• IMMUNE NETWORK
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• v.3 no.2
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• pp.126-135
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• 2003

Background: One of the important factors in the prognosis of chronic hepatitis B patient is the degree of replication of hepatitis B virus (HBV). It has been known that HBV DNA polymerase plays the essential role in the replication of HBV. HBV DNA polymerase is composed of four domains, TP (Terminal protein), spacer, RT (Reverse transcriptase) and RNaseH. Among these domains, tyrosine, the $65^{th}$ residue of TP is an important residue in protein-priming reaction that initiates reverse transcription. If monoclonal antibody that recognizes around tyrosine residue were selected, it could be applied to further study of HBV replication. Methods: To produce TP-specific scFv (single-chain Fv) by phage display, mice were immunized using synthetic TP-peptide contains $57{\sim}80^{th}$ amino acid residues of TP domain. After isolation of mRNA of heavy-variable region ($V_H$) and light-chain variable region ($V_L$) from the spleen of the immunized mouse, DNA of $V_H$ and $V_L$ were obtained by RT-PCR and joined by a DNA linker encoding peptide (Gly4Ser)3 as a scFv DNA fragments. ScFv DNA fragments were cloned into a phagemid vector. scFv was expressed in E.coli TG1 as a fusion protein with E tag and phage gIII. To select the scFv that has specific affinity to TP-peptide from the phage-antibody library, we used two cycles of panning and colony lift assay. Results: The TP-peptide-specific scFv was isolated by selection process using TP-peptide as an antigen. Selected scFv had 30 kDa of protein size and its nucleotide sequences were analyzed. Indirect- and competitive-ELISA revealed that the selected scFv specifically recognized both TP-peptide and the HBV DNA polymerase. Conclusion: The scFv that recognizes the TP domain of the HBV DNA polymerase was isolated by phage display.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.356-365
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• 2012

There have been growing concerns among people about food safety due to insufficient information on foodborne pathogens. In this study, we developed a risk priority of 15 foodborne pathogens. For the priority determination we collected risk profile criteria information from CODEX Alimentarius Commission and developed countries. The basis for criteria we selected from information of surveillance were frequency and severity of disease, frequency of consumption and probability of cross-contamination. We also considered foodborne pathogens which have been managed in developed countries though those pathogens are not currently managed appropriately in Korea. Priorities were divided into three groups following these consideration. The first priority group includes Norovirus, pathogenic E. coli, Salmonella spp, Clostridium botulinum and Listeria monocytogenes. The second priority group includes Vibrio parahaemolyticus, Stapylococcus aureus, Campylobacter jejuni and Bacillus cereus, and the third priority group includes Clostridium perfringens, Yersinia enterocolitica, Shigella spp, Cronobacter sakazakii and Hepatitis A virus. Our results could be applied to prevent foodborne illness from fresh produce.

• Parasites, Hosts and Diseases
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• v.56 no.1
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• pp.61-70
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• 2018

We developed a Rapid Diagnostic Test (RDT) kit for detecting IgG/IgM antibodies against Zika virus (ZIKV) using monoclonal antibodies to the envelope (E) and non-structural protein 1 (NS1) of ZIKV. These proteins were produced using baculovirus expression vector with Sf9 cells. Monoclonal antibodies J2G7 to NS1 and J5E1 to E protein were selected and conjugated with colloidal gold to produce the Zika IgG/IgM RDT kit (Zika RDT). Comparisons with ELISA, plaque reduction neutralization test (PRNT), and PCR were done to investigate the analytical sensitivity of Zika RDT, which resulted in 100% identical results. Sensitivity and specificity of Zika RDT in a field test was determined using positive and negative samples from Brazil and Korea. The diagnostic accuracy of Zika RDT was fairly high; sensitivity and specificity for IgG was 99.0 and 99.3%, respectively, while for IgM it was 96.7 and 98.7%, respectively. Cross reaction with dengue virus was evaluated using anti-Dengue Mixed Titer Performance Panel (PVD201), in which the Zika RDT showed cross-reactions with DENV in 16.7% and 5.6% in IgG and IgM, respectively. Cross reactions were not observed with West Nile, yellow fever, and hepatitis C virus infected sera. Zika RDT kit is very simple to use, rapid to assay, and very sensitive, and highly specific. Therefore, it would serve as a choice of method for point-of-care diagnosis and large scale surveys of ZIKV infection under clinical or field conditions worldwide in endemic areas.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1349-1353
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• 2012

