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Featured researches published by Eric Hayes.


Stem Cell Research | 2010

Long term expansion of undifferentiated human iPS and ES cells in suspension culture using a defined medium.

Ruth Olmer; Alexandra Haase; Sylvia Merkert; Wei Cui; Jiří Paleček; Chen Ran; Andreas Kirschning; Thomas Scheper; Silke Glage; Konstantin Miller; Eliza Curnow; Eric Hayes; Ulrich Martin

Therapeutic application of stem cell derivatives requires large quantities of cells produced in defined media that cannot be produced via conventional adherent culture. We have applied human induced pluripotent stem (hiPS) cells expressing eGFP under control of the OCT4 promoter to establish the expansion of undifferentiated human embryonic stem (hES) and hiPS cells in suspension culture. A defined culture medium has been identified that results in up to six-fold increase in cell numbers within four days. Our culture system is based on initial single cell dissociation which is critical for standardized process inoculation. HES / hiPS cells were expanded for up to 17 passages. The cells maintained a stable karyotype, their expression of pluripotency markers and their potential to differentiate into derivatives of all three germ layers. The ability to expand HES / hiPS cells in a scalable suspension culture represents a critical step towards standardized production in stirred bioreactors.


Reproductive Biology and Endocrinology | 2004

Biology of primate relaxin: A paracrine signal in early pregnancy?

Eric Hayes

Relaxin is a peptide hormone that exerts numerous effects in a variety of tissues across a broad range of species. Although first identified more than 75 years ago interest in relaxin biology has waxed and waned over the years consistent with peaks and troughs of new experimental data on its wide-ranging biological effects and advances in relaxin enabling technologies. Recent insights into species-dependent differences in relaxin biology during pregnancy have once again stimulated a relative surge of interest in the study of relaxins reproductive biology. Identification and pharmacological characterization of orphaned relaxin receptors and exploration of its paracrine effects on pregnancy using genomic and proteomic technologies have succeeded in fueling current interest in relaxin research. Primates and non-primate vertebrates exhibit very disparate profiles of relaxin genomics, proteomics and functional biology. Non-human primates appear to exhibit a very close similarity to humans with respect to relaxin reproductive biology but the similarities and subtle differences are only just beginning to be understood. We, and others, have shown that relaxin produces significant changes to the non-human primate endometrium during the peri-implantation period that are consistent with relaxins long perceived role as a paracrine modulator of pregnancy. The purpose of this review is to summarize the reproductive biology of relaxin in non-human primates with a specific emphasis on the paracrine role of ovarian and endometrial relaxin during embryo implantation and early pregnancy.


Human Reproduction | 2010

In vitro developmental potential of macaque oocytes, derived from unstimulated ovaries, following maturation in the presence of glutathione ethyl ester

Eliza Curnow; J. P. Ryan; Douglas M. Saunders; Eric Hayes

BACKGROUND The inadequacies of oocyte in vitro maturation (IVM) systems for both non-human primates and humans are evidenced by reduced fertilization and poor embryonic development, and may be partly explained by significantly lower glutathione (GSH) contents compared with in vivo matured (IVO) oocytes. As this influence has not been fully explored, this study investigated the effect of the GSH donor, glutathione ethyl ester (GSH-OEt), on the IVM and development of macaque oocytes as a model of human oocyte IVM. METHODS Macaque oocytes derived from unstimulated ovaries were cultured in mCMRL-1066 alone or supplemented with 3 or 5 mM GSH-OEt. In vitro matured oocytes were subjected to the GSH assay, fixed for the assessment of spindle morphology or prepared ICSI. Embryo development of zygotes cultured in mHECM-9 was assessed up to Day 9 post-ICSI. RESULTS Supplementation of the maturation medium with GSH-OEt significantly increased oocyte maturation and normal fertilization rates compared with control oocytes, but only 5 mM GSH-OEt significantly increased the oocyte and cumulus cell GSH content. Confocal microscopy revealed significant differences in the spindle morphology between IVO and control in vitro matured metaphase II oocytes. Oocytes matured with 5 mM GSH-OEt exhibited spindle area and spindle pole width similar to that seen in the IVO oocyte. While no significant differences were observed in blastocyst rates, addition of 3 mM GSH-OEt during IVM significantly increased the proportion of embryos developing to the 5-8 cell stage while 5 mM GSH-OEt significantly increased the proportion of morula-stage embryos compared with controls. CONCLUSIONS Supplementation of the IVM medium with GSH-OEt promotes better maturation and normal fertilization of macaque oocytes compared with non-supplemented medium. However, further improvement of the primate oocyte IVM culture system is required to support better blastocyst development of oocytes derived from unstimulated ovaries.


Reproduction, Fertility and Development | 2010

Developmental potential of bovine oocytes following IVM in the presence of glutathione ethyl ester.

