stem cells from dermal fibroblasts.

    Science.gov (United States)

    Lowry, W E; Richter, L; Yachechko, R; Pyle, A D; Tchieu, J; Sridharan, R; Clark, A T; Plath, K

    2008-02-26

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ectopic expression of the defined transcription factors KLF4, OCT4, SOX2, and C-MYC. The resultant cell lines are morphologically indistinguishable from human embryonic stem cells (HESC) generated from the inner cell mass of a human preimplantation embryo. Consistent with these observations, human iPS cells share a nearly identical gene-expression profile with two established HESC lines. Importantly, DNA fingerprinting indicates that the human iPS cells were derived from the donor material and are not a result of contamination. Karyotypic analyses demonstrate that reprogramming of human cells by defined factors does not induce, or require, chromosomal abnormalities. Finally, we provide evidence that human iPS cells can be induced to differentiate along lineages representative of the three embryonic germ layers indicating the pluripotency of these cells. Our findings are an important step toward manipulating somatic human cells to generate an unlimited supply of patient-specific pluripotent stem cells. In the future, the use of defined factors to change cell fate may be the key to routine nuclear reprogramming of human somatic cells.

  16. Chick embryo xenograft model reveals a novel perineural niche for human adipose-derived stromal cells

    Directory of Open Access Journals (Sweden)

    Ingrid R. Cordeiro

    2015-09-01

    Full Text Available Human adipose-derived stromal cells (hADSC are a heterogeneous cell population that contains adult multipotent stem cells. Although it is well established that hADSC have skeletal potential in vivo in adult organisms, in vitro assays suggest further differentiation capacity, such as into glia. Thus, we propose that grafting hADSC into the embryo can provide them with a much more instructive microenvironment, allowing the human cells to adopt diverse fates or niches. Here, hADSC spheroids were grafted into either the presumptive presomitic mesoderm or the first branchial arch (BA1 regions of chick embryos. Cells were identified without previous manipulations via human-specific Alu probes, which allows efficient long-term tracing of heterogeneous primary cultures. When grafted into the trunk, in contrast to previous studies, hADSC were not found in chondrogenic or osteogenic territories up to E8. Surprisingly, 82.5% of the hADSC were associated with HNK1+ tissues, such as peripheral nerves. Human skin fibroblasts showed a smaller tropism for nerves. In line with other studies, hADSC also adopted perivascular locations. When grafted into the presumptive BA1, 74.6% of the cells were in the outflow tract, the final goal of cardiac neural crest cells, and were also associated with peripheral nerves. This is the first study showing that hADSC could adopt a perineural niche in vivo and were able to recognize cues for neural crest cell migration of the host. Therefore, we propose that xenografts of human cells into chick embryos can reveal novel behaviors of heterogeneous cell populations, such as response to migration cues.

  17. Forecasting science futures: legitimising hope and calming fears in the embryo stem cell debate.

    Science.gov (United States)

    Kitzinger, Jenny; Williams, Clare

    2005-08-01

    Controversies about biotechnologies often centre not so much on present scientific facts as on speculations about risks and benefits in the future. It is this key futuristic element in these arguments that is the focus of this article. We examine how competing visions of utopia or dystopia are defended through the use of diverse vocabularies, metaphors, associations and appeals to authority. Our case study explores how these rhetorical processes play out in the debate about embryo stem cell research in UK national press and TV news media. The findings show how predictions from those in favour of embryo stem cell research are supported by both hype and by anti-hype, by inconsistent appeals to the technologies' innovative status and by the selective deconstruction of concepts such as 'potential' and 'hope'. The debate also mobilises binary oppositions around reason versus emotion, science versus religion and fact versus fiction. This article highlights how traditional assertions of expertise are now combined with ideas about compassion and respect for democracy and diversity. It also highlights the fact that although news reporters are often responding to topical events the real focus is often on years, even decades ahead. Close attention to how images of the future are constructed, and the evolution of new strategies for legitimation are, we suggest, important areas of on-going research, particularly in discussions of scientific and medical developments and policy.

  18. Stem cell differentiation and human liver disease

    Institute of Scientific and Technical Information of China (English)

    Wen-Li Zhou; Claire N Medine; Liang Zhu; David C Hay

    2012-01-01

    Human stem cells are scalable cell populations capable of cellular differentiation.This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells.Such an approach has the potential to improve our understanding of human biology and treating disease.In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases.In recent years,efficient hepatic differentiation from human stem cells has been achieved by several research groups including our own.In this review we provide an overview of the field and discuss the future potential and limitations of stem cell technology.

  19. Pathogenesis, developmental consequences, and clinical correlations of human embryo fragmentation.

    Science.gov (United States)

    Fujimoto, Victor Y; Browne, Richard W; Bloom, Michael S; Sakkas, Denny; Alikani, Mina

    2011-03-15

    This narrative review summarizes the current state of knowledge about human embryo fragmentation during IVF. The clinical relevance of fragmentation is discussed and evidence supporting a central role for the oocyte in the pathogenesis of fragmentation is presented. A mechanism of fragmentation as aberrant cell division involving the cytoskeleton is described along with the novel concept of membrane instability in relation to follicular high-density lipoprotein metabolism and cholesterol transport. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Human stem cells and articular cartilage regeneration.

    Science.gov (United States)

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  1. Human Stem Cells and Articular Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    A. Hari Reddi

    2012-11-01

    Full Text Available  The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  2. Establishment of goat embryonic stem cells from in vivo produced blastocyst-stage embryos.

    Science.gov (United States)

    Behboodi, E; Bondareva, A; Begin, I; Rao, K; Neveu, N; Pierson, J T; Wylie, C; Piero, F D; Huang, Y J; Zeng, W; Tanco, V; Baldassarre, H; Karatzas, C N; Dobrinski, I

    2011-03-01

    Embryonic stem (ES) cells with the capacity for germ line transmission have only been verified in mouse and rat. Methods for derivation, propagation, and differentiation of ES cells from domestic animals have not been fully established. Here, we describe derivation of ES cells from goat embryos. In vivo-derived embryos were cultured on goat fetal fibroblast feeders. Embryos either attached to the feeder layer or remained floating and expanded in culture. Embryos that attached showed a prominent inner cell mass (ICM) and those that remained floating formed structures resembling ICM disks surrounded by trophectodermal cells. ICM cells and embryonic disks were isolated mechanically, cultured on feeder cells in the presence of hLIF, and outgrown into ES-like colonies. Two cell lines were cultured for 25 passages and stained positive for alkaline phosphatase, POU5F1, NANOG, SOX2, SSEA-1, and SSEA-4. Embryoid bodies formed in suspension culture without hLIF. One cell line was cultured for 2 years (over 120 passages). This cell line differentiated in vitro into epithelia and neuronal cells, and could be stably transfected and selected for expression of a fluorescent marker. When cells were injected into SCID mice, teratomas were identified 5-6 weeks after transplantation. Expression of known ES cell markers, maintenance in vitro for 2 years in an undifferentiated state, differentiation in vitro, and formation of teratomas in immunodeficient mice provide evidence that the established cell line represents goat ES cells. This also is the first report of teratoma formation from large animal ES cells.

  3. Generation of induced pluripotent stem cells from human β-thalassemia fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Yixuan Wang; Yonghua Jiang; Sheng Liu; Xiaofang Sun; Shaorong Gao

    2009-01-01

    @@ Dear Editor, Induced pluripotent stem (iPS) cells have recently been generated by directly introducing several transcrip-tion factors into differentiated human somatic cells, and these iPS cells show great similarities to embryo-derived ES cells [1-3].

  4. Embryo splitting

    Directory of Open Access Journals (Sweden)

    Karl Illmensee

    2010-04-01

    Full Text Available Mammalian embryo splitting has successfully been established in farm animals. Embryo splitting is safely and efficiently used for assisted reproduction in several livestock species. In the mouse, efficient embryo splitting as well as single blastomere cloning have been developed in this animal system. In nonhuman primates embryo splitting has resulted in several pregnancies. Human embryo splitting has been reported recently. Microsurgical embryo splitting under Institutional Review Board approval has been carried out to determine its efficiency for blastocyst development. Embryo splitting at the 6–8 cell stage provided a much higher developmental efficiency compared to splitting at the 2–5 cell stage. Embryo splitting may be advantageous for providing additional embryos to be cryopreserved and for patients with low response to hormonal stimulation in assisted reproduction programs. Social and ethical issues concerning embryo splitting are included regarding ethics committee guidelines. Prognostic perspectives are presented for human embryo splitting in reproductive medicine.

  5. Derivation and characterization of novel nonhuman primate embryonic stem cell lines from in vitro-fertilized baboon preimplantation embryos.

    Science.gov (United States)

    Chang, Tien-Cheng; Liu, Ya-Guang; Eddy, Carlton A; Jacoby, Ethan S; Binkley, Peter A; Brzyski, Robert G; Schenken, Robert S

    2011-06-01

    The development of nonhuman primate (NHP) embryonic stem cell (ESC) models holds great promise for cell-mediated treatment of debilitating diseases and to address numerous unanswered questions regarding the therapeutic efficacy of ESCs while supplanting ethical considerations involved with human studies. Here we report successful establishment and characterization of 3 novel baboon (Papio cynocephalus) ESC lines from the inner cell mass of intracytoplasmic sperm injection-derived blastocysts. Embryos were cultured in an improved baboon embryo in vitro culture protocol. The inner cell mass of blastocyst was laser-dissected and plated on mouse embryonic fibroblast feeder cell monolayer in the NHP ESC culture medium. Three cell lines with characteristic ESC morphology have been cultured through an extended period (>14 months), with 2 male cell lines (UT-1 and -2) and 1 female cell line (UT-3) displaying normal baboon karyotypes. Reverse transcription-polymerase chain reaction analysis confirmed that all 3 lines express primate ESC pluripotency markers, including OCT-4, NANOG, SOX-2, TERT, TDGF, LEFTYA, and REX-1. All 3 lines demonstrated positive immunocytochemical staining for OCT-4, stage-specific embryonic antigen-3, stage-specific embryonic antigen-4, TRA-1-60, and TRA-1-81. Baboon ESCs injected into NOD/SCID mice formed teratomas with all 3 germ layers. In addition, embryoid body-like spherical structures were derived and initial outgrowth was observed when embedded into extracellular matrix Matrigel. The ESC lines established in this NHP model have the potential to extend our knowledge in the fields of developmental biology, regenerative medicine, and future applications, including preclinical safety assessment of in vivo stem cell therapy.

  6. Isolation of a pluripotent cell line from early mouse embryos cultured in medium conditioned by teratocarcinoma stem cells.

    Science.gov (United States)

    Martin, G R

    1981-12-01

    This report describes the establishment directly from normal preimplantation mouse embryos of a cell line that forms teratocarcinomas when injected into mice. The pluripotency of these embryonic stem cells was demonstrated conclusively by the observation that subclonal cultures, derived from isolated single cells, can differentiate into a wide variety of cell types. Such embryonic stem cells were isolated from inner cell masses of late blastocysts cultured in medium conditioned by an established teratocarcinoma stem cell line. This suggests that such conditioned medium might contain a growth factor that stimulates the proliferation or inhibits the differentiation of normal pluripotent embryonic cells, or both. This method of obtaining embryonic stem cells makes feasible the isolation of pluripotent cells lines from various types of noninbred embryo, including those carrying mutant genes. The availability of such cell lines should made possible new approaches to the study of early mammalian development.

  7. Cripto is essential to capture mouse epiblast stem cell and human embryonic stem cell pluripotency.

    Science.gov (United States)

    Fiorenzano, Alessandro; Pascale, Emilia; D'Aniello, Cristina; Acampora, Dario; Bassalert, Cecilia; Russo, Francesco; Andolfi, Gennaro; Biffoni, Mauro; Francescangeli, Federica; Zeuner, Ann; Angelini, Claudia; Chazaud, Claire; Patriarca, Eduardo J; Fico, Annalisa; Minchiotti, Gabriella

    2016-09-02

    Known molecular determinants of developmental plasticity are mainly transcription factors, while the extrinsic regulation of this process has been largely unexplored. Here we identify Cripto as one of the earliest epiblast markers and a key extracellular determinant of the naive and primed pluripotent states. We demonstrate that Cripto sustains mouse embryonic stem cell (ESC) self-renewal by modulating Wnt/β-catenin, whereas it maintains mouse epiblast stem cell (EpiSC) and human ESC pluripotency through Nodal/Smad2. Moreover, we provide unprecedented evidence that Cripto controls the metabolic reprogramming in ESCs to EpiSC transition. Remarkably, Cripto deficiency attenuates ESC lineage restriction in vitro and in vivo, and permits ESC transdifferentiation into trophectoderm lineage, suggesting that Cripto has earlier functions than previously recognized. All together, our studies provide novel insights into the current model of mammalian pluripotency and contribute to the understanding of the extrinsic regulation of the first cell lineage decision in the embryo.

  8. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human embryo

  9. iPS cells-alternative pluripotent cells to embryo stem cells

    Institute of Scientific and Technical Information of China (English)

    PEI XueTao

    2010-01-01

    @@ Since the first murine and human embryonic stem cell lines were established by Drs.Evans and Kaufman [1] and Thomson et al.[2], respectively, great progress has been make in the field of stem cell research and regenerative medicine that gave promising futures for therapeutic interventions.However, ethical problems and complications from immune rejection have hindered the full development of ES cells into clinical practice for disease treatment.

  10. The potency of human testicular stem cells

    NARCIS (Netherlands)

    Chikhovskaya, J.V.

    2013-01-01

    In this thesis, we evaluate the stem cell state of cells present in primary human testicular cell cultures as well as their origin and relation to germ or somatic lineages within testicular tissue. We conclude that human testis-derived embryonic stem cell-like (htES-like) colonies arising in primary

  11. Normal human pluripotent stem cell lines exhibit pervasive mosaic aneuploidy.

    Directory of Open Access Journals (Sweden)

    Suzanne E Peterson

    Full Text Available Human pluripotent stem cell (hPSC lines have been considered to be homogeneously euploid. Here we report that normal hPSC--including induced pluripotent--lines are karyotypic mosaics of euploid cells intermixed with many cells showing non-clonal aneuploidies as identified by chromosome counting, spectral karyotyping (SKY and fluorescent in situ hybridization (FISH of interphase/non-mitotic cells. This mosaic aneuploidy resembles that observed in progenitor cells of the developing brain and preimplantation embryos, suggesting that it is a normal, rather than pathological, feature of stem cell lines. The karyotypic heterogeneity generated by mosaic aneuploidy may contribute to the reported functional and phenotypic heterogeneity of hPSCs lines, as well as their therapeutic efficacy and safety following transplantation.

  12. Cryopreservation of human embryos and its contribution to in vitro fertilization success rates.

    Science.gov (United States)

    Wong, Kai Mee; Mastenbroek, Sebastiaan; Repping, Sjoerd

    2014-07-01

    Cryopreservation of human embryos is now a routine procedure in assisted reproductive technologies laboratories. There is no consensus on the superiority of any protocol, and substantial differences exist among centers in day of embryo cryopreservation, freezing method, selection criteria for which embryos to freeze, method of embryo thawing, and endometrial preparation for transfer of frozen-thawed embryos. In the past decade, the number of frozen-thawed embryo transfer cycles per started in vitro fertilization (IVF) cycle increased steadily, and at the same time the percentage of frozen-thawed embryo transfers that resulted in live births increased. Currently, cryopreservation of human embryos is more important than ever for the cumulative pregnancy rate after IVF. Interestingly, success rates after frozen-thawed embryo transfer are now nearing the success rates of fresh embryo transfer. This supports the hypothesis of so called freeze-all strategies in IVF, in which all embryos are frozen and no fresh transfer is conducted, to optimize success rates. High-quality randomized controlled trials should be pursued to find out which cryopreservation protocol is best and whether the time has come to completely abandon fresh transfers.

  13. Pluripotency of embryo-derived stem cells from rodents, lagomorphs, and primates: Slippery slope, terrace and cliff.

    Science.gov (United States)

    Savatier, Pierre; Osteil, Pierre; Tam, Patrick P L

    2017-03-01

    The diverse cell states and in vitro conditions for the derivation and maintenance of the mammalian embryo-derived pluripotent stem cells raise the questions of whether there are multiple states of pluripotency of the stem cells of each species, and if there are innate species-specific variations in the pluripotency state. We will address these questions by taking a snapshot of our knowledge of the properties of the pluripotent stem cells, focusing on the maintenance of pluripotency and inter-conversion of the different types of pluripotent stem cells from rodents, lagomorphs and primates. We conceptualize pluripotent stem cells acquiring a series of cellular states represented as terraces on a slope of descending gradient of pluripotency. We propose that reprogramming pluripotent stem cells from a primed to a naive state is akin to moving upstream over a steep cliff to a higher terrace. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Development of the ventral body wall in the human embryo.

    Science.gov (United States)

    Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Köhler, S Eleonore; Lamers, Wouter H

    2015-11-01

    Migratory failure of somitic cells is the commonest explanation for ventral body wall defects. However, the embryo increases ~ 25-fold in volume in the period that the ventral body wall forms, so that differential growth may, instead, account for the observed changes in topography. Human embryos between 4 and 10 weeks of development were studied, using amira reconstruction and cinema 4D remodeling software for visualization. Initially, vertebrae and ribs had formed medially, and primordia of sternum and hypaxial flank muscle primordium laterally in the body wall at Carnegie Stage (CS)15 (5.5 weeks). The next week, ribs and muscle primordium expanded in ventrolateral direction only. At CS18 (6.5 weeks), separate intercostal and abdominal wall muscles differentiated, and ribs, sterna, and muscles began to expand ventromedially and caudally, with the bilateral sternal bars fusing in the midline after CS20 (7 weeks) and the rectus muscles reaching the umbilicus at CS23 (8 weeks). The near-constant absolute distance between both rectus muscles and approximately fivefold decline of this distance relative to body circumference between 6 and 10 weeks identified dorsoventral growth in the dorsal body wall as determinant of the 'closure' of the ventral body wall. Concomitant with the straightening of the embryonic body axis after the 6th week, the abdominal muscles expanded ventrally and caudally to form the infraumbilical body wall. Our data, therefore, show that the ventral body wall is formed by differential dorsoventral growth in the dorsal part of the body.

  15. Human stem cells from single blastomeres reveal pathways of embryonic or trophoblast fate specification.

    Science.gov (United States)

    Zdravkovic, Tamara; Nazor, Kristopher L; Larocque, Nicholas; Gormley, Matthew; Donne, Matthew; Hunkapillar, Nathan; Giritharan, Gnanaratnam; Bernstein, Harold S; Wei, Grace; Hebrok, Matthias; Zeng, Xianmin; Genbacev, Olga; Mattis, Aras; McMaster, Michael T; Krtolica, Ana; Valbuena, Diana; Simón, Carlos; Laurent, Louise C; Loring, Jeanne F; Fisher, Susan J

    2015-12-01

    Mechanisms of initial cell fate decisions differ among species. To gain insights into lineage allocation in humans, we derived ten human embryonic stem cell lines (designated UCSFB1-10) from single blastomeres of four 8-cell embryos and one 12-cell embryo from a single couple. Compared with numerous conventional lines from blastocysts, they had unique gene expression and DNA methylation patterns that were, in part, indicative of trophoblast competence. At a transcriptional level, UCSFB lines from different embryos were often more closely related than those from the same embryo. As predicted by the transcriptomic data, immunolocalization of EOMES, T brachyury, GDF15 and active β-catenin revealed differential expression among blastomeres of 8- to 10-cell human embryos. The UCSFB lines formed derivatives of the three germ layers and CDX2-positive progeny, from which we derived the first human trophoblast stem cell line. Our data suggest heterogeneity among early-stage blastomeres and that the UCSFB lines have unique properties, indicative of a more immature state than conventional lines.

  16. Simple and efficient production of mice derived from embryonic stem cells aggregated with tetraploid embryos.

    Science.gov (United States)

    Li, Xiangyun; Yu, Yuansong; Wei, Wei; Yong, Jun; Yang, Jie; You, Jiefang; Xiong, Xiaoran; Qing, Tingting; Deng, Hongkui

    2005-06-01

    Six newly derived hybrid mouse embryonic stem (ES) cell lines and two inbred ES cell lines were tested for their ability to produce completely ES cell-derived mice by aggregation of ES cells with tetraploid embryos. Forty-five ES cell-tetraploid pups were generated from six hybrid ES cell lines and no pups from two inbred ES cell lines. These pups were found to have increased embryonic and placental weights than control mice. Twenty-two pups survived to adulthood and produced normal offsprings, and the other 23 pups died of several reasons including respiratory distress, abdomen ulcer-like symptoms, and foster failure. The 22 adult ES cell-tetraploid mice were completely ES cell-derived as judged by coat color and germline transmission, only two of them was found to have tetraploid component in liver, blood, and lung as analyzed by microsatellite loci. Our data suggested that genetic heterozygosity is a crucial factor for postnatal survival of ES cell-tetraploid mice, and tetraploid embryo aggregation using hybrid ES cells is a simple and efficient procedure for immediate generation of targeted mouse mutants from genetically modified ES cell clones, in contrast to the standard protocol, which involves the production of chimeras and several breeding steps.

  17. Essential Role of Chromatin Remodeling Protein Bptf in Early Mouse Embryos and Embryonic Stem Cells

    Science.gov (United States)

    Landry, Joseph; Sharov, Alexei A.; Piao, Yulan; Sharova, Lioudmila V.; Xiao, Hua; Southon, Eileen; Matta, Jennifer; Tessarollo, Lino; Zhang, Ying E.; Ko, Minoru S. H.; Kuehn, Michael R.; Yamaguchi, Terry P.; Wu, Carl

    2008-01-01

    We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor), the largest subunit of NURF (Nucleosome Remodeling Factor) in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf−/− embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf−/− embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo. PMID:18974875

  18. Essential role of chromatin remodeling protein Bptf in early mouse embryos and embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Joseph Landry

    2008-10-01

    Full Text Available We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor, the largest subunit of NURF (Nucleosome Remodeling Factor in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf(-/- embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf(-/- embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo.

  19. A role for Aurora C in the chromosomal passenger complex during human preimplantation embryo development

    NARCIS (Netherlands)

    Santos, Margarida Avo; van de Werken, Christine; de Vries, Marieke; Jahr, Holger; Vromans, Martijn J. M.; Laven, Joop S. E.; Fauser, Bart C.; Kops, Geert J.; Lens, Susanne M.; Baart, Esther B.

    2011-01-01

    BACKGROUND: Human embryos generated by IVF demonstrate a high incidence of chromosomal segregation errors during the cleavage divisions. To analyse underlying molecular mechanisms, we investigated the behaviour of the chromosomal passenger complex (CPC) in human oocytes and embryos. This important m

  20. Parliamentary cultures and human embryos: the Dutch and British debates compared

    NARCIS (Netherlands)

    Kirejczyk, Marta

    1999-01-01

    Twenty years ago, the technology of in vitro fertilization created a new artefact: the human embryo outside the woman's body. In many countries, political debates developed around this artefact. One of the central questions in these debates is whether it is permissible to use human embryos in resear

  1. Potential antitumor therapeutic strategies of human amniotic membrane and amniotic fluid-derived stem cells.

    Science.gov (United States)

    Kang, N-H; Hwang, K-A; Kim, S U; Kim, Y-B; Hyun, S-H; Jeung, E-B; Choi, K-C

    2012-08-01

    As stem cells are capable of self-renewal and can generate differentiated progenies for organ development, they are considered as potential source for regenerative medicine and tissue replacement after injury or disease. Along with this capacity, stem cells have the therapeutic potential for treating human diseases including cancers. According to the origins, stem cells are broadly classified into two types: embryonic stem cells (ESCs) and adult stem cells. In terms of differentiation potential, ESCs are pluripotent and adult stem cells are multipotent. Amnion, which is a membranous sac that contains the fetus and amniotic fluid and functions in protecting the developing embryo during gestation, is another stem cell source. Amnion-derived stem cells are classified as human amniotic membrane-derived epithelial stem cells, human amniotic membrane-derived mesenchymal stem cells and human amniotic fluid-derived stem cells. They are in an intermediate stage between pluripotent ESCs and lineage-restricted adult stem cells, non-tumorigenic, and contribute to low immunogenicity and anti-inflammation. Furthermore, they are easily available and do not cause any controversial issues in their recovery and applications. Not only are amnion-derived stem cells applicable in regenerative medicine, they have anticancer capacity. In non-engineered stem cells transplantation strategies, amnion-derived stem cells effectively target the tumor and suppressed the tumor growth by expressing cytotoxic cytokines. Additionally, they also have a potential as novel delivery vehicles transferring therapeutic genes to the cancer formation sites in gene-directed enzyme/prodrug combination therapy. Owing to their own advantageous properties, amnion-derived stem cells are emerging as a new candidate in anticancer therapy.

  2. Derivation of the human embryonic stem cell line RCe012-A (RC-8

    Directory of Open Access Journals (Sweden)

    P.A. De Sousa

    2016-03-01

    Full Text Available The human embryonic stem cell line RCe012-A (RC-8 was derived from a frozen and thawed day 5 embryo cultivated to the blastocyst stage. The embryo was voluntarily donated as unsuitable and surplus to fertility requirements following ethics committee approved informed consent under licence from the UK Human Fertilisation and Embryology Authority. The cell line shows normal pluripotency marker expression and differentiation to the three germ layers in vitro. It has a normal 46XX female karyotype and microsatellite PCR identity, HLA and blood group typing data is available.

  3. Endocardial tip cells in the human embryo - facts and hypotheses.

    Directory of Open Access Journals (Sweden)

    Mugurel C Rusu

    Full Text Available Experimental studies regarding coronary embryogenesis suggest that the endocardium is a source of endothelial cells for the myocardial networks. As this was not previously documented in human embryos, we aimed to study whether or not endothelial tip cells could be correlated with endocardial-dependent mechanisms of sprouting angiogenesis. Six human embryos (43-56 days were obtained and processed in accordance with ethical regulations; immunohistochemistry was performed for CD105 (endoglin, CD31, CD34, α-smooth muscle actin, desmin and vimentin antibodies. Primitive main vessels were found deriving from both the sinus venosus and aorta, and were sought to be the primordia of the venous and arterial ends of cardiac microcirculation. Subepicardial vessels were found branching into the outer ventricular myocardium, with a pattern of recruiting α-SMA+/desmin+ vascular smooth muscle cells and pericytes. Endothelial sprouts were guided by CD31+/CD34+/CD105+/vimentin+ endothelial tip cells. Within the inner myocardium, we found endothelial networks rooted from endocardium, guided by filopodia-projecting CD31+/CD34+/CD105+/ vimentin+ endocardial tip cells. The myocardial microcirculatory bed in the atria was mostly originated from endocardium, as well. Nevertheless, endocardial tip cells were also found in cardiac cushions, but they were not related to cushion endothelial networks. A general anatomical pattern of cardiac microvascular embryogenesis was thus hypothesized; the arterial and venous ends being linked, respectively, to the aorta and sinus venosus. Further elongation of the vessels may be related to the epicardium and subepicardial stroma and the intramyocardial network, depending on either endothelial and endocardial filopodia-guided tip cells in ventricles, or mostly on endocardium, in atria.

  4. Cortical network from human embryonic stem cells

    OpenAIRE

    2010-01-01

    Abstract The connection of embryonic stem cell technology and developmental biology provides valuable tools to decipher the mechanisms underlying human brain development and diseases, especially among neuronal populations, that are not readily available in primary cultures. It is obviously the case of neurons forming the human cerebral cortex. In the images that are presented, the neurons were generated in vitro from human embryonic stem cells via forebrain-like progenitors. Maintained in cul...

  5. Experimental cloning of embryos through human-rabbit inter-species nuclear transfer

    Institute of Scientific and Technical Information of China (English)

    JI Jingjuan; GUO Tonghang; TONG Xianhong; LUO Lihua; ZHOU Guixiang; FU Yingyun; LIU Yusheng

    2007-01-01

    Therapeutic cloning,which is based on human somatic cell nuclear transfer,is one of our major research objectives.Though inter-species nuclear transfer has been introduced to construct human somatic cell cloned embryos,the effects of type,passage,and preparation method of donor cells on embryo development remain unclear.In our experiment,cloned embryos were reconstructed with different passage and preparation methods of ossocartilaginous cell,skin fibroblast,and cumulus cells.The cumulus cell embryos showed significantly higher development rates than the other two (P<0.05).The development rate of embryos reconstructed with skin fibroblasts of different passage number and somatic cells of different chilling durations showed no significant difference.Also,fluorescence in situ hybridization (FISH)was conducted to detect nuclear derivation of the embryos.The result showed that the nuclei of the inter-species cloned embryo cells came from human.We conclude that (1)cloned embryos can be constructed through human-rabbit interspecies nuclear transfer;(2)different kinds of somatic cells result in different efficiency of nuclear transfer,while in vitro passage of the donor does not influence embryo development;(3)refrigeration is a convenient and efficient donor cell preparation method.Finally,it is feasible to detect DNA gcnotype through FISH.

  6. Analysis of compaction initiation in human embryos by using time-lapse cinematography.

    Science.gov (United States)

    Iwata, Kyoko; Yumoto, Keitaro; Sugishima, Minako; Mizoguchi, Chizuru; Kai, Yoshiteru; Iba, Yumiko; Mio, Yasuyuki

    2014-04-01

    To analyze the initiation of compaction in human embryos in vitro by using time-lapse cinematography (TLC), with the goal of determining the precise timing of compaction and clarifying the morphological changes underlying the compaction process. One hundred and fifteen embryos donated by couples with no further need for embryo-transfer were used in this study. Donated embryos were thawed and processed, and then their morphological behavior during the initiation of compaction was dynamically observed via time-lapse cinematography (TLC) for 5 days. Although the initiation of compaction occurred throughout the period from the 4-cell to 16-cell stage, 99 (86.1 %) embryos initiated compaction at the 8-cell stage or later, with initiation at the 8-cell stage being most frequent (22.6 %). Of these 99 embryos, 49.5 % developed into good-quality blastocysts. In contrast, of the 16 (13.9 %) embryos that initiated compaction prior to the 8-cell stage, only 18.8 % developed into good-quality blastocysts. Embryos that initiated compaction before the 8-cell stage showed significantly higher numbers of multinucleated blastomeres, due to asynchronism in nuclear division at the third mitotic division resulting from cytokinetic failure. The initiation of compaction primarily occurs at the third mitotic division or later in human embryos. Embryos that initiate compaction before the 8-cell stage are usually associated with aberrant embryonic development (i.e., cytokinetic failure accompanied by karyokinesis).

  7. Human embryonic stem cell derivation and directed differentiation.

    Science.gov (United States)

    Trounson, A

    2005-01-01

    Human embryonic stem cells (hESCs) are produced from normal, chromosomally aneuploid and mutant human embryos, which are available from in vitro fertilisation (IVF) for infertility or preimplantation diagnosis. These hESC lines are an important resource for functional genomics, drug screening and eventually cell and gene therapy. The methods for deriving hESCs are well established and repeatable, and are relatively successful, with a ratio of 1:10 to 1:2 hESC lines established to embryos used. hESCs can be formed from morula and blastocyst-stage embryos and from isolated inner cell mass cell (ICM) clusters. The hESCs can be formed and maintained on mouse or human somatic cells in serum-free conditions, and for several passages in cell-free cultures. The hESCs can be transfected with DNA constructs. Their gene expression profiles are being described and immunological characteristics determined. They may be grown indefinitely in culture while maintaining their original karyotype but this must be confirmed from time to time. hESCs spontaneously differentiate in the absence of the appropriate cell feeder layer, when overgrown in culture and when isolated from the ESC colony. All three major embryonic lineages are produced in differentiating attachment cultures and in unattached embryoid bodies. Cell progenitors of interest can be identified by markers, expression of reporter genes and characteristic morphology, and the culture thereafter enriched for further culture to more mature cell types. The most advanced directed differentiation pathways have been developed for neural cells and cardiac muscle cells, but many other cell types including haematopoietic progenitors, endothelial cells, lung alveoli, keratinocytes, pigmented retinal epithelium, neural crest cells and motor neurones, hepatic progenitors and cells that have some markers of gut tissue and pancreatic cells have been produced. The prospects for regenerative medicine are significant and there is much

  8. Human cloning and embryo research: the 2003 John J. Conley Lecture on medical ethics.

    Science.gov (United States)

    George, Robert P

    2004-01-01

    The author, a member of the U.S. President's Council on Bioethics, discusses ethical issues raised by human cloning, whether for purposes of bringing babies to birth or for research purposes. He first argues that every cloned human embryo is a new, distinct, and enduring organism, belonging to the species Homo sapiens, and directing its own development toward maturity. He then distinguishes between two types of capacities belonging to individual organisms belonging to this species, an immediately exerciseable capacity and a basic natural capacity that develops over time. He argues that it is the second type of capacity that is the ground for full moral respect, and that this capacity (and its concomitant degree of respect) belongs to cloned human embryos no less than to adult human beings. He then considers and rejects counter-arguments to his position, including the suggestion that the capacity of embryos is equivalent to the capacity of somatic cells, that full human rights are afforded only to human organisms with functioning brains, that the possibility of twinning diminishes the moral status of embryos, that the fact that people do not typically mourn the loss of early embryos implies that they have a diminished moral status, that the fact that early spontaneous abortions occur frequently diminishes the moral status of embryos, and that his arguments depend upon a concept of ensoulment. He concludes that if the moral status of cloned human embryos is equivalent to that of adults, then public policy should be based upon this assumption.

  9. Genome-wide uniparental disomy screen in human discarded morphologically abnormal embryos.

    Science.gov (United States)

    Xu, Jiawei; Zhang, Meixiang; Niu, Wenbin; Yao, Guidong; Sun, Bo; Bao, Xiao; Wang, Linlin; Du, Linqing; Sun, Yingpu

    2015-07-21

    Uniparental disomy (UPD) has been shown to be rare in human normal blastocysts, but its frequency in discarded morphologically abnormal embryos and its relevance to embryonic self-correction of aneuploid remains unknown. The aim of this study was to detect UPD in discarded morphologically abnormal embryos. Both discarded morphologically abnormal embryos, including zero-pronuclear zygotes (0PN), one-pronuclear zygotes (1PN), three-pronuclear zygotes (3PN) and 2PN embryos scored as low development potential were cultured into blastocysts then underwent trophectoderm biopsy. Genome-wide UPD screening of the trophectoderm of 241 discarded morphologically abnormal embryo sourced blastocysts showed that UPD occurred in nine embryos. Five embryos exhibited UPDs with euploid chromosomes, and four displayed UPDs with chromosomal aneuploid. The percentage of UPDs among the morphologically abnormal sourced blastocysts was 3.73%, which is significant higher than the percentage observed in normal blastocysts. The frequency of UPD in 3PN-sourced blastocysts was 7.69%, which is significantly higher than that in normal blastocysts. This study provides the first systematic genome-wide profile of UPD in discarded morphologically abnormal embryos. Our results indicated that UPD may be a common phenomenon in discarded morphologically abnormal embryos and may be relevant to human embryonic self-correction.

  10. 3 CFR - Guidelines for Human Stem Cell Research

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Guidelines for Human Stem Cell Research Presidential Documents Other Presidential Documents Memorandum of July 30, 2009 Guidelines for Human Stem Cell Research..., scientifically worthy human stem cell research, including human embryonic stem cell research, to the extent...

  11. Ethical aspects of human embryonic stem cell research in the islamic world: positions and reflections.

    Science.gov (United States)

    Ilkilic, Ilhan; Ertin, Hakan

    2010-06-01

    Rapid technological developments in human embryonic stem cell research are holding promises of future new medical treatment for a range of currently incurable chronic diseases. At the same time, stem cell research using human embryos raises radically new, previously unimaginable ethical issues posing a dramatic challenge to humankind. By analysing the discourses on these ethical issues we can show that the cultural values and religious convictions of all stakeholders involved play a decisive role in formulating ethical positions. In the Islamic world, too, stem cell research using human embryos provokes new discussions about the moral status of the embryo according to Islamic ethical norms. In our paper we describe the theological and philosophical criteria used in this debate and discuss some ethical positions vis-à-vis embryonic stem cell research formulated in the Islamic world, including official regulations existing in some Muslim countries. While most of the existing literature in this field is primarily descriptive, the present paper endeavours to examine not only the arguments and their historical conditions as such; in addition, we will for the first time provide a critical reflection on the methodology underlying commonly held positions. In our view, this reflection is of paramount importance in establishing a straightforward constructive dialogue between different cultures and academic disciplines.

  12. At the edge of humanity: human stem cells, chimeras, and moral status.

    Science.gov (United States)

    Streiffer, Robert

    2005-12-01

    Experiments involving the transplantation of human stem cells and their derivatives into early fetal or embryonic nonhuman animals raise novel ethical issues due to their possible implications for enhancing the moral status of che chimeric individual. Although status-enhancing research is not necessarily objectionable from the perspective of the chimeric individual, there are grounds for objecting to it in the conditions in which it is likely to occur. Translating this ethical conclusion into a policy recommendation, however, is complicated by the fact that substantial empirical and ethical uncertainties remain about which transplants, if any, would significantly enhance the chimeric individual's moral status. Considerations of moral status justify either an early-termination policy on chimeric embryos, or, in the absence of such a policy, restrictions on the introduction of pluripotent human stem cells into early-stage developing animals, pending the resolution of those uncertainties.

  13. [Triploid cloned human embryos: ethical, social, and legal aspects].

    Science.gov (United States)

    Bellver Capella, Vicente

    2012-01-01

    This work attempts to place the experiment within the scientific and social framework of pluripotent-stem-cell research and offer reflections of an ethical and (to a lesser extent) legal nature on the results obtained by this research group. To these ends, the work is divided into two parts. The first part describes the most important aspects of Noggle and Egli's announcement and the biotechnological and media context in which it was made. The second part is concerned with the bioethical issues raised by the experiment. There are basically four issues, which relate to: (1) the nuclear transfer technique, (2) the use of human ovules to carry out the experiment, (3) the destruction of human blastocysts, and (4) the ethical requirements of scientific publications.

  14. Sox17-Mediated XEN Cell Conversion Identifies Dynamic Networks Controlling Cell-Fate Decisions in Embryo-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Angela C.H. McDonald

    2014-10-01

    Full Text Available Little is known about the gene regulatory networks (GRNs distinguishing extraembryonic endoderm (ExEn stem (XEN cells from those that maintain the extensively characterized embryonic stem cell (ESC. An intriguing network candidate is Sox17, an essential transcription factor for XEN derivation and self-renewal. Here, we show that forced Sox17 expression drives ESCs toward ExEn, generating XEN cells that contribute to ExEn when placed back into early mouse embryos. Transient Sox17 expression is sufficient to drive this fate change during which time cells transit through distinct intermediate states prior to the generation of functional XEN-like cells. To orchestrate this conversion process, Sox17 acts in autoregulatory and feedforward network motifs, regulating dynamic GRNs directing cell fate. Sox17-mediated XEN conversion helps to explain the regulation of cell-fate changes and reveals GRNs regulating lineage decisions in the mouse embryo.

  15. ES cells derived from cloned embryos in monkey - a jump toward human therapeutic cloning

    Institute of Scientific and Technical Information of China (English)

    Xiangzhong Yang; Sadie L Smith

    2007-01-01

    @@ Therapeutic cloning refers to the derivation of embryonic stem cells (ntESC) from embryos derived from somatic cell nuclear transfer (SCNT) also known as cloning. Cloning involves transplanting a differentiated cell into an oocyte that has had its nucleus (DNA) removed.

  16. Heteroparental blastocyst production from microsurgically corrected tripronucleated human embryos.

    Science.gov (United States)

    Escribá, María-José; Martín, Julio; Rubio, Carmen; Valbuena, Diana; Remohí, José; Pellicer, Antonio; Simón, Carlos

    2006-12-01

    To prove the efficiency of identification and removal of one of the surplus paternal pronuclei in dispermic IVF zygotes to obtain heteroparental blastocysts. Experimental. One hundred fourteen tripronucleated (3PN) embryos from conventional IVF. After informed and signed consent, the patients from Instituto Valenciano Infertilidad (IVI), Valencia, donated their abnormally fertilized embryos. Seventy-two embryos were diploidized by microsurgical removal of the pronucleus located at the farthest position to the second polar body. Forty-two 3PN embryos served as controls. Survival and correction rate; in vitro development up to the blastocyst stage; X, Y, and 18 chromosome determination by triple fluorescent in situ hybridization and, inheritance analysis for 10 polymorphic repeat regions using polymerase chain reaction (PCR) amplification and sequencing. Seventy-eight percent of 3PN zygotes (56/72) survived manipulation and eventually 51 zygotes had two pronuclei (71%). Forty-one percent of manipulated embryos progressed in vitro to the blastocyst stage (21/51). Fluorescent in situ hybridization analysis performed on eight manipulated embryos confirmed their diploid state; all four controls were triploid. Heteroparental inheritances were also confirmed in four of six manipulated embryos. Heteroparental blastocysts can be derived from corrected dispermic zygotes.

  17. Defining the nature of human pluripotent stem cell progeny

    Institute of Scientific and Technical Information of China (English)

    Michaela Patterson; David N Chan; Iris Ha; Dana Case; Yongyan Cui; Ben Van Handel; Hanna KA Mikkola; William E Lowry

    2012-01-01

    While it is clear that human pluripotent stem cells (hPSCs) can differentiate to generate a panoply of various cell types,it is unknown how closely in vitro development mirrors that which occurs in vivo.To determine whether human embryonic stem cells (hESCs) and human-induced pluripotent stem cells (hiPSCs) make equivalent progeny,and whether either makes cells that are analogous to tissue-derived cells,we performed comprehensive transcriptome profiling of purified PSC derivatives and their tissue-derived counterparts.Expression profiling demonstrated that hESCs and hiPSCs make nearly identical progeny for the neural,hepatic,and mesenchymal lineages,and an absence of re-expression from exogenous reprogramming factors in hiPSC progeny.However,when compared to a tissuederived counterpart,the progeny of both hESCs and hiPSCs maintained expression of a subset of genes normally associated with early mammalian development,regardless of the type of cell generated.While pluripotent genes (OCT4,SOX2,REX1,and NANOG) appeared to be silenced immediately upon differentiation from hPSCs,genes normally unique to early embryos (LIN28A,LIN28B,DPPA4,and others) were not fully silenced in hPSC derivatives.These data and evidence from expression patterns in early human fetal tissue (3-16 weeks of development) suggest that the differentiated progeny of hPSCs are reflective of very early human development (< 6 weeks).These findings provide support for the idea that hPSCs can serve as useful in vitro models of early human development,but also raise important issues for disease modeling and the clinical application of hPSC derivatives.

  18. Temporal and Developmental-Stage Variation in the Occurrence of Mitotic Errors in Tripronuclear Human Preimplantation Embryos

    NARCIS (Netherlands)

    Mantikou, Eleni; van Echten-Arends, Jannie; Sikkema-Raddatz, Birgit; van der Veen, Fulco; Repping, Sjoerd; Mastenbroek, Sebastiaan

    2013-01-01

    Mitotic errors during early development of human preimplantation embryos are common, rendering a large proportion of embryos chromosomally mosaic. It is also known that the percentage of diploid cells in human diploid-aneuploid mosaic embryos is higher at the blastocyst than at the cleavage stage. I

  19. The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis

    Directory of Open Access Journals (Sweden)

    Danilo Cimadomo

    2016-01-01

    Full Text Available Preimplantation Genetic Diagnosis and Screening (PGD/PGS for monogenic diseases and/or numerical/structural chromosomal abnormalities is a tool for embryo testing aimed at identifying nonaffected and/or euploid embryos in a cohort produced during an IVF cycle. A critical aspect of this technology is the potential detrimental effect that the biopsy itself can have upon the embryo. Different embryo biopsy strategies have been proposed. Cleavage stage blastomere biopsy still represents the most commonly used method in Europe nowadays, although this approach has been shown to have a negative impact on embryo viability and implantation potential. Polar body biopsy has been proposed as an alternative to embryo biopsy especially for aneuploidy testing. However, to date no sufficiently powered study has clarified the impact of this procedure on embryo reproductive competence. Blastocyst stage biopsy represents nowadays the safest approach not to impact embryo implantation potential. For this reason, as well as for the evidences of a higher consistency of the molecular analysis when performed on trophectoderm cells, blastocyst biopsy implementation is gradually increasing worldwide. The aim of this review is to present the evidences published to date on the impact of the biopsy at different stages of preimplantation development upon human embryos reproductive potential.

  20. The biological basis of non-invasive strategies for selection of human oocytes and embryos.

    Science.gov (United States)

    Scott, Lynette

    2003-01-01

    There is a need for more accurate embryo selection in human assisted reproduction, if the goal of reducing the number of embryos used in embryo transfer is to be realized. Furthermore, any selection strategy should be non-invasive if the embryos are to be used in embryo transfer. Currently, the strategy is selection by one to three parameters in the cleaving- and blastocyst-stage embryo, sometimes with additional pronuclear selection. It is clear that no one system is ideal, as the vast majority of transferred embryos do not implant. As the health of the embryo is largely dictated by the originating gametes, the very early events in oocyte development should be considered. This review will point to the early biological events in the unfertilized and fertilized oocyte that can be scored non-invasively and which can have a profound effect on the later developmental stages. Using a sequential scoring system, with emphasis on the oocyte, a system for selecting the most viable single embryo for transfer may hopefully be achieved.

  1. The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis

    Science.gov (United States)

    Cimadomo, Danilo; Capalbo, Antonio; Ubaldi, Filippo Maria; Scarica, Catello; Palagiano, Antonio; Canipari, Rita; Rienzi, Laura

    2016-01-01

    Preimplantation Genetic Diagnosis and Screening (PGD/PGS) for monogenic diseases and/or numerical/structural chromosomal abnormalities is a tool for embryo testing aimed at identifying nonaffected and/or euploid embryos in a cohort produced during an IVF cycle. A critical aspect of this technology is the potential detrimental effect that the biopsy itself can have upon the embryo. Different embryo biopsy strategies have been proposed. Cleavage stage blastomere biopsy still represents the most commonly used method in Europe nowadays, although this approach has been shown to have a negative impact on embryo viability and implantation potential. Polar body biopsy has been proposed as an alternative to embryo biopsy especially for aneuploidy testing. However, to date no sufficiently powered study has clarified the impact of this procedure on embryo reproductive competence. Blastocyst stage biopsy represents nowadays the safest approach not to impact embryo implantation potential. For this reason, as well as for the evidences of a higher consistency of the molecular analysis when performed on trophectoderm cells, blastocyst biopsy implementation is gradually increasing worldwide. The aim of this review is to present the evidences published to date on the impact of the biopsy at different stages of preimplantation development upon human embryos reproductive potential. PMID:26942198

  2. Expression of microRNAs in bovine and human pre-implantation embryo culture media

    Directory of Open Access Journals (Sweden)

    Jenna eKropp

    2014-04-01

    Full Text Available MicroRNAs (miRNA are short non-coding RNAs which act to regulate expression of genes driving numerous cellular processes. These RNAs are secreted within exosomes from cells into the extracellular environment where they may act as signaling molecules. In addition, they are relatively stable and are specifically expressed in association to certain cancers making them strong candidates as biological markers. Moreover, miRNAs have been detected in body fluids including urine, milk, saliva, semen, and blood plasma. However, it is unknown whether they are secreted by embryonic cells into the culture media. Given that miRNAs are expressed throughout embryonic cellular divisions and embryonic genome activation, we hypothesized that they are secreted from the embryo into the extracellular environment and may play a role in the developmental competence of bovine embryos. To test this hypothesis, bovine embryos were cultured individually from day 5 to day 8 of development in an in vitro fertilization system and gene expression of 5 miRNAs was analyzed in both embryos and culture media. Differential miRNA gene expression was observed between embryos that developed to the blastocyst stage and those that failed to develop from the morula to blastocyst stage, deemed degenerate embryos. MiR-25, mir-302c, miR-196a2, and miR-181a expression was found to be higher in degenerate embryos compared to blastocyst embryos. Interestingly, these miRNAs were also found to be expressed in the culture media of both bovine and human pre-implantation embryos. Overall, our results show for the first time that miRNAs are secreted from pre-implantation embryos into culture media and that miRNA expression may correlate with developmental competence of the embryo. Expression of miRNAs in in vitro culture media could allow for the development of biological markers for selection of better quality embryos and for subsequent successful pregnancy.

