• Korean Journal of Animal Reproduction
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• v.12 no.1
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• pp.11-14
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• 1988

Utilizatin of primordial germ cell(PGC) as transferor of genetic materials is great potential in manipulating genes to promote genetic performances in chicken. This study explored that PGCs from early embryos as vehicle for molecular breeding strategles were isolated, these chromosomally marked donor PGCs were transplanted to germinal crescent of host embryos, and genetic materials of donor PGC were identified at the proliferative stage in host gonads.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.5 no.1
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• pp.116-125
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• 2005

Orthotopic liver transplantation is the treatment of choice for inherited metabolic diseases. However, the supply of donor organs is limiting and therefore many patients cannot benefit from this therapy. In contrast, hepatocytes can be isolated from a single donor liver. They can be transplanted into several recipients, and this procedure may help overcome the shortage of donor livers. A great deal of work with animal models indicates that hepatocytes transplanted into the liver or spleen can survive, function, and participate in the normal regenerative process. Recent clinical studies suggest that hepatocyte transplantation may be useful for bridging patients to whole organ transplantation and for providing metabolic support during liver failure and for replacing whole organ transplantation in certain inherited metabolic diseases. Nowadays, hepatocytes from various stem cells have been regarded as an another cell source for treatment of inherited metabolic diseases. Although cell therapy using stem cells for inherited metabolic disease patient has been accepted only as an experimental trial yet, hepatocytes from stem cells can solve a lot of obstacles in the treatment of inherited metabolic diseases.

• Reproductive and Developmental Biology
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• v.35 no.3
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• pp.197-201
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• 2011

This study was conducted to investigate the effects of donor cell treatments on the production of transgenic cloned piglets. Ear fibroblast cell obtained from NIH MHC Inbred minipig was used as control. The GalT knock-out/CD45 knock-in (GalT/CD46) transgenic cell lines were established and used as donor cells. The reconstructed GalT/CD46 embryos were surgically transferred into oviduct of naturally cycling surrogate sows (Landrace ${\times}$ Yorkshire) on the second day of standing estrus. Unlike control (1.2 kV/cm, 75.4%), the fusion rate of the GalT/CDl6 donor cells was significantly higher in 1.5 kV/cm, (84.5%) than that of 1.25 kV/cm, (20.2%) (p<0.01). When the number of the transferred embryos were more than 129, the pregnancy and delivery rates were increased to 13/20 (65%) and 5/20 (25%) compared to less then 100 group [1/6 (16.7%) and 0/6 (0%)], respectively. To analyze the effect of donor cell culture condition on pregnancy and delivery rates, the GalT/CD46 donor cells were cultured with DMEM or serum reduced medium. In serum reduced medium group, the pregnancy and delivery rates were improved to 8/12 (66.7%) and 5/12 (41.7%) compared to DMEM group [3/7 (42.9%) and 0/7 (0%)], respectively. In conclusion, it can be postulated that an appropriate fusion condition and culture system is essential factors to increase the efficiency of the production of transgenic cloned piglets.

• Reproductive and Developmental Biology
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• v.35 no.2
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• pp.175-183
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• 2011

The present study compared the developmental potential, telomerase activity and transcript levels of X-linked genes (ANT3, HPRT, MeCP2, RPS4X, XIAP, XIST and ZFX) in the bovine somatic cell nuclear transfer (SCNT) embryos derived from different age and cell cycle of female donor nucleus. In experiment 1, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was slightly increased in embryos cloned with fetal fibroblasts compared to those with adult fibroblasts, but there was no significantly (p<0.05) differences. Telomerase activity was also similar in blastocysts cloned with fetal and adult fibroblasts. Up-regulated RPS4X and down-regulated MeCP2, XIAP, and XIST transcript level were observed in blastocysts cloned with adult fibroblasts, compared to those with fetal fibroblasts. In experiment 2, the fusion rate, cleavage rate to 2-cell stage, developmental rate to blastocyst stage, and the mean number of total and ICM cells was significantly (p<0.05) increased in embryos cloned with fetal fibroblasts at early G1 phase of the cell cycle, compared to those of fetal fibroblasts at late G1 phase. DNMT1 transcript was observed to significantly (p<0.05) increased in the fetal fibroblasts at 3 hrs after trypsin treatment of confluent culture. Further, level of telomerase activity and transcribed X-linked genes was also significantly (p<0.05) higher in the early G1 SCNT blastocysts than those of late G1. The results imply that fetal fibroblasts at early G1 phase induces the enhanced developmental potential and up-regulated telomerase activity and X-linked gene, but aberrant transcript pattern of X-linked genes may be displayed in the SCNT embryos.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.73-82
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• 1995

