• KSBB Journal
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• v.21 no.4
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• pp.260-266
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• 2006

Methanol induction conditions with various additives for the enhanced production of recombinant hepatitis B surface antigen(HBsAg) were investigated in Pichia pastoris, which can utilize methanol as a carbon source and produce recombinant proteins under the control of strong, tightly-regulated alcohol oxidase(AOX) promoter. The presence of non-methanol carbon sources such as glycerol and glucose fully repressed the expression of AOX promoter. Various additives were tested to improve the production of recombinant protein and it was found that sorbitol could be a good carbon source during methanol induction period. An optimized concentration of amino acid mixture enhanced the production of HBsAg significantly. Pluronic F-68, a non-ionic surfactant, also improved the production of HBsAg without inhibiting cell growth. Addition of oleic acid at 0.01%(v/v) during the induction period showed positive effect on the production of HBsAg. Finally, 1.2%(v/v) of trace salts enhanced the production of HBsAg 1.9 times compared to that of control culture.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.10 no.2
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• pp.166-172
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• 2007

Purpose: It has recently been reported that de novo HBV infection following liver transplantation is caused by grafts from HBcAb positive donors, and this phenomenon has been observed in one third of the liver transplant patients in our center. Therefore, we investigated the presence of HBV virus DNA in liver tissues obtained from HBcAb positive donors to determine the mechanism by which de novo HBV infection occurs. Methods: This study was conducted on 6 patients that were HBsAg negative, HBsAb positive, and HBcAb positive who were donors for liver transplantation between November 1997 and November 1998 at Asan Medical Center. We isolated DNA from a portion of liver biopsy tissues that were obtained during the operation, and then identified the surface and core region of HBV DNA using nested PCR. In addition, four children who received liver grafts from these donors were monitored to determine if they became afflicted with non-HBV related diseases while receiving prophylaxis consisting of short-term HBIG treatment and long-term treatment with an antiviral agent. Results: The surface antigen region was identified in all 6 donors and the core antigen region was observed in 4 of the 6 donors. However, no episodes of de novo HBV infection with prophylaxis were observed. Conclusion: The results of this study support the results of previous studies, which indicated that HBV infection may be the main cause of de novo HBV infection in patients that receive HBsAb positive and HBcAb positive donor grafts.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3419-3424
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• 2013

Diverse immunoassays including a chemiluminescent immunoassay (CIA) are used to detect hepatitis B surface antigen (HBsAg) and antibody (anti-HBs). Recently, an increasing number of institutions have been utilizing an immunochromatography assay (ICA), which is easy to use. In this study, We evaluated ICA kits for the rapid detection of HBsAg and anti-HBs by comparing them with a CIA. A total of 120 serum hospital samples, were collected for the whole month, were assayed using ICA kit. The Concordance rate, sensitivity, specificity, positive predictive value and negative predictive value of the ICA for HBsAg based on CIA results were 97%, 97%, 100%, 100%, and 96.8%, respectively. The diagnostic performances of the ICA for Anti-HBs were 90%, 90%, 93.3%, 93.1%, and 90.3%, respectively. The ICA kit failed to detect HBsAg and anti-HBs in low reactive samples. The ICA kits for the rapid detection of HBsAg might be recommended for interpreted with caution and dual analysis in the clinical laboratory.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.238-243
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• 1999

This study was undertaken to test for anti-hepatitis B virus (HBV) activity of the aqueous extracts prepared from 9 medicinal plants of Korea (Cornus officinalis, Caesalpinia sappan, Rubus coreanus, Lycium chinense, Artemisia capillaris, Isatis tinctoria, Phyllanthus urinaria, Lysimachia christinae, Lonicera japonica). Aqueous extracts were tested for cytotoxicity and assayed for inhibition of HBV replication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium f HepG2 2.2.15 cells. The extract from Rubus coreanus, Artemisia capillaris, Phyllanthus urinaria decreased the levels of extracellular HBV virion DNA at concentrations ranging from 128 to $256\;{\mu}g/ml$ and inhibited the production fo HBsAg dose-dependently without showing cytotoxicity. Our findings suggest that these three hebal medicinal plants may have potential to develop as specific anti-HBV drugs in the future.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7675-7679
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• 2013