  3. Human hair genealogies and stem cell latency

    Directory of Open Access Journals (Sweden)

    Tavaré Simon

    2006-02-01

    Full Text Available Abstract Background Stem cells divide to reproduce themselves and produce differentiated progeny. A fundamental problem in human biology has been the inability to measure how often stem cells divide. Although it is impossible to observe every division directly, one method for counting divisions is to count replication errors; the greater the number of divisions, the greater the numbers of errors. Stem cells with more divisions should produce progeny with more replication errors. Methods To test this approach, epigenetic errors (methylation in CpG-rich molecular clocks were measured from human hairs. Hairs exhibit growth and replacement cycles and "new" hairs physically reappear even on "old" heads. Errors may accumulate in long-lived stem cells, or in their differentiated progeny that are eventually shed. Results Average hair errors increased until two years of age, and then were constant despite decades of replacement, consistent with new hairs arising from infrequently dividing bulge stem cells. Errors were significantly more frequent in longer hairs, consistent with long-lived but eventually shed mitotic follicle cells. Conclusion Constant average hair methylation regardless of age contrasts with the age-related methylation observed in human intestine, suggesting that error accumulation and therefore stem cell latency differs among tissues. Epigenetic molecular clocks imply similar mitotic ages for hairs on young and old human heads, consistent with a restart with each new hair, and with genealogies surreptitiously written within somatic cell genomes.

  4. Rationality and religion in the public debate on embryo stem cell research and prenatal diagnostics.

    Science.gov (United States)

    Myskja, Bjørn K

    2009-06-01

    Jürgen Habermas has argued that religious views form a legitimate background for contributions to an open public debate, and that religion plays a particular role in formulating moral intuitions. Translating religious arguments into "generally accessible language" (Habermas, Eur J Philos 14(1):1-25, 2006) to enable them to play a role in political decisions is a common task for religious and non-religious citizens. The article discusses Habermas' view, questioning the particular role of religion, but accepting the significance of including such counter-voices to the predominant views. Furthermore it is pointed out that not only religious but also numerous secular views stand in need of translation to be able to bear on policy matters. Accepting Habermas' general framework, I raise the question whether experts (such as clinicians working in relevant specialised areas of care) participating in political debates on biomedical issues have a duty to state their religious worldview, and to what extent the American government decision to restrict embryo stem cell research is an illegitimate transgression of the State-Church divide.

  5. Persons and their bodies: how we should think about human embryos.

    Science.gov (United States)

    McLachlan, Hugh V

    2002-01-01

    The status of human embryos is discussed particularly in the light of the claim by Fox, in Health Care Analysis 8 that it would be useful to think of them in terms of cyborg metaphors. It is argued that we should consider human embryos for what they are--partially formed human bodies--rather than for what they are like in some respects (and unlike in others)--cyborgs. However to settle the issue of the status of the embryo is not to answer the moral questions which arise concerning how embryos should be treated. Since persons rather than bodies have rights, embryos do not have rights. However, whether or not embryos have rights, people can have duties concerning them. Furthermore, the persons whose fully developed bodies embryos will, might (or might have) become can have rights. Contrary to what is often assumed, it is not merely persons who have (or have had) living, developed human bodies who have moral rights: so it is argued in this paper.

  6. Centre for human development, stem cells & regeneration.

    Science.gov (United States)

    Oreffo, Richard O C

    2014-01-01

    The Centre for Human Development, Stem Cells and Regeneration (CHDSCR) was founded in 2004 as a cross-disciplinary research and translational program within the Faculty of Medicine at the University of Southampton. The Centre undertakes fundamental research into early development and stem cells together with applied translational research for patient benefit. The Centre has vibrant and thriving multidisciplinary research programs that harness the translational strength of the Faculty together with an innovative Stem Cell PhD program, outstanding clinical infrastructure and enterprise to deliver on this vision.

  7. Biobanking human embryonic stem cell lines

    DEFF Research Database (Denmark)

    Holm, Søren

    2016-01-01

    Stem cell banks curating and distributing human embryonic stem cells have been established in a number of countries and by a number of private institutions. This paper identifies and critically discusses a number of arguments that are used to justify the importance of such banks in policy...... are curiously absent from the particular stem cell banking policy discourse. This to some extent artificially isolates this discourse from the broader discussions about the flows of reproductive materials and tissues in modern society, and such isolation may lead to the interests of important actors being...

  8. Self-correction in human embryos%胚胎自我修复

    Institute of Scientific and Technical Information of China (English)

    徐艳文

    2013-01-01

    Reanalysis of aneuploid embryos diagnosed by preimplantation genetic screening (PGS) using fluorescence in situ hybridization(FISH) showed that part or all cells in some human cleavage-stage embryos may undergo self-correction during preimplantation development. Putative embryo self-correction mechanisms include embryonic mosaicism, preferential segregation of chromosomal abnormalities to the trophectoderm and extrusion or duplication of aneuploid chromosomes resulting in uniparental disomy. However, embryo self-correction has not been proved in the study using a single nucleotide polymorphism (SNP)microarray-based 24 chromosome aneuploidy screening technology. Neither preferential segregation of aneuploidy to trophectoderm nor uniparental disomy was found. Further study to improve the accuracy of karyotyping on cleavage-stage embryos is definitely needed.

  9. Derivation of novel human ground state naive pluripotent stem cells.

    Science.gov (United States)

    Gafni, Ohad; Weinberger, Leehee; Mansour, Abed AlFatah; Manor, Yair S; Chomsky, Elad; Ben-Yosef, Dalit; Kalma, Yael; Viukov, Sergey; Maza, Itay; Zviran, Asaf; Rais, Yoach; Shipony, Zohar; Mukamel, Zohar; Krupalnik, Vladislav; Zerbib, Mirie; Geula, Shay; Caspi, Inbal; Schneir, Dan; Shwartz, Tamar; Gilad, Shlomit; Amann-Zalcenstein, Daniela; Benjamin, Sima; Amit, Ido; Tanay, Amos; Massarwa, Rada; Novershtern, Noa; Hanna, Jacob H

    2013-12-12

    Mouse embryonic stem (ES) cells are isolated from the inner cell mass of blastocysts, and can be preserved in vitro in a naive inner-cell-mass-like configuration by providing exogenous stimulation with leukaemia inhibitory factor (LIF) and small molecule inhibition of ERK1/ERK2 and GSK3β signalling (termed 2i/LIF conditions). Hallmarks of naive pluripotency include driving Oct4 (also known as Pou5f1) transcription by its distal enhancer, retaining a pre-inactivation X chromosome state, and global reduction in DNA methylation and in H3K27me3 repressive chromatin mark deposition on developmental regulatory gene promoters. Upon withdrawal of 2i/LIF, naive mouse ES cells can drift towards a primed pluripotent state resembling that of the post-implantation epiblast. Although human ES cells share several molecular features with naive mouse ES cells, they also share a variety of epigenetic properties with primed murine epiblast stem cells (EpiSCs). These include predominant use of the proximal enhancer element to maintain OCT4 expression, pronounced tendency for X chromosome inactivation in most female human ES cells, increase in DNA methylation and prominent deposition of H3K27me3 and bivalent domain acquisition on lineage regulatory genes. The feasibility of establishing human ground state naive pluripotency in vitro with equivalent molecular and functional features to those characterized in mouse ES cells remains to be defined. Here we establish defined conditions that facilitate the derivation of genetically unmodified human naive pluripotent stem cells from already established primed human ES cells, from somatic cells through induced pluripotent stem (iPS) cell reprogramming or directly from blastocysts. The novel naive pluripotent cells validated herein retain molecular characteristics and functional properties that are highly similar to mouse naive ES cells, and distinct from conventional primed human pluripotent cells. This includes competence in the generation

  10. Identification of CD146 Expression in Human and Mouse Preimplantation Embryo

    Institute of Scientific and Technical Information of China (English)

    Hong-bo WANG; Xuan DU; Ya-hui XU; Ze-hua WANG

    2008-01-01

    Objective To investigate whether CD146, a cell adhesion molecule, is expressed in mouse and human preimplantation blastocysts and to localize CD146 in the layer of trophectoderm(TE) and/or inner cell mass(ICM). Methods Human and mouse embryos were collected. Using reverse transcription polymerase chain reaction(RT-PCR), the expression of CD146 mRNA in blastocyst was evaluated in human and mouse embryos. Single embryo immunohistochemical staining was applicated in the examination of the expression of CD146 in protein level. The statistical significance of the data was analyzed using t-test. Results CD146 transcript was detected in all human and mouse preimplantation morula and blastocyst. The expression of CD146 was found to localize in human and mouse compacted morula stage embryos and the TE and ICM of the expanded blastocysts. Conclusion mRNA and protein of CD146 was expressed in preimplantation embryos,which may have a profound influence on early preimplantation development for the differentiation of the trophectoderm and the morphogenesis of the blastocyst.Furthermore, the expression of CD146 in blastocyst stage may be implicated in the assistance of embryo implantation.

  11. Natural selection of human embryos: impaired decidualization of endometrium disables embryo-maternal interactions and causes recurrent pregnancy loss.

    Directory of Open Access Journals (Sweden)

    Madhuri Salker

    Full Text Available BACKGROUND: Recurrent pregnancy loss (RPL, defined as 3 or more consecutive miscarriages, is widely attributed either to repeated chromosomal instability in the conceptus or to uterine factors that are poorly defined. We tested the hypothesis that abnormal cyclic differentiation of endometrial stromal cells (ESCs into specialized decidual cells predisposes to RPL, based on the observation that this process may not only be indispensable for placenta formation in pregnancy but also for embryo recognition and selection at time of implantation. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of mid-secretory endometrial biopsies demonstrated that RPL is associated with decreased expression of the decidual marker prolactin (PRL but increased levels of prokineticin-1 (PROK1, a cytokine that promotes implantation. These in vivo findings were entirely recapitulated when ESCs were purified from patients with and without a history of RPL and decidualized in culture. In addition to attenuated PRL production and prolonged and enhanced PROK1 expression, RPL was further associated with a complete dysregulation of both markers upon treatment of ESC cultures with human chorionic gonadotropin, a glycoprotein hormone abundantly expressed by the implanting embryo. We postulated that impaired embryo recognition and selection would clinically be associated with increased fecundity, defined by short time-to-pregnancy (TTP intervals. Woman-based analysis of the mean and mode TTP in a cohort of 560 RPL patients showed that 40% can be considered "superfertile", defined by a mean TTP of 3 months or less. CONCLUSIONS: Impaired cyclic decidualization of the endometrium facilitates implantation yet predisposes to subsequent pregnancy failure by disabling natural embryo selection and by disrupting the maternal responses to embryonic signals. These findings suggest a novel pathological pathway that unifies maternal and embryonic causes of RPL.

  12. Characterization of human pluripotent stem cells.

    Science.gov (United States)

    Gokhale, Paul J; Andrews, Peter W

    2013-12-18

    Human pluripotent stem cells (PSCs), whether embryonic stem cells or induced PSCs, offer enormous opportunities for regenerative medicine and other biomedical applications once we have developed the ability to harness their capacity for extensive differentiation. Central to this is our ability to identify and characterize such PSCs, but this is fraught with potential difficulties that arise from a tension between functional definitions of pluripotency and the more convenient use of 'markers', a problem exacerbated by ethical issues, our lack of knowledge of early human embryonic development, and differences from the mouse paradigm.

  13. Somatic cell nuclear transfer-derived embryonic stem cell lines in humans: pros and cons.

    Science.gov (United States)

    Langerova, Alena; Fulka, Helena; Fulka, Josef

    2013-12-01

    The recent paper, published by Mitalipov's group in Cell (Tachibana et al., 2013 ), reporting the production of human somatic cell nuclear transfer (SCNT) embryonic stem cells (ESCs), opens again the debate if, in the era of induced pluripotent stem cells (iPSCs), the production of these cells is indeed necessary and, if so, whether they are different from ESCs produced from spare embryos and iPSCs. It is our opinion that these questions are very difficult to answer because it is still unclear whether and how normal ESCs differ from iPSCs.

  14. Characterization and multilineage differentiation of embryonic stem cells derived from a buffalo parthenogenetic embryo.

    Science.gov (United States)

    Sritanaudomchai, Hathaitip; Pavasuthipaisit, Kanok; Kitiyanant, Yindee; Kupradinun, Piengchai; Mitalipov, Shoukhrat; Kusamran, Thanit

    2007-10-01

    Embryonic stem (ES) cells derived from mammalian embryos have the ability to form any terminally differentiated cell of the body. We herein describe production of parthenogenetic buffalo (Bubalus Bubalis) blastocysts and subsequent isolation of an ES cell line. Established parthenogenetic ES (PGES) cells exhibited diploid karyotype and high telomerase activity. PGES cells showed remarkable long-term proliferative capacity providing the possibility for unlimited expansion in culture. Furthermore, these cells expressed key ES cell-specific markers defined for primate species including stage-specific embryonic antigen-4 (SSEA-4), tumor rejection antigen-1-81 (TRA-1-81), and octamer-binding transcription factor 4 (Oct-4). In vitro, in the absence of a feeder layer, cells readily formed embryoid bodies (EBs). When cultured for an extended period of time, EBs spontaneously differentiated into derivatives of three embryonic germ layers as detected by PCR for ectodermal (nestin, oligodendrocytes, and tubulin), mesodermal (scleraxis, alpha-skeletal actin, collagen II, and osteocalcin) and endodermal markers (insulin and alpha-fetoprotein). Differentiation of PGES cells toward chondrocyte lineage was directed by supplementing serum-containing media with ascorbic acid, beta-glycerophosphate, and dexamethasone. Moreover, when PGES cells were injected into nude mice, teratomas with derivatives representing all three embryonic germ layers were produced. Our results suggest that the cell line isolated from a parthenogenetic blastocyst holds properties of ES cells, and can be used as an in vitro model to study the effects of imprinting on cell differentiation and as an a invaluable material for extensive molecular studies on imprinted genes.

  15. My Corporis Fabrica Embryo: An ontology-based 3D spatio-temporal modeling of human embryo development.

    Science.gov (United States)

    Rabattu, Pierre-Yves; Massé, Benoit; Ulliana, Federico; Rousset, Marie-Christine; Rohmer, Damien; Léon, Jean-Claude; Palombi, Olivier

    2015-01-01

    Embryology is a complex morphologic discipline involving a set of entangled mechanisms, sometime difficult to understand and to visualize. Recent computer based techniques ranging from geometrical to physically based modeling are used to assist the visualization and the simulation of virtual humans for numerous domains such as surgical simulation and learning. On the other side, the ontology-based approach applied to knowledge representation is more and more successfully adopted in the life-science domains to formalize biological entities and phenomena, thanks to a declarative approach for expressing and reasoning over symbolic information. 3D models and ontologies are two complementary ways to describe biological entities that remain largely separated. Indeed, while many ontologies providing a unified formalization of anatomy and embryology exist, they remain only descriptive and make the access to anatomical content of complex 3D embryology models and simulations difficult. In this work, we present a novel ontology describing the development of the human embryology deforming 3D models. Beyond describing how organs and structures are composed, our ontology integrates a procedural description of their 3D representations, temporal deformation and relations with respect to their developments. We also created inferences rules to express complex connections between entities. It results in a unified description of both the knowledge of the organs deformation and their 3D representations enabling to visualize dynamically the embryo deformation during the Carnegie stages. Through a simplified ontology, containing representative entities which are linked to spatial position and temporal process information, we illustrate the added-value of such a declarative approach for interactive simulation and visualization of 3D embryos. Combining ontologies and 3D models enables a declarative description of different embryological models that capture the complexity of human

  16. [Humans or material? Three levels of the discourse about the stem cell research from theological-ethical view].

    Science.gov (United States)

    Ernst, Stephan

    2004-01-01

    In the debate on the ethical evaluation of the stem cell research three levels can be differentiated. The first level of argumentation is that of weighing up goods: The possible therapeutical success for thousands of humans seems to justify the consumption of a few embryos. It is show, that this, however, already presupposes - on a second argumentation level - a judgement on the moral status of the embryo. Different moments of time, when human dignity and life protection are ascribe to the embryo, have already been discussed, but in spite of all rationality of the arguments a consensus has not been reached. On this third level of argumentation two fundamental meanings of reality can be differentiated. The empirical-observing and the communicative-participating view. These lead to a different moral evaluation of the embryo. This contribution votes for the priority of the communicative-participating view. It receives addition support by theology and Christian faith.

  17. Human embryonic stem cells as models for aneuploid chromosomal syndromes.

    Science.gov (United States)

    Biancotti, Juan-Carlos; Narwani, Kavita; Buehler, Nicole; Mandefro, Berhan; Golan-Lev, Tamar; Yanuka, Ofra; Clark, Amander; Hill, David; Benvenisty, Nissim; Lavon, Neta

    2010-09-01

    Syndromes caused by chromosomal aneuploidies are widely recognized genetic disorders in humans and often lead to spontaneous miscarriage. Preimplantation genetic screening is used to detect chromosomal aneuploidies in early embryos. Our aim was to derive aneuploid human embryonic stem cell (hESC) lines that may serve as models for human syndromes caused by aneuploidies. We have established 25 hESC lines from blastocysts diagnosed as aneuploid on day 3 of their in vitro development. The hESC lines exhibited morphology and expressed markers typical of hESCs. They demonstrated long-term proliferation capacity and pluripotent differentiation. Karyotype analysis revealed that two-third of the cell lines carry a normal euploid karyotype, while one-third remained aneuploid throughout the derivation, resulting in eight hESC lines carrying either trisomy 13 (Patau syndrome), 16, 17, 21 (Down syndrome), X (Triple X syndrome), or monosomy X (Turner syndrome). On the basis of the level of single nucleotide polymorphism heterozygosity in the aneuploid chromosomes, we determined whether the aneuploidy originated from meiotic or mitotic chromosomal nondisjunction. Gene expression profiles of the trisomic cell lines suggested that all three chromosomes are actively transcribed. Our analysis allowed us to determine which tissues are most affected by the presence of a third copy of either chromosome 13, 16, 17 or 21 and highlighted the effects of trisomies on embryonic development. The results presented here suggest that aneuploid embryos can serve as an alternative source for either normal euploid or aneuploid hESC lines, which represent an invaluable tool to study developmental aspects of chromosomal abnormalities in humans.

  18. Derivation and characterization of Chinese human embryonic stem cell line with high potential to differentiate into pancreatic and hepatic cells

    Institute of Scientific and Technical Information of China (English)

    SHI Cheng; SHEN Huan; JIANG Wei; SONG Zhi-hua; WANG Cheng-yan; WEI Li-hui

    2011-01-01

    Background Human embryonic stem cells have prospective uses in regenerative medicine and drug screening. Every human embryonic stem cell line has its own genetic background,which determines its specific ability for differentiation as well as susceptibility to drugs. It is necessary to compile many human embryonic stem cell lines with various backgrounds for future clinical use,especially in China due to its large population. This study contributes to isolating new Chinese human embryonic stem cell lines with clarified directly differentiation ability.Methods Donated embryos that exceeded clinical use in our in vitro fertilization-embryo transfer (IVF-ET) center were collected to establish human embryonic stem cells lines with informed consent. The classic growth factors of basic fibroblast growth factor (bFGF) and recombinant human leukaemia inhibitory factor (hLIF) for culturing embryonic stem cells were used to capture the stem cells from the plated embryos. Mechanical and enzymetic methods were used to propogate the newly established human embryonic stem cells line. The new cell line was checked for pluripotent characteristics with detecting the expression of stemness genes and observing spontaneous differentiation both in vitro and in vivo. Finally similar step-wise protocols from definitive endoderm to target specific cells were used to check the cell line's ability to directly differentiate into pancreatic and hepatic cells.Results We generated a new Chinese human embryonic stem cells line,CH1. This cell line showed the same characteristics as other reported Chinese human embryonic stem cells lines:normal morphology,karyotype and pluripotency in vitro and in vivo. The CH1 cells could be directly differentiated towards pancreatic and hepatic cells with equal efficiency compared to the H1 cell line.Conclusions This newly established Chinese cell line,CH1,which is pluripotent and has high potential to differentiate into pancreatic and hepatic cells,will provide

  19. X chromosome inactivation is initiated in human preimplantation embryos

    NARCIS (Netherlands)

    van den Berg, Ilse M; Laven, Joop S E; Stevens, Mary; Jonkers, Iris; Galjaard, Robert-Jan; Gribnau, Joost; van Doorninck, J Hikke

    2009-01-01

    X chromosome inactivation (XCI) is the mammalian mechanism that compensates for the difference in gene dosage between XX females and XY males. Genetic and epigenetic regulatory mechanisms induce transcriptional silencing of one X chromosome in female cells. In mouse embryos, XCI is initiated at the

  20. A comparative study on efficiency of adult fibroblast, putative embryonic stem cell and lymphocyte as donor cells for production of handmade cloned embryos in goat and characterization of putative ntES cells obtained from these embryos.

    Science.gov (United States)

    Dutta, Rahul; Malakar, Dhruba; Khate, Keviletsu; Sahu, Shailendra; Akshey, Yogesh; Mukesh, Manishi

    2011-09-15

    The main purpose of the experiment was to compare the efficiency of three cell types, namely adult fibroblast, putative embryonic stem (ES) cell, and lymphocyte, as donor cells for somatic cell nuclear transfer by handmade cloning in goats. The outcome clearly shows that putative embryonic stem cells, with a cleavage and blastocyst production rate of 74.69% ± 3.92 and 39.75% ± 3.86, respectively, performs better in comparison to adult fibroblast cell and lymphocyte. Between adult fibroblast cell and lymphocyte no statistically significant difference exists at P II DRB genes of cloned embryos and three donor cells were performed to verify the cloned embryos. The amplified PCR products were subjected to SSCP to confirm their genetic identity. The karyotyping of the cloned embryos showed normal chromosomal status as expected in goat. Significantly, in the second stage of the experiment, the produced cloned embryos were successfully used to derive ntES-like cells. The rate of primary colony formation rate was 62.50% ± 4.62 for fibroblast donor cell derived embryos. The same was 60.60% ± 4.62 for putative ES donor cell derived embryos and 66.66% ± 4.62 for lymphocyte donor cell derived embryos, respectively. The putative ntES colonies were positively characterized for alkaline phosphatase, Oct-4, TRA-1-60, TRA-1-81, Sox-2, and Nanog by Immunocytochemistry and Reverse Transcription PCR. To further validate the stem ness, the produced putative ntES colonies were differentiated to embryoid bodies. Immunocytochemistry revealed that embryoid bodies expressed NESTIN specific for ectodermal lineage; GATA-4 for endodermal lineage and smooth muscle actin-I, and troponin-I specific for mesodermal lineage. The study has established an efficient protocol for putative ntES cell derivation from HMC embryos. It could be of substantial significance as patient specific ntES cells have proven therapeutic significance.

  1. Stem cells in the human breast

    DEFF Research Database (Denmark)

    Petersen, Ole William; Polyak, Kornelia

    2010-01-01

    The origins of the epithelial cells participating in the development, tissue homeostasis, and cancer of the human breast are poorly understood. However, emerging evidence suggests a role for adult tissue-specific stem cells in these processes. In a hierarchical manner, these generate the two main...

  2. Lineage-specific interface proteins match up the cell cycle and differentiation in embryo stem cells

    DEFF Research Database (Denmark)

    Re, Angela; Workman, Christopher; Waldron, Levi

    2014-01-01

    The shortage of molecular information on cell cycle changes along embryonic stem cell (ESC) differentiation prompts an in silico approach, which may provide a novel way to identify candidate genes or mechanisms acting in coordinating the two programs. We analyzed germ layer specific gene expression...... interaction data. A new class of non-transcriptionally regulated genes was identified, encoding proteins which interact systematically with proteins corresponding to genes regulated during the cell cycle or cell differentiation, and which therefore can be seen as interface proteins coordinating the two...... changes during the cell cycle and ESC differentiation by combining four human cell cycle transcriptome profiles with thirteen in vitro human ESC differentiation studies. To detect cross-talk mechanisms we then integrated the transcriptome data that displayed differential regulation with protein...

  3. Transcriptomic Analysis Of Purified Embryonic Neural Stem Cells From Zebrafish Embryos Reveals Signalling Pathways Involved In Glycine-dependent Neurogenesis

    Directory of Open Access Journals (Sweden)

    Eric eSAMARUT

    2016-03-01

    Full Text Available How is the initial set of neurons correctly established during the development of the vertebrate central nervous system? In the embryo, glycine and GABA are depolarizing due the immature chloride gradient, which is only reversed to become hyperpolarizing later in post-natal development. We previously showed that glycine regulates neurogenesis via paracrine signalling that promotes calcium transients in neural stem cells (NSCs and their differentiation into interneurons within the spinal cord of the zebrafish embryo. However, the subjacent molecular mechanisms are not yet understood. Our previous work suggests that early neuronal progenitors were not differentiating correctly in the developing spinal cord. As a result, we aimed at identifying the downstream molecular mechanisms involved specifically in NSCs during glycine-dependent embryonic neurogenesis. Using a gfap:GFP transgenic line, we successfully purified NSCs by fluorescence-activated cell sorting (FACS from whole zebrafish embryos and in embryos in which the glycine receptor was knocked down. The strength of this approach is that it focused on the NSC population while tackling the biological issue in an in vivo context in whole zebrafish embryos. After sequencing the transcriptome by RNA-sequencing, we analyzed the genes whose expression was changed upon disruption of glycine signalling and we confirmed the differential expression by independent RTqPCR assay. While over a thousand genes showed altered expression levels, through pathway analysis we identified 14 top candidate genes belonging to five different canonical signalling pathways (signalling by calcium, TGF-beta, sonic hedgehog, Wnt and p53-related apoptosis that are likely to mediate the promotion of neurogenesis by glycine.

  4. Biopsy of human morula-stage embryos: outcome of 215 IVF/ICSI cycles with PGS.

    Directory of Open Access Journals (Sweden)

    Elena E Zakharova

    Full Text Available Preimplantation genetic diagnosis (PGD is commonly performed on biopsies from 6-8-cell-stage embryos or blastocyst trophectoderm obtained on day 3 or 5, respectively. Day 4 human embryos at the morula stage were successfully biopsied. Biopsy was performed on 709 morulae from 215 ICSI cycles with preimplantation genetic screening (PGS, and 3-7 cells were obtained from each embryo. The most common vital aneuploidies (chromosomes X/Y, 21 were screened by fluorescence in situ hybridization (FISH. No aneuploidy was observed in 72.7% of embryos, 91% of those developed to blastocysts. Embryos were transferred on days 5-6. Clinical pregnancy was obtained in 32.8% of cases, and 60 babies were born. Patients who underwent ICSI/PGS treatment were compared with those who underwent standard ICSI treatment by examining the percentage of blastocysts, pregnancy rate, gestational length, birth height and weight. No significant differences in these parameters were observed between the groups. Day 4 biopsy procedure does not adversely affect embryo development in vitro or in vivo. The increased number of cells obtained by biopsy of morulae might facilitate diagnostic screening. There is enough time after biopsy to obtain PGD results for embryo transfer on day 5-6 in the current IVF cycle.

  5. Human Embryonic Stem Cells: A Model for the Study of Neural Development and Neurological Diseases

    Directory of Open Access Journals (Sweden)

    Piya Prajumwongs

    2016-01-01

    Full Text Available Although the mechanism of neurogenesis has been well documented in other organisms, there might be fundamental differences between human and those species referring to species-specific context. Based on principles learned from other systems, it is found that the signaling pathways required for neural induction and specification of human embryonic stem cells (hESCs recapitulated those in the early embryo development in vivo at certain degree. This underscores the usefulness of hESCs in understanding early human neural development and reinforces the need to integrate the principles of developmental biology and hESC biology for an efficient neural differentiation.

  6. 人胚胎移植后剩余胚胎继续体外培养潜能的研究%Potential development to blastocyst of the surplus embryos from human embryo transfer

    Institute of Scientific and Technical Information of China (English)

    薛侠; 赵皖秋; 张四林; 秦臻; 师娟子

    2011-01-01

    Objective To explore the developmental potential of the surplus embryos from human embryo transfer during IVF - ET cycles. Methods All embryos with non - pronucleus (0PN), a single pronudeus (1PN), a number of pronucleus (≥3PN) and 2 pronudeus delaying development in cleavage stage (2PN) were cultured into blastula by the sequential method. Results ① 314 Surplus embryos were collected and formed 152 blastulas(48.41% ) after the sequential culture, among which 53 (34.87%) were high-quality blastula. ② The embryo grade on Day 3 was related to blastocyst rate. The higher embryo grade, the higher blastula formation (54.39%, 52.39%, 49.61% and 21.62% ); ③ Blastocyst formation rates of embryos in 1PN embryos,0PN embryos and D3 from blastocyst embryos classified Ⅲ had higher rates of blastula formation than D3 from blastocyst embryos classified beyond Ⅲ ( P < 0.05). Conclusion Embryos of level Ⅲ and above in D3 are still opportunities for blastocyst formation. The 0PN, 1PN embryo cleavage embryos developed from the D3 can continue to develop in high - quality, until after the formation of blastocysts, and then a pre- implantation genetic diagnosis. If the karyotype is aneuploid karyotype, then it should be frozen or transplanted first. The measures above can improve the oocyte retrieval in patients with accumulation of a single pregnancy, which can also provide resources for embryonic stem cell research.%目的 探讨IVF新鲜周期中D3可用胚胎移植和冷冻后剩余胚胎继续培养的价值.方法 通过囊胚序贯培养法将无原核(0PN)、单个原核(1PN)、多个原核(≥3PN)和卵裂期发育延缓的2原核(2PN)废弃胚胎培养至囊胚期.结果 ① 314枚剩余胚胎于D5~D7形成152枚囊胚(48.41%),其中53枚为优质囊胚(34.87%); ② 胚胎级别越高,囊胚形成率越高(54.39%、52.39%、49.61%和21.62%); ③ 0PN和1PN卵裂发育而来的D3优质胚胎、2PN卵裂发育来的D3评分为Ⅲ级

  7. A novel marker for undifferentiated human embryonic stem cells.

    Science.gov (United States)

    Higashi, Kiyoshi; Yagi, Masaki; Arakawa, Tatsuhiko; Asano, Kouji; Kobayashi, Kumiko; Tachibana, Taro; Saito, Koichi

    2015-02-01

    Human embryonic stem cells (hESCs) are pluripotent stem cells from early embryos, and their self-renewal capacity depends on the sustained expression of hESC-specific molecules and the suppressed expression of differentiation-associated genes. To discover novel molecules expressed on hESCs, we generated a panel of monoclonal antibodies against undifferentiated hESCs. The antigen recognized by MAb2 is expressed on the cell surface of undifferentiated hESCs; three diffused bands with molecular mass between 30 and 60 kDa in the lysates of hESCs were diminished during hESC differentiation into neural cells. The expression of MAb2 antigen was also observed on the plasma membrane of lung cancer cells, and MAb2 detected 55, 50, and 35 kDa protein bands in the cell lysates. Immunoprecipitation followed by proteomics analyses identified CD147/basigin as a MAb2 antigen. Finally, the positive expression of CD147/basigin protein in undifferentiated hESCs was confirmed. These results suggested that CD147/basigin could be another undifferentiated hESC marker.

  8. Self-Organization of Spatial Patterning in Human Embryonic Stem Cells.

    Science.gov (United States)

    Deglincerti, Alessia; Etoc, Fred; Ozair, M Zeeshan; Brivanlou, Ali H

    2016-01-01

    The developing embryo is a remarkable example of self-organization, where functional units are created in a complex spatiotemporal choreography. Recently, human embryonic stem cells (ESCs) have been used to recapitulate in vitro the self-organization programs that are executed in the embryo in vivo. This represents an unique opportunity to address self-organization in humans that is otherwise not addressable with current technologies. In this chapter, we review the recent literature on self-organization of human ESCs, with a particular focus on two examples: formation of embryonic germ layers and neural rosettes. Intriguingly, both activation and elimination of TGFβ signaling can initiate self-organization, albeit with different molecular underpinnings. We discuss the mechanisms underlying the formation of these structures in vitro and explore future challenges in the field.

  9. Reasoning about embryos, cloning and stem cells: let's get more clear and distinct.

    Science.gov (United States)

    Parker, Malcolm

    2003-01-01

    Plural democratic societies encourage and require the tolerance of disparate views. However, in relation to contentious areas like assisted reproductive technologies and destructive embryo research, tolerance is strained by the normative force of our fundamental beliefs about the moral status of early human forms. Yet in the continuing debates, spokespersons for different positions often do not concede all the implications of their arguments, may sidestep the real moral issues, and can fail to be clear about the foundations on which their arguments and policy advice ultimately rely. Guidelines and statutes can be rendered incoherent by the desire to balance and satisfy opposing values, rather than honestly reflecting the primary values they espouse. I call for greater clarity and honesty as these issues continue to be debated. An uncritical adherence to pluralism will encourage strategic obfuscation, but citizens of democracies need to be clearly informed about all the premises of opposing positions. Decisions about ethically and legally acceptable reproductive technologies ultimately depend on support for one metaphysical grounding at the expense of another. This should be acknowledged, as should its implications for policy.

  10. Induction of human umbilical cord blood-derived stem cells with embryonic stem cell phenotypes into insulin producing islet-like structure.

    Science.gov (United States)

    Sun, Bo; Roh, Kyung-Hwan; Lee, Sae-Rom; Lee, Yong-Soon; Kang, Kyung-Sun

    2007-03-23

    Success in islet-transplantation-based therapies for type I diabetes, coupled with a worldwide shortage of transplant-ready islets, has motivated efforts to develop renewable sources of islet-replacement tissue. Embryonic stem cells (ESCs) have been successfully induced into insulin producing islet-like structure in several studies. However, the source of the ESCs has presented ethical and technical concerns. Here, we isolated a population of stem cells from human cord blood (UCB), which expressed embryo stage specific maker, SSEA-4, and the multi-potential stem cell marker, Oct4. Subsequently, we successfully induced them into insulin-producing islet-like structures, which co-express insulin and C-peptide. These findings might have a significant potential to advance human UCB derived stem-cell-based therapeutics for diabetes.

  11. An in vivo culture system for human embryos using an encapsulation technology: a pilot study

    Science.gov (United States)

    Blockeel, C.; Mock, P.; Verheyen, G.; Bouche, N.; Le Goff, Ph.; Heyman, Y.; Wrenzycki, C.; Höffmann, K.; Niemann, H.; Haentjens, P.; de Los Santos, M.J.; Fernandez-Sanchez, M.; Velasco, M.; Aebischer, P.; Devroey, P.; Simón, C.

    2009-01-01

    BACKGROUND Animal studies have demonstrated better embryo development in vivo than in vitro. This pilot study tested the feasibility of using a novel in utero culture system (IUCS) to obtain normal human fertilization and embryo development. METHODS The IUCS device comprised a perforated silicone hollow tube. The study included 13 patients (<36 years) undergoing a first intracytoplasmic sperm injection (ICSI) treatment and 167 metaphase II oocytes in three groups. In Group 1, 1–2 h after ICSI, sibling oocytes were assigned to IUCS or conventional in vitro culture. The device was retrieved on Day 1, and all zygotes were cultured in vitro till Day 5. In Group 2, fertilized oocytes were assigned on Day 1, embryos retrieved on Day 3 and all embryos cultured till Day 5. In Group 3, after Day 0 assignment, embryos were retrieved on Day 3 for blastomere biopsy and fluorescence in situ hybridization (FISH) and cultured until Day 5. The highest quality blastocysts were transferred on Day 5. RESULTS Fertilization and embryo development were comparable in the in vitro and IUCS arms, with a tendency towards better embryo quality in the IUCS. FISH analysis in Group 3 revealed more normal embryos using the IUCS (P = 0.049). Three clinical pregnancies and live births were obtained: two from the IUCS arm and one from the in vitro arm. CONCLUSIONS Our pilot study shows that this new IUCS appears to be feasible and safe, supporting normal fertilization, embryo development and normal chromosomal segregation. Furthermore, live births are possible after the transient presence of a silicone device in the uterus.Clinicaltrials.gov: NCT00480103. PMID:19273881

  12. Polarity and cell division orientation in the cleavage embryo: from worm to human

    Science.gov (United States)

    Ajduk, Anna; Zernicka-Goetz, Magdalena

    2016-01-01

    Cleavage is a period after fertilization, when a 1-cell embryo starts developing into a multicellular organism. Due to a series of mitotic divisions, the large volume of a fertilized egg is divided into numerous smaller, nucleated cells—blastomeres. Embryos of different phyla divide according to different patterns, but molecular mechanism of these early divisions remains surprisingly conserved. In the present paper, we describe how polarity cues, cytoskeleton and cell-to-cell communication interact with each other to regulate orientation of the early embryonic division planes in model animals such as Caenorhabditis elegans, Drosophila and mouse. We focus particularly on the Par pathway and the actin-driven cytoplasmic flows that accompany it. We also describe a unique interplay between Par proteins and the Hippo pathway in cleavage mammalian embryos. Moreover, we discuss the potential meaning of polarity, cytoplasmic dynamics and cell-to-cell communication as quality biomarkers of human embryos. PMID:26660321

  13. Prediction model for aneuploidy in early human embryo development revealed by single-cell analysis

    Science.gov (United States)

    Vera-Rodriguez, Maria; Chavez, Shawn L.; Rubio, Carmen; Pera, Renee A. Reijo; Simon, Carlos

    2015-01-01

    Aneuploidies are prevalent in the human embryo and impair proper development, leading to cell cycle arrest. Recent advances in imaging and molecular and genetic analyses are postulated as promising strategies to unveil the mechanisms involved in aneuploidy generation. Here we combine time-lapse, complete chromosomal assessment and single-cell RT–qPCR to simultaneously obtain information from all cells that compose a human embryo until the approximately eight-cell stage (n=85). Our data indicate that the chromosomal status of aneuploid embryos (n=26), including those that are mosaic (n=3), correlates with significant differences in the duration of the first mitotic phase when compared with euploid embryos (n=28). Moreover, gene expression profiling suggests that a subset of genes is differentially expressed in aneuploid embryos during the first 30 h of development. Thus, we propose that the chromosomal fate of an embryo is likely determined as early as the pronuclear stage and may be predicted by a 12-gene transcriptomic signature. PMID:26151134

  14. Integrating insulin into single-step culture medium regulates human embryo development in vitro.

    Science.gov (United States)

    Fawzy, Mohamed; Sabry, Mohamed; Nour, Mohamed; Abdelrahman, Mohamed Y; Roshdy, Eman; Magdi, Yasmin; Abdelghafar, Hazem

    2017-02-01

    To evaluate the effect of supplementing single-step embryo culture medium with insulin on human embryo development. Comparative study. Two private centers. The study involved a sibling oocyte split of 5,142 retrieved oocytes from 360 patients. Sibling oocytes split after intracytoplasmic sperm injection for culture from day 0 through day 5 or 6 in insulin-supplemented or control medium. Women were split to receive their embryos from insulin-supplemented or control medium. Clinical pregnancy rate. There were significantly higher rates of clinical, ongoing, and twin pregnancies in the insulin-supplemented arm than in the control arm. On day 3, embryo quality and compaction were higher in insulin-supplemented medium. On day 5, insulin supplementation showed higher rates of blastocyst formation, quality, and cryopreservation. Insulin supplementation of single-step embryo culture medium from day 0 through day 5 or 6 improved clinical pregnancy rate and human embryo development. However, these findings need further confirmation through a multicenter randomized controlled trial that may include other patient populations and different culture media. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  15. Optimized protocol for derivation of human embryonic stem cell lines.

    Science.gov (United States)

    Camarasa, María Vicenta; Galvez, Víctor Miguel; Brison, Daniel Roy; Bachiller, Daniel

    2012-09-01

    For the past 12 years, the biology and applications of human embryonic stem cells (hESCs) have received great attention from the scientific community. Derivatives of the first hESC line obtained by J. Thomson's group (Science 282(5391):1145-1147, 1998) have been used in clinical trials in patients with spinal cord injury, and other hESC lines have now been used to generate cells for use in treating blindness (Lancet 379(9817):713-720, 2012). In addition to the classical protocol based on mouse or human feeder layers using open culture methods (In Vitro Cellular & Developmental Biology - Animal 46(3-4):386-394, 2010; Stem Cells 23(9):1221-1227, 2005; Nature Biotechnology 24(2):185-187, 2006; Human Reproduction 21(2):503-511, 2006; Human Reproduction 20(8):2201-2206, 2005; Fertility and Sterility 83(5):1517-1529, 2005), novel hESC lines have been derived xeno-free (without using animal derived reagents) (PLoS One 5 (4):1024-1026, 2010), feeder-free (without supporting cell monolayers) (Lancet 365(9471):1601-1603, 2005), in microdrops under oil (In Vitro Cellular & Developmental Biology - Animal 46(3-4):236-41, 2010) and in suspension with ROCK inhibitor (Nature Biotechnology 28(4):361-4, 2010). Regardless of the culture system, successful hESC derivation usually requires optimization of embryo culture, the careful and timely isolation of its inner cell mass (ICM), and precise culture conditions up to the establishment of pluripotent cell growth during hESC line derivation. Herein we address the crucial steps of the hESC line derivation protocol, and provide tips to apply quality control to each step of the procedure.

  16. Neural differentiation of embryonic stem cells in vitro: a road map to neurogenesis in the embryo.

    Directory of Open Access Journals (Sweden)

    Elsa Abranches

    Full Text Available BACKGROUND: The in vitro generation of neurons from embryonic stem (ES cells is a promising approach to produce cells suitable for neural tissue repair and cell-based replacement therapies of the nervous system. Available methods to promote ES cell differentiation towards neural lineages attempt to replicate, in different ways, the multistep process of embryonic neural development. However, to achieve this aim in an efficient and reproducible way, a better knowledge of the cellular and molecular events that are involved in the process, from the initial specification of neuroepithelial progenitors to their terminal differentiation into neurons and glial cells, is required. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we characterize the main stages and transitions that occur when ES cells are driven into a neural fate, using an adherent monolayer culture system. We established improved conditions to routinely produce highly homogeneous cultures of neuroepithelial progenitors, which organize into neural tube-like rosettes when they acquire competence for neuronal production. Within rosettes, neuroepithelial progenitors display morphological and functional characteristics of their embryonic counterparts, namely, apico-basal polarity, active Notch signalling, and proper timing of production of neurons and glia. In order to characterize the global gene activity correlated with each particular stage of neural development, the full transcriptome of different cell populations that arise during the in vitro differentiation protocol was determined by microarray analysis. By using embryo-oriented criteria to cluster the differentially expressed genes, we define five gene expression signatures that correlate with successive stages in the path from ES cells to neurons. These include a gene signature for a primitive ectoderm-like stage that appears after ES cells enter differentiation, and three gene signatures for subsequent stages of neural progenitor

  17. Factors affecting the gene expression of in vitro cultured human preimplantation embryos

    NARCIS (Netherlands)

    Mantikou, E.; Jonker, M.J.; Wong, K.M.; van Montfoort, A.P.A.; de Jong, M.; Breit, T.M.; Repping, S.; Mastenbroek, S.

    2016-01-01

    STUDY QUESTION: What is the relative effect of common environmental and biological factors on transcriptome changes during human preimplantation development? SUMMARY ANSWER: Developmental stage and maternal age had a larger effect on the global gene expression profile of human preimplantation embryo

  18. Future research and therapeutic applications of human stem cells: general, regulatory, and bioethical aspects

    Directory of Open Access Journals (Sweden)

    Liras Antonio

    2010-12-01

    Full Text Available Abstract There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases. Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell and the efficacy (maximum effect and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further

  19. Stem cells expanded from the human embryonic hindbrain stably retain regional specification and high neurogenic potency.

    Science.gov (United States)

    Tailor, Jignesh; Kittappa, Raja; Leto, Ketty; Gates, Monte; Borel, Melodie; Paulsen, Ole; Spitzer, Sonia; Karadottir, Ragnhildur Thora; Rossi, Ferdinando; Falk, Anna; Smith, Austin

    2013-07-24

    Stem cell lines that faithfully maintain the regional identity and developmental potency of progenitors in the human brain would create new opportunities in developmental neurobiology and provide a resource for generating specialized human neurons. However, to date, neural progenitor cultures derived from the human brain have either been short-lived or exhibit restricted, predominantly glial, differentiation capacity. Pluripotent stem cells are an alternative source, but to ascertain definitively the identity and fidelity of cell types generated solely in vitro is problematic. Here, we show that hindbrain neuroepithelial stem (hbNES) cells can be derived and massively expanded from early human embryos (week 5-7, Carnegie stage 15-17). These cell lines are propagated in adherent culture in the presence of EGF and FGF2 and retain progenitor characteristics, including SOX1 expression, formation of rosette-like structures, and high neurogenic capacity. They generate GABAergic, glutamatergic and, at lower frequency, serotonergic neurons. Importantly, hbNES cells stably maintain hindbrain specification and generate upper rhombic lip derivatives on exposure to bone morphogenetic protein (BMP). When grafted into neonatal rat brain, they show potential for integration into cerebellar development and produce cerebellar granule-like cells, albeit at low frequency. hbNES cells offer a new system to study human cerebellar specification and development and to model diseases of the hindbrain. They also provide a benchmark for the production of similar long-term neuroepithelial-like stem cells (lt-NES) from pluripotent cell lines. To our knowledge, hbNES cells are the first demonstration of highly expandable neuroepithelial stem cells derived from the human embryo without genetic immortalization.

  20. Reflections on the United States National Institutes of Health draft guidelines for research involving human pluripotent stem cells--theological perspective.

    Science.gov (United States)

    Sotis, J J

    2000-01-01

    Since the human embryonic stem cell research involves destruction of human embryos and, therefore, hinges on the fundamental question of the status of the embryo, it is essential to examine this status carefully in order to establish fitting guidelines for research. The US National Institutes of Health has proposed its own guidelines on the matter recently (1999). The document, rooted in current pluralistic perspectives in moral philosophy (or bioethics), is criticised in this paper as morally inadequate. The argumentation of the criticism stems from the theological perspective on human personhood, which focuses on a continuity of personal identity from embryos to adult human beings. An additional concern for the author is the moral complicity in which the research dependent upon the destruction of human embryonic life is sanctioned.

  1. Toxicological and melanin synthesis effects of Polygonum multiflorum root extracts on zebrafish embryos and human melanocytes

    Directory of Open Access Journals (Sweden)

    Thanh Thi Hoai Dang

    2016-09-01

    Full Text Available Polygonum multiflorum (PM has been commmonly used as folk medicine for treatment of various conditions, such as early graying of hair in humans. However, there have been limited studies which have evaluated the toxicological and biological effects of PM in vitro as well as in vivo. In this study, PM root extracts in ethyl acetate (PM-E and in distilled water (PM-W were examined for their effects on the development of teratogenic defects/deaths. Additionally, they were evaluated for their effects on melanin formation in human melanocytes and pigmentation in embryos/larvae of wild type strain AB zebrafish (Danio rerio. Our results showed that PM root extracts at concentrations of 40 mg/L and 105 mg/L induced the development of teratogenic defects, including yolk sac edema (or heart edema, hemovascular defects, necrosis and abnormal trunk in zebrafish embryos at 4 days post fertilization; teratogenic indexes (TIs were 1.43 and 0.63 for ethyl acetate extract and distilled water extract, respectively. Our results also demonstrated that PM-W significantly increased the pigmentation level of embryos/larvae and induced melanin formation in human melanocytes. The amount of melanin in PM-W-exposed embryos/larvae was 2.2-fold and 1.71-fold greater than those in the control embryos/larvae and control melanocytes, respectively. Our study also showed that the increased level of pigmentation in PM-W embryos/larvae or melanin biosynthesis in melanocytes were both regulated by activation of tyrosinase. Conclusively, our study suggests that PM root extracts could be used as potential agents for treatment of early hair graying as well as various other diseases related to loss of pigmentation. However, these PM root extracts may also have some negative effects on embryos; therefore it should be careful when using for women during pregnancy. [Biomed Res Ther 2016; 3(9.000: 808-818

  2. Identification of chromosomal errors in human preimplantation embryos with oligonucleotide DNA microarray.

    Directory of Open Access Journals (Sweden)

    Lifeng Liang

    Full Text Available A previous study comparing the performance of different platforms for DNA microarray found that the oligonucleotide (oligo microarray platform containing 385K isothermal probes had the best performance when evaluating dosage sensitivity, precision, specificity, sensitivity and copy number variations border definition. Although oligo microarray platform has been used in some research fields and clinics, it has not been used for aneuploidy screening in human embryos. The present study was designed to use this new microarray platform for preimplantation genetic screening in the human. A total of 383 blastocysts from 72 infertility patients with either advanced maternal age or with previous miscarriage were analyzed after biopsy and microarray. Euploid blastocysts were transferred to patients and clinical pregnancy and implantation rates were measured. Chromosomes in some aneuploid blastocysts were further analyzed by fluorescence in-situ hybridization (FISH to evaluate accuracy of the results. We found that most (58.1% of the blastocysts had chromosomal abnormalities that included single or multiple gains and/or losses of chromosome(s, partial chromosome deletions and/or duplications in both euploid and aneuploid embryos. Transfer of normal euploid blastocysts in 34 cycles resulted in 58.8% clinical pregnancy and 54.4% implantation rates. Examination of abnormal blastocysts by FISH showed that all embryos had matching results comparing microarray and FISH analysis. The present study indicates that oligo microarray conducted with a higher resolution and a greater number of probes is able to detect not only aneuploidy, but also minor chromosomal abnormalities, such as partial chromosome deletion and/or duplication in human embryos. Preimplantation genetic screening of the aneuploidy by DNA microarray is an advanced technology used to select embryos for transfer and improved embryo implantation can be obtained after transfer of the screened normal

  3. Generation of KCL035 research grade human embryonic stem cell line carrying a mutation in HBB gene

    Directory of Open Access Journals (Sweden)

    Heema Hewitson

    2016-03-01

    Full Text Available The KCL035 human embryonic stem cell line was derived from an embryo donated for research that carried a mutation in the HBB gene, which is linked to the β-thalassemia syndrome. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  4. Derivation of naive human embryonic stem cells.

