• Reproductive and Developmental Biology
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• v.33 no.2
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• pp.107-111
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• 2009

The transfection efficiency of a transgene into pig and goat fetal fibroblast cells (PFF and GFF, respectively) was tested using co-transfection of a human tissue-type plasminogen activator (tPA) transgene and neomycin-resistant ($Neo^r$) gene, followed by G418 selection. To initially test G418 resistance, GFF and PFF were incubated in culture medium containing different concentration of G418 for 2 weeks, and cell survival was monitored over time. Based on the obtained results, the concentrations chosen for G418 selection were 800 ug/ml and 200 ug/ml for GFF and PFF, respectively. For co-transfection experiments, the pBC1/tPA and $Neo^r$ vectors were co-transfected into GFF and PFF ($1{\times}10^6$ cells in each case) using the FuGENE6 transfection reagent, and resistant colonies were obtained following 14 days of G418 selection. We obtained 96 and 93 drug-resistant colonies of GFF and PFF, respectively, only 54 and 39 of which, respectively, continued proliferating after drug selection. PCR-based screening revealed that 23 out of 54 analyzed GFF colonies and 5 out of 39 analyzed PFF colonies contained insertion of the tPA gene. Thus, the experimentally determined transfection efficiencies for tPA gene co-transfection with the $Neo^r$ gene were 42.6% for GFF and 12.8% for PFF. These findings suggest that co-transfection of a transgene with the $Neo^r$ gene can aid in the successful integration of the transgene into fetal fibroblast cells.

• Journal of Embryo Transfer
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• v.31 no.1
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• pp.1-7
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• 2016

Xenotransplantation involves multiple steps of immune rejection. The present study was designed to produce nuclear transfer embryos, prior to the production of transgenic pigs, using fibroblasts carrying transgenes human complement regulatory protein hCD59 and interleukin-18 binding protein (hIL-18BP) to reduce hyperacute rejection (HAR) and cellular rejection in pig-to-human xenotransplantation. In addition to the hCD59-mediated reduction of HAR, hIL-18BP may prevent cellular rejection by inhibiting the activation of natural killer cells, activated T-cell proliferation, and induction of $IFN-{\gamma}$. Transgene construct including hCD59 and ILI-18BP was introduced into miniature pig fetal fibroblasts. After antibiotic selection of double transgenic fibroblasts, integration of the transgene was screened by PCR, and the transgene expression was confirmed by RT-PCR. Treatment of human serum did not affect the survival of double-transgenic fibroblasts, whereas the treatment significantly reduced the survival of non-transgenic fibroblasts (p<0.01), suggesting alleviation of HAR. Among 337 reconstituted oocytes produced by nuclear transfer using the double transgenic fibroblasts, 28 (15.3%) developed to the blastocyst stage. Analysis of individual embryos indicated that 53.6% (15/28) of embryos contained the transgene. The result of the present study demonstrates the resistance of hCD59 and IL-18BP double-transgenic fibroblasts against HAR, and the usefulness of the transgenic approach may be predicted by RT-PCR and cytolytic assessment prior to actual production of transgenic pigs. Further study on the transfer of these embryos to surrogates may produce transgenic clone miniature pigs expressing hCD59 and hIL-18BP for xenotransplantation.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.1
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• pp.20-25
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• 2009

Xenotransplantation of pig organs into humans is a potential solution for the shortage of donor organs for transplantation. However, multiple immune barriers preclude its clinical application. In particular, the initial type of rejection in xenotransplantation is an acute cellular rejection by host $CD8^+$ cytotoxic T lymphocyte (CTL) cells that react to donor major histocompatibility complex (MHC) class I. The human cytomegalovirus (HCMV) glycoprotein Unique Short (US) 2 specifically targets MHC class I heavy chains to relocate them from the endoplasmic reticulum (ER) membrane to the cytosol, where they are degraded by the proteasome. In this study we transfected the US2 gene into minipig fetal fibroblasts and established four US2 clonal cell lines. The integration of US2 into transgenic fetal cells was confirmed using PCR and Southern blot assay. The reduction of Swine Leukocyte Antigen (SLA)-I by US2 was also detected using Flow cytometry assay (FACS). The FACS analysis of the US2 clonal cell lines demonstrated a substantial reduction in SLA-I surface expression. The level (44% to 76%) of SLA-I expression in US2 clonal cell lines was decreased relative to the control. In cytotoxicity assay the rate of $CD8^+$ T cell-mediated cytotoxicity was significantly reduced to 23.8${\pm}$15.1% compared to the control (59.8${\pm}$8.4%, p<0.05). In conclusion, US2 can directly protect against $CD8^+$-mediated cell lysis. These results indicate that the expression of US2 in pig cells may provide a new approach to overcome the CTL-mediated immune rejection in xenotransplantation.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.33-33
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• 2003

