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PS-1.2 Sperm differentiation from stem cells
Abstracts - Aspire: ART Paving the way for new frontiers
factors including retinoic acid (RA), PGC enter meiosis as identified by chromosomal alignment and expression of meiotic genes. Although female PGC are more advanced in their invitro differentiation, meiosis is not successfully completed in both male and female PGC. It appears that full developmental potential of the female gamete from in-vivo- and in-vitroderived GS cells requires stimulation by factors controlling meiosis and follicular growth. The development of earlier stage in-vivo-derived PGC (E12.5) into primary and secondary oocytes requires the support of the complete cell population of the genital ridge followed by addition of growth factors (Obata et al., 2002). The presentation will include an overview on oocyte differentiation from stem cells and similarities and differences between in-vivo and in-vitro oocyte development, which may be the key to successful oogenesis in the culture dish PS-1.2 Sperm differentiation from stem cells Nayernia K NESCI and Institute of Human Genetics, University of Newcastle-upon-Tyne Stem cells offer substantial opportunities for providing welldefined differentiated cells for drug discovery, toxicology, and regenerative medicine, but the development of efficient techniques for controlling and directing their differentiation, present a substantial challenge. We developed a new promoter based genetic selection of germline stem cells (GSC). Germline stem cells, which can self-renew and generate gametes, are unique stem cells in that they are solely dedicated to transmit genetic information from generation to generation. Extensive studies on these two stem cell types in different organisms over the past few years have revealed some commonalities in the mechanisms controlling their self-renewal and differentiation. Furthermore, germline or somatic cells in various organisms and sexes also exhibit their own unique ways of regulating stem cell function. Mouse embryonic stem (ES) cells derive from the inner cell mass of the blastocyst and give rise to the three primitive embryonic layers, which later will form all the different tissue types of an adult. Embryonic stem cells are thus defined as totipotent cells. In vitro, these cells can give rise to all the somatic cells. We developed a strategy for the establishment of germline stem cell lines from embryonic stem cells. These cells are able to undergo meiosis, generate haploid male gametes in vitro and are functional, as shown by fertilization after intracytoplasmic injection into mouse oocytes. Molecular and cellular mechanisms underlying differentiation of ES to functional gametes should be elucidated in future research. In other approach, we show that bone marrow stem (BMS) cells are able to trans-differentiate into male germ cells. BMS cellderived germ cells expressed the known molecular markers of primordial germ cells. The ability to derive male germ cells from ES and BMS cells reveals novel aspects of germ cell development and opens the possibilities for use of these cells in reproductive medicine.
S-4 Reproductive BioMedicine Online, Vol. 16, Suppl. 2, April 2008
PS-1.3 Guided differentiation of human embryonic stem cells Chung H-M CHA Stem Cell Institute, Pochon CHA University College of Medicine Human embryonic stem cells (hESC) are established from the inner cell mass of preimplantation blastocysts. These cells exhibit unlimited proliferation and pluripotency, the ability to differentiate into all types of tissues, and are promising resources for regenerative medicine, which requires large numbers of a particular cell type. hESC are therefore unlimited sources for cell-based therapies if they can be successfully guided toward specific lineages with high populations. During hESC differentiation, embryoid bodies (EB), tissue-like spheroids of aggregated cells, are spontaneously formed from hESC in invitro suspension culture. Therefore, many studies have used EB to differentiate effectively hESC toward target lineages with high populations by altering their biological environments. Though several techniques have been developed, it remains challenging to efficiently differentiate hESC only toward specific lineages and to expand them to numbers required for cell therapy. Thus, differentiation and expansion have to be considered as primary goals prior to clinical applications of hESC. We focused on the development of functional endothelial or endothelial progenitor cells and their differentiation from human ES cells for therapeutic application. During the early stages of EB development, vasculogenesis takes place and blood vessels form through a multi-step process in which endothelial cell precursors differentiate, expand, and coalesce to form a network of primitive tubules. Endothelial cells play various important roles in blood vessels, including control of blood pressure, blood clotting, angiogenesis, and inflammation. Recently, many studies have reported that endothelial cell therapy is effective in regenerating damaged vessels and in curing vascular disease. Developing techniques of endothelial cell isolation and growth with high yield and purity will therefore facilitate therapies to cure various vascular diseases. In this presentation, the author will describe the development of an efficient method to obtain highly purified endothelial cells (EC) and vascular angiogenic progenitor cells (VAPC) from HESC and discuss whether HESC-EC or VAPC has therapeutic potential for the treatment of ischemia in hindlimb ischemic animal models. This work was supported by a grant (SC2190) from the Stem Cell Research Centre of the 21C Frontier R and D Program funded by the Ministry of Science and Technology, Republic of Korea. PS-1.4 Tracking stem cells in vivo Radda G Singapore Bioimaging Consortium, Head of the Department of Physiology, Anatomy and Genetics, University of Oxford The Singapore Bioimaging Consortium (SBIC) was set up in the first instance to develop facilities and research programmes for in-vivo imaging of model organisms for human disease and for coordinating, at the national level, bioimaging research in Singapore. Its main biomedical targets are cancer, metabolic medicine and regenerative medicine. Research into stem cell biology is well advanced