Increasing evidence has revealed that thy-1 was a potential stem cell marker of liver cancer, but no data have been shown on how thy-1 regulates the pathophysiology of liver cancer, such as proliferation, apoptosis, invasion and migration. We previously demonstrated that thy-1 was expressed in about 1% of hepg2 cells, thy-1+hepg2 cells, but not thy-1-, demonstrating high tumorigenesis on inoculation $0.5{\times}10^5$ cells per BACA/LA mouse after 2 months. In the present study, our results showed that higher expression of thy-1 occurs in 72% (36/50 cases) of neoplastic hepatic tissues as compared to 40% (20/50 cases) of control tissues, and the expression of thy-1 is higher in poorly differentiated liver tumors than in the well-differentiated ones. In addition, thy-1 expression was detected in 85% of blood samples from liver cancer patients, but none in normal subjects or patients with cirrhosis or hepatitis. There was a significant negative correlation between thy-1expression and E-cadherin expression (a marker of invasion and migraton), but not between thy-1 expression and AFP expression in all the liver cancer and blood samples. We further investigated the relationship between thy-1 and E-cadherin in liver cancer hepg2 cell line which was transfected with pReceiver-M29/thy-1 eukaryotic expression vector followed by aspirin treatment. Lower expression of E-cadherin but higher expressions of thy-1 were detected in hepg2 cells transfected with pReceiver-M29/thy-1. Taken together, our study suggested that thy-1 probably regulates liver cancer invasion and migration.

• Proceedings of the Korean Society of Veterinary Pathology Conference
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• 2002.11a
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• pp.146-146
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• 2002

Hepatic disease has been noted and reported for involvement various detrimental factors. Among many detrimental injury factors, alcohol has been noted for hepatitis, fatty liver, fibrosis, and hepatic cirrhosis. The purpose of this study is to develop animal model for hepatic fibrosis in pig with ethanol, and to search new anti-fibrogenic agent. Twelve male Landrace pigs were divided into 3 groups of 4 animals each. Group 1, 2 and 3 were fed with ceramic water only, ceramic water + liquid diet containing 20％ ethanol and normal tap water + containing 20％ ethanol for 12 weeks, respectively. At week 12, all pigs were immediately sacrificed for collection each tissue and blood. Serologically, serum ALT and AST levels were significantly reversed in group 2, comparing to group 3. They were normal range in pigs of group 1. Microscopically, macrovesicular lipid droplets and moderate necrosis were evident in the tap water + ethanol fed group 3. However, ceramic water intake group 1 showed normal. Moreover, in group 3, little fatty changes and mild necrosis were observed. Collagen fibers were detected in the spaces of surrounding periportal and interlobular areas in the group 3 of tap water + ethanol, but collagen synthesis and its thickness of fibrotic septa connecting portal tracts was markedly reduced in the group 2 of ceramic water + ethanol. In immunohistochemistry, myofibroblasts were detected in the ethanol and tap water treated group 3. No or a few myofibroblasts were observed in groups 1 and 2. CYP 2E1 was rarely detected in group 1 fed ceramic water. However, group 2 showed slightly activation of CYP 2E1 in the area of pericentral, while CYP 2E1 was significantly activated in group 3 fed tap and ethanol. Taken together above, alcohol fibrosis model in pig was established. Furthermore, ceramic water had an inhibitory and protecting ability for alcohol-induced hepatic damages.

