• Title/Summary/Keyword: H-2 antigen

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Dot-Blot Immunoassay of Fasciola gigantica Infection using 27 kDa and Adult Worm Regurge Antigens in Egyptian Patients

  • Kamel, Hanan H.;Saad, Ghada A.;Sarhan, Rania M.
    • Parasites, Hosts and Diseases
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    • v.51 no.2
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    • pp.177-182
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    • 2013
  • The purpose of the present study was to evaluate the potential role of the 27-Kilodalton (KDa) antigen versus Fasciola gigantica adult worm regurge antigens in a DOT-Blot assay and to assess this assay as a practical tool for diagnosis fascioliasis in Egyptian patients. Fasciola gigantica antigen of an approximate molecular mass 27- (KDa) was obtained from adult worms by a simple elution SDS-PAGE. A Dot-Blot was developed comparatively to adult worm regurge antigens for the detection of specific antibodies from patients infected with F. gigantica in Egypt. Control sera were obtained from patients with other parasitic infections and healthy volunteers to assess the test and compare between the antigens. The sensitivity, specificity, positive and negative predictive values of Dot-Blot using the adult worm regurge were 80%, 90%, 94.1%, and 69.2% respectively, while those using 27-KDa were 100% which confirms the diagnostic potential of this antigen. All patients infected with Fasciola were positive, with cross reactivity reported with Schistosoma mansoni serum samples. This 27-KDa Dot-Blot assay showed to be a promising test which can be used for serodiagnosis of fascioliasis in Egyptian patients especially, those presenting with hepatic disease. It is specific, sensitive and easy to perform method for the rapid diagnosis particularly when more complex laboratory tests are unavailable.

Role of enzyme immunoassay for the Detection of Helicobacter pylori Stool Antigen in Confirming Eradication After Quadruple Therapy in Children (소아에서 4제요법 후 enzyme immunoassay에 의한 Helicobacter pylori 대변 항원 검출법의 유용성에 대한 연구)

  • Yang, Hye Ran;Seo, Jeong Kee
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.7 no.2
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    • pp.153-162
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    • 2004
  • Purpose: The Helicobacter pylori stool antigen (HpSA) enzyme immunoassay is a non-invasive test for the diagnosis and monitoring of H. pylori infection. But, there are few validation studies on the HpSA test after eradication in children. The aim of this study was to assess the diagnostic accuracy of HpSA enzyme immunoassay for the detection of H. pylori to confirm eradication in children. Methods: From January 2001 to October 2003, 164 tests were performed in 146 children aged 1 to 17.5 years (mean $9.3{\pm}4.3$ years). H. pylori infection was confirmed by endoscopy-based tests (rapid urease test, histology, and culture). All H. pylori infected children were treated with quadruple regimens (Omeprazole, amoxicillin, metronidazole and bismuth subcitrate for 7 days). Stool specimens were collected from all patients for the HpSA enzyme immunoassay (Primier platinum HpSA). The results of HpSA tests were interpreted as positive for $OD{\geq}0.160$, unresolved for $$0.140{\leq_-}OD$$<0.160, and negative for OD<0.140 at 450 nm on spectrophotometer. Results: 1) One hundred thirty-one HpSA tests were performed before treatment. The result of HpSA enzyme immunoassay showed three false positive cases and one false negative case. The sensitivity, specificity, positive predictive value, and negative predictive value of HpSA enzyme immunoassay before treatment were 96.4%, 97.1%, 90%, and 99%, respectively. 2) Thirty-three HpSA enzyme immunoassay were performed at least 4 weeks after eradication therapy. The results of HpSA enzyme immunoassay showed two false positive cases and one false negative case. The sensitivity, specificity, positive predictive value, and negative predictive value after treatment were 88.9%, 91.7%, 80%, and 95.7%, respectively. Conclusion: Diagnostic accuracy of the HpSA enzyme immunoassay after eradication therapy was as high as that of the HpSA test before eradication therapy. The HpSA enzyme immunoassay was found to be a useful non-invasive method to confirm H. pylori eradication in children.

