• Journal of Life Science
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• v.13 no.4
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• pp.541-550
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• 2003

E2 glycoprotein of hepatitis C virus (HCV) comprises a surface of viral particle together with E1 glycoprotein, and is thought to be involved in the attachment of HCV viral particle to receptor (s) on the permissible cells including hepatocytes, B cells, T cells, and monocytes. We constructed a phage library expressing cellular proteins of hepatocytes on the phage surface, which turned out to be 8.8${\times}$$10^5$ cfu of diversity and carried inserts in 95% of library. We screened both cDNA phage library and 12-mer peptide library to identify the cellular proteins binding to E2 protein. Some intracellular proteins including tensin and membrane band 4.1 which are involved in signal transduction of survival and cytoskeleton organization, were selected from cDNA phage library through several rounds of panning and screening. On the contrary, membrane proteins such as CCR7, CKR-L2, and insulin-like growth factor-1 receptor were identified through screening of peptide library. Phages expressing peptides corresponding to those membrane proteins were bound to E2 protein specifically as determined by neutralization of binding assay. Since it is well known that HCV can infect T cells as well as hepatocytes, we examined to see if E2 protein can bind to CCR7, a member of C-protein coupled receptor family expressed on T cells, using CCR7 transfected tells. Human CCR7 cDNA was cloned into pcDNA3.1(-) vector and transfected into human embryonic kidney cell, 293T, and expressed on the surface of the cell as shown by flow cytometer. Binding assay of E2 protein using CCR7 transfected cells indicated that E2 protein bound to CCR7 by dose-dependent mode, giving rise to the possibility that CCR7 might be a putative cellular receptor for HCV.

• Journal of Veterinary Science
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• v.23 no.3
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• pp.33.1-33.10
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• 2022

Background: Endemic circulation of human-specific hepatitis E virus (HEV) genotypes 1 and 2 may occult the importance of sporadic zoonotic HEV transmissions in Africa. Increasing numbers of studies reporting anti-HEV antibodies in cattle and the discovery of infectious HEV in cow milk has raised public health concern, but cattle exposure has seldom been investigated in Africa. Objectives: This study aimed at investigating the role of cows in the epidemiology of HEV in Burkina Faso and farmers habits in terms of dairy product consumption as a prerequisite to estimate the risk of transmission to humans. Methods: Sera from 475 cattle and 192 pigs were screened for the presence of anti-HEV antibodies while HEV RNA in swine stools was detected by reverse transcription polymerase chain reaction. Data on mixed farming, dairy product consumption and selling habits were gathered through questionnaires. Results: The overall seroprevalence in cattle was 5.1% and herd seroprevalence reached 32.4% (11/34). Herd seropositivity was not associated with husbandry practice or presence of rabbits on the farms. However, herd seropositivity was associated with on-site presence of pigs, 80.7% of which had anti-HEV antibodies. The majority of farmers reported to preferentially consume raw milk based dairy products. Conclusions: Concomitant presence of pigs on cattle farms constitutes a risk factor for HEV exposure of cattle. However, the risk of HEV infections associated with raw cow dairy product consumption is currently considered as low.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.215-220
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• 2009

The prevalence of potentially xenozoonotic viruses in the reproductive tract of female pigs in Korea was investigated by polymerase chain reaction (PCR). These viruses include porcine endogenous retrovirus (PERV), porcine reproductive and respiratory syndrome virus (PRRSV), swine hepatitis E virus (SHEV), porcine lymphotropic herpesvirus (PLHV), and porcine circovirus type 2 (PCV-2). Histopathological examination and PCR analysis were conducted using the ovaries of 70 slaughtered pigs that were collected from 14 farms in Jeju. Histopathologically, infiltrations of mononuclear inflammatory cells around the thick-walled coiled vessels in the ovarian medulla were observed in 15 cases. Based on the PCR method, PERV, PLHV, PRRSV, SHEV, and PCV-2 were detected in 69 (98.6%), 35 (50%), 5 (7.1%), 4 (5.7%), and 1 sample (1.4%), respectively. These results suggest that PERV and PLHV are the major xenozoonotic viruses in the porcine ovary. This study should aid in the development of a monitoring protocol for potential xenozoonotic agents and in the production of germ-free pigs for xenotransplantation.