Eliza Curnow; J. P. Ryan; Douglas M. Saunders; Eric Hayes

Glutathione (GSH) is synthesised during oocyte maturation and represents the oocytes main non-enzymatic defence against oxidative stress. Inadequate defence against oxidative stress may be related to poor embryo quality and viability. In the present study, bovine oocytes were matured in vitro in the presence of GSH ethyl ester (GSH-OEt), a cell permeable GSH donor, and its effects on subsequent fertilisation and embryo development were assessed. GSH-OEt significantly increased the GSH content of IVM oocytes without affecting fertilisation or Day 3 cleavage rates. Maturation in the presence of GSH-OEt did not significantly increase the blastocyst rate compared with control oocytes. However, 5 mM GSH-OEt treatment resulted in significantly higher blastocyst total cell number. The GSH level of IVM oocytes was significantly decreased in the absence of cumulus cells and when cumulus-oocyte complexes were cultured in the presence of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. The addition of GSH-OEt to cumulus-denuded or BSO-treated oocytes increased the GSH content of bovine oocytes and restored the rate of normal fertilisation, but not embryo development, to levels seen in control oocytes. Thus, GSH-OEt represents a novel approach for effective in vitro elevation of bovine oocyte GSH and improvement in blastocyst cell number.


Reproduction, Fertility and Development | 2008

Bovine in vitro oocyte maturation as a model for manipulation of the γ-glutamyl cycle and intraoocyte glutathione

Eliza Curnow; John Ryan; Douglas M. Saunders; Eric Hayes

Glutathione (GSH) is the main non-enzymatic defence against oxidative stress and is a critical intracellular component required for oocyte maturation. In the present study, several modulators of intracellular GSH were assessed for their effect on the in vitro maturation (IVM) and intracellular GSH content of bovine metaphase (MII) oocytes. Of the five GSH modulators tested, only the cell-permeable GSH donor glutathione ethyl ester (GSH-OEt) significantly increased the GSH content of IVM MII oocytes in a concentration-dependent manner without adversely affecting oocyte maturation rate. The GSH level in IVM MII oocytes was greatly influenced by the presence or absence of cumulus cells and severely restricted when oocytes were cultured in the presence of buthionine sulfoximine (BSO), an inhibitor of GSH synthesis. The addition of GSH-OEt to cumulus-denuded or BSO-treated oocytes increased the GSH content of bovine MII oocytes. Supplementation of the maturation medium with bovine serum albumin (BSA) or fetal calf serum (FCS) affected the GSH content of IVM MII oocytes, with greater levels attained under BSA culture conditions. The addition of GSH-OEt to the maturation medium increased the GSH content of IVM MII oocytes, irrespective of protein source. Spindle morphology, as assessed by immunocytochemistry and confocal microscopy, displayed distinct alterations in response to changes in oocyte GSH levels. GSH depletion caused by BSO treatment tended to widen spindle poles and significantly increased spindle area. Supplementation of the IVM medium with GSH-OEt increased spindle length, but did not significantly alter spindle area or spindle morphology. GSH-OEt represents a novel oocyte-permeable and cumulus cell-independent approach for effective elevation of mammalian oocyte GSH levels.


Reproduction, Fertility and Development | 2010

Oocyte glutathione and fertilisation outcome of Macaca nemestrina and Macaca fascicularis in in vivo- and in vitro-matured oocytes

Eliza Curnow; J. P. Ryan; Douglas M. Saunders; Eric Hayes

Fertilisation and development of IVM non-human primate oocytes is limited compared with that of in vivo-matured (IVO) oocytes. The present study describes the IVM of macaque oocytes with reference to oocyte glutathione (GSH). Timing of maturation, comparison of IVM media and cysteamine (CYS) supplementation as a modulator of GSH were investigated. A significantly greater proportion of oocytes reached MII after 30 h compared with 24 h of IVM. Following insemination, IVM oocytes had a significantly lower incidence of normal fertilisation (i.e. 2PN = two pronuclei and at least one polar body) and a higher rate of abnormal fertilisation (1PN = one pronucleus and at least one polar body) compared with IVO oocytes. Immunofluorescence of 1PN zygotes identified incomplete sperm head decondensation and failure of male pronucleus formation as the principal cause of abnormal fertilisation in IVM oocytes. The IVO oocytes had significantly higher GSH content than IVM oocytes. Cumulus-denuded oocytes had significantly lower GSH following IVM compared with immature oocytes at collection. Cysteamine supplementation of the IVM medium significantly increased the GSH level of cumulus-intact oocytes and reduced the incidence of 1PN formation, but did not improve GSH levels of the denuded oocyte. Suboptimal GSH levels in macaque IVM oocytes may be related to reduced fertilisation outcomes.