Background: A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocellular carcinoma (HCC) patients with or without positive HBsAg. Materials and Methods: Paraffin embedded liver tissues were obtained from 124 HCC patients who underwent liver resection and liver biopsy in King Chulalongkorn Memorial Hospital. Restriction fragment length polymorphism (RFLP) was utilized to detect the R249S mutation. Positive results were confirmed by direct sequencing. Results: Sixty four (52%) patients were positive for HBsAg and 18 (15%) were anti-HCV positive. 12 specimens tested positive by RFLP. Ten HCC patients (8.1%) were confirmed to be R249S positive by Sanger sequencing (AGG to AGT). Out of these 10, six were HBsAg positive, and out of the remaining 4, two were anti-HCV positive. The R249S prevalence among HCC patients with positive HBsAg was 9.4% compared to 6.7% for HBsAg negative samples. Patients with the R249S mutation were younger ($55{\pm}10$ vs $60{\pm}13$ year-old) and tended to have a more advanced Edmonson-Steiner grade of HCC, although differences did not reach statistical significance. Conclusions: Our study shows moderate prevalence of aflatoxin B1-related p53 mutation (R249S) in HCC with or without HBsAg. HBsAg positive status was not associated with R249S prevalence.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.338-343
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• 2003

Various factors, such as the adsorption pH, adjuvant dose, and adjuvant age, which affect the adsorption degree and immunogenicity of an antigen, were investigated. In addition, the effect of pH, antigen content, and adjuvant content on immunogenicity was also studied through animal experiments. Within the ranges studied, a low pH for adsorption, freshly preformed gel, and low pH formulation for the combined DTwP-HepB vaccine were preferrable for the adsorption of the antigens. In addition, a higher DT content was found to have a positive effect on the HBsAg immunogenicity in the combined vaccine. Accordingly, considering the factors affecting the adsorption rate and immunogenicity of the antigens, a novel DTwP-HepB vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $24\;\mu\textrm{g}$ of HBsAg, $24\;\mu\textrm{g}\;Al/ml\;of \;Al(OH)_3\;gel,\;776\;\mu\textrm{g}\; Al/ml\;of\;AIPO_4\;gel$, and pH 7.1) was developed, whose immunogenicity was comparable to the case of administrating, separately and simultaneously, a combined DTwP vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis, $300\;\mu\textrm{g}\;Al/ml\;of\; AIPO_4\;gel$, and pH 7.1) and mono HepB vaccine [$Hepavax^{\circledR},\;24\;\mu\textrm{g}/ml$ of HBsAg and $500\;\mu\textrm{g}\;Al/ml\;of\;Al(OH)_3\;gel$], which satisfies the potency criteria of the K-FDA for a combined DTwP vaccine and mono HepB vaccine.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.247-250
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• 2002

Pichia pastoris, a methylotrophic yeast widely used for the production of heterologous proteins, was used to produce Hepatitis B surface antigen (HBsAg) under the control of the strong, tightly-regulated alcohol oxidase promoter. It is highly induced during the growth on methanol, but the presence of non-methanol carbon sources such as glycerol and glucose repressed fully the expression of alcohol oxidase. In this study, glycerol and sorbitol feedings for the expression of the recombinant HBsAg were compared to examine the potential of sorbitol as a less repressive carbon source in fed-batch fermentation. The sorbitol feeding enhanced the production yield by 12% compared to that in glycerol feeding, although the cell concentration was lower.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6227-6231
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• 2013

