• The Korean Journal of Physiology and Pharmacology
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• v.7 no.5
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• pp.261-266
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• 2003

Type 1 diabetes is an organ-specific autoimmune disease caused by the cytotoxic T cells-mediated destruction of the insulin-producing beta cells in the Langerhans pancreatic islets. Hepatocyte growth factor (HGF) is a potent mitogen and a promoter of proliferation of insulin producing beta cells of pancreatic islets. To study the role of HGF via viral vector in the development of streptozotocin (STZ)-induced diabetes in mice, we have developed an adenoviral vector genetically engineered to carry the gene for human HGF (hHGF) and evaluate the change of blood glucose, insulin level, and insulin-secreting beta cells of pancreatic islets. We demonstrate that the treatment with hHGF gene prevented the development of STZ-induced diabetes and increased serum insulin level to above normal range. Furthermore, it preserved pancreatic beta cells from destruction. These in vivo results may support previous findings that HGF is insulinotropic agent for beta cells and HGF treatment renders the cells to be resistant to the development of diabetes from STZ administration. We suggest that an adenoviral mediated hHGF gene therapy is a good candidate for the prevention and treatment of type 1 diabetes.

• Plant Biotechnology Reports
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• v.1 no.1
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• pp.19-25
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• 2007

To develop an efficient screening method for detection of the transgene in Chinese cabbage (Brassica rapa spp. pekinensis) utilizing Basta spray, optimal conditions for Basta application were examined in this study. Two transgenic Chinese cabbage lines were obtained through Agrobacterium-mediated transformation and used as transgenic positive controls in the Basta screening experiment. Differential concentrations of glufosinate-ammonium were sprayed into three different growth stages of 12 commercial Chinese cabbage cultivars. The results showed that no plants could survive higher than 0.05% glufosinate-ammonium, and plants at the 2-3 leaf stage were most vulnerable to glufosinate-ammonium. On the other hand, no damage was observed in the transgenic control plants. Reliability of the Basta spray method was proven by showing perfect co-segregation of the tolerance to glufosinate-ammonium and the presence of the bar gene in T₁ segregating populations of the transgenic lines, as revealed by both PCR and Southern blot analyses. Using the developed Basta screening method, we tried to investigate the transgene flow through pollen dispersal, but failed to detect any transgene-containing non-transgenic Chinese cabbages whose parents had been planted adjacent to transgenic Chinese cabbages in field conditions. However, the transgene was successfully detected using Basta spray from the non-transgenic plants bearing the transgene introduced by hand-pollination. Since the Basta spray method developed in this study is easy to apply and economical, it will be a valuable tool for understanding the mechanism of gene flow through pollen transfer and for establishing a biosafety test protocol for genetically modified (GM) Chinese cabbage cultivars.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.804-811
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• 2024

Foamy viruses (FVs) are generally recognized as non-pathogenic, often causing asymptomatic or mild symptoms in infections. Leveraging these unique characteristics, FV vectors hold significant promise for applications in gene therapy. This study introduces a novel platform technology using a pseudo-virus with single-round infectivity. In contrast to previous vector approaches, we developed a technique employing only two vectors, pcHFV lacking Env and pCMV-Env, to introduce the desired genes into target cells. Our investigation demonstrated the efficacy of the prototype foamy virus (PFV) dual-vector system in producing viruses and delivering transgenes into host cells. To optimize viral production, we incorporated the codon-optimized Env (optEnv) gene in pCMV-Env and the Woodchuck Hepatitis Virus Posttranscriptional Regulatory Element (WPRE) at the 3' end of the transgene in the transfer vector. Consequently, the use of optEnv led to a significant enhancement in transgene expression in host cells. Additionally, the WPRE exhibited an enhancing effect. Furthermore, the introduced EGFP transgene was present in host cells for a month. In an effort to expand transgene capacity, we further streamlined the viral vector, anticipating the delivery of approximately 4.3 kbp of genes through our PFV dual-vector system. This study underscores the potential of PFVs as an alternative to lentiviruses or other retroviruses in the realm of gene therapy.

