• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1336-1344
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• 2017

Hepatitis B virus (HBV) is a major cause of liver cirrhosis and hepatocellular carcinoma. With recent identification of HBV receptor, inhibition of virus entry has become a promising concept in the development of new antiviral drugs. To date, 10 HBV genotypes (A-J) have been defined. We previously generated two murine anti-preS1 monoclonal antibodies (mAbs), KR359 and KR127, that recognize amino acids (aa) 19-26 and 37-45, respectively, in the receptor binding site (aa 13-58, genotype C). Each mAb exhibited virus neutralizing activity in vitro, and a humanized version of KR127 effectively neutralized HBV infection in chimpanzees. In the present study, we constructed a humanized version (HzKR359-1) of KR359 whose antigen binding activity is 4.4-fold higher than that of KR359, as assessed by competitive ELISA, and produced recombinant preS1 antigens (aa 1-60) of different genotypes to investigate the binding capacities of HzKR359-1 and a humanized version (HzKR127-3.2) of KR127 to the 10 HBV genotypes. The results indicate that HzKR359-1 can bind to five genotypes (A, B, C, H, and J), and HzKR127-3.2 can also bind to five genotypes (A, C, D, G, and I). The combination of these two antibodies can bind to eight genotypes (A-D, G-J), and to genotype C additively. Considering that genotypes A-D are common, whereas genotypes E and F are occasionally represented in small patient population, the combination of these two antibodies might block the entry of most virus genotypes and thus broadly neutralize HBV infection.

• Journal of Preventive Medicine and Public Health
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• v.33 no.2
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• pp.226-230
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• 2000

Objectives : The purpose of this study was to suggest a proper method for the detection of heaptitis B surface antibody(anti-HBs) in a screening program for hepatitis B vaccination. Methods : Sensivitity, specificity and predictive values were compared between Immunochromatographic assay (ICA) and passive hemagglutination(PHA) in 978 subjects(565 males, 413 females, 19-78 years ranging in age, mean 46.5 years old). EIA was used as a standard method for the detection of HBsAb. Results : Sensitivity in the detection of anti-HBs of PHA and ICA was 88.7%, and 94.9%, specificity was 94.3% and 96.6%, negative predictive value was 96.5%, and 98.0%, and positive predictive value was 82.3%, and 91.3%,, respectively. False negative rate(11.3%) of PHA was higher than that(5.1%) of ICA. The higher the titer of anti-HBs in EIA was, the lower the false negative rate was. There was no false negative result in the cases with $101mIU/{\beta}c$ or more in EIA Conclusion : We suggest that ICA should be the choice of screening method in the detection of anti-HBs in Hepatitis B vaccination program.

• KSBB Journal
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• v.5 no.4
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• pp.365-371
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• 1990

To improve the growth of mouse hybridoma 2c3.1 secreting anti-Hepatitis B surface antigen monoclonal antibody (anti-HBsAg MAb), we had constructed an enriched medium and observed the effects of fetal bovine serum and serum-free supplements including human serum albumin, 'insulin and transferrin', and monoethanolamine. For further enhancement of growth, the concentrations of two major energy sources, glucose and glutamine, were strengthened with various ratios in the enriched medium. Maximum cell growth and monoclonal antibody production obtained in various ratios of glucose/glutamine with an inoculation concentration of 2$\times$105 cells/ml were 0.73$\times$106-4.62$\times$106 cells/ml and 65.1-422.6 $\mu\textrm{g}$/ml, respectively. Glutamine was round to be a major energy source and a limiting nutrient in comparison to glucose for 2c3.1 cell cultivation in enriched media with low serum.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.82-82
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• 1997

