• Journal of Microbiology and Biotechnology
• /
• v.21 no.1
• /
• pp.100-108
• /
• 2011

A method for the rapid detection and quantification of Newcastle disease virus (NDV) produced in an animal cell culture-based production system was developed to enhance the speed of the NDV vaccine manufacturing process. A SYBR Green I-based real-time RT-PCR was designed with a conventional, inexpensive RT-PCR kit targeting the F gene of the NDV LaSota strain. The method developed in this study was validated for specificity, accuracy, precision, linearity, limit of detection (LOD), limit of quantification (LOQ), and robustness. The validation results satisfied the predetermined acceptance criteria. The validated method was used to quantify virus samples produced in an animal cell culture-based production system. The method was able to quantify the NDV samples from mid- or late-production phases, but not effective on samples from the early-production phase. For comparison with other quantifiable methods, immunoblotting, plaque assay, and tissue culture infectious dose 50 ($TCID_{50}$) assay were also performed with the NDV samples. The results demonstrated that the real-time RT-PCR method is suitable for the rapid quantification of virus particles produced in an animal cell-culture-based production system irrespective of viral infectivity.

• The Korean Journal of Physiology and Pharmacology
• /
• v.17 no.6
• /
• pp.525-530
• /
• 2013

Multidrug resistance 3 (MDR3) is expressed on the canalicular membrane of the hepatocytes and plays an important role in protecting the liver from bile acids. Altered ABCB4 gene expression can lead to a rare hepatic disease, low phospholipid-associated cholelithiasis (LPAC). In this study, we characterized 3 ABCB4 mutations in LPAC patients using various in vitro assay systems. We first measured the ability of each mutant to transport paclitaxel and then the mechanisms by which these mutations might change MDR3 transport activity were determined using immunoblotting, cell surface protein biotinylation, and immunofluorescence. Through a membrane vesicular transport assay, we observed that the uptake of paclitaxel was significantly reduced in membrane vesicles expressing 2 ABCB4 mutations, F165I and S320F. Both mutants showed significantly decreased total and cell surface MDR3 expression. These data suggest two missense mutations of ABCB4 may alter function of MDR3 and ultimately can be determined as LPAC-causing mutations.

• The Korean Journal of Physiology and Pharmacology
• /
• v.21 no.4
• /
• pp.397-405
• /
• 2017

MDL-12330A is a widely used adenylyl cyclase (AC) inhibitor that blocks AC/cAMP signaling. In this study, we demonstrated a novel antitumor activity of this drug in gastric carcinoma (GC) cell lines. In these GC cells, MDL-12330A reduced cell viability and induced cell death in a concentration-dependent manner. At a moderate concentration (${\sim}20{\mu}M$), MDL-12330A mainly induced apoptotic death whereas at concentrations greater than $20{\mu}M$, it increased non-apoptotic cell death. The induction of apoptosis was at least partially regulated by CHOP-mediated DR5 upregulation, as detected by immunoblotting and gene interference assays. More importantly, low concentrations of MDL-12330A effectively enhanced recombinant human tumor necrosis factor (TNF)-related apoptosis-inducing ligand (rhTRAIL)-induced apoptosis and clonogenicity in these gastric cancer cells. This study demonstrates a possible role of MDL-12330A as a potential sensitizer to TRAIL, and suggests a novel therapeutic strategy targeting gastric cancer cells.

• The Korean Journal of Physiology and Pharmacology
• /
• v.21 no.4
• /
• pp.449-456
• /
• 2017

Beauvericin (BEA), a cyclic hexadepsipeptide produced by the fungus Beauveria bassiana, is known to have anti-cancer, anti-inflammatory, and anti-microbial actions. However, how BEA suppresses macrophage-induced inflammatory responses has not been fully elucidated. In this study, we explored the anti-inflammatory properties of BEA and the underlying molecular mechanisms using lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells. Levels of nitric oxide (NO), mRNA levels of transcription factors and the inflammatory genes inducible NO synthase (iNOS) and interleukin (IL)-1, and protein levels of activated intracellular signaling molecules were determined by Griess assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter gene assay, and immunoblotting analysis. BEA dose-dependently blocked the production of NO in LPS-treated RAW264.7 cells without inducing cell cytotoxicity. BEA also prevented LPS-triggered morphological changes. This compound significantly inhibited nuclear translocation of the $NF-{\kappa}B$ subunits p65 and p50. Luciferase reporter gene assays demonstrated that BEA suppresses MyD88-dependent NF-${\kappa}B$ activation. By analyzing upstream signaling events for $NF-{\kappa}B$ activation and overexpressing Src and Syk, these two enzymes were revealed to be targets of BEA. Together, these results suggest that BEA suppresses $NF-{\kappa}B$-dependent inflammatory responses by suppressing both Src and Syk.

• Molecules and Cells
• /
• v.38 no.6
• /
• pp.518-527
• /
• 2015

Controlled release of medications remains the most convenient way to deliver drugs. In this study, we precipitated gold nanoparticles with quercetin. We loaded gold-quercetin into poly(DL-lactide-co-glycolide) nanoparticles (NQ) and tested the biological activity of NQ on HepG2 hepatocarcinoma cells to acquire the sustained release property. We determined by circular dichroism spectroscopy that NQ effectively caused conformational changes in DNA and modulated different proteins related to epigenetic modifications and c ell cycle control. The mitochondrial membrane potential (MMP), reactive oxygen species (ROS), cell cycle, apoptosis, DNA damage, and caspase 3 activity were analyzed by flow cytometry, and the expression profiles of different anti- and pro-apoptotic as well as epigenetic signals were studied by immunoblotting. A cytotoxicity assay indicated that NQ preferentially killed cancer cells, compared to normal cells. NQ interacted with HepG2 cell DNA and reduced histone deacetylases to control cell proliferation and arrest the cell cycle at the sub-G stage. Activities of cell cycle-related proteins, such as $p21^{WAF}$, cdk1, and pAkt, were modulated. NQ induced apoptosis in HepG2 cells by activating p53-ROS crosstalk and induces epigenetic modifications leading to inhibited proliferation and cell cycle arrest.

