• Pediatric Infection and Vaccine
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• v.7 no.1
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• pp.120-128
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• 2000

Purpose : Active immunization against hepatitis A with an inactivated vaccine reveals excellent immunogenicity, tolerability and protective efficacy. Inactivated hepatitis A vaccines have been selectively used since 1996 in Korea to prevent hepatitis A. This study was performed to assess the immunogenicity and reactogenicity after two doses of HM175 strain hepatitis A vaccine in healthy Korean children. Methods : 128 healthy children(M/F; 65/63) aged 1 to 15 years, who were seronegative for hepaitatis A, participated in this study. A alum-adsorbed vaccine containing 720 EL.U of antigen form HM175 hepatitis A strain per 0.5 mL dose was injected intramuscularly on the deltoid area. The second dose was given 6 months later, Anti-HAV antibodies were measured by ELISA before and 1 month after each vaccination to assess the immunogenicity. Any local and general adverse events were reported by patients parents with the prepared questionnaire after each vaccination. Results : 120 volunteers(M/F; 60/60) completed the whole series of the study. Seroconversion occurred in all cases after primary and booster vaccination. The mean anti-HAV antibody titer after primary vaccination was 389.2mIU/mL, and 3,609mIU/mL after booster vaccination. And levels of anti-HAV antibodies after booster immunization were significantly higher in female children. The most common local adverse event was soreness on the injection site, but it was mild and resolves within 3 days. Fever was not reported after booster vaccination. Conclusion : Based on these data, we conclude that the inactivated HM175 strain hepatitis A vaccine is highly immunogenic and tolerable in healthy Korean children.

• 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.15 no.2
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• pp.637-642
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• 2014

The pathogenesis of hepatocellular carcinoma (HCC) related to habitual betel quid (BQ) chewing is unclear. Risk of HCCis increased with adverse hepatic fibrosis. This study aimed to assess the impact of chronic viral hepatitis on adverse hepatic fibrosis in HCC related to BQ chewing. This hospital-based case-control study enrolled 200 pairs of age- and gender-matched patients with HCC and unrelated healthy controls. Serologic hepatitis B surface antigen (HBsAg), antibodies to hepatitis C virus (anti-HCV), ${\alpha}$-fetoprotein (AFP), and surrogate markers for significant hepatic fibrosis were measured. Information on substance-use habits was obtained with a questionnaire. By analysis of surrogate markers for hepatic fibrosis, the prevalence of significant hepatic fibrosis in patients chewing BQ was between 45.8% and 91.7%, whereas that for patients without BQ chewing was between 18.4% and 57.9%. The difference was significant (P <0.05 for each surrogate marker). Multivariate analysis indicated that cirrhosis with Child-Pugh C (odds ratio (OR) = 3.28; 95% confidence interval (CI), 1.29-8.37), thrombocytopenia (OR = 3.92, 95% CI, 1.77-8.68), AFP >400 mg/L (OR = 2.21, 95% CI, 1.05-4.66) and male gender (OR = 4.06, 95% CI, 1.29-12.77) were independent factors associated with habitual BQ chewing. In conclusion, adverse hepatic fibrosis and severe liver damage play important roles in the pathogenesis of BQ-related HCC, which could be aggravated by chronic hepatitis B and hepatitis C. BQ-cessation programs and prevention of chronic HBV/HCV infection are needed to prevent HCC related to BQ chewing.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.191-198
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• 1998

Vsrio vulnificus is an estuarine gram-negative human pathogen that affects people with chronic hepatitis, alcoholic cirrhosis, diabetes mellitus or other underlying diseases. V. vulnificus infection is mediated primarily by consumption of raw fish or by exposure of pre-existing wounds to seawater, causing permanent tissue damages or fatal septic shock. We have been developing a vaccine against V. vulnificus composed of whole cell Iysate of a V. vulnificus O-antigen serotype 4 strain. Oral administration of the V. vulnificus;oral vaccine;immunogenicity;protective efficacy vaccine elicited a high serum antibody response in rabbits. The induced antibodies were reactive not only to the homologous strain but also to heterologous O-antigen serotype strains, indicating cross-reactivities among serotypes. Western blot analysis revealed that the antibodies are mainly specific for outer membrane proteins (OMPs) and reacted equally well with OMPs purified from 9 O-antigen serotypes. The rabbit antisera showed opsonophagocytic killing activity against heterologous strains as well as the homologous strain. Passively transferred rabbit antisera into mice were protective against a lethal V. vulnificus infection. These data demonstrate that oral administration of the V. vulnificus vaccine induced a systemic antibody response which had a protective efficacy against V. vulnificus infections, suggesting that this vaccine preparation could be used to develop an oral vaccine against V. vulnificus.

