• 한국발생생물학회지:발생과생식
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• 제15권1호
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• pp.25-30
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• 2011

Embryonic stem (ES) cells can self-renew maintaining the undifferentiated state. Self renewal requires many factors such as Oct4, Sox2, FoxD3, and Nanog. NF-${\kappa}B$ is a transcription factor involved in many biological activities. Expression and activity of NF-${\kappa}B$ increase upon differentiation of ES cells. Reportedly, Nanog protein directly binds to NF-${\kappa}B$ protein and inhibits its activity in ES cells. Here, we found a potential binding site of NF-${\kappa}B$ in the human Nanog promoter and postulated that NF-${\kappa}B$ protein may regulate expression of the Nanog gene. We used human embryonic carcinoma (EC) cells as a model system of ES cells and confirmed decrease of Nanog and increase of NF-${\kappa}B$ upon differentiation induced by retinoic acid. Although deletion analysis on the DNA fragment including NF-${\kappa}B$ binding site suggested involvement of NF-${\kappa}B$ in the negative regulation of the promoter, site-directed mutation of NF-${\kappa}B$ binding site had no effect on the Nanog promoter activity. Furthermore, no direct association of NF-${\kappa}B$ with the Nanog promoter was detected during differentiation. Therefore, we conclude that NF-${\kappa}B$ protein may not be involved in transcriptional regulation of Nanog gene expression in EC cells and possibly in ES cells.

• Reproductive and Developmental Biology
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• 제35권1호
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• pp.123-129
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• 2011

The pig has been considered to serve as an appropriate model of human disease. Therefore, establishment of porcine embryonic stem cell lines is important. The purpose of the present study was to further work in this direction. We produced porcine parthenogenetic embryos, and separately aggregated two of each of two-cell ($2{\times}2$), four-cell ($2{\times}4$), and eight-cell ($2{\times}8$) embryos derived by parthenogenesis. After culture for 4 days, the developmental ability of the aggregates and total blastocyst cell numbers were evaluated. The percentage of blastocysts was significantly higher in both $2{\times}4$- and $2{\times}8$-aggregated embryos ($58.3{\pm}1.9%$ and $37.2{\pm}2.8%$, respectively) than in the control or $2{\times}2$-aggregated embryos ($23.6{\pm}1.1%$ and $12.5{\pm}2.4%$, respectively). Total blastocyst cell numbers were increased in the $2{\times}4$- and $2{\times}8$-aggregated embryos (by $44{\pm}3.0%$ and $45{\pm}3.3%$, respectively) compared with those of control or $2{\times}2$-aggregated embryos ($30.5{\pm}2.1%$ and $30.7{\pm}2.6%$, respectively; p<0.05). The levels of mRNA encoding Oct-4 were higher in both the $2{\times}4$- and $2{\times}8$-aggregated embryos than in the control. When blastocysts derived from $2{\times}4$- aggregated embryos or intact normal embryos were cultured on mouse embryonic fibroblast feeder cells to obtain porcine stem cells, blastocysts from aggregated embryos formed colonies that were better in shape compared with those derived from intact blastocysts. Together, the data show that aggregation of porcine embryos not only improves blastocyst quality but also serves as an efficient procedure by which porcine embryonic stem cells can become established.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2004년도 제47차 추계학술대회
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• pp.68-69
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• 2004

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2003년도 제3회 발생공학 국제심포지움 및 학술대회
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• pp.97-97
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• 2003

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2001년도 제41차 추계학술대회
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• pp.103-103
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• 2001

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2002년도 제42차 춘계학술대회
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• pp.89.1-89.1
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• 2002

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2002년도 제42차 춘계학술대회
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• pp.88-89
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• 2002

• Clinical and Experimental Reproductive Medicine
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• 제36권3호
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• pp.143-150
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• 2009

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.103-103
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• 2003

The purpose of this study is to evaluate an efficacy of in vitro differentiated human embryonic stem (hES, MB03) cells expressing Nurr1 in relief of symptomatic motor behavior of Parkinson's disease (PD) animal models MB03 was genetically modified to express Nurr1 protein and was induced to differentiate according to 2-/4+ protocol using retinoic acid and ascorbic acid. The differentiation-induced cells were selected for 10 to 20 days thereafter in N2 medium. Upon selection, cells expressing GFAP, TH, or NF200 were 38.8%, 11%, and 20.5%, respectively. in order to examine therapeutic effects of the differentiated cells in PD animal model, rats were unilaterally lesioned by administration of 6-kydroxydopamine HCI (6-OHDA) into medial forebrain region (MFB, AP -4.4 mm, ML 1.2 mm, DV 78 mm with incision bar set at -2.4 mm), as a reference to bregma and the surface of the skull. Confirmation of successful lesion by apomorphine-induced rotational behavior, differentiated cells were transplanted into the striatum (AP 1.0, ML 3.5, DV -5.0; AP 0.6, ML 2.5, DV -4.5). Improvements of asymmetric motor behavior by the transplantation were examined every two weeks after the surgery. In two weeks, numbers of rotation by the experimental rats were $-14.8 \pm 33.9%$ (P<0.05) of the number before transplantation, however, the ratio increased slightly to $13.6 \pm 56.3%$ in six weeks. In contrast, the ratio of sham-grafted animals ranged from 112.3+8.5% to 139.2+28.9% during the examination. Immunohistochemical studies further confirmed the presence, survival, migration, and expression of TH of the transplanted human cells.

• Clinical and Experimental Reproductive Medicine
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• 제29권2호
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• pp.117-127
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• 2002

Objective: This study was to investigate the generation of the functional neuron derived from human embryonic stem (hES, MB03) cells on in vitro neural cell differentiation system. Methods: For neural progenitor cell formation derived from hES cells, we produced embryoid bodies (EB: for 5 days, without mitogen) from hES cells and then neurospheres (for $7{\sim}10$ days, 20 ng/ml of bFGF added N2 medium) from EB. And then finally for the differentiation into mature neuron, neural progenitor cells were cultured in i) N2 medium only (without bFGF), ii) N2 supplemented with 20 ng/ml platelet derived growth factor-bb (PDGF-bb) or iii) N2 supplemented with 5 ng/ml brain derived neurotrophic factor (BDNF) for 2 weeks. Identification of neural cell differentiation was carried out by immunocytochemistry using $\beta_{III}$-tubulin (1:250), MAP-2 (1:100) and GFAP (1:500). Also, generation of functional neuron was identified using anti-glutamate (Sigma, 1:1000), anti-GABA (Sigma, 1:1000), anti-serotonin (Sigma, 1:1000) and anti-tyrosine hydroxylase (Sigma, 1:1000). Results: In vitro neural cell differentiation, neurotrophic factors (PDGF and BDNF) treated cell groups were high expressed MAP-2 and GFAP than non-treated cell group. The highest expression pattern of MAP-2 and $\beta_{III}$-tubulin was indicated in BDNF treated group. Also, in the presence of PDGF-bb or BDNF, most of the neural cells derived from hES cells were differentiated into glutamate and GABA neuron in vitro. Furthermore, we confirmed that there were a few serotonin and tyrosine hydroxylase positive neuron in the same culture environment. Conclusion: This results suggested that the generation of functional neuron derived from hES cells was increased by addition of neurotrophic factors such as PDGF-bb or BDNF in b-FGF induced neural cell differentiation system and especially glutamate and GABA neurons were mainly produced in the system.