factors including retinoic acid (RA), PGC enter meiosis as identified by chromosomal alignment and expression of meiotic genes. Although female PGC are more advanced in their invitro differentiation, meiosis is not successfully completed in both male and female PGC. It appears that full developmental potential of the female gamete from in-vivo- and in-vitroderived GS cells requires stimulation by factors controlling meiosis and follicular growth. The development of earlier stage in-vivo-derived PGC (E12.5) into primary and secondary oocytes requires the support of the complete cell population of the genital ridge followed by addition of growth factors (Obata et al., 2002). The presentation will include an overview on oocyte differentiation from stem cells and similarities and differences between in-vivo and in-vitro oocyte development, which may be the key to successful oogenesis in the culture dish PS-1.2 Sperm differentiation from stem cells Nayernia K NESCI and Institute of Human Genetics, University of Newcastle-upon-Tyne Stem cells offer substantial opportunities for providing welldefined differentiated cells for drug discovery, toxicology, and regenerative medicine, but the development of efficient techniques for controlling and directing their differentiation, present a substantial challenge. We developed a new promoter based genetic selection of germline stem cells (GSC). Germline stem cells, which can self-renew and generate gametes, are unique stem cells in that they are solely dedicated to transmit genetic information from generation to generation. Extensive studies on these two stem cell types in different organisms over the past few years have revealed some commonalities in the mechanisms controlling their self-renewal and differentiation. Furthermore, germline or somatic cells in various organisms and sexes also exhibit their own unique ways of regulating stem cell function. Mouse embryonic stem (ES) cells derive from the inner cell mass of the blastocyst and give rise to the three primitive embryonic layers, which later will form all the different tissue types of an adult. Embryonic stem cells are thus defined as totipotent cells. In vitro, these cells can give rise to all the somatic cells. We developed a strategy for the establishment of germline stem cell lines from embryonic stem cells. These cells are able to undergo meiosis, generate haploid male gametes in vitro and are functional, as shown by fertilization after intracytoplasmic injection into mouse oocytes. Molecular and cellular mechanisms underlying differentiation of ES to functional gametes should be elucidated in future research. In other approach, we show that bone marrow stem (BMS) cells are able to trans-differentiate into male germ cells. BMS cellderived germ cells expressed the known molecular markers of primordial germ cells. The ability to derive male germ cells from ES and BMS cells reveals novel aspects of germ cell development and opens the possibilities for use of these cells in reproductive medicine.
S-4 Reproductive BioMedicine Online, Vol. 16, Suppl. 2, April 2008
PS-1.3 Guided differentiation of human embryonic stem cells Chung H-M CHA Stem Cell Institute, Pochon CHA University College of Medicine Human embryonic stem cells (hESC) are established from the inner cell mass of preimplantation blastocysts. These cells exhibit unlimited proliferation and pluripotency, the ability to differentiate into all types of tissues, and are promising resources for regenerative medicine, which requires large numbers of a particular cell type. hESC are therefore unlimited sources for cell-based therapies if they can be successfully guided toward specific lineages with high populations. During hESC differentiation, embryoid bodies (EB), tissue-like spheroids of aggregated cells, are spontaneously formed from hESC in invitro suspension culture. Therefore, many studies have used EB to differentiate effectively hESC toward target lineages with high populations by altering their biological environments. Though several techniques have been developed, it remains challenging to efficiently differentiate hESC only toward specific lineages and to expand them to numbers required for cell therapy. Thus, differentiation and expansion have to be considered as primary goals prior to clinical applications of hESC. We focused on the development of functional endothelial or endothelial progenitor cells and their differentiation from human ES cells for therapeutic application. During the early stages of EB development, vasculogenesis takes place and blood vessels form through a multi-step process in which endothelial cell precursors differentiate, expand, and coalesce to form a network of primitive tubules. Endothelial cells play various important roles in blood vessels, including control of blood pressure, blood clotting, angiogenesis, and inflammation. Recently, many studies have reported that endothelial cell therapy is effective in regenerating damaged vessels and in curing vascular disease. Developing techniques of endothelial cell isolation and growth with high yield and purity will therefore facilitate therapies to cure various vascular diseases. In this presentation, the author will describe the development of an efficient method to obtain highly purified endothelial cells (EC) and vascular angiogenic progenitor cells (VAPC) from HESC and discuss whether HESC-EC or VAPC has therapeutic potential for the treatment of ischemia in hindlimb ischemic animal models. This work was supported by a grant (SC2190) from the Stem Cell Research Centre of the 21C Frontier R and D Program funded by the Ministry of Science and Technology, Republic of Korea. PS-1.4 Tracking stem cells in vivo Radda G Singapore Bioimaging Consortium, Head of the Department of Physiology, Anatomy and Genetics, University of Oxford The Singapore Bioimaging Consortium (SBIC) was set up in the first instance to develop facilities and research programmes for in-vivo imaging of model organisms for human disease and for coordinating, at the national level, bioimaging research in Singapore. Its main biomedical targets are cancer, metabolic medicine and regenerative medicine. Research into stem cell biology is well advanced