    Science.gov (United States)

    Ware, Carol B; Nelson, Angelique M; Mecham, Brigham; Hesson, Jennifer; Zhou, Wenyu; Jonlin, Erica C; Jimenez-Caliani, Antonio J; Deng, Xinxian; Cavanaugh, Christopher; Cook, Savannah; Tesar, Paul J; Okada, Jeffrey; Margaretha, Lilyana; Sperber, Henrik; Choi, Michael; Blau, C Anthony; Treuting, Piper M; Hawkins, R David; Cirulli, Vincenzo; Ruohola-Baker, Hannele

    2014-03-25

    The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222-9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible.

  5. Human cytomegalovirus induces alteration of (-actin mRNA and microfilaments in human embryo fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    林茂芳; 魏国庆; 黄河; 蔡真

    2004-01-01

    Objective: To investigate the infection of human embryo fibroblast cell line HF cells by CMV as well as the effects of CMV on β-actin mRNA and microfilaments. Methods: HF cells shape was observed after the infection of CMV. RT-PCR assay was used to detect the mRNA expression of CMV immediate early (IE) gene, β-actin and GAPDH genes of HF cells infected by CMV. CMV particles and cell microfilaments were detected with electron microscope. Results: Shape of HF cell changed after the infection by CMV. HF cells infected by CMV could express IE mRNA and the expression of β-actin mRNA decreased in a time- and titer-dependent manner compared with the uninfected HF cells whose expression of GAPDH mRNA did not change much. CMV particles were found with electron microscope in the cells. Microfilaments were ruptured and shortened after the infection of CMV. Conclusion: CMV can not only infect human embryo fibroblast cells line HF cells and replicate in the cells, but can also affect the expression of β-actin mRNA and the microfilaments.

  6. Human pluripotent stem cells in contemporary medicine

    Directory of Open Access Journals (Sweden)

    S. A. Rodin

    2015-01-01

    Full Text Available Human pluripotent stem cells (hPSCs are capable of indefinite proliferation and can be differentiated into any cell type of the human body. Therefore, they are a promising source of cells for treatment of numerous degenerative diseases and injuries. Pluripotent stem cells are also associated with a number of ethical, safety and technological issues. In this review, we describe various types of hPSCs, safety issues that concern all or some types of hPSCs and methods of clinical-grade hPSC line development. Also, we discuss current and past clinical trials involving hPSCs, their outcomes and future perspectives of hPSC-based therapy. 

  7. The origins of genetic variation between individual human oocytes and embryos: implications for infertility.

    Science.gov (United States)

    Delhanty, Joy D A

    2013-12-01

    Human fertility is low in comparison with that seen in other well-studied mammals. The main reason for this state of affairs seems to be the frequent occurrence and persistence of chromosomal errors in the human conceptus. Evidence obtained over the past two decades shows that the exceptionally high incidence of chromosomal anomalies seen in human preimplantation embryos is the result of errors that may occur at various stages during gamete and embryo formation. In rare cases, an error may exist or arise in the premeiotic germ cells; much more commonly it may arise during the first or second meiotic division in the male or female. Highly efficient cell cycle checkpoints in the male ensure that the incidence of aneuploidy in mature sperm is low compared to that in the oocyte. Most 3-day-old embryos created by IVF are chromosomal mosaics, and this persists to a lesser degree to the blastocyst stage on day 5. While aneuploidy of meiotic origin is a major factor affecting the fertility of older women, embryos from most younger women will have predominantly post-zygotic mitotic errors. Couples experiencing RIF are particularly likely to produce highly abnormal (chaotic) embryos by post-zygotic mechanisms.

  8. The Singapore approach to human stem cell research, therapeutic and reproductive cloning.

    Science.gov (United States)

    Kian, Catherine Tay Swee; Leng, Tien Sim

    2005-06-01

    With the controversial ethical issues on the creation of human embryos through cloning for therapeutic research, which holds more promise of medical breakthroughs that the world could ever imagine and the acknowledgement by many scientists that this technology may not lead in the near future to therapies; this country report discusses the approach Singapore takes on human stem cell research, interjected with the authors' own arguments and suggestions especially on research compensation injuries, an often neglected important issue. International comparative viewpoints taken by the major countries in the world are also included in the appendix.

  9. Concise review: animal substance-free human embryonic stem cells aiming at clinical applications.

    Science.gov (United States)

    Hovatta, Outi; Rodin, Sergey; Antonsson, Liselotte; Tryggvason, Karl

    2014-11-01

    Human embryonic stem cells have been considered the gold standard as a cell source for regenerative medicine since they were first cultured in 1998. They are pluripotent and can form principally all the cells types in the body. They are obtained from supernumerary human in vitro fertilization embryos that cannot be used for infertility treatment. Following studies on factors regulating pluripotency and differentiation, we now have techniques to establish and effectively expand these cells in animal substance-free conditions, even from single cells biopsied from eight-cell stage embryos in chemically defined feeder-free cultures. The genetic stability and absence of tumorigenic mutations can be determined. There are satisfactory animal tests for functionality and safety. The first clinical trials are ongoing for two indications: age-related macular degeneration and spinal cord injury. ©AlphaMed Press.

  10. Radiation response of mesenchymal stem cells derived from bone marrow and human pluripotent stem cells

    OpenAIRE

    Islam, Mohammad S; Stemig, Melissa E.; Takahashi, Yutaka; Hui, Susanta K.

    2014-01-01

    Mesenchymal stem cells (MSCs) isolated from human pluripotent stem cells are comparable with bone marrow-derived MSCs in their function and immunophenotype. The purpose of this exploratory study was comparative evaluation of the radiation responses of mesenchymal stem cells derived from bone marrow- (BMMSCs) and from human embryonic stem cells (hESMSCs). BMMSCs and hESMSCs were irradiated at 0 Gy (control) to 16 Gy using a linear accelerator commonly used for cancer treatment. Cells were harv...

  11. Effect of oxygen concentration on human embryo development evaluated by time-lapse monitoring

    DEFF Research Database (Denmark)

    Ingerslev, Hans Jakob; Hindkjær, Johnny Juhl; Kirkegaard, Kirstine

    2012-01-01

    -points are given as hours after fertilisation Results: The timing of the first two cleavage cycles resulting in a 4-cell embryo was not significantly different between the groups. The timing of the third cleavage cycle, i.e. division to 5, 6, 7 and 8 cells was delayed for embryos cultured in 20% oxygen (P5cell =0......Introduction: Data from a number of studies indicate -but not unequivocally- that culture of embryos in 5% O2 compared to 20% O2 improves blastocyst formation in humans and various animal species and may yield better pregnancy rates in IVF. The detrimental effects of atmospheric oxygen were...... recently demonstrated to occur from first cleavage cycle in mice using time-lapse microscopy, with the largest impact on the pre-compaction stages. However, embryonic development in mice differs in many aspects from human embryonic development. The objective of this retrospective, descriptive study...

  12. Assessment of aneuploidy in human oocytes and preimplantation embryos by chromosome painting

    Energy Technology Data Exchange (ETDEWEB)

    Rougier, N.; Viegas-Pequignot, E.; Plachot, M. [Hospital Necker, Paris (France)] [and others

    1994-09-01

    The poor quality of chromosome preparations often observed after fixation of oocytes and embryos did not usually allow accurate identification of chromosomes involved in non-disjunctions. We, therefore, used chromosome painting to determine the incidence of abnormalities for chromosomes 1 and 7. A total of 50 oocytes inseminated for IVF and showing no signs of fertilization as well as 37 diploid embryos donated for research were fixed according to the Dyban`s technique. Fluorescence in situ hybridization was carried out using whole chromosome painting DNA probes specific for human chromosome 1 and 7. The incidence of aneuploidy was 28%, 10% and 60% for metaphase II, polar body and sperm chromosomes, respectively. The high incidence of aneuploidy observed in sperm prematurely condensed sperm chromosomes is due to the fact that usually far less than 23 sperm chromatids are observed, maybe as a consequence of incomplete chromosome condensation. Thirty seven embryos were analyzed with the same probes. 48% of early embryos were either monosomic 1 or 7 or mosaics comprising blastomeres with 1, 2 or 3 signals. Thus, 8 among the 11 abnormal embryos had hypodiploid cells (25 to 37 chromosomes) indicating either an artefactual loss of chromosomes or a complex anomaly of nuclear division (maltinucleated blastomeres, abnormal migration of chromosomes at anaphase). We therefore calculated a {open_quotes}corrected{close_quotes} incidence of aneuploidy for chromosomes 1 or 7 in early embryos: 18%. 86% of the blastocysts showed mosaicism 2n/3 or 4n as a consequence of the formation of the syncitiotrophoblast. To conclude, chromosome painting is an efficient method to accurately identify chromosomes involved in aneuploidy. This technique should allow us to evaluate the incidence of non-disjunction for all chromosome pairs. Our results confirm the high incidence of chromosome abnormalities occurring as a consequence of meiotic or mitotic non-disjunctions in human oocytes and embryos.

  13. Promoting Cas9 degradation reduces mosaic mutations in non-human primate embryos

    Science.gov (United States)

    Tu, Zhuchi; Yang, Weili; Yan, Sen; Yin, An; Gao, Jinquan; Liu, Xudong; Zheng, Yinghui; Zheng, Jiezhao; Li, Zhujun; Yang, Su; Li, Shihua; Guo, Xiangyu; Li, Xiao-Jiang

    2017-01-01

    CRISPR-Cas9 is a powerful new tool for genome editing, but this technique creates mosaic mutations that affect the efficiency and precision of its ability to edit the genome. Reducing mosaic mutations is particularly important for gene therapy and precision genome editing. Although the mechanisms underlying the CRSIPR/Cas9-mediated mosaic mutations remain elusive, the prolonged expression and activity of Cas9 in embryos could contribute to mosaicism in DNA mutations. Here we report that tagging Cas9 with ubiquitin-proteasomal degradation signals can facilitate the degradation of Cas9 in non-human primate embryos. Using embryo-splitting approach, we found that shortening the half-life of Cas9 in fertilized zygotes reduces mosaic mutations and increases its ability to modify genomes in non-human primate embryos. Also, injection of modified Cas9 in one-cell embryos leads to live monkeys with the targeted gene modifications. Our findings suggest that modifying Cas9 activity can be an effective strategy to enhance precision genome editing. PMID:28155910

  14. PROPOSALS FOR EMBRYONIC STEM CELL PRODUCTION WITHOUT DESTROYING HUMAN EMBRYOS: SCIENTIFIC AND BIOETHICAL CHALLENGES PROPUESTAS DE PRODUCCIÓN DE CÉLULAS MADRE EMBRIONARIAS SIN DESTRUIR EMBRIONES HUMANOS: RETOS CIENTÍFICOS Y BIOÉTICOS PROPOSTAS DE PRODUÇÃO DE CÉLULAS-TRONCO EMBRIONÁRIAS SEM DESTRUIR EMBRIÕES HUMANOS: DESAFIOS CIENTÍFICOS E BIOÉTICOS

    Directory of Open Access Journals (Sweden)

    Patricio Ventura-Juncá

    2009-11-01

    Full Text Available The possibility of using human embryonic stem cells (ESC for therapeutic purposes raises serious ethical objections, the most fundamental one being that until recently the only way to obtain ESC was with procedures that necessarily destroyed living human embryos. Due to this, research in this field has been rejected by many scientists, bioeticists, and has been banned by law in several countries. Efforts have been made to find procedures to obtain ESC without destroying embyros or putting them at risk. This paper reviews the scientific, technical and ethical aspects of the different strategies developed for this purpose. Embryo biopsy, ESC obtained from "dead" embryos, ESC produced by "parthenogenetic embryos", ESC obtained by Altered Nuclear Transfer and induced pluripotent cells (iPSC obtained by direct epigenetic reprogramming of somatic cells are the main five alternative reported in recent studies.La posibilidad de usar células madre embrionarias humanas (ESC para finalidades terapéuticas plantea graves objeciones éticas; la más fundamental es que, hasta hace poco, la única manera de obtener ESC era mediante procedimientos que destruían necesariamente embriones humanos vivos. Debido a esto, la investigación en este campo ha sido rechazada por muchos científicos, bioeticistas y ha sido prohibida por ley en varios países. Se han realizado esfuerzos para encontrar procedimientos que permitan obtener ESC sin destruir embriones o sin ponerlos en riesgo. En este documento examinamos los aspectos científicos, técnicos y éticos de las diferentes estrategias elaboradas para esta finalidad. La biopsia de embriones, ESC obtenidas de embriones "muertos"; ESC producidas por partenogénesis de embriones; ESC obtenidas mediante Transferencia Nuclear Alterada y células pluripotentes inducidas (iPSC, obtenidas mediante la reprogramación epigenética directa de las células somáticas, son las principales cinco opciones informadas en estudios

  15. Characterization of human PGD blastocysts with unbalanced chromosomal translocations and human embryonic stem cell line derivation?

    Science.gov (United States)

    Frydman, N; Féraud, O; Bas, C; Amit, M; Frydman, R; Bennaceur-Griscelli, A; Tachdjian, G

    2009-01-01

    Novel embryonic stem cell lines derived from embryos carrying structural chromosomal abnormalities obtained after preimplantation genetic diagnosis (PGD) are of interest to study in terms of the influence of abnormalities on further development. A total of 22 unbalanced blastocysts obtained after PGD were analysed for structural chromosomal defects. Morphological description and chromosomal status of these blastocysts was established and they were used to derive human embryonic stem cell (ESC) lines. An outgrowth of cells was observed for six blastocysts (6/22; 27%). For two blastocysts, the exact morphology was unknown since they were at early stage, and for four blastocysts, the inner cell mass was clearly visible. Fifteen blastocysts carried an unbalanced chromosomal defect linked to a reciprocal translocation, resulting in a positive outgrowth of cells for five blastocysts. One human ESC line was obtained from a blastocyst carrying a partial chromosome-21 monosomy and a partial chromosome-1 trisomy. Six blastocysts carried an unbalanced chromosomal defect linked to a Robertsonian translocation, and one showed a positive outgrowth of cells. One blastocyst carried an unbalanced chromosomal defect linked to an insertion and no outgrowth was observed. The efficiency of deriving human ESC lines with constitutional chromosomal disorders was low and probably depends on the initial morphological aspect of the blastocysts and/or the type of the chromosomal disorders.

  16. Assessment of early cleaving in vitro fertilized human embryos at the 2-cell stage before transfer improves embryo selection.

    Science.gov (United States)

    Sakkas, D; Percival, G; D'Arcy, Y; Sharif, K; Afnan, M

    2001-12-01

    To determine the most viable embryos for transfer. Study 1: Preselection of early-cleaving 2-cell embryos for transfer. Study 2: Alternating weeks during which preselection was performed and not performed. ART program, Birmingham Women's Hospital, Birmingham, United Kingdom. Patients undergoing IVF or ICSI cycles with transfer on day 2. Culture of all fertilized embryos. Number of fertilized embryos cleaving to the 2-cell stage on day 1, embryo quality, implantation rates, and pregnancy rates. Patients with early-cleaving 2-cell embryos had significantly higher pregnancy and implantation rates (45 of 100 [45.0%] and 58 of 219 [25.5%], respectively) than did patients without early-cleaving 2-cell embryos (31 of 130 [23.8%] and 43 of 290 [14.8%], respectively). In weeks during which preselection was used, the overall pregnancy and implantation rates of the clinic improved. The presence of early-cleaving 2-cell embryos improves a patient's chance of achieving pregnancy. Use of more stringent embryo selection criteria can improve overall pregnancy rates.

  17. Human embryonic stem cells and patent protection

    Directory of Open Access Journals (Sweden)

    Radovanović Sanja M.

    2015-01-01

    Full Text Available Given the importance of biotechnological research in modern diagnostics and therapeutics, on the one hand, and stimulative function of a patent, on the other hand, this work deals with the question of the possibility of pa-tent protection of human embryonic stem cells. Taking into account that this is a biotechnological invention, the key question that this paper highlights is the interpretation of the provisions of their patentability. Namely, thanks to the advanced methods of isolation, purification and preparation for implementation, modern patent systems do not exclude a priori living organisms from patent protection. Therefore, the analysis of representative administrative decisions or court rulings sought to define the criteria that would be applied in order to give patent protection to a certain biotechnological invention (stem cells while others do not.

  18. Human embryonic stem cells for neuronal repair.

    Science.gov (United States)

    Ben-Hur, Tamir

    2006-02-01

    Human embryonic stem cells may serve as a potentially endeless source of transplantable cells to treat various neurologic disorders. Accumulating data have shown the therapeutic value of various neural precursor cell types in experimental models of neurologic diseases. Tailoring cell therapy for specific disorders requires the generation of cells that are committed to specific neural lineages. To this end, protocols were recently developed for the derivation of dopaminergic neurons, spinal motor neurons and oligodendrocytes from hESC. These protocols recapitulate normal development in culture conditions. However, a novel concept emerging from these studies is that the beneficial effect of transplanted stem cells is not only via cell replacement in damaged host tissue, but also by trophic and protective effects, as well as by an immunomodulatory effect that down-regulates detrimental brain inflammation.

  19. Effect of in vitro culture of human embryos on birthweight of newborns

    NARCIS (Netherlands)

    Dumoulin, John C.; Land, Jolande A.; Van Montfoort, Aafke P.; Nelissen, Ewka C.; Coonen, Edith; Derhaag, Josien G.; Schreurs, Inge L.; Dunselman, Gerard A.; Kester, Arnold D.; Geraedts, Joep P.; Evers, Johannes L.

    In animal models, in vitro culture of preimplantation embryos has been shown to be a risk factor for abnormal fetal outcome, including high and low birthweight. In the human, mean birthweight of singletons after in vitro fertilization (IVF) is considerably lower than after natural conception, but it

  20. Aneuploidy screening of human IVF embryos: Cytogenetic aspects and clinical implications

    NARCIS (Netherlands)

    E.B. Baart (Esther)

    2007-01-01

    textabstractThe introduction of this thesis provides the reader with the necessary background information to understand the rationale behind the studies conducted. It starts with the observation that human incidence of chromosomal abnormalities in oocytes and embryos. Furthermore, an explanation

  1. Effect of in vitro culture of human embryos on birthweight of newborns

    NARCIS (Netherlands)

    Dumoulin, John C.; Land, Jolande A.; Van Montfoort, Aafke P.; Nelissen, Ewka C.; Coonen, Edith; Derhaag, Josien G.; Schreurs, Inge L.; Dunselman, Gerard A.; Kester, Arnold D.; Geraedts, Joep P.; Evers, Johannes L.

    2010-01-01

    In animal models, in vitro culture of preimplantation embryos has been shown to be a risk factor for abnormal fetal outcome, including high and low birthweight. In the human, mean birthweight of singletons after in vitro fertilization (IVF) is considerably lower than after natural conception, but it

  2. A Chemical Probe that Labels Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Nao Hirata

    2014-03-01

    Full Text Available A small-molecule fluorescent probe specific for human pluripotent stem cells would serve as a useful tool for basic cell biology research and stem cell therapy. Screening of fluorescent chemical libraries with human induced pluripotent stem cells (iPSCs and subsequent evaluation of hit molecules identified a fluorescent compound (Kyoto probe 1 [KP-1] that selectively labels human pluripotent stem cells. Our analyses indicated that the selectivity results primarily from a distinct expression pattern of ABC transporters in human pluripotent stem cells and from the transporter selectivity of KP-1. Expression of ABCB1 (MDR1 and ABCG2 (BCRP, both of which cause the efflux of KP-1, is repressed in human pluripotent stem cells. Although KP-1, like other pluripotent markers, is not absolutely specific for pluripotent stem cells, the identified chemical probe may be used in conjunction with other reagents.

  3. Detection of teratogens in human serum using rat embryo culture: cancer and epilepsy treatments. [Detecting teratogenicity of anticonvulsant and antineoplastic drugs

    Energy Technology Data Exchange (ETDEWEB)

    Chatot, C. L.

    1979-01-01

    Growth (protein and DNA contents) of headfold stage rat embryos cultured for 48 hrs on human serum was enhanced by glucose supplementation. Embryo growth varied with the source of the serum. Sera from 3 of the 19 control subjects produced abnormal embryos. Sera from 5 subjects undergoing cancer chemotherapy and 6 subjects receiving anticonvulsants were either lethal or teratogenic to cultured rat embryos.

  4. Selective In Vitro Propagation of Nephron Progenitors Derived from Embryos and Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Shunsuke Tanigawa

    2016-04-01

    Full Text Available Nephron progenitors in the embryonic kidney propagate while generating differentiated nephrons. However, in mice, the progenitors terminally differentiate shortly after birth. Here, we report a method for selectively expanding nephron progenitors in vitro in an undifferentiated state. Combinatorial and concentration-dependent stimulation with LIF, FGF2/9, BMP7, and a WNT agonist is critical for expansion. The purified progenitors proliferated beyond the physiological limits observed in vivo, both for cell numbers and lifespan. Neonatal progenitors were maintained for a week, while progenitors from embryonic day 11.5 expanded 1,800-fold for nearly 20 days and still reconstituted 3D nephrons containing glomeruli and renal tubules. Furthermore, progenitors generated from mouse embryonic stem cells and human induced pluripotent cells could be expanded with retained nephron-forming potential. Thus, we have established in vitro conditions for promoting the propagation of nephron progenitors, which will be essential for dissecting the mechanisms of kidney organogenesis and for regenerative medicine.

  5. Microarray analysis of embryo-derived bovine pluripotent cells: The vulnerable state of bovine embryonic stem cells

    Science.gov (United States)

    Kim, Daehwan; Jung, Yeon-Gil

    2017-01-01

    Although there are many studies about pluripotent stem cells, little is known about pluripotent pathways and the difficulties of maintaining the pluripotency of bovine cells in vitro. Here, we investigated differently expressed genes (DEG) in bovine embryo-derived stem-like cells (eSLCs) from various origins to validate their distinct characteristics of pluripotency and differentiation. We identified core pluripotency markers and additional markers which were not determined as pluripotency markers yet in bovine eSLCs. Using the KEGG database, TGFβ, WNT, and LIF signaling were related to the maintenance of pluripotency. In contrast, some DEGs related to the LIF pathway were down-regulated, suggesting that reactivation of the pathway may be required for the establishment of true bovine embryonic stem cells (ESCs). Interestingly, oncogenes were co-down-regulated, while tumor suppressor genes were co-up-regulated in eSLCs, implying that this pattern may induce abnormal teratomas. These data analyses of signaling pathways provide essential information on authentic ESCs in addition to providing evidence for pluripotency in bovine eSLCs. PMID:28257460

  6. Stem Cells from Human Exfoliated Deciduous Tooth Exhibit Stromal-Derived Inducing Activity and Lead to Generation of Neural Crest Cells from Human Embryonic Stem Cells

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    Khadijeh Karbalaie

    2015-04-01

    Full Text Available Objective: The neural crest is a transient structure of early vertebrate embryos that generates neural crest cells (NCCs. These cells can migrate throughout the body and produce a diverse array of mature tissue types. Due to the ethical and technical problems surrounding the isolation of these early human embryo cells, researchers have focused on in vitro studies to produce NCCs and increase their knowledge of neural crest development. Materials and Methods: In this experimental study, we cultured human embryonic stem cells (hESCs on stromal stem cells from human exfoliated deciduous teeth (SHED for a two-week period. We used different approaches to characterize these differentiated cells as neural precursor cells (NPCs and NCCs. Results: In the first co-culture week, hESCs appeared as crater-like structures with marginal rosettes. NPCs derived from these structures expressed the early neural crest marker p75 in addition to numerous other genes associated with neural crest induction such as SNAIL, SLUG, PTX3 and SOX9. Flow cytometry analysis showed 70% of the cells were AP2/P75 positive. Moreover, the cells were able to self-renew, sustain multipotent differentiation potential, and readily form neurospheres in suspension culture. Conclusion: SHED, as an adult stem cell with a neural crest origin, has stromal-derived inducing activity (SDIA and can be used as an NCC inducer from hESCs. These cells provide an invaluable resource to study neural crest differentiation in both normal and disordered human neural crest development.

  7. Human serum teratogenicity studies using in vitro cultures of rat embryos

    Energy Technology Data Exchange (ETDEWEB)

    Klein, N.W.; Chatot, C.L.; Plenefisch, J.D.; Carey, S.W.

    1982-01-01

    Those conditions that constitute reproductive risks to man are being analyzed. Particular concern is with those conditions that cannot be or have not been identified by present methodologies. These conditions constitute the majority of factors causing fetal wastages and birth defects. The test system uses intact rat embryos that are cultured in vitro for 2 days. Findings to date suggest that this system may have a number of distinct advantages: (1) whole-embryo culture provides the test with the entire repertoire of processes involved in embryonic development; (2) whole-rat embryos can be cultured on high levels of blood serum; and (3) they can be cultured on serum from human subjects, which provides a direct and unique evaluation of the principal organism of concern. In regard to this last point, it is important to recognize that there is a large range of teratogenic responses and sensitivities to teratogens dependent upon both individual and species differences. (ERB)

  8. Extraction of DNA from human embryos after long-term preservation in formalin and Bouin's solutions.

    Science.gov (United States)

    Nagai, Momoko; Minegishi, Katsura; Komada, Munekazu; Tsuchiya, Maiko; Kameda, Tomomi; Yamada, Shigehito

    2016-05-01

    The "Kyoto Collection of Human Embryos" at Kyoto University was begun in 1961. Although morphological analyses of samples in the Kyoto Collection have been performed, these embryos have been considered difficult to genetically analyze because they have been preserved in formalin or Bouin's solution for 20-50 years. Owing to the recent advances in molecular biology, it has become possible to extract DNA from long-term fixed tissues. The purpose of this study was to extract DNA from wet preparations of human embryo samples after long-term preservation in fixing solution. We optimized the DNA extraction protocol to be suitable for tissues that have been damaged by long-term fixation, including DNA-protein crosslinking damage. Diluting Li2 CO3 with 70% ethanol effectively removed picric acid from samples fixed in Bouin's solution. Additionally, 20.0 mg/mL proteinase was valuable to lyse the long-term fixed samples. The extracted DNA was checked with PCR amplification using several sets of primers and sequence analysis. The PCR products included at least 295- and 838-bp amplicons. These results show that the extracted DNA is applicable for genetic analyses, and indicate that old embryos in the Kyoto Collection should be made available for future studies. The protocol described in this study can successfully extract DNA from old specimens and, with improvements, should be applicable in research aiming to understand the molecular mechanisms of human congenital anomalies. © 2015 Japanese Teratology Society.

  9. 胚胎体外培养及胚胎干细胞系的建立%In vitro culture of embryos and establishment of embryonic stem cell lines

    Institute of Scientific and Technical Information of China (English)

    王芳; 陈绍威

    2015-01-01

    BACKGROUND:The successful establishment of human embryonic stem cel lines in vitro is of great significance to human embryonic development mechanism and developmental biology, cel and tissue transplantation in the treatment of certain diseases. OBJECTIVE:To summarize the progress of in vitro culture of embryos and establishment of embryonic stem cel lines, to explore the influential factors for in vitro culture of embryos, and the methods of culturing human discarded embryos, isolating inner cel mass and establishing embryonic stem cel lines, as wel as the establishing conditions for embryonic stem cel lines. METHODS:With the key words of“embryo, embryonic stem cel s, coculture, sequential culture”, the first author searched CNKI and SCI databases for literatures concerning in vitro culture and transplantation of embryos and establishment of embryonic stem cel lines published from 2000 to 2014. Systematic evaluation was conducted. Final y, 58 literatures were retained for result analysis. RESULTS AND CONCLUSION:The culturing condition for embryos in vitro is the key factor affecting embryo transfer outcomes, including culture medium component and culture system. In previous studies, the component and application of culture medium have changed greatly, and the culture system has altered from single culture to coculture and sequential culture. Ethical issues and embryonic origin restrictions restrict the establishment of human embryonic stem cel lines. Clinical y discarded low-quality embryos can be used as one of the material sources to establish human embryonic stem cel lines, which can effectively lessen the problem of embryo shortage during the establishment of human embryonic stem cel lines and reduce ethical disputes.%背景:人类胚胎干细胞体外建系成功,对人类胚胎发育机制和发育生物学研究、细胞和组织移植治疗某些疾病等领域都有重大意义。目的:综述近年来关于胚胎体外

  10. Patents on inventions related to human embryonic stem cells: the morality clause after Brüstle v. Greenpeace.

    Science.gov (United States)

    Panis, Sarah

    2013-09-01

    This paper analyses the meaning of Article 6, para. 2, sub c of the Biotechnology Directive prohibiting patents on inventions using human embryos for industrial or commercial purposes. It first examines the evolution ofthe Court of Justice ofthe EU's interpretation of this provision (which is part of the morality clause) and focuses on its most recent decision, Brüstle v. Greenpeace. This is considered a landmark case for three reasons: firstly, because it defines for the first time the term "embryo" in patent law; secondly, because it is the Court of Justice (and not EPO) that ruled on patent law; the third reason is its very broad interpretation of the morality exclusion. The exclusion is no longer limited to embryos but is extended to (even banked) embryonic stem cells and all downstream products made with them. It then looks into the consequences for the patentability of inventions using cells derived from human embryonic stem cells, such as Brüstle's invention. The recent decision by Germany's Federal Court of Justice on the validity of Brüstle's patent emphasises the limited influence on the patentability of those inventions. After that, the paper addresses possible cuts in funding stem cell research and even legislative bans of this type of research. This is followed by an evaluation of the existence and content of the morality exclusion. After a comparative analysis with the US, which is lacking in such morality exclusion, the paper concludes that the morality clause as a whole paid its dues but the provision on the use of human embryos is questionable as there is no European consensus against the use of human embryos for industrial or commercial purposes.

  11. HIF1α is a regulator of hematopoietic progenitor and stem cell development in hypoxic sites of the mouse embryo

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    Parisa Imanirad

    2014-01-01

    Full Text Available Hypoxia affects many physiologic processes during early stages of mammalian ontogeny, particularly placental and vascular development. In the adult, the hypoxic bone marrow microenvironment plays a role in regulating hematopoietic stem cell (HSC function. HSCs are generated from the major vasculature of the embryo, but whether the hypoxic response affects the generation of these HSCs is as yet unknown. Here we examined whether Hypoxia Inducible Factor1-alpha (HIF1α, a key modulator of the response to hypoxia, is essential for HSC development. We found hypoxic cells in embryonic tissues that generate and expand hematopoietic cells (aorta, placenta and fetal liver, and specifically aortic endothelial and hematopoietic cluster cells. A Cre/loxP conditional knockout (cKO approach was taken to delete HIF1α in Vascular Endothelial-Cadherin expressing endothelial cells, the precursors to definitive hematopoietic cells. Functional assays show that HSC and hematopoietic progenitor cells (HPCs are significantly reduced in cKO aorta and placenta. Moreover, decreases in phenotypic aortic hematopoietic cluster cells in cKO embryos indicate that HIF1α is necessary for generation and/or expansion of HPCs and HSCs. cKO adult BM HSCs are also affected under transplantation conditions. Thus, HIF1α is a regulator of HSC generation and function beginning at the earliest embryonic stages.

  12. Energy metabolism in human pluripotent stem cells and their differentiated counterparts.

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    Sandra Varum

    Full Text Available Human pluripotent stem cells have the ability to generate all cell types present in the adult organism, therefore harboring great potential for the in vitro study of differentiation and for the development of cell-based therapies. Nonetheless their use may prove challenging as incomplete differentiation of these cells might lead to tumoregenicity. Interestingly, many cancer types have been reported to display metabolic modifications with features that might be similar to stem cells. Understanding the metabolic properties of human pluripotent stem cells when compared to their differentiated counterparts can thus be of crucial importance. Furthermore recent data has stressed distinct features of different human pluripotent cells lines, namely when comparing embryo-derived human embryonic stem cells (hESCs and induced pluripotent stem cells (IPSCs reprogrammed from somatic cells.We compared the energy metabolism of hESCs, IPSCs, and their somatic counterparts. Focusing on mitochondria, we tracked organelle localization and morphology. Furthermore we performed gene expression analysis of several pathways related to the glucose metabolism, including glycolysis, the pentose phosphate pathway and the tricarboxylic acid (TCA cycle. In addition we determined oxygen consumption rates (OCR using a metabolic extracellular flux analyzer, as well as total intracellular ATP levels by high performance liquid chromatography (HPLC. Finally we explored the expression of key proteins involved in the regulation of glucose metabolism.Our results demonstrate that, although the metabolic signature of IPSCs is not identical to that of hESCs, nonetheless they cluster with hESCs rather than with their somatic counterparts. ATP levels, lactate production and OCR revealed that human pluripotent cells rely mostly on glycolysis to meet their energy demands. Furthermore, our work points to some of the strategies which human pluripotent stem cells may use to maintain high

  13. Derivation of the clinical grade human embryonic stem cell line RCe016-A (RC-12

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    P.A. De Sousa

    2016-05-01

    Full Text Available The human embryonic stem cell line RCe016-A (RC-12 was derived under quality assured compliance with UK regulations, EU Directives and International guidance for tissue procurement, processing and storage according to good manufacturing practice (GMP standards. The cell line was derived from a cryopreserved blastocyst stage embryo voluntarily donated as surplus to fertility requirements following informed consent. RCe016-A (RC-12 shows normal pluripotency marker expression and differentiation to three germ layers in vitro. Karyology revealed a mixed male karyotype at early passage (P15, which resolved as normal 46XY by passage 33. Microsatellite PCR identity, HLA and blood group typing data is available.

  14. Derivation of the clinical grade human embryonic stem cell line RCe019-A (RC-15

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    P.A. De Sousa

    2016-05-01

    Full Text Available The human embryonic stem cell line RCe019-A (RC-15 was derived under quality assured compliance with UK regulation, European Union Directives and International guidance for tissue procurement, processing and storage according to Good Manufacturing Practice (GMP standards. The cell line was derived from a cleavage stage embryo voluntarily donated as unsuitable or surplus to fertility requirements following informed consent. RCe019-A (RC-15 shows normal pluripotency marker expression and differentiation to the three germ layers in vitro. It has a mixed 46XX/47XX, +8 female karyotype and microsatellite PCR identity, HLA and blood group typing data is available.

  15. Derivation of the clinical grade human embryonic stem cell line RCe015-A (RC-11

    Directory of Open Access Journals (Sweden)

    P.A. De Sousa

    2016-07-01

    Full Text Available The human embryonic stem cell line RCe015-A (RC-11 was derived under quality assured compliance with UK regulation, European Union Directives and International guidance for tissue procurement, processing and storage according to Good Manufacturing Practice (GMP standards. The cell line was derived from a fragmented cleavage stage embryo voluntarily donated as unsuitable or surplus to fertility requirements following informed consent. RCe015-A (RC-11 shows normal pluripotency marker expression and differentiation to the three germ layers in vitro and in vivo. It has a normal 46XX female karyotype and microsatellite PCR identity, HLA and blood group typing data are available.

  16. Derivation of the clinical grade human embryonic stem cell line RCe021-A (RC-17

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    P.A. De Sousa

    2016-07-01

    Full Text Available The human embryonic stem cell line RCe021-A (RC-17 was derived under quality assured compliance with UK regulation, European Union Directives and International guidance for tissue procurement, processing and storage according to Good Manufacturing Practice (GMP standards. The cell line was derived from a day 3 embryo voluntarily donated as unsuitable or surplus to fertility requirements following informed consent. RCe021-A (RC-17 shows normal pluripotency marker expression and differentiation to the three germ layers in vitro. It has a normal 46XX female karyotype and microsatellite PCR identity, HLA and blood group typing data are available.

  17. Human parthenogenetic embryonic stem cells:one potential resource for cell therapy

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Pluripotent stem cells derived from somatic cells through such processes as nuclear transfer or induced pluripotent stem(iPS) cells present an important model for biomedical research and provide potential resources for cell replacement therapies.However,the overall efficiency of the conversional nuclear transfer is very low and the safety issue remains a major concern for iPS cells.Embryonic stem cells(ESCs) generated from parthenogenetic embryos are one attractive alternative as a source of histocompatible cells and tissues for cell therapy.Recent studies on human parthenogenetic embryonic stem cells(hPG ESCs) have revealed that these ESCs are very similar to the hESCs derived from IVF or in vivo produced blastocysts in gene expression and other characteristics,but full differentiation and development potential of these hPG ESCs have to be further investigated before clinical research and therapeutic interventions.To generate various pluripotent stem cells,diverse reprogramming techniques and approaches will be developed and integrated.This may help elucidate the fundamental mechanisms underlying reprogramming and stem cell biology,and ultimately benefit cell therapy and regenerative medicine.

  18. Human parthenogenetic embryonic stem cells: one potential resource for cell therapy

    Institute of Scientific and Technical Information of China (English)

    HAO Jie; HU WanWan; SHENG Chao; YU Yang; ZHOU Qi

    2009-01-01

    Pluripotent stem cells derived from somatic cells through such processes as nuclear transfer or in duced pluripotent stem (iPS) cells present an important model for biomedical research and provide potential resources for cell replacement therapies. However, the overall efficiency of the conversional nuclear transfer is very low and the safety issue remains a major concern for iPS cells. Embryonic stem cells (ESCs) generated from parthenogenetic embryos are one attractive alternative as a source of histocompatible cells and tissues for cell therapy. Recent studies on human parthenogenetic embryonic stem cells (hPG ESCs) have revealed that these ESCs are very similar to the hESCs derived from IVF or in vivo produced blastocysts in gene expression and other characteristics, but full differentiation and development potential of these hPG ESCs have to be further investigated before clinical research and therapeutic interventions. To generate various pluripotent stem cells, diverse reprogramming techniques and approaches will be developed and integrated. This may help elucidate the fundamental mechanisms underlying reprogramming and stem cell biology, and ultimately benefit cell therapy and regenerative medicine.

  19. Development and specification of cerebellar stem and progenitor cells in zebrafish: from embryo to adult

    OpenAIRE

    Kaslin, Jan; Kroehne, Volker; Benato, Francesca; Argenton, Francesco; Brand, Michael

    2013-01-01

    Background Teleost fish display widespread post-embryonic neurogenesis originating from many different proliferative niches that are distributed along the brain axis. During the development of the central nervous system (CNS) different cell types are produced in a strict temporal order from increasingly committed progenitors. However, it is not known whether diverse neural stem and progenitor cell types with restricted potential or stem cells with broad potential are maintained in the teleost...

  20. Development and specification of cerebellar stem and progenitor cells in zebrafish: from embryo to adult

    OpenAIRE

    Kaslin, Jan; Kroehne, Volker; Benato, Francesca; Argenton, Francesco; Brand, Michael

    2013-01-01

    Background Teleost fish display widespread post-embryonic neurogenesis originating from many different proliferative niches that are distributed along the brain axis. During the development of the central nervous system (CNS) different cell types are produced in a strict temporal order from increasingly committed progenitors. However, it is not known whether diverse neural stem and progenitor cell types with restricted potential or stem cells with broad potential are maintained in the teleost...

  1. [Human pluripotent stem cell and neural differentiation].

    Science.gov (United States)

    Wataya, Takafumi; Muguruma, Keiko; Sasai, Yoshiki

    2008-10-01

    Recovery of lost brain function is an important issue in medical studies because neurons of the central nervous system (CNS) have poor potential for regeneration. Since few CNS diseases can be treated completely by medicines, regenerative therapy by using stem cells should be studied as a new type of therapeutic intervention. The efficacy of cell replacement therapy in Parkinson's disease has been well investigated. Several studies on fetal tissue transplantation have revealed that quantity and purity of transplanted cells are necessary for recovery of symptoms. SFEB (Serum-free floating culture of embryoid body-like aggregates) method is capable of inducing multi-potential CNS progenitors that can be steered to differentiate into region-specific tissues. On the basis of the existing knowledge of embryology, we have succeeded in the generating of various types of neurons such as telencephalic, cerebeller (Purkinje and granule cells), retinal (photoreceptor cells) and hypothalamic neurons. Application of this culture method to human ES (hES) cells is necessary for clinical purpose: however, poor survival of hES cells in SFEB culture might limit the possibility of using these cells for future medical applications. We found that a selective Rho-associated kinase (ROCK) inhibitor, Y-27632, markedly diminished the dissociation-induced apoptosis of hES cells and enabled the cells to form aggregates in SFEB culture. For both mouse and human ES cells, SFEB culture is a favorable method that can generate large amounts of region-specific neurons. However, stem cell-based therapy continues to face several obstacles. It is important that researchers in the basic sciences and clinical medicine should discuss these problems together to overcome both scientific and ethical issues related to stem cells.

  2. The Effect of Prolonged Culture of Chromosomally Abnormal Human Embryos on The Rate of Diploid Cells

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    Masood Bazrgar

    2016-12-01

    Full Text Available Background: A decrease in aneuploidy rate following a prolonged co-culture of human blastocysts has been reported. As co-culture is not routinely used in assisted reproductive technology, the present study aimed to evaluate the effect of the prolonged single culture on the rate of diploid cells in human embryos with aneuploidies. Materials and Methods: In this cohort study, we used fluorescence in situ hybridization (FISH to reanalyze surplus blastocysts undergoing preimplantation genetic diagnosis (PGD on day 3 postfertilization. They were randomly studied on days 6 or 7 following fertilization. Results: Of the 30 analyzed blastocysts, mosaicism was observed in 26(86.6%, while 2(6.7% were diploid, and 2(6.7% were triploid. Of those with mosaicism, 23(88.5% were determined to be diploid-aneuploid and 3(11.5% were aneuploid mosaic. The total frequency of embryos with more than 50% diploid cells was 33.3% that was lower on day 7 in comparison with the related value on day 6 (P<0.05; however, there were no differences when the embryos were classified according to maternal age, blastocyst developmental stage, total cell number on day 3, and embryo quality. Conclusion: Although mosaicism is frequently observed in blastocysts, the prolonged single culture of blastocysts does not seem to increase the rate of normal cells.

  3. Time-lapse cinematography of dynamic changes occurring during in vitro development of human embryos.

    Science.gov (United States)

    Mio, Yasuyuki; Maeda, Kazuo

    2008-12-01

    The purpose of this study was to clarify developmental changes of early human embryos by using time-lapse cinematography (TLC). For human ova, fertilization and cleavage, development of the blastocyst, and hatching, as well as consequent changes were repeatedly photographed at intervals of 5-6 days by using an inverse microscope under stabilized temperature and pH. Photographs were taken at 30 frames per second and the movies were studied. Cinematography has increased our understanding of the morphologic mechanisms of fertilization, development, and behavior of early human embryos, and has identified the increased risk of monozygotic twin pregnancy based on prolonged incubation in vitro to the blastocyst stage. Using TLC, we observed the fertilization of an ovum by a single spermatozoon, followed by early cleavages, formation of the morula, blastocyst hatching, changes in the embryonic plates, and the development of monozygotic twins from the incubated blastocysts.

  4. Genetic Manipulation of Human Embryonic Stem Cells.

    Science.gov (United States)

    Eiges, Rachel

    2016-01-01

    One of the great advantages of embryonic stem (ES) cells over other cell types is their accessibility to genetic manipulation. They can easily undergo genetic modifications while remaining pluripotent, and can be selectively propagated, allowing the clonal expansion of genetically altered cells in culture. Since the first isolation of ES cells in mice, many effective techniques have been developed for gene delivery and manipulation of ES cells. These include transfection, electroporation, and infection protocols, as well as different approaches for inserting, deleting, or changing the expression of genes. These methods proved to be extremely useful in mouse ES cells, for monitoring and directing differentiation, discovering unknown genes, and studying their function, and are now being extensively implemented in human ES cells (HESCs). This chapter describes the different approaches and methodologies that have been applied for the genetic manipulation of HESCs and their applications. Detailed protocols for generating clones of genetically modified HESCs by transfection, electroporation, and infection will be described, with special emphasis on the important technical details that are required for this purpose. All protocols are equally effective in human-induced pluripotent stem (iPS) cells.

  5. Genome editing: a robust technology for human stem cells.

    Science.gov (United States)

    Chandrasekaran, Arun Pandian; Song, Minjung; Ramakrishna, Suresh

    2017-09-01

    Human pluripotent stem cells comprise induced pluripotent and embryonic stem cells, which have tremendous potential for biological and therapeutic applications. The development of efficient technologies for the targeted genome alteration of stem cells in disease models is a prerequisite for utilizing stem cells to their full potential. Genome editing of stem cells is possible with the help of synthetic nucleases that facilitate site-specific modification of a gene of interest. Recent advances in genome editing techniques have improved the efficiency and speed of the development of stem cells for human disease models. Zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system are powerful tools for editing DNA at specific loci. Here, we discuss recent technological advances in genome editing with site-specific nucleases in human stem cells.

  6. Isolation and characterization of human spermatogonial stem cells

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    Liu Shixue

    2011-10-01

    Full Text Available Abstract Background To isolate and characterization of human spermatogonial stem cells from stem spermatogonium. Methods The disassociation of spermatogonial stem cells (SSCs were performed using enzymatic digestion of type I collagenase and trypsin. The SSCs were isolated by using Percoll density gradient centrifugation, followed by differential surface-attachment method. Octamer-4(OCT4-positive SSC cells were further identified using immunofluorescence staining and flow cytometry technques. The purity of the human SSCs was also determined, and a co-culture system for SSCs and Sertoli cells was established. Results The cell viability was 91.07% for the suspension of human spermatogonial stem cells dissociated using a two-step enzymatic digestion process. The cells isolated from Percoll density gradient coupled with differential surface-attachement purification were OCT4 positive, indicating the cells were human spermatogonial stem cells. The purity of isolated human spermatogonial stem cells was 86.7% as assessed by flow cytometry. The isolated SSCs were shown to form stable human spermatogonial stem cell colonies on the feeder layer of the Sertoli cells. Conclusions The two-step enzyme digestion (by type I collagenase and trypsin process is an economical, simple and reproducible technique for isolating human spermatogonial stem cells. With little contamination and less cell damage, this method facilitates isolated human spermatogonial stem cells to form a stable cell colony on the supporting cell layer.

  7. Equivalency of buffalo (Bubalus bubalis) embryonic stem cells derived from fertilized, parthenogenetic, and hand-made cloned embryos.

    Science.gov (United States)

    Muzaffar, Musharifa; Selokar, Naresh L; Singh, Karn P; Zandi, Mohammad; Singh, Manoj K; Shah, Riaz A; Chauhan, Manmohan S; Singla, Suresh K; Palta, Prabhat; Manik, Radheysham

    2012-06-01

    This study was aimed at establishing buffalo embryonic stem cells (ESCs) from in vitro fertilized (IVF), parthenogenetic, and hand-made cloned (HMC) embryos and to check their equivalency in terms of stem cell marker expression, longevity, proliferation, and differentiation pattern. ESCs derived from all three sources were found by immunofluorescence to express the pluripotency markers SSEA-4, TRA-1-60, TRA-1-81, OCT4, and SOX2 and were able to form embryoid bodies containing cells expressing genes specific to endoderm (AFP, HNF4, and GATA4), mesoderm (MSX1, BMP4, and ASA), and ectoderm (cytokeratin 8 and NF68). Reverse transcriptase PCR (RT-PCR) showed cells from all sources to be positive for pluripotency markers OCT4, SOX2, NANOG, STAT3, REX1, FOXD3, NUCLEOSTEMIN, and TELOMERASE. Pluripotency markers OCT4, SOX2, NANOG, and c-MYC were also analyzed by real-time PCR. No significant differences were observed among ESCs from all three sources for all these genes except NANOG, whose expression was higher (pcloning, chimera formation, and transgenic animal production.

