• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.6 no.1
• /
• pp.32-38
• /
• 2003

Purpose: Hepatic allografts from donors with hepatitis B core antibody have been demonstrated to transmit hepatitis B virus (HBV) infection to recipients after liver transplantation (LT). The efficacy of hepatitis B immune globulin (HBIg) to prevent de novo hepatitis B was investigated by comparing active immunization in the early phase to HBIg monotherapy in the late phase of pediatric liver transplants at Samsung Medical Center. Methods: Among pediatric liver transplants, from May, 1996 to June, 2002, 15 recipients who were hepatitis B surface antigen (HBsAg) (-) received an allograft from a donor with hepatitis B core antibody (HBcAb) (+). Except two who died from unrelated causes, eleven of 13 recipients were HBsAb (+), and 2 were naive (HBsAb(-), HBcAb(-)). All patients were vaccinated for HBV before LT. In the early phase (January, 1997~November, 1997, 3 patients), HBsAb (+) recipients received booster vaccination after LT. In the late phase (December, 1997~, 10 patients), all recipients were given booster vaccination and received HBIg therapy in order to maintain HBsAb titer greater than 200 IU/L. Lamivudine was given in one case because of severe side effect of HBIg. We retrospectively analyzed the effect of the preventive therapy for de novo hepatitis B through medical records. Results: De novo hepatitis B developed in three of 13 recipients (23.1%). All of 3 patients who received active immunization in the early phase became HBsAg (+) at 7~19 months after transplantation. One of them was naive before LT and the other two were HBsAb (+). All of 10 recipients who were given HBIg in the late phase remained HBsAg (-) at 7~55 months' follow-up. Conclusion: Passive immunization with HBIg was effective for prevention of de novo hepatitis B in HBsAg (-) recipients of hepatic allografts from HBcAb (+) donors.

• Pediatric Infection and Vaccine
• /
• v.6 no.2
• /
• pp.253-260
• /
• 1999

Purpose : The purpose of this study is to make and use monoclonal Ab which reacts with CMV major immediate early(${\alpha}$) protein(p72). Methods : Normal human fibroblast(Foreskin derived) was cultured in Eagle's minimal essential medium(MEM) containing 10% cowfetus serum and mouse chondroblast was cultured in P3X63 Ag8.653(ATCC. Maryland USA) to maintain $5{\times}10^5/ml$ cell counts. CMV(KJHJ90) from congenital CMV infected infant's urine was multiplied and used for Ab making. CMV Ag was injected 4 times, 1 week interval into the peritoneal space of 6~8 weeks old mice. And then lymphocyles and fibroblasts taken from spleen were obtained and conjugated. After the conjugated cell cultured, we chose the cell that had high Ab titer using indirect immunofluerescent method. Results : Among the 28 monoclonal antibodies obtained LPC12 and LPC23 reacted highly with nucleus of AD169 infected cell. Purified AD169 after SDS-PAGE, molecular weight of Ag, which reacted with purified monoclonal Ab, was obtained using Western blotting. Monoclonal Ab of LPC12 and LPC23 clone reacted most highly with 72 kd Ag. Conclusion : LPC12 and LPC23 clonal Ab with AD 169(P63-27) is useful on early diagnosis of CMV infection.

• Journal of the Korea Convergence Society
• /
• v.11 no.1
• /
• pp.77-82
• /
• 2020

In order to analyze the positive rate of hepatitis B surface antibody by age before and after hepatitis B vaccination, 13,855 serum specimens who were referred for the hepatitis B surface antibody test at the General Hospital of Jeju Hospital were examined by CMIA method. The positive rate of HBs Ab was 5,176 (37.36%). The positive rate according to gender was 40.13% for female and 34.77% for male. The age group with the highest HBs Ab average was in their 40's (399.86 mIU/mL), while the lowest age group was in the 90's (211.50 mIU/mL). It is remarkable that the age group with the highest HBs Ab positive rate is in the 30's, and that teenagers (age group of 10-20 years) had the lowest positive rate. Especially 15, 18, 19 years old was statistically significant. Consideration should be given to determining the titer of vaccination and to clarify the timing of vaccination.