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Overview on Molecular Toxicological Aspects of Helicobacter pylori Virulence Factor, Cytotoxin-associated Antigen A (CagA) (헬리코박터 파이로리의 병원성 단백질, CagA에 대한 분자 독성학적 측면에서의 고찰)

  • Kim Byung J.;Jung Hwa Jin;Hwang Jee Na;Kang Seok Ha;Oh Se-Jin;Seo Young Rok
    • Toxicological Research
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    • v.20 no.3
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    • pp.179-185
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    • 2004
  • Helicobacter pylori (H. pylori) infects more than half of the people in the world as a major microbe to cause most of gastric diseases. Recently, cytotoxin associated-antigen A (CagA) is believed as one of the most important virulence factors of H. pylori. Molecular toxicological pathway of CagA is necessary to investigate for understanding the pathological and toxicological aspects of H. pylori, since this virulence protein harasses intercellular processes of host cells to get profit for the survival of H. pylori. CagA is coded from cag pathogenicity island (cag PAI) and translocated into host cells by Type 4 secretion system (TFSS). Tyrosine phosphorylation of CagA targets Src homology 2-containing phosphotyrosine phosphatase (SHP-2) to form a CagA-SHP-2 complex. This complex depends on the similarity of sequence between EPIYA motif and Src homology 2 domain (SH2 domain) of CagA. The generation of growth factors is an essential role of CagA in protecting and healing gastric mucosa for the survival of H. pylori. On the other hand, the activation of IL-8 by CagA induces neutrophils generating inflammation and free radicals. Indeed, free radicals are well known carcinogen to induce DNA damage. In addition, the transduction of mitogen-activation signal by CagA is one of the interesting features to understand how to cause cancer. The relationship between cancer and inflammation with CagA was mainly discussed in this review.

Stability of antibody during heat treatment and storage in immunized milk with Helicobacter pylori antigen (Helicobacter pylori 항원을 이용한 면역우유의 열처리와 저장 중 항체의 안전성)

  • Jeong Eun-Ju;Park La-Young;Bae Man-Jong;Lee Shin-Ho
    • Food Science and Preservation
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    • v.13 no.2
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    • pp.223-227
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    • 2006
  • Optimal heat treatment conditions for maintaining the immune-activity of immunized milk with Helicobacter pylori antigen were studied Total bacterial count of immunized milk with H. pylori antigen decreased according to the increasing heating temperature and time. The viable tell number of immunized milk was $10^3\;CFU/mL$ after heat treatment for 30 min at $60^{\circ}C$, and coliform bacteria did not appear in immunized milk after heat treatment Immune-activity measured in terms of IgG concentration was maintained up to 99.99% after heat treatment for 30min at $60^{\circ}C$, but decreased rapidly below 50% after heat treatment above $70^{\circ}C$. The quality characteristics of immunized milk were examined during storage at $2^{\circ}C,\;4^{\circ}C\;and\;10^{\circ}C$. The pH, titratable acidity and total bacterial count were not changed significantly during 21 day storage at $2^{\circ}C\;and\;4^{\circ}C$, but rapidly changed after 7 day storage at $10^{\circ}C$. The immune-activity was kept well for 14 day storage at $2^{\circ}C,\;4^{\circ}C\;and\;10^{\circ}C$ but decreased rapidly after 14 days at every temperatures tested.

Changes in the Titer of Tooth Root Antibodies Accompanying Root Resorption Associated with Orthodontic Tooth Movement (치아이동시 치근 흡수에 따른 치근항체의 역가 변화)

  • Park, Soo-Byung;Son, Woo-Sung
    • The korean journal of orthodontics
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    • v.24 no.2
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    • pp.303-317
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    • 1994
  • This study was designed to measure the changes in the titer of tooth root antibodies accompanying root resorption associated with orthodontic tooth movement in dogs to explore a role of the specific immune response in root resorption during orthodontic tooth movement. Five adult mongrel dogs, 2 years of age, were used in the study. Six lower incisors were extracted as sources of homologous antigen in the dogs. Tooth root antigen preparations were made from a 6M Guanidine-HCl-10% EDTA(pH5.0) extract of these root dentins. Root resorption was elicited by intrusion of six maxillary incisors with 200-250gm intrusive force. In 9th week, resorbing six maxillary anterior teeth were extracted. Serum samples were taken from each dog prior to intrusion and weekly for 11 consecutive weeks. Serum autoantibody titers were determined with an enzyme-linked immunosorbent assay. As controls for antibody specificity, sera which were previously incubated with tooth root antigen as well as sera to an unrelated bacterial antigen (Porphyromonas gingivalis 33277) for 3 hours at 25 were measured in all runs. Root resorption was monitored monthly using occlusal radiographs. And then root resorption patterns were observed with a zoom stereo microscope (Model SZH-121, Olympus optical Co. Ltd.). Incisors did not show clear radiographic evidence of significant and progressive root resorption, but periodontal ligament space had widened. But root resorption was observed on the apical regions of the maxillary incisors with a zoom stereo microscope. Teeth showed the shallow depression generally accompanying deep resorption. These demonstrate a slight tendency for an immediate decrease followed by rebound to levels above the pre-treatment baseline. A peak titer of autoantibody to dentin antigen occurred on day 28, then steadily decreased during the 9th week period as the roots resorbed and then rapidly spiked in animals when the resorbing teeth were extracted. When sera is incubated with tooth root antigen, serum activity in the ELISA was almost absent. This is because serum activity in the ELISA could be removed by absorption of the serum with dog dentin antigen. Serum ELISA activity to the unrelated bacterial antigen remained essentially unchanged in all animals throughout the experimental period. When the time course of changes in autoantibody to homologous tooth root antigen prepatration and unrelated bacterial antigen was compared, no significant differences were found(${\alpha}=0.05$). In general, the overall pattern of changes in autoantibody was similar to the two antigens. These findings suggest the possibility that these immunologic changes precede a significant development of root resorption lesions rather than merely reflecting their presence. Therefore, this suggests that the changes of antibody levels may have some predictive value for root resorption.