  8. MicroRNAs: From Female Fertility, Germ Cells, and Stem Cells to Cancer in Humans

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    Irma Virant-Klun

    2016-01-01

    Full Text Available MicroRNAs are a family of naturally occurring small noncoding RNA molecules that play an important regulatory role in gene expression. They are suggested to regulate a large proportion of protein encoding genes by mediating the translational suppression and posttranscriptional control of gene expression. Recent findings show that microRNAs are emerging as important regulators of cellular differentiation and dedifferentiation, and are deeply involved in developmental processes including human preimplantation development. They keep a balance between pluripotency and differentiation in the embryo and embryonic stem cells. Moreover, it became evident that dysregulation of microRNA expression may play a fundamental role in progression and dissemination of different cancers including ovarian cancer. The interest is still increased by the discovery of exosomes, that is, cell-derived vesicles, which can carry different proteins but also microRNAs between different cells and are involved in cell-to-cell communication. MicroRNAs, together with exosomes, have a great potential to be used for prognosis, therapy, and biomarkers of different diseases including infertility. The aim of this review paper is to summarize the existent knowledge on microRNAs related to female fertility and cancer: from primordial germ cells and ovarian function, germinal stem cells, oocytes, and embryos to embryonic stem cells.

  9. Contested embryonic culture in Japan--public discussion, and human embryonic stem cell research in an aging welfare society.

    Science.gov (United States)

    Sleeboom-Faulkner, Margaret

    2010-01-01

    This article explores the reasons for the lack of a broad discussion on bioethical regulation of human embryonic stem cell research (hESR) in Japan and asks why scientists experience difficulties accessing resources for hESR despite the acclaimed indifference of dominant Japanese culture to embryo research. The article shows how various social actors express their views on the embryo and oocyte donation in terms of dominant Japanese culture, foiled against what is regarded as Western culture. Second, it shows how the lack of concern with hESR should be understood in the context of public health policies and communications and bioethics decision making in Japan. Finally, it interprets the meaning of the embryo in the context of Japan as an aging modern welfare society, explaining how policymakers have come to emphasize the urgency of infertility problems over issues around abortion and embryonic life.

  10. In the world of Dolly, when does a human embryo acquire respect?

    Science.gov (United States)

    Cameron, C; Williamson, R

    2005-04-01

    For most of the 20th century, it was possible to regard fertilisation as the identifiable point when life begins, because this moment could be defined unequivocally and was thought to be the single most essential biological step in the establishment of a new human entity. Since the successful reproductive cloning of Dolly and other mammals, it is clear that any human cell has the potential to supply the full genome of an embryo, and hence a person, without going through fertilisation. At what point in time do such embryos acquire the respect accorded to human beings? The authors argue that the time of implantation is the most useful point at which the potential and the intention to create a new person are translated into reality, because from that point a new life develops. Implantation differentiates a somatic cell in culture (which is not due respect) from a human entity that has acquired its own identity and developmental potential. The authors examine the value of quickening or viability as alternative developmental stages in the process of acquiring respect for the Dolly embryo.

  11. Evaluation of the rat embryo culture system as a predictive test for human teratogens.

    Science.gov (United States)

    Guest, I; Buttar, H S; Smith, S; Varma, D R

    1994-01-01

    Ingestion of the anticonvulsant drug valproic acid and of the angiotensin converting enzyme inhibitor captopril during pregnancy has been associated with abnormal fetal outcome in humans. In contrast, the use of the antiinflammatory drug ibuprofen and the antihistamine diphenhydramine has not been documented to be embryotoxic in humans. We evaluated the rat embryo culture system as a predictive model of teratogenesis, using these four drugs as test agents. Valproic acid, ibuprofen, and diphenhydramine were embryotoxic, inducing concentration-dependent decreases in growth and a significant increase in anomalies. Valproic acid caused an increase in neural tube defects, ibuprofen increased the incidence of abnormal maxillary processes, and diphenhydramine increased the number of embryos with distorted body morphology. These abnormalities were induced at concentrations of valproic acid and diphenhydramine that are used clinically, but ibuprofen only induced toxicity at concentrations greatly exceeding the therapeutic range. Captopril was not embryotoxic up to 5 mM, the highest concentration tested. These results suggest that the rat embryo culture system produces both false positive and false negative data on the teratogenic potential of drugs. Although such an in vitro assay may be suitable to determine the mechanism of teratogenesis, it is not a sensitive indicator of potential human teratogens on its own. These data support the view that in vitro systems can only supplement clinical and epidemiological observations in humans, possibly as a method to determine mechanisms of actions of teratogens.

  12. Generation of human induced pluripotent stem cells from dermal fibroblasts

    OpenAIRE

    2008-01-01

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ...

  13. Effect of Adding Human Chorionic Gonadotropin to The Endometrial Preparation Protocol in Frozen Embryo Transfer Cycles

    Directory of Open Access Journals (Sweden)

    Maryam Eftekhar

    2012-01-01

    Full Text Available Background: Human chorionic gonadotropin (HCG, one of the initial embryonic signals, isprobably a major regulator of the embryo-endometrial relationship. This study aims to assess theadvantage of HCG supplementation during the secretory phase of hormonally prepared cycles forthe transfer of cryopreserved-thawed embryos.Materials and Methods: This study was a randomized clinical trial. Infertile women who werecandidates for frozen-thawed embryo transfers entered the study and were divided into two groups,HCG and control. The endometrial preparation method was similar in both groups: all women receivedestradiol valerate (6 mg po per day from the second day of the menstrual cycle and progesteronein oil (100 mg intramuscular (I.M. when the endometrial thickness reached 8 mm. Estradiol andprogesterone were continued until the tenth week of gestation. In the HCG group, patients received anHCG 5000 IU injection on the first day of progesterone administration and the day of embryo transfer.Results: In this study, 130 couples participated: 65 in the HCG group and 65 in the control group.There was no statistically significant difference between groups regarding basic characteristics.Implantation rate, chemical pregnancy, clinical pregnancy, ongoing pregnancy, and abortion rateswere similar in both groups.Conclusion: Although HCG has some advantages in assisted reproductive technology (ARTcycles, our study did not show any benefit of HCG supplementation during the secretory phase offrozen cycles (Registration Number: IRCT201107266420N4.

  14. Differences in the microrheology of human embryonic stem cells and human induced pluripotent stem cells.

    Science.gov (United States)

    Daniels, Brian R; Hale, Christopher M; Khatau, Shyam B; Kusuma, Sravanti; Dobrowsky, Terrence M; Gerecht, Sharon; Wirtz, Denis

    2010-12-01

    Embryonic and adult fibroblasts can be returned to pluripotency by the expression of reprogramming genes. Multiple lines of evidence suggest that these human induced pluripotent stem (hiPS) cells and human embryonic stem (hES) cells are behaviorally, karyotypically, and morphologically similar. Here we sought to determine whether the physical properties of hiPS cells, including their micromechanical properties, are different from those of hES cells. To this end, we use the method of particle tracking microrheology to compare the viscoelastic properties of the cytoplasm of hES cells, hiPS cells, and the terminally differentiated parental human fibroblasts from which our hiPS cells are derived. Our results indicate that although the cytoplasm of parental fibroblasts is both viscous and elastic, the cytoplasm of hiPS cells does not exhibit any measurable elasticity and is purely viscous over a wide range of timescales. The viscous phenotype of hiPS cells is recapitulated in parental cells with disassembled actin filament network. The cytoplasm of hES cells is predominantly viscous but contains subcellular regions that are also elastic. This study supports the hypothesis that intracellular elasticity correlates with the degree of cellular differentiation and reveals significant differences in the mechanical properties of hiPS cells and hES cells. Because mechanical stimuli have been shown to mediate the precise fate of differentiating stem cells, our results support the concept that stem cell "softness" is a key feature of force-mediated differentiation of stem cells and suggest there may be subtle functional differences between force-mediated differentiation of hiPS cells and hES cells.

  15. Biological impact of human embryonic stem cells.

    Science.gov (United States)

    Martín, Miguel; Menéndez, Pablo

    2012-01-01

    Research on human embryonic stem cells (hESCs) and induced pluripotent (iPS) stem cells is currently a field of great potential in biomedicine. These cells represent a highly valuable tool for developmental biology studies, disease models, and drug screening and toxicity. The ultimate goal of hESCs and iPS cell research is the treatment of diseases or disorders for which there is currently no treatment or existing therapies are only partially effective. Despite the disproportionate short-term hopes generated, which are putting too much pressure on scientists, the international scientific community is making rapid progress in understanding hESCs and iPS cells. Nonetheless, great efforts have to be made to provide an answer to still quite basic questions concerning their biology. Moreover, translation to clinical applications in cell replacement therapy requires prior solution to ethical barriers. The recent development of iPS cells has provided a strong alternative to overcome ethical issues concerning hESCs. However, an in-depth characterization of their genetic and epigenetic features, as well as their differentiation potential still remains to be undertaken. This chapter will describe, precisely, what the critical issues are, where scientific and ethical barriers stand, and how we are to overcome them. Only then, we shall finally discover whether hESCs and iPS cells will allow building reproducible disease models, and whether they really are a safe tool, with great potential for regenerative medicine.

  16. Human tissue legislation in South Africa: Focus on stem cell ...

    African Journals Online (AJOL)

    Human tissue legislation in South Africa: Focus on stem cell research and therapy. ... Related Substances Act, the Consumer Protection Act, the Children's Act and ... human tissue legislation in SA, the legislator has an opportunity to mirror the ...

  17. Human embryonic stem cells: preclinical perspectives

    Directory of Open Access Journals (Sweden)

    Sarda Kanchan

    2008-01-01

    Full Text Available Abstract Human embryonic stem cells (hESCs have been extensively discussed in public and scientific communities for their potential in treating diseases and injuries. However, not much has been achieved in turning them into safe therapeutic agents. The hurdles in transforming hESCs to therapies start right with the way these cells are derived and maintained in the laboratory, and goes up-to clinical complications related to need for patient specific cell lines, gender specific aspects, age of the cells, and several post transplantation uncertainties. The different types of cells derived through directed differentiation of hESC and used successfully in animal disease and injury models are described briefly. This review gives a brief outlook on the present and the future of hESC based therapies, and talks about the technological advances required for a safe transition from laboratory to clinic.

  18. Cell-free DNA in human follicular fluid as a biomarker of embryo quality.

    Science.gov (United States)

    Scalici, E; Traver, S; Molinari, N; Mullet, T; Monforte, M; Vintejoux, E; Hamamah, S

    2014-12-01

    Could cell-free DNA (cfDNA) quantification in individual human follicular fluid (FF) samples become a new non-invasive predictive biomarker for in vitro fertilization (IVF) outcomes? CfDNA level in human follicular fluid samples was significantly correlated with embryo quality and could be used as an innovative non-invasive biomarker to improve IVF outcomes. CfDNA fragments, resulting from apoptotic or necrotic events, are present in the bloodstream and their quantification is already used as a biomarker for gynaecological and pregnancy disorders. Follicular fluid is important for oocyte development and contains plasma components and factors secreted by granulosa cells during folliculogenesis. CfDNA presence in follicular fluid and its potential use as an IVF outcome biomarker have never been investigated. One hundred individual follicular fluid samples were collected from 43 female patients undergoing conventional IVF (n = 26) or ICSI (n = 17). CfDNA level was quantified in each individual follicular fluid sample. At oocyte collection day, follicles were aspirated individually. Only blood-free follicular fluid samples were included in the study. Follicle size was calculated based on the follicular fluid volume. Each corresponding cumulus-oocyte complex was isolated for IVF or ICSI procedures. Follicular fluid cfDNA was measured by quantitative PCR with ALU-specific primers. Human follicular fluid samples from individual follicles contain measurable amounts of cfDNA (mean ± SD, 1.62 ± 2.08 ng/µl). CfDNA level was significantly higher in small follicles (8-12 mm in diameter) than in large ones (>18 mm) (mean ± SD, 2.54 ± 0.78 ng/µl versus 0.71 ± 0.44 ng/µl, respectively, P = 0.007). Moreover, cfDNA concentration was significantly and negatively correlated with follicle size (r = -0.34; P = 0.003). A weak significant negative correlation between DNA integrity and 17β-estradiol level in follicular fluid samples at oocyte collection day was observed (r = -0

  19. Jewish points of views on the animation of the human embryo

    Directory of Open Access Journals (Sweden)

    Ks. Artur Aleksiejuk

    2014-11-01

    Full Text Available According to biblical anthropology, human beings are composed of body and soul. The question arises, however, at what moment does the body of the embryo possess a spiritual element? Can the breath of God visit the created and already developing in its own biological rhythm embryo? The key issue here is the moment of animation – the origin of a living being, which is created in the image and likeness of God. This article presents various Jewish points of views on the animation of the human embryo, all of which attempt to determine the exact moment at which the soul is breathed into the human body. Rabbinical authorities distinguish five different moments in this process: conception, the forty first day after conception, the birth of the child, the moment of circumcision and the moment in which the child is able to say “Amen.” The first three mentioned cases have the most supporters. The first refers to the simultaneous animation, while the other theories argue for successive animation.

  20. Transcriptional analysis of early lineage commitment in human embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Wormald Sam

    2007-03-01

    Full Text Available Abstract Background The mechanisms responsible for the maintenance of pluripotency in human embryonic stem cells, and those that drive their commitment into particular differentiation lineages, are poorly understood. In fact, even our knowledge of the phenotype of hESC is limited, because the immunological and molecular criteria presently used to define this phenotype describe the properties of a heterogeneous population of cells. Results We used a novel approach combining immunological and transcriptional analysis (immunotranscriptional profiling to compare gene expression in hESC populations at very early stages of differentiation. Immunotranscriptional profiling enabled us to identify novel markers of stem cells and their differentiated progeny, as well as novel potential regulators of hESC commitment and differentiation. The data show clearly that genes associated with the pluripotent state are downregulated in a coordinated fashion, and that they are co-expressed with lineage specific transcription factors in a continuum during the early stages of stem cell differentiation. Conclusion These findings, that show that maintenance of pluripotency and lineage commitment are dynamic, interactive processes in hESC cultures, have important practical implications for propagation and directed differentiation of these cells, and for the interpretation of mechanistic studies of hESC renewal and commitment. Since embryonic stem cells at defined stages of commitment can be isolated in large numbers by immunological means, they provide a powerful model for studying molecular genetics of stem cell commitment in the embryo.

  1. Transcriptional analysis of early lineage commitment in human embryonic stem cells

    Science.gov (United States)

    Laslett, Andrew L; Grimmond, Sean; Gardiner, Brooke; Stamp, Lincon; Lin, Adelia; Hawes, Susan M; Wormald, Sam; Nikolic-Paterson, David; Haylock, David; Pera, Martin F

    2007-01-01

    Background The mechanisms responsible for the maintenance of pluripotency in human embryonic stem cells, and those that drive their commitment into particular differentiation lineages, are poorly understood. In fact, even our knowledge of the phenotype of hESC is limited, because the immunological and molecular criteria presently used to define this phenotype describe the properties of a heterogeneous population of cells. Results We used a novel approach combining immunological and transcriptional analysis (immunotranscriptional profiling) to compare gene expression in hESC populations at very early stages of differentiation. Immunotranscriptional profiling enabled us to identify novel markers of stem cells and their differentiated progeny, as well as novel potential regulators of hESC commitment and differentiation. The data show clearly that genes associated with the pluripotent state are downregulated in a coordinated fashion, and that they are co-expressed with lineage specific transcription factors in a continuum during the early stages of stem cell differentiation. Conclusion These findings, that show that maintenance of pluripotency and lineage commitment are dynamic, interactive processes in hESC cultures, have important practical implications for propagation and directed differentiation of these cells, and for the interpretation of mechanistic studies of hESC renewal and commitment. Since embryonic stem cells at defined stages of commitment can be isolated in large numbers by immunological means, they provide a powerful model for studying molecular genetics of stem cell commitment in the embryo. PMID:17335568

  2. The production and directed differentiation of human embryonic stem cells.

    Science.gov (United States)

    Trounson, Alan

    2006-04-01

    Human embryonic stem cells (hESCs) are being rapidly produced from chromosomally euploid, aneuploid, and mutant human embryos that are available from in vitro fertilization clinics treating patients for infertility or preimplantation genetic diagnosis. These hESC lines are an important resource for functional genomics, drug screening, and, perhaps eventually, cell and gene therapy. The methods for deriving hESCs are well established and repeatable and are relatively successful with a ratio of 1:10 to 1:2 new hESC lines produced from 4- to 8-d-old morula and blastocysts and from isolated inner cell mass cell clusters of human blastocysts. The hESCs can be formed and maintained on human somatic cells in humanized serum-free culture conditions and for several passages in cell-free culture systems. The hESCs can be transfected with DNA constructs. Their gene expression profiles are being described and immunological characteristics determined. They may be grown indefinitely in vitro while maintaining their original karyotype and epigenetic status, but this needs to be confirmed from time to time in long-term cultures. hESCs spontaneously differentiate in the absence of the appropriate cell feeder layer, when overgrown in culture and when isolated from the ESC colony. All three major embryonic lineages are produced in differentiating flat attachment cultures and unattached embryoid bodies. Cell progenitors of interest can be identified by markers, expression of reporter genes, and characteristic morphology, and the cells thereafter enriched for progenitor types and further culture to more mature cell types. Directed differentiation systems are well developed for ectodermal pathways that result in neural and glial cells and the mesendodermal pathway for cardiac muscle cells and many other cell types including hematopoietic progenitors and endothelial cells. Directed differentiation into endoderm has been more difficult to achieve, perhaps because of the lack of markers of

  3. Generation of chimeras by aggregation of embryonic stem cells with diploid or tetraploid mouse embryos.

    Science.gov (United States)

    Artus, Jérôme; Hadjantonakis, Anna-Katerina

    2011-01-01

    From the hybrid creatures of the Greek and Egyptian mythologies, the concept of the chimera has evolved and, in modern day biology, refers to an organism comprises of at least two populations of genetically distinct cells. Mouse chimeras have proven an invaluable tool for the generation of genetically modified strains. In addition, chimeras have been extensively used in developmental biology as a powerful tool to analyze the phenotype of specific mutations, to attribute function to gene products and to address the question of cell autonomy versus noncell autonomy of gene function. This chapter describes a simple and economical technique used to generate mouse chimeras by embryo aggregation. Multiple aggregation combinations are described each of which can be tailored to answer particular biological questions.

  4. Human umbilical cord mesenchymal stem cells: a new era for stem cell therapy.

    Science.gov (United States)

    Ding, Dah-Ching; Chang, Yu-Hsun; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2015-01-01

    The human umbilical cord is a promising source of mesenchymal stem cells (HUCMSCs). Unlike bone marrow stem cells, HUCMSCs have a painless collection procedure and faster self-renewal properties. Different derivation protocols may provide different amounts and populations of stem cells. Stem cell populations have also been reported in other compartments of the umbilical cord, such as the cord lining, perivascular tissue, and Wharton's jelly. HUCMSCs are noncontroversial sources compared to embryonic stem cells. They can differentiate into the three germ layers that promote tissue repair and modulate immune responses and anticancer properties. Thus, they are attractive autologous or allogenic agents for the treatment of malignant and nonmalignant solid and soft cancers. HUCMCs also can be the feeder layer for embryonic stem cells or other pluripotent stem cells. Regarding their therapeutic value, storage banking system and protocols should be established immediately. This review critically evaluates their therapeutic value, challenges, and future directions for their clinical applications.

  5. Estimating limits for natural human embryo mortality [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Gavin E. Jarvis

    2016-12-01

    Full Text Available Natural human embryonic mortality is generally considered to be high. Values of 70% and higher are widely cited. However, it is difficult to determine accurately owing to an absence of direct data quantifying embryo loss between fertilisation and implantation. The best available data for quantifying pregnancy loss come from three published prospective studies (Wilcox, Zinaman and Wang with daily cycle by cycle monitoring of human chorionic gonadotrophin (hCG in women attempting to conceive. Declining conception rates cycle by cycle in these studies indicate that a proportion of the study participants were sub-fertile. Hence, estimates of fecundability and pre-implantation embryo mortality obtained from the whole study cohort will inevitably be biased. This new re-analysis of aggregate data from these studies confirms the impression that discrete fertile and sub-fertile sub-cohorts were present. The proportion of sub-fertile women in the three studies was estimated as 28.1% (Wilcox, 22.8% (Zinaman and 6.0% (Wang. The probability of conceiving an hCG pregnancy (indicating embryo implantation was, respectively, 43.2%, 38.1% and 46.2% among normally fertile women, and 7.6%, 2.5% and 4.7% among sub-fertile women. Pre-implantation loss is impossible to calculate directly from available data although plausible limits can be estimated. Based on this new analysis and a model for evaluating reproductive success and failure it is proposed that a plausible range for normal human embryo and fetal mortality from fertilisation to birth is 40-60%.

  6. Efficient blastomere biopsy for mouse embryo splitting for future applications in human assisted reproduction.

    Science.gov (United States)

    Illmensee, K; Kaskar, K; Zavos, P M

    2005-12-01

    The objective of the current study was to establish a safe, efficient biopsy procedure for embryo splitting using the mouse model for future applications in human assisted reproduction. From mouse embryos at the 2-, 4-, 6- and 8-cell stage, half the number of blastomeres were microsurgically biopsied and transferred into empty mouse zonae pellucidae. Twin embryonic development was monitored during in-vitro culture. Blastocyst developmental rate using 2-, 4-, 6-, and 8-cell splitting was 74.4, 75.0, 66.7 and 38.4 respectively, with corresponding hatching rates of 94.9, 97.5, 92.7 and 83.8%. Blastocysts from 2-, 4-, and 6-cell splitting resulted in elevated hatching rates compared with non-operated blastocysts (87.5%), due to the Tyrode-assisted hatching effect. Blastocyst morphology was superior from 2- and 4-cell splitting when compared with 6- and 8-cell splitting. Furthermore, outgrowth of twin blastocysts from 2- and 4-cell splitting showed well-developed colonies with trophoblast cells and clusters of ICM cells, whereas those obtained from 6- and 8-cell splitting frequently formed small-sized colonies. Due to the high twinning success rate obtained under the experimental conditions employed in this study, it appears that with further modifications and proper safeguards, such embryo splitting efforts could have potential applications in humans.

  7. Preliminary study on human fibroblasts as feeder layer for human embryonic stem cells culture in vitro

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    To avoid the direct contact with mouse cells and possible heterogeneous pathogen in future application, we need to replace mouse embryonic fibroblastswith human fibroblasts as the feeder layer to maintain human embryonic stem cells growth in the undifferentiated state. We successfully use human fibroblasts derived from aborted fetus and adult prepuce as feeder layer to maintain human embryonic stem cells growth. During the passage and growth on this feeder layer, the human embryonic stem cells can keep their undifferentiated state.

  8. [The structure of the developing blood vessels of the neocortical anlage of the human embryo].

    Science.gov (United States)

    Korzhevskiĭ, D E; Omel'chenko, N V; Smirnov, E B; Petrova, E S

    2000-01-01

    Using light and electron microscopy the structure of blood vessels of neocortical anlage of human 7-12 embryos was studied. It was shown that at the early stage of formation of intraorgan vascular network the wall of blood vessels of ventricular zone successively differentiate, which is characterized by the appearance of second layer of cells (pericytes), accumulation of basement membrane components, widening of the zone of contacts between endotheliocytes and establishment of the contacts with bipolar cells of neocortex anlage. The morphological data obtained assist in comprehension of physiological aspects of formation of blood brain barrier and regulation of blood flow in human embryonal neocortex.

  9. Nucleosome Organization in Human Embryonic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Puya G Yazdi

    Full Text Available The fundamental repeating unit of eukaryotic chromatin is the nucleosome. Besides being involved in packaging DNA, nucleosome organization plays an important role in transcriptional regulation and cellular identity. Currently, there is much debate about the major determinants of the nucleosome architecture of a genome and its significance with little being known about its role in stem cells. To address these questions, we performed ultra-deep sequencing of nucleosomal DNA in two human embryonic stem cell lines and integrated our data with numerous epigenomic maps. Our analyses have revealed that the genome is a determinant of nucleosome organization with transcriptionally inactive regions characterized by a "ground state" of nucleosome profiles driven by underlying DNA sequences. DNA sequence preferences are associated with heterogeneous chromatin organization around transcription start sites. Transcription, histone modifications, and DNA methylation alter this "ground state" by having distinct effects on both nucleosome positioning and occupancy. As the transcriptional rate increases, nucleosomes become better positioned. Exons transcribed and included in the final spliced mRNA have distinct nucleosome profiles in comparison to exons not included at exon-exon junctions. Genes marked by the active modification H3K4m3 are characterized by lower nucleosome occupancy before the transcription start site compared to genes marked by the inactive modification H3K27m3, while bivalent domains, genes associated with both marks, lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin states are associated with unique nucleosome profiles. Nucleosome organization varies around transcription factor binding in enhancers versus promoters. DNA methylation is associated with increasing nucleosome occupancy and different types of methylations have distinct location preferences within the nucleosome core particle. Finally, computational

  10. Nucleosome Organization in Human Embryonic Stem Cells.

    Science.gov (United States)

    Yazdi, Puya G; Pedersen, Brian A; Taylor, Jared F; Khattab, Omar S; Chen, Yu-Han; Chen, Yumay; Jacobsen, Steven E; Wang, Ping H

    2015-01-01

    The fundamental repeating unit of eukaryotic chromatin is the nucleosome. Besides being involved in packaging DNA, nucleosome organization plays an important role in transcriptional regulation and cellular identity. Currently, there is much debate about the major determinants of the nucleosome architecture of a genome and its significance with little being known about its role in stem cells. To address these questions, we performed ultra-deep sequencing of nucleosomal DNA in two human embryonic stem cell lines and integrated our data with numerous epigenomic maps. Our analyses have revealed that the genome is a determinant of nucleosome organization with transcriptionally inactive regions characterized by a "ground state" of nucleosome profiles driven by underlying DNA sequences. DNA sequence preferences are associated with heterogeneous chromatin organization around transcription start sites. Transcription, histone modifications, and DNA methylation alter this "ground state" by having distinct effects on both nucleosome positioning and occupancy. As the transcriptional rate increases, nucleosomes become better positioned. Exons transcribed and included in the final spliced mRNA have distinct nucleosome profiles in comparison to exons not included at exon-exon junctions. Genes marked by the active modification H3K4m3 are characterized by lower nucleosome occupancy before the transcription start site compared to genes marked by the inactive modification H3K27m3, while bivalent domains, genes associated with both marks, lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin states) are associated with unique nucleosome profiles. Nucleosome organization varies around transcription factor binding in enhancers versus promoters. DNA methylation is associated with increasing nucleosome occupancy and different types of methylations have distinct location preferences within the nucleosome core particle. Finally, computational analysis of nucleosome

  11. Human Stem Cell Derived Cardiomyocytes: An Alternative ...

    Science.gov (United States)

    Chemical spills and associated deaths in the US has increased 2.6-fold and 16-fold from 1983 to 2012, respectfully. In addition, the number of chemicals to which humans are exposed to in the environment has increased almost 10-fold from 2001 to 2013 within the US. Internationally, a WHO report on the global composite impact of chemicals on health reported that 16% of the total burden of cardiovascular disease was attributed to environmental chemical exposure with 2.5 million deaths per year. Clearly, the cardiovascular system, at all its various developmental and life stages, represents a critical target organ system that can be adversely affected by existing and emerging chemicals (e.g., engineered nanomaterials) in a variety of environmental media. The ability to assess chemical cardiac risk and safety is critically needed but extremely challenging due to the number and categories of chemicals in commerce, as indicated. This presentation\\session will evaluate the use of adult human stem cell derived cardiomyocytes, and existing platforms, as an alternative model to evaluate environmental chemical cardiac toxicity as well as provide key information for the development of predictive adverse outcomes pathways associated with environmental chemical exposures. (This abstract does not represent EPA policy) Rapid and translatable chemical safety screening models for cardiotoxicity current status for informing regulatory decisions, a workshop sponsored by the Society

  12. Three-dimensional approach to stem cell therapy.

    OpenAIRE

    Oh, IL-Hoan; Kim, Dong-Wook

    2002-01-01

    Recent progress in stem cell research is opening a new hope for cell therapy in regenerative medicine. Two breakthroughs were made in the stem cell era, one, new discoveries in multi-potentiality of adult stem cells beyond the traditionally appreciated extent, and the other, establishment of pluripotent stem cell from human embryo. In addition to the newly identified multi-potentiality of adult stem cells, their ability to be trans-differentiated toward other tissue types (stem cell plasticit...

  13. Molecular aging and rejuvenation of human muscle stem cells

    DEFF Research Database (Denmark)

    Carlson, Morgan E; Suetta, Charlotte; Conboy, Michael J

    2009-01-01

    Very little remains known about the regulation of human organ stem cells (in general, and during the aging process), and most previous data were collected in short-lived rodents. We examined whether stem cell aging in rodents could be extrapolated to genetically and environmentally variable humans....... Our findings establish key evolutionarily conserved mechanisms of human stem cell aging. We find that satellite cells are maintained in aged human skeletal muscle, but fail to activate in response to muscle attrition, due to diminished activation of Notch compounded by elevated transforming growth...... factor beta (TGF-beta)/phospho Smad3 (pSmad3). Furthermore, this work reveals that mitogen-activated protein kinase (MAPK)/phosphate extracellular signal-regulated kinase (pERK) signalling declines in human muscle with age, and is important for activating Notch in human muscle stem cells. This molecular...

  14. Can the skull-spine length predict heart size in human embryos?

    Directory of Open Access Journals (Sweden)

    Maria Aimée Vila Bormey

    2012-11-01

    Full Text Available Background: embryo´s length is a global measure, relatively easy to estimate by trained personnel, and it is interesting to investigate its use as a predictor of the size reached by developing internal organs. Objective: To characterize cardiac development and its relationship to the length in human embryos. Methods: A descriptive, correlational and cross-sectional study was conducted at the University of Medical Sciences of Villa Clara, which included five specimens belonging to the Embrioteca of the Medicine School. The specimens were measured, processed trough paraffin method, transversally sectioned and digitalized with aesteroscopy-attached camera. 3.0 SCOPE PHOTO software was used for the study of the six cardiac variables. With SPSS 13,0 descriptive statistics was performed as well as correlation analysis and lineal regression. Results: In the weeks 6, 7 and 8, cardiac area was of 5,19; 4,66 and 8,02 mm2 and pericardiac area was of 7,11; 6,37 and 10,07 mm2. Anteroposterior cardiac diameter was of 2,33; 2,90 and 3,44 mm and transversally measured it was of 3,03; 2,52 and 3,65 mm. Anteroposterior pericardiac diameter was of 2,66; 3,37 and 3,61 mm and transversally measured it was of 3,35; 2,64 and 3,79 mm. Anteroposterior diameters of the heart and their cavity were significantly correlated to craneo-raquis length and lineal regression equations were obtained, thus allowing the calculation of these variables. Conclusions: The present study provides both, cardiac and pericardiac morphometrical values in human embryos between six and eight weeks. Craneo-raquis length in embryos can predict their cardiac and pericardiac size.

  15. The perfect host: a mouse host embryo facilitating more efficient germ line transmission of genetically modified embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Robert A Taft

    Full Text Available There is a continual need to improve efficiency in creating precise genetic modifications in mice using embryonic stem cells (ESCs. We describe a novel approach resulting in 100% germline transmission from competent injected ESCs. We developed an F1 mouse host embryo (Perfect Host, PH that selectively ablates its own germ cells via tissue-specific induction of diphtheria toxin. This approach allows competent microinjected ESCs to fully dominate the germline, eliminating competition for this critical niche in the developing and adult animal. This is in contrast to conventional methods, where competition from host germ cells results in offspring derived from host cells and ESCs, necessitating extensive breeding of chimeras and genotyping to identify germline. The germline transmission process is also complicated by variability in the actual number of ESCs that colonize the germline niche and the proportion that are germline competent. To validate the PH approach we used ESC lines derived from 129 F1, BALB/cByJ, and BTBR backgrounds as well as an iPS line. Resulting chimeric males produced 194 offspring, all paternally derived from the introduced stem cells, with no offspring being derived from the host genome. We further tested this approach using eleven genetically modified C57BL/6N ESC lines (International Knockout Mouse Consortium. ESC germline transmission was observed in 9/11 (82% lines using PH blastocysts, compared to 6/11 (55% when conventional host blastocysts were used. Furthermore, less than 35% (83/240 of mice born in the first litters from conventional chimeras were confirmed to be of ESC-origin. By comparison, 100% (137/137 of the first litter offspring of PH chimeras were confirmed as ESC-derived. Together, these data demonstrate that the PH approach increases the probability of germline transmission and speeds the generation of ESC derived animals from chimeras. Collectively, this approach reduces the time and costs inherent in the

  16. Epiblast ground state is controlled by canonical Wnt/β-catenin signaling in the postimplantation mouse embryo and epiblast stem cells.

    Directory of Open Access Journals (Sweden)

    Tomoyuki Sumi

    Full Text Available Epiblast stem cells (EpiSCs are primed pluripotent stem cells and can be derived from postimplantation mouse embryos. We now show that the absence of canonical Wnt/β-catenin signaling is essential for maintenance of the undifferentiated state in mouse EpiSCs and in the epiblast of mouse embryos. Attenuation of Wnt signaling with the small-molecule inhibitor XAV939 or deletion of the β-catenin gene blocked spontaneous differentiation of EpiSCs toward mesoderm and enhanced the expression of pluripotency factor genes, allowing propagation of EpiSCs as a homogeneous population. EpiSCs were efficiently established and propagated from single epiblast cells in the presence of both XAV939 and the Rho kinase (ROCK inhibitor Y27632. Cell transplantation revealed that EpiSCs were able to contribute to primordial germ cells and descendants of all three germ layers in a host embryo, suggesting that they maintained pluripotency, even after prolonged culture with XAV939. Such an improvement in the homogeneity of pluripotency achieved with the use of a Wnt inhibitor should prove advantageous for manipulation of primed pluripotent stem cells.

  17. Hematopoietic Development from Human Induced Pluripotent Stem Cells

    OpenAIRE

    2009-01-01

    A decade of research on human embryonic stem cells (ESC) has paved the way for the discovery of alternative approaches to generating pluripotent stem cells.Combinatorial overexpression of a limited number of proteins linked to pluripotency in ESC was recently found to reprogram differentiated somatic cells back to a pluripotent state, enabling the derivation of isogenic (patient-specific) pluripotent stem cell lines. Current research is focusing on improving reprogramming protocols (e.g. circ...

  18. Derivation and characterization of human embryonic stem cells on human amnion epithelial cells.

    Science.gov (United States)

    Lai, Dongmei; Wang, Yongwei; Sun, Jian; Chen, Yifei; Li, Ting; Wu, Yi; Guo, Lihe; Wei, Chunsheng

    2015-05-07

    Culture conditions that support the growth of undifferentiated human embryonic stem cells (hESCs) have already been established using primary human amnion epithelial cells (hAECs) as an alternative to traditional mitotically inactivated mouse embryonic fibroblasts (MEFs). In the present work, inner cell masses (ICM) were isolated from frozen embryos obtained as donations from couples undergoing in vitro fertilization (IVF) treatment and four new hESC lines were derived using hAECs as feeder cells. This feeder system was able to support continuous growth of what were, according to their domed shape and markers, undifferentiated naïve-like hESCs. Their pluripotent potential were also demonstrated by embryoid bodies developing to the expected three germ layers in vitro and the productions of teratoma in vivo. The cell lines retained their karyotypic integrity for over 35 passages. Transmission electron microscopy (TEM) indicated that these newly derived hESCs consisted mostly of undifferentiated cells with large nuclei and scanty cytoplasm. The new hESCs cultured on hAECs showed distinct undifferentiated characteristics in comparison to hESCs of the same passage maintained on MEFs. This type of optimized culture system may provide a useful platform for establishing clinical-grade hESCs and assessing the undifferentiated potential of hESCs.

  19. Induced pluripotent stem (iPS) cells from human fetal stem cells.

    Science.gov (United States)

    Guillot, Pascale V

    2016-02-01

    Pluripotency defines the ability of stem cells to differentiate into all the lineages of the three germ layers and self-renew indefinitely. Somatic cells can regain the developmental potential of embryonic stem cells following ectopic expression of a set of transcription factors or, in certain circumstances, via modulation of culture conditions and supplementation with small molecule, that is, induced pluripotent stem (iPS) cells. Here, we discuss the use of fetal tissues for reprogramming, focusing in particular on stem cells derived from human amniotic fluid, and the development of chemical reprogramming. We next address the advantages and disadvantages of deriving pluripotent cells from fetal tissues and the potential clinical applications.

  20. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells.

    Science.gov (United States)

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J; Bhatia, Mick

    2015-09-08

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs.

  1. Human embryonic stem cell lines derived from the Chinese population

    Institute of Scientific and Technical Information of China (English)

    Zhen Fu FANG; Fan JIN; Hui GAI; Ying CHEN; Li WU; Ai Lian LIU; Bin CHEN; Hui Zhen SHENG

    2005-01-01

    Six human embryonic stem cell lines were established from surplus blastocysts. The cell lines expressed alkaline phosphatase and molecules typical of primate embryonic stem cells, including Oct-4, Nanog, TDGF1, Sox2, EBAF,Thy-1, FGF4, Rex-1, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81. Five of the six lines formed embryoid bodies that expressed markers of a variety of cell types; four of them formed teratomas with tissue types representative of all three embryonic germ layers. These human embryonic stem cells are capable of producing clones of undifferentiated morphology, and one of them was propagated to become a subline. Human embryonic stem cell lines from the Chinese population should facilitate stem cell research and may be valuable in studies of population genetics and ecology.

  2. Early embryo mortality in natural human reproduction: What the data say [version 2; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Gavin E. Jarvis

    2017-06-01

    Full Text Available How many human embryos die between fertilisation and birth under natural conditions? It is widely accepted that natural human embryo mortality is high, particularly during the first weeks after fertilisation, with total prenatal losses of 70% and higher frequently claimed. However, the first external sign of pregnancy occurs two weeks after fertilisation with a missed menstrual period, and establishing the fate of embryos before this is challenging. Calculations are additionally hampered by a lack of data on the efficiency of fertilisation under natural conditions. Four distinct sources are used to justify quantitative claims regarding embryo loss: (i a hypothesis published by Roberts & Lowe in The Lancet  is widely cited but has no practical quantitative value; (ii life table analyses give consistent assessments of clinical pregnancy loss, but cannot illuminate losses at earlier stages of development; (iii studies that measure human chorionic gonadotrophin (hCG reveal losses in the second week of development and beyond, but not before; and (iv the classic studies of Hertig and Rock offer the only direct insight into the fate of human embryos from fertilisation under natural conditions. Re-examination of Hertig’s data demonstrates that his estimates for fertilisation rate and early embryo loss are highly imprecise and casts doubt on the validity of his numerical analysis. A recent re-analysis of hCG study data concluded that approximately 40-60% of embryos may be lost between fertilisation and birth, although this will vary substantially between individual women. In conclusion, natural human embryo mortality is lower than often claimed and widely accepted. Estimates for total prenatal mortality of 70% or higher are exaggerated and not supported by the available data.

  3. Evaluating the Expression of Mesenchymal Stem Cells Markers in Human Hair Follicle Stem Cells

    Directory of Open Access Journals (Sweden)

    Mohammadreza Behvarz

    2014-12-01

    Full Text Available Background & objectives: Adult stem cells are undifferentiated cells that replace dead or injured cells. There are adult stem cells in some regions of human tissues and hair follicle is one of the tissues that have adult stem cell source and these cells have an important role in hair life cycle. In this study, we investigated the isolation of hair follicle stem cells (HFSCs and expression of mesenchymal stem cell markers on the isolated cells.   Methods : Human hair follicles obtained from men scalp tissue by micro punch technique. Hair follicles isolated and cultured in culture flasks in DMEM-F12 + FBS. After outgrowth of stem cells from hair bulges, they analyzed by flow cytometry for detection of stem cell markers.  Results: 23 to 27 days after isolation and culture of HFSCs in uncoated cell culture flasks, cell surface markers expression studied by flow cytometry. Flow cytometric analysis showed 25.26% Stro-1, 50.85% CD90, 45.24% CD105, 61.20% CD44, 8.20% CD45, 11.86% CD146, 2.72% CD106, 7.21% CD166 and 26.74% CD19 expression in HFSCs.   Conclusion: In this study, isolated stem cells significantly expressed some of the mesenchymal stem cell markers higher than other markers. These markers give certain characteristics to HFSCs, and introduce the cells as an alternative option for cell therapy, tissue engineering and regenerative medicine.

  4. Generation of induced pluripotent stem cells from human blood.

    Science.gov (United States)

    Loh, Yuin-Han; Agarwal, Suneet; Park, In-Hyun; Urbach, Achia; Huo, Hongguang; Heffner, Garrett C; Kim, Kitai; Miller, Justine D; Ng, Kitwa; Daley, George Q

    2009-05-28

    Human dermal fibroblasts obtained by skin biopsy can be reprogrammed directly to pluripotency by the ectopic expression of defined transcription factors. Here, we describe the derivation of induced pluripotent stem cells from CD34+ mobilized human peripheral blood cells using retroviral transduction of OCT4/SOX2/KLF4/MYC. Blood-derived human induced pluripotent stem cells are indistinguishable from human embryonic stem cells with respect to morphology, expression of surface antigens, and pluripotency-associated transcription factors, DNA methylation status at pluripotent cell-specific genes, and the capacity to differentiate in vitro and in teratomas. The ability to reprogram cells from human blood will allow the generation of patient-specific stem cells for diseases in which the disease-causing somatic mutations are restricted to cells of the hematopoietic lineage.

  5. Evaluation of somatic embryos of alfalfa for recombinant protein expression.

    Science.gov (United States)

    Fu, Guohua; Grbic, Vojislava; Ma, Shengwu; Tian, Lining

    2015-02-01

    Somatic embryos of alfalfa can accumulate higher levels of recombinant proteins comparing to vegetative organs. Somatic embryos may be explored as a new system for new protein production for plants. Plants have been explored via genetic engineering as an inexpensive system for recombinant protein production. However, protein expression levels in vegetative tissues have been low, which limits the commercial utilization of plant expression systems. Somatic embryos resemble zygotic embryos in many aspects and may accumulate higher levels of proteins as true seed. In this study, somatic embryo of alfalfa (Medicago sativa L.) was investigated for the expression of recombinant proteins. Three heterologous genes, including the standard scientific reporter uid that codes for β-glucuronidase and two genes of interest: ctb coding for cholera toxin B subunit (CTB), and hIL-13 coding for human interleukin 13, were independently introduced into alfalfa via Agrobacterium-mediated transformation. Somatic embryos were subsequently induced from transgenic plants carrying these genes. Somatic embryos accumulated approximately twofold more recombinant proteins than vegetative organs including roots, stems, and leaves. The recombinant proteins of CTB and hIL-13 accumulated up to 0.15 and 0.18 % of total soluble protein in alfalfa somatic embryos, respectively. The recombinant proteins expressed in somatic embryos also exhibited biological activities. As somatic embryos can be induced in many plant species and their production can be scaled up via different avenues, somatic embryos may be developed as an efficient expression system for recombinant protein production.

  6. Phosphorylation dynamics during early differentiation of human embryonic stem cells

    NARCIS (Netherlands)

    van Hoof, D.; Munoz, J.; Braam, S.R.; Pinkse, M.W.H.; Linding, R.; Heck, A.J.R.; Mummery, C.L.; Krijgsveld, J.

    2009-01-01

    Pluripotent stem cells self-renew indefinitely and possess characteristic protein-protein networks that remodel during differentiation. How this occurs is poorly understood. Using quantitative mass spectrometry, we analyzed the (phospho)proteome of human embryonic stem cells (hESCs) during

  7. Phosphorylation dynamics during early differentiation of human embryonic stem cells

    NARCIS (Netherlands)

    van Hoof, D.; Munoz, J.; Braam, S.R.; Pinkse, M.W.H.; Linding, R.; Heck, A.J.R.; Mummery, C.L.; Krijgsveld, J.

    2009-01-01

    Pluripotent stem cells self-renew indefinitely and possess characteristic protein-protein networks that remodel during differentiation. How this occurs is poorly understood. Using quantitative mass spectrometry, we analyzed the (phospho)proteome of human embryonic stem cells (hESCs) during different

  8. Human tissue legislation in South Africa: Focus on stem cell ...

    African Journals Online (AJOL)

    2015-08-10

    Aug 10, 2015 ... The development of legislation is preceded by a policy document detailing the ... Most other stem cell types can be included in this broad definition. Pepper, ... appropriate legislative model in the fields of stem cell research and therapy. .... material for the purpose of reproductive cloning of a human being.

  9. Phosphorylation dynamics during early differentiation of human embryonic stem cells

    DEFF Research Database (Denmark)

    Van Hoof, Dennis; Muñoz, Javier; Braam, Stefan R

    2009-01-01

    Pluripotent stem cells self-renew indefinitely and possess characteristic protein-protein networks that remodel during differentiation. How this occurs is poorly understood. Using quantitative mass spectrometry, we analyzed the (phospho)proteome of human embryonic stem cells (hESCs) during...

  10. IGF-1/IGFBP-1 increases blastocyst formation and total blastocyst cell number in mouse embryo culture and facilitates the establishment of a stem-cell line

    Directory of Open Access Journals (Sweden)

    Hsu Teng-Tsao

    2003-09-01

    Full Text Available Abstract Background Apoptosis occurs frequently for blastocysts cultured in vitro, where conditions are suboptimal to those found in the natural environment. Insulin-like growth factor-1 (IGF-1 plays an important role in preventing apoptosis in the early development of the embryo, as well as in the progressive regulation of organ development. We hypothesize that IGF-1 and its dephosphorylated binding protein (IGFBP-1 may be able to improve embryo culture with an associated reduced cell death, and that the resultant increase in the total cell number of the embryo could increase the chances of establishing an embryonic stem-cell line. Results In vivo fertilized zygotes were cultured in medium containing supplementary IGF-1, or IGFBP-1/IGF-1. The stages of the resultant embryos were evaluated at noon on day five post-hCG injection. The extent of apoptosis and necrosis was evaluated using Annexin V and propidium iodine staining under fluorescent microscopy. The establishment of embryonic stem-cell lines was performed using the hatching blastocysts that were cultured in the presence of IGF-1 or IGFBP-1/IGF-1. The results show that the rate of blastocyst formation in a tissue-culture system in the presence of IGF-1 was 88.7% and IGFBP-1/IGF-1 it was 94.6%, respectively, and that it was significantly greater than the figure for the control group (81.9%. IGFBP-1/IGF-1 also resulted in a higher hatching rate than was the case for the control group (68.8% vs. 48.6% respectively. IGF-1 also increased the number of Annexin V-free and propidium iodine-free blastocysts in culture (86.8% vs. 75.9% respectively. Total cell number of blastocyst in culture was increased by 18.9% for those examples cultured with dephosphorylated IGFBP-1/IGF-1. For subsequent stem-cell culture, the chances of the successful establishment of a stem-cell line was increased for the IGF-1 and IGFBP-1/IGF-1 groups (IGF-1 vs. IGFBP-1/IGF-1 vs. control: 45.8% vs. 59.6% vs. 27

  11. Conservation of DNA Methylation Programming Between Mouse and Human Gametes and Preimplantation Embryos.

    Science.gov (United States)

    White, Carlee R; MacDonald, William A; Mann, Mellissa R W

    2016-09-01

    In mice, assisted reproductive technologies (ARTs) applied during gametogenesis and preimplantation development can result in disruption of genomic imprinting. In humans, these technologies and/or subfertility have been linked to perturbations in genomic imprinting. To understand how ARTs and infertility affect DNA methylation, it is important to understand DNA methylation dynamics and the role of regulatory factors at these critical stages. Recent genome studies performed using mouse and human gametes and preimplantation embryos have shed light onto these processes. Here, we comprehensively review the current state of knowledge regarding global and imprinted DNA methylation programming in the mouse and human. Available data highlight striking similarities in mouse and human DNA methylation dynamics during gamete and preimplantation development. Just as fascinating, these studies have revealed sex-, gene-, and allele-specific differences in DNA methylation programming, warranting future investigation to untangle the complex regulation of DNA methylation dynamics during gamete and preimplantation development.