The hepatitis B virus(HBV) is a small, enveloped virus with a circular, double-stranded DNA genome. HBV causes active and chronic hepatitis worldwide, including Korea, and is considered to be a major factor for liver cirrhosis and hepatocellular carcinoma. In contrast to the wealth of knowledge on the gene structure and expressional regulation, immunological and pathological mechanisms for HBV-induced hepatocellular injury are not well known. In the present study, vaccinia virus which has been demonstrated to be a useful eukaryotic expression vector was used to clone the gene for HBV surface antigen, L(S+preS2+preS1). The recombinant vaccinia virus vector, pMJ-L, which contains L surface antigen gene of adr-type HBV was constructed, and subseouently used for making recombinant vaccinia virus VV-$\textrm{HBV}_{L}$. Expression of the HBV antigen was examined by immunofluorescent antibody (IFA) test using mouse monoclonal anti-hepatitis B surface antigen. HBsAg was detected in the recombinant virus indicating that the VV-$\textrm{HBV}_{L}$ expressed S antigen successfully. The HBV-Vaccinia Virus recombinant obtained in this study is currently being used for studying the immunological aspects of HBV infection.

• Journal of Preventive Medicine and Public Health
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• v.24 no.4 s.36
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• pp.465-472
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• 1991

This study was designed to estimate the prevalence of hepatitis C virus(HCV) infection in drug abusers. The subjects were 141 inpatients who had been admitted to a general hospital with the symptoms and signs of methamphetamine intoxication. Seroprevalence of antibody to the hepatitis C virus(anti-HCV) was 60.3%(85/141) and it was higher in the group with increased frequency and duration of drug abuse, but such a relationship was not found in the seroprevalence of hepatitis B surface antigen(HBsAg). These findings suggested the possibility of high prevalence of HCV infection in methamphetamine abusers, and the importance of repetitive percutaneous injection in the transmission of HCV infection.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.17-29
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• 1997

To estimate the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection and to determine associated risk factors, a population-based seroepidemiologic study was carried out. In 1993, a health examination survey of the population was carried out in rural area known to have a high incidence of liver cancer. The study population were those who volunteered to participate in a health survey over 10 years of age. Examinees were interviewed by specially trained staffs. Sera from 1,033 study subjects were tested for hepatitis B surface antigen (HBsAg) by .everse passive hemagglutinin (RPHA) estimation and for hepatitis C virus antibody (anti-HCV) by 2nd generation passive hemagglutinin (PHA) estimation. The age and sex standardized prevalence of HBsAg was 6.3% which was similar to national average, but that of anti-HCV was 5.1% which was 4 to 5 times higher than that of blood donors or other health examinees in Korea. In a multivariate analysis, transfusion history, surgical operative history, and acupuncture history were not associated with HBsAg positivity. In contrast, acupuncture history (adjusted odds ratio[OR]=2.2 : 95% Confidence interval[CI] 1.0-4.7) and surgical operative history(adjusted OR=2.0 : 95% CI 1.0-4.1) were associated with anti-HCV positivity. The present study suggest that there is an highly endemic area of HCV infection in Korea and probably this endemicity is associated with a parenteral source of HCV infection other than blood transfusion.

• Journal of Preventive Medicine and Public Health
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• v.25 no.2 s.38
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• pp.172-179
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• 1992

The author investigated the zinc concentrations in sera of 110 methamphetaimine abusers (male 87, female 23) and of 41 healthy official workers(male 29, female 12) using inductively coupled plasma emission spectrometer. The serum zinc concentrations were analysed according to hepatitis C virus antibody(Anti HCV), hepatitis B surface antigen(HBsAg) and alanine aminotransferase(ALT) value in both groups. The analytical results were obtained as follows 1. The mean zinc concentration of MAP abuser group($298.5{\pm]246.9{\mu}g/100ml$) was 2.5 times higher than that of control group($118.8{\pm}25.4{\mu}g/100ml$). 2. The distributions of zinc concentration in both groups were skewed pattern. 3. The zinc concentrations were higher in Anti HCV-positive group and abnormal ALT value group than Anti HCV-negative group and normal ALT value group. But HBs-Ag positive group had lower zinc concentration than HBs-Ag negative group. 4. The number of anti HCV-positive subjects was increased and the zinc concentrations were decreasd in proportion to the abusing duration of MAP.

