• Proceedings of the PSK Conference
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• 2003.10b
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• pp.99.2-99.2
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• 2003

One of the major limitations in using adenoviral vector for gene therapy is inefficient infection of host cells. The presence of coxsackievirus and adenovirus receptor (CAR) and ${\alpha}$-integrin on cell surfaces is required for efficient adenovirus infection. In this study, we investigated the effect of trichostatin A, a histone deacetylase inhibitor, on transfection efficiency after transduction of adenovirus mediated p16$\^$INK4a/ gene transfer. In our previous study, p16$\^$INK4a/ tumor suppressor gene transfer in the non-small cell lung cancer cells (A549 cells) by transduction of recombinant adenovirus (Ad5CMV-p16) resulted in significant inhibition of cancer cell proliferation. (omitted)

• IMMUNE NETWORK
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• v.6 no.4
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• pp.192-198
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• 2006

Background: Investigating strategy to enhance efficiency of gene transfer via adenovirus is critical to sustain gene expression in targeted cells or tissues to regulate immune responses. However, the use of adenovirus as a gene delivery method has been limited by the native tropism of the virus. In this study, the critical parameter is to improve the efficient binding of viral particles to the plasma membrane prior to cellular uptake. Methods: Human immunodeficiency virus (HIV-1) trans-acting activator of transcription (TAT), a protein transduction domain, was fused to the ectodomain of the coxsackie-adenovirus receptor (CAR). The CAR-TAT protein was produced from a Drosophila Schneider 2 cells (S2) transfected with CAR-TAT genes. The function of CARTAT was analyzed the efficiency of adenoviral gene transfer by flow cytometry, and then immunizing AdVGFP with CAR-TAT was transduced on dendritic cells (DCs). Results: S2 transfectants secreting CAR-TAT fusion protein has been stable over a period of 6 months and its expression was verified by western blot. Addition of CAR-TAT induced higher transduction efficiency for AdVGFP at every MOI tested. When mice were vaccinated with DC of which adenoviral transduction was mediated by CAR-TAT, the number of IFN-${\gamma}$ secreting T-cells was increased as compared with those DCs transduced without CAR-TAT. Conclusion: Our data provide evidence that CAR-TAT fusion protein enhances adenoviral transduction and immunogenecity of transgenes on DCs and may influence on the development of adenoviral-mediated anti-tumor immunotherapy.

• BMB Reports
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• v.44 no.10
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• pp.647-652
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• 2011

The protein transduction domains have been reported to have potential to deliver the exogenous molecules, including proteins, to living cells. However, poor transduction of proteins limits therapeutic application. In this study, we examined whether imipramine could stimulate the transduction efficiency of PEP-1 fused proteins into astrocytes. PEP-1-catalase (PEP-1-CAT) was transduced into astrocytes in a time- and dose-dependent manner, reducing cellular toxicity induced by $H_2O_2$. Additionally, the group of PEP-1-CAT + imipramine showed enhancement of transduction efficiency and therefore increased cellular viability than that of PEP-1-CAT alone. In the gerbil ischemia models, PEP-1-CAT displayed significant neuroprotection in the CA1 region of the hippocampus. Interestingly, PEP-1-CAT + imipramine prevented neuronal cell death and lipid peroxidation more markedly than PEP-1-CAT alone. Therefore, our results suggest that imipramine can be used as a drug to enhance the transduction of PEP-1 fusion proteins to cells or animals and their efficacies against various disorders.

• BMB Reports
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• v.44 no.5
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• pp.329-334
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• 2011

Many proteins with poor transduction efficiency were reported to be delivered to cells by fusion with protein transduction domains (PTDs). In this study, we investigated the effect of levosulpiride on the transduction of PEP-1 ribosomal protein S3 (PEP-1-rpS3), and examined its influence on the stimulation of the therapeutic properties of PEP-1-rpS3. PEP-1-rpS3 transduction into HaCaT human keratinocytes and mouse skin was stimulated by levosulpiride in a manner that did not directly affect the cell viability. Following 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice, levosulpiride alone was ineffective in reducing TPA-induced edema and in inhibiting the elevated productions of inflammatory mediators and cytokines, such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1${\beta}$, and tumor necrosis factor-${\alpha}$. Anti-inflammatory activity by PEP-1-rpS3 + levosulpiride was significantly more potent than by PEP-1-rpS3 alone. These results suggest that levosulpiride may be useful for enhancing the therapeutic effect of PEP-1-rpS3 against various inflammatory diseases.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1613-1619
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• 2008

