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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.     

Engraftable neural crest stem cells derived from cynomolgus monkey embryonic stem cells

Neural crest stem cells (NCSCs), a population of multipotent cells that migrate extensively and give rise to diverse derivatives, including peripheral and enteric neurons and glia, craniofacial cartilage and bone, melanocytes and smooth muscle, have great potential for regenerative medicine. Non-human primates provide optimal models for the development of stem cell therapies. Here, we describe the first derivation of NCSCs from cynomolgus monkey embryonic stem cells (CmESCs) at the neural rosette stage. CmESC-derived neurospheres replated on polyornithine/laminin-coated dishes migrated onto the substrate and showed characteristic expression of NCSC markers, including Sox10, AP2α, Slug, Nestin, p75, and HNK1. CmNCSCs were capable of propagating in an undifferentiated state in vitro as adherent or suspension cultures, and could be subsequently induced to differentiate towards peripheral nervous system lineages (peripheral sympathetic neurons, sensory neurons, and Schwann cells) and mesenchymal lineages (osteoblasts, adipocytes, chondrocytes, and smooth muscle cells). CmNCSCs transplanted into developing chick embryos or fetal brains of cynomolgus macaques survived, migrated, and differentiated into progeny consistent with a neural crest identity. Our studies demonstrate that CmNCSCs offer a new tool for investigating neural crest development and neural crest-associated human disease and suggest that this non-human primate model may facilitate tissue engineering and regenerative medicine efforts.     

Identification and characterization of hemoangiogenic progenitors during cynomolgus monkey embryonic stem cell differentiation

We identified intermediate-stage progenitor cells that have the potential to differentiate into hematopoietic and endothelial lineages from nonhuman primate embryonic stem (ES) cells. Sequential fluorescence-activated cell sorting and immunostaining analyses showed that when ES cells were cultured in an OP9 coculture system, both lineages developed after the emergence of two hemoangiogenic progenitor-bearing cell fractions, namely, vascular endothelial growth factor receptor (VEGFR)-2(high) CD34(-) and VEGFR-2(high) CD34(+) cells. Exogenous vascular endothelial growth factor increased the proportion of VEGFR-2(high) cells, particularly that of VEGFR-2(high) CD34(+) cells, in a dose-dependent manner. Although either population of VEGFR-2(high) cells could differentiate into primitive and definitive hematopoietic cells (HCs), as well as endothelial cells (ECs), the VEGFR-2(high) CD34(+) cells had greater hemoangiogenic potential. Both lineages developed from VEGFR-2(high) CD34(-)or VEGFR-2(high) CD34(+) precursor at the single-cell level, which strongly supports the existence of hemangioblasts in these cell fractions. Thus, this culture system allows differentiation into the HC and EC lineages to be defined by surface markers. These observations should facilitate further studies both on early developmental processes and on regeneration therapies in human.     

Laser-assisted derivation of human embryonic stem cell lines from IVF embryos after preimplantation genetic diagnosis

BACKGROUND: Human embryonic stem cells (hESCs) suitable for future transplantation therapy should preferably be developed in an animal-free system. Our objective was to develop a laser-based system for the isolation of the inner cell mass (ICM) that can develop into hESC lines, thereby circumventing immunosurgery that utilizes animal products. METHODS: Hatching was assisted by micromanipulation techniques through a laser-drilled orifice in the zona pellucida of 13 abnormal preimplantation genetic diagnosed blastocysts. ICMs were dissected from the trophectoderm by a laser beam and plated on feeders to derive hESC lines. RESULTS: eight ICMs were isolated from nine hatched blastocysts and gave rise to three hESC lines affected by myotonic dystrophy type 1, hemophilia A and a carrier of cystic fibrosis 405 + 1G > A mutation. Five blastocysts that collapsed during assisted hatching or ICM dissection were plated whole, giving rise to an additional line affected by fragile X. All cell lines expressed markers of pluripotent stem cells and differentiated in vitro and in vivo into the three germ layers. CONCLUSIONS: These hESC lines can serve as an important model of the genetic disorders that they carry. Laser-assisted isolation of the ICMs may be applied for the derivation of new hESC lines in a xeno-free system for future clinical applications.     