Fertility and Sterility | 2011

Primate model of metaphase I oocyte in vitro maturation and the effects of a novel glutathione donor on maturation, fertilization, and blastocyst development

Eliza Curnow; John P. Ryan; Douglas M. Saunders; Eric Hayes

OBJECTIVE To assess the effect of glutathione ethyl ester (GSH-OEt) on the development of macaque metaphase (MI) oocytes as a model for human MI oocyte in vitro maturation (IVM). DESIGN Prospective cohort study. SETTING Nonhuman primate assisted reproductive technology program. ANIMAL(S) Twenty-three Macaca fascicularis females aged 6.5-12.5 years. INTERVENTION(S) Ovarian stimulation and maturation of MI oocytes in [1] human tubal fluid (HTF), [2] mCMRL-1066, [3] mCMRL-1066+GSH-OEt 3 mM, or [4] mCMRL-1066+GSH-OEt 5 mM. Oocytes were assessed for maturation after 4-6 hours (early) and 18-20 hours (late) of culture. Mature oocytes were inseminated or subjected to glutathione (GSH) assay. Zygotes were cultured to the blastocyst stage for total differential cell counts. MAIN OUTCOME MEASURE(S) Oocyte maturation rate, GSH content, pronuclear formation and blastocyst development, and cell number were compared between IVM treatment groups and sibling in vivo matured (IVO) MII oocytes. RESULT(S) Compared with HTF, mCMRL-1066 supported higher rates of normal fertilization and blastocyst development in early but not late maturing MI-MII oocytes. Five micromoles of GSH-OEt significantly increased blastocyst total cell and inner cell mass cell number in early MI-MII oocytes compared with IVO and IVM controls. GSH-OEt significantly increased oocyte GSH content and fertilization in late maturing oocytes but not blastocyst development. CONCLUSION(S) GSH-OEt positively affects the development of early and late maturing IVM oocytes.


Primate Models of Children's Health and Developmental Disabilities | 2008

Future Directions: Assisted Reproductive Technologies as Tools for Creating Nonhuman Primate Models of Developmental Disability

Eric Hayes; Eliza Curnow; Jennifer C. Potter

Publisher Summary Biological model systems that support descriptive pathology based on gene–environment interactions and span the spectrum from pathogenesis to clinical phenotype are required for basic scientific and clinically meaningful study of developmental disabilities. Developmental disorders encompass a broad range of genetic abnormalities that are subject to epigenetic and environmental modification. Simple nonmammalian organism and rodent model systems have proven extremely useful for the study of gene function related to developmental disability. However, for some developmental disorders, nonprimate orthologs of the affected human gene(s) may not exist. Furthermore, sensory modalities and functionally integrated physiological systems that respond to and are affected by epigenetic and environmental influences are known to be quite different in primate than in nonprimate species. Given these differences, nonprimate models of developmental disabilities may exhibit vastly different phenotypes compared with the human condition. Assisted reproductive technologies (ARTs) encompass an enormous array of skills from both basic sciences and clinical medicine, span the spectrum of most species used for scientific experimentation, and cover molecular to integrated systems approaches to reproductive biology. Advances in embryology and stem cell-based. ARTs are directly responsible for the generation of genetically modified and genetically identical mammals and have had a large impact on progress in rodent models of developmental disability. Thus development and application of ARTs in nonhuman primates represents a promising avenue for expanded use of nonhuman primate models of developmental disabilities.


Hayati Journal of Biosciences | 2006

Diurnal Patterns of Testosterone and Cortisol Metabolites in Fecal of Javan Gibbons (Hylobates moloch) in Captivity

Pudji Astuti; Tuty Laswardi Yusuf; Eric Hayes; Hera Maheshwari; Luthfiralda Sjahfirdi; Dondin Sajuthi

The term of allelopathy refers to chemical interactions (inhibitory or stimulatory) between plants, between plants and microorganisms, and between microorganisms. The wealth of information on the processes, procedures, and practices of allelopathy has contributed to understanding this field of science. Recently, researches of allelopathy have been conducted in laboratory, greenhouse, and field with multifaceted standpoint in some concerning area: (i) allelochemicals identifications and screening test; (ii) ecological and physiological aspects of allelopathy; (iii) genetic studies and the possibilities of using plant breeding or genetic manipulation to enhance allelopathic varieties; (iv) the use of allelopathic potential in the biological control, including as natural pesticide, of weeds and plant diseases as eco-friendly approach for sustainable agriculture scheme. Key words: Allelochemicals, biological control, sustainable agriculture


Hayati Journal of Biosciences | 2006

Pola Diurnal Metabolit Testosteron dan Kortisol di dalam Feses Owa Jawa (Hylobates moloch) di Penangkaran

Pudji Astuti; Tuty Laswardi Yusuf; Eric Hayes; Hera Maheshwari; Luthfiralda Sjahfirdi; Dondin Sajuthi

The aims of this research were to determine diurnal patterns of testosterone and cortisol metabolites to predict the testis functional status. In this study, fecal testosterone and cortisol were quantified in 77 samples from three male Hylobates moloch during a course of three months period. These data showed that the highest concentration of fecal testosterone occured at 18.00-06.00 (23.61 ng/g dried feces), then declined gradually. The lowest concentration was in the evening (5.54 ng/g dried feces). Our tests showed that there was a decrease in the mean testosterone concentration from 06.00-10.00 to 10.00-14.00 to 14.00-18.00. For cortisol, the highest concentration occured at 06.00-10.00 (597.84 ng/g dried feces), then decline gradually in the evening (225.73 ng/g dried feces).

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Eliza Curnow

University of Washington

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Dondin Sajuthi

Bogor Agricultural University

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Hera Maheshwari

Bogor Agricultural University

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Tuty Laswardi Yusuf

Bogor Agricultural University

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G. Chow

University of Washington

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