It has been reported that Tat-SOD can be directly transduced into mammalian cells and skin and acts as a potential therapeutic protein in various diseases. To isolate the compound that can enhance the transduction efficiency of Tat-SOD, we screened a number of natural products. 3-O-[$\beta$-D-Glucopyranosyl(1$\rightarrow$4)-$\alpha$-L-arabinopyranosyll-hederagenin (OGAH) was identified as an active component of Fatsia japonica and is known as triterpenoid glycosides (hederagenin saponins). OGAH enhanced the transduction efficiencies of Tat-SOD into HeLa cells and mice skin. The enzymatic activities in the presence of OGAH were markedly increased in vitro and in vivo when compared with the controls. Although the mechanism is not fully understood, we suggest that OGAH, the active component of Fatsia japonica, might change the conformation of the membrane structure and it may be useful as an ingredient in anti-aging cosmetics or as a stimulator of therapeutic proteins that can be used in various disorders related to reactive oxygen species (ROS).

• Molecules and Cells
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• v.45 no.7
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• pp.435-443
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• 2022

In response to environmental changes, signaling pathways rewire gene expression programs through transcription factors. Epigenetic modification of the transcribed RNA can be another layer of gene expression regulation. N⁶-adenosine methylation (m⁶A) is one of the most common modifications on mRNA. It is a reversible chemical mark catalyzed by the enzymes that deposit and remove methyl groups. m⁶A recruits effector proteins that determine the fate of mRNAs through changes in splicing, cellular localization, stability, and translation efficiency. Emerging evidence shows that key signal transduction pathways including TGFβ (transforming growth factor-β), ERK (extracellular signal-regulated kinase), and mTORC1 (mechanistic target of rapamycin complex 1) regulate downstream gene expression through m⁶A processing. Conversely, m⁶A can modulate the activity of signal transduction networks via m⁶A modification of signaling pathway genes or by acting as a ligand for receptors. In this review, we discuss the current understanding of the crosstalk between m⁶A and signaling pathways and its implication for biological systems.

• Molecules and Cells
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• v.24 no.1
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• pp.125-131
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• 2007

von Willebrand factor (vWF) is a multimeric glycoprotein which functions within the coagulation system. It colocalizes with factor VIII (FVIII) by non-covalent interaction and alters its intracellular trafficking. vWF is also instrumental in maintaining the stability of secreted FVIII. The principal objective of this study was to generate a lentivirus-based vWF expression vector for gene therapy of hemophilia A. We inserted a vWF of 8.8 Kb into a lentiviral vector thereby producing VSV-G-pseudotyped vEx52. However, its titer was quite low, presumably because the length of vWF gene exceeds the size limit of the lentiviral vector. In order to overcome the low-titer, we concentrated the vEx52 and thus increased the efficiency of transduction approximately 6-fold with $1/100^{th}$ of the volume. However, as concentration requires an additional laborious step, we attempted to enhance the transduction efficiency by deleting exons 24-46 and 29-46 in pRex52 to construct pRex23 and pRex28, and in pvEx52, yielding pvEx23 and pvEx28, respectively. The transfected pRex52 had a profound effect on the activity of secreted FVIII, and this activity declined as domains of vWF were deleted. However, when the domain-deleted vWF-lentiviruses were transduced into K562 cells, the vEx28 increased the activity of the secreted FVIII compared to what was observed with vEx52. This result is probably due to higher efficiencies of transduction and expression while retaining the essential domains required for proper interaction with FVIII.