• BMB Reports
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• v.44 no.9
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• pp.607-612
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• 2011

Several investigators have shown that CpG-DNA has outstanding effects as a Th1-responsive adjuvant and that its potent adjuvant effects are enhanced by encapsulation with a liposome of proper composition. In this study, we showed that encapsulation with phosphatidyl-${\beta}$-oleoyl-${\gamma}$-palmitoyl ethanolamine (DOPE): cholesterol hemisuccinate (CHEMS) complex enhances the immunostimulatory activity of CpG DNA and the binding of CpG-DNA to TLR9. We also examined involvement of myeloid differentiation protein (MyD88) and NF-${\kappa}B$ activation in liposome-encapsulated CpG-DNA-induced IL-8 promoter activation. In this manuscript, the natural phosphodiester bond CpG-DNA encapsulated by DOPE : CHEMS complex is designated as Lipoplex(O). Importantly, we successfully screened B cell epitopes of envelope protein (E protein) of hepatitis C virus (HCV-E) and attachment glycoprotein G of human respiratory syncytial virus (HRSV-G) by immunization with complexes of several peptides and Lipoplex(O) without carriers. Therefore, Lipoplex(O) is potentially applicable as a universal adjuvant for peptide-based epitope screening and antibody production.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.27 no.2
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• pp.104-112
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• 2024

Purpose: Immunosuppressive therapy is frequently administered to patients with inflammatory bowel disease (IBD), which may make them more susceptible to infections like hepatitis B. Methods: A cross-sectional study was conducted on patients aged 5-18 years diagnosed with IBD who visited a gastroenterology clinic along with controls who were the same age as the patients with IBD and were healthy overall. A logistic regression analysis using the independent variables of age, sex, race, disease phenotype, surgery, and medications and the dependent variable of adequate hepatitis B surface antibody (HBsAb) titers (>10 mIU/mL) was performed on quantitative serum HBsAb titers. Results: The study enrolled 62 patients, including 37 males and 25 females. Crohn's disease, ulcerative colitis, and indeterminate colitis were diagnosed in 16, 22, and 24 patients, respectively. Thirty-nine patients were taking corticosteroids at the time of the study, 42 were taking immunomodulators, and four were taking biologics. Compared to 44.7% of the control group, 9.3% of the patients had protective titers. Only 12 out of 62 patients had HBsAb titers greater than 10 million IU/mL. None of the patients who received biologics or corticosteroids and 3.2% of those who received immunomodulators were found to be seroimmuned. Conclusion: The younger patients had the highest titers. Patient-specific factors that may impact these low titers include the length of the patient's illness and the use of immunosuppressants.

• IMMUNE NETWORK
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• v.4 no.1
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• pp.16-22
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• 2004

Background: To develop a novel treatment strategy for hepatitis B virus infection, a major cause of liver chirosis and cancer, we aimed to make human monoclonal antibodies inhibiting RNase H activity of P protein playing in important role in HBV replication. In this regard, phage display technology was employed and demonstrated as an efficient cloning method for human monoclonal antibody. So this study analysed the usability of human monoclonal antibody as protein based gene therapy. Methods: RNase H of HBV was expressed as fusion protein with maltose binding protein and purified with amylose resin column. Single chain Fv (scFv) phage antibody library was constructed by PCR cloning using total RNAs of PBMC from 50 healthy volunteers. Binders to RNase H were selected with BIAcore 2000 from the constructed library, and purified as soluble antibody fragment. The affinity and sequences of selected antibody fragments were analyzed with BIAcore and ABI automatic sequencer, respectively. And finally RNase H activity inhibiting assay was carried out. Results: Recombinant RNase H expressed in E. coli exhibited an proper enzyme activity. Naive library of $4.46{\times}10^9cfu$ was screened by BIAcore 2000. Two clones, RN41 and RN56, showed affinity of $4.5{\times}10^{-7}M$ and $1.9{\times}10^{-7}M$, respectively. But RNase H inhibiting activity of RN41 was higher than that of RN56. Conclusion: We cloned human monoclonal antibodies inhibiting RNase H activity of P protein of HBV. These antibodies can be expected to be a good candidate for protein-based antiviral therapy by preventing a replication of HBV if they can be expressed intracellularly in HBV-infected hepatocytes.