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Carex pumila Extract Supresses Mast Cell Activation and IgE-Mediated Allergic Response in Mice (좀보리사초의 IgE 매개성 알레르기 반응 억제 효과 및 기전)

  • Lim, Hannah;Kim, Young Mi
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.356-362
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    • 2014
  • Allergic diseases have increased rapidly over the past decades, affecting an estimated 20~30% of the population in developed countries. In this study, we investigated whether or not a typical costal sand dune plant Carex pumila (CPE) suppresses the activation of mast cells and IgE-mediated allergic response in vitro and in vivo. As the results, the extract of Carex pumila inhibited antigen-stimulated degranulation in RBL-2H3 cells and Bone marrow-derived mast cells (BMMCs), and IgE-mediated passive cutaneous anaphylaxis (PCA) in mice. CPE also suppressed the production of pro-inflammatory cytokines, TNF-${\alpha}$ and IL-4, in antigen-stimulated mast cells. As its mechanism of action, CPE inhibited the activation of Syk in $Fc{\varepsilon}RI$-mediated signalling pathway, and that of LAT, a downstream adaptor molecule of Syk, in a dose-dependent manner. CPE also suppressed the activation of mitogen-activated protein (MAP) kinases, p38, ERK1/2, JNK, and Akt. Altogether, CPE inhibited mast cell activation and IgE-mediated allergic response by antigen through suppressing the activation of Syk. These results suggest that CPE may be useful for the treatment of allergic diseases.

Expression and Characterization of Uropathogenic Escherichia coli Adhesin Protein Linked to Cholera Toxin A2B Subunits in Escherichia coli TB1

  • Lee, Yong-Hwa;Ryu, Dong-Kyun;Kim, Byung-Oh;Pyo, Suhk-Neung
    • Journal of Microbiology and Biotechnology
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    • v.13 no.4
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    • pp.552-559
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    • 2003
  • The FimH subunit of type 1-fimbriated Escherichiu coli (E. coli) has been determined as a major cause for urinary tract infections. Thus, to produce a possible vaccine antigen against urinary tract infections, the fimIH gene was genetically coupled to the ctxa2b gene and cloned into a pMAL-p2E expression vector. The chimeric construction of pMALfimH/ctxa2b was then transformed into E. coli K-12 TB1 and its nucleotide sequence was verified. A fusion protein, based on fusing adhesin to the cholera toxin subunit A2B (CTXA2B), was induced with 0.01 mM isopropyl-${\beta}-D-thiogalactoside$ (IPTG) for 4 h at $37^{\circ}C$ to yield a soluble fusion protein. The fusion protein was then purified by affinity chromatography. The expressed fusion protein was confirmed by SDS-PAGE and Western blotting using antibodies to the maltose binding protein (MBP) or the cholera toxin subunit B (CTXB), plus the N-terminal amino acid sequence was also analyzed. The orderly-assembled fusion protein was confirmed by a modified $G_{Ml}-ganglioside$ ELISA, using antibodies to adhesin. The results indicated that the purified fusion protein was an adhesin/CTXA2B protein containing E. coli adhesin and the $G_{Ml}-ganglioside$ binding activity of CTXB. Accordingly, this adhesin/CTXA2B protein may be a potential antigen for oral immunization against uropathogenic E. coli.