This study was conduct to compare the efficacy to produce male and female somatic cloned piglets. Maturation of porcine COCs was accomplished by incubation in NCSU-23 medium supplemented with 0.6 mM cysteine, 10% porcine follicular fluid, 1mM dibutyryl cyclic adenosine monophosphate (dbc-AMP, Sigma, USA), and 0.1 IU/ml human menopausal gonadotrophin (hMG, Teikokuzoki, Japan) for 20h and then cultured without dbcAMP and hMG for another 18 to 24 h. Female and male fetal cells were isolated from each fetus, cultured in ES-DMEM medium containing 10% FCS. Enucleated oocytes were fused with fetal fibroblasts (passage 4 to 15). Reconstructed embryos were cultured in NCSU-23 with 4 mg/ml BSA under mineral oil at 39$^{\circ}C$ in 5% $CO_2$ in air. A total of 12,328 nuclear-transferred embryos (1- to 4-cell stage) were surgically transferred into 69 surrogate gilts. Three recipients aborted during the period of conception. Three gilts delivered eleven female piglets, and five recipients gave rise to birth 22 male piglets. The average birth weigh of the cloned piglets was 1.52 kg (1.38~1.83 kg) in female piglets and 0.84 kg (0.45~1.25 kg) in male piglets. Alive cloned pigs was seven in female piglets (63.6%) and four in male piglets (18.2%). The other two recipients is ongoing. This study suggests that female-derived fetal cell as a nuclear donor has more capability on production of cloned piglets than male.

• Reproductive and Developmental Biology
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• v.28 no.1
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• pp.7-12
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• 2004

This study was performed to establish the effective culture condition for the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were cultured and passaged two times before use. A single cell was seeded in 96-well plates, cultured in medium supplemented with different concentrations of FBS, catalase or $\beta$-mercaptoethanol ($\beta$ME), and classified by cell size and morphology. Cells were passaged two times into 4-well dish before freezing. The establishment efficiencies were not different among different concentrations of FBS (0.3 to 5.1%). However, population doubling time (PDT) was significantly decreased by increasing the FBS concentration (P＜0.05). The establishment efficiency of $\beta$ME-added group (10.4%) was significantly higher than those of catalase-added and control groups (3.5%, and 3.5%, respectively, p＜0.05), and PDT was significantly decreased (23.6 vs 28.1, and 25.5 h, respectively, p＜0.05). However, catalase did not show a positive effect on the establishment efficiency. Cell size and morphology did not affect the establishment efficiency and PDT of clonal lines. The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 30% FBS and $\beta$ME.

• Reproductive and Developmental Biology
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• v.41 no.3
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• pp.57-63
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• 2017

Xenotransplantation is proposed as a solution to the problem of organ shortage. However, transplantation of xenogeneic organs induces an antigen-antibody reaction in ${\alpha}$-1,3-gal structure that are not present in humans and primates, and thus complement is also activated and organs die within minutes or hours. In this study, we used FasL gene, which is involved in the immune response of NK cell, and US11, which suppresses MHC Class I cell membrane surface expression, to inhibit cell mediated rejection in the interspecific immunity rejection, and also hDAF(CD55) was introduced to confirm the response to C3 complement. These genes were tranfeced into Korean native pig fetal fibroblasts using pCAGGS vector. And cytotoxicity of NK cell and human complement was confirmed in each cell line. The US11 inhibited the cytotoxicity of NK cell and, in addition, the simultaneous expression of US11 and Fas ligand showed excellent suppress to T-lymphocyte cytotoxicity, hDAF showed weak resistance to cytotoxicity of natural killer cell but not in CD8+ CTLs. Cytotoxicity study with human complement showed that hDAF was effective for reducing complement reaction. In this studies have demonstrated that each gene is effective in reducing immune rejection.