• Korean Journal of Veterinary Service
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• v.26 no.4
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• pp.345-359
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• 2003

A number of toxicants have been incriminated as a causing hepatic disease. Among many detrimental injury, alcohol has been noted for hepatitis, fatty liver, fibrosis, and hepatic cirrhosis. The purpose of this study was to develop animal model for hepatic fibrosis in pigs fed ethanol, and to search for a new anti-fibrogenic agent via this model. Twelve male Landrace pigs were divided into 3 groups of 4 animals each. Group 1, 2 and 3 were fed with active ceramic water only, ceramic water + liquid diet containing 15% ethanol and normal tap water + liquid diet containing 15% ethanol for 12 weeks, respectively. At week 12, all pigs were immediately sacrificed for collection each tissue and blood. Serologically, serum ALT and AST levels were significantly reversed in group 2, as compared to group 3. They were normal range in pigs of group 1. Microscopically, macrovesicular lipid droplets and moderate hepatocellular necrosis were evident in the tap water + ethanol fed group 3. However, the active ceramic water treated group 1 showed normal architecture. Moreover, in group 2, mild fatty changes and necrosis were observed in hepatocytes. Collagen fibers were increased in spaces surrounding periportal and interlobular connective tissues in the group 3 of tap water + ethanol, but collagen synthesis and its thickness of fibrotic septa connecting portal tracts were markedly reduced in the group 2 of ceramic water + ethanol. Myofibroblasts were detected mainly in the interlobular connective tissues of pig liver of group 3 treated ethanol and tap water. Few to no myofibroblasts were observed in groups 1 and 2. CYP2E1 was not or rarely detected in group 1 fed ceramic water. However, group 2 showed slightly activation of CYP2E1 in the area of pericentral vein, while CYP2E1 was significantly activated in group 3 fed tap water and ethanol. Based on the above data, we believe that we have developed a unique alcohol induced fibrosis model in pig, which will be useful in developing anti-fibrotic agents and drugs. Furthermore, the active ceramic water used in our study had an inhibitory and may be protective against ethanol induced hepatic toxicity and fibrosis.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.2
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• pp.86-93
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• 2007

Chronic inflammation has been known to have a close relationship with several diseases including periodontitis, colitis, hepatitis and arthritis. Recently anti-inflammatory agents have been developed from marine natural resources. In this study, Ecklonia cava (EC) was found to have anti-inflammatory effect. Ethanolic extract of EC belonging to brown algae exhibited an excellent inhibitory effect on the production of inflammatory mediators such as tumor necrosis factor-${\alpha}$, interleukin-$1{\beta}$, interleukin-6 and prostaglandin $E_2$ by RA W264.7 cells. Furthermore, in reporter gene assay and western blot analysis, EC extract exerted anti-inflammatory effect via inactivation of NF-${\kappa}B$ transcription factor that regulates the expression of these inflammatory mediators in macrophages. In addition, EC extract inhibited the activity of matrix metalloproteinase that play an important role in chronic inflammation. These results suggest that EC extract may provide a pharmaceutical potential in inhibiting chronic inflammation.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.130-136
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• 2007

Artemisia capillaris THUNB is a perennial herb that belongs to the family Compositae spp and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. In this study, antimicrobial effects of Artemisia capillaris extracts on the food poisoning bacteria were investigated for further clinical application, which is an alternative for the use of antibiotics and their unexpected resistance. Artemisia capillaris extract using ethyl acetate showed the highest antimicrobial effects on S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus. The chloroform extract showed strong effects on all kinds of bacteria; whereas ethanol and methanol extracts showed weaker effects. Finally, ether and water extracts showed the weakest effects under the same conditions. The minimum inhibitory concentration (MIC) of ethyl acetate extract was 1 mg/mL for E. coli O157 : H7 and L. monocytogenes, and 2 mg/mL for S. enteritidis and S. aureus. The inhibitory effects on all the bacteria continued for 12 hours after incubation using 20 mg/mL and 30 mg/mL of ethyl acetate extract. The inhibitory effects continued maximally for 72 hours. The results of these studies indicate Artemisia capillaris extract exhibited excellent antimicrobial and inhibitory effects on the food poisoning pathogenic bacteria; S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.155-167
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• 1997