• Korean Journal of Transplantation
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• v.32 no.4
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• pp.108-112
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• 2018

Antibody-mediated rejection (AMR) is a major complication after ABO-incompatible liver transplantation. According to the 2016 Banff Working Group on Liver Allograft Criteria for the diagnosis of acute AMR, a positive serum donor specific antibody (DSA) is needed. On the other hand, the clinical significance of the histological findings of AMR in the absence of DSA is unclear. This paper describes a 57-year-old man (blood type, O+) who suffered from hepatitis B virus cirrhosis with hepatocellular carcinoma. Pre-operative DSA and cross-matching were negative. After transplantation, despite the improvement of the liver function, acute AMR was observed in the protocol biopsy on postoperative day 7; the cluster of differentiation 19+ (CD19+) count was 0% and anti-ABO antibody titers were 1:2. This paper presents the allograft injury like AMR in the absence of DSA after ABOi living donor liver transplantation with low titers of anti-ABO antibody and depleted serum CD19+ B cells.

• BMB Reports
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• v.38 no.6
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• pp.683-689
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• 2005

Antibody to hepatitis B surface antigen (HBsAb) is the important serological marker of the hepatitis B virus (HBV) infection. Conventionally, the hepatitis B surface antigen (HBsAg) obtained from the plasma of HBV carriers is used as the diagnostic antigen for detection of HBsAb. This blood-origin antigen has some disadvantages involved in high cost, over-elaborate preparation, risk of infection, et al. In an attempt to explore the suitable recombinant HBsAg for the diagnostic purpose, the HBV S gene was expressed in Pichia pastoris and the product was applied for detection of HBsAb. Hepatitis B virus S gene was inserted into the yeast vector and the expressed product was analyzed by sodium dodecyl sulphate polyacrolamide gel electrophoresis (SDS-PAGE), immunoblot, electronic microscope and enzyme linked immunosorbent assay (ELISA). The preparations of synthesized S protein were applied to detect HBsAb by sandwich ELISA. The S gene encoding the 226 amino acid of HBsAg carrying ahexa-histidine tag at C terminus was successfully expressed in Pichia pastoris. The His-Tagged S protein in this strain was expressed at a level of about 14.5% of total cell protein. Immunoblot showed the recombinant HBsAg recognized by monoclonal HBsAb and there was no cross reaction between all proteins from the host and normal sera. HBsAb detection indicated that the sensitivity reached 10 mIu (micro international unit)/ml and the specificity was 100% with HBsAb standard of National Center for Clinical Laboratories. A total of 293 random sera were assayed using recombinant S protein and a commercial HBsAb ELISA kit (produced by blood-origin HBsAg), 35 HBsAb positive sera and 258 HBsAb negative sera were examined. The same results were obtained with two different reagents and there was no significant difference in the value of S/CO between the two reagents. The recombinant HBV S protein with good immunoreactivity and specificity was successfully expressed in Pichia pastoris. The reagent for HBsAb detection prepared by Pichia pastoris-derived S protein showed high sensitivity and specificity for detection of HBsAb standard. And a good correlation was obtained between the reagent produced by recombinant S protein and commercial kit produced by blood-origin HBsAg in random samples.

• BMB Reports
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• v.38 no.3
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• pp.294-299
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• 2005

In this report, we describe the high-yield secretory expression of the recombinant human anti-HBsAg Fab fragment from Pichia pastoris that was achieved by co-integration of the genes encoding the heavy and light chains (both under the control of alcohol oxidase promoter) into the genome of the yeast cells. The fed-batch fermentations were carried out in a 5 L scale. Both chains of the Fab were successfully expressed upon methanol induction. The absorbance ($OD_{600}$) of the broth can reach 350~500 at the end of fed-batch phase. After the induction, the expression level of the recombinant Fab (soluble) reached 420~458 mg/L. The recombinant Fab fragment was purified from the crude culture supernatant by ion exchange chromatography and the purity of the recombinant Fab fragment was over 95%. The affinity activities of the crude fermentation supernatant and the purified Fab were analyzed by indirect ELISA, which showed that the purified recombinant Fab fragment had high affinity activity with hepatitis B surface antigen.