• 제목/요약/키워드: Antigen-antibody

검색결과 894건 처리시간 0.024초

포도구균의 A단백질을 이용한 효소면역법으로 살모넬라 O항원 검출 (An Improved Method for Detection of Salmonella Typhi O Antigen with Staphylococcal Protein A Using Enzyme Immunoassay)

  • 유문간;김금룡;이중기
    • 대한미생물학회지
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    • 제22권4호
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    • pp.445-451
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    • 1987
  • Coagglutination method is widely used for the diagnosis of Salmonella infection. This test, however, has a disadvantage of false positive reaction due to the coagglutination of staphylococci with non-specific immune complexes or anti-staphylococci antibody in serum. Salmonell O antigen was detected by enzyme immunoassay with protein A-bearing Staphylococcus aureus as in the solid phase. Horse radish peroxidase was labeled to IgG specific against Salmonella O antigen. This enzyme immunoassay was much more sensitive than conventional coagglutination method without false poitive agglutination. To improve the sensitivity for detection of Salmonella O antigen in samples, we tried to determine the optimal concentration of normal IgG that inhibits non-specific binding of horse radish peroxidase labeled IgG to staphylococci, and to establish the optimal condition of reaction between antigen-antibody complex and staphylococci. Non-specific binding of horse radish peroxidase labeled specific IgG to staphylococci was almost blocked when the enzyme labeled IgG was 500-fold diluted with phosphate buffered saline containing 2mg/ml of normal IgG. When staphylococci coated with antibody to Salmonella O antigen were mixed with antigen-antibody complex and then incubated for 1 hour at room temperature, the minimal detectable concentration of Salmonella O antigen was 1ng/ml. The sensitivity of enzyme immunoassay was 100-fold greater than a conventional coagglutination method. This enzyme immunoassay could be expected as an improved method for detection of other infectious agents.

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Affinity Maturation of an Anti-Hepatitis B Virus PreS1 Humanized Antibody by Phage Display

  • Yang, Gi-Hyeok;Yoon, Sun-Ok;Jang, Myung-Hee;Hong, Hyo-Jeong
    • Journal of Microbiology
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    • 제45권6호
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    • pp.528-533
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    • 2007
  • In a previous study we generated an anti-Hepatitis B Virus (HBV) preS1 humanized antibody (HzKR127) that showed in vivo HBV-neutralizing activity in chimpanzees. However, the antigen-binding affinity of the humanized antibody may not be sufficient for clinical use and thus affinity maturation is required for better therapeutic efficacy. In this study, phage display technique was employed to increase the affinity of HzKR127. All six amino acid residues (Glu95-Tyr96-Asp97-Glu98-Ala99-Tyr100) in the heavy (H) chain complementary-determining region 3 (HCDR3) of HzKR127 were randomized and phage-displayed single chain Fv (scFv) library was constructed. After three rounds of panning, 12 different clones exhibiting higher antigen-binding activity than the wild type ScFv were selected and their antigen-binding specificity for the preS1 confirmed. Subsequently, five ScFv clones were converted to whole IgG and subjected to affinity determination. The results showed that two clones (B3 and A19) exhibited an approximately 6 fold higher affinities than that of HzKR127. The affinity-matured humanized antibodies may be useful in anti-HBV immunotherapy.

Minireview on Recent Antibody-Related NMR Studies

  • Jang, Jinhwa;Kim, Ji-Hun
    • 한국자기공명학회논문지
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    • 제24권4호
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    • pp.129-135
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    • 2020
  • In a relatively short period, monoclonal antibodies have made dramatic success as therapeutics for various diseases such as cancers and autoimmune diseases and become an important development items for many pharmaceutical companies. In order to develop antibody drug, it is important to investigate the structural characteristics of both antibody and antigen. NMR studies on antibody are extremely challenging due to big huddles such as a big size of protein and isotope labeling, nevertheless, several studies have been reported in 10 years. Here, we analyzed 95 papers dealing with antibody-related NMR studies reported in recent 10 years. We categorized papers into 3 types: 1) structural characterization of antibody, 2) structural characterization of antigen using antibody, 3) amyloidosis caused by fragment of antibody. This work would shed new light on antibody-related NMR studies.

