• 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.

• Journal of Life Science
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• v.27 no.7
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• pp.840-848
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• 2017

Proper intracellular transport is essential for normal cell function. Intracellular transport is mediated by microtubule-dependent molecular motor proteins, as well as kinesin and cytoplasmic dynein, which move their cargo along long, microtubule tracks in cells. Kinesins are ATP-dependent plus-end-directed motor proteins in the intracellular transport of organelles, vesicles, RNA complexes, and protein complexes. The mislocalization of these different types of cargo has been linked to cell dysfunction and degeneration. The cargo transport of kinesins can be described by the following steps: binding to the appropriate cargo and/or adaptor proteins, activation of the kinesin's motility and movement along the microtubule, and the release of the cargo at the correct destination. Recently, several studies have revealed the mechanisms for the regulation of kinesin motor activity, including cargo loading and unloading. Intracellular cargo transport is also modulated by adaptor proteins, which link the kinesins to their cargo. The regulatory proteins, which include protein kinases and phosphatases, regulate kinesin motor activity directly through the phosphorylation or dephosphorylation of kinesins and indirectly through the modification of adaptor proteins, such as c-Jun NH-terminal kinase-interacting proteins, or of the microtubule network. These findings lay the groundwork for understanding how kinesins are differentially engaged in intracellular cargo transport. In addition, understanding the regulatory mechanisms of each kinesin is an area of key interest within cell biology and neurophysiology. In this study, we reviewed kinesins' regulation proteins and discuss how their regulation affects cargo recognition and transport.

• IMMUNE NETWORK
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• v.23 no.6
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• pp.48.1-48.21
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• 2023

Mesenchymal stromal/stem cells (MSCs) possess immunoregulatory properties and their regulatory functions represent a potential therapy for acute lung injury (ALI). However, uncertainties remain with respect to defining MSCs-derived immunomodulatory pathways. Therefore, this study aimed to investigate the mechanism underlying the enhanced effect of human recombinant bone morphogenic protein-2 (rhBMP-2) primed ES-MSCs (MSC^BMP2) in promoting Tregs in ALI mice. MSC were preconditioned with 100 ng/ml rhBMP-2 for 24 h, and then administrated to mice by intravenous injection after intratracheal injection of 1 mg/kg LPS. Treating MSCs with rhBMP-2 significantly increased cellular proliferation and migration, and cytokines array reveled that cytokines release by MSC^BMP2 were associated with migration and growth. MSC^BMP2 ameliorated LPS induced lung injury and reduced myeloperoxidase activity and permeability in mice exposed to LPS. Levels of inducible nitric oxide synthase were decreased while levels of total glutathione and superoxide dismutase activity were further increased via inhibition of phosphorylated STAT1 in ALI mice treated with MSC^BMP2. MSC^BMP2 treatment increased the protein level of IDO1, indicating an increase in Treg cells, and Foxp3⁺CD25⁺ Treg of CD4⁺ cells were further increased in ALI mice treated with MSC^BMP2. In co-culture assays with MSCs and RAW264.7 cells, the protein level of IDO1 was further induced in MSC^BMP2. Additionally, cytokine release of IL-10 was enhanced while both IL-6 and TNF-α were further inhibited. In conclusion, these findings suggest that MSC^BMP2 has therapeutic potential to reduce massive inflammation of respiratory diseases by promoting Treg cells.