large scale production of cloned embryos requires the technology of multiple generation nuclear transplantation(NT) using NT embryos as the subsequent donor nuclei. The purposes of this study were producing the second generation cloned rabbit embryos, and also to determine the electrofusion rate and in vitro developmental potential comparatively in the cloned embryos of the first and second NT generation. The embryos of 16-cell stage were collected from the mated does by flushing oviducts with Dulbecco's phosphate buffered saline(D-PBS) containing 10% fetal calf serum(FCS) at 47 hours after hCG injection In the first generation NT, the nuclear donor embryos were synchronized in the phase of Gi /S transition of 32-cell stage. The first generation NT embryos which were developed to 8-cell were synchronized in Gi /S transition phase of the following 16-cell stage and used as donor nuclei for second generation Synchronization of the cell cycle of blastomeres was induced, first, using an inhibitor of microtuble polymerization, colcemid for 10 hours to arrest blastomeres in M phase, and secondly, using a DNA synthesis inhibitor, aphidicolin for 1.5 to 2 hours to arrest them in Gi /S transition boundary. The recipient cytoplasms were obtained by removing the nucleus and the first polar body from the oocytes collected at 14 hours after hCG injection. The separated donor blastomeres were injected into the enucleated recipient oocytes by micromanipulation and were electrofused by electrical stimulation of three pulses for 60 $\mu$sec at 1.25 kV /cm in 0.28 M rnannitol solution The fused oocytes were co-cultured with a monolayer of rabbit oviductal epithelial cells in M-199 solution containing 10% FCS for 120 hours at 39$^{\circ}C$ in a 5% $CO_2$ incubator. Following in vitro culture of the first and second generation cloned embryos to blastocyst stage, they were stained with Hoechst 33342 dye for counting the number of blastomeres by fluorescence microscopy. The results obtained were summarized as follows: 1. The electrofusion rate was found to be similar as 79.4 and 91.5% in the first and second generation NT rabbit embryos, respectively. 2. The in vitro developmental potential to blastocyst stage of the second generation NT embryos (23.3%) was found significantly(p<0.05) lower, compared with that of the first generation NT embryos (56.8%). 3. The mean blastomeres counts of embryos developed to blastosyst stage following in vitro culture for 120 hours and also their daily cell cycles during the culture period were decreased significantly (p<0.05) to 104.3 cells and 1.33 cylces in the second NT generation, compoared with 210.4 cells and 1.54 cycles in the first NT generation, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.192.1-192.1
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• 2014

We report solution-processed organic trilayer solar cells consisting of poly (3-hexylthiophene) (P3HT), a conjugated polyelectrolyte (CPE) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), wherein the effect CPE layer thickness on device properties was investigated. The current-voltage characteristics under illumination and dark as well as photoluminescence were characterized using various concentrations (0.02, 0.1, and 0.3wt%) of to deposit the CPE interlayer between the donor and acceptor layers. We also investigated the influence of molecular dipole moments in the trilayer solar cells by external stimuli. These results provide an experimental approach for investigating the influence of interfacial dipoles on solar cell parameters when placed between the donor and acceptor and allow us to obtaining fundamental information about the donor/acceptor interface in organic solar cells.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.2
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• pp.112-116
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• 2002

Effects of artificial electron donors to deliver reducing power on enzymic denitrification were investigated using nitrate reductase and nitrite reductase obtained from Ochrobactrum antroyi. The activity of nitrite reductase in the soluble portion was almost the same as that in the precipitated portion of the cell extract. Nitrate removal efficiency was higher with benzyl viologen than with methyl viologen or NADH as an artificial electron donor. The turn-over numbers of nitrate and nitrite reductase were 14.1 and 1.9 umol of nitrogen reduced/min$.$mg cell extracts, respectively when benzyl viologen was used as an electron donor.