• Journal of agricultural medicine and community health
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• v.31 no.3
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• pp.245-253
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• 2006

Objectives: Since 1983, vaccination for Hepatitis B virus has been recommended for all neonates in Korea. The objectives of this study was to assess the changing trend of the positive rate of HBsAg and anti-HBs in university students in one province. Methods: The study population consisted of one university students who taken physical exam in 2004, which included 8,527 students (3,391 males and 5,136 females). Serum HBsAg and anti-HBs were detected by immunochromatography method. Results: The positivities of HBsAg and anti-HBs were 2.7% and 61.1%. The positivity of HBsAg was significantly higher in males(p< .05), while that of anti-HBs was significantly higher in females(p< .05). There was some differences of HBsAg positivities among age groups. But there was no correlation between age and the positivities. There was some differences of anti-HBs positivities among age groups. But there was no correlation between age and the positivities. Conclusion: The positivity of HBsAg has significantly decreased and that of anti-HBs has increased with years. It was suggested that the changes of positivity were caused by nationwide hepatitis B vaccination program.

• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.353-356
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• 1994

Chimeric kappa chain and gamma chain cDNA clones (pCKS2 and pCHS2) of a monoclonal antibody specific for pre-S2 surface antigen of human hepatitis-B virus were ligated into Xbal site of plant expression vector pBKS-1. Plasmid DNA containing each of the chimeric gene were then mobilized from E, coli to Agrobacterium tumefaciens strain LBA4404. The chimeric antibody genes were then introduced into tobacco by Ti plasmid-mediated transformation. The putative Transformants were selected on medium containing kamaycin sulfate. Shoots that formed on shoot induction medium were analyzed by Western blot analysis for the expression of kappa-chain or gamma-chain genes. The Western blot analyses clearly showed that the introduced genes were stably expressed in transgenic plants.

• Clinical and Experimental Pediatrics
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• v.63 no.2
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• pp.52-55
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• 2020

Background: Immunomodulatory properties of interferon (IFN) have been documented. It may induce autoimmune diseases such as autoimmune thyroiditis with hypo- or hyperthyroidism. In addition, it may impair thyroid hormone synthesis through affecting iodide organification in thyroid gland. Purpose: The aim of this study was to describe thyroid function tests disturbances in children with chronic hepatitis C (CHC) receiving pegylated interferon-alpha (PEG IFN-α) plus ribavirin. Methods: Fifty children with CHC virus infection who received combined pegylated interferon-alpha with ribavirin were selected. Other 50 apparently healthy children of matched age and sex (considered as control group) were selected. All children (100) were subject to liver function tests, virological studies, and follow-up of thyroid function test during and after the treatment course. Results: Our study showed that 28% of children received combined PEG IFN-α plus ribavirin showed subclinical hypothyroidism. After 24 weeks treatment with combined therapy of IFN plus ribavirin, the mean level of thyroid stimulating hormone (TSH) was 3.23±88 mU/mL, while TSH was 1.16±0.77 mU/mL before starting treatment. On the other hand, mean TSH was 1.09±0.92 mU/mL in normal control group. Conclusion: This study revealed an association between subclinical thyroid dysfunction and treatment with IFN-alpha and ribavirin in children. Further studies on larger number of patients and longer follow-up duration are recommended for further confirmation.

• The Journal of Internal Korean Medicine
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• v.42 no.4
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• pp.455-474
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• 2021

The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) that applied herbal medicine to treat viral hepatitis B and C in order to determine the therapeutic efficacy of herbal medicine. EMBASE, Pubmed, NDSL, KMBASE, KISS, KISTI, Koreamed, Koreantk, and Oasis databases were searched to identify RCTs. The selected studies were assessed by the Cochrane group's risk of bias tool. A total of 15 RCTs were selected, and the hepatitis B virus (HBV) DNA reduction was significantly higher in patients treated with herbal medicine combined with Western medicine than in patients treated with herbal medicine. Herbal medicine combined with Western medicine was also superior to Western medicine alone in achieving hepatitis B e-antigen (HBeAg) and alanine aminotransferase [ALT] reduction. Only herbal medicine alone was not superior to Western medicine treatments in achieving HBV DNA, HBeAg, and ALT reduction.