The identification of serum HBV DNA is very important for the assessment of the disease activity in persistent infection, for the evaluation of the infectivity of an individuals blood. The dot blot, however, has limited sensitivity and sometimes inconsistent with other serological markers and clinical settings. Using the most important recent advance in molecular biology, the polymerase chain reaction(PCR), specific DNA sequences can be amplified more than a million-fold in a few hours and with this technique the detection of the extreme low level of DNA is possible. This study was to determine sensitivity of the PCR for the detection of serum HBV DNA in comparison with dot blot analysis and to investigate the serum HBV DNA status and clinical significance of PCR in patients with chronic HBsAg positive liver disease. The subjects of this study were 17 patients with asymptomatic HBsAg carriers(9 HBeAg positive patients, 8 anti-HBe positive patients), 91 chronic hepatitis B(50 HBeAg positive patients, 41 anti-HBe positive patients), 57 liver cirrhosis(21 HBeAg positive patients, 36 anti-HBe positive patients), 27 hepatocellular carcinoma(10 HBeAg positive patients, 17 anti-HBe positive patients). The results were summerized as following; The detection rates of HBV DNA by dot blot, PCR were 58.9%, 72.2% in HBeAg positive patients, 34.3%, 53.9% in anti-HBe positive patients. The detection rates of HBV DNA by PCR in HBeAg negative patients were 25.0% in asymptomatic HBsAg carriers, 61.0% in chronic hepatitis B, 52.8% in liver cirrhosis, 52.9% in hepatocellular carcinoma. The positive rate for HBV DNA is a significant difference between HBeAg positive and negative asymptomatic HBsAg carriers, but not significantly difference in other groups. In conclusions, this study confirmed that the PCR is much more sensitive than the dot blot analysis in detecting the HBV DNA in the sera of patients with chronic liver disease. The presence of HBV DNA in the serum was detected by PCR with higher sensitivity and it suggested that active viral replication is still going on in most patients with chronic HBsAg positive liver disease irrespective of HBeAg/anti-HBe status, and PCR may be used as a prognostic factor in asymptomatic HBsAg carriers.

• Journal of Veterinary Clinics
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• v.23 no.1
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• pp.72-76
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• 2006

A 1-year-old, female English cocker spaniel (ECS) dog was presented with 3-month history of vomiting and retaking of the vomitus, and chronic weight loss. The client had noticed mild abdominal distension 10 days before. The dog was diagnosed as chronic hepatitis with hepatic cirrhosis based on complete blood count (CBC), serum chemistry profiles, radiography, ascites assessment, bile acid evaluation, and liver biopsy through exploratory laparotomy and necropsy. CBC and serum chemistry profiles revealed mild anemia, slightly elevated hepatic enzymes (ALT and AST), increased creatinine kinase (CK), hyperammonemia, and hypoproteinemia with hypoalbuminemia. Ascites was transudate according to analysis of components. Bile acid assessment (fasting; $174.4{\mu}mol/L$ and postprandial; $198.4{\mu}mol/L$) showed strongly suspected hepatic insufficiency. On radiological findings, ascites was evident. Atrophied liver (especially left side lobes) and distended mesenteric vasculatures were observed by exploratory laparotomy. Histopathological examination of marginal lesion of left lateral lobe of liver by biopsy revealed the necrosis of hepatic cells, dilation of sinusoids, infiltration of neutrophils in sinusoids, and vacuolation of hepatic cytoplasm. The patient had been managed with careful low protein diet and specific supportive therapy (ursodeoxycholic acid, prednisolone, vitamine E, and interferon). Vomiting and ascites disappeared with medical management. The dog was monitored periodically by CBC, serum chemistry and radiographic examination. The dog survived more 18 months with medical therapy. After spontaneous death, necropsy and histopathologic examination were performed.