Immunological Properties of Recombinant Hepatitis B Surface Antigen Expressed in Mammalian Cell(C127)

  • Lee, Young-Soo;Kim, Byong-Kak;Choi, Eung-Chil
    • Archives of Pharmacal Research
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    • 제21권5호
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    • pp.543-548
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    • 1998
  • We examined the immunological properties of the recombinant hepatitis B surface antigen (r-HBsAg) which was expressed in mammalian cell (C127). The cross-immunity of r-HBsAg and plasma-derived hepatitis B surface antigen (p-HBsAg) were tested using Western blotting and ELISA with guinea pig polyclonal antibody and naturally infected human-derived antibody and the both antigens show the same results in their response pattern and intensity, which indicate they have a good cross-immunity. from the measurement of $ED_{50}$ after formalin- or heat-inactivation, both r-HBsAg and p-HBsAg and p-HBsAg showed $ED_{50}$ of 0.2-0.3 in formalin-inactivaton, while r-HBsAg was 0.05-0.09 and p-HBsAg was 0.03-0.07 in heat-inactivation, which means heat-inactivation method is 3-4 times superior in immunogenicity. In the immunopersistency test performed in guinea pig for the period of 3 months with two different adjuvants, antibody titer was 34.2 with muramyl dipeptide adjuvant, which was 1.8 times greater than the antibody titer of 18.9 with $AIPO_{4}$ adjuvant. the mutagenicity of r-HBsAg has the same cross-immunity with p-HBsAg, and heat-inactivation method and muramyl dipeptide adjuvant allow development of r-HBsAg vaccine with excellent immunogenicity.

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장독성대장균 F41 섬모항원에 대한 특이난황항체 생산 (Production of a Specific Yolk Antibody against Enterotoxigenic E. coli F41 Fimbrial Antigen)

  • 신순오;김정우
    • Journal of Animal Science and Technology
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    • 제44권5호
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    • pp.633-642
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    • 2002
  • 1. ETEC F41 균주로부터 분리한 섬모항원의 분자량은 29.5 kDa으로 나타났으며, western blot을 통하여 섬모항원임을 확인하였다. 2. 분리한 섬모항원의 농도를 50 ${\mu}g$/$m\ell$, 200 ${\mu}g$/$m\ell$, 600 ${\mu}g$/$m\ell$로 조정 후 산란계에 접종하였다. 이 후 ELISA법을 이용하여 난황의 항체역가를 측정한 결과 최고치가 320,000(antigen 50${\mu}g$/$m\ell$), 450,000(antigen 200${\mu}g$/$m\ell$), 320,000(anti- gen 600${\mu}g$/$m\ell$)으로 나타났다. 3. F41난황항체와 K88, K99, 987P 섬모항원과의 교차반응을 ELISA법을 이용하여 조사해본 결과 난황항체를 30,000배 희석 시 교차반응이 없었다. 4. 실험실조건하에서 난황항체의 항원결합능력을 조사한 결과, 동결건조한 WSF을 2${\sim}$4 mg/$m\ell$ 첨가 시 균체의 농도가 $10^9$ CFU/$m\ell$에서 $10^5$ CFU/$m\ell$로 급격하게 감소하였다.

종특이 단세포군항체에 반응하는 간흡충의 당질항원 한 가지 (A carbohydrate antigen of Clonorchis sinensis recognized by a species-specific monolonal antibody)

  • 용태순;이종석
    • Parasites, Hosts and Diseases
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    • 제34권4호
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    • pp.279-282
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    • 1996
  • 간흡충 특이 단세포군항체인 CsHyb 0605-23과 반응하는 간흡충 항원의 특성을 밝히기 위하여 간흡충의 성충 조항원을 당지질 당질 단백으로 각각 분리한 후 각각 항원으로 사용하여 단세포 군항체와 효소떤역흡착검사법을 실시하였다. 그 결과. 오직 당질분획만이 단세포군항체와 반응하였다. 당질항원을 sodiumperiodate를 사용하여 약하게 산화시키자 단세포군항체와의 반응도가 떨어졌다. 따라서 이 단세포군항체에 반응하는 간흡충의 항원 및 항원결정기는 당질로 생각된다.

