• The Journal of the Korean Society for Microbiology
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• v.21 no.1
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• pp.151-161
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• 1986

In order to develop sensitive and sepcific assay methods for E. coli heat labile enterotoxin(LT) hybridoma cell lines secreting LT specific monoclonal antibody were obtained. LT was purified from cell lysate of E. coli O15H11. The steps included disruption of bacteria by French pressure, DEAE Sephacel ion exchange chromatography, Sephadex G200 gel filtration, and second DEAE Sephacel ion exchange chromatography, successively. Spleen cells from Balb/c mice immunized with the purified LT and $HGPRT^{(-)}$ plasmacytomas, $P3{\times}63Ag8.V653$ were mixed and fused by 50% (w/v) PEG. Hybrid cells were grown in 308 wells out of 360 wells, and 13 wells out of them secreted antibodies reacting to LT. Among these hybridoma cell 1G8-1D1 cell line was selected since it had produced high-titered monoclonal antibody continuously. By using culture supernatant and ascites from 1G8-1D1 cells the monoclonal antibody was characterized, and an assay system for detecting enterotoxigenic E. coli was established by double sandwich enzyme-linked immunosorbent assay (ELISA). The following results were obtained. 1. Antibody titers of culture supernatant and ascites from 1G8-1D1 hybridoma cells were 512, and 102, 400, respectively by GM1-ELISA and its immunoglobulin class was IgM. 2. The maximum absorption ratio of 1G8-1D1 cell culture supernatant to LT was 90% at $300\;{\mu}g/ml$ of LT concentration. LT concentration shown at 50% absorption ratio was $103.45{\mu}g$ and the absorption ratio was decreased with tile reduction of LT concentration. This result suggests that monoclonal antibody from 1G8-1D1 hybridoma cell bound with LT specifically. 3. The reactivities of 1G8-1D1 cell culture supernatant to LT and V. cholerae enterotoxin(CT) were 0.886 and 0.142(O.D. at 492nm) measured by the GM1-ELISA, indicating 1G8-1D1 monoclonal antibody reacted specifically with LT but not with CT. 4. The addition of 0.1ml of ascites to 0.6mg and 0.12mg of LT decreased the vascular permeability factor to 41% and 44% respectively, but it did not completely neutralize LT. 5. By double sandwich ELISA using monoclonal antibody, as little as 75ng of the purified LT per ml could be detected. 6. The results by assay of detecting LT in culture supernatants of 14 wild strains E. coli isolated from diarrhea patients by the double sandwich ELISA were almost the same level as those by reverse passive latex agglutination.

• Parasites, Hosts and Diseases
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• v.38 no.1
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• pp.29-31
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• 2000

A toxoplasmic uveitis case was reported on the focus of impairment of pathological findings and serological antibody titers after chemotherapy. A chief complaint of a 60-year-old male was a decreased and blurred vision in his right eye for 2 weeks after experiencing tremendous stress and fatigue. A steroid therapy for 3 weeks was not effective and the retinal lesion became necrotic. Anti-Toxoplasma gondii antibody titer was checked to be a strong positive by both ELISA and indirect latex agglutination assay (lLA). He was treated with Fansidar F for 8 weeks. His vision improved as the necrotic lesion healed by scarring, but the antibody titers still remained very high without any signs of negative conversion. It is suggested to be a recurrent case of the past asymptomatic infection by presumed immune suppression caused by excessive stress.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.339-344
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• 1999

Immunological method has been applied in biochemical genetic analysis of seed storage proteins. We developed and characterized anti-gliadin polyclonal antibody (AGPab) specific to gliadin fractions whose quality and quantity were known to be associated with wheat end-use quality. Reactions of anti-gliadin polyclonal antibody (AGPab) to gliadin were linearly decreased as AGPab and antigen were diluted. Dot-blot and immunoblot assay showed that produced AGPab specifically reacted to gliadin and mainly $\alpha$-, $\beta$-, and ${\gamma}$-gliadin subunits. Enzyme-linked immuno- sorbent assay (ELISA) was applied for quantifi-cation of gliadins in Korean wheat cultivars and breeding lines by using AGPab. High reactions between AGPab and gliadins were found in wheat cultivars Olmil and Olgeurumil. Significant difference of optical densities for alcohol soluble proteins among crop species was found, as wheat showed the highest value (0.697) followed by rye (0.295), and barley (0.066).