  12. Early embryo mortality in natural human reproduction: What the data say [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Gavin E. Jarvis

    2016-11-01

    Full Text Available It is generally accepted that natural human embryo mortality during pregnancy is high – losses of 70% and higher from fertilisation to birth are frequently claimed. The first external sign of pregnancy occurs two weeks after fertilisation with a missed menstrual period. Establishing the fate of embryos before this is challenging, and hampered by a lack of data on the efficiency of fertilisation under natural conditions. Four distinct sources are cited to justify quantitative claims regarding embryo loss: (i a hypothesis published by Roberts & Lowe in The Lancet  is widely cited but has no quantitative value; (ii life table analyses give consistent assessments of clinical pregnancy loss, but cannot illuminate losses at earlier stages of development; (iii studies that measure human chorionic gonadotrophin (hCG reveal losses in the second week of development and beyond, but not before; and (iv the classic studies of Hertig and Rock offer the only direct insight into the fate of human embryos from fertilisation under natural conditions. Re-examination of Hertig’s data demonstrates that his estimates for fertilisation rate and early embryo loss are highly imprecise and casts doubt on the validity of his numerical analysis. A recent re-analysis of hCG study data suggests that approximately 40-60% of embryos may be lost between fertilisation and birth, although this will vary substantially between individual women. In conclusion, it is clear that some published estimates of natural embryo mortality are exaggerated. Although available data do not provide a precise estimate, natural human embryo mortality is lower than is often claimed.

  13. Human embryonic stem cells and microenvironment

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2014-09-01

    Full Text Available Human embryonic stem cells (hESCs possess a great potential in the field of regenerative medicine by their virtue of pluripotent potential with indefinite proliferation capabilities. They can self renew themselves and differentiate into three embryonic germ layers. Although they are conventionally grown on mitotically inactivated mouse feeder cells, there are in vitro culture systems utilizing feeder cells of human origin in order to prevent cross-species contamination. Recently established in vitro culture systems suggested that direct interaction with feeder cells is not necessary but rather attachment to a substrate is required to ensure long-term, efficient hESC culture in vitro. This substrate is usually composed of a mixture of extracellular matrix components representing in vivo natural niche. In hESC biology, the mechanism of interaction of hESCs with extracellular matrix molecules remained insufficiently explored area of research due to their transient nature of interaction with the in vivo niche. However, an in vitro culture system established using extracellular matrix molecules may provide a safer alternative to culture systems with feeder cells while paving the way to Good Manufacturing Practice-GMP production of hESCs for therapeutic purposes. Therefore, it is essential to study the interaction of extracellular matrix molecules with hESCs in order to standardize in vitro culture systems for large-scale production of hESCs in a less labor-intensive way. This would not only provide valuable information regarding the mechanisms that control pluripotency but also serve to dissect the molecular signaling pathways of directed differentiation for prospective therapeutic applications in the future. J Clin Exp Invest 2014; 5 (3: 486-495

  14. Generation of KCL025 research grade human embryonic stem cell line carrying a mutation in NF1 gene

    Directory of Open Access Journals (Sweden)

    Heema Hewitson

    2016-03-01

    Full Text Available The KCL025 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation in the NF1 gene encoding neurofibromin (c.3739–3742 ΔTTTG. Mutations in this gene have been linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  15. Generation of KCL018 research grade human embryonic stem cell line carrying a mutation in the DMPK gene

    Directory of Open Access Journals (Sweden)

    Cristian Miere

    2016-03-01

    Full Text Available The KCL018 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation affecting one allele of the DMPK gene encoding the dystrophia myotonica protein kinase (2200 trinucleotide repeats; 14 for the normal allele. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro assays.

  16. Generation of KCL028 research grade human embryonic stem cell line carrying a mutation in the HTT gene

    Directory of Open Access Journals (Sweden)

    Laureen Jacquet

    2016-03-01

    Full Text Available The KCL028 human embryonic stem cell line was derived from an embryo donated for research that carried an autosomal dominant mutation affecting one allele of the HTT gene encoding huntingtin (43 trinucleotide repeats; 21 for the normal allele. The ICM was isolated using laser microsurgery and plated on γ-irradiated human foreskin fibroblasts. Both the derivation and cell line propagation were performed in an animal product-free environment. Pluripotent state and differentiation potential were confirmed by in vitro and in vivo assays.

  17. Stem Cells, Science, and Public Reasoning

    Science.gov (United States)

    Hurlbut, J. Benjamin; Robert, Jason Scott

    2012-01-01

    These are interesting days in the scientific, social, and political debates about human embryonic stem cell research. Pluripotent stem cells--cells that can, in principle, give rise to the body's full range of cell types--were previously derivable only from human embryos that were destroyed in the process. Now, a variety of somatic cell types can…

  18. Stem Cells, Science, and Public Reasoning

    Science.gov (United States)

    Hurlbut, J. Benjamin; Robert, Jason Scott

    2012-01-01

    These are interesting days in the scientific, social, and political debates about human embryonic stem cell research. Pluripotent stem cells--cells that can, in principle, give rise to the body's full range of cell types--were previously derivable only from human embryos that were destroyed in the process. Now, a variety of somatic cell types can…

  19. Therapeutic potentials of human embryonic stem cells in Parkinson's disease

    National Research Council Canada - National Science Library

    Newman, Mary B; Bakay, Roy A E

    2008-01-01

    .... The isolation, differentiation, and long-term cultivation of human embryonic stem cells and the therapeutic research discovery made in relation to the beneficial properties of neurotrophic and neural...

  20. Identification of a candidate stem cell in human gallbladder

    Directory of Open Access Journals (Sweden)

    Rohan Manohar

    2015-05-01

    In conclusion, we have isolated a distinct clonogenic population of epithelial cells from primary human fetal gallbladder with stem cell characteristics and found it to be unique compared to IHBD cells.

  1. Derivation of multipotent mesenchymal precursors from human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    2005-06-01

    Full Text Available BACKGROUND: Human embryonic stem cells provide access to the earliest stages of human development and may serve as a source of specialized cells for regenerative medicine. Thus, it becomes crucial to develop protocols for the directed differentiation of embryonic stem cells into tissue-restricted precursors. METHODS AND FINDINGS: Here, we present culture conditions for the derivation of unlimited numbers of pure mesenchymal precursors from human embryonic stem cells and demonstrate multilineage differentiation into fat, cartilage, bone, and skeletal muscle cells. CONCLUSION: Our findings will help to elucidate the mechanism of mesoderm specification during embryonic stem cell differentiation and provide a platform to efficiently generate specialized human mesenchymal cell types for future clinical applications.

  2. Embryonic catalase protects against ethanol embryopathies in acatalasemic mice and transgenic human catalase-expressing mice in embryo culture.

    Science.gov (United States)

    Miller-Pinsler, Lutfiya; Wells, Peter G

    2015-09-15

    Reactive oxygen species (ROS) have been implicated in the mechanism of ethanol (EtOH) teratogenicity, but the protective role of the embryonic antioxidative enzyme catalase is unclear, as embryonic activity is only about 5% of maternal levels. We addressed this question in a whole embryo culture model. C57BL/6 mouse embryos expressing human catalase (hCat) or their wild-type (C57BL/6 WT) controls, and C3Ga.Cg-Cat(b)/J catalase-deficient, acatalasemic (aCat) mouse embryos or their wild-type C3HeB/FeJ (C3H WT) controls, were explanted on gestational day (GD) 9 (plug=GD 1), exposed for 24h to 2 or 4mg/mL EtOH or vehicle, and evaluated for functional and morphological changes. hCat and C57BL/6 WT vehicle-exposed embryos developed normally, while EtOH was embryopathic in C57BL/6 WT embryos, evidenced by decreases in anterior neuropore closure, somites developed, turning and head length, whereas hCat embryos were protected (pcatalase (PEG-cat) 8h prior to embryo culture, which increases embryonic catalase activity, blocked all EtOH embryopathies (pcatalase is a determinant of risk for EtOH embryopathies.

  3. Production of human lysozyme-transgenic cloned porcine embryos by somatic nuclear transfer

    Institute of Scientific and Technical Information of China (English)

    Qiuyan Li; Hengxi Wei; Ying Guo; Yan Li; Rui Zhao; Yufang Ma; Zhengquan Yu; Bo Tang; Lei Zhang; Yunping Dai; Ning Li

    2009-01-01

    Due to their physiology and organ size, pigs have significant potential as human disease models and as organ transplantation donors. Genetic modification of pigs could provide benefits for both agriculture and human medicine. In this study, five fetal pig fibroblast cell lines from two species (Wuzhishan and Landrace pigs) were transfected using double-marked human lysozyme (HLY) plasmids (pBC1-HLY-GFP-NEO) by a liposome-mediated method. The ratio of green fluorescent protein (GFP)-expressing cells was >95% in sw7, sw8, s1w3 and s1w6 cell lines, but only 49.3% in slw9 cells. Cells from the four highly transgenic lines were used as nuclear donors to construct embryos, which were then cultured after fusion and activation by electric stimulation. The rate of cleavage was 76.7%, 48 h after acti-vation. After 7 days, 18.5% of cleaved eggs had developed to the blastocyst stage and 93.3% of blastocysts were GFP-positive. These results indicate that transgenic fetal pig fibroblast cell lines could be obtained by a liposome-mediated method, though the transfection efficiency varied between cell lines. Reconstructed embryos derived from transgenic cells could successfully develop into blastocysts, most of which were GFP-positive.

  4. New perspectives in human stem cell therapeutic research

    Directory of Open Access Journals (Sweden)

    Trounson Alan

    2009-06-01

    Full Text Available Abstract Human stem cells are in evaluation in clinical stem cell trials, primarily as autologous bone marrow studies, autologous and allogenic mesenchymal stem cell trials, and some allogenic neural stem cell transplantation projects. Safety and efficacy are being addressed for a number of disease state applications. There is considerable data supporting safety of bone marrow and mesenchymal stem cell transplants but the efficacy data are variable and of mixed benefit. Mechanisms of action of many of these cells are unknown and this raises the concern of unpredictable results in the future. Nevertheless there is considerable optimism that immune suppression and anti-inflammatory properties of mesenchymal stem cells will be of benefit for many conditions such as graft versus host disease, solid organ transplants and pulmonary fibrosis. Where bone marrow and mesenchymal stem cells are being studied for heart disease, stroke and other neurodegenerative disorders, again progress is mixed and mostly without significant benefit. However, correction of multiple sclerosis, at least in the short term is encouraging. Clinical trials on the use of embryonic stem cell derivatives for spinal injury and macular degeneration are beginning and a raft of other clinical trials can be expected soon, for example, the use of neural stem cells for killing inoperable glioma and embryonic stem cells for regenerating β islet cells for diabetes. The change in attitude to embryonic stem cell research with the incoming Obama administration heralds a new co-operative environment for study and evaluation of stem cell therapies. The Californian stem cell initiative (California Institute for Regenerative Medicine has engendered global collaboration for this new medicine that will now also be supported by the US Federal Government. The active participation of governments, academia, biotechnology, pharmaceutical companies, and private investment is a powerful consortium for

  5. The race toward 'ethically universally acceptable' human pluripotent (embryonic-like) stem cells: only a problem of sources?

    Science.gov (United States)

    Neri, Demetrio

    2011-06-01

    Over the past few years, several proposals aimed at procuring human pluripotent (embryonic-like) stem cells without involving the destruction of a human embryo have been proposed and widely discussed. This article focuses on a basic aspect of the debate, namely the plausibility of one or more of these new proposals being able to meet the ethical requirements that those who regard the human embryo as sacred have tried to impose on stem cells research in the last ten years. The thesis of the article is that focusing the discussion only on the sources of stem cells has prevented a full understanding of the foundation, meaning and scope of these ethical requirements. To substantiate this thesis, the article takes into consideration two issues: the first has to do with the potential of the cells obtained through some of the new approaches (iPS included), the second (and decisive) with the argument of the 'indirect complicity', applied to the use of 'contaminated' knowledge.

  6. ISOLATION AND EXPANSION OF HUMAN EMBRYONIC NEURAL STEM/PROGENITOR CELLS IN VITRO

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective: To isolate, culture and identify human embryonic neural stem cells and to establish a practical passaging method. Method:The cerebral cortex cells were isolated from aborted embryos (11~13 weeks)by mechanical dissociation, and cultured in DMEM/F12 culture medium supplemented with N2 and growth factors for proliferation. Upon passaging, the neurospheres were pipetted gentlely to separate them into several cell masses and then grown in growth medium. The cells were grown in DMEM/F12 medium with serum (without growth factors) to induce differentiation. The stem cell, neuron, astrocyte and oligodendrocyte were identified by immunocytochemistry with antibodies to vimentin, MAP2, GFAP and GalC, respectively. Results:The primary cells grew together and formed neurospheres at 5th~7th day. They were all vimentin positive and could be passaged for at least 8passages. After passaging, the cell masses grew up and formed new neurospheres rapidly. These cells could differentiated into MAP2 ( + ), GFAP( + ) or GalC( + ) cells. Conclusion: The neural stem cells from human embryonic cerebral cortex have the capacity of proliferation and multi - differentiation in vitro. The passaging methods we used in this experiment were practical and convenient.

  7. Advances in stem cell research

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In 1998, biologists Thomson and Gearhart successfully derived stem cells from human embryos. One year later, several researchers discovered that adult stem cells still retain the ability to be differentiated into unrelated types of cells. Advances in stem cell research open a promising direction for applied medical science. Moreover, it may also force scientists to reconsider the fundamental theory about how cells grow up. Stem cell research was considered by Science as the top of the ten breakthroughs of science of the year[1]. This paper gives a survey of recent advances in stem cell research. 1 Overview In the 1980s, embryonic stem cell and/or embryonic germ cell line (ES cell line, EG cell line) of multifarious mammalian animals, especially those of non-human pri-mates, had been established. In 1998, Thomson and Shamblott obtained ES, EG cell lines from human blasto-cysts and gonad ridges of early human embryos, respec-tively. Their research brought up an ethical debate about whether human embryos can be used as experimental materials. It was not appeased until 1999 when research-ers discovered that stem cells from adults still retain the ability to become different kinds of tissue cells. For in-stance, brain cells can become blood cells[2], and cells from bone marrow can become cells in liver. Scientists believe, for a long time, that cells can only be developed from early pluripotent embryo cells; the differentiation potential of stem cells from mature tissues is restricted to only one of the cell types of the tissue where stem cells are obtained. Recent stem cell researches, however, sub-verted the traditional view of stem cells. These discoveries made scientists speed ahead with the work on adult stem cells, hoping to discover whether their promise will rival that of ES cells.

  8. Glycomics of human embryonic stem cells and human induced pluripotent stem cells.

    Science.gov (United States)

    Furukawa, Jun-Ichi; Okada, Kazue; Shinohara, Yasuro

    2016-10-01

    Most cells are coated by a dense glycocalyx composed of glycoconjugates such as glycosphingolipids, glycoproteins, and proteoglycans. The overall glycomic profile is believed to be crucial for the diverse roles of glycans, which are mediated by specific interactions that regulate cell-cell adhesion, the immune response, microbial pathogenesis, and other cellular events. Many cell surface markers were discovered and identified as glycoconjugates such as stage-specific embryonic antigen, Tra-1-60/81 and various other cell surface molecules (e.g., cluster of differentiation). Recent progress in the development of analytical methodologies and strategies has begun to clarify the cellular glycomics of various cells including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). The glycomic profiles of these cells are highly cell type-specific and reflect cellular alterations, such as development, differentiation and cancerous change. In this mini review, we briefly summarize the glycosylation spectra specific to hESCs and hiPSCs, which cover glycans of all major glycoconjugates (i.e., glycosphingolipids, N- and O-glycans of glycoproteins, and glycosaminoglycans) and free oligosaccharides.

  9. Development of hematopoietic stem and progenitor cells from human pluripotent stem cells.

    Science.gov (United States)

    Chen, Tong; Wang, Fen; Wu, Mengyao; Wang, Zack Z

    2015-07-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), provide a new cell source for regenerative medicine, disease modeling, drug discovery, and preclinical toxicity screening. Understanding of the onset and the sequential process of hematopoietic cells from differentiated hPSCs will enable the achievement of personalized medicine and provide an in vitro platform for studying of human hematopoietic development and disease. During embryogenesis, hemogenic endothelial cells, a specified subset of endothelial cells in embryonic endothelium, are the primary source of multipotent hematopoietic stem cells. In this review, we discuss current status in the generation of multipotent hematopoietic stem and progenitor cells from hPSCs via hemogenic endothelial cells. We also review the achievements in direct reprogramming from non-hematopoietic cells to hematopoietic stem and progenitor cells. Further characterization of hematopoietic differentiation in hPSCs will improve our understanding of blood development and expedite the development of hPSC-derived blood products for therapeutic purpose.

  10. Stem cell markers in the heart of the human newborn

    Directory of Open Access Journals (Sweden)

    Armando Faa

    2016-07-01

    Full Text Available The identification of cardiac progenitor cells in mammals raises the possibility that the human heart contains a population of stem cells capable of generating cardiomyocytes and coronary vessels. Several recent studies now show that the different cell types that characterize the adult human heart arise from a common ancestor. Human cardiac stem cells differentiate into cardiomyocytes, and, in lesser extent, into smooth muscle and endothelial cells. The characterization of human cardiac stem cells (CSCs has important clinical implications. In recent years, CD117 (c-kit has been reported to mark a subtype of stem/progenitor cells in the human heart, with stem cell-like properties, including the ability to self-renewal and clonogenicity multipotentiality. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano

  11. Genetic recombination pathways and their application for genome modification of human embryonic stem cells.

    Science.gov (United States)

    Nieminen, Mikko; Tuuri, Timo; Savilahti, Harri

    2010-10-01

    Human embryonic stem cells are pluripotent cells derived from early human embryo and retain a potential to differentiate into all adult cell types. They provide vast opportunities in cell replacement therapies and are expected to become significant tools in drug discovery as well as in the studies of cellular and developmental functions of human genes. The progress in applying different types of DNA recombination reactions for genome modification in a variety of eukaryotic cell types has provided means to utilize recombination-based strategies also in human embryonic stem cells. Homologous recombination-based methods, particularly those utilizing extended homologous regions and those employing zinc finger nucleases to boost genomic integration, have shown their usefulness in efficient genome modification. Site-specific recombination systems are potent genome modifiers, and they can be used to integrate DNA into loci that contain an appropriate recombination signal sequence, either naturally occurring or suitably pre-engineered. Non-homologous recombination can be used to generate random integrations in genomes relatively effortlessly, albeit with a moderate efficiency and precision. DNA transposition-based strategies offer substantially more efficient random strategies and provide means to generate single-copy insertions, thus potentiating the generation of genome-wide insertion libraries applicable in genetic screens.

  12. Electrical Guidance of Human Stem Cells in the Rat Brain

    Directory of Open Access Journals (Sweden)

    Jun-Feng Feng

    2017-07-01

    Full Text Available Limited migration of neural stem cells in adult brain is a roadblock for the use of stem cell therapies to treat brain diseases and injuries. Here, we report a strategy that mobilizes and guides migration of stem cells in the brain in vivo. We developed a safe stimulation paradigm to deliver directional currents in the brain. Tracking cells expressing GFP demonstrated electrical mobilization and guidance of migration of human neural stem cells, even against co-existing intrinsic cues in the rostral migration stream. Transplanted cells were observed at 3 weeks and 4 months after stimulation in areas guided by the stimulation currents, and with indications of differentiation. Electrical stimulation thus may provide a potential approach to facilitate brain stem cell therapies.

  13. Prospect of Human Pluripotent Stem Cell-Derived Neural Crest Stem Cells in Clinical Application

    Directory of Open Access Journals (Sweden)

    Qian Zhu

    2016-01-01

    Full Text Available Neural crest stem cells (NCSCs represent a transient and multipotent cell population that contributes to numerous anatomical structures such as peripheral nervous system, teeth, and cornea. NCSC maldevelopment is related to various human diseases including pigmentation abnormalities, disorders affecting autonomic nervous system, and malformations of teeth, eyes, and hearts. As human pluripotent stem cells including human embryonic stem cells (hESCs and human induced pluripotent stem cells (hiPSCs can serve as an unlimited cell source to generate NCSCs, hESC/hiPSC-derived NCSCs can be a valuable tool to study the underlying mechanisms of NCSC-associated diseases, which paves the way for future therapies for these abnormalities. In addition, hESC/hiPSC-derived NCSCs with the capability of differentiating to various cell types are highly promising for clinical organ repair and regeneration. In this review, we first discuss NCSC generation methods from human pluripotent stem cells and differentiation mechanism of NCSCs. Then we focus on the clinical application potential of hESC/hiPSC-derived NCSCs on peripheral nerve injuries, corneal blindness, tooth regeneration, pathological melanogenesis, Hirschsprung disease, and cardiac repair and regeneration.

  14. Prospect of Human Pluripotent Stem Cell-Derived Neural Crest Stem Cells in Clinical Application

    Science.gov (United States)

    Zhu, Qian; Lu, Qiqi; Gao, Rong

    2016-01-01

    Neural crest stem cells (NCSCs) represent a transient and multipotent cell population that contributes to numerous anatomical structures such as peripheral nervous system, teeth, and cornea. NCSC maldevelopment is related to various human diseases including pigmentation abnormalities, disorders affecting autonomic nervous system, and malformations of teeth, eyes, and hearts. As human pluripotent stem cells including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) can serve as an unlimited cell source to generate NCSCs, hESC/hiPSC-derived NCSCs can be a valuable tool to study the underlying mechanisms of NCSC-associated diseases, which paves the way for future therapies for these abnormalities. In addition, hESC/hiPSC-derived NCSCs with the capability of differentiating to various cell types are highly promising for clinical organ repair and regeneration. In this review, we first discuss NCSC generation methods from human pluripotent stem cells and differentiation mechanism of NCSCs. Then we focus on the clinical application potential of hESC/hiPSC-derived NCSCs on peripheral nerve injuries, corneal blindness, tooth regeneration, pathological melanogenesis, Hirschsprung disease, and cardiac repair and regeneration. PMID:28090209

  15. Neural Differentiation of Human Umbilical Cord Mesenchymal Stem Cells by Cerebrospinal Fluid

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    Shirin FARIVAR*

    2015-01-01

    fluid. J Neurol Neurosurg Psychiatry 1995 Oct;59(4:349-57.Alcazar A, Regidor I, Masjuan J, Salinas M, Alvarez- Cermeno JC. Induction of apoptosis by cerebrospinal fluid from patients with primary-progressive multiple sclerosis in cultured neurons. Neurosci Lett 1998 Oct 16;255(2:75-8.Colombo JA, Napp MI. Cerebrospinal fluid from L-dopa-treated Parkinson’s disease patients is dystrophic for various neural cell types exvivo: effects of astroglia. Exp Neurol 1998 Dec;154(2:452-63.Redzic ZB, Preston JE, Duncan JA, Chodobski A, Szmydynger-Chodobska J. The choroid plexus-cerebrospinal fluid system: from development to aging. Current topics in developmental biology 2005; (71: 1-52.Bachy I, Kozyraki R, Wassef M. The particles of the embryonic cerebrospinal fluid: how could they influence brain development? Brain Res Bull 2008 Mar 18;75(2- 4:289-94. doi: 10.1016/j.brainresbull.2007.10.010.Parada C, Gato A, Bueno D. Mammalian embryonic cerebrospinal fluid proteome has greater apo-lipoprotein and enzyme pattern complexity than the avian proteome. Journal of proteome research 2005; 4(6: 2420- 2428.Martin C, Bueno D, Alonso MI, Moro JA, Callejo S, Parada C, Martin P, Carnicero E, Gato A. FGF2 plays a key role in embryonic cerebrospinal fluid trophic properties over chick embryo neuro epithelial stem cells. Dev Biol 2006 Sep 15;297(2:402-16. Epub 2006 May 19.Huttner HB, Janich P, Kohrmann M, Jaszai J, Siebzehnrubl F, Blumcke I, Suttorp M, Gahr M, Kuhnt D, Nimsky C. The stem cell markerprominin-1/CD133 on membrane particles in human cerebrospinal fluid offers novel approaches for studying central nervous system disease. Stem Cells 2008 Mar;26(3:698-705.Nordin C, Gupta RC, Sjodin I. Cerebrospinal fluid amino acids in pathological gamblers and healthy controls. Neuropsychobiology 2007;56(2-3:152-8. doi: 10.1159/000115782. Epub 2008 Feb 7.Gato A, Martin P, Alonso MI, Martin C, Pulgar MA, Moro JA. Analysis of cerebro-spinal fluid protein composition in early developmental stages in

  16. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  17. Establishment of human embryonic stem cell lines from frozen-thawed blastocysts using STO cell feeder layers.

    Science.gov (United States)

    Park, Se-Pill; Lee, Young Jae; Lee, Keum Sil; Ah Shin, Hyun; Cho, Hwang Yoon; Chung, Kil Saeng; Kim, Eun Young; Lim, Jin Ho

    2004-03-01

    Recently, human embryonic stem (hES) cells have become very important resources for basic research on cell replacement therapy and other medical applications. The purpose of this study was to test whether pluripotent hES cell lines could be successfully derived from frozen-thawed embryos that were destined to be discarded after 5 years in a routine human IVF-embryo transfer programme and whether an STO cell feeder layer can be used for the culture of hES cells. Donated frozen embryos (blastocysts or pronuclear) were thawed, and recovered or in vitro developed blastocysts were immunosurgically treated. All inner cell masses were cultured continuously on an STO cell feeder layer and then presumed hES cell colonies were characterized. Seven and two cell lines were established from frozen-thawed blastocysts (7/20, 35.0%) and pronuclear stage embryos (2/20, 10.0%), respectively. The doubling time of hES cells on the immortal STO cell feeder layer was approximately 36 h, similar to that of cells grown using fresh mouse embryonic fibroblast (MEF) feeder conditions. Subcultured hES cell colonies showed strong positive immunostaining for alkaline phosphatase, stage-specific embryonic antigen-4 (SSEA-4) and tumour rejection antigen 1-60 (TRA1-60) cell surface markers. Also, the hES colonies retained normal karyotypes and Oct-4 expression in prolonged subculture. When in vitro differentiation of hES cells was induced by retinoic acid, three embryonic germ layer cells were identified by RT-PCR or indirect immunocytochemistry. This study indicates that establishment of hES cells from frozen-thawed blastocysts minimizes the ethical problem associated with the use of human embryos in research and that the STO cell feeder layer can be used for the culture of hES cells.

  18. The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis

    OpenAIRE

    Danilo Cimadomo; Antonio Capalbo; Filippo Maria Ubaldi; Catello Scarica; Antonio Palagiano; Rita Canipari; Laura Rienzi

    2016-01-01

    Preimplantation Genetic Diagnosis and Screening (PGD/PGS) for monogenic diseases and/or numerical/structural chromosomal abnormalities is a tool for embryo testing aimed at identifying nonaffected and/or euploid embryos in a cohort produced during an IVF cycle. A critical aspect of this technology is the potential detrimental effect that the biopsy itself can have upon the embryo. Different embryo biopsy strategies have been proposed. Cleavage stage blastomere biopsy still represents the most...

  19. Characterizing human herpes virus 6 following hematopoietic stem cell transplantation.

    Science.gov (United States)

    Perissinotti, Anthony J; Gulbis, Alison; Shpall, Elizabeth J; Howell, Joshua

    2015-04-01

    Human herpes virus 6 reactivation occurs in approximately 50% of patients following hematopoietic stem cell transplant, however, the significance of human herpes virus 6 reactivation remains uncertain. A retrospective study was conducted analyzing clinical data of patients testing positive for human herpes virus 6 by quantitative polymerase chain reaction following hematopoietic stem cell transplant from 1 January 1998 to 1 October 2011. Data retrieved were used to describe the clinical course and outcome of human herpes virus 6 positive hematopoietic stem cell transplant patients. Sixty patients were identified who tested positive for human herpes virus 6 by polymerase chain reaction following hematopoietic stem cell transplant. A high proportion of patients were identified in this cohort with acute myeloid leukemia (28.3%), active disease (65%), transplanted with a matched unrelated donor (30%), ≥ 1 antigen mismatched (28.3%) matched unrelated donor, or an umbilical cord graft (25%), and those who received antithymocyte globulin (42.4%). Thirty-eight (63.3%) patients were treated for human herpes virus 6 with foscarnet alone or in combination with intravenous immunoglobulin, whereas 18 (30%) did not require treatment survival at Day 100 was 73.3%. This study suggests human herpes virus 6 reactivation occurs shortly after hematopoietic stem cell transplant (median of 25 days (interquartile range, 20-31.75) after hematopoietic stem cell transplant). Many potential risk factors are described in this report. Treatment of human herpes virus 6 predominately consisted of foscarnet with or without intravenous immunoglobulin; however, treatment of human herpes virus 6 was not always warranted. Furthermore, the effect of treatment on patient outcomes is uncertain. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  20. Derivation of human embryonic stem cells in defined conditions.

    Science.gov (United States)

    Ludwig, Tenneille E; Levenstein, Mark E; Jones, Jeffrey M; Berggren, W Travis; Mitchen, Erika R; Frane, Jennifer L; Crandall, Leann J; Daigh, Christine A; Conard, Kevin R; Piekarczyk, Marian S; Llanas, Rachel A; Thomson, James A

    2006-02-01

    We have previously reported that high concentrations of basic fibroblast growth factor (bFGF) support feeder-independent growth of human embryonic stem (ES) cells, but those conditions included poorly defined serum and matrix components. Here we report feeder-independent human ES cell culture that includes protein components solely derived from recombinant sources or purified from human material. We describe the derivation of two new human ES cell lines in these defined culture conditions.

  1. Cancer genes hypermethylated in human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Vincenzo Calvanese

    Full Text Available Developmental genes are silenced in embryonic stem cells by a bivalent histone-based chromatin mark. It has been proposed that this mark also confers a predisposition to aberrant DNA promoter hypermethylation of tumor suppressor genes (TSGs in cancer. We report here that silencing of a significant proportion of these TSGs in human embryonic and adult stem cells is associated with promoter DNA hypermethylation. Our results indicate a role for DNA methylation in the control of gene expression in human stem cells and suggest that, for genes repressed by promoter hypermethylation in stem cells in vivo, the aberrant process in cancer could be understood as a defect in establishing an unmethylated promoter during differentiation, rather than as an anomalous process of de novo hypermethylation.

  2. Human Placenta: a Source of Progenitor/Stem Cells?

    Directory of Open Access Journals (Sweden)

    Parolini O

    2006-01-01

    Full Text Available Regenerative medicine based on cell therapy and tissue engineering methodologies is a newly emerging, multidisciplinary field involving biology, medicine, and genetic manipulation. This type of therapy is aimed at maintaining, restoring, or enhancing tissue and organ function, and is intended to assist in the treatment of a number of human conditions which range in severity from chronic to life threatening. In diseases where tissue or organ function is compromised, stem cell research holds great promise for providing an efficient avenue for regenerative therapy. However, the application of this type of research to the treatment of human disease will not be possible until much more is known about the biological properties of all types of stem cells. In the context of disease treatment, decisions will need to be made as to which is the best type of stem cell to use. Whether it is better to identify a stem cell able to differentiate into all tissue and organ types as opposed to using committed, lineage-specific stem cells, or perhaps embryonic cells are better than adult-derived stem cells, as well as the possible clinical applications of these cells. For some time, these questions have not only required significant scientific and medical consideration, but have also posed important social and ethical questions. There is no doubt that stem cells hold great therapeutic potential, however there is still much research required before their use can be accepted as a valuable tool in disease treatment. In particular, it is necessary to identify a source of stem cells that is easily accessible, provides a high cell yield and for which cell recovery does not provoke serious ethical debate. The aim of this review is to consider and discuss the findings regarding a new source of "adult" stem cells isolated from human term placenta tissue. So far, the placental tissue has generally been discarded post partum, but it is now becoming recognised as a potential

  3. Alloimmune Responses of Humanized Mice to Human Pluripotent Stem Cell Therapeutics

    Directory of Open Access Journals (Sweden)

    Nigel G. Kooreman

    2017-08-01

    Full Text Available There is growing interest in using embryonic stem cell (ESC and induced pluripotent stem cell (iPSC derivatives for tissue regeneration. However, an increased understanding of human immune responses to stem cell-derived allografts is necessary for maintaining long-term graft persistence. To model this alloimmunity, humanized mice engrafted with human hematopoietic and immune cells could prove to be useful. In this study, an in-depth analysis of graft-infiltrating human lymphocytes and splenocytes revealed that humanized mice incompletely model human immune responses toward allogeneic stem cells and their derivatives. Furthermore, using an “allogenized” mouse model, we show the feasibility of reconstituting immunodeficient mice with a functional mouse immune system and describe a key role of innate immune cells in the rejection of mouse stem cell allografts.

  4. Human pluripotent stem cells: an emerging model in developmental biology.

    Science.gov (United States)

    Zhu, Zengrong; Huangfu, Danwei

    2013-02-01

    Developmental biology has long benefited from studies of classic model organisms. Recently, human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, have emerged as a new model system that offers unique advantages for developmental studies. Here, we discuss how studies of hPSCs can complement classic approaches using model organisms, and how hPSCs can be used to recapitulate aspects of human embryonic development 'in a dish'. We also summarize some of the recently developed genetic tools that greatly facilitate the interrogation of gene function during hPSC differentiation. With the development of high-throughput screening technologies, hPSCs have the potential to revolutionize gene discovery in mammalian development.

  5. Induced pluripotent stem cell lines derived from human somatic cells.

    Science.gov (United States)

    Yu, Junying; Vodyanik, Maxim A; Smuga-Otto, Kim; Antosiewicz-Bourget, Jessica; Frane, Jennifer L; Tian, Shulan; Nie, Jeff; Jonsdottir, Gudrun A; Ruotti, Victor; Stewart, Ron; Slukvin, Igor I; Thomson, James A

    2007-12-21

    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.

  6. Genome engineering through CRISPR/Cas9 technology in the human germline and pluripotent stem cells.

    Science.gov (United States)

    Vassena, R; Heindryckx, B; Peco, R; Pennings, G; Raya, A; Sermon, K; Veiga, A

    2016-06-01

    With the recent development of CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 genome editing technology, the possibility to genetically manipulate the human germline (gametes and embryos) has become a distinct technical possibility. Although many technical challenges still need to be overcome in order to achieve adequate efficiency and precision of the technology in human embryos, the path leading to genome editing has never been simpler, more affordable, and widespread. In this narrative review we seek to understand the possible impact of CRISR/Cas9 technology on human reproduction from the technical and ethical point of view, and suggest a course of action for the scientific community. This non-systematic review was carried out using Medline articles in English, as well as technical documents from the Human Fertilisation and Embryology Authority and reports in the media. The technical possibilities of the CRISPR/Cas9 technology with regard to human reproduction are analysed based on results obtained in model systems such as large animals and laboratory rodents. Further, the possibility of CRISPR/Cas9 use in the context of human reproduction, to modify embryos, germline cells, and pluripotent stem cells is reviewed based on the authors' expert opinion. Finally, the possible uses and consequences of CRISPR/cas9 gene editing in reproduction are analysed from the ethical point of view. We identify critical technical and ethical issues that should deter from employing CRISPR/Cas9 based technologies in human reproduction until they are clarified. Overcoming the numerous technical limitations currently associated with CRISPR/Cas9 mediated editing of the human germline will depend on intensive research that needs to be transparent and widely disseminated. Rather than a call to a generalized moratorium, or banning, of this type of research, efforts should be placed on establishing an open, international, collaborative and regulated research

  7. Differentiation of human embryonic stem cells after transplantation in immune-deficient mice.

    Science.gov (United States)

    Przyborski, Stefan A

    2005-10-01

    Our current knowledge of how human tissues grow and develop is limited. We need to increase our understanding of tissue formation if we are to fully realize the potential of stem cells as a source of material for research into health and disease and possible therapeutic applications. Transplanted pluripotent human embryonic stem cells (hESCs) provide a potential system to model and investigate cell differentiation in humans. hESCs transplanted into immune-deficient mice form complex teratomas consisting of a range of differentiated somatic tissues, some of which appear highly organized and resemble structures normally identified in the embryo and adult. Analysis of such tumors may provide a unique opportunity to study organogenesis and lead to novel approaches in bioengineering and the growth of functioning structures composed of a range of alternative cell types. However, little has been done to characterize the developmental potential of hESCs after transplantation. This concise review presents evidence for the ability of hESCs to differentiate in vivo and highlights some of the prominent questions that need to be addressed if transplantation is to be used as a research tool to study hESC differentiation.

  8. Gene Coexpression and Evolutionary Conservation Analysis of the Human Preimplantation Embryos

    Directory of Open Access Journals (Sweden)

    Tiancheng Liu

    2015-01-01

    Full Text Available Evolutionary developmental biology (EVO-DEVO tries to decode evolutionary constraints on the stages of embryonic development. Two models—the “funnel-like” model and the “hourglass” model—have been proposed by investigators to illustrate the fluctuation of selective pressure on these stages. However, selective indices of stages corresponding to mammalian preimplantation embryonic development (PED were undetected in previous studies. Based on single cell RNA sequencing of stages during human PED, we used coexpression method to identify gene modules activated in each of these stages. Through measuring the evolutionary indices of gene modules belonging to each stage, we observed change pattern of selective constraints on PED for the first time. The selective pressure decreases from the zygote stage to the 4-cell stage and increases at the 8-cell stage and then decreases again from 8-cell stage to the late blastocyst stages. Previous EVO-DEVO studies concerning the whole embryo development neglected the fluctuation of selective pressure in these earlier stages, and the fluctuation was potentially correlated with events of earlier stages, such as zygote genome activation (ZGA. Such oscillation in an earlier stage would further affect models of the evolutionary constraints on whole embryo development. Therefore, these earlier stages should be measured intensively in future EVO-DEVO studies.

  9. Vascular potential of human pluripotent stem cells

    Science.gov (United States)

    Cardiovascular disease is the number one cause of death and disability in the US. Understanding the biological activity of stem and progenitor cells, and their ability to contribute to the repair, regeneration and remodeling of the heart and blood vessels affected by pathological processes is an ess...

  10. Biobanking human embryonic stem cell lines

    DEFF Research Database (Denmark)

    Holm, Søren

    2016-01-01

    are curiously absent from the particular stem cell banking policy discourse. This to some extent artificially isolates this discourse from the broader discussions about the flows of reproductive materials and tissues in modern society, and such isolation may lead to the interests of important actors being...

  11. Human amniotic fluid stem cells as a model for functional studies of genes involved in human genetic diseases or oncogenesis.

    Science.gov (United States)

    Rosner, Margit; Dolznig, Helmut; Schipany, Katharina; Mikula, Mario; Brandau, Oliver; Hengstschläger, Markus

    2011-09-01

    Besides their putative usage for therapies, stem cells are a promising tool for functional studies of genes involved in human genetic diseases or oncogenesis. For this purpose induced pluripotent stem (iPS) cells can be derived from patients harbouring specific mutations. In contrast to adult stem cells, iPS cells are pluripotent and can efficiently be grown in culture. However, iPS cells are modulated due to the ectopic induction of pluripotency, harbour other somatic mutations accumulated during the life span of the source cells, exhibit only imperfectly cleared epigenetic memory of the source cell, and are often genomically instable. In addition, iPS cells from patients only allow the investigation of mutations, which are not prenatally lethal. Embryonic stem (ES) cells have a high proliferation and differentiation potential, but raise ethical issues. Human embryos, which are not transferred in the course of in vitro fertilization, because of preimplantation genetic diagnosis of a genetic defect, are still rarely donated for the establishment of ES cell lines. In addition, their usage for studies on gene functions for oncogenesis is hampered by the fact the ES cells are already tumorigenic per se. In 2003 amniotic fluid stem (AFS) cells have been discovered, which meanwhile have been demonstrated to harbour the potential to differentiate into cells of all three germ layers. Monoclonal human AFS cell lines derived from amniocenteses have a high proliferative potential, are genomically stable and are not associated with ethical controversies. Worldwide amniocenteses are performed for routine human genetic diagnosis. We here discuss how generation and banking of monoclonal human AFS cell lines with specific chromosomal aberrations or monogenic disease mutations would allow to study the functional consequences of disease causing mutations. In addition, recently a protocol for efficient and highly reproducible siRNA-mediated long-term knockdown of endogenous gene

  12. Self-organized amniogenesis by human pluripotent stem cells in a biomimetic implantation-like niche

    Science.gov (United States)

    Shao, Yue; Taniguchi, Kenichiro; Gurdziel, Katherine; Townshend, Ryan F.; Xue, Xufeng; Yong, Koh Meng Aw; Sang, Jianming; Spence, Jason R.; Gumucio, Deborah L.; Fu, Jianping

    2017-04-01

    Amniogenesis--the development of amnion--is a critical developmental milestone for early human embryogenesis and successful pregnancy. However, human amniogenesis is poorly understood due to limited accessibility to peri-implantation embryos and a lack of in vitro models. Here we report an efficient biomaterial system to generate human amnion-like tissue in vitro through self-organized development of human pluripotent stem cells (hPSCs) in a bioengineered niche mimicking the in vivo implantation environment. We show that biophysical niche factors act as a switch to toggle hPSC self-renewal versus amniogenesis under self-renewal-permissive biochemical conditions. We identify a unique molecular signature of hPSC-derived amnion-like cells and show that endogenously activated BMP-SMAD signalling is required for the amnion-like tissue development by hPSCs. This study unveils the self-organizing and mechanosensitive nature of human amniogenesis and establishes the first hPSC-based model for investigating peri-implantation human amnion development, thereby helping advance human embryology and reproductive medicine.

  13. Human periodontal ligament stem cells repair mental nerve injury*

    Institute of Scientific and Technical Information of China (English)

    Bohan Li; Hun-Jong Jung; Soung-Min Kim; Myung-Jin Kim; Jeong Won Jahng; Jong-Ho Lee

    2013-01-01

    Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.

  14. Moderate ovarian stimulation does not increase the incidence of human embryo chromosomal abnormalities in in vitro fertilization cycles.

    Science.gov (United States)

    Labarta, Elena; Bosch, Ernesto; Alamá, Pilar; Rubio, Carmen; Rodrigo, Lorena; Pellicer, Antonio

    2012-10-01

    A high chromosomal abnormalities rate has been observed in human embryos derived from in vitro fertilization (IVF) treatments. The real incidence in natural cycles has been poorly studied, so whether this frequency may be induced by external factors, such as use of gonadotropins for ovarian stimulation, remains unknown. We conducted a prospective cohort study in a University-affiliated private infertility clinic with a comparison between unstimulated and stimulated ovarian cycles in the same women. Preimplantation genetic screening by fluorescence in situ hybridization was performed in all viable d 3 embryos. The primary objective was to compare the incidence of embryo chromosomal abnormalities in an unstimulated cycle and in an ulterior moderate ovarian stimulated cycle. Secondary outcome measures were embryo quality, blastocyst rate of biopsied embryos, number of normal blastocysts per donor, type of chromosomal abnormalities, and clinical outcome. One hundred eighty-five oocyte donors were initially recruited for the unstimulated cycle, and preimplantation genetic screening could be performed in 51 of them, showing 35.3% of embryo chromosomal abnormalities. Forty-six of them later completed a stimulated cycle. The sperm donor sample was the same for both cycles. The proportion of embryos displaying abnormalities in the unstimulated cycle was 34.8% (16 of 46), whereas it was 40.6% (123 of 303) in the stimulated cycle with risk difference=5.8 [95% confidence interval (CI)=-20.6-9.0], and relative risk=1.17 (95% CI=0.77-1.77) (P=0.45). When an intrasubject comparison was made, the abnormalities rate was 34.8% (95% CI=20.5-49.1) in the unstimulated cycle and 38.2% (95% CI=30.5-45.8) in the stimulated cycle [risk difference=3.4 (95% CI=-17.9-11.2); P=0.64]. No differences were observed for embryo quality and type of chromosomal abnormalities. Moderate ovarian stimulation in young normo-ovulatory women does not significantly increase the embryo aneuploidies rate in in

  15. Ethical Issues in Human Stem Cell Research%干细胞研究及其伦理学问题

    Institute of Scientific and Technical Information of China (English)

    翟晓梅

    2001-01-01

    The stem cell is a unique and essential cell type found in animals.When stem cells divide, some of the progeny mature into cells of a specific type , while others remain stem cells, ready to repair some of the everyday wear and tear undergone by our bodies. These stem cells are capable of continually reproducing themselves and serve to renew tissue throughout an individual's life. The most fundamental and extraordinary of the stem cells are found in the early-stage embryo. Scientific reports of the successful isolation and culture of the stem cells have offered hope of new cures for debilitating and even fatal illness, while at the same time renewing an important debate about the ethics of research involving human embryos and cadaveric fetal material.%干细胞是动物体内一种独特的基本细胞类型。干细胞分化时,有些成为特殊类型的细胞,另一些仍维持干细胞,准备替代机体衰老和损伤的细胞。这些干细胞本身能够复制,以供机体终生组织更新的需要。最基本的多能干细胞存在于早期胚胎中。科学家们成功分离和培育干细胞的报告,为退行性疾病和损伤甚至致命性疾病的治疗带来了新的希望。然而,与此同时也引起了世界范围的关于使用人类胚胎和死亡胎儿进行研究的伦理大争论。

  16. Identification of transcription factors that promote the differentiation of human pluripotent stem cells into lacrimal gland epithelium-like cells.

    Science.gov (United States)

    Hirayama, Masatoshi; Ko, Shigeru B H; Kawakita, Tetsuya; Akiyama, Tomohiko; Goparaju, Sravan K; Soma, Atsumi; Nakatake, Yuhki; Sakota, Miki; Chikazawa-Nohtomi, Nana; Shimmura, Shigeto; Tsubota, Kazuo; Ko, Minoru S H

    2017-01-01

    Dry eye disease is the most prevalent pathological condition in aging eyes. One potential therapeutic strategy is the transplantation of lacrimal glands, generated in vitro from pluripotent stem cells such as human embryonic stem cells, into patients. One of the preceding requirements is a method to differentiate human embryonic stem cells into lacrimal gland epithelium cells. As the first step for this approach, this study aims to identify a set of transcription factors whose overexpression can promote the differentiation of human embryonic stem cells into lacrimal gland epithelium-like cells. We performed microarray analyses of lacrimal glands and lacrimal glands-related organs obtained from mouse embryos and adults, and identified transcription factors enriched in lacrimal gland epithelium cells. We then transfected synthetic messenger RNAs encoding human orthologues of these transcription factors into human embryonic stem cells and examined whether the human embryonic stem cells differentiate into lacrimal gland epithelium-like cells by assessing cell morphology and marker gene expression. The microarray analysis of lacrimal glands tissues identified 16 transcription factors that were enriched in lacrimal gland epithelium cells. We focused on three of the transcription factors, because they are expressed in other glands such as salivary glands and are also known to be involved in the development of lacrimal glands. We tested the overexpression of various combinations of the three transcription factors and PAX6, which is an indispensable gene for lacrimal glands development, in human embryonic stem cells. Combining PAX6, SIX1, and FOXC1 caused significant changes in morphology, i.e., elongated cell shape and increased expression (both RNAs and proteins) of epithelial markers such as cytokeratin15, branching morphogenesis markers such as BARX2, and lacrimal glands markers such as aquaporin5 and lactoferrin. We identified a set of transcription factors enriched in

  17. Pluripotent stem cell-derived organoids: using principles of developmental biology to grow human tissues in a dish.

    Science.gov (United States)

    McCauley, Heather A; Wells, James M

    2017-03-15

    Pluripotent stem cell (PSC)-derived organoids are miniature, three-dimensional human tissues generated by the application of developmental biological principles to PSCs in vitro The approach to generate organoids uses a combination of directed differentiation, morphogenetic processes, and the intrinsically driven self-assembly of cells that mimics organogenesis in the developing embryo. The resulting organoids have remarkable cell type complexity, architecture and function similar to their in vivo counterparts. In the past five years, human PSC-derived organoids with components of all three germ layers have been generated, resulting in the establishment of a new human model system. Here, and in the accompanying poster, we provide an overview of how principles of developmental biology have been essential for generating human organoids in vitro, and how organoids are now being used as a primary research tool to investigate human developmental biology. © 2017. Published by The Company of Biologists Ltd.