• Reproductive and Developmental Biology
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• v.31 no.2
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• pp.127-131
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• 2007

Embryonic germ (EG) cells are undifferentiated stern cells isolated from cultured primordial germ cells (PGC). These cells share many characteristics with embryonic stem cells including morphology and pluripotency. Undifferentiated porcine EG cell lines demonstrating capacities of differentiation both in vitro and in vivo have been established. Since EG cells can be cultured indefinitely in an undifferentiated state, whereas somatic cells in primary culture are often unstable and have limited lifespan, EG cells may provide inexhaustible source of karyoplasts in nuclear transfer (NT). In this study the efficiencies of NT using porcine EG and fetal fibroblast cells were compared. Two different techniques were used to perform NT. With conventional NT procedure (Roslin method) involving fusion of donor cells with enucleated oocytes, the rates of development to the blastocyst stage in EG and somatic cell NT were 16.8% (59/351) and 14.5% (98/677), respectively. In piezo-driven microinjection (Honolulu method) of donor nuclei into enucleated oocytes, the rates of blastocyst formation in EG and somatic cell NT were 11.9% (15/126) and 9.4% (9/96), respectively. Regardless of NT methods used in this study, EG cell NT gave rise to comparable rate of blastocyst development to somatic cell NT. Overall, EG cells can be used as karyoplast donor in NT procedure, and embryos can be produced by EG cell NT that may be used as an alternative to conventional somatic cell NT.

• IMMUNE NETWORK
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• v.10 no.2
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• pp.46-54
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• 2010

Background: Graft-versus-host disease (GVHD) is initiated when alloreactive donor T cells are primed by host APCs to undergo clonal expansion and maturation. Since there is a controversy regarding the role of nonhematopoietic cells in GVHD, we wanted to investigate the influence of MHC disparity on nonhematopoietic cells on the pathogenesis of GVHD in the MHC-haplomismatched C57BL/6 ($H-2^b$) or DBA/2 $(H-2^b){\rightarrow}$unirradiated ($C57BL/6{\times}DBA/2$) $F_1(BDF_1;\;H-2^{b/d})$ murine model of acute GVHD (aGVHD) or chronic GVHD (cGVHD). Methods: We generated ($BDF_1{\rightarrow}C57BL/6$), ($BDF_1{\rightarrow}DBA/2$), and ($BDF1{\rightarrow}BDF_1$) chimeras and examined GVHD-related parameters and donor cell engraftment in those chimeras. Results: Using this experimental system, we found that 1) severe aGVHD across MHC Ag barrier depends on the expression of nonhematopoietically rather than hematopoietically derived alloAgs for maximal GVHD manifestations; 2) host APCs were sufficient to break B cell tolerance to self molecules in cGVHD, whereas host APCs were insufficient to induce autoimmunity in aGVHD; 3) donor cell engraftment was greatly enhanced in the host with MHC-matched nonhematopoietic cells. Conclusion: Taken together, our results provide an insight into how MHC disparity on GVHD target organs contribute to the pathogenesis of GVHD.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.109-109
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• 2003

Even though success in birth of live offspring from nuclear transfer(NT) using somatic cells in many species, detailed information on processes or mechanisms of development are not well known. Cytoplasm of bovine oocyte has been known to support the development of nuclear transferred embryos using nuclear donor cells from different species. Therefore, interspecies NT might be used to find answers of some questions in basic aspect of nuclear transfer In this study, we examined the developmental potential of reconstructed embryos when bovine oocyte as a cytoplasm recipient and mouse embryonic fibroblast as a nuclear donor were used. The nuclear transfer units were aliocated in Group 1 (murine block media and normal media) and Group 2. (bovine block media and normal media). NT units were not blocked at 2-cell stage regardless of types of medium. On mouse media, poor development of interspecies NT units was observed compared to bovine media. However, as NT units cultured in bovine normal medium, embryos developed over 8-cell stage. Further studies performed to increase the developmental rate in condition of antioxidant treatment. Despite low development, bovine-murine interspecies nuclear transferred embryos could develop to blastocysts and they showed that blastocyts rate of antioxidant group was superior to those of non-antioxidant group. Next, we investigated gene expression pattern which is carried out for zygotic activation. The Xist gene is expressed in female mouse embryo after zygotic activation of 4-cell stage. But interspecies nuclear transferred embryos do not express Xist gene at 4-cell stage. As a result, it is suggested that the bovine cytoplasm controls the early preimplantation development in interspecies NT However, the development of later stages might require genomic control from transferred donor nucleus. Therefore, even though the involvement of several other factors such as mitochondrial incompatibility, effective development of embryos produced by interspecies NT requires proper genomic activation of donor nucleus after overcoming the cytoplasmic control of recipient oocytes.