Isolation and characterization of novel rhesus monkey embryonic stem cell lines

ESCs are important as research subjects since the mechanisms underlying cellular differentiation, expansion, and self-renewal can be studied along with differentiated tissue development and regeneration in vitro. Furthermore, human ESCs hold promise for cell and tissue replacement approaches to treating human diseases. The rhesus monkey is a clinically relevant primate model that will likely be required to bring these clinical applications to fruition. Monkey ESCs share a number of properties with human ESCs, and their derivation and use are not affected by bioethical concerns. Here, we summarize our experience in the establishment of 18 ESC lines from rhesus monkey preimplantation embryos generated by the application of the assisted reproductive technologies. The newly derived monkey ESC lines were maintained in vitro without losing their chromosomal integrity, and they expressed markers previously reported present in human and monkey ESCs. We also describe initial efforts to compare the pluripotency of ESC lines by expression profiling, chimeric embryo formation, and in vitro-directed differentiation into endodermal, mesodermal, and ectodermal lineages.     

Establishment of human embryonic stem cell lines and their therapeutic application

Embryonic stem (ES) cell lines are pluripotent stem cell lines that can be propagated indefinitely in culture, retaining their potency to differentiate into every type of cell and tissue in the body. ES cell lines were first established from mouse blastocysts, and have been used for research in developmental biology. ES cells have been proven to be very valuable in the genetic modification of the mouse, especially in producing knockout mice. Since establishment of human ES cell lines was reported, their use in cell replacement therapies has been enthusiastically expected. There have been reports of the differentiation of several useful cell types from human ES cell lines, and clinical use of functional tissues and cells from human ES cells is anticipated. In Japan, there have also been many demands for the use of human ES cells in basic and pre-clinical research. We obtained governmental permission to establish human ES cell lines in April 2002 and started research using donated frozen embryos in January 2003. We successfully established three ES cell line from three blastocysts. These cell lines will be distributed at cost to researchers who have governmental permission to use human ES cells.     

Establishment of the gene-inducible system in primate embryonic stem cell lines

Human embryonic stem cells (ESCs) would provide a potentially unlimited source for cell replacement therapies. However, the molecular mechanisms involved in the maintenance of "stemness" are not fully understood. Monkey ESCs are much more similar in character to human ESCs than are mouse ESCs. Therefore, studies using monkey ESCs can give conclusions that are more relevant and may be readily applicable to both basic research and clinical applications for future regenerative medicine. For such studies, generation of a gene-inducible system regulatable in primate ESCs would serve as a powerful tool. Here, we established a Tet-Off gene-inducible system in monkey ESC lines. Such manipulated cells maintained ESC characteristics, and inducible gene expression in both the stem cells and differentiated cells could be reliably controlled by doxycycline administration.     

Multilineage differentiation from human embryonic stem cell lines

Stem cells are unique cell populations with the ability to undergo both self-renewal and differentiation. A wide variety of adult mammalian tissues harbors stem cells, yet "adult" stem cells may be capable of developing into only a limited number of cell types. In contrast, embryonic stem (ES) cells, derived from blastocyst-stage early mammalian embryos, have the ability to form any fully differentiated cell of the body. Human ES cells have a normal karyotype, maintain high telomerase activity, and exhibit remarkable long-term proliferative potential, providing the possibility for unlimited expansion in culture. Furthermore, they can differentiate into derivatives of all three embryonic germ layers when transferred to an in vivo environment. Data are now emerging that demonstrate human ES cells can initiate lineage-specific differentiation programs of many tissue and cell types in vitro. Based on this property, it is likely that human ES cells will provide a useful differentiation culture system to study the mechanisms underlying many facets of human development. Because they have the dual ability to proliferate indefinitely and differentiate into multiple tissue types, human ES cells could potentially provide an unlimited supply of tissue for human transplantation. Though human ES cell-based transplantation therapy holds great promise to successfully treat a variety of diseases (e.g., Parkinson's disease, diabetes, and heart failure) many barriers remain in the way of successful clinical trials.     