Studies on Sexing of Mouse Embryos with Rat H-Y Antisera (흰쥐 H-Y 항혈청을 이용한 생쥐배의 성감별에 관한 연구)

  • 최화식;임경순;조병대;정진관;오성종;양보석
    • Korean Journal of Animal Reproduction
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    • v.17 no.4
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    • pp.305-310
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    • 1994
  • These expriments were carried out to investigate existence of H-Y antibody in the rat serum immunized against H-Y antigen from rat spleen cells and effect of H-Y antiserum on development of mouse male embryos. The results obtained were summerized as follows : 1. When mouse embryos were cultured for 48∼72 hrs in the Ham's F10 containing 16% of FBS(fetal bovine serum) or RNS(rat normal serum), percentages of embryos developed from 2, 4, 8 and 16-cell embryo to morulae were 20, 27, 94 and 100%, respectively, in FBS and 8, 7, 94 and 100%, respectively, in RNS. Eight to 16-cell embryos showed no difference in development rate between FBS adn RNS. 2. When 8∼16-cell mouse embryos were cultured for 24∼48 hrs in the Ham's F10 containing FBS, RNS+GPC(guinea pig complement) and RAS(rat antiserum)+GPC, proportions of embryos developed to the expanded blastocyst stage were 100, 82.4 and 52.1∼53.6%(ave.52.9), respectively, so that it was suggested that rat antiserum suppressed development of male embryos. 3. When 8∼16-cell mouse embryos were cultured for 24∼48 hrs in the Ham's F10 containing FBS, RNS, RNS+GPC and RAS+GPC, proportions of embryos developed to the expanded blastocyst stage were 94.5, 90.9, 82.3 and 47%, respectively, and the embryos developed in the medium containing RAS+GPC seemed to be female. These results indicated that the antisera prepared through immunized against H-Y antigen from rat spleen cell, possessed H-Y antibody which supressed development of male embryos.

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Effects of cyclosporin A and tacrolimus on the cross-presentation capability of dendritic cells

  • Lee, Young-Ran;Park, Eun-Ju;Im, Sun-A;Song, Suk-Gil;Lee, Chong-Ki
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.136.2-136.2
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    • 2003
  • Previously, we showed that cyclosporin A and tacrolimus, but not rapamycin, inhibit MHC class I-restricted presentation of exogenous antigen in dendritic cells (DCs). We further characterized the effects of cyclosporin A and tacrolimus on the uptake, processing and cross-presentation of a model antigen, ovalbumin (OVA), in DCs. Treatment of DCs with cyclosporin A or tacrolimus did not inhibit phagocytic activity of DCs. Instead, treatment of DCs with cyclosporin A or tacrolimus inhibited the expression of $H-2K^b$/ molecules complexed with the OVA peptied, SIINFEKL, specifically. (omitted)

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The Optimal Activation State of Dendritic Cells for the Induction of Antitumor Immunity (항종양 면역반응 유도를 위한 수지상세포의 최적 활성화 조건)

  • Nam, Byung-Hyouk;Jo, Wool-Soon;Lee, Ki-Won;Oh, Su-Jung;Kang, Eun-Young;Choi, Yu-Jin;Do, Eun-Ju;Hong, Sook-Hee;Lim, Young-Jin;Kim, Ki-Uk;Jeong, Min-Ho
    • Journal of Life Science
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    • v.16 no.6
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    • pp.904-910
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    • 2006
  • Dendritic cells (DCs) are the only antigen presenting cells (APCs) capable of initiating immune responses, which is crucial for priming the specific cytotoxic T lymphocyte (CTL) response and tumor immunity. Upon activation by DCs, CD4+ helper T cells can cross-prime CD8+ CTLs via IL-12. However, recently activated DCs were described to prime in vitro strong T helper cell type 1 $(Th_1)$ responses, whereas at later time points, they preferentially prime $Th_2$ cells. Therfore, we examined in this study the optimum kinetic state of DCs activation impacted on in vivo priming of tumor-specific CTLs by using ovalbumin (OVA) tumor antigen model. Bone-marrow-derived DCs showed an appropriate expression of surface MHC and costimulatory molecules after 6 or 7-day differentiation. The 6-day differentiated DCs pulsed with OVA antigen for 8 h (8-h DC) and followed by restimulation with LPS for 24 h maintained high interleukin (IL)-12 production potential, accompanying the decreased level in their secretion by delayed re-exposure time to LPS. Furthermore, immunization with 8-h DC induced higher intracellular $interferon(IFN)-{\gamma}+/CD8+T$ cells and elicited more powerful cytotoxicity of splenocytes to EG7 cells, a clone of EL4 cells transfected with an OVA cDNA, than immunization with 24-h DC. In the animal study for the evaluation of therapeutic or protective antitumor immunity, immunization with 8-h DC induced an effective antitumor immunity against tumor of EG7 cells and completely protected mice from tumor formation and prolonged survival, respectively. The most commonly used and clinically applied DC-based vaccine is based on in vitro antigen loading for 24 h. However, our data indicated that antigen stimulation over 8 h decreased antitumor immunity with functional exhaustion of DCs, and that the 8-h DC would be an optimum activation state impacted on in vivo priming of tumor-specific CTLs and subsequently lead to induction of strong antitumor immunity.