• Journal of Animal Reproduction and Biotechnology
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• v.38 no.4
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• pp.199-208
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• 2023

Background: Canine induced pluripotent stem cells (iPSCs) are an attractive source for veterinary regenerative medicine, disease modeling, and drug development. Here we used vitamin C (Vc) to improve the reprogramming efficiency of canine iPSCs, and its functions in the reprogramming process were elucidated. Methods: Retroviral transduction of Oct4, Sox2, Klf4, c-Myc (OSKM), and GFP was employed to induce reprogramming in canine fetal fibroblasts. Following transduction, the culture medium was subsequently replaced with ESC medium containing Vc to determine the effect on reprogramming activity. Results: The number of AP-positive iPSC colonies dramatically increased in culture conditions supplemented with Vc. Vc enhanced the efficacy of retrovirus transduction, which appears to be correlated with enhanced cell proliferation capacity. To confirm the characteristics of the Vc-treated iPSCs, the cells were cultured to passage 5, and pluripotency markers including Oct4, Sox2, Nanog, and Tra-1-60 were observed by immunocytochemistry. The expression of endogenous pluripotent genes (Oct4, Nanog, Rex1, and telomerase) were also verified by PCR. The complete silencing of exogenously transduced human OSKM factors was observed exclusively in canine iPSCs treated with Vc. Canine iPSCs treated with Vc are capable of forming embryoid bodies in vitro and have spontaneously differentiated into three germ layers. Conclusions: Our findings emphasize a straightforward method for enhancing the efficiency of canine iPSC generation and provide insight into the Vc effect on the reprogramming process.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.3
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• pp.112-119
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• 2013

Objectives: This study investigated the question of whether adenoviral magnetofection can be a suitable method for increasing the efficacy of gene delivery into bone marrow stromal cell (BMSC) and for generation of a high level of bone morphogenic protein (BMP) secretion at a minimized viral titer. Materials and Methods: Primary BMSCs were isolated from C57BL6 mice and transduced with adenoviral vectors encoding ${\beta}$ galactosidase or BMP2 and BMP7. The level of BMP secretion, activity of osteoblast differentiation, and cell viability of magnetofection were measured and compared with those of the control group. Results: The expression level of ${\beta}$ galactosidase showed that the cell transduction efficiency of AdLacZ increased according to the increased amount of magnetic nanoparticles. No change in cell viability was observed after magnetofection with 2 ${\mu}L$ of magnetic nanoparticle. Secretion of BMP2 or BMP7 was accelerated after transduction of AdBMP2 and 7 with magnetofection. AdBMP2 adenoviral magnetofection resulted in up to 7.2-fold higher secretion of BMP2, compared with conventional AdBMP2-transduced BMSCs. Magnetofection also induced a dramatic increase in secretion of BMP7 by up to 10-fold compared to the control. Use of only 1 multiplicity of infection (moi) of magnetofection with adenoviral transduction of AdBMP2 or AdBMP7 resulted in significantly higher transgene expression compared to 20 moi of conventional adenoviral transduction. Conclusion: Magnetic particle-mediated gene transudation is a highly efficient method of gene delivery to BMSCs. Magnetofection can lower the amount of viral particles while improving the efficacy of gene delivery.

• BMB Reports
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• v.37 no.3
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• pp.376-382
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• 2004

The Epstein-Barr-transformed B lymphoblastoid cell lines, LCL, which express antigens, are potential antigen-presenting cells (APCs) for the induction of cytotoxic T lymphocytes in vitro. However, transfecting LCL with subsequent selection by antibiotics is notoriously difficult because the plating efficiencies of LCL are reported to be 1% or less. Therefore, this study investigated the optimal conditions for increasing the transduction efficiency of a recombinant adenovirus to LCL for use as a source of APCs. The transduction efficiencies were < 13% (SD $\pm$ 2.13) at a multiplicity of infection (MOI) of 100, while it was increased to 28% (SD $\pm$ 9.43) at an MOI of 1000. Moreover, its efficiencies to LCL that expressed the coxsackie adenovirus receptor were increased to 60% (SD $\pm$ 6.35) at an MOI of 1000, and were further increased to 70% (SD $\pm$ 4.56) when combined with the centrifugal method. The cationic liposome or anionic polymer had no effect on the transduction efficiency when compared to that of the centrifugal method. These results may be used as a convenient source of target cells for a CTL assay and/or autologous APCs for the induction of the in vitro CTL responses that are specific to viral and tumor antigens.