Derivation of human embryonic stem cell lines from embryos obtained after IVF and after PGD for monogenic disorders

BACKGROUND: Human embryonic stem (hES) cells are pluripotent cells usually derived from the inner cell mass (ICM) of blastocysts. Because of their ability to differentiate into all three embryonic germ layers, hES cells represent an important material for studying developmental biology and cell replacement therapy. hES cell lines derived from blastocysts diagnosed as carrying a genetic disorder after PGD represent in vitro disease models. METHODS: ICMs isolated by immunosurgery from human blastocysts donated for research after IVF cycles and after PGD were plated in serum-free medium (except VUB01) on mouse feeder layers. RESULTS: Five hES cell lines were isolated, two from IVF embryos and three from PGD embryos. All lines behave similarly in culture and present a normal karyotype. The lines express all the markers considered characteristic of undifferentiated hES cells and were proven to be pluripotent both in vitro and in vivo (ongoing for VUB05_HD). CONCLUSIONS: We report here on the derivation of two hES cell lines presumed to be genetically normal (VUB01 and VUB02) and three hES cell lines carrying mutations for myotonic dystrophy type 1 (VUB03_DM1), cystic fibrosis (VUB04_CF) and Huntington disease (VUB05_HD).     

Human embryonic stem cell lines derived from discarded embryos

Human pluripotent embryonic stem (ES) cells have important potential in regenerative medicine and as models for human preimplantation development; however, debate continues over whether embryos should be destroyed to produce human ES cells. We have derived four ES cell lines on mouse embryonic fibroblast cells in medium supplemented with basic fibroblast growth factor, human recombinant leukemia inhibitory factor, and fetal bovine serum. The source of these cell lines was poor-quality embryos that in the course of routine clinical practice would have been discarded. After continuous proliferation in vitro for more than 12 months, these ES cell lines maintained their developmental potential to form trophoblast and somatic cells, including cardiac muscle and neuronal tissue.     

Establishment of novel embryonic stem cell lines derived from the common marmoset (Callithrix jacchus)

The successful establishment of human embryonic stem cell (hESC) lines has inaugurated a new era in regenerative medicine by facilitating the transplantation of differentiated ESCs to specific organs. However, problems with the safety and efficacy of hESC therapy in vivo remain to be resolved. Preclinical studies using animal model systems, including nonhuman primates, are essential to evaluate the safety and efficacy of hESC therapies. Previously, we demonstrated that common marmosets are suitable laboratory animal models for preclinical studies of hematopoietic stem cell therapies. As this animal model is also applicable to preclinical trials of ESC therapies, we have established novel common marmoset ESC (CMESC) lines. To obtain marmoset embryos, we developed a new embryo collection system, in which blastocysts can be obtained every 3 weeks from each marmoset pair. The inner cell mass was isolated by immunosurgery and plated on a mouse embryonic feeder layer. Some of the CMESC lines were cultured continuously for more than 1 year. These CMESC lines showed alkaline phosphatase activity and expressed stage-specific embryonic antigen (SSEA)-3, SSEA-4, TRA-1-60, and TRA-1-81. On the other hand, SSEA-1 was not detected. Furthermore, our novel CMESCs are pluripotent, as evidenced by in vivo teratoma formation in immunodeficient mice and in vitro differentiation experiments. Our established CMESC lines and the common marmoset provide an excellent experimental model system for understanding differentiation mechanisms, as well as the development of regenerative therapies using hESCs.     

Rho-associated kinase inhibitor Y-27632 promotes survival of cynomolgus monkey embryonic stem cells

Non-human primates are suitable models for preclinical research aimed at cell-replacement therapies. Recently, it has been reported that Rho-associated kinase inhibitor Y-27632 markedly reduced dissociation-induced apoptosis of human embryonic stem (hES) cells, and is expected as a novel supplement for hES cell maintenance or differentiation inductions; however, the effects of the chemical are still to be determined in model animals. Here, we demonstrated the effect of Y-27632 on cynomolgus monkey ES (cyES) cells. Also, in cyES cells, Y-27632 treatment dramatically improved the efficiency of colony formation from single cells without affecting the pluripotent state and karyotype. Y-27632 supplementation was also effective for feeder-free culture and differentiation induction. Neural stem cells directly induced from cyES cells could give rise to neurons, astrocytes and dopamine producing cells. The present result not only suggests that the chemical was effective for improving the culture system of primate ES cells, but also the similarity between cyES and hES cells regarding the reactions to the chemical, which might be further evidence that cyES cells are superior models for hES cells.     