• KSBB Journal
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• v.15 no.2
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• pp.214-218
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• 2000

A hepatitis B Surface Antigen(HBsAg)-screening kit using immunochromatographic assay(ICA) method was developed by e employing two kinds of antibodies. One is mouse monoclonal anti-HBs for tracer antibody and the other is goat p이yclonal a anti-HBs for capture antibody. This capture antibody was immobilized on the surface of nitroceliulose(NC) membrane and the t tracer antibody was conjugated with g미d particles. When serum sample was added to the sample well, the $\infty$njugates d deposited in a dry state on the surface of glass fiber filter were reconstituted and then combined with HBsAg in serum. In 5 5 min after adding, the assay result was visible through the window, that is, the complexes composed of HBsAg and the c conjugates appeared as maroon line on the lower part of the NC membrane. The detection limit of the ICA kit was 2 ng/ml w when being tested with the reference HBsAg.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.2
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• pp.132-136
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• 2020

Purpose: To evaluate the effect of gluten-free diet (GFD) on hepatitis B surface antibody (HBsAb) concentrations among previously immunized pediatric celiac disease (CD) subjects. Methods: We retrospectively evaluated pediatric CD subjects in serological remission who were previously immunized for hepatitis B virus as infants. The temporal relationship between HBsAb concentration, the amount of time on a GFD, and age were evaluated. Results: Overall, 373 CD subjects were analyzed: 156 with HBsAb sampled prior to GFD initiation and 217 after initiation of a GFD and in serological remission. Median age at HBsAb concentration measurement for those before and after GFD initiation was 5.3 years (interquartile range [IQR], 3.1-9.2 years) and 7.6 years (IQR, 5.4-10.9 years), respectively (p<0.001). There was no sex difference between the groups. The median time of HBsAb measurement was 2 months (IQR, 0-5.7 months) before and 12.8 months (IQR, 5.3-30.3 months) after initiation of GFD. The HBsAb concentration was low in 79 (50.6%) and 121 (55.7%) subjects before and after GFD initiation, respectively (p=0.350). Age was inversely associated with low HBsAb concentrations. Neither being on a GFD nor sex was associated with low HBsAb concentrations. Conclusion: Adherence to a GFD does not affect HBsAb concentration in children with CD. Age is inversely associated with HBsAb concentration.

• Clinical and Experimental Vaccine Research
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• v.12 no.1
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• pp.47-59
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• 2023

Purpose: The development and study of hepatitis C virus (HCV) vaccine candidates' individualized responses are of great importance. Here we report on an HCV DNA vaccine candidate based on selected envelope (E1/E2) epitopes. Besides, we assessed its expression and processing in human peripheral blood mononuclear cells (PBMCs) and in vivo cellular response in mice. Materials and Methods: HCV E1/E2 DNA construct (EC) was designed. The antigen expression of EC was assayed in PBMCs of five HCV-uninfected donors via a real-time quantitative polymerase chain reaction. Serum samples from 20 HCV antibody-positive patients were used to detect each individual PBMCs expressed antigens via enzyme-linked immunosorbent assay. Two groups, five Swiss albino mice each, were immunized with the EC or a control construct. The absolute count of lymph nodes' CD4⁺ and CD8⁺ T-lymphocytes was assessed. Results: Donors' PBMCs showed different levels of EC expression, ranging between 0.83-2.61-fold in four donors, while donor-3 showed 34.53-fold expression. The antigens expressed in PBMCs were significantly reactive to the 20 HCV antibody repertoire (all p=0.0001). All showed comparable reactivity except for donor-3 showing the lowest reactivity level. The absolute count % of the CD4⁺ T-cell significantly increased in four of the five EC-immunized mice compared to the control group (p=0.03). No significant difference in CD8⁺ T-cells % was observed (p=0.89). Conclusion: The inter-individual variation in antigen expression and processing dominance was evident, showing independence in individuals' antigen expression and reactivity levels to antibodies. The described vaccine candidate might result in a promising natural immune response with a possibility of CD4⁺ T-cell early priming.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7725-7730
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• 2014