• Development and Reproduction
• /
• v.12 no.2
• /
• pp.183-194
• /
• 2008

A variety of stem cells has been emerging as therapeutic cells that can replace organ transplantation in human liver diseases. The present study focused on whether human eyelid adipose-derived stem cells (HAD) might differentiate into functional hepatocyte-like cells in vitro. HAD were isolated from human eyelid adipose tissue. Effect of dimethyl sulfoxide (DMSO), fibroblast growth factor (FGF)-2 and FGF-4 on the hepatic differentiation of HAD have been examined in vitro. Immunocytochemical analysis and PAS staining showed that HAD cultured in both DMSO and FGF-4 exhibited the most intense staining than HAD of the other experimental groups. These HAD expressed numerous hepatocyte-related genes. Immunoblotting analyses showed that HAD cultured in the presence of DMSO and FGF-4 secreted higher amount of human albumin than HAD cultured in other conditions. Urea analysis also demonstrated that these HAD produced higher amount of urea than any other groups of HAD. In conclusion, combined treatment of DMSO and FGF-4 could effectively induce the functional differentiation of HAD into hepatocyte-like cells.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.82-83
• /
• 2003

Plants have evolved differently from animals having mobile activities. Thus, plants should have developed unique defense mechanisms against biotic/abiotic stresses to which plants are differently exposed, according to seasons. Most organisms have an conserved signaling network using mitogen-activated protein kinase (MAPK) cascade(s). The phenomenon implied that they are functionally very important in all organisms. In fact, they constitute one of the major components of signaling pathways involved in regulating a wide range of cellular activities from growth and development to cell death. Recently, complete MAPK cascade was first characterized in Arabidopsis from the receptor kinase (FLS2) through fellowing MEKKI -MKK4/MKK5-MPK3/MPK6-WRKY22/MRKY29 pathway. Whereas, MAPK cascade signaling pathway in monocot plant including rice (0ryza sativa L.), the most important of all food crops and an established monocot plant research model, MAPKinase kinase kinases (MAPKKK) of rice are the first upstream component of the MAPK cascade, but MAPKKK has been first identified and characterized in our lab and designated as, OsEDRl based on its homology with the Arabidopsis EDRI. The Arabidopsis EDRl was regarded as a negative regulator of defense response and the role of rice OsEDRl was analyzed. Transcriptional regulation of OsEDRl was detected under various stresses and immunoblotting analysis is going on to detect the level of OsEDRl protein in the mutants showing unique phenotype. We also introduced the constitutively active and the dominant negative forms of the OsEDRl for characterizing biological function.

• Journal of Life Science
• /
• v.15 no.5 s.72
• /
• pp.779-782
• /
• 2005

Cell-free expression is a powerful tool for rapid protein analysis, enabling an efficient identification of gene without cumbersome procedure of transformation and cell culture. Epoxide hydrolase (EH) gene of Rhodotorula glutinis was simply amplified by PCR, and the resultant gene was expressed in vitro using a coupled Transcription/translation system. The cell-free expressed EH protein mixture exhibited the enantioselective hydrolysis activity toward (R)-styrene oxide, representing that cell-free protein synthesis system can be used for the rapid expression of an enantioselective enzyme for an efficient identification of the chiral activity.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.10 no.5
• /
• pp.444-450
• /
• 2005

Epidermal growth factor (EGF) activates many intracellular effector molecules, which subsequently influence the expression levels of many genes involved in cell growth, apoptosis and signal transduction, etc. In this study, the early response of gene expressions due to EGF treatment was monitored using oligonucleotide DNA microarrays in rat schwannoma cell lines. An immunoblotting experiment showed the successful activation of EGF receptors and an effector protein, STAT5, due to EGF treatment. The microarray study showed that 35 genes were significantly induced and 2 were repressed within 60 min after the treatment. The list of induced genes included early growth response 1, suppressor of cytokine signaling 3, c-fos, interferon regulatory factor 1 and early growth response 2, etc. According to the microarray data, six of these were induced by more than 10-fold, and showed at least two different induction patterns, indicating complicated regulatory mechanisms in the EGF signal transduction.

• Macromolecular Research
• /
• v.11 no.6
• /
• pp.451-457
• /
• 2003

Anion-substituted poly(vinyl alcohol) (PVA) membranes, carboxymethylated PVA (C-PVA), and sulfonated PVA (S-PVA) were prepared and the effects of these substitutions on the plasma protein adsorption were studied by one- and two-dimensional gel electrophoresis and immunoblotting. When Cuprophane was used as a negative control, the amount of total proteins bound to samples decreased in the order Cuprophane > PVA > C-PVA > S-PVA, which we attribute to the effects of the surface characteristics of the samples, such as their surface tensions and electrostatic properties, on the adsorption of proteins to the surfaces of the materials. The results revealed that albumin was the most abundant protein in all the samples. The proportion of adsorbed fibrinogen to S-PVA exceeded those of PVA and C-PVA, whereas S-PVA exhibited the lowest IgG adsorption affinity among the samples we studied.