  18. Human cytomegalovirus induces alteration of β-actin mRNA and microfilaments in human embryo fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    林茂芳; 魏国庆; 黄河; 蔡真

    2004-01-01

    Objective: To investigate the infection of human embryo fibroblast cell line HF cells by CMV as well as the effects of CMV on β-actin mRNA and microfilaments. Methods: HF cells shape was observed after the infection of CMV.RT-PCR assay was used to detect the mRNA expression of CMV immediate early (IE) gene, β-actin and GAPDH genes of HF cells infected by CMV. CMV particles and cell microfilaments were detected with electron microscope. Results: Shape of HF cell changed after the infection by CMV. HF cells infected by CMV could express IE mRNA and the expression of β-actin mRNA decreased in a time-and titer-dependent manner compared with the uninfected HF cells whose expression of GAPDH mRNA did not change much. CMV particles were found with electron microscope in the cells. Microfilaments were ruptured and shortened after the infection of CMV. Conclusion: CMV can not only infect human embryo fibroblast cells line HF cells and replicate in the cells, but can also affect the expression of β-actin mRNA and the microfilaments.

  19. Self-Organization of Stem Cell Colonies and of Early Mammalian Embryos: Recent Experiments Shed New Light on the Role of Autonomy vs. External Instructions in Basic Body Plan Development.

    Science.gov (United States)

    Denker, Hans-Werner

    2016-10-25

    "Organoids", i.e., complex structures that can develop when pluripotent or multipotent stem cells are maintained in three-dimensional cultures, have become a new area of interest in stem cell research. Hopes have grown that when focussing experimentally on the mechanisms behind this type of in vitro morphogenesis, research aiming at tissue and organ replacements can be boosted. Processes leading to the formation of organoids in vitro are now often addressed as self-organization, a term referring to the formation of complex tissue architecture in groups of cells without depending on specific instruction provided by other cells or tissues. The present article focuses on recent reports using the term self-organization in the context of studies on embryogenesis, specifically addressing pattern formation processes in human blastocysts attaching in vitro, or in colonies of pluripotent stem cells ("gastruloids"). These morphogenetic processes are of particular interest because, during development in vivo, they lead to basic body plan formation and individuation. Since improved methodologies like those employed by the cited authors became available, early embryonic pattern formation/self-organization appears to evolve now as a research topic of its own. This review discusses concepts concerning the involved mechanisms, focussing on autonomy of basic body plan development vs. dependence on external signals, as possibly provided by implantation in the uterus, and it addresses biological differences between an early mammalian embryo, e.g., a morula, and a cluster of pluripotent stem cells. It is concluded that, apart from being of considerable biological interest, the described type of research needs to be contemplated carefully with regard to ethical implications when performed with human cells.

  20. Stem Cells: A Renaissance in Human Biology Research.

    Science.gov (United States)

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-16

    The understanding of human biology and how it relates to that of other species represents an ancient quest. Limited access to human material, particularly during early development, has restricted researchers to only scratching the surface of this inherently challenging subject. Recent technological innovations, such as single cell "omics" and human stem cell derivation, have now greatly accelerated our ability to gain insights into uniquely human biology. The opportunities afforded to delve molecularly into scarce material and to model human embryogenesis and pathophysiological processes are leading to new insights of human development and are changing our understanding of disease and choice of therapy options.

  1. Mesenchymal Stem Cell Levels of Human Spinal Tissues.

    Science.gov (United States)

    Harris, Liam; Vangsness, C Thomas

    2017-09-06

    .: Systematic Review. .: The aim of this study was to investigate, quantify, compare and compile the various mesenchymal stem cell tissue sources within human spinal tissues to act as a compendium for clinical and research application. .: Recent years have seen a dramatic increase in academic and clinical understanding of human mesenchymal stem cells (MSCs). Previously limited to cells isolated from bone marrow, the past decade has illicited the characterization and isolation of human MSCs from adipose, bone marrow, synovium, muscle, periosteum, peripheral blood, umbilical cord, placenta and numerous other tissues. As researchers explore practical applications of cells in these tissues, the absolute levels of MSCs in specific spinal tissue will be critical to guide future research. .: The PubMED, MEDLINE, EMBASE and Cochrane databases were searched for articles relating to the harvest, characterization, isolation and quantification of human mesenchymal stem cells from spinal tissues. Selected articles were examined for relevant data, categorized according to type of spinal tissue, and when possible, standardized to facilitate comparisons between sites. .: Human mesenchymal stem cell levels varied widely between spinal tissues. Yields for Intervertebral disc demonstrated roughly 5% of viable cells to be positive for MSC surface markers. Cartilage endplate cells yielded 18,500- 61,875 cells/ 0.8 mm thick sample of cartilage end plate. Ligamentum flavum yielded 250,000- 500,000 cells per gram of tissue. Annulus fibrosus FACS treatment found 29% of cells positive for MSC marker Stro-1. Nucleus pulposus yielded mean tissue samples of 40,584-234,137 MSCs/gram of tissue. .: Numerous tissues within and surrounding the spine represent a consistent and reliable source for the harvest and isolation of human mesenchymal stem cells. Among the tissues of the spine, the annulus fibrosus and ligamentum flavum each offer considerable levels of mesenchymal stem cells, and may

  2. Human embryonic stem cell research: ethical and legal issues.

    Science.gov (United States)

    Robertson, J A

    2001-01-01

    The use of human embryonic stem cells to replace damaged cells and tissues promises future hope for the treatment of many diseases. However, many countries now face complex ethical and legal questions as a result of the research needed to develop these cell-replacement therapies. The challenge that must be met is how to permit research on human embryonic tissue to occur while maintaining respect for human life generally.

  3. Statement on Human Cloning

    Science.gov (United States)

    ... ban on efforts to implant a human cloned embryo for the purpose of reproduction. The scientific evidence ... stem cell research, including the use of nuclear transplantation techniques (also known as research or therapeutic cloning), ...

  4. Embryonic catalase protects against ethanol embryopathies in acatalasemic mice and transgenic human catalase-expressing mice in embryo culture

    Energy Technology Data Exchange (ETDEWEB)

    Miller-Pinsler, Lutfiya [Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada); Wells, Peter G., E-mail: pg.wells@utoronto.ca [Division of Biomolecular Sciences, Faculty of Pharmacy, University of Toronto, Toronto, Ontario (Canada); Department of Pharmacology and Toxicology, Faculty of Medicine, University of Toronto, Toronto, Ontario (Canada)

    2015-09-15

    Reactive oxygen species (ROS) have been implicated in the mechanism of ethanol (EtOH) teratogenicity, but the protective role of the embryonic antioxidative enzyme catalase is unclear, as embryonic activity is only about 5% of maternal levels. We addressed this question in a whole embryo culture model. C57BL/6 mouse embryos expressing human catalase (hCat) or their wild-type (C57BL/6 WT) controls, and C3Ga.Cg-Cat{sup b}/J catalase-deficient, acatalasemic (aCat) mouse embryos or their wild-type C3HeB/FeJ (C3H WT) controls, were explanted on gestational day (GD) 9 (plug = GD 1), exposed for 24 h to 2 or 4 mg/mL EtOH or vehicle, and evaluated for functional and morphological changes. hCat and C57BL/6 WT vehicle-exposed embryos developed normally, while EtOH was embryopathic in C57BL/6 WT embryos, evidenced by decreases in anterior neuropore closure, somites developed, turning and head length, whereas hCat embryos were protected (p < 0.001). Maternal pretreatment of C57BL/6 WT dams with 50 kU/kg PEG-catalase (PEG-cat) 8 h prior to embryo culture, which increases embryonic catalase activity, blocked all EtOH embryopathies (p < 0.001). Vehicle-exposed aCat mouse embryos had lower yolk sac diameters compared to WT controls, suggesting that endogenous ROS are embryopathic. EtOH was more embryopathic in aCat embryos than WT controls, evidenced by reduced head length and somite development (p < 0.01), and trends for reduced anterior neuropore closure, turning and crown–rump length. Maternal pretreatment of aCat dams with PEG-Cat blocked all EtOH embryopathies (p < 0.05). These data suggest that embryonic catalase is a determinant of risk for EtOH embryopathies. - Highlights: • Ethanol (EtOH) exposure causes structural embryopathies in embryo culture. • Genetically enhanced catalase (hCat) protects against EtOH embryopathies. • Genetically deficient catalase (aCat) exacerbates EtOH embryopathies. • Embryonic catalase is developmentally important. • Et

  5. In vitro development of donated frozen-thawed human embryos in a prototype static microfluidic device: a randomized controlled trial

    NARCIS (Netherlands)

    Kieslinger, Dorit C.; Hao, Zhenxia; Vergouw, Carlijn G.; Kostelijk, Elisabeth H.; Lambalk, Cornelis B.; Le Gac, Séverine

    2015-01-01

    Objective: To compare the development of human embryos in microfluidic devices with culture in standard microdrop dishes, both under static conditions. Design: Prospective randomized controlled trial. Setting: In vitro fertilization laboratory. Patient(s): One hundred eighteen donated frozen-t

  6. Analysis of Intracellular Calcium Signaling in Human Embryonic Stem Cells.

    Science.gov (United States)

    Péntek, Adrienn; Pászty, Katalin; Apáti, Ágota

    2016-01-01

    Measurement of changes in intracellular calcium concentration is one of the most common and useful tools for studying signal transduction pathways or cellular responses in basic research and drug screening purposes as well. Increasing number of such applications using human pluripotent stem cells and their derivatives requires development of calcium signal measurements for this special cell type. Here we describe a modified protocol for analysis of calcium signaling events in human embryonic stem cells, which can be used for other pluripotent cell types (such as iPSC) or their differentiated offspring as well.

  7. [In vitro strategies for human gametes production from stem cells].

    Science.gov (United States)

    Tosca, Lucie; Courtot, Anne-Marie; Bennaceur-Griscelli, Annelise; Tachdjian, Gérard

    2011-10-01

    Embryonic stem cells (ESC) are self-renewal and pluripotent cells that are able to differentiate in vitro into several cell types in favourable conditions. Technical protocols for in vitro gametes production have been developed in mice and human species. The functionality of such differentiated cells is not always analysed and an early meiotic arrest is a current observation. These kinds of experimentations have also been tested from human induced pluripotent stem cells (IPSC). However, differentiation ends shortly at the primordial germ cell stage.

  8. Modelling Neurodegenerative Diseases Using Human Pluripotent Stem Cells

    DEFF Research Database (Denmark)

    Hall, Vanessa J.

    2016-01-01

    Neurodegenerative diseases are being modelled in-vitro using human patient-specific, induced pluripotent stem cells and transgenic embryonic stem cells to determine more about disease mechanisms, as well as to discover new treatments for patients. Current research in modelling Alzheimer’s disease......, frontotemporal dementia and Parkinson’s disease using pluripotent stem cells is described, along with the advent of gene-editing, which has been the complimentary tool for the field. Current methods used to model these diseases are predominantly dependent on 2D cell culture methods. Outcomes reveal that only...... that includes studying more complex 3D cell cultures, as well as accelerating aging of the neurons, may help to yield stronger phenotypes in the cultured cells. Thus, the use and application of pluripotent stem cells for modelling disease have already shown to be a powerful approach for discovering more about...

  9. Reprogramming of adult human neural stem cells into induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    XIE Li-qian; SUN Hua-ping; WANG Tian; TANG Hai-liang; WANG Pu; ZHU Jian-hong; YAO Zheng-wei

    2013-01-01

    Background Since an effective method for generating induced pluripotent stem cells (iPSCs) from human neural stem cells (hNSCs) can offer us a promising tool for studying brain diseases,here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors.Methods NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients.When combined with four factors (OCT3/4,SOX2,KLF4,and c-MYC),iPSCs colonies were successfully obtained.Results Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties,which include the ability to differentiate into all three germ layers both in vitro and in vivo.Conclusion Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.

  10. [Yes to research, no to utilization? Medical, pharmacological and toxicological utilization of human embryonic stem cells from an ethical point of view].

    Science.gov (United States)

    Kress, H

    2008-09-01

    In exceptional cases, the German Stem Cell Act allows research on human embryonic stem cells. However, it does not allow the implementation of the research results if this in turn requires the use of further embryonic stem cell lines. It has, in the meantime, transpired that such research results could be of concrete use. Thus, in the distant future, it could be used in the clinical treatment of patients. Already in the nearer future the use of human embryonic stem cell lines can be envisaged for both the development and testing of medicines as well as in the field of toxicology. To this end, research concerning embryo toxicity and neurotoxicity is ground-breaking. The toxicological and pharmacological use of human embryonic stem cell lines should serve the protection of human health as well as the safe and reliable use of medicines. In addition, animal experiments could be reduced, which is desirable from a point of view of animal protection ethics. Since research on human embryonic stem cell lines is actually permitted in Germany, the use of the respective research results should be allowed all the more. This follows from the basic human right to health protection and health care. Legal ambiguities, which still exist in this respect, should be removed.

  11. Expression pattern of pluripotent markers in different embryonic developmental stages of buffalo (Bubalus bubalis) embryos and putative embryonic stem cells generated by parthenogenetic activation.

    Science.gov (United States)

    Singh, Karn P; Kaushik, Ramakant; Garg, Veena; Sharma, Ruchi; George, Aman; Singh, Manoj K; Manik, Radhey S; Palta, Prabhat; Singla, Suresh K; Chauhan, Manmohan S

    2012-12-01

    In this study, we describe the production of buffalo parthenogenetic blastocysts and subsequent isolation of parthenogenetic embryonic stem cell (PGESC)-like cells. PGESC colonies exhibited dome-shaped morphology and were clearly distinguishable from the feeder layer cells. Different stages of development of parthenogenetic embryos and derived embryonic stem cell (ESC)-like cells expressed key ESC-specific markers, including OCT-4, NANOG, SOX-2, FOXD3, REX-1, STAT-3, TELOMERASE, NUCLEOSTEMIN, and cMYC. Immunofluorescence-based studies revealed that the PGESCs were positive for surface-based pluripotent markers, viz., SSEA-3, SSEA-4, TRA 1-80, TRA 1-60, CD-9, and CD-90 and exhibited high alkaline phosphatase (ALP) activity. PGEC cell-like cells formed embryoid body (EB)-like structures in hanging drop cultures and when cultured for extended period of time spontaneously differentiated into derivatives of three embryonic germ layers as confirmed by RT-PCR for ectodermal (CYTOKERATIN8, NF-68), mesodermal (MSX1, BMP-4, ASA), and endodermal markers (AFP, HNF-4, GATA-4). Differentiation of PGESCs toward the neuronal lineage was successfully directed by supplementation of serum-containing media with retinoic acid. Our results indicate that the isolated ESC-like cells from parthenogenetic blastocyst hold properties of ESCs and express markers of pluripotency. The pluripotency markers were also expressed by early cleavage-stage of buffalo embryos.

  12. Very Small Embryonic-Like Stem Cells: A Potential Developmental Link Between Germinal Lineage and Hematopoiesis in Humans.

    Science.gov (United States)

    Virant-Klun, Irma

    2016-01-15

    It has been suggested that hematopoietic stem/progenitor cells (HSPCs) could become specified from a population of migrating primordial germ cells (PGCs), precursors of gametes, during embryogenesis. Some recent experimental data demonstrated that the cell population that is usually considered to be PGCs, moving toward the gonadal ridges of an embryo, contains a subset of cells coexpressing several germ cell and hematopoietic markers and possessing hematopoietic activity. Experimental data showed that bone morphogenetic protein 4 (BMP4) generates PGCs from mouse bone marrow-derived pluripotent stem cells. Interestingly, functional reproductive hormone receptors have been identified in HSPCs, thus indicating their potential role in reproductive function. Several reports have demonstrated fertility restoration and germ cell generation after bone marrow transplantation in both animal models and humans. A potential link between HSPCs and germinal lineage might be represented by very small embryonic-like stem cells (VSELs), which have been found in adult human bone marrow, peripheral blood, and umbilical cord blood, express a specific pattern of pluripotency, germinal lineage, and hematopoiesis, and are proposed to persist in adult tissues and organs from the embryonic period of life. Stem cell populations, similar to VSELs, expressing several genes related to pluripotency and germinal lineage, especially to PGCs, have been discovered in adult human reproductive organs, ovaries and testicles, and were related to primitive germ cell-like cell development in vitro, thus supporting the idea of VSELs as a potential link between germinal lineage and hematopoiesis.

  13. Putative porcine embryonic stem cell lines derived from aggregated four-celled cloned embryos produced by oocyte bisection cloning.

    Science.gov (United States)

    Siriboon, Chawalit; Lin, Yu-Hsuan; Kere, Michel; Chen, Chun-Da; Chen, Lih-Ren; Chen, Chien-Hong; Tu, Ching-Fu; Lo, Neng-Wen; Ju, Jyh-Cherng

    2015-01-01

    We attempted to isolate ES cell lines using inner cell masses from high-quality cloned porcine blastocysts. After being seeded onto feeders, embryos had better (P cloned embryos (62.8, 42.6 and 12.8% vs. 76.2, 55.2 and 26.2%, respectively) compared to the non-aggregated group (41.6, 23.4 and 3.9%). Effects of feeder types (STO vs. MEF) and serum sources (FBS vs. KSR) on extraction of cloned embryo-derived porcine ES cells were examined. More (17.1%) ntES cell lines over Passage 3 were generated in the MEF/KSR group. However, ntES cells cultured in KSR-supplemented medium had a low proliferation rate with defective morphology, and eventually underwent differentiation or apoptosis subsequently. Approximately 26.1, 22.7 and 35.7% of primary colonies were formed after plating embryos in DMEM, DMEM/F12 and α-MEM media, respectively. Survival rates of ntES cells cultured in α-MEM, DMEM and DMEM/F12 were 16.7, 4.3 and 6.8%, respectively (P > 0.05). We further examined the beneficial effect of TSA treatment of 3× aggregated cloned embryos on establishment of ntES cell lines. Primary colony numbers and survival rates of ntES cells beyond passage 3 were higher (P cloned embryos produced by embryo aggregation, and optimized the ES cell culture system suitable for establishing and maintaining ntES cell lines in undifferentiated state.

  14. Hematopoietic development from human induced pluripotent stem cells.

    Science.gov (United States)

    Lengerke, Claudia; Grauer, Matthias; Niebuhr, Nina I; Riedt, Tamara; Kanz, Lothar; Park, In-Hyun; Daley, George Q

    2009-09-01

    A decade of research on human embryonic stem cells (ESC) has paved the way for the discovery of alternative approaches to generating pluripotent stem cells. Combinatorial overexpression of a limited number of proteins linked to pluripotency in ESC was recently found to reprogram differentiated somatic cells back to a pluripotent state, enabling the derivation of isogenic (patient-specific) pluripotent stem cell lines. Current research is focusing on improving reprogramming protocols (e.g., circumventing the use of retroviral technology and oncoproteins), and on methods for differentiation into transplantable tissues of interest. In mouse ESC, we have previously shown that the embryonic morphogens BMP4 and Wnt3a direct blood formation via activation of Cdx and Hox genes. Ectopic expression of Cdx4 and HoxB4 enables the generation of mouse ESC-derived hematopoietic stem cells (HSC) capable of multilineage reconstitution of lethally irradiated adult mice. Here, we explore hematopoietic development from human induced pluripotent stem (iPS) cells generated in our laboratory. Our data show robust differentiation of iPS cells to mesoderm and to blood lineages, as shown by generation of CD34(+)CD45(+) cells, hematopoietic colony activity, and gene expression data, and suggest conservation of blood patterning pathways between mouse and human hematopoietic development.

  15. Mapping the stem cell state: eight novel human embryonic stem and embryonal carcinoma cell antibodies

    DEFF Research Database (Denmark)

    Wright, A; Andrews, N; Bardsley, K

    2011-01-01

    The antigenic profile of human embryonic stem (ES) and embryonal carcinoma (EC) cells has served as a key element of their characterization, with a common panel of surface and intracellular markers now widely used. Such markers have been used to identify cells within the 'undifferentiated state...

  16. Human dental pulp stem cells: Applications in future regenerative medicine.

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-06-26

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine.

  17. Generation of human-induced pluripotent stem cells.

    Science.gov (United States)

    Park, In-Hyun; Lerou, Paul H; Zhao, Rui; Huo, Hongguang; Daley, George Q

    2008-01-01

    Pluripotent cells, such as embryonic stem cells, are invaluable tools for research and can potentially serve as a source of cell- and tissue-replacement therapy. Rejection after transplantation of cells and tissue derived from embryonic stem cells is a significant obstacle to their clinical use. Recently, human somatic cells 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. Human iPS cells are a potential source of patient-specific pluripotent stem cells that would bypass immune rejection. iPS cells can also be used to study diseases for which there are no adequate human in vitro or animal models. In this protocol, we describe how to establish primary human fibroblasts lines and how to derive iPS cells by retroviral transduction of reprogramming factors. Overall, it takes 2 months to complete reprogramming human primary fibroblasts starting from biopsy.

  18. Insights in spatio-temporal characterization of human fetal neural stem cells.

    Science.gov (United States)

    Martín-Ibáñez, Raquel; Guardia, Inés; Pardo, Mónica; Herranz, Cristina; Zietlow, Rike; Vinh, Ngoc-Nga; Rosser, Anne; Canals, Josep M

    2017-05-01

    Primary human fetal cells have been used in clinical trials of cell replacement therapy for the treatment of neurodegenerative disorders such as Huntington's disease (HD). However, human fetal primary cells are scarce and difficult to work with and so a renewable source of cells is sought. Human fetal neural stem cells (hfNSCs) can be generated from human fetal tissue, but little is known about the differences between hfNSCs obtained from different developmental stages and brain areas. In the present work we characterized hfNSCs, grown as neurospheres, obtained from three developmental stages: 4-5, 6-7 and 8-9weeks post conception (wpc) and four brain areas: forebrain, cortex, whole ganglionic eminence (WGE) and cerebellum. We observed that, as fetal brain development proceeds, the number of neural precursors is diminished and post-mitotic cells are increased. In turn, primary cells obtained from older embryos are more sensitive to the dissociation process, their viability is diminished and they present lower proliferation ratios compared to younger embryos. However, independently of the developmental stage of derivation proliferation ratios were very low in all cases. Improvements in the expansion rates were achieved by mechanical, instead of enzymatic, dissociation of neurospheres but not by changes in the seeding densities. Regardless of the developmental stage, neurosphere cultures presented large variability in the viability and proliferation rates during the initial 3-4 passages, but stabilized achieving significant expansion rates at passage 5 to 6. This was true also for all brain regions except cerebellar derived cultures that did not expand. Interestingly, the brain region of hfNSC derivation influences the expansion potential, being forebrain, cortex and WGE derived cells the most expandable compared to cerebellar. Short term expansion partially compromised the regional identity of cortical but not WGE cultures. Nevertheless, both expanded cultures were

  19. Culture systems: embryo density.

    Science.gov (United States)

    Reed, Michael L

    2012-01-01

    Embryo density is defined as the embryo-to-volume ratio achieved during in vitro culture; in other words, it is the number of embryos in a defined volume of culture medium. The same density can be achieved by manipulating either the number of embryos in a given volume of medium, or manipulating the volume of the medium for a given number of embryos: for example, a microdrop with five embryos in a 50 μl volume under oil has the same embryo-to-volume ratio (1:10 μl) as a microdrop with one embryo in a 10 μl volume under oil (1:10 μl). Increased embryo density can improve mammalian embryo development in vitro; however, the mechanism(s) responsible for this effect may be different with respect to which method is used to increase embryo density.Standard, flat sterile plastic petri dishes are the most common, traditional platform for embryo culture. Microdrops under a mineral oil overlay can be prepared to control embryo density, but it is critical that dish preparation is consistent, where appropriate techniques are applied to prevent microdrop dehydration during preparation, and results of any data collection are reliable, and repeatable. There are newer dishes available from several manufacturers that are specifically designed for embryo culture; most are readily available for use with human embryos. The concept behind these newer dishes relies on fabrication of conical and smaller volume wells into the dish design, so that embryos rest at the lowest point in the wells, and where putative embryotrophic factors may concentrate.Embryo density is not usually considered by the embryologist as a technique in and of itself; rather, the decision to culture embryos in groups or individually is protocol-driven, and is based more on convenience or the need to collect data on individual embryos. Embryo density can be controlled, and as such, it can be utilized as a simple, yet effective tool to improve in vitro development of human embryos.

  20. Are human dental papilla-derived stem cell and human brain-derived neural stem cell transplantations suitable for treatment of Parkinson's disease?

    Science.gov (United States)

    Yoon, Hyung Ho; Min, Joongkee; Shin, Nari; Kim, Yong Hwan; Kim, Jin-Mo; Hwang, Yu-Shik; Suh, Jun-Kyo Francis; Hwang, Onyou; Jeon, Sang Ryong

    2013-05-05

    Transplantation of neural stem cells has been reported as a possible approach for replacing impaired dopaminergic neurons. In this study, we tested the efficacy of early-stage human dental papilla-derived stem cells and human brain-derived neural stem cells in rat models of 6-hydroxydopamine-induced Parkinson's disease. Rats received a unilateral injection of 6-hydroxydopamine into right medial forebrain bundle, followed 3 weeks later by injections of PBS, early-stage human dental papilla-derived stem cells, or human brain-derived neural stem cells into the ipsilateral striatum. All of the rats in the human dental papilla-derived stem cell group died from tumor formation at around 2 weeks following cell transplantation. Postmortem examinations revealed homogeneous malignant tumors in the striatum of the human dental papilla-derived stem cell group. Stepping tests revealed that human brain-derived neural stem cell transplantation did not improve motor dysfunction. In apomorphine-induced rotation tests, neither the human brain-derived neural stem cell group nor the control groups (PBS injection) demonstrated significant changes. Glucose metabolism in the lesioned side of striatum was reduced by human brain-derived neural stem cell transplantation. [(18)F]-FP-CIT PET scans in the striatum did not demonstrate a significant increase in the human brain-derived neural stem cell group. Tyrosine hydroxylase (dopaminergic neuronal marker) staining and G protein-activated inward rectifier potassium channel 2 (A9 dopaminergic neuronal marker) were positive in the lesioned side of striatum in the human brain-derived neural stem cell group. The use of early-stage human dental papilla-derived stem cells confirmed its tendency to form tumors. Human brain-derived neural stem cells could be partially differentiated into dopaminergic neurons, but they did not secrete dopamine.

  1. Are human dental papilla-derived stem cell and human brain-derived neural stem cell transplantations suitable for treatment of Parkinson's disease?

    Institute of Scientific and Technical Information of China (English)

    Hyung Ho Yoon; Joongkee Min; Nari Shin; Yong Hwan Kim; Jin-Mo Kim; Yu-Shik Hwang; Jun-Kyo Francis Suh; Onyou Hwang; Sang Ryong Jeon

    2013-01-01

    Transplantation of neural stem cells has been reported as a possible approach for replacing impaired dopaminergic neurons. In this study, we tested the efficacy of early-stage human dental papilla-derived stem cells and human brain-derived neural stem cells in rat models of 6-hydroxydopamine-induced Parkinson's disease. Rats received a unilateral injection of 6-hydroxydopamine into right medial forebrain bundle, followed 3 weeks later by injections of PBS, early-stage human dental papilla-derived stem cells, or human brain-derived neural stem cells into the ipsilateral striatum. All of the rats in the human dental papilla-derived stem cell group died from tumor formation at around 2 weeks following cell transplantation. Postmortem examinations revealed homogeneous malignant tumors in the striatum of the human dental papilla-derived stem cell group. Stepping tests revealed that human brain-derived neural stem cell transplantation did not improve motor dysfunction. In apomorphine-induced rotation tests, neither the human brain-derived neural stem cell group nor the control groups (PBS injection) demonstrated significant changes. Glucose metabolism in the lesioned side of striatum was reduced by human brain-derived neural stem cell transplantation. [18 F]-FP-CIT PET scans in the striatum did not demonstrate a significant increase in the human brain-derived neural stem cell group. Tyrosine hydroxylase (dopaminergic neuronal marker) staining and G protein-activated inward rectifier potassium channel 2 (A9 dopaminergic neuronal marker) were positive in the lesioned side of striatum in the human brain-derived neural stem cell group. The use of early-stage human dental papilla-derived stem cells confirmed its tendency to form tumors. Human brain-derived neural stem cells could be partially differentiated into dopaminergic neurons, but they did not secrete dopamine.

  2. Nuclear Nox4 Role in Stemness Power of Human Amniotic Fluid Stem Cells

    Directory of Open Access Journals (Sweden)

    Tullia Maraldi

    2015-01-01

    Full Text Available Human amniotic fluid stem cells (AFSC are an attractive source for cell therapy due to their multilineage differentiation potential and accessibility advantages. However the clinical application of human stem cells largely depends on their capacity to expand in vitro, since there is an extensive donor-to-donor heterogeneity. Reactive oxygen species (ROS and cellular oxidative stress are involved in many physiological and pathophysiological processes of stem cells, including pluripotency, proliferation, differentiation, and stress resistance. The mode of action of ROS is also dependent on the localization of their target molecules. Thus, the modifications induced by ROS can be separated depending on the cellular compartments they affect. NAD(PH oxidase family, particularly Nox4, has been known to produce ROS in the nucleus. In the present study we show that Nox4 nuclear expression (nNox4 depends on the donor and it correlates with the expression of transcription factors involved in stemness regulation, such as Oct4, SSEA-4, and Sox2. Moreover nNox4 is linked with the nuclear localization of redox sensitive transcription factors, as Nrf2 and NF-κB, and with the differentiation potential. Taken together, these results suggest that nNox4 regulation may have important effects in stem cell capability through modulation of transcription factors and DNA damage.

  3. Molecular Mechanisms Regulating Impaired Neurogenesis of Fragile X Syndrome Human Embryonic Stem Cells

    Science.gov (United States)

    Telias, Michael; Mayshar, Yoav; Amit, Ami

    2015-01-01

    Fragile X syndrome (FXS) is the most common form of inherited cognitive impairment. It is caused by developmental inactivation of the FMR1 gene and the absence of its encoded protein FMRP, which plays pivotal roles in brain development and function. In FXS embryos with full FMR1 mutation, FMRP is expressed during early embryogenesis and is gradually downregulated at the third trimester of pregnancy. FX-human embryonic stem cells (FX-hESCs), derived from FX human blastocysts, demonstrate the same pattern of developmentally regulated FMR1 inactivation when subjected to in vitro neural differentiation (IVND). In this study, we used this in vitro human platform to explore the molecular mechanisms downstream to FMRP in the context of early human embryonic neurogenesis. Our results show a novel role for the SOX superfamily of transcription factors, specifically for SOX2 and SOX9, which could explain the reduced and delayed neurogenesis observed in FX cells. In addition, we assess in this study the “GSK3β theory of FXS” for the first time in a human-based model. We found no evidence for a pathological increase in GSK3β protein levels upon cellular loss of FMRP, in contrast to what was found in the brain of Fmr1 knockout mice. Our study adds novel data on potential downstream targets of FMRP and highlights the importance of the FX-hESC IVND system. PMID:26393806

  4. Transfer of human frozen-thawed embryos with further cleavage during culture increases pregnancy rates

    Directory of Open Access Journals (Sweden)

    Bharat V Joshi

    2010-01-01

    Full Text Available Aim: To compare the pregnancy rate following transfer of frozen-thawed embryos with or without overnight culture after thawing. Settings and Design: This is a retrospective analysis of frozen-thawed embryo transfer (FET cycles performed between January 2006 and December 2008. Materials and Methods: Out of 518 thaw cycles, 504 resulted in embryo transfers (ETs. Of the total FET cycles, 415 were performed after an overnight culture of embryos (group A; and in 89 cycles, ET was performed within 2 hours of embryo thawing (group B. Statistical Analysis: The data were statistically analyzed using chi-square test. Results: We observed that with FET, women ≤30 years of age had a significantly higher (P=0.003 pregnancy rate (PR=28.9% as compared to women >30 years of age (17.5%. A significantly higher (P<0.001FNx08 pregnancy rate was also observed in women receiving 3 frozen-thawed embryos (29% as compared to those who received less than 3 embryos (10.7%. The difference in PR between group A (PR=24.3% and group B (PR=20.3% was not statistically significant. However, within group A, ET with cleaved embryos showed significantly ( P≤0.01 higher pregnancy rate compared to the uncleaved embryos, depending on the number of cleaved embryos transferred. Conclusion: No significant difference was noticed between FETs made with transfer of embryos with overnight culture and those without culture. However, within the cultured group, transfer of embryos cleaved during overnight culture gave significantly higher PR than transfers without any cleavage.

  5. Functional analysis of human hematopoietic stem cell gene expression using zebrafish.

    Directory of Open Access Journals (Sweden)

    Craig E Eckfeldt

    2005-08-01

    Full Text Available Although several reports have characterized the hematopoietic stem cell (HSC transcriptome, the roles of HSC-specific genes in hematopoiesis remain elusive. To identify candidate regulators of HSC fate decisions, we compared the transcriptome of human umbilical cord blood and bone marrow (CD34+(CD33-(CD38-Rho(lo(c-kit+ cells, enriched for hematopoietic stem/progenitor cells with (CD34+(CD33-(CD38-Rho(hi cells, enriched in committed progenitors. We identified 277 differentially expressed transcripts conserved in these ontogenically distinct cell sources. We next performed a morpholino antisense oligonucleotide (MO-based functional screen in zebrafish to determine the hematopoietic function of 61 genes that had no previously known function in HSC biology and for which a likely zebrafish ortholog could be identified. MO knock down of 14/61 (23% of the differentially expressed transcripts resulted in hematopoietic defects in developing zebrafish embryos, as demonstrated by altered levels of circulating blood cells at 30 and 48 h postfertilization and subsequently confirmed by quantitative RT-PCR for erythroid-specific hbae1 and myeloid-specific lcp1 transcripts. Recapitulating the knockdown phenotype using a second MO of independent sequence, absence of the phenotype using a mismatched MO sequence, and rescue of the phenotype by cDNA-based overexpression of the targeted transcript for zebrafish spry4 confirmed the specificity of MO targeting in this system. Further characterization of the spry4-deficient zebrafish embryos demonstrated that hematopoietic defects were not due to more widespread defects in the mesodermal development, and therefore represented primary defects in HSC specification, proliferation, and/or differentiation. Overall, this high-throughput screen for the functional validation of differentially expressed genes using a zebrafish model of hematopoiesis represents a major step toward obtaining meaningful information from global

  6. The nuclear mitotic apparatus (NuMA) protein: localization and dynamics in human oocytes, fertilization and early embryos.

    Science.gov (United States)

    Alvarez Sedó, Cristian; Schatten, Heide; Combelles, Catherine M; Rawe, Vanesa Y

    2011-06-01

    The oocyte's meiotic spindle is a dynamic structure that relies on microtubule organization and regulation by centrosomes. Disorganization of centrosomal proteins, including the nuclear mitotic apparatus (NuMA) protein and the molecular motor complex dynein/dynactin, can lead to chromosomal instability and developmental abnormalities. The present study reports the distribution and function of these proteins in human oocytes, zygotes and early embryos. A total of 239 oocytes, 90 zygotes and discarded embryos were fixed and analyzed with confocal microscopy for NuMA and dynactin distribution together with microtubules and chromatin. Microtubule-associated dynein-dependent transport functions were explored by inhibiting phosphatase and ATPase activity with sodium-orthovanadate (SOV). At germinal vesicle (GV) stages, NuMA was dispersed across the nucleoplasm. After GV breaks down, NuMA became cytoplasmic before localizing at the spindle poles in metaphase I and II oocytes. Aberrant NuMA localization patterns were found during oocyte in vitro maturation. After fertilization, normal and abnormal pronuclear stage zygotes and embryos displayed translocation of NuMA to interphase nuclei. SOV treatment for up to 2 h induced lower maturation rates with chromosomal scattering and ectopic localization of NuMA. Accurate distribution of NuMA is important for oocyte maturation, zygote and embryo development in humans. Proper assembly of NuMA is likely necessary for bipolar spindle organization and human oocyte developmental competence.

  7. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Armin Arshi, Yasuhiro Nakashima, Haruko Nakano, Sarayoot Eaimkhong, Denis Evseenko, Jason Reed, Adam Z Stieg, James K Gimzewski and Atsushi Nakano

    2013-01-01

    Full Text Available While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES cells providing an endless reservoir. In addition to secreted factors and cell–cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

  8. Rigid microenvironments promote cardiac differentiation of mouse and human embryonic stem cells

    Science.gov (United States)

    Arshi, Armin; Nakashima, Yasuhiro; Nakano, Haruko; Eaimkhong, Sarayoot; Evseenko, Denis; Reed, Jason; Stieg, Adam Z.; Gimzewski, James K.; Nakano, Atsushi

    2013-04-01

    While adult heart muscle is the least regenerative of tissues, embryonic cardiomyocytes are proliferative, with embryonic stem (ES) cells providing an endless reservoir. In addition to secreted factors and cell-cell interactions, the extracellular microenvironment has been shown to play an important role in stem cell lineage specification, and understanding how scaffold elasticity influences cardiac differentiation is crucial to cardiac tissue engineering. Though previous studies have analyzed the role of matrix elasticity on the function of differentiated cardiomyocytes, whether it affects the induction of cardiomyocytes from pluripotent stem cells is poorly understood. Here, we examine the role of matrix rigidity on cardiac differentiation using mouse and human ES cells. Culture on polydimethylsiloxane (PDMS) substrates of varied monomer-to-crosslinker ratios revealed that rigid extracellular matrices promote a higher yield of de novo cardiomyocytes from undifferentiated ES cells. Using a genetically modified ES system that allows us to purify differentiated cardiomyocytes by drug selection, we demonstrate that rigid environments induce higher cardiac troponin T expression, beating rate of foci, and expression ratio of adult α- to fetal β- myosin heavy chain in a purified cardiac population. M-mode and mechanical interferometry image analyses demonstrate that these ES-derived cardiomyocytes display functional maturity and synchronization of beating when co-cultured with neonatal cardiomyocytes harvested from a developing embryo. Together, these data identify matrix stiffness as an independent factor that instructs not only the maturation of already differentiated cardiomyocytes but also the induction and proliferation of cardiomyocytes from undifferentiated progenitors. Manipulation of the stiffness will help direct the production of functional cardiomyocytes en masse from stem cells for regenerative medicine purposes.

  9. Dissecting the oncogenic and tumorigenic potential of differentiated human induced pluripotent stem cells and human embryonic stem cells.

    Science.gov (United States)

    Ghosh, Zhumur; Huang, Mei; Hu, Shijun; Wilson, Kitchener D; Dey, Devaveena; Wu, Joseph C

    2011-07-15

    Pluripotent stem cells, both human embryonic stem cells (hESC) and human-induced pluripotent stem cells (hiPSC), can give rise to multiple cell types and hence have tremendous potential for regenerative therapies. However, the tumorigenic potential of these cells remains a great concern, as reflected in the formation of teratomas by transplanted pluripotent cells. In clinical practice, most pluripotent cells will be differentiated into useful therapeutic cell types such as neuronal, cardiac, or endothelial cells prior to human transplantation, drastically reducing their tumorigenic potential. Our work investigated the extent to which these differentiated stem cell derivatives are truly devoid of oncogenic potential. In this study, we analyzed the gene expression patterns from three sets of hiPSC- and hESC-derivatives and the corresponding primary cells, and compared their transcriptomes with those of five different types of cancer. Our analysis revealed a significant gene expression overlap of the hiPSC- and hESC-derivatives with cancer, whereas the corresponding primary cells showed minimum overlap. Real-time quantitative PCR analysis of a set of cancer-related genes (selected on the basis of rigorous functional and pathway analyses) confirmed our results. Overall, our findings suggested that pluripotent stem cell derivatives may still bear oncogenic properties even after differentiation, and additional stringent functional assays to purify these cells should be done before they can be used for regenerative therapy.

  10. Derivation of the human embryonic stem cell line RCM1

    Directory of Open Access Journals (Sweden)

    P.A. De Sousa

    2016-03-01

    Full Text Available The human embryonic stem cell line RCM-1 was derived from a failed to fertilise egg undergoing parthenogenetic stimulation. The cell line shows normal pluripotency marker expression and differentiation to three germ layers in vitro and in vivo. It has a normal 46XX female karyotype and microsatellite PCR identity, HLA and blood group typing data is available.

  11. Mapping the calcitonin receptor in human brain stem

    DEFF Research Database (Denmark)

    Bower, Rebekah L; Eftekhari, Sajedeh; Waldvogel, Henry J

    2016-01-01

    understanding of these hormone systems by mapping CTR expression in the human brain stem, specifically the medulla oblongata. Widespread CTR-like immunoreactivity was observed throughout the medulla. Dense CTR staining was noted in several discrete nuclei, including the nucleus of the solitary tract...

  12. Raman microscopy of individual living human embryonic stem cells

    DEFF Research Database (Denmark)

    Novikov, Sergey M.; Beermann, Jonas; Bozhevolnyi, Sergey I.

    2010-01-01

    We demonstrate the possibility of mapping the distribution of different biomolecules in living human embryonic stem cells grown on glass substrates, without the need for fluorescent markers. In our work we improve the quality of measurements by finding a buffer that gives low fluorescence, growing...

  13. Differentiation of neuroepithelia from human embryonic stem cells

    OpenAIRE

    2009-01-01

    We describe the method for in vitro differentiation of neuroepithelial cells from human embryonic stem cells under a chemically defined condition. The protocol is established following the fundamental principle of in vivo neuroectodermal specification. The primitive neuroepithelial cells generated by this protocol can be further induced into neuronal and glia cells with forebrain, mid/hind brain, and spinal cord identities.

  14. Improved genetic manipulation of human embryonic stem cells.

    NARCIS (Netherlands)

    Braam, S.R.; Denning, C.; van den Brink, S.; Kats, P.; Hochstenbach, R.; Passier, R.; Mummery, C.L.

    2008-01-01

    Low efficiency of transfection limits the ability to genetically manipulate human embryonic stem cells (hESCs), and differences in cell derivation and culture methods require optimization of transfection protocols. We transiently transferred multiple independent hESC lines with different growth requ

  15. Expansion of human cord blood hematopoietic stem cells for transplantation.

    Science.gov (United States)

    Chou, Song; Chu, Pat; Hwang, William; Lodish, Harvey

    2010-10-08

    A recent Science paper reported a purine derivative that expands human cord blood hematopoietic stem cells in culture (Boitano et al., 2010) by antagonizing the aryl hydrocarbon receptor. Major problems need to be overcome before ex vivo HSC expansion can be used clinically.

  16. Arrangement of collagen fibers in human placental stem villi

    NARCIS (Netherlands)

    Sati, Leyla; Demir, Ayse Yasemin; Sarikcioglu, Levent; Demir, Ramazan

    2008-01-01

    The aim of the study was to investigate the arrangements and related localization patterns of different collagen types in the stroma of placental stem villi by immunohistochemistry and electron microscopy. A total of 14 normal human term placental tissue samples were studied. Immunohistochemistry wa

  17. Arrangement of collagen fibers in human placental stem villi

    NARCIS (Netherlands)

    Sati, Leyla; Demir, Ayse Yasemin; Sarikcioglu, Levent; Demir, Ramazan

    2008-01-01

    The aim of the study was to investigate the arrangements and related localization patterns of different collagen types in the stroma of placental stem villi by immunohistochemistry and electron microscopy. A total of 14 normal human term placental tissue samples were studied. Immunohistochemistry

  18. MicroRNA Regulation of Human Breast Cancer Stem Cells

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    Yohei Shimono

    2015-12-01

    Full Text Available MicroRNAs (miRNAs are involved in virtually all biological processes, including stem cell maintenance, differentiation, and development. The dysregulation of miRNAs is associated with many human diseases including cancer. We have identified a set of miRNAs differentially expressed between human breast cancer stem cells (CSCs and non-tumorigenic cancer cells. In addition, these miRNAs are similarly upregulated or downregulated in normal mammary stem/progenitor cells. In this review, we mainly describe the miRNAs that are dysregulated in human breast CSCs directly isolated from clinical specimens. The miRNAs and their clusters, such as the miR-200 clusters, miR-183 cluster, miR-221-222 cluster, let-7, miR-142 and miR-214, target the genes and pathways important for stem cell maintenance, such as the self-renewal gene BMI1, apoptosis, Wnt signaling, Notch signaling, and epithelial-to-mesenchymal transition. In addition, the current evidence shows that metastatic breast CSCs acquire a phenotype that is different from the CSCs in a primary site. Thus, clarifying the miRNA regulation of the metastatic breast CSCs will further advance our understanding of the roles of human breast CSCs in tumor progression.

  19. Establishment of human embryonic stem cell line from gamete donors

    Institute of Scientific and Technical Information of China (English)

    LI Tao; ZHOU Can-quan; MAI Qing-yun; ZHUANG Guang-lun

    2005-01-01

    Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study. Methods Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed.Results Four ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line (cHES-1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types.Conclusions HES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widespread impact on biomedical research.

  20. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  1. Differentiation of human embryonic stem cells and induced pluripotent stem cells to cardiomyocytes: a methods overview.

    Science.gov (United States)

    Mummery, Christine L; Zhang, Jianhua; Ng, Elizabeth S; Elliott, David A; Elefanty, Andrew G; Kamp, Timothy J

    2012-07-20

    Since human embryonic stem cells were first differentiated to beating cardiomyocytes a decade ago, interest in their potential applications has increased exponentially. This has been further enhanced over recent years by the discovery of methods to induce pluripotency in somatic cells, including those derived from patients with hereditary cardiac diseases. Human pluripotent stem cells have been among the most challenging cell types to grow stably in culture, but advances in reagent development now mean that most laboratories can expand both embryonic and induced pluripotent stem cells robustly using commercially available products. However, differentiation protocols have lagged behind and in many cases only produce the cell types required with low efficiency. Cardiomyocyte differentiation techniques were also initially inefficient and not readily transferable across cell lines, but there are now a number of more robust protocols available. Here, we review the basic biology underlying the differentiation of pluripotent cells to cardiac lineages and describe current state-of-the-art protocols, as well as ongoing refinements. This should provide a useful entry for laboratories new to this area to start their research. Ultimately, efficient and reliable differentiation methodologies are essential to generate desired cardiac lineages to realize the full promise of human pluripotent stem cells for biomedical research, drug development, and clinical applications.

  2. Nanotopography Promotes Pancreatic Differentiation of Human Embryonic Stem Cells and Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Kim, Jong Hyun; Kim, Hyung Woo; Cha, Kyoung Je; Han, Jiyou; Jang, Yu Jin; Kim, Dong Sung; Kim, Jong-Hoon

    2016-03-22

    Although previous studies suggest that nanotopographical features influence properties and behaviors of stem cells, only a few studies have attempted to derive clinically useful somatic cells from human pluripotent stem cells using nanopatterned surfaces. In the present study, we report that polystyrene nanopore-patterned surfaces significantly promote the pancreatic differentiation of human embryonic and induced pluripotent stem cells. We compared different diameters of nanopores and showed that 200 nm nanopore-patterned surfaces highly upregulated the expression of PDX1, a critical transcription factor for pancreatic development, leading to an approximately 3-fold increase in the percentage of differentiating PDX1(+) pancreatic progenitors compared with control flat surfaces. Furthermore, in the presence of biochemical factors, 200 nm nanopore-patterned surfaces profoundly enhanced the derivation of pancreatic endocrine cells producing insulin, glucagon, or somatostatin. We also demonstrate that nanopore-patterned surface-induced upregulation of PDX1 is associated with downregulation of TAZ, suggesting the potential role of TAZ in nanopore-patterned surface-mediated mechanotransduction. Our study suggests that appropriate cytokine treatments combined with nanotopographical stimulation could be a powerful tool for deriving a high purity of desired cells from human pluripotent stem cells.

  3. Connexin mutant embryonic stem cells and human diseases

    Institute of Scientific and Technical Information of China (English)

    Kiyomasa; Nishii; Yosaburo; Shibata; Yasushi; Kobayashi

    2014-01-01

    Intercellular communication via gap junctions allows cells within multicellular organisms to share small molecules. The effect of such interactions has been elucidated using mouse gene knockout strategies. Although several mutations in human gap junction-encoding connexin(Cx) have been described, Cx mutants in mice do not always recapitulate the human disease. Among the 20 mouse Cxs, Cx26, Cx43, and Cx45 play roles in early cardiac or placental development, and disruption of the genes results in lethality that hampers further analyses. Embryonic stem cells(ESCs) that lack Cx43 or Cx45 have made analysis feasible in both in vitro differentiated cell cultures and in vivo chimeric tissues. The success of mouse ESCs studies is leading to the use of induced pluripotent stem cells to learn more about the pathogenesis of human Cx diseases. This review summarizes the current status of mouse Cx disruption models and ESC differentiation studies, and discusses their implication for understanding human Cx diseases.