• Korean Journal of Veterinary Research
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• v.32 no.4
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• pp.569-577
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• 1992

Group A 로타바이러스 VP6에 특이적으로 반응하는 단크론 항체를 이용하여 로타바이러스 감염이 의심되는 돼지 분변으로부터 로타 바이러스를 검색할 수 있는 효소면역측정법을 개발하였다. 이 효소면역측정법에서는 capture antibody로서 protein A-sepharose를 이용하여 단크론 항체로부터 순수 분리한 immunoglobulin을 사용하였으며 detecting antibody는 토끼 면역혈청으로부터 순수 분리한 immunoglobulin에 biotin을 label하여 사용하였다. 개발된 효소면역측정법의 민감도와 특이성을 전자현미경법 및 형광항체법의 것과 비교하여 보았을 때 서로 유사하였으며 분변재료로부터 로타바이러스를 검색하는데 유용한 것으로 나타났다. 개발된 효소면역측정법은 야외로부터 로타바이러스 검색을 위하여 수집된 많은 양의 분변재료를 실험실내에서 screen하는데 유용하게 사용될 것으로 생각된다.

• Food Science of Animal Resources
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• v.18 no.2
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• pp.149-156
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• 1998

Chicken beef pork meats and isolated soy protein (ISP) were heated at 10$0^{\circ}C$ for 30min and then heat-resistant proteins were fractionated to examine cross-resistant protein from chicken meat but not with beef pork or ISP. Dot blotting using the polyclonal antibody showed that the sen-sitivity for detecting chicken meat was 1$\mu$m and antibody-antigen reaction was dose-dependant. Results of dot blotting analysis to compare the amount of chicken meat present in arket meat products(Kentucky Frank sausage;chicken meat 46.52% and pork 24.92% vs Bulgogi Ham;chicken meat 28.89% and turkey 31.44%)showed that the significant differences between two meat products in terms of chicken meat concentrations. Dose-dependant dot-blotting reaction was also observed in chicken meat samples with various dilution.

• Korean Journal of Veterinary Service
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• v.23 no.2
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• pp.113-124
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• 2000

A total of 500 sera and lungs of slaughtered pigs were examined to investigate antibody titer, prevalence of pulmonary lesion, and interrelation among lung lesion score, type of pulmonary lesion and antibody titers by ELISA. The results obtained were as follows ; 1. The highest distribution of antibody titer was showed at 20 - 80 in M hyopneumoniae, 160-640 in P multocida type A and 160 - 640 in A pleuropneumoniae serotype 2 and 5. 2. The prevalence of pulmonary lesions was 84.0%, mean pulmonary lesion and mean lung score listed as 24.0$\pm$19.8% and 2.5$\pm$1.6, respectively. 3. In the prevalence of type of pulmonary lesion, enzootic pneumonia, pleuropneumonia and pleuritis were 58.2%, 10.0% and 15.8%, respectively. 4. Lung lesion score and type of pulmonary lesion were not interrelated with the distribution of antibody titer to specific pathogens, and causative pathogens of respiratory diseases were complicated with various bacteria.

• Biomedical Science Letters
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• v.21 no.1
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• pp.9-14
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• 2015

Mouse hepatitis virus (MHV) is a major pathogen in laboratory mice that usually leads to fatal diseases, such as hepatitis, multiple sclerosis, encephalitis, and respiratory disease. MHV has a high infection rate, and it needs to be detected as soon as possible to prevent its spread to other facilities. However, MHV detection by enzyme-linked immunosorbent assay (ELISA) often gives false positives; thus, it is very important that the results are confirmed as true positives in the early infection stage or distinguished as false positives with more accurate, reliable methods. Under microbiological screening, MHV ELISA-positive mice were found in four GFP-tagging transgenic mice. To verify the detection of the MHV antigen directly, reverse transcription polymerase chain reaction (RT-PCR) was performed, and the mice were determined to be MHV negative. Additional serum antibody-based screening was conducted with three different ELISA kits, and multiplexed fluorometric immunoassay (MFIA) was performed to confirm their accuracy/sensitivity. In brief, the ELISA kit for A59 nucleocapsid protein (MHV-A59N) revealed MHV ELISA positivity, while other ELISA kits (MHV-S lysate and MHV-JHM lysate) demonstrated MHV negativity. In MFIA, only the test for the recombinant A59 nucleocapsid antigen was MHV positive, which was consistent with the ELISA results. These results suggest that the ELISA kit with the recombinant A59 nucleocapsid antigen might induce non-specific MHV ELISA positivity and that confirmation is therefore essential.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.152-157
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• 2004