Lymphokines produced by herpesvirus-transformed marmoset monkey lymphoid cell lines. I. Characterization of a constitutively produced interferon

Conditioned media from cultures of marmoset monkey T-lymphoid cell lines transformed by Herpesvirus saimiri or Herpesvirus ateles were found to contain interferon (IFN) activity. Titers between individual cell lines varied by a factor of 100; large amounts (up to 10(5) units/ml, assayed on human cells) were produced in one of the cell lines. IFN production was enhanced by the diterpene tumor promoters, TPA and mezerein, but not by classical T-cell mitogens. The IFN resembles human IFN-gamma by the following criteria: lability at pH 2, stability against 2-mercaptoethanol, cross-species activity, shape of dose-response curves, and molecular weight determined by size-exclusion chromatography (50,000-55,000). Its activity was not inhibited, however, by antiserum against human IFN-gamma or antisera against human IFN-alpha or IFN-beta.     

Molecular cloning and function of Oct-3 isoforms in cynomolgus monkey embryonic stem cells

Oct-3 is a key molecule for maintaining self-renewal in mouse embryonic stem (ES) cells. The function of Oct-3 in ES cells of other species, however, especially primate ES cells, is not clear. In the present study, we cloned two splicing isoforms of Oct-3, Oct-3A and Oct-3B, from cynomolgus monkey ES cells, and found that they have high homology to human Oct-3A and Oct-3B. To examine their function, Oct-3A and Oct-3B were overexpressed in cynomolgus monkey ES cells. Transient Oct-3A overexpression induced ES cell differentiation into endodermal and mesodermal lineages and disrupted proliferation of undifferentiated monkey ES cells. In contrast, Oct-3B overexpression did not induce differentiation of monkey ES cells. These findings indicate that a certain Oct-3A expression level has an important role in sustaining self-renewal in non-human primate ES cells.     

C57BL/6J×129/J杂交小鼠ES细胞系的建株(英)

 目的：建立C57BL/6J×129/J杂交小鼠ES细胞系。 方法： 收集3.5 d.p.c.的囊胚，培养在预先铺有小鼠成纤维细胞（MEFs）的高糖DMEM培养液中。3-4 d后，挑出内细胞团（ICM），消化后重新种到新鲜的有MEFS培养液中。等到有典型的ES样集落长出，即传代以得到永久ES细胞系。通过分析碱性磷酸酶活性，SSEA-1，Oct-4的表达和形成畸胎瘤的能力来鉴定ES细胞的多向分化能力。 结果： 获得的两个C57BL/6J×129/J杂交小鼠ES细胞系绝大多数细胞具有正常的核型（40，XY），碱性磷酸酶染色阳性，SSEA-1，Oct-4表达阳性， ES细胞注入SCID鼠后可获得来自3个胚层的组织。 结论： 建立了两株具有长期自我更新能力和多向分化潜能的C57BL/6J×129/J杂交小鼠ES细胞系。     

Human embryonic stem cell derivation: from the IVF perspective to therapeutic applications

Human embryonic stem cells (hESC) are capable of proliferating indefinitely in an undifferentiated state and are pluripotent, being able to differentiate into most cell types under the correct conditions. Since the establishment of the first hESC line in 1998, the hope has existed that these cells could constitute an unlimited cell source for replacement therapy in the treatment of various diseases and disabilities. However, there is opposition and concern within society towards hESC derivation. The purpose of this article is to introduce the medical and scientific issues surrounding hESC derivation for clinical use concerning the source for this research (human embryos donated from in vitro fertilization procedures), and the methodologies implicated in feeder-free, xeno-free derivation that will allow potential clinical applications.     

Horse embryonic stem cell lines from the proliferation of inner cell mass cells

Inner cell mass (ICM) cells were isolated immunosurgically from day 7-8 horse blastocysts and, after proliferation in vitro for 15-28 passages, three lines of cells were confirmed to be embryonic stem (ES) cells by their continued expression of alkaline phosphatase activity and their ability to bind antisera specific for the recognized stem cell markers, SSEA-1, TRA-1-60, TRA-1-81, and the key embryonic gene Oct-4. When maintained under feeder cell-free conditions in vitro, the three lines of cells differentiated into cells of ectodermal, endodermal, and mesodermal lineages. However, they did not form teratomata when injected into the testes of severe combined immunodeficiency (SCID)/beige immunoincompetent mice, thereby indicating a significant difference in phenotype between ES cells of the horse and those of the mouse and human.