  4. Connexin mutant embryonic stem cells and human diseases.

    Science.gov (United States)

    Nishii, Kiyomasa; Shibata, Yosaburo; Kobayashi, Yasushi

    2014-11-26

    Intercellular communication via gap junctions allows cells within multicellular organisms to share small molecules. The effect of such interactions has been elucidated using mouse gene knockout strategies. Although several mutations in human gap junction-encoding connexin (Cx) have been described, Cx mutants in mice do not always recapitulate the human disease. Among the 20 mouse Cxs, Cx26, Cx43, and Cx45 play roles in early cardiac or placental development, and disruption of the genes results in lethality that hampers further analyses. Embryonic stem cells (ESCs) that lack Cx43 or Cx45 have made analysis feasible in both in vitro differentiated cell cultures and in vivo chimeric tissues. The success of mouse ESCs studies is leading to the use of induced pluripotent stem cells to learn more about the pathogenesis of human Cx diseases. This review summarizes the current status of mouse Cx disruption models and ESC differentiation studies, and discusses their implication for understanding human Cx diseases.

  5. Noninvasive Metabolomic Profiling of Human Embryo Culture Media Using a Simple Spectroscopy Adjunct to Morphology for Embryo Assessment in in Vitro Fertilization (IVF

    Directory of Open Access Journals (Sweden)

    Jiming Hu

    2013-03-01

    Full Text Available Embryo quality is crucial to the outcome of in vitro fertilization (IVF; however, the ability to precisely distinguish the embryos with higher reproductive potential from others is poor. Morphologic evaluation used to play an important role in assessing embryo quality, but it is somewhat subjective. The culture medium is the immediate environment of the embryos in vitro, and a change of the substances in the culture medium is possibly related to the embryo quality. Thus, the present study aims to determine whether metabolomic profiling of the culture medium using Raman spectroscopy adjunct to morphology correlates with the reproductive potential of embryos in IVF and, thus, to look for a new method of assessing embryo quality. Fifty seven spent media samples were detected by Raman spectroscopy. Combined with embryo morphology scores, we found that embryos in culture media with less than 0.012 of sodium pyruvate and more than −0.00085 phenylalanine have a high reproductive potential, with up to 85.7% accuracy compared with clinical pregnancy. So, sodium pyruvate and phenylalanine in culture medium play an important role in the development of the embryo. Raman spectroscopy is an important tool that provides a new and accurate assessment of higher quality embryos.

  6. Xeno-free culture of human periodontal ligament stem cells.

    Science.gov (United States)

    Trubiani, Oriana; Diomede, Francesca

    2015-01-01

    The possibility of transplanting adult stem cells into damaged organs has opened a new prospective for the treatment of several human pathologies. Currently, in vitro expansion and culture of mesenchymal stem cells is founded on supplementing cell culture and differentiation medium with fetal calf serum (FCS) or fetal bovine serum (FBS) that contain numerous growth factors inducing cell attachment to plastic surfaces, proliferation, and differentiation. Mesenchymal stem cells (MSCs) cultured with medium containing FCS or FBS are unusable in the cell therapy; in fact the central issues regarding limitations in using animal sera for cell therapy is that its components are highly variable and often unknown and may trigger a xenogenic immune response, immunological reactions, and the potential transmission of prion diseases and zoonoses. Here we describe the culture system protocols for the expansion and production of human Periodontal Ligament Stem Cells (hPDLSCs) using a new xeno-free medium formulation ensuring the maintenance of the stem cells features comprising the multiple passage expansion, mesengenic lineage differentiation, cellular phenotype, and genomic stability, essential elements for conforming to translation to cell therapy.

  7. Stem cell factor and c-Kit in human primordial germ cells and fetal ovaries

    DEFF Research Database (Denmark)

    Høyer, Poul Erik; Byskov, Anne Grete; Møllgård, Kjeld

    2005-01-01

    Prenatal ovary (human), Primordial germ cells, Folliculogenesis, c-Kit, Stem cell factor, immunohistochemistry......Prenatal ovary (human), Primordial germ cells, Folliculogenesis, c-Kit, Stem cell factor, immunohistochemistry...

  8. Neural Stem Cells Derived from Human Parthenogenetic Stem Cells Engraft and Promote Recovery in a Nonhuman Primate Model of Parkinson's Disease.

    Science.gov (United States)

    Gonzalez, Rodolfo; Garitaonandia, Ibon; Poustovoitov, Maxim; Abramihina, Tatiana; McEntire, Caleb; Culp, Ben; Attwood, Jordan; Noskov, Alexander; Christiansen-Weber, Trudy; Khater, Marwa; Mora-Castilla, Sergio; To, Cuong; Crain, Andrew; Sherman, Glenn; Semechkin, Andrey; Laurent, Louise C; Elsworth, John D; Sladek, John; Snyder, Evan Y; Redmond, D Eugene; Kern, Russell A

    2016-11-01

    Cell therapy has attracted considerable interest as a promising therapeutic alternative for patients with Parkinson's disease (PD). Clinical studies have shown that grafted fetal neural tissue can achieve considerable biochemical and clinical improvements in PD. However, the source of fetal tissue grafts is limited and ethically controversial. Human parthenogenetic stem cells offer a good alternative because they are derived from unfertilized oocytes without destroying potentially viable human embryos and can be used to generate an unlimited supply of neural cells for transplantation. We have previously reported that human parthenogenetic stem cell-derived neural stem cells (hpNSCs) successfully engraft, survive long term, and increase brain dopamine (DA) levels in rodent and nonhuman primate models of PD. Here we report the results of a 12-month transplantation study of hpNSCs in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned African green monkeys with moderate to severe clinical parkinsonian symptoms. The hpNSCs manufactured under current good manufacturing practice (cGMP) conditions were injected bilaterally into the striatum and substantia nigra of immunosuppressed monkeys. Transplantation of hpNSCs was safe and well tolerated by the animals with no dyskinesia, tumors, ectopic tissue formation, or other test article-related serious adverse events. We observed that hpNSCs promoted behavioral recovery; increased striatal DA concentration, fiber innervation, and number of dopaminergic neurons; and induced the expression of genes and pathways downregulated in PD compared to vehicle control animals. These results provide further evidence for the clinical translation of hpNSCs and support the approval of the world's first pluripotent stem cell-based phase I/IIa study for the treatment of PD (Clinical Trial Identifier NCT02452723).

  9. The Isolation and Characterization of Human Prostate Cancer Stem Cells

    Science.gov (United States)

    2015-05-01

    IGF1, SOX15, BMPR1B, TGFBR1, etc), which fall into distinct GO categories including SC, development, stress response, and wound healing (unpublished...prostate cancer through the elucidation of the role of cancer stem cells in the pathogenesis of the disease. During the past year, we have made the...studies, ii) in vitro co-culture of human prostate cancer cells (established cell lines and primary patient samples) with human prostate fibroblasts

  10. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin

    OpenAIRE

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34+ hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex...

  11. Human pluripotent stem cells: applications and challenges in neurological diseases

    Directory of Open Access Journals (Sweden)

    Youssef eHIBAOUI

    2012-07-01

    Full Text Available The ability to generate human pluripotent stem cells (hPSCs holds great promise for the understanding and the treatment of human neurological diseases in modern medicine. The hPSCs are considered for their in vitro use as research tools to provide relevant cellular model for human diseases, drug discovery and toxicity assays and for their in vivo use in regenerative medicine applications. In this review, we highlight recent progress, promises and challenges of hPSC applications in human neurological disease modelling and therapies.

  12. Use of human pluripotent stem cells to study and treatretinopathies

    Institute of Scientific and Technical Information of China (English)

    Karim Ben M’Barek; Florian Regent; Christelle Monville

    2015-01-01

    Human cell types affected by retinal diseases (such asage-related macular degeneration or retinitis pimentosa)are limited in cell number and of reduced accessibility. As aconsequence, their isolation for in vitro studies of diseasemechanisms or for drug screening efforts is fastidious.Human pluripotent stem cells (hPSCs), either of embryonicorigin or through reprogramming of adult somatic cells,represent a new promising way to generate models ofhuman retinopathies, explore the physiopathologicalmechanisms and develop novel therapeutic strategies.Disease-specific human embryonic stem cells were thefirst source of material to be used to study certain diseasestates. The recent demonstration that human somaticcells, such as fibroblasts or blood cells, can be geneticallyconverted to induce pluripotent stem cells together withthe continuous improvement of methods to differentiatethese cells into disease-affected cellular subtypes opensnew perspectives to model and understand a largenumber of human pathologies, including retinopathies.This review focuses on the added value of hPSCs for thedisease modeling of human retinopathies and the study oftheir molecular pathological mechanisms. We also discussthe recent use of these cells for establishing the validationstudies for therapeutic intervention and for the screeningof large compound libraries to identify candidate drugs.

  13. Human BMP sequences can confer normal dorsal-ventral patterning in the Drosophila embryo.

    Science.gov (United States)

    Padgett, R W; Wozney, J M; Gelbart, W M

    1993-04-01

    The type beta transforming growth factor family is composed of a series of processed, secreted growth factors, several of which have been implicated in important regulatory roles in cell determination, inductive interactions, and tissue differentiation. Among these factors, the sequence of the DPP protein from Drosophila is most similar to two of the vertebrate bone morphogenetic proteins, BMP2 and BMP4. Here we report that the human BMP4 ligand sequences can function in lieu of DPP in Drosophila embryos. We introduced the ligand region from human BMP4 into a genomic fragment of the dpp gene in place of the Drosophila ligand sequences and recovered transgenic flies by P-element transformation. We find that this chimeric dpp-BMP4 transgene can completely rescue the embryonic dorsal-ventral patterning defect of null dpp mutant genotypes. We infer that the chimeric DPP-BMP4 protein can be processed properly and, by analogy with the action of other family members, can activate the endogenous DPP receptor to carry out the events necessary for dorsal-ventral patterning. Our evidence suggests that the DPP-BMP4 signal transduction pathway has been functionally conserved for at least 600 million years.

  14. Human Embryonic Stem Cell Research: Ethical Views of Buddhist, Hindu and Catholic Leaders in Malaysia.

    Science.gov (United States)

    Sivaraman, Mathana Amaris Fiona; Noor, Siti Nurani Mohd

    2016-04-01

    Embryonic Stem Cell Research (ESCR) raises ethical issues. In the process of research, embryos may be destroyed and, to some, such an act entails the 'killing of human life'. Past studies have sought the views of scientists and the general public on the ethics of ESCR. This study, however, explores multi-faith ethical viewpoints, in particular, those of Buddhists, Hindus and Catholics in Malaysia, on ESCR. Responses were gathered via semi-structured, face-to-face interviews. Three main ethical quandaries emerged from the data: (1) sanctity of life, (2) do no harm, and (3) 'intention' of the research. Concerns regarding the sanctity of life are directed at particular research protocols which interfere with religious notions of human ensoulment and early consciousness. The principle of 'do no harm' which is closely related to ahimsa prohibits all acts of violence. Responses obtained indicate that respondents either discourage research that inflicts harm on living entities or allow ESCR with reservations. 'Intention' of the research seems to be an interesting and viable rationale that would permit ESCR for the Buddhists and Hindus. Research that is intended for the purpose of alleviating human suffering is seen as being ethical. This study also notes that Catholics oppose ESCR on the basis of the inviolability of human life.

  15. Stable genetic modification of human embryonic stem cells by lentiviral vectors.

    Science.gov (United States)

    Gropp, Michal; Itsykson, Pavel; Singer, Orna; Ben-Hur, Tamir; Reinhartz, Etti; Galun, Eithan; Reubinoff, Benjamin E

    2003-02-01

    Human embryonic stem (hES) cells are pluripotent cells derived from the inner cell mass of the early preimplantation embryo. An efficient strategy for stable genetic modification of hES cells may be highly valuable for manipulating the cells in vitro and may promote the study of hES cell biology, human embryogenesis, and the development of cell-based therapies. Here, we demonstrate that vectors derived from self-inactivating (SIN) human immunodeficiency virus type 1 (HIV-1) are efficient tools for stable genetic modification of hES cells. Transduction of hES cells by a modified vector derived from SIN HIV-1 and containing the woodchuck hepatitis regulatory element (WPRE) and the central polypurine tract (cPPT) sequence facilitated stable transgene expression during prolonged (38 weeks) undifferentiated proliferation in vitro. Southern blot analysis revealed that the viral vector had integrated into the host cells' DNA. Transgene expression was maintained throughout differentiation into progeny of all three germ layers both in vitro and in vivo in teratomas. Thus, the transduced hES cells retained the capability for self-renewal and their pluripotent potential. Genetic modification of hES cells by lentiviral vectors provides a powerful tool for basic and applied research in the area of human ES cells.

  16. Activation of endogenous human stem cell-associated retroviruses (SCARs) and therapy-resistant phenotypes of malignant tumors.

    Science.gov (United States)

    Glinsky, Gennadi V

    2016-07-01

    Recent reports revealed consistent activation of specific endogenous retroviral elements in human preimplantation embryos and embryonic stem cells. Activity of stem cell associated retroviruses (SCARs) has been implicated in seeding thousands of human-specific regulatory sequences in the hESC genome. Activation of specific SCARs has been demonstrated in patients diagnosed with multiple types of cancer, autoimmune diseases, and neurodegenerative disorders, and appears associated with clinically lethal therapy resistant death-from-cancer phenotypes in a sub-set of cancer patients diagnosed with different types of malignant tumors. A hallmark feature of human-specific SCAR integration sites is deletions of ancestral DNA. Analysis of human-specific genetic loci of SCARs' stemness networks in tumor samples of TCGA cohorts representing 29 cancer types suggests that this approach may facilitate identification of pan-cancer genomic signatures of clinically-lethal disease defined by the presence of somatic non-silent mutations, gene-level copy number changes, and transcripts and proteins' expression of SCAR-regulated host genes. Present analyses indicate that multiple lines of strong circumstantial evidence support the hypothesis that activation of SCARs' networks may play an important role in cancer progression and metastasis, perhaps contributing to the emergence of clinically-lethal therapy-resistant death-from-cancer phenotypes.

  17. Nanoscale Mechanical Stimulation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    H Nikukar

    2014-05-01

    We observed significant responses after 1 and 2-week stimulations in cell number, cell shapes and phenotypical markers. Microarray was performed for all groups. Cell count showed normal cell growth with stimulation. However, cell surface area, cell perimeter, and arboration after 1-week stimulation showed significant increases. Immunofluorescent studies have showed significant increase in osteocalcin production after stimulation. Conclusions: Nanoscale mechanical vibration showed significant changes in human mesenchymal stem cell behaviours. Cell morphology changed to become more polygonal and increased expression of the osteoblast markers were noted. These findings with gene regulation changes suggesting nanoscale mechanostimulation has stimulated osteoblastogenesis.  Keywords:  Mesenchymal, Nanoscale, Stem Cells.

  18. Effect of intrauterine injection of human chorionic gonadotropin before embryo transfer on pregnancy rate: A prospective randomized study.

    Science.gov (United States)

    Mostajeran, Fatemeh; Godazandeh, Farzaneh; Ahmadi, Sayed Mehdi; Movahedi, Minoo; Jabalamelian, Seyed Abolfazl

    2017-01-01

    Human chorionic gonadotropin (hCG) as the most important factor to controlled implantation is one of the early embryonic signals in primates that is secreted by the embryo before its implantation. This study was designed to assess the effects of intrauterine injection of hCG before the embryo transfer in an in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycle on pregnancy rate in infertile patients. This randomized study was done on 100 infertile patients in two groups: intervention group received injection of 700 IU of intrauterine hCG 10 min before embryo transfer and control group did not receive hCG. The pregnancy rate was tested 2 weeks after embryo transfer, and if the pregnancy test was positive, a transvaginal ultrasound was performed 3 weeks later to search for signs of pregnancy, such as the presence of a gestational sac, embryo, and fetal heart rate, and confirmed as successful pregnancy. Pregnancy test was positive in 13 (28.6%) of 46 patients in hCG group and in control group was positive in 6 (12.5%) of 48 patients. The pregnancy rate between hCG group and control group was not significantly different (P = 0.54). The pregnancy rate in hCG group with IVF fertilization was 20.8% and in their controls was 7.4% (P = 0.51). The pregnancy rate in hCG group with ICSI fertilization was 36.4% and in their controls was 19% (P = 0.16). The intrauterine injection of 700 IU of hCG before embryo transfer improved pregnancy rate compared to control group but was not significantly different.

  19. Immunomodulatory properties of human adult and fetal multipotent mesenchymal stem cells.

    Science.gov (United States)

    Chen, Pei-Min; Yen, Men-Luh; Liu, Ko-Jiunn; Sytwu, Huey-Kang; Yen, B-Linju

    2011-07-18

    In recent years, a large number of studies have contributed to our understanding of the immunomodulatory mechanisms used by multipotent mesenchymal stem cells (MSCs). Initially isolated from the bone marrow (BM), MSCs have been found in many tissues but the strong immunomodulatory properties are best studied in BM MSCs. The immunomodulatory effects of BM MSCs are wide, extending to T lymphocytes and dendritic cells, and are therapeutically useful for treatment of immune-related diseases including graft-versus-host disease as well as possibly autoimmune diseases. However, BM MSCs are very rare cells and require an invasive procedure for procurement. Recently, MSCs have also been found in fetal-stage embryo-proper and extra-embryonic tissues, and these human fetal MSCs (F-MSCs) have a higher proliferative profile, and are capable of multilineage differentiation as well as exert strong immunomodulatory effects. As such, these F-MSCs can be viewed as alternative sources of MSCs. We review here the current understanding of the mechanisms behind the immunomodulatory properties of BM MSCs and F-MSCs. An increase in our understanding of MSC suppressor mechanisms will offer insights for prevalent clinical use of these versatile adult stem cells in the near future.

  20. Hydrogen peroxide induces adaptive response and differential gene expression in human embryo lung fibroblast cells.

    Science.gov (United States)

    Wei, Qinzhi; Huang, Haiyan; Yang, Linqing; Yuan, Jianhui; Yang, Xiaohua; Liu, Yungang; Zhuang, Zhixiong

    2014-04-01

    Hydrogen peroxide (H2 O2 ), a substance involved in cellular oxidative stress, has been observed to induce an adaptive response, which is characterized by a protection against the toxic effect of H2 O2 at higher concentrations. However, the molecular mechanism for the adaptive response remains unclear. In particular, the existing reports on H2 O2 -induced adaptive response are limited to animal cells and human tumor cells, and relatively normal human cells have never been observed for an adaptive response to H2 O2 . In this study, a human embryo lung fibroblast (MRC-5) cell line was used to model an adaptive response to H2 O2 , and the relevant differential gene expressions by using fluoro mRNA differential display RT-PCR. The results showed significant suppression of cytotoxicity of H2 O2 (1100 μM, 1 h) after pretreatment of the cells with H2 O2 at lower concentrations (0.088-8.8 μM, 24 h), as indicated by cell survival, lactate dehydrogenase release, and the rate of apoptotic cells. Totally 60 mRNA components were differentially expressed compared to untreated cells, and five of them (sizing 400-600 bp) which demonstrated the greatest increase in expression were cloned and sequenced. They showed identity with known genes, such as BCL-2, eIF3S5, NDUFS4, and RPS10. Real time RT-PCR analysis of the five genes displayed a pattern of differential expression consistent with that by the last method. These five genes may be involved in the induction of adaptive response by H2 O2 in human cells, at least in this particular cell type. Copyright © 2012 Wiley Periodicals, Inc.

  1. Generation of Neurospheres from Human Adipose-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Erfang Yang

    2015-01-01

    Full Text Available Transplantation of neural stem cells (NSCs to treat neurodegenerative disease shows promise; however, the clinical application of NSCs is limited by the invasive procurement and ethical concerns. Adipose-derived stem cells (ADSCs are a source of multipotent stem cells that can self-renew and differentiate into various kinds of cells; this study intends to generate neurospheres from human ADSCs by culturing ADSCs on uncoated culture flasks in serum-free neurobasal medium supplemented with B27, basic fibroblast growth factor (bFGF, and epidermal growth factor (EGF; the ADSCs-derived neurospheres were terminally differentiated after growth factor withdrawal. Expression of Nestin, NeuN, MAP2, and GFAP in ADSCs and terminally differentiated neurospheres was shown by quantitative reverse transcription-polymerase chain reaction (qRT-PCR, western blotting, and immunocytochemistry; cell proliferation in neurospheres was evaluated by cell cycle analyses, immunostaining, and flow cytometry. These data strongly support the conclusion that human ADSCs can successfully differentiate into neurospheres efficiently on uncoated culture flasks, which present similar molecular marker pattern and proliferative ability with NSCs derived from embryonic and adult brain tissues. Therefore, human ADSCs may be an ideal alternative source of stem cells for the treatment of neurodegenerative diseases.

  2. Human embryonic stem cells carrying an unbalanced translocation demonstrate impaired differentiation into trophoblasts: an in vitro model of human implantation failure.

    Science.gov (United States)

    Shpiz, A; Kalma, Y; Frumkin, T; Telias, M; Carmon, A; Amit, A; Ben-Yosef, D

    2015-03-01

    Carriers of the balanced translocation t(11;22), the most common reciprocal translocation in humans, are at high risk of creating gametes with unbalanced translocation, leading to repeated miscarriages. Current research models for studying translocated embryos and the biological basis for their implantation failure are limited. The aim of this study was to elucidate whether human embryonic stem cells (hESCs) carrying the unbalanced chromosomal translocation t(11;22) can provide an explanation for repeated miscarriages of unbalanced translocated embryos. Fluorescent in situ hybridization and karyotype analysis were performed to analyze the t(11;22) in embryos during PGD and in the derived hESC line. The hESC line was characterized by RT-PCR and FACS analysis for pluripotent markers. Directed differentiation to trophoblasts was carried out by bone morphogenetic protein 4 (BMP4). Trophoblast development was analyzed by measuring β-hCG secretion, by β-hCG immunostaining and by gene expression of trophoblastic markers. We derived the first hESC line carrying unbalanced t(11;22), which showed the typical morphological and molecular characteristics of a hESC line. Control hESCs differentiated into trophoblasts secreted increasing levels of β-hCG and concomitantly expressed the trophoblast genes, CDX2, TP63, KRT7, ERVW1, CGA, GCM1, KLF4 and PPARG. In contrast, differentiated translocated hESCs displayed reduced and delayed secretion of β-hCG concomitant with impaired expression of the trophoblastic genes. The reduced activation of trophoblastic genes may be responsible for the impaired trophoblastic differentiation in t(11;22)-hESCs, associated with implantation failure in unbalanced t(11;22) embryos. Our t(11;22) hESCs are presented as a valuable human model for studying the mechanisms underlying implantation failure.

  3. Putative Porcine Embryonic Stem Cell Lines Derived from Aggregated Four-Celled Cloned Embryos Produced by Oocyte Bisection Cloning

    Science.gov (United States)

    Siriboon, Chawalit; Lin, Yu-Hsuan; Kere, Michel; Chen, Chun-Da; Chen, Lih-Ren; Chen, Chien-Hong; Tu, Ching-Fu; Lo, Neng-Wen; Ju, Jyh-Cherng

    2015-01-01

    We attempted to isolate ES cell lines using inner cell masses from high-quality cloned porcine blastocysts. After being seeded onto feeders, embryos had better (P cells were examined. More (17.1%) ntES cell lines over Passage 3 were generated in the MEF/KSR group. However, ntES cells cultured in KSR-supplemented medium had a low proliferation rate with defective morphology, and eventually underwent differentiation or apoptosis subsequently. Approximately 26.1, 22.7 and 35.7% of primary colonies were formed after plating embryos in DMEM, DMEM/F12 and α-MEM media, respectively. Survival rates of ntES cells cultured in α-MEM, DMEM and DMEM/F12 were 16.7, 4.3 and 6.8%, respectively (P > 0.05). We further examined the beneficial effect of TSA treatment of 3× aggregated cloned embryos on establishment of ntES cell lines. Primary colony numbers and survival rates of ntES cells beyond passage 3 were higher (P cells, remaining undifferentiated over 25 passages, had alkaline phosphatase activity and expressed ES specific markers Oct4, Nanog, Sox2, and Rex01. Moreover, these ntES cells successfully differentiated into embryoid bodies (EBs) that expressed specific genes of all three germ layers after being cultured in LIF-free medium. In conclusion, we have successfully derived putative porcine ntES cells with high efficiency from quality cloned embryos produced by embryo aggregation, and optimized the ES cell culture system suitable for establishing and maintaining ntES cell lines in undifferentiated state. PMID:25680105

  4. Cancer stem cells in human gastrointestinal cancer.

    Science.gov (United States)

    Taniguchi, Hiroaki; Moriya, Chiharu; Igarashi, Hisayoshi; Saitoh, Anri; Yamamoto, Hiroyuki; Adachi, Yasushi; Imai, Kohzoh

    2016-11-01

    Cancer stem cells (CSCs) are thought to be responsible for tumor initiation, drug and radiation resistance, invasive growth, metastasis, and tumor relapse, which are the main causes of cancer-related deaths. Gastrointestinal cancers are the most common malignancies and still the most frequent cause of cancer-related mortality worldwide. Because gastrointestinal CSCs are also thought to be resistant to conventional therapies, an effective and novel cancer treatment is imperative. The first reported CSCs in a gastrointestinal tumor were found in colorectal cancer in 2007. Subsequently, CSCs were reported in other gastrointestinal cancers, such as esophagus, stomach, liver, and pancreas. Specific phenotypes could be used to distinguish CSCs from non-CSCs. For example, gastrointestinal CSCs express unique surface markers, exist in a side-population fraction, show high aldehyde dehydrogenase-1 activity, form tumorspheres when cultured in non-adherent conditions, and demonstrate high tumorigenic potential in immunocompromised mice. The signal transduction pathways in gastrointestinal CSCs are similar to those involved in normal embryonic development. Moreover, CSCs are modified by the aberrant expression of several microRNAs. Thus, it is very difficult to target gastrointestinal CSCs. This review focuses on the current research on gastrointestinal CSCs and future strategies to abolish the gastrointestinal CSC phenotype.

  5. Knockdown of E2F2 inhibits tumorigenicity, but preserves stemness of human embryonic stem cells.

    Science.gov (United States)

    Suzuki, Daniela Emi; Nakahata, Adriana Miti; Okamoto, Oswaldo Keith

    2014-06-01

    Tumorigenicity of human pluripotent stem cells is a major threat limiting their application in cell therapy protocols. It remains unclear, however, whether suppression of tumorigenic potential can be achieved without critically affecting pluripotency. A previous study has identified hyperexpressed genes in cancer stem cells, among which is E2F2, a gene involved in malignant transformation and stem cell self-renewal. Here we tested whether E2F2 knockdown would affect the proliferative capacity and tumorigenicity of human embryonic stem cells (hESC). Transient E2F2 silencing in hESC significantly inhibited expression of the proto-oncogenes BMI1 and HMGA1, in addition to proliferation of hESC, indicated by a higher proportion of cells in G1, fewer cells in G2/M phase, and a reduced capacity to generate hESC colonies in vitro. Nonetheless, E2F2-silenced cells kept expression of typical pluripotency markers and displayed differentiation capacity in vitro. More importantly, E2F2 knockdown in hESC significantly inhibited tumor growth in vivo, which was considerably smaller than tumors generated from control hESC, although displaying typical teratoma traits, a major indicator of pluripotency retention in E2F2-silenced cells. These results suggest that E2F2 knockdown can inhibit hESC proliferation and tumorigenicity without significantly harming stemness, providing a rationale to future protocols aiming at minimizing risks related to therapeutic application of cells and/or products derived from human pluripotent cells.

  6. Techniques of Human Embryonic Stem Cell and Induced Pluripotent Stem Cell Derivation.

    Science.gov (United States)

    Lewandowski, Jarosław; Kurpisz, Maciej

    2016-10-01

    Developing procedures for the derivation of human pluripotent stem cells (PSCs) gave rise to novel pathways into regenerative medicine research. For many years, stem cells have attracted attention as a potentially unlimited cell source for cellular therapy in neurodegenerative disorders, cardiovascular diseases, and spinal cord injuries, for example. In these studies, adult stem cells were insufficient; therefore, many attempts were made to obtain PSCs by other means. This review discusses key issues concerning the techniques of pluripotent cell acquisition. Technical and ethical issues hindered the medical use of somatic cell nuclear transfer and embryonic stem cells. Therefore, induced PSCs (iPSCs) emerged as a powerful technique with great potential for clinical applications, patient-specific disease modelling and pharmaceutical studies. The replacement of viral vectors or the administration of analogous proteins or chemical compounds during cell reprogramming are modifications designed to reduce tumorigenesis risk and to augment the procedure efficiency. Intensified analysis of new PSC lines revealed other barriers to overcome, such as epigenetic memory, disparity between human and mouse pluripotency, and variable response to differentiation of some iPSC lines. Thus, multidimensional verification must be conducted to fulfil strict clinical-grade requirements. Nevertheless, the first clinical trials in patients with spinal cord injury and macular dystrophy were recently carried out with differentiated iPSCs, encouraging alternative strategies for potential autologous cellular therapies.

  7. Generating trunk neural crest from human pluripotent stem cells.

    Science.gov (United States)

    Huang, Miller; Miller, Matthew L; McHenry, Lauren K; Zheng, Tina; Zhen, Qiqi; Ilkhanizadeh, Shirin; Conklin, Bruce R; Bronner, Marianne E; Weiss, William A

    2016-01-27

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior "cranial" NCC form craniofacial bone, whereas solely posterior "trunk" NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typically occur before pregnancy is detectable. As a result, current knowledge of NCC biology derives primarily from non-human organisms. Important differences between human and non-human NCC, such as expression of HNK1 in human but not mouse NCC, suggest a need to study human NCC directly. Here, we demonstrate that current protocols to differentiate human pluripotent stem cells (PSC) to NCC are biased toward cranial NCC. Addition of retinoic acid drove trunk-related markers and HOX genes characteristic of a posterior identity. Subsequent treatment with bone morphogenetic proteins (BMPs) enhanced differentiation to sympathoadrenal cells. Our approach provides methodology for detailed studies of human NCC, and clarifies roles for retinoids and BMPs in the differentiation of human PSC to trunk NCC and to sympathoadrenal lineages.

  8. Low microRNA-199a expression in human amniotic epithelial cell feeder layers maintains human-induced pluripotent stem cell pluripotency via increased leukemia inhibitory factor expression

    Institute of Scientific and Technical Information of China (English)

    Te Liu; Qing Chen; Yongyi Huang; Qin Huang; Lizhen Jiang; Lihe Guo

    2012-01-01

    Human-induced pluripotent stem (iPS) cells share the same key properties as embryonic stem cells,and may be generated from patient- or disease-specific sources,which makes them attractive for personalized medicine,drug screens,or cellular therapy.Long-term cultivation and maintenance of normal iPS cells in an undifferentiated self-renewing state is a major challenge.Our previous studies have shown that human amniotic epithelial cells (HuAECs) could provide a good source of feeder cells for mouse and human embryonic stem cells,or spermatogonial stem cells,as they express endogenous leukemia inhibitory factor (LIF) at high levels.Here,we examined the effect of exogenous microRNA-199a regulation on endogenous LIF expression in HuAECs,and in torn on human iPS cell pluripotency.We found that HuAECs feeder cells transfected with microRNA-199a mutant expressed LIF at high levels,allowing iPS to maintain a high level of alkaline phosphatase activity in longterm culture and form teratomas in severe combined immunodeficient mice.The expression of stem cell markers was increased in iPS cultured on HuAECs feeder cells transfected with the microRNA-199a mutant,compared with iPS cultured on HuAECs transfected with microRNA-199a or mouse embryo fibroblasts.Taken together,these results suggested that LIF expression might be regulated by microRNA-199a,and LIF was a crucial component in feeder cells,and also was required for maintenance of human iPS cells in an undifferentiated,proliferative state capable of self-renewal.

  9. My Corporis Fabrica Embryo: An ontology-based 3D spatio-temporal modeling of human embryo development

    OpenAIRE

    Rabattu, Pierre-Yves; Massé, Benoit; Ulliana, Federico; Rousset, Marie-Christine; Rohmer, Damien; Léon, Jean-Claude; Palombi, Olivier

    2015-01-01

    Background Embryology is a complex morphologic discipline involving a set of entangled mechanisms, sometime difficult to understand and to visualize. Recent computer based techniques ranging from geometrical to physically based modeling are used to assist the visualization and the simulation of virtual humans for numerous domains such as surgical simulation and learning. On the other side, the ontology-based approach applied to knowledge representation is more and more successfully adopted in...

  10. Human induced pluripotent stem cells: A disruptive innovation.

    Science.gov (United States)

    De Vos, J; Bouckenheimer, J; Sansac, C; Lemaître, J-M; Assou, S

    2016-01-01

    This year (2016) will mark the 10th anniversary of the discovery of induced pluripotent stem cells (iPSCs). The finding that the transient expression of four transcription factors can radically remodel the epigenome, transcriptome and metabolome of differentiated cells and reprogram them into pluripotent stem cells has been a major and groundbreaking technological innovation. In this review, we discuss the major applications of this technology that we have grouped in nine categories: a model to study cell fate control; a model to study pluripotency; a model to study human development; a model to study human tissue and organ physiology; a model to study genetic diseases in a dish; a tool for cell rejuvenation; a source of cells for drug screening; a source of cells for regenerative medicine; a tool for the production of human organs in animals.

  11. Generation of induced pluripotent stem cells from human cord blood.

    Science.gov (United States)

    Haase, Alexandra; Olmer, Ruth; Schwanke, Kristin; Wunderlich, Stephanie; Merkert, Sylvia; Hess, Christian; Zweigerdt, Robert; Gruh, Ina; Meyer, Johann; Wagner, Stefan; Maier, Lars S; Han, Dong Wook; Glage, Silke; Miller, Konstantin; Fischer, Philipp; Schöler, Hans R; Martin, Ulrich

    2009-10-02

    Induced pluripotent stem cells (iPSCs) may represent an ideal cell source for future regenerative therapies. A critical issue concerning the clinical use of patient-specific iPSCs is the accumulation of mutations in somatic (stem) cells over an organism's lifetime. Acquired somatic mutations are passed onto iPSCs during reprogramming and may be associated with loss of cellular functions and cancer formation. Here we report the generation of human iPSCs from cord blood (CB) as a juvenescent cell source. CBiPSCs show characteristics typical of embryonic stem cells and can be differentiated into derivatives of all three germ layers, including functional cardiomyocytes. For future therapeutic production of autologous and allogeneic iPSC derivatives, CB could be routinely harvested for public and commercial CB banks without any donor risk. CB could readily become available for pediatric patients and, in particular, for newborns with genetic diseases or congenital malformations.

  12. Measurement of human embryonic stem cell in the growing cycle

    Science.gov (United States)

    Li, X.; Zhao, L.; Oh, Steve K. W.; Chong, W. K.; Ong, J. K.; Chen, Allen K.; Choo, Andre B. H.

    2008-09-01

    A measurement and imaging system has been developed for in-line continuous measurement of live, unmodified, human embryonic stem cells (hESC). The measurement will not affect cell growth, structure, sterility and suitability for clinical use. The stem cell imaging system (SCIS) can be used to support the optimization of automated stem cell growth for invitro study and for high-volume bio-manufacture. This paper present the experimental and analysis for the optimization of system parameters. A non-linear lighting is developed to obtain a clear images. The individual cluster can be traced from day one to day two. The whole system is calibrated with measurement microscope and haemacytometer. The measurement accuracy is better than 90%.

  13. Effect of Traditional Chinese Herbs Combined with Low Dose Human Menopausal Gonadotropin Applied in Frozen-thawed Embryo Transfer

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Objective: To assess embryo implantation rate (IR) and pregnancy rate (PR) in women who received Bushen Wengong Decoction (补肾温宫汤, BSWGD), a Chinese herbal formula, combined with low dose of human menopausal gonadotropin (hMG) prior to frozen-thawed embryo transfer (FET). Methods: A total of 262 subjects (674 transferred embryos) who received FET were analyzed retrospectively. In them,122 women were under 30 years old, 106 between 30-35 years and 32 over 35 years. The 85 subjects with normal ovulation were assigned to Group A, the natural menstruation cycling group, on whom no pre-transfer treatment was applied. The other 177 subjects with abnormal ovulation were assigned to Group B, and subdivided, according to the pre-transfer treatment they received, into three groups, Group B1 (50 cases) received BSWGD, Group B2 (58 cases) received hMG and Group B3 (69 cases) received both BSWGD and low dose hMG. The IR and PR of FET in the four groups were compared, and the effect of the embryo cryotime on PR of FET were compared also. Besides, the influencing factors to FET were analyzed. Results: IR and PR were significantly higher in all age sects of Group B3 than those in Group A, showing significant difference (P< 0.05). IR and PR in subjects in age sects of <30 years and > 35 years in group B3 were signifi cantly higher than those in Group B1 ( P<0.05), but no significant difference was shown in the two parameters between Group B 2 and Group B3 ( P>0.05). PR in the subjects who received embryos with cryo-time of > 200 days was significantly lower than that in those with cryo-time of < 100 days (P<0.05). Embryo cryo-time, endometrial thickness, use of BSWGD and use of hMG were of significance in FET ( P< 0.05).Conclusion: A programmed cycle of BSWGD combined with low dose of hMG could improve the embryo IR and PR of FET. Embryo cryo-time, endometrial thickness, and the use of BSWGD and hMG are of significance for FET.

  14. Distinct human stem cell populations in small and large intestine.

    Science.gov (United States)

    Cramer, Julie M; Thompson, Timothy; Geskin, Albert; LaFramboise, William; Lagasse, Eric

    2015-01-01

    The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease.

  15. Distinct human stem cell populations in small and large intestine.

    Directory of Open Access Journals (Sweden)

    Julie M Cramer

    Full Text Available The intestine is composed of an epithelial layer containing rapidly proliferating cells that mature into two regions, the small and the large intestine. Although previous studies have identified stem cells as the cell-of-origin for intestinal epithelial cells, no studies have directly compared stem cells derived from these anatomically distinct regions. Here, we examine intrinsic differences between primary epithelial cells isolated from human fetal small and large intestine, after in vitro expansion, using the Wnt agonist R-spondin 2. We utilized flow cytometry, fluorescence-activated cell sorting, gene expression analysis and a three-dimensional in vitro differentiation assay to characterize their stem cell properties. We identified stem cell markers that separate subpopulations of colony-forming cells in the small and large intestine and revealed important differences in differentiation, proliferation and disease pathways using gene expression analysis. Single cells from small and large intestine cultures formed organoids that reflect the distinct cellular hierarchy found in vivo and respond differently to identical exogenous cues. Our characterization identified numerous differences between small and large intestine epithelial stem cells suggesting possible connections to intestinal disease.

  16. Derivation and differentiation of haploid human embryonic stem cells.

    Science.gov (United States)

    Sagi, Ido; Chia, Gloryn; Golan-Lev, Tamar; Peretz, Mordecai; Weissbein, Uri; Sui, Lina; Sauer, Mark V; Yanuka, Ofra; Egli, Dieter; Benvenisty, Nissim

    2016-04-07

    Diploidy is a fundamental genetic feature in mammals, in which haploid cells normally arise only as post-meiotic germ cells that serve to ensure a diploid genome upon fertilization. Gamete manipulation has yielded haploid embryonic stem (ES) cells from several mammalian species, but haploid human ES cells have yet to be reported. Here we generated and analysed a collection of human parthenogenetic ES cell lines originating from haploid oocytes, leading to the successful isolation and maintenance of human ES cell lines with a normal haploid karyotype. Haploid human ES cells exhibited typical pluripotent stem cell characteristics, such as self-renewal capacity and a pluripotency-specific molecular signature. Moreover, we demonstrated the utility of these cells as a platform for loss-of-function genetic screening. Although haploid human ES cells resembled their diploid counterparts, they also displayed distinct properties including differential regulation of X chromosome inactivation and of genes involved in oxidative phosphorylation, alongside reduction in absolute gene expression levels and cell size. Surprisingly, we found that a haploid human genome is compatible not only with the undifferentiated pluripotent state, but also with differentiated somatic fates representing all three embryonic germ layers both in vitro and in vivo, despite a persistent dosage imbalance between the autosomes and X chromosome. We expect that haploid human ES cells will provide novel means for studying human functional genomics and development.

  17. Dragons, Ladybugs, and Softballs: Girls' STEM Engagement with Human-Centered Robotics

    Science.gov (United States)

    Gomoll, Andrea; Hmelo-Silver, Cindy E.; Šabanovic, Selma; Francisco, Matthew

    2016-01-01

    Early experiences in science, technology, engineering, and math (STEM) are important for getting youth interested in STEM fields, particularly for girls. Here, we explore how an after-school robotics club can provide informal STEM experiences that inspire students to engage with STEM in the future. Human-centered robotics, with its emphasis on the…

  18. Dragons, Ladybugs, and Softballs: Girls' STEM Engagement with Human-Centered Robotics

    Science.gov (United States)

    Gomoll, Andrea; Hmelo-Silver, Cindy E.; Šabanovic, Selma; Francisco, Matthew

    2016-01-01

    Early experiences in science, technology, engineering, and math (STEM) are important for getting youth interested in STEM fields, particularly for girls. Here, we explore how an after-school robotics club can provide informal STEM experiences that inspire students to engage with STEM in the future. Human-centered robotics, with its emphasis on the…

  19. The influence of zygote pronuclear morphology on in vitro human embryo development

    Directory of Open Access Journals (Sweden)

    Lidija Križančić-Bombek

    2007-09-01

    Full Text Available Background: The selection of embryos with largest implantation potential is an important part in assisted reproduction. Besides the embryo or blastocyst morphology, selection criteria such as position and orientation of pronuclei (PN in relation to polar body positioning and the number, size and distribution of nucleolar precursor bodies (NPB have been proposed. In our study, a correlation between PN and NBP morphology with the development of early embryos (day 2 of cultivation and blastocysts (day 5 was investigated.Methods: 653 zygotes from 113 IVF (in vitro fertilization and ICSI (intracytoplasmic sperm injection patients, younger than 40 years, were assessed 18–20 hours post-insemination. Optimal zygotes (Z1 had thouching centrally located PN with equall numbers of alligned NPB. Other zygote types differred from Z1 in having scattered NPB in both PN (Z2 or alligned NPB in one PN (Z3 or in PN beeing distant from one another (Z4. For each zygote type a percentage of normal early embryos and blastocysts was calculated.Results: Among 653 assessed zygotes 21.8 % were Z1; 29.1 % Z2, 34.6 % Z3 and 14.5 % Z4. The percentage of normal early embryos decreased from Z1 to Z4 zygote type (70.4 % vs. 55.3 % vs. 59.7 % vs.45.3 %; p < 0.05 as well as the percentage of developed blastocysts (63.4 % vs. 55.3 % vs. 58.8 % vs. 43.2 %. However, the percentages of optimal blastocysts in the four groups did not differ (11.3 % vs. 11.1 % vs. 8.4 % vs. 6.3 %.Conclusions: Best grade zygotes result in batter early embryo and blastocyst development suggesting that zygote morphology can be used in combination with embryo and/or blastocyst evaluation as a method for embryo selection prior to embryo transfer.

  20. Experimental study on regulating the influence of quantum dots on the survival of murine embryo stem cells%调控量子点对小鼠胚胎干细胞活性影响的研究

    Institute of Scientific and Technical Information of China (English)

    阮静; 沈洁; 汪铮; 崔大祥

    2011-01-01

    Objective: To regulate the influence of quantum dots on the survival of murine embryo stem cells. Methods: We prepared the quantum dots by using microwave synthesis method; labeled the murine embryo stem cells in vitro with quantum dots; analyzed the influence of quantum dots on the murine embryo stem cells by using confocal microscopy and flow eytometer, such as labeling rate, viability and proliferation capability; regulated the viability and proliferation capability of murine embryo stem cells by adding ROCK inhibitor Y-27632. Results: Murine embryo stem cells had 92.5% labeled rate and 40.7% survival rate after cultured with 20 nmol· L-1 quantum dots for 24 hours, murine embryo stem cells had 20% survival rate of growth on the same culture condition after regulated by 10 μmol· L-1 Y-27632. Conclusion: The more concentration of quantum dots treated, the higher rate of murine embryo stem cells being labeled and the lower rate of murine embryo stem cells surviving. ROCK inhibitor Y-27632 could prevent murine embryo stem cells from apoptosis and increase murine embryo stem cells' bioactivity.%目的:探讨调控量子点对小鼠胚胎干细胞活性的影响.方法:通过微波合成法制备荧光性能优越的量子点,并在体外对小鼠胚胎干细胞进行标记,采用激光共聚焦显微镜和流式细胞仪观察分析量子点对小鼠胚胎干细胞标记率、活力、增殖等方面的影响,并通过ROCK抑制剂Y-27632调控小鼠胚胎干细胞的活力和增殖能力.结果:用20 nmol·L-1的量子点标记小鼠胚胎干细胞培养24 h后,小鼠胚胎干细胞的标记率达到92.5%,存活率只有40.7%;使用10 μmol·L-1 Y-27632调控量子点标记的小鼠胚胎干细胞培养24 h后,小鼠胚胎干细胞的存活率提高20%.结论:量子点的浓度越大,小鼠胚胎干细胞的标记率越高,成活率越低,添加Y-27632可以阻止量子点标记的胚胎干细胞的凋亡,明显增加胚胎干细胞的生物活性.

  1. Innervation of the sinu-atrial node and neighbouring regions in two human embryos.

    Science.gov (United States)

    Orts Llorca, F; Domenech Mateu, J M; Puerta Fonolla, J

    1979-03-01

    In human embryos of 20 to 23 mm (36 to 40 days) it is possible to identify on the right side a nerve that we may call the sinusal, which originates by several roots from the nervus vagus dexter (Figs. 1A, B, D), descending through the right ventrolateral face of the primary trachea and right bronchus (Fig. 2, arrows). Beaded in appearance, it gives a fine anastomotic branch which, passing in front of the arteria pulmonalis dextra, passes to the left side (Figs. 2B, C, D; AN). At this level it gives the large branch for the nodus sinoatrialis which, penetrating through the wall of the superior vena cava, provides a rich innervation for the nodus sinoatrialis which is already in an advanced stage of differentiation (Fig. 3, 2; Cy, D, AN). Afterwards it gives fine branches which, following the atrial fold, are distributed throughout the posterior face of the atrium dextrum (Fig. 3). It increases in diameter and, passing through the angle formed by the right pulmonary veins with the atrium dextrum, reaches the intrapericardial portion of the inferior vena cava in the vicinity of its outlet from the atrium (Fig. 3, arrows). The whole innervation is parasympathetic at the stages studied.

  2. Effects of Fluoride on Lipid Peroxidation, DNA Damage and Apoptosis in Human Embryo Hepatocytes

    Institute of Scientific and Technical Information of China (English)

    AI-GUO WANG; TAO XIA; QI-LONG CHU; MING ZHANG; FANG LIU; XUE-MIN CHEN; KE-DI YANG

    2004-01-01

    Objective To investigate the effects of fluoride on lipid peroxidation, DNA damage and apoptosis in human embryo hepatocyte L-02 cells. Methods Lipid peroxide (LPO) level, reduced glutathione (GSH) content, DNA damage, apoptosis, and cell cycle analysis were measured after in vitro cultured L-02 cells were exposed to sodium fluoride at different doses (40 μg/mL, 80 μg/mL, and 160 μg/mL) for 24 hours. Results Fluoride caused an increase of LPO levels and a decrease of GSH content in L-02 cells. There appeared to be an obvious dose-effect relationship between the fluoride concentration and the observed changes. Fluoride also caused DNA damage and apoptosis and increased the cell number in S phase of cell cycle in the cells tested. There was a statistically significant difference in DNA damage and apoptosis when comparing the high dose of fluoride treated cells with the low dose of fluoride treated cells. Conclusion Fluoride can cause lipid peroxidation, DNA damage, and apoptosis in the L-02 cell experimental model and there is a significant positive correlation between fluoride concentration and these pathological changes.

  3. Timetable for upper eyelid development in staged human embryos and fetuses.

    Science.gov (United States)

    Byun, Tae Ho; Kim, Jeong Tae; Park, Hyoung Woo; Kim, Won Kyu

    2011-05-01

    In this study, we examined the development of the upper eyelids to provide a basic understanding of gross anatomical structures and information relative to mechanisms of congenital anomalies in the upper eyelids. We studied the upper eyelids by external and histological observation in 48 human embryos and in fetuses from 5 to 36 weeks postfertilization. The upper eyelid fold began to develop at Stage 18. Upper and lower eyelids fused from the lateral cantus at Stage 22, and fusion was complete by 9 weeks of development. Mesenchymal condensations forming the orbital part of the orbicularis oculi (OO), tarsal plate, and the eyelashes and their appendages, were first seen at Week 9. Definite muscle structures of the upper eyelid, such as the orbital part of the OO and the levator palpebrae superioris and its aponeurosis, and the Müller's muscle were observed at 12 and 14 weeks, respectively. In addition, orbital septum, arterial arcade and orbital fat pad, and tarsal gland (TG) were apparent at 12, 14, and 18 weeks, respectively. Opening of the palpebral fissure was observed at Week 20. In addition, we defined the directional orientation between the levator aponeurosis and orbital septum and the growth pattern of the TG. Our results will be helpful in understanding the normal development of the upper eyelid and the origins of upper eyelid birth defects.