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효소-항체의 결합 및 효소면역측정 방법의 연구 (Study on Antibody-enzyme Coupling and Enzyme Immunoassay Methods)

  • 장선일
    • 동의생리병리학회지
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    • 제18권3호
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    • pp.874-879
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    • 2004
  • Alakaline phosphatase (ALP)- or horseradish peroxidase (HRP)-antibody conjugate was used frequently on the immunological detection methods such as enzyme-linked immunosobent assay (ELISA), immunobolt, immunohistochemistry. The classical enzyme-antibody coupling method by one-step (direction) injection of glutaraldehyde bring into being disadvantage such as low sensitivity of antigen detection because of homopolymers. This study was modified with the dialysis glutaraldehyde method to provide simple coupling through E-amino residues present in most protein. The dialysis glutaraldehyde coupling effects were better than the classical one-step glutaraldehyde injection in antigen detection of ELISA and immunobolt. Optimal dose of the dialysis glutaraldehyde solution was 0.10-0.25 %. This results suggest that the dialysis glutaraldehyde coupling method can readily applied to antigen detection of in vitro and in vivo.

효소면역법에 의한 소 로타바이러스 항원 검출 (Detection of bovine rotavirus antigen by enzyme linked immunosorbent assay)

  • 안재문;유기조;이용희;이종인
    • 한국동물위생학회지
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    • 제19권1호
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    • pp.30-38
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    • 1996
  • Enzyme-linked immunosorbent assay (ELISA) was developed to detect rotavirus antigen in fecal samples using VP6-specific monoclonal antibody(2B12). The ELISA for rotavirus antigen detection found to have specificity to all bovine and porcine rotaviruses tested but not to bovine viral diarrhea virus and bovine coronavirus. The ELISA appeared to have similar sensitivity and specificity compared to fluorescence antibody assay(FA) and electropherotyping (PAGE).

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해양에서 분리한 Vibrio vulnificus의 면역학적 특성 (Immunological Characterization of Vibrio vulnificus isolated from Marine Environment)

  • 정초록;전유진;허문수
    • 환경생물
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    • 제19권4호
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    • pp.302-312
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    • 2001
  • Immunoglobulin G was purified by 40% $(NH_4)_2SO_4$ precipitation, DEAE-Sephadex, Sephadex G-150 column chromatographies from rabbit antiserum against V. vulnificus ATCC 27562 O antigen and used for immunological test for V. vulnificus isolates. The profiles of cell lysate total protein and outer membrane protein from the isolates were analyzed by SDS-PAGE and densitometry. The overall profiles in all isolates were similar. Distict protein band was observed in comparison with V. parahaemolyticus. Western Blotting with rabbit Immunoglobulin G against cell lysates and OMP of V. vulnificus isolates showed a strong antigenic response to antigen 66, 60, 54, 48, 33 and 26 kDa which were common to all strains examined. The 26 kDa antigen showed V. vulnificus specific antigen in comparison with Vibrio parahaemolyticus. A sandwich enzyme-linked immunosorbent assay was developed by using rat anti-V. vulnificus ATCC 27562 polyclonal antibodies as capture antibody, a purified rabbit IgG antibody as detector antibody, and goat anti-rabbit IgG-alkaline phosphatase conjugate as developer antibody. When four V. vulnificus isolates were tested, the reactivity showed from 50 to 70% by sandwich ELISA.

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추백리의 혈청학적 진단법에 관한 연구 (Studies on serological tests for pullorum disease)

  • 김정태;심항섭;김태종;고태오;우종태;유기승;박유순
    • 한국동물위생학회지
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    • 제21권3호
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    • pp.313-323
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    • 1998
  • In order to establish a sensitive and specific diagnostic method for detection of antibody to Salmonella pullorum, a enzyme-linked immunosorbent assay(ELISA) was designed and standardized. The diagnostic efficacy of the established ELISA was compared with that of the serum plate agglutination test and immunodiffusion test for pullorum disease. 1. The chicken hyperimmune sera to Salmonella pullorum, S gallinarum, S typhimurium and S typhi were shown the cross reaction to S pullorum antigen by serum plate agglutination test. 2. When compared the cross reaction titer of microplate agglutination test for chickens hyperimmune sera, it was found that the titer were 64 in S pullorum, 32 in S gallinarum, 4 in S typhimurium and 8 in S typhi, respectively. 3. When compared the specificity of various antigen(HA, EA, PA and SA) by the immunodiffusion test, the most suitable antigen was phenol-treated bactrium. 4. The optimal concentration of S pullorum antigen for ELISA was 1 : 160 dilution of bacterium. 5. The efficacy of the ELISA for detection of S pullorum antibody was compared with serum Plate agglutination test and immunodiffusion test in chickens infected with S pullorum. The antibody was first detected at 6 days after infection using three tests examined. The antibody was alldetected at 9 days by ELISA, at 12 days by serumplate agglutination test, at 15 days by immunodiffusion test.

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