In the past, hepatitis B virus (HBV) infection was endemic in the general Korean population. The association of HBV infection with the occurrence of liver cancer has been well demonstrated in several epidemiologic studies. While the mortality rates of liver cancer in Korea have decreased steadily over the last decade, the presence of hepatitis B surface antigen (HBsAg) in mothers remains high at 3-4%, and 25.5% of these HBsAg positive mothers are positive for hepatitis B e antigen (HBeAg). HBV infection caused almost a quarter of hepatocellular carcinoma (HCC) cases and one-third of deaths from HCC. These aspects of HBV infection prompted the Korean government to create a vaccination program against HBV in the early 1980s. In 1995, the Communicable Disease Prevention Act (CDPA) was reformed, and the government increased the number of HBV vaccines in the National Immunization Program (NIP), driving the vaccination rate up to 95%. In 2000, the National Health Insurance Act (NHIA) was enacted, which provided increased resources for the prevention of perinatal HBV infection. Then in 2002, the Korean government, in conjunction with the Korean Medical Association (KMA), launched an HBV perinatal transmission prevention program. The prevalence of HBsAg in children had been high (4-5%) in the early 1980s, but had dropped to below 1% in 1995, and finally reached 0.2% in 2006 after the NIP had been implemented. After the success of the NIP, Korea finally obtained its first certification of achievement from the Western Pacific Regional Office of the World Health Organization (WPRO-WHO) for reaching its goal for HBV control. An age-period-cohort analysis showed a significant reduction in the liver cancer mortality rate in children and adolescents after the NIP had been implemented. In addition to its vaccination efforts, Korea launched the National Cancer Screening Program (NCSP) for 5 leading sites of cancer, including the liver, in 1999. As a consequence of this program, the 5-year liver cancer survival rate increased from 13.2% (1996-2000) to 23.3% (2003-2008). The development of both the primary and secondary prevention for liver cancer including HBV immunization and cancer screening has been of critical importance.

• Perspectives in Nursing Science
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• v.7 no.1
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• pp.50-54
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• 2010

The studies of M. Colombo (1989) and W. Lange (1992) showed that 30~40% of people became chronic after suffering from hepatitis B virus (HBV) and C virus (HCV) infection, and about 50% of the chronic cases transformed into primary liver cancer. There have been few studies done in Mongolia on hepatitis infection among health professionals, particularly in nurses. In a study done by Chimedsuren (8), the study showed that 19.4% of people with identified surface hepatitis B antigen (HBsAg) and antibodies to hepatitis C virus and 8% of people with the identified nucleotide of RNA for the hepatitis C virus (polymerase chain reaction) had an acute form of hepatitis C. Studies on the hepatitis virus genome damaging effect on liver cells showed that genotype 8 (A, B, C, D, E, F, G, TTV) had the most damaging effect on liver cells (Hahn and Faeka, 2007). Several studies have shown a relationship between hepatitis B virus infection and a lack of compliance regarding safety regulations and rules by medical personnel. Results of a study from the Maternal and Child Health Research Center showed that tests done to detect hepatitis B virus antigen and antibodies to C virus did not reveal anything. Both antigen and antibodies in 69% cases did not show, and separately, B virus and antibodies to hepatitis C virus were identified in 13% and 9%, respectively. Results of the tests taken from health personnel in Shastin Central Hospital showed that in 76% of the cases, the B virus antigen with C virus antibodies was not identified. In 8% of the cases, the B virus antigen was present on its own. The combination of B the virus antigen and C virus antibodies were present in 8% of nurses and doctors, respectively. 82% of the cases had negative results for the detection of a combination of B virus antigen and C virus antibodies taken from health personnel from the State Central Clinical Hospital whereas the B virus antigen and C virus antibodies by themselves were present in 7% and 14% of the cases, respectively. Combined cases of the B virus antigen and C virus antibodies were identified in 4% of the personnel. Results of the tests taken from the health personnel in the Hospital of the Ministry of Justice and Internal Affairs showed that in 79% of the cases, the B virus antigen with C virus antibodies were not identified. Separately, the B virus and antibodies to hepatitis C virus were identified in 8% and 13% of the cases, respectively.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.80.2-80.2
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• 2003

The nucleoside analogue, L-FMAUS was synthesized from L-FMAU which has been shown to have significant antiviral acitivity against hepatitis B virus (HBV). The anti-HBV activity and toxicity of the L-FMAUS were examined by a cell culture system using a hepatitis B virus (HBV) producing cell line, HepG2 2.2.15. L-FMAUS was assayed for the inhibition of HBV multiplication by measurement of HBV DNA and surface antigen (HBsAg) levels in the extracellular medium of HepG2 2.2.15 cells after an 8-day treatment. (omitted)