• 한국발생생물학회지:발생과생식
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• 제6권1호
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• pp.55-66
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• 2002

배아줄기세포(embryonic stem cell, ESC)는 미분화상태로 지속적인 계대가 가능하며, 정상 핵형과 전 분화능(pluripotency)을 가져 생체내-외에서 분화 유도시 삼배엽성의 모든 세포로 분화 가능하다. ESC를 feeder 세포 없이 부유배양하면 배아체(embryoid body, EB)를 형성하고, 초기 배아 발생과 유사한 분화 양상을 갖는다. ESC의 분화 유도가 초기배아 발생처럼 생식호르몬(GTH: FSH, LH; steroids)의 영향을 받는지는 불명하다. 본 연구는 ESC가 분화과정중 생식호르몬처리에 의해 그들 수용체가 발현되는가를 알아보고자 하였다. 순계혈통 생쥐인 C57BL/6J에서 과배란 유도후 포배를 수획하고, 유사분열적으로 불활성화된 feeder 세포와 공배양하여, 계대배양 하는 중 배아줄기세포주(JHYl)를 확립하였다. JHY1의 alkaline phosphatase 활성과 SSEA-1, 3, 4 발현을 통해 ESC임을 확인하였다. Feeder 세포 없이 ESC를 계대배양 후 호르몬처리(FSH LH E$_2$, P$_4$, T)하에서 5일 동안 부유배양하여 배아체를 형성시키고, 이후 7일 동안 부착배양하여 분화를 유도하였다. GTH와 스테로이드의 수용체 발현 실험에서 ESC에 E$_2$ 처리에 의한 LHR의 발현 증가를 제외한 나머지 호르몬 처리군에서 ESC보다 낮은 생식호르몬의 수용체 발현이 관찰되었다. 생식호르몬을 농도별 수용체 발현 정도는 증감되지 않았다. 미분화 ESC 표지유전자인 Oct-4는 호르몬 처리군에서도 발현되었다. 각 배엽의 표지유전자들(영양세포, handl; 외배엽성, keratin와fgf-5; 중배엽성, enolase와 $\alpha$ -globin; 내배엽성, gata-4와 $\alpha$ -fetoprotein) 등의 발현 양상을 조사한 결과 호르몬 처리후 내배엽성 표지유전자외에는 발현 증가가 관찰되지 않았다. 즉 생식호르몬에 의해 gata-4, $\alpha$-fetoprotein의 발현이 증가되는 것으로 보아 내배엽성 계열로의 분화 유도가 이루어진 것으로 사료된다.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제53차 추계학술대회 초록집
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• pp.116-117
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• 2007

• 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.88-89
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• 2002

• Fisheries and Aquatic Sciences
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• 제19권4호
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• pp.16.1-16.8
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• 2016

To culture germline stem cells in vitro, establishment of the cell lines that can be used as the feeder cells is a prerequisite. In this study, we tried to establish gonad-derived cell lines in Siberian sturgeon (Acipenser baerii). Five 1-year-old A. baerii were used as a donor of gonad tissues, and gonad-dissociated cells were cultured in vitro. Subsequently, determination of growth conditions, long-term culture, characterization, and cryopreservation of the cell lines were also conducted. Five gonad-derived cell lines were stably established and cultured continuously over at least the 73th passage and 402 culture days under the media containing 20 % fetal bovine serum at $28^{\circ}C$. All cell lines consisted of two main cell types based on morphology even if the ratio of the two cell types was different depending on cell lines. Despite long-term culture, all cell lines maintained diploid DNA contents and expression of several genes that are known to express in the A. baerii gonad. After freezing and thawing of the cell lines, post-thaw cell viabilities between 57.6 and 92.9 % depending on cell lines were indentified, suggesting that stable cryopreservation is possible. The results and the cell lines established in this study will contribute to the development of an in vitro system for A. baerii germline stem cell culture.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.902-904
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• 1993

This paper contains the terminal developement for the feeder remote unit in Korea Distribution Automation System. This terminal unit has serval functions in order to do feeder auotmation as following, the open/close controls and gathering status informations of switchgears, getting line currents and voltages, distribution fault. So FRU has four modules to do those functions-Logic Controller, Relay Controller, Data Acquisition, Display, Power Supply etc. The FRU should be on allays, so AC power is supplied before & behind the switchgear. Power Supply is made up with AC/DC, DC/DC, Battery and/or SOLAR CELLS & CONTROLLER. It is important for the supply to protect against some Surges, because surges are happened so many times. Surge test is fellowing the standard IEC 801-5 or IEEE 587.

• International Journal of Molecular Medicine
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• 제43권5호
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• pp.2230-2240
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• 2019

Hair follicles (HFs) are a well-characterized niche for adult stem cells (SCs), and include epithelial and melanocytic SCs. HF cells are an accessible source of multipotent adult SCs for the generation of the interfollicular epidermis, HF structures and sebaceous glands in addition to the reconstitution of novel HFs in vivo. In the present study, it was demonstrated that HF cells are able to be induced to differentiate into cardiomyocyte-like cells in vitro under specific conditions. It was determined that HF cells cultured on OP9 feeder cells in KnockOut-Dulbecco's modified Eagle's medium/B27 in the presence of vascular endothelial growth factors differentiated into cardiomyocyte-like cells that express markers specific to cardiac lineage, but do not express non-cardiac lineage markers including neural stem/progenitor cell, HF bulge cells or undifferentiated spermatogonia markers. These cardiomyocyte-like cells exhibited a spindle- and filament-shaped morphology similar to that presented by cardiac muscles and exhibited spontaneous beating that persisted for over 3 months. These results demonstrate that SC reprogramming and differentiation may be induced without resulting in any genetic modification, which is important for the clinical applications of SCs including tissue and organ regeneration.