• Journal of Embryo Transfer
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• v.19 no.3
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• pp.201-208
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• 2004

This study was performed to examine the effects of catalase and $\beta$-mercaptoethanol ($\beta$ME) on the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were passaged two times before use. A single cell was seeded in 96-well plates and cultured in medium supplemented with or without catalase or $\beta$ ME. Cell colonies were passaged two times into 4-well dish. Cell lines with proliferating potential were classified as an established clonal cell line. In experience 1, the establishment efficiencies were examined by addition of catalase (100ng/$m\ell$) or $\beta$ME (100 uM) in culture medium. The establishment efficiency of $\beta$ME-added group (8.3％) was significantly higher than that of control group (3.2％, P<0.05). However, catalase did not have a positive efffct on the establishment efficiency. In experience 2, the establishment efficiencies were examined by addition of different concentrations of catalase (0-1,000 ng/$m\ell$) in culture medium. However, establishment efficiencies were not different among the different concentrations of catalase (0-2.6％). In experience 3. the establishment efficiencies were examined by addition of different concentrations of $\beta$ME(0-1,000 uM) in culture medium. The establishment efficiency was significantly higher in 100 uM $\beta$ME-added group (9.4％) compare to others (0-1.6％). The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 100uM $\beta$ME. However, catalase did not have a positive effect on the establishment efficiency.

• Reproductive and Developmental Biology
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• v.30 no.2
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• pp.119-124
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• 2006

The present study compared the developmental potential of cloned porcine embryos with mesenchymal stem cells (MSCs), fetal fibroblasts (FFs) and cumulus cells (CCs) by assessing the cleavage and blastocyst rate, total cell number, inner cell mass (ICM) ratio and apoptosis. MSCs were isolated by ficoll gradients from femur of -6 month old female pig, and maintained for primary cultures. FFs from a female fetus at ${\sim}30$ day of gestation were established, and CCs were obtained from cumulus oocyte complexes (COCs) aspirated from $3{\sim}6$ mm follicles in diameter. Donor cells at $3{\sim}4$ passage were employed for nuclear transfer (NT). COCs were matured and fertilized in vitro(IVF) as control. Cleavage rate was significantly (P<0.05) higher in IVF than in NT embryos with MSCs, FFs and CCs ($82.7{\pm}8.9%\;vs\;70.6{\pm}5.4,\;68.7{\pm}5.1\;and\;63.4{\pm}5.6%$, respectively). However, blastocyst rates in IVF and NT embryos derived from MSCs ($24.5{\pm}2.8\;and\;20.4{\pm}8.3%$) did not differ, but were significantly (P<0.05) higher than NT derived from FFs and CCs ($10.6{\pm}2.7\;and\;9.8{\pm}2.1%$). Total cell number and the ratio of ICM to total cells among blastocysts cloned from MSCs ($35.4{\pm}5.2\;and\;0.40{\pm}0.09%$, respectively) were significantly (P<0.05) higher than those from FFs and CCs ($24.9{\pm}6.2%\;vs\;0.19{\pm}0.16,\;23.6{\pm}5.5\;and\;0.17{\pm}0.16%$, respectively). Proportions of TUNEL positive cells in NT embryos from FFs and CCs ($6.9{\pm}1.5\;and\;7.4{\pm}1.7%$, respectively) were significantly (P<0.05) higher than in MSCs ($4.8{\pm}1.4%$) and IVF ($2.3{\pm}0.9%$). The results demonstrate that MSCs have a greater potential as donor cells than FFs and CCs in achieving enhanced production of cloned porcine embryos.