• BMB Reports
• /
• v.33 no.1
• /
• pp.92-95
• /
• 2000

The HIV-1 p24(202-221) sequence ETINNEEEWDRVHPV HAGP contains a B-cell epitope with the earliest immune response and the highest antibody titer against anti-mouse sera obtained by immunization with p24 antigens. A novel mouse monoclonal antibody (mAb) was generated against the immunodominant B-cell epitope of the HIV-1 p24 capsid protein, p24(202-221). BALB/c mice were immunized with the four branched multiple antigenic peptide (MAP) containing the HIV-1p24(202-221) sequence, and antibody-secreting hybridoma were produced by fusion of mouse splenocytes with P3X63Ag8.653, mouse myeloma cells. One clone which produced the antigen-specific mAb named KI-24 (Isotype IgG1, light chain: ${\kappa}$) was identified. mAb KI-24 was highly specific for both the p24(202-221) and p24 proteins when analyzed by ELISA and Western blotting. Since p24(202-221) also contains a cytotoxic T-lymphocyte epitope, this specfic peptide epitope and the monoclonal antibody with specific reactivity against the p24 protein and p24(202-221) can be used in peptide vaccine development and p24 antigen detection from HIV patients.

• Toxicological Research
• /
• v.17
• /
• pp.197-199
• /
• 2001

Enhancement of antigen-specific IgE is a hallmark of allergic hyperresponsiveness, therefore it is necessary to adopt or develop a highly sensitive and specific assay for determination of allergen-specific IgE levels in vivo. In this presentation, we introduce an ELISA (enzyme linked immunosorbent assay) system developed to measure the levels of chicken egg ovalbumin (OVA)-specific IgE in serum. The ELISA method uses a commercially available purified rat anti-mouse IgE as a capture Ab and biotinylated OVA as a detection reagent. Avidin-peroxidase with its substrate is used for color development resulting in optical density measurement at 405 nm. The ELISA system produces a highly sensitive dose-response relation-ship between optical density levels and the dilution titer of the OVA-IgE standard serum but no cross-reaction with unrelated IgE or IgG. It is believed that the system is an Efficient tool to delineate an adjuvant effect of environmental pollutants on development of asthmatic and atopic responses.

• Journal of Yeungnam Medical Science
• /
• v.10 no.2
• /
• pp.306-312
• /
• 1993

To evaluate the meaning of anti-HCV detection in patients treated with IVIG, serum levels of aspartate aminotranstferase(AST), alanine aminotransterase(ALT), HCV Ab titer were measured after treatment with IVIG in 36 patients diagnised of Kawasaki disease or neonatal sepsis. Also polymerase chain reaction (PCR) for the detection of HCV was done in 8 patients with persistent HCV Ab positivity at 3 months after IVIG treatment. The results were as follows 1) HCV Ab was positive in all 36 patients at 1 week after IVIG treatment, but in only 8 cases it was positive at 3 months after IVIG treatment. 2) AST, ALT were elevated in 9 cases at 1 week after IVIG treatment, but they were normalized in all cases at 3 months after IVIG treatment. 3) PCR for the detection of HCV was done in 8 patients with persistent HCV Ab positivity at 3 months after IVIG treatment, but HCV was not isolated in any cases. These results suggested that detection of anti-HCV was merely transitory phenominon of HCV Ab transmission, did not show any evidence of HCV infection due to HCV transmission.

• Journal of Veterinary Clinics
• /
• v.25 no.4
• /
• pp.227-230
• /
• 2008

To determine the distribution of feline blood types and then to estimate the risk of neonatal isoerythrolysis (NI) in non-pedigree cats, we typed blood of 482 cats of both genders and various breeds (336 domestic shorthair cat and 146 pedigree) from August 2005 through July 2007. Blood samples from Seoul and Kangwon province were typed within 5 days after collection by the simple tube method. High-titer anti-A antiserum and anti-B reagent, prepared with Triticum vulgaris lectin, were used to determine type A and type B blood, respectively. The majority of cats were type A (n = 465, 96.5%) and only 3.5% (n = 17) were type B. No type AB blood were detected. Blood type distributions among the non-pedigree and pedigree cats were similar: for non-pedigree cats, 96.4% were type A and 3.6% were type B, whereas for pedigree cats, 96.6% were type A and 3.4% were type B. All type B cats had a very strong agglutination reaction to anti-A antiserum: 8 sample for 3+ and 9 for 4+. Assuming 19% of estimated frequency for the type-B allele in domestic cats, the calculated proportion of random mating from this population at risk for developing NI was 3.4%. Based on this finding, it is strongly recommended that blood typing be performed prior to any blood transfusion or breeding to minimize blood type incompatibilities. Further comprehensive studies on the titer of naturally occurring antibodies in cat populations in Korea and the prevalence of possible NI in practice are clearly required.