• Animal Bioscience
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• 제36권3호
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• pp.429-440
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• 2023

Objective: 12-oxo-5Z,8Z,10E,14Z-eicosatetraenoic acid (12-KETE), a metabolite of arachidonic acid, is a strong candidate signal for placenta separation following calf discharge at delivery. In the present study, the effects of 12-KETE on bovine trophoblast cells were investigated to determine its function in the placentome at delivery. Methods: Bovine trophoblast cells derived from blastocysts were used. They were cocultured with or without fibroblasts derived from bovine placentome and/or bovine uterine epithelial cells. 12-KETE was added to the culture medium. Results: Bovine trophoblast cells contained binucleate cells and strongly expressed caudal type homeobox 2 (CDX-2) genes. Addition of 12-KETE to the trophoblast cell colony without feeder cells or that on a fibroblast monolayer induced rapid exfoliation of the colony. After 12-KETE addition, trophoblast cells emitted strong fluorescence caused by the degradation of dye-quenched collagen, indicating that 12-KETE activated matrix metalloproteinase of the trophoblast cells. Exfoliated cell colonies were stained with YOPRO-1, but not propidium iodide (PI). Moreover, DNA fragmentation and Bcl-2 associated X protein (Bax) gene (apoptosis stimulator) upregulation were observed in exfoliated cells, indicating that 12- KETE induced trophoblast cell apoptosis. These results were consistent with previous in vivo observations; however, even a lower concentration of 12-KETE activated trophoblast protease. Meanwhile, fibroblasts derived from the bovine placentome converted arachidonic acid to 12-KETE. Conclusion: These observations indicate that 12-KETE may serve as a signal for placenta separation at delivery.

• Asian-Australasian Journal of Animal Sciences
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• 제9권5호
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• pp.583-590
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• 1996

The purpose of this study was to evaluate some factors in the bovine embryonic development from one-cell to blastocyst using modified synthetic oviduct fluid medium (mSOFM), after maturation and in vitro fertilization of the oocytes. The embryonic development to the blastocyst stage was assessed at 7-10 days after in vitro fertilization, and the total cells in the blastocysts were counted by staining nuclei with fluorochrome. Some commercial calf sera (CS) and a superovulated cow serum had different effects on the embryonic development to the blastocyst stage (8.6-21.4%), dependent upon their product lots, although the development might not be affected at least by serum progesterone levels. ${\beta}$-Mercaptoethanol (${\beta}$-ME) supplemented into mSOFM was effective to the embryonic development (27.8%), as well as the co-culture system with cumulus cells (19.5%). In a serum- and feeder cell-free culture using mSOFM containing several growth factors and ${\beta}$-ME instead of CS plus co-cultured cumulus cells, bovine serum albumin (BSA, fraction V), but not polyvinyl alcohol (PVA), was highly effective in embryonic development to the blastocyst stage, almost comparable to CS in the serum-contained culture (CS, BSA and PVA; 27.8, 19.5 and 5.7%, respectively). However, fatty acid free BSA rather reduced the number of developed blastocysts, compared with fraction V BSA (7.3 vs 29.4%). In the serum- and feeder cell-free culture, supplement of glucose to the medium (final 2.0 mM) stimulated the cell proliferation of developing embryos 120 hr after in vitro fertilization. These results indicated that a serum-free medium supplemented with ${\beta}$-ME could successfully support the development of bovine one-cell embryos to the blastocyst stage. Moreover, supplement of glucose and fatty acids to the medium might support preferably the development and cell proliferation of embryos.

• 한국가축번식학회지
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• 제18권4호
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• pp.235-244
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• 1995

생쥐 배반포기 내부세포괴를 체외에서 분리 배양하여 분화가 억제된 내부세포괴 유래 증식세포를 미분화 상태에서 무한히 증식할 수 있는 전능성을 지닌 배아간세포(embryonic stem cell : ES cell)로 확립하고자 본 연구를 실시하였다. BCF1 생쥐 배반포를 10% FCS, 0.1mM nonessential amino acid, 0.1mM sodium pyruvate, 0.1mM 2-mercaptoethanol과 1,000U/ml LIF(세포분확억제인자)가 첨가된 DMEM 기초배양액에 mitomycin-C를 처리한 STO 단층배양세포에서 배양하여 분화가 억제된 내부세포괴 유래의 배아간세포를 분리하였다. 배반포를 STO 단층배양세포에서 4일간 배양하여 내부세포괴세포를 신선한 STO 단층배양세포에서 약 5일 간격으로 반복하여 계대배양을 실시하였다. 5차 계대배양후 뚜렷한 분화 양상없이 배양된 미분화 세포군에 대한 alkaline phosphatase (AP)염색과 체외분화능 검색을 실시한 결과 적색의 미분화 AP 양성반응이 확인되었으며 체외에서 배분화 형성이 유도됨에 따라 배양된 배아간세포주의 다능성 배아간세포 특성을 확인할 수 있었다.