• Tuberculosis and Respiratory Diseases
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• v.80 no.1
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• pp.77-82
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• 2017

Background: Delayed hypersensitivity plays a large role in the pathogenesis of tuberculous pleural effusion (TPE). Macrophages infected with live Mycobacterium tuberculosis (MTB) increase the levels of adenosine deaminase2 (ADA2) in the pleural fluid of TPE patients. However, it is as yet unclear whether ADA2 can be produced by macrophages when challenged with MTB antigens alone. This study therefore evaluated the levels of ADA2 mRNA expression, using monocyte-derived macrophages (MDMs) stimulated with MTB antigens. Methods: Purified monocytes from the peripheral blood mononuclear cells of healthy volunteers were differentiated into macrophages using granulocyte-macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF). The MDMs were stimulated with early secretory antigenic target protein 6 (ESAT6) and culture filtrate protein 10 (CFP10). The mRNA expression levels for the cat eye syndrome chromosome region, candidate 1 (CECR1) gene encoding ADA2 were then measured. Results: CECR1 mRNA expression levels were significantly higher in MDMs stimulated with ESAT6 and CFP10, than in the unstimulated MDMs. When stimulated with ESAT6, M-CSF-treated MDMs showed more pronounced CECR1 mRNA expression than GM-CSF-treated MDMs. Interferon-${\gamma}$ decreased the ESAT6- and CFP10-induced CECR1 mRNA expression in MDMs. CECR1 mRNA expression levels were positively correlated with mRNA expression of tumor necrosis factor ${\alpha}$ and interleukin 10, respectively. Conclusion: ADA2 mRNA expression increased when MDMs were stimulated with MTB antigens alone. This partly indicates that pleural fluid ADA levels could increase in patients with culture-negative TPE. Our results may be helpful in improving the understanding of TPE pathogenesis.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1075-1083
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• 2015

Adipose tissue deposited within muscle fibers, known as intramuscular fat (IMF or marbling), is a major determinant of meat quality and thereby affects its economic value. The biological mechanisms that determine IMF content are therefore of interest. In this study, 48 genes involved in the bovine peroxisome proliferator-activated receptor signaling pathway, which is involved in lipid metabolism, were investigated to identify candidate genes associated with IMF in the longissimus dorsi of Hanwoo (Korean cattle). Ten genes, retinoid X receptor alpha, peroxisome proliferator-activated receptor gamma (PPARG), phospholipid transfer protein, stearoyl-CoA desaturase, nuclear receptor subfamily 1 group H member 3, fatty acid binding protein 3 (FABP3), carnitine palmitoyltransferase II, acyl-Coenzyme A dehydrogenase long chain (ACADL), acyl-Coenzyme A oxidase 2 branched chain, and fatty acid binding protein 4, showed significant effects with regard to IMF and were differentially expressed between the low- and high-marbled groups (p<0.05). Analysis of the gene co-expression network based on Pearson's correlation coefficients identified 10 up-regulated genes in the high-marbled group that formed a major cluster. Among these genes, the PPARG-FABP4 gene pair exhibited the strongest correlation in the network. Glycerol kinase was found to play a role in mediating activation of the differentially expressed genes. We categorized the 10 significantly differentially expressed genes into the corresponding downstream pathways and investigated the direct interactive relationships among these genes. We suggest that fatty acid oxidation is the major downstream pathway affecting IMF content. The PPARG/RXRA complex triggers activation of target genes involved in fatty acid oxidation resulting in increased triglyceride formation by ATP production. Our findings highlight candidate genes associated with the IMF content of the loin muscle of Korean cattle and provide insight into the biological mechanisms that determine adipose deposition within muscle.

• BMB Reports
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• v.41 no.4
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• pp.287-293
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• 2008

In a yeast two-hybrid screen, we identified the microtubule-destabilizing protein SCG10 as a potential effector protein of $BRI_3$. The association was verified using GST pull-down, Co-IP, and their perinuclear co-localization. The analysis of in vitro microtubule polymerization/depolymerization showed that the binding of $BRI_3$ to SCG10 effectively blocked the ability of SCG10 to induce microtubule disassembly, as determined by turbidimetric assays. In intact PC12 cells, $BRI_3$ exhibited the ability to stabilize the microtubule network and attenuate the microtubule-destabilizing activity of SCG10. Furthermore, co-expression of $BRI_3$ with SCG10 attenuated SCG10-mediated PC12 cell neurite outgrowth induced by NGF. These results identify a novel connection between a neuron-specific BRI protein and the cytoskeletal network, suggesting possible roles of BRI3 in the process of neuronal differentiation.