• Parasites, Hosts and Diseases
• /
• v.39 no.1
• /
• pp.67-76
• /
• 2001

This experiment was focused on the characterization of anti- Toxoplasma monoclonal antibodies (mAbs) and the effect of mAbs on the parasite invasion of mouse peritoneal macrophages. Twenty eight mAbs including M110, M556, R7A6 and M62l were characterized by Ab titer, immunoglobulin isotyping and western blot pattern. Antibody titer (optical density) of 4 mAbs. Ml 10. M556. R7A6 and M62l. were 0.53,0.67, 0.45 and 0.39 (normal mouse serum; 0.19) with the same IgGl isotypes shown by Enzyme-linked immunosorbent assay (ELISA). Western blot analysis showed that Ml 10. M556. R7A6 and M62l reacted with the 33 kDa (p30),31 kDa (p28),43 kDa and 36 kDa protein. Immuno-gold labelling of mAbs M110, M556, R7A6 and M621 reacted with the surface membrane, dense granules and parasitophorous vacuolar membrane (PVM) , rhoptries and cytoplasm of tachyzoite, respectively. For in vitro assay, preincubation of tachyzoties with four mAbs, Ml 10, M556, R7A6 and M62l resulted in the decrease of the number of infected macrophages (p < 0.05) and the suppression of parasite multiplication at 18 h post-infection. Four monoclonal antibodies including Ml 10 (SAGI) were found to have an important role in the inhibition of macrophage invasion and T. gondii multiplication in vitro, and these mAbs may be suitable for vaccine candidates, diagnostic kit and for chemotherapy.

• Clinical and Molecular Hepatology
• /
• v.24 no.4
• /
• pp.374-383
• /
• 2018

Background/Aims: There have been numerous efforts to reduce mother-to-child transmission (MTCT) of hepatitis B virus (HBV) with antiviral agents during pregnancy. However, there are limited data regarding the outcomes of pregnant women after delivery. This study was performed to evaluate the efficacy of antiviral agents in preventing MTCT of HBV and maternal long-term outcomes. Methods: The HBV-infected pregnant women treated with antiviral agents to prevent MTCT were retrospectively reviewed. Forty-one pregnant women who received telbivudine or tenofovir during late pregnancy (28-34 week) were analyzed. Hepatitis B virus surface antibody (HBsAb) positivity was tested in 43 infants after 7 months of birth. Eleven mothers were followed >1 year after delivery. Results: The mean HBV DNA titer before antiviral therapy was 8.67 (6.60-9.49) log copies/mL, and the median age at delivery was 32 years (range, 22-40). Eleven patients were treated with tenofovir and 30 with telbivudine. The median duration was 57 days (range, 23-100), and the median HBV DNA titer at birth was 5.06 log copies/mL (range, 2.06-6.50). Antiviral treatments were associated with significant HBV DNA reduction (P<0.001). Among 43 infants (two cases of twins), HBsAb was not detected in two, subsequently confirmed to have HBV infection. Biochemical flare was observed in two of 11 mothers followed >12 months, and an antiviral agent was administered. Conclusions: Antiviral treatment during late pregnancy effectively reduced MTCT. Long-term follow-up should be required in such cases. In addition, given that maternal biochemical flare occurred in 18% of mothers, re-administration of antiviral agents might be required.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.9
• /
• pp.1327-1338
• /
• 2013

The humanized anti-hepatocyte growth factor (HGF) monoclonal antibody (mAb) YYB-101 is a promising therapeutic candidate for treating various cancers. In this study, we developed a bioprocess for large-scale production of YYB-101 and evaluated its therapeutic potential for tumor treatment using a xenograft mouse model. By screening diverse chemically defined basal media formulations and by assessing the effects of various feed supplements and feeding schedules on cell growth and antibody production, we established an optimal medium and feeding method to produce 757 mg/l of YYB-101 in flask cultures, representing a 7.5-fold increase in titer compared with that obtained under non-optimized conditions. The optimal dissolved oxygen concentration for antibody production was 70% $pO_2$. A pH shift from 7.2 to 7.0, rather than controlled pH of either 7.0 or 7.2, resulted in productivity improvement in 5 L and 200 L bioreactors, yielding 737 and 830 mg/ml of YYB-101, respectively. The YYB-101 mAb highly purified by affinity chromatography using a Protein A column and two-step ion exchange chromatography effectively neutralized HGF in a cell-based assay and showed potent tumor suppression activity in a mouse xenograft model established with human glioblastoma cells.