Gluten was extracted from domestic wheat flour using UTH buffer (4 M urea in 0.1 M Tris-HCl, pH 8.6) and validated by SDS-PAGE analysis for production of wheat flour products with reduced gluten content.. Anti-gluten polyclonal antibody was made by administering extracted gluten fraction on animal model. Anti-gluten serum titer of extracted gluten fraction was evaluated by ELISA, and that of antibody titer according to administration period. Anti-gluten sera were used for ELISA and immunoblot analysis before and after hydrolysis of gluten fraction at optimal pH and temperature condition for each protease. Gluten fraction separated by SDS-PAGE showed several bands covering 75 to 10 kDa, in which anti-gluten sera were 25, 34, and 45 kDa. Enzyme hydrolysis of gluten fraction revealed protein band sizes to be lower than 15 kDa. Content of pretense from bovine pancreas (b.p. protease) for gluten hydrolysis was estimated as 1 mg in 10 mL gluten fraction extracted for 4 hr.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.269-275
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• 1998

Anti-Neospora caninum antibody was detected in anti-Toxoplasma gondii positive and negative human sera by ELISA, western blot and immunofluorescence assay (IFA). Twelve cases out of 172 (6.7％) Toxoplasma-positive sera cross-reacted with both T. gondii and N. caninum antigens, and one out of 110 Toxoplasma-negative sera reacted with N. caninum antigen by ELISA. By western blot, all 12 sera reacted with T. gondii antigens with various banding patterns but specifically at 30 kDa (SAG 1), and 22 kDa （SAG2) bands. With N. caninum antigen, the number of reactive bands was reduced, however a 43 kDa band reacted in three cases in Toxoplasma-positive sera in addition to one in Toxoplasma-negative control sera. All sera of the Toxoplasma-positive group labeled surface membrane of T. gondii, but reacted differently with N. caninum. Fluorescence was detected in surface membrane, subcellular organelles, or both in N. caninum. And one case in the Toxoplasma-negative group also reacted with N. caninum strongly in subcellular organelles. This suggested that the antibody against N. caninum may be present in human sera although the positive rate was very low in this study. The possibility of human infection with N. caninum remains to be evaluated further.

• Development and Reproduction
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• v.9 no.2
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• pp.135-142
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• 2005

Vitellogenins(VTGs) are the precursor of egg-yolk proteins in most oviparous species from invertebrates to vertebrates. In oviparose vertebrates, VTGs are synthesized in the liver and transported through the blood to oocytes. In female fish, concentrations of plasma VTG increase rapidly at onset of vitellogenesis in the normal reproductive cycle. Male fishes also possess the gene for VTG, but plasma concentrations of the protein typically remain small, presumably due to low levels of endogenous estrogens. However, exposure of males to exogenous estrogenic mimics can result elevated. Therefore, the VTG in fish can be used as a useful biomarker for appropriate tools of endocrine disrupting compounds effects. In this studies, we prepared the test methods that can measure the plasma VTG level in the gobies that live in polluted area with mimic estrogen. For the purpose, we purified VTG of floating goby(Chaenogobius annularis) and prepared specific monoclonal and polyclonal antisera to yolk protein, then developed a sandwich competitive ELISA system for measurement of plasma VTG levels. Validation for the ELISA system using monoclonal and polyclonal antibodies against VTG was tested. The absorbance curve of serial dilutions of serum from vitellogenic female was paralleled to the standard curve of VTG, but normal male was not paralleled. The developed sandwich ELISA system was measured for VTG levels in plasma of common goby(Acanthogobius flaviman) and javeline goby(A. hasta) as well as in plasma of floating goby(C. annularis).