• Genomics & Informatics
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• v.1 no.1
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• pp.1-6
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• 2003

In conclusion, the seemingly fuzzy and disorganized data of biology with thousands of different layers ranging from molecule to the Internet have refused so far to be mapped precisely and predicted successfully by mathematicians, physicists or computer scientists. Genomics and bioinformatics are the fields that process such complex data. The insights on the nature of biological entities as complex interaction networks are opening a door toward a generalization of the representation of biological entities. The main challenge of genomics and bioinformatics now lies in 1) how to data mine the networks of the domains of bioinformatics, namely, the literature, metabolic pathways, and proteome and structures, in terms of interaction; and 2) how to generalize the networks in order to integrate the information into computable genomic data for computers regardless of the levels of layer. Once bioinformatists succeed to find a general principle on the way components interact each other to form any organic interaction network at genomic scale, true simulation and prediction of life in silico will be possible.

• Molecules and Cells
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• v.26 no.2
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• pp.206-211
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• 2008

HI0381 of Haemophilus influenzae was investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. HI0381 is a 153-residue peptidoglycan-associated outer membrane lipoprotein, and a part of the larger Tol/Pal network. Here, we report its backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments, and secondary structure predictions. About 97% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances covering 131 non-proline residues of the 134 residue, mature protein, were clarified by sequential and specific assignments. CSI and TALOS analyses revealed that HI0381 contains five ${\alpha}$-helices and five ${\beta}$-strands. To characterize the structure of HI0381, the effects of pH and salt concentration were investigated by CD. In addition, the structural changes occurring when HI0381 was in a membranous environment were investigated by comparing its HSQC spectra and CD data in buffer and in DPC micelles; the results showed that helix ${\alpha}4$ and strand ${\beta}4$ became aligned with the membrane. We conclude that the conformation of HI0381 is affected by the membrane environment, implying that its folded state is directly related to its function.

• IMMUNE NETWORK
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• v.4 no.1
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• pp.7-15
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• 2004

Background: The heat shock proteins (HSPs) play an important role in cellular protection mechanisms against physical or chemical stresses. In this study scFv antibodies specific for human HSP70.1 were isolated from a semi-synthetic human scFv library with the ultimate goal of developing anti-HSP70.1 intracellular antibody (intrabody) that may offer an attractive alternative to gene targeting to study the function of the protein in cells. Methods: A semi-synthetic human scFv display library ($5{\times}10^{8}$ size) was constructed using pCANTAB-5E vector and the selection of the library against bacterially expressed recombinant human HSP70.1 was attempted by panning. Results: Three positive clones specific for recombinant HSP70.1 were identified. All three clones used $V_{H}$ subgroup III. On the other hand, $V_{L}$ of two clones belonged to the kappa light chain subgroup I, but the other utilized $V_{k}$ subgroup IV Interestingly, these scFv molecules specifically reacted to the recombinant HSP70.1, yet failed to recognize native HSP70 induced in U937 human monocytic cells by heat treatment. Conclusion: Our results indicated that affinity selection of an scFv phage display library using recombinant antigens produced in E. coli might not guarantee the isolation of scFv antibody molecules specific for a native form of the antigen. Therefore, the source of target antigens needs to be chosen carefully in order to isolate biofunctional antibody molecules.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.611-614
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• 2010

Substituted imidazolidin-2-ones deduced as potential inhibitors of IleRS by docking simulations were synthesized from an aziridine-2-carboxaldehyde. Reductive amination of an aziridine-2-carboxaldehyde with dipeptides for the substituents at N1 and followed by aziridine-ring expansion with triphosgene afforded 4-chloromethylimidazolidin-2-ones whose chloride were further manipulated towards phenylurea, pyrimidin-2-yl-urea or benzenesulfonamide at C4.