  4. Integrating human stem cell expansion and neuronal differentiation in bioreactors

    Directory of Open Access Journals (Sweden)

    Costa Eunice M

    2009-09-01

    Full Text Available Abstract Background Human stem cells are cellular resources with outstanding potential for cell therapy. However, for the fulfillment of this application, major challenges remain to be met. Of paramount importance is the development of robust systems for in vitro stem cell expansion and differentiation. In this work, we successfully developed an efficient scalable bioprocess for the fast production of human neurons. Results The expansion of undifferentiated human embryonal carcinoma stem cells (NTera2/cl.D1 cell line as 3D-aggregates was firstly optimized in spinner vessel. The media exchange operation mode with an inoculum concentration of 4 × 105 cell/mL was the most efficient strategy tested, with a 4.6-fold increase in cell concentration achieved in 5 days. These results were validated in a bioreactor where similar profile and metabolic performance were obtained. Furthermore, characterization of the expanded population by immunofluorescence microscopy and flow cytometry showed that NT2 cells maintained their stem cell characteristics along the bioreactor culture time. Finally, the neuronal differentiation step was integrated in the bioreactor process, by addition of retinoic acid when cells were in the middle of the exponential phase. Neurosphere composition was monitored and neuronal differentiation efficiency evaluated along the culture time. The results show that, for bioreactor cultures, we were able to increase significantly the neuronal differentiation efficiency by 10-fold while reducing drastically, by 30%, the time required for the differentiation process. Conclusion The culture systems developed herein are robust and represent one-step-forward towards the development of integrated bioprocesses, bridging stem cell expansion and differentiation in fully controlled bioreactors.

  5. A Rapid and Efficient 2D/3D Nuclear Segmentation Method for Analysis of Early Mouse Embryo and Stem Cell Image Data

    Directory of Open Access Journals (Sweden)

    Xinghua Lou

    2014-03-01

    Full Text Available Segmentation is a fundamental problem that dominates the success of microscopic image analysis. In almost 25 years of cell detection software development, there is still no single piece of commercial software that works well in practice when applied to early mouse embryo or stem cell image data. To address this need, we developed MINS (modular interactive nuclear segmentation as a MATLAB/C++-based segmentation tool tailored for counting cells and fluorescent intensity measurements of 2D and 3D image data. Our aim was to develop a tool that is accurate and efficient yet straightforward and user friendly. The MINS pipeline comprises three major cascaded modules: detection, segmentation, and cell position classification. An extensive evaluation of MINS on both 2D and 3D images, and comparison to related tools, reveals improvements in segmentation accuracy and usability. Thus, its accuracy and ease of use will allow MINS to be implemented for routine single-cell-level image analyses.

  6. Human dental pulp stem cells and gingival fibroblasts seeded into silk fibroin scaffolds have the same ability in attracting vessels

    Directory of Open Access Journals (Sweden)

    Anna eWoloszyk

    2016-04-01

    Full Text Available Neovascularization is one of the most important processes during tissue repair and regeneration. Current healing approaches based on the use of biomaterials combined with stem cells in critical-size bone defects fail due to the insufficient implant vascularization and integration into the host tissues. Therefore, here we studied the attraction, ingrowth, and distribution of blood vessels from the chicken embryo chorioallantoic membrane into implanted silk fibroin scaffolds seeded with either human dental pulp stem cells or human gingival fibroblasts. Perfusion capacity was evaluated by non-invasive in vivo Magnetic Resonance Imaging while the number and density of blood vessels were measured by histomorphometry. Our results demonstrate that human dental pulp stem cells and gingival fibroblasts possess equal abilities in attracting vessels within silk fibroin scaffolds. Additionally, the prolonged in vitro pre-incubation period of these two cell populations favors the homogeneous distribution of vessels within silk fibroin scaffolds, which further improves implant survival and guarantees successful healing and regeneration.

  7. Xeno-free culture of human pluripotent stem cells.

    Science.gov (United States)

    Bergström, Rosita; Ström, Susanne; Holm, Frida; Feki, Anis; Hovatta, Outi

    2011-01-01

    Stem cell culture systems that rely on undefined animal-derived components introduce variability to the cultures and complicate their therapeutic use. The derivation of human embryonic stem cells and the development of methods to produce induced pluripotent stem cells combined with their potential to treat human diseases have accelerated the drive to develop xenogenic-free, chemically defined culture systems that support pluripotent self-renewal and directed differentiation. In this chapter, we describe four xeno-free culture systems that have been successful in supporting undifferentiated growth of hPSCs as well as methods for xeno-free subculture and cryopreservation of hPSCs. Each culture system consists of a xeno-free growth medium and xeno-free substratum: (1) TeSR2™ with human recombinant laminin (LN-511); (2) NutriStem™ with LN-511; (3) RegES™ with human foreskin fibroblasts (hFFs); (4) KO-SR Xeno-Free™/GF cocktail with CELLstart™ matrix.

  8. Identification of a candidate stem cell in human gallbladder.

    Science.gov (United States)

    Manohar, Rohan; Li, Yaming; Fohrer, Helene; Guzik, Lynda; Stolz, Donna Beer; Chandran, Uma R; LaFramboise, William A; Lagasse, Eric

    2015-05-01

    There are currently no reports of identification of stem cells in human gallbladder. The differences between human gallbladder and intrahepatic bile duct (IHBD) cells have also not been explored. The goals of this study were to evaluate if human fetal gallbladder contains a candidate stem cell population and if fetal gallbladder cells are distinct from fetal IHBD cells. We found that EpCAM+CD44+CD13+ cells represent the cell population most enriched for clonal self-renewal from primary gallbladder. Primary EpCAM+CD44+CD13+ cells gave rise to EpCAM+CD44+CD13+ and EpCAM+CD44+CD13- cells in vitro, and gallbladder cells expanded in vitro exhibited short-term engraftment in vivo. Last, we found that CD13, CD227, CD66, CD26 and CD49b were differentially expressed between gallbladder and IHBD cells cultured in vitro indicating clear phenotypic differences between the two cell populations. Microarray analyses of expanded cultures confirmed that both cell types have unique transcriptional profiles with predicted functional differences in lipid, carbohydrate, nucleic acid and drug metabolism. In conclusion, we have isolated a distinct clonogenic population of epithelial cells from primary human fetal gallbladder with stem cell characteristics and found it to be unique compared to IHBD cells.

  9. Computational analysis of expression of human embryonic stem cell-associated signatures in tumors

    OpenAIRE

    Wang, Xiaosheng

    2011-01-01

    Background The cancer stem cell model has been proposed based on the linkage between human embryonic stem cells and human cancer cells. However, the evidences supporting the cancer stem cell model remain to be collected. In this study, we extensively examined the expression of human embryonic stem cell-associated signatures including core genes, transcription factors, pathways and microRNAs in various cancers using the computational biology approach. Results We used the class comparison analy...

  10. Computational analysis of expression of human embryonic stem cell-associated signatures in tumors

    OpenAIRE

    Wang Xiaosheng

    2011-01-01

    Abstract Background The cancer stem cell model has been proposed based on the linkage between human embryonic stem cells and human cancer cells. However, the evidences supporting the cancer stem cell model remain to be collected. In this study, we extensively examined the expression of human embryonic stem cell-associated signatures including core genes, transcription factors, pathways and microRNAs in various cancers using the computational biology approach. Results We used the class compari...

  11. Isolating nasal olfactory stem cells from rodents or humans.

    Science.gov (United States)

    Girard, Stéphane D; Devéze, Arnaud; Nivet, Emmanuel; Gepner, Bruno; Roman, François S; Féron, François

    2011-08-22

    The olfactory mucosa, located in the nasal cavity, is in charge of detecting odours. It is also the only nervous tissue that is exposed to the external environment and easily accessible in every living individual. As a result, this tissue is unique for anyone aiming to identify molecular anomalies in the pathological brain or isolate adult stem cells for cell therapy. Molecular abnormalities in brain diseases are often studied using nervous tissue samples collected post-mortem. However, this material has numerous limitations. In contrast, the olfactory mucosa is readily accessible and can be biopsied safely without any loss of sense of smell(1). Accordingly, the olfactory mucosa provides an "open window" in the adult human through which one can study developmental (e.g. autism, schizophrenia)(2-4) or neurodegenerative (e.g. Parkinson, Alzheimer) diseases(4,5). Olfactory mucosa can be used for either comparative molecular studies(4,6) or in vitro experiments on neurogenesis(3,7). The olfactory epithelium is also a nervous tissue that produces new neurons every day to replace those that are damaged by pollution, bacterial of viral infections. This permanent neurogenesis is sustained by progenitors but also stem cells residing within both compartments of the mucosa, namely the neuroepithelium and the underlying lamina propria(8-10). We recently developed a method to purify the adult stem cells located in the lamina propria and, after having demonstrated that they are closely related to bone marrow mesenchymal stem cells (BM-MSC), we named them olfactory ecto-mesenchymal stem cells (OE-MSC)(11). Interestingly, when compared to BM-MSCs, OE-MSCs display a high proliferation rate, an elevated clonogenicity and an inclination to differentiate into neural cells. We took advantage of these characteristics to perform studies dedicated to unveil new candidate genes in schizophrenia and Parkinson's disease(4). We and others have also shown that OE-MSCs are promising candidates

  12. Timing of human preimplantation embryonic development is confounded by embryo origin

    DEFF Research Database (Denmark)

    Kirkegaard, Kirstine Kjær; Sundvall Germeys, Linda Karin M; Erlandsen, M.

    2016-01-01

    embryos from one patient as independent observations, and only very few studies that evaluate the influence from patient- and treatment-related factors on timing of development or time-lapse parameters as predictors of viability have controlled for confounding, which implies a high risk of overestimating...... these results may not be generalized to all infertile women. Not all patient-related factors were investigated. WIDER IMPLICATIONS OF THE FINDINGS Our findings underline the importance of treating embryos as dependent observations and suggest a high risk of patient-based confounding in retrospective studies....... The impact of confounders and the embryo origin needs to be addressed in order to apply appropriate statistical models in observational studies. Furthermore, this observation emphasizes the need for RCTs for evaluating use of time-lapse parameters for embryo selection. STUDY FUNDING/COMPETING INTERESTS...

  13. Altered cleavage patterns in human tripronuclear embryos and their association to fertilization method

    DEFF Research Database (Denmark)

    Joergensen, Mette Warming; Agerholm, Inge; Hindkjaer, Johnny

    2014-01-01

    PURPOSE: To analyze the cleavage patterns in dipronuclear (2PN) and tripronuclear (3PN) embryos in relation to fertilization method. METHOD: Time-lapse analysis. RESULTS: Compared to 2PN, more 3PN IVF embryos displayed early cleavage into 3 cells (p cell...... stage (p cell divisions within the cleavage cycles differed between the two groups. In contrast......, the completion of the 1st, 2nd, and 3rd cleavage cycle was delayed, but with a similar division pattern for 3PN ICSI compared with the 2PN ICSI embryos. 3PN, more often than 2PN ICSI embryos, displayed early cleavage into 3 cells (p = 0.03) and arrested development from the compaction stage and onwards (p = 0...

  14. Biology and relevance of human acute myeloid leukemia stem cells.

    Science.gov (United States)

    Thomas, Daniel; Majeti, Ravindra

    2017-03-23

    Evidence of human acute myeloid leukemia stem cells (AML LSCs) was first reported nearly 2 decades ago through the identification of rare subpopulations of engrafting cells in xenotransplantation assays. These AML LSCs were shown to reside at the apex of a cellular hierarchy that initiates and maintains the disease, exhibiting properties of self-renewal, cell cycle quiescence, and chemoresistance. This cancer stem cell model offers an explanation for chemotherapy resistance and disease relapse and implies that approaches to treatment must eradicate LSCs for cure. More recently, a number of studies have both refined and expanded our understanding of LSCs and intrapatient heterogeneity in AML using improved xenotransplant models, genome-scale analyses, and experimental manipulation of primary patient cells. Here, we review these studies with a focus on the immunophenotype, biological properties, epigenetics, genetics, and clinical associations of human AML LSCs and discuss critical questions that need to be addressed in future research. © 2017 by The American Society of Hematology.

  15. Modelling familial dysautonomia in human induced pluripotent stem cells

    OpenAIRE

    Lee, Gabsang; Studer, Lorenz

    2011-01-01

    Induced pluripotent stem (iPS) cells have considerable promise as a novel tool for modelling human disease and for drug discovery. While the generation of disease-specific iPS cells has become routine, realizing the potential of iPS cells in disease modelling poses challenges at multiple fronts. Such challenges include selecting a suitable disease target, directing the fate of iPS cells into symptom-relevant cell populations, identifying disease-related phenotypes and showing reversibility of...

  16. Generating trunk neural crest from human pluripotent stem cells

    OpenAIRE

    Miller Huang; Matthew L. Miller; McHenry, Lauren K.; Tina Zheng; Qiqi Zhen; Shirin Ilkhanizadeh; Conklin, Bruce R.; Bronner, Marianne E.; Weiss, William A.

    2016-01-01

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior “cranial” NCC form craniofacial bone, whereas solely posterior “trunk” NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typi...

  17. Non-invasive Imaging of Human Embryonic Stem Cells

    OpenAIRE

    Hong, Hao; Yang, Yunan; Zhang, Yin; Cai, Weibo

    2010-01-01

    Human embryonic stem cells (hESCs) hold tremendous therapeutic potential in a variety of diseases. Over the last decade, non-invasive imaging techniques have proven to be of great value in tracking transplanted hESCs. This review article will briefly summarize the various techniques used for non-invasive imaging of hESCs, which include magnetic resonance imaging (MRI), bioluminescence imaging (BLI), fluorescence, single-photon emission computed tomography (SPECT), positron emission tomography...

  18. Oct4 expression in adult human stem cells: evidence in support of the stem cell theory of carcinogenesis.

    Science.gov (United States)

    Tai, Mei-Hui; Chang, Chia-Cheng; Kiupel, Matti; Webster, Joshua D; Olson, L Karl; Trosko, James E

    2005-02-01

    The Oct3/4 gene, a POU family transcription factor, has been noted as being specifically expressed in embryonic stem cells and in tumor cells but not in cells of differentiated tissues. With the ability to isolate adult human stem cells it became possible to test for the expression of Oct3/4 gene in adult stem cells and to test the stem cell theory of carcinogenesis. Using antibodies and PCR primers we tested human breast, liver, pancreas, kidney, mesenchyme and gastric stem cells, the cancer cell lines HeLa and MCF-7 and human, dog and rat tumors for Oct4 expression. The results indicate that adult human stem cells, immortalized non-tumorigenic cells and tumor cells and cell lines, but not differentiated cells, express Oct4. Oct4 is expressed in a few cells found in the basal layer of human skin epidermis. The data demonstrate that adult stem cells maintain expression of Oct4, consistent with the stem cell hypothesis of carcinogenesis.

  19. Effect of Reishi polysaccharides on human stem/progenitor cells.

    Science.gov (United States)

    Chen, Wan-Yu; Yang, Wen-Bin; Wong, Chi-Huey; Shih, Daniel Tzu-Bi

    2010-12-15

    The polysaccharide fraction of Ganoderma lucidum (F3) was found to benefit our health in many ways by influencing the activity of tissue stem/progenitor cells. In this study, F3 was found to promote the adipose tissue MSCs' aggregation and chondrosphere formation, with the increase of CAM (N-CAM, I-CAM) expressions and autokine (BMP-2, IL-11, and aggrecan) secretions, in an in vitro chondrogenesis assay. In a stem cell expansion culture, it possesses the thrombopoietin (TPO) and GM-CSF like functions to enhance the survival/renewal abilities of primitive hematopoietic stem/progenitor cells (HSCs). F3 was found to promote the dendrite growth of blood mononuclear cells (MNCs) and the expression of cell adhesion molecules in the formation of immature dendritic cells (DC). On the other hand, F3 exhibited inhibitory effects on blood endothelial progenitor (EPC) colony formation, with concomitant reduction of cell surface endoglin (CD105) and vascular endothelial growth factor receptor-3 (VEGFR-3) marker expressions, in the presence of angiogenic factors. A further cytokine array analysis revealed that F3 indeed inhibited the angiogenin synthesis and enhanced IL-1, MCP-1, MIP-1, RANTES, and GRO productions in the blood EPC derivation culture. Collectively, we have demonstrated that the polysaccharide fraction of G. lucidum F3 exhibits cytokine and chemokine like functions which are beneficial to human tissue stem/progenitor cells by modulating their CAM expressions and biological activities. These findings provide us a better the observation that F3 glycopolysaccharides indeed possesses anti-angiogenic and immune-modulating functions and promotes hematopoietic stem/progenitor cell homing for better human tissue protection, reducing disease progression and health.

  20. Neuropharmacological properties of neurons derived from human stem cells.

    Science.gov (United States)

    Coyne, Leanne; Shan, Mu; Przyborski, Stefan A; Hirakawa, Ryoko; Halliwell, Robert F

    2011-09-01

    Human pluripotent stem cells have enormous potential value in neuropharmacology and drug discovery yet there is little data on the major classes and properties of receptors and ion channels expressed by neurons derived from these stem cells. Recent studies in this lab have therefore used conventional patch-clamp electrophysiology to investigate the pharmacological properties of the ligand and voltage-gated ion channels in neurons derived and maintained in vitro from the human stem cell (hSC) line, TERA2.cl.SP12. TERA2.cl.SP12 stem cells were differentiated with retinoic acid and used in electrophysiological experiments 28-50 days after beginning differentiation. HSC-derived neurons generated large whole cell currents with depolarizing voltage steps (-80 to 30 mV) comprised of an inward, rapidly inactivating component and a delayed, slowly deactivating outward component. The fast inward current was blocked by the sodium channel blocker tetrodotoxin (0.1 μM) and the outward currents were significantly reduced by tetraethylammonium ions (TEA, 5 mM) consistent with the presence of functional Na and K ion channels. Application of the inhibitory neurotransmitters, GABA (0.1-1000 μM) or glycine (0.1-1000 μM) evoked concentration dependent currents. The GABA currents were inhibited by the convulsants, picrotoxin (10 μM) and bicuculline (3 μM), potentiated by the NSAID mefenamic acid (10-100 μM), the general anaesthetic pentobarbital (100 μM), the neurosteroid allopregnanolone and the anxiolytics chlordiazepoxide (10 μM) and diazepam (10 μM) all consistent with the expression of GABA(A) receptors. Responses to glycine were reversibly blocked by strychnine (10 μM) consistent with glycine-gated chloride channels. The excitatory agonists, glutamate (1-1000 μM) and NMDA (1-1000 μM) activated concentration-dependent responses from hSC-derived neurons. Glutamate currents were inhibited by kynurenic acid (1 mM) and NMDA responses were blocked by MgCl(2) (2 mM) in a

  1. Directed Differentiation of Human Pluripotent Stem Cells to Microglia

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    Panagiotis Douvaras

    2017-06-01

    Full Text Available Microglia, the immune cells of the brain, are crucial to proper development and maintenance of the CNS, and their involvement in numerous neurological disorders is increasingly being recognized. To improve our understanding of human microglial biology, we devised a chemically defined protocol to generate human microglia from pluripotent stem cells. Myeloid progenitors expressing CD14/CX3CR1 were generated within 30 days of differentiation from both embryonic and induced pluripotent stem cells (iPSCs. Further differentiation of the progenitors resulted in ramified microglia with highly motile processes, expressing typical microglial markers. Analyses of gene expression and cytokine release showed close similarities between iPSC-derived (iPSC-MG and human primary microglia as well as clear distinctions from macrophages. iPSC-MG were able to phagocytose and responded to ADP by producing intracellular Ca2+ transients, whereas macrophages lacked such response. The differentiation protocol was highly reproducible across several pluripotent stem cell lines.

  2. Enriched retinal ganglion cells derived from human embryonic stem cells

    Science.gov (United States)

    Gill, Katherine P.; Hung, Sandy S. C.; Sharov, Alexei; Lo, Camden Y.; Needham, Karina; Lidgerwood, Grace E.; Jackson, Stacey; Crombie, Duncan E.; Nayagam, Bryony A.; Cook, Anthony L.; Hewitt, Alex W.; Pébay, Alice; Wong, Raymond C. B.

    2016-01-01

    Optic neuropathies are characterised by a loss of retinal ganglion cells (RGCs) that lead to vision impairment. Development of cell therapy requires a better understanding of the signals that direct stem cells into RGCs. Human embryonic stem cells (hESCs) represent an unlimited cellular source for generation of human RGCs in vitro. In this study, we present a 45-day protocol that utilises magnetic activated cell sorting to generate enriched population of RGCs via stepwise retinal differentiation using hESCs. We performed an extensive characterization of these stem cell-derived RGCs by examining the gene and protein expressions of a panel of neural/RGC markers. Furthermore, whole transcriptome analysis demonstrated similarity of the hESC-derived RGCs to human adult RGCs. The enriched hESC-RGCs possess long axons, functional electrophysiological profiles and axonal transport of mitochondria, suggestive of maturity. In summary, this RGC differentiation protocol can generate an enriched population of functional RGCs from hESCs, allowing future studies on disease modeling of optic neuropathies and development of cell therapies. PMID:27506453

  3. Generation of human melanocytes from induced pluripotent stem cells.

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    Shigeki Ohta

    Full Text Available Epidermal melanocytes play an important role in protecting the skin from UV rays, and their functional impairment results in pigment disorders. Additionally, melanomas are considered to arise from mutations that accumulate in melanocyte stem cells. The mechanisms underlying melanocyte differentiation and the defining characteristics of melanocyte stem cells in humans are, however, largely unknown. In the present study, we set out to generate melanocytes from human iPS cells in vitro, leading to a preliminary investigation of the mechanisms of human melanocyte differentiation. We generated iPS cell lines from human dermal fibroblasts using the Yamanaka factors (SOX2, OCT3/4, and KLF4, with or without c-MYC. These iPS cell lines were subsequently used to form embryoid bodies (EBs and then differentiated into melanocytes via culture supplementation with Wnt3a, SCF, and ET-3. Seven weeks after inducing differentiation, pigmented cells expressing melanocyte markers such as MITF, tyrosinase, SILV, and TYRP1, were detected. Melanosomes were identified in these pigmented cells by electron microscopy, and global gene expression profiling of the pigmented cells showed a high similarity to that of human primary foreskin-derived melanocytes, suggesting the successful generation of melanocytes from iPS cells. This in vitro differentiation system should prove useful for understanding human melanocyte biology and revealing the mechanism of various pigment cell disorders, including melanoma.

  4. Comment on a proposed draft protocol for the European Convention on Biomedicine relating to research on the human embryo and fetus.

    Science.gov (United States)

    Lebech, M M

    1998-10-01

    Judge Christian Byk renders service to the Steering Committee on Bioethics of the Council of Europe (CDBI) by proposing a draft of the protocol destined to fill in a gap in international law on the status of the human embryo. This proposal, printed in a previous issue of the Journal of Medical Ethics deserves nevertheless to be questioned on important points. Is Christian Byk proposing to legalise research on human embryos not only in vitro but also in utero?

  5. 75 FR 13137 - National Institutes of Health Guidelines for Human Stem Cell Research

    Science.gov (United States)

    2010-03-18

    ... on a revision to the definition of human embryonic stem cells (hESCs) in the ``National Institutes of Health Guidelines for Human Stem Cell Research'' (Guidelines). Due to a technical problem, comments... . Comments may also be mailed to: NIH Stem Cell Guidelines, MSC 7997, 9000 Rockville Pike, Bethesda, Maryland...

  6. 75 FR 8085 - National Institutes of Health Guidelines for Human Stem Cell Research

    Science.gov (United States)

    2010-02-23

    ... revision to the definition of human embryonic stem cells (hESCs) in the ``National Institutes of Health Guidelines for Human Stem Cell Research'' (Guidelines). On July 7, 2009, NIH issued Guidelines ( http...-funded stem cell research, to establish policy and procedures under which the NIH will fund such research...

  7. A murine ESC-like state facilitates transgenesis and homologous recombination in human pluripotent stem cells

    NARCIS (Netherlands)

    C. Buecker (Christa); H.H. Chen; J.M. Polo (Jose); L. Daheron (Laurence); L. Bu (Lei); T.S. Barakat (Tahsin Stefan); P. Okwieka (Patricia); A. Porter (Andrew); J.H. Gribnau (Joost); K. Hochedlinger (Konrad); N. Geijsen (Niels)

    2010-01-01

    textabstractMurine pluripotent stem cells can exist in two functionally distinct states, LIF-dependent embryonic stem cells (ESCs) and bFGF-dependent epiblast stem cells (EpiSCs). However, human pluripotent cells so far seemed to assume only an epiblast-like state. Here we demonstrate that human iPS

  8. A Murine ESC-like State Facilitates Transgenesis and Homologous Recombination in Human Pluripotent Stem Cells

    NARCIS (Netherlands)

    Buecker, Christa; Chen, Hsu-Hsin; Polo, Jose Maria; Daheron, Laurence; Bu, Lei; Barakat, Tahsin Stefan; Okwieka, Patricia; Porter, Andrew; Gribnau, Joost; Hochedlinger, Konrad; Geijsen, Niels

    2010-01-01

    Murine pluripotent stem cells can exist in two functionally distinct states, LIF-dependent embryonic stem cells (ESCs) and bFGF-dependent epiblast stem cells (EpiSCs). However, human pluripotent cells so far seemed to assume only an epiblast-like state. Here we demonstrate that human iPSC reprogramm

  9. A murine ESC-like state facilitates transgenesis and homologous recombination in human pluripotent stem cells

    NARCIS (Netherlands)

    C. Buecker (Christa); H.H. Chen; J.M. Polo (Jose); L. Daheron (Laurence); L. Bu (Lei); T.S. Barakat (Tahsin Stefan); P. Okwieka (Patricia); A. Porter (Andrew); J.H. Gribnau (Joost); K. Hochedlinger (Konrad); N. Geijsen (Niels)

    2010-01-01

    textabstractMurine pluripotent stem cells can exist in two functionally distinct states, LIF-dependent embryonic stem cells (ESCs) and bFGF-dependent epiblast stem cells (EpiSCs). However, human pluripotent cells so far seemed to assume only an epiblast-like state. Here we demonstrate that human iPS

  10. A Murine ESC-like State Facilitates Transgenesis and Homologous Recombination in Human Pluripotent Stem Cells

    NARCIS (Netherlands)

    Buecker, Christa; Chen, Hsu-Hsin; Polo, Jose Maria; Daheron, Laurence; Bu, Lei; Barakat, Tahsin Stefan; Okwieka, Patricia; Porter, Andrew; Gribnau, Joost; Hochedlinger, Konrad; Geijsen, Niels

    2010-01-01

    Murine pluripotent stem cells can exist in two functionally distinct states, LIF-dependent embryonic stem cells (ESCs) and bFGF-dependent epiblast stem cells (EpiSCs). However, human pluripotent cells so far seemed to assume only an epiblast-like state. Here we demonstrate that human iPSC reprogramm

  11. Comparative genomics of human stem cell factor (SCF

    Directory of Open Access Journals (Sweden)

    Moein Dehbashi

    2017-03-01

    Full Text Available Stem cell factor (SCF is a critical protein with key roles in the cell such as hematopoiesis, gametogenesis and melanogenesis. In the present study a comparative analysis on nucleotide sequences of SCF was performed in Humanoids using bioinformatics tools including NCBI-BLAST, MEGA6, and JBrowse. Our analysis of nucleotide sequences to find closely evolved organisms with high similarity by NCBI-BLAST tools and MEGA6 showed that human and Chimpanzee (Pan troglodytes were placed into the same cluster. By using JBrowse, we found that SCF in Neanderthal had a single copy number similar to modern human and partly conserved nucleotide sequences. Together, the results approved the gene flow and genetics similarity of SCF among human and P. troglodytes. This may suggest that during evolution, SCF gene transferred partly intact either on the basis of sequence or function from the same ancestors to P. troglodytes, the ancient human like Neanderthal, and then to the modern human.

  12. Differentiated human stem cells resemble fetal, not adult, β cells.

    Science.gov (United States)

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  13. Revocation of European patent for neural progenitors highlights patent challenges for inventions relating to human embryonic stem cells.

    Science.gov (United States)

    Rigby, Barbara

    2013-11-01

    Cells derived from human embryonic stem cells have great therapeutic potential. Patents are key to allowing companies that develop methods of generating such cells to recuperate their investment. However, in Europe, inventions relating to the use of human embryos for commercial purposes are excluded from patentability on moral grounds. The scope of this morality exclusion was recently tested before Germany's highest court and before the European Patent Office (EPO), with diverging results. The decision by the EPO's Opposition Division to revoke EP1040185 relating to neural precursors and methods for their generation has received a mixed reception. The decision has very recently been appealed, and the outcome of this Appeal should provide more definitive guidance on the scope of the morality exclusion.

  14. Efficient engineering of vascularized ectopic bone from human embryonic stem cell-derived mesenchymal stem cells.

    Science.gov (United States)

    Domev, Hagit; Amit, Michal; Laevsky, Ilana; Dar, Ayelet; Itskovitz-Eldor, Joseph

    2012-11-01

    Human mesenchymal stem cells (hMSCs) can be derived from various adult and fetal tissues. However, the quality of tissues for the isolation of adult and fetal hMSCs is donor dependent with a nonreproducible yield. In addition, tissue engineering and cell therapy require large-scale production of a pure population of lineage-restricted stem cells that can be easily induced to differentiate into a specific cell type. Therefore, human embryonic stem cells (hESCs) can provide an alternative, plentiful source for generation of reproducible hMSCs. We have developed efficient differentiation protocols for derivation of hMSCs from hESCs, including coculture with murine OP9 stromal cells and feeder layer-free system. Our protocols have resulted in the generation of up to 49% of hMSCs, which expressed CD105, CD90, CD29, and CD44. The hMSCs exhibited high adipogenic, chondrocytic, and osteogenic differentiation in vitro. The latter correlated with osteocalcin secretion and vascular endothelial growth factor (VEGF) production by the differentiating hMSCs. hMSC-derived osteoblasts further differentiated and formed ectopic bone in vivo, and induced the formation of blood vessels in Matrigel implants. Our protocol enables generation of a purified population of hESC-derived MSCs, with the potential of differentiating into several mesodermal lineages, and particularly into vasculogenesis-inducing osteoblasts, which can contribute to the development of bone repair protocols.

  15. CXCR4 activation promotes differentiation of human embryonic stem cells to neural stem cells.

    Science.gov (United States)

    Zhang, Lijun; Hua, Qiuhong; Tang, Kaiyi; Shi, Changjie; Xie, Xin; Zhang, Ru

    2016-11-19

    G protein-coupled receptors (GPCRs) are involved in many fundamental cellular responses such as growth, death, movement, transcription and excitation. Their roles in human stem cell neural specialization are not well understood. In this study, we aimed to identify GPCRs that may play a role in the differentiation of human embryonic stem cells (hESCs) to neural stem cells (NSCs). Using a feeder-free hESC neural differentiation protocol, we found that the expression of several chemokine receptors changed dramatically during the hESC/NSC transition. Especially, the expression of CXCR4 increased approximately 50 folds in NSCs compared to the original hESCs. CXCR4 agonist SDF-1 promoted, whereas the antagonist AMD3100 delayed the neural induction process. In consistence with antagonizing CXCR4, knockdown of CXCR4 in hESCs also blocked the neural induction and cells with reduced CXCR4 were rarely positive for Nestin and Sox1-staining. Taken together, our results suggest that CXCR4 is involved in the neural induction process of hESC and it might be considered as a target to facilitate NSC production from hESCs in regenerative medicine.

  16. Human induced pluripotent stem cells on autologous feeders.

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    Kazutoshi Takahashi

    Full Text Available BACKGROUND: For therapeutic usage of induced Pluripotent Stem (iPS cells, to accomplish xeno-free culture is critical. Previous reports have shown that human embryonic stem (ES cells can be maintained in feeder-free condition. However, absence of feeder cells can be a hostile environment for pluripotent cells and often results in karyotype abnormalities. Instead of animal feeders, human fibroblasts can be used as feeder cells of human ES cells. However, one still has to be concerned about the existence of unidentified pathogens, such as viruses and prions in these non-autologous feeders. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that human induced Pluripotent Stem (iPS cells can be established and maintained on isogenic parental feeder cells. We tested four independent human skin fibroblasts for the potential to maintain self-renewal of iPS cells. All the fibroblasts tested, as well as their conditioned medium, were capable of maintaining the undifferentiated state and normal karyotypes of iPS cells. Furthermore, human iPS cells can be generated on isogenic parental fibroblasts as feeders. These iPS cells carried on proliferation over 19 passages with undifferentiated morphologies. They expressed undifferentiated pluripotent cell markers, and could differentiate into all three germ layers via embryoid body and teratoma formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that autologous fibroblasts can be not only a source for iPS cells but also be feeder layers. Our results provide a possibility to solve the dilemma by using isogenic fibroblasts as feeder layers of iPS cells. This is an important step toward the establishment of clinical grade iPS cells.

  17. Expression of stem cell markers in the human fetal kidney.

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    Sally Metsuyanim

    Full Text Available In the human fetal kidney (HFK self-renewing stem cells residing in the metanephric mesenchyme (MM/blastema are induced to form all cell types of the nephron till 34(th week of gestation. Definition of useful markers is crucial for the identification of HFK stem cells. Because wilms' tumor, a pediatric renal cancer, initiates from retention of renal stem cells, we hypothesized that surface antigens previously up-regulated in microarrays of both HFK and blastema-enriched stem-like wilms' tumor xenografts (NCAM, ACVRIIB, DLK1/PREF, GPR39, FZD7, FZD2, NTRK2 are likely to be relevant markers. Comprehensive profiling of these putative and of additional stem cell markers (CD34, CD133, c-Kit, CD90, CD105, CD24 in mid-gestation HFK was performed using immunostaining and FACS in conjunction with EpCAM, an epithelial surface marker that is absent from the MM and increases along nephron differentiation and hence can be separated into negative, dim or bright fractions. No marker was specifically localized to the MM. Nevertheless, FZD7 and NTRK2 were preferentially localized to the MM and emerging tubules (50% of HFK cells and predominantly co-express EpCAM(bright, indicating they are mostly markers of differentiation. Furthermore, localization of NCAM exclusively in the MM and in its nephron progenitor derivatives but also in stroma and the expression pattern of significantly elevated renal stem/progenitor genes Six2, Wt1, Cited1, and Sall1 in NCAM(+EpCAM(- and to a lesser extent in NCAM(+EpCAM(+ fractions confirmed regional identity of cells and assisted us in pinpointing the presence of subpopulations that are putative MM-derived progenitor cells (NCAM(+EpCAM(+FZD7(+, MM stem cells (NCAM(+EpCAM(-FZD7(+ or both (NCAM(+FZD7(+. These results and concepts provide a framework for developing cell selection strategies for human renal cell-based therapies.

  18. Human pluripotent stem cell-derived limbal epithelial stem cells on bioengineered matrices for corneal reconstruction.

    Science.gov (United States)

    Mikhailova, Alexandra; Ilmarinen, Tanja; Ratnayake, Anjula; Petrovski, Goran; Uusitalo, Hannu; Skottman, Heli; Rafat, Mehrdad

    2016-05-01

    Corneal epithelium is renewed by limbal epithelial stem cells (LESCs), a type of tissue-specific stem cells located in the limbal palisades of Vogt at the corneo-scleral junction. Acute trauma or inflammatory disorders of the ocular surface can destroy these stem cells, leading to limbal stem cell deficiency (LSCD) - a painful and vision-threatening condition. Treating these disorders is often challenging and complex, especially in bilateral cases with extensive damage. Human pluripotent stem cells (hPSCs) provide new opportunities for corneal reconstruction using cell-based therapy. Here, we investigated the use of hPSC-derived LESC-like cells on bioengineered collagen matrices in serum-free conditions, aiming for clinical applications to reconstruct the corneal epithelium and partially replace the damaged stroma. Differentiation of hPSCs towards LESC-like cells was directed using small-molecule induction followed by maturation in corneal epithelium culture medium. After four to five weeks of culture, differentiated cells were seeded onto bioengineered matrices fabricated as transparent membranes of uniform thickness, using medical-grade porcine collagen type I and a hybrid cross-linking technology. The bioengineered matrices were fully transparent, with high water content and swelling capacity, and parallel lamellar microstructure. Cell proliferation of hPSC-LESCs was significantly higher on bioengineered matrices than on collagen-coated control wells after two weeks of culture, and LESC markers p63 and cytokeratin 15, along with proliferation marker Ki67 were expressed even after 30 days in culture. Overall, hPSC-LESCs retained their capacity to self-renew and proliferate, but were also able to terminally differentiate upon stimulation, as suggested by protein expression of cytokeratins 3 and 12. We propose the use of bioengineered collagen matrices as carriers for the clinically-relevant hPSC-derived LESC-like cells, as a novel tissue engineering approach for

  19. Epigenetic Regulation of Human Embryonic Stem Cells

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    Qidong eHu

    2012-11-01

    Full Text Available Recently, there has been tremendous progress in characterizing the transcriptional network regulating hESCs (MacArthur et al., 2009; Loh et al., 2011, including those signaling events mediated by Oct4, Nanog and Sox2. There is growing interest in the epigenetic machinery involved in hESC self-renewal and differentiation. In general, epigenetic regulation includeschromatin reorganization, DNA modification and histone modification, which are not directly related to alterations in DNA sequences. Various protein complexes, includingPolycomb, trithorax, NuRD, SWI/SNF andOct4, have been shown to play critical roles in epigenetic control of hESC maintenance and differentiation. Hence, we will formally review recent advances in unraveling the multifaceted role of epigenetic regulation in hESC self-renewal and induced differentiation, particularly with respect to chromatin remodeling and DNA methylation events. Unraveling the molecular mechanisms underlying the maintenance/differentiation of hESCs and reprogramming of somatic cells will greatly strengthen our capacity to generate various types of cells to treat human diseases.

  20. New President, New Human Embryonic Stem Cell Research Policy: Comparative International Perspectives and Embryonic Stem Cell Research Laws in France*

    Science.gov (United States)

    Drabiak-Syed, By Katherine

    2013-12-01

    This article provides an overview of French legislative history, Parliamentary debates, and recent amendments in hESC research policy, as well as additional comparisons with laws across the European Union. Unlike policy discussions in the U.S., French dialogue on hESC research generally rejects the arbitrary division between the status of the embryo and hESCs, recognizing that hESC research necessarily requires the destruction of human embryos. Accordingly, French discourse debates the competing interests of science with secular ethical and civic considerations relating to the symbolic status of the embryo and society's duty to moderate what constitutes appropriate boundaries on research. Parliament recently amended France's hESC research laws to explicitly permit hESC research, signaling the beginning of reform efforts under President Hollande's new power structure, but the inclusion of secular moral considerations in the policy debate will likely restrain the extent of any future changes.

  1. Human Brain Stem Structures Respond Differentially to Noxious Heat

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    Alexander eRitter

    2013-09-01

    Full Text Available Concerning the physiological correlates of pain, the brain stem is considered to be one core region that is activated by noxious input. In animal studies, different slopes of skin heating (SSH with noxious heat led to activation in different columns of the midbrain periaqueductal grey (PAG. The present study aimed at finding a method for differentiating structures in PAG and other brain stem structures, which are associated with different qualities of pain in humans according to the structures that were associated with different behavioral significances to noxious thermal stimulation in animals. Brain activity was studied by fMRI in healthy subjects in response to steep and shallow SSH with noxious heat. We found differential activation to different SSH in the PAG and the rostral ventromedial medulla (RVM. In a second experiment we demonstrate that the different SSH were associated with different pain qualities. Our experiments provide evidence that brainstem structures, i.e. the PAG and the RVM, become differentially activated by different SSH. Therefore, different SSH can be utilized when brain stem structures are investigated and when it is aimed to activate these structures differentially. Moreover, percepts of first pain were elicited by shallow SSH whereas percepts of second pain were elicited by steep SSH. The stronger activation of these brain stem structures to SSH, eliciting percepts of second vs. first pain, might be of relevance for activating different coping strategies in response to the noxious input with the two types of SSH.

  2. Generation of mature hematopoietic cells from human pluripotent stem cells.

    Science.gov (United States)

    Togarrati, Padma Priya; Suknuntha, Kran

    2012-06-01

    A number of malignant and non-malignant hematological disorders are associated with the abnormal production of mature blood cells or primitive hematopoietic precursors. Their capacity for continuous self-renewal without loss of pluripotency and the ability to differentiate into adult cell types from all three primitive germ layers make human embryonic stem cells and induced pluripotent stem cells (hiPSCs) attractive complementary cell sources for large-scale production of transfusable mature blood cell components in cell replacement therapies. The generation of patient-specific hematopoietic stem/precursor cells from iPSCs by the regulated manipulation of various factors involved in reprograming to ensure complete pluripotency, and developing innovative differentiation strategies for generating unlimited supply of clinically safe, transplantable, HLA-matched cells from hiPSCs to outnumber the inadequate source of hematopoietic stem cells obtained from cord blood, bone marrow and peripheral blood, would have a major impact on the field of regenerative and personalized medicine leading to translation of these results from bench to bedside.

  3. HIF induces human embryonic stem cell markers in cancer cells.

    Science.gov (United States)

    Mathieu, Julie; Zhang, Zhan; Zhou, Wenyu; Wang, Amy J; Heddleston, John M; Pinna, Claudia M A; Hubaud, Alexis; Stadler, Bradford; Choi, Michael; Bar, Merav; Tewari, Muneesh; Liu, Alvin; Vessella, Robert; Rostomily, Robert; Born, Donald; Horwitz, Marshall; Ware, Carol; Blau, C Anthony; Cleary, Michele A; Rich, Jeremy N; Ruohola-Baker, Hannele

    2011-07-01

    Low oxygen levels have been shown to promote self-renewal in many stem cells. In tumors, hypoxia is associated with aggressive disease course and poor clinical outcomes. Furthermore, many aggressive tumors have been shown to display gene expression signatures characteristic of human embryonic stem cells (hESC). We now tested whether hypoxia might be responsible for the hESC signature observed in aggressive tumors. We show that hypoxia, through hypoxia-inducible factor (HIF), can induce an hESC-like transcriptional program, including the induced pluripotent stem cell (iPSC) inducers, OCT4, NANOG, SOX2, KLF4, cMYC, and microRNA-302 in 11 cancer cell lines (from prostate, brain, kidney, cervix, lung, colon, liver, and breast tumors). Furthermore, nondegradable forms of HIFα, combined with the traditional iPSC inducers, are highly efficient in generating A549 iPSC-like colonies that have high tumorigenic capacity. To test potential correlation between iPSC inducers and HIF expression in primary tumors, we analyzed primary prostate tumors and found a significant correlation between NANOG-, OCT4-, and HIF1α-positive regions. Furthermore, NANOG and OCT4 expressions positively correlated with increased prostate tumor Gleason score. In primary glioma-derived CD133 negative cells, hypoxia was able to induce neurospheres and hESC markers. Together, these findings suggest that HIF targets may act as key inducers of a dynamic state of stemness in pathologic conditions.

  4. Proof of concept studies exploring the safety and functional activity of human parthenogenetic-derived neural stem cells for the treatment of Parkinson's disease.

    Science.gov (United States)

    Gonzalez, Rodolfo; Garitaonandia, Ibon; Crain, Andrew; Poustovoitov, Maxim; Abramihina, Tatiana; Noskov, Alexander; Jiang, Chuan; Morey, Robert; Laurent, Louise C; Elsworth, John D; Snyder, Evan Y; Redmond, D Eugene; Semechkin, Ruslan

    2015-01-01

    Recent studies indicate that human pluripotent stem cell (PSC)-based therapies hold great promise in Parkinson's disease (PD). Clinical studies have shown that grafted fetal neural tissue can achieve considerable biochemical and clinical improvements in PD. However, the source of fetal tissue grafts is limited and ethically controversial. Human parthenogenetic stem cells offer a good alternative because they are derived from unfertilized oocytes without destroying viable human embryos and can be used to generate an unlimited supply of neural stem cells for transplantation. Here we evaluate for the first time the safety and engraftment of human parthenogenetic stem cell-derived neural stem cells (hpNSCs) in two animal models: 6-hydroxydopamine (6-OHDA)-lesioned rodents and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated nonhuman primates (NHPs). In both rodents and nonhuman primates, we observed successful engraftment and higher dopamine levels in hpNSC-transplanted animals compared to vehicle control animals, without any adverse events. These results indicate that hpNSCs are safe, well tolerated, and could potentially be a source for cell-based therapies in PD.

  5. Location and expression of neurotrophin-3 and its receptor in the brain of human embryos during early development

    Institute of Scientific and Technical Information of China (English)

    Jian Li; Yongjie Mi; Dajun Ma

    2008-01-01

    BACKGROUND: Cell culture in vitro trials have demonstrated that neurotrophin-3 (NT-3) can enhance the survival of sensory neurons and sympathetic neurons, and can also support embryo-derived motor neurons.This effect is dependent on nerve growth factor on the surface of cells. Understanding the role of NT-3 and its receptor in the early development of human embryonic brains will help to investigate the correlation between early survival of nerve cells and the microenvironment of neural regeneration.OBJECTIVE: To observe the proliferation of cerebral neurons in the development of human embryonic brain, and to investigate the location, expression and distribution of NT-3 and its receptor TrkC during human brain development.DESIGN, TIME AND SETTING: An observation study on cells was performed in the Department of Human Anatomy, Histology and Embryology, Chengdu Medical College in September 2007.MATERIALS: Fifteen specimens of fresh human embryo, aged 6 weeks, were used in this study.METHODS: The proliferation of cerebral neurons was detected using proliferating cell nuclear antigen, and the immunocytochemistry ABC technique was applied to observe the location, expression and distribution of NT-3 and its receptor TrkC in the brain of the human embryo.MAIN OUTCOME MEASURES: Location, expression and distribution of NT-3 and its receptor in the brain of the human embryo.RESULTS: In the early period (aged 6 weeks) of human embryonic development, proliferating cell nuclear antigen-positive reactive substances were mainly observed in the nucleus of the forebrain ventricular zone and subventricular zone, and the intensity was stronger in the subventricular zone than the forebrain ventricle.NT-3 positive reactive substance was mainly distributed in the cytoblastema of the forebrain neuroepithelial layer and nerve cell process, while TrkC was mainly distributed in the cell membrane of the forebrain ventricular zone and subventricular zone. During embryonic development, NT-3 and

  6. A zebrafish xenograft model for studying human cancer stem cells in distant metastasis and therapy response.

    Science.gov (United States)

    Chen, L; Groenewoud, A; Tulotta, C; Zoni, E; Kruithof-de Julio, M; van der Horst, G; van der Pluijm, G; Ewa Snaar-Jagalska, B

    2017-01-01

    Lethal and incurable bone metastasis is one of the main causes of death in multiple types of cancer. A small subpopulation of cancer stem/progenitor-like cells (CSCs), also known as tumor-initiating cells from heterogenetic cancer is considered to mediate bone metastasis. Although over the past decades numerous studies have been performed in different types of cancer, it is still difficult to track small numbers of CSCs during the onset of metastasis. With use of noninvasive high-resolution imaging, transparent zebrafish embryos can be employed to dynamically visualize cancer progression and reciprocal interaction with stroma in a living organism. Recently we established a zebrafish CSC-xenograft model to visually and functionally analyze the role of CSCs and their interactions with the microenvironment at the onset of metastasis. Given the highly conserved human and zebrafish genome, transplanted human cancer cells are able to respond to zebrafish cytokines, modulate the zebrafish microenvironment, and take advantage of the zebrafish stroma during cancer progression. This chapter delineates the zebrafish CSC-xenograft model as a useful tool for both CSC biological study and anticancer drug screening. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. RETRACTION - In Vitro Derivation of Human Sperm from Embryonic Stem Cells.

    Science.gov (United States)

    Nayernia, Karim; Lee, Jae Ho; Lako, Majlinda; Armstrong, Lyle; Herbert, Mary; Li, Manyu; Engel, Wolfgang; Elliott, David; Stojkovic, Miodrag; Parrington, John; Murdoch, Alison; Strachan, Tom; Zhang, Xin

    2009-07-07

    This article, "In Vitro Derivation of Human Sperm from Embryonic