• Korean Journal of Animal Reproduction
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• v.27 no.1
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• pp.25-34
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• 2003

Human thrombopoietin (hTPO) is a cytokine that plays a central role in megakaryopoiesis. To direct hTPO expression in the mammary gland, an expression vector was constructed by combining the promoter of bovine beta-casein gene, cDNA of hTPO and neomycin resistance gene (pBT-L neo). Fibroblast cells derived from cow's ear skin tissue were transfected with the expression vector (pBT-L neo) using Lipofectamine. Transfected cells resistant to G418 trea？nt were cultured to form the colonies for more than 2 weeks. The transformed colonies identified by PCR were further expanded prior to nuclear transfer. Reconstructed oocytes with transformed cells were electrofused, activated using calcium ionophore and 6-DMAP, and cultured in vitro for 7 days. Of 35 cell colonies analyzed by PCR, 29 colonies (82.9%) were positive for the hTPO gene. Cleavage and developmental rates to the blastocyst stage of reconstructed embryos with the transformed cells were 65.1% and 23.8%, respectively Of 29 blastocysts that developed from reconstructed embryos with the transformed cells, 27 embryos (93.1%) were transgenic. These results indicate that transgenic bovine embryos can be efficiently produced by somatic cell nuclear transfer using transformed cells.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.319-324
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• 2007

This study was conducted to evaluate the persistence of DNA in the transgenic chili pepper resistant to cucumber mosaic virus (CMV) in the field condition. We analyzed the persistence of genes in the leaf samples obtained from two field conditions, below and above soil. Transgenic and non-transgenic leaf tissues were buried in the soil at a depth of 10 cm or placed on the soil surface. Qualitative and quantitative PCR analysis showed that the amount of transferred genes from the transgenic peppers below and above soil was dropped to 28.3-42.7% one month after buried and it was rapidly reduced to 0.9-3.3% after two months. The transgenes were not detected three to four month after buried. In addition, DNA of the leaves placed below soil decomposed about 8%more than those on soil surface. The gene transfer from decomposing leaves of the transgenic pepper to soil was investigated by PCR analysis with the soil attached to the samples. The PCR result indicated that the gene transfer from the transgenic pepper to soil was not occurred.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.220-220
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• 2004

The purpose of this study was to development of transgenic cow using the nuclear transfer. To secrete hFSH in urea, the vector was constructed with UPII promoter. The fetal fibroblast cells (KbFF) were constructed from pregnant day 45 male fetus. The hFSH genes were cotransfected with pcDNA3 (neo) vector to KbFF cells by electroporation. (omitted)

• Korean Journal of Animal Reproduction
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• v.13 no.2
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• pp.98-104
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• 1989

Successful techniques of in vitro fertilization(IVF) are valuable for studying the process of fertilization and for developing economical procedures for gene and nuclear transfer in farm animals. To date, bovine IVF system has been developed with oocytes in vitro or vitro, but the resulting zygotes exhibit limited embryonic development after in vitro culture. Even though in vitro matured oocytes achieved high fertilization and cleavage rates, these embryos appear extremly low rate of pregnancies when transferred to synchronized recipients. Development of early bovine embryos in vitro is generally arrested at the 8-to 16-cell stage. However, recent use of somatic cells such as trophoblastic vesicle, granulosa and oviduct epithelial cell for co-culture with early bovine embryos has proven effective for development of embryos, matured and fertilized in vitro, past the in vitro cell blocks. These factors clearly indicate the value of the co-culture system in promoting development of bovine oocytes matured and fertilized in vitro to morula or blastocyst stage in vitro. In addition, co-culture system may beome a tool for evaluation of viability of ova that have been manipulated by procedures such as splitting, microinjection and nuclear transfer.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.64-65
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.64-64
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• 2003

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2006.10a
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• pp.30-31
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• 2006