Hepatocellular carcinoma (HCC) is the third most common cause for cancer death in the world, now being especially linked to chronic hepatitis C virus (HCV) infection. This case-control study consisting of 65 HCC patients and 82 patients with other malignant tumours as controls was conducted to determine the association of HCV markers with HCC. Serum of each participant was obtained for detection of HCV Ab and RNA by DNA enzyme immunoassay (DEIA). Twenty six per cent (26.0%) of HCC patients had positive anti-HCV which was significantly greater than the control group (p=0.001). HCC patients significantly have a risk of exposure to HCV infection almost 3 times than the control group (OR=2.87, 95% C.I=1.1-7). Anti-HCV seropositive rate was significantly (p=0.03) higher among old age HCC patients and increases with age. Males with HCC significantly showed to have more than 9 times risk of exposure to HCV infection (OR=9.375, 95 % CI=1.299-67.647) than females. HCV-RNA seropositive rate was (70.8%) significantly higher among HCC patients compared to (22.2%) the control group (p=0.019). The most prevalent genotype (as a single or mixed pattern of infection) was HCV-1b. This study detected a significantly higher HCV seropositive rate of antibodies and RNA in HCC patients.

• Pediatric Infection and Vaccine
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• v.12 no.2
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• pp.186-194
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• 2005

Purpose : Hepatitis A viral infections have been continued after re-emerging since mid 1990s in Korea. The incidence of this disease has been increased in young adults younger than 30 years of age since 2000. This study was performed to evaluate the prevalence of antibody to hepatitis A in Korea(two regions; Incheon and Changwon) in 2005, and was compared with the results of similar studies in mid 1990s. Methods : The study was conducted from January 2005 to June 2005, and consisted of 1,301 enrolled subjects, neonates to 50 years old, living in Incheon and Changwon in Korea. All sera were frozen and stored at $-70^{\circ}C$ until assayed. Anti-HAV IgG antibodies were measured by microparticle enzyme immunoassay(HAVAB, Abbott Lab., IL, USA). Results : The prevalence of anti-HAV IgG was 61.1% in infants younger than 1 year old, 30.5% in 1~5 years, 14.6% in 6~10 years, 1.7% in 11~15 years, 6.5% in 16~20 years, 36.6%in 21~30 years, 77.5% in 31~40 years, and 99.8% in 41~50 years. Statistical differences were not found between male and female, but there was statistical difference in 6~10 years old age group between the two areas. Conclusion : Our study indicate that the prevalence of antihepatitis A virus antibody has shifted from children to old adolescents and young adults. This result suggests that the risk of sudden outbreaks or increasing incidence of hepatitis A viral infections in young adults may be expected in our society. The preventive strategies of hepatitis A including vaccination should be prepared.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.630-634
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• 2006

Purpose : This study was conducted to assess the current(2003-2005) prevalence of anti-HBs and immunologic memory for Hepatitis B vaccine in children from the central area of Korea. Methods : Subjects were chosen from children and adolescents who received tests for hepatitis B surface antigen(HBsAg) and anti-HBs at Dankook University Hospital from March 2003 to May 2005. Among these, antibodies to hepatitis B core antigen(IgG anti-HBc) were checked. A single booster vaccination was performed on children whose anti-HBs titers were under 10 mIU/mL. One month after booster vaccination we rechecked the anti-HBs titer. Results : A total of 3,277 subjects were tested for HBsAg/anti-HBs, and 1,913(58.4 percent) of them were positive for anti-HBs. Of these, 29 subjects(0.9 percent) were positive for HBsAg. Positive results for anti-HBs by age were 78.6 percent for 6-12 months of age, 62.7 percent for 1-3 years of age, 51.9 percent for 4-6 years of age, 49.5 percent for 7-12 years of age, 63.4 percent for 13-15 years of age and 72.2 percent for 16-18 years of age. The 80 subjects who were tested negative for HBsAg/anti-HBs received a single booster vaccine, 71 subjects were tested positive for antibodies. IgG anti-HBc titer was checked for 169 of the subjects, 5 subjects were positive. Conclusion : In our study, a significant anamnestic response was observed in 88.8 percent of children. This is believed to be a result of the relatively long immunologic memory effect of the hepatitis B vaccination in children from the central area of Korea.