• Title/Summary/Keyword: Surface antigen

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Development of Chemiluminescence Immunoassay(CIA) & ELISA for the Detection of Anti-sperm Antibodies in Male Serum (항정자 항체 검출을 위한 CIA 및 ELISA 개발을 위한 기초 연구)

  • Kim, S.C.;Lee, K.S.;Kim, Y.K.;Kim, C.K.;Choi, K.H.;Kwon, O.J.;Kim, J.B.
    • Clinical and Experimental Reproductive Medicine
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    • v.17 no.1
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    • pp.71-80
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    • 1990
  • New immunoassay systems for the detection of anti-sperm antibodies were developed. For this, sperm surface protein was purified by the immunoaffinity column prepared by the coupling of rabbit anti-human IgG antibodies to Sepharose-4B. Fraction eluted by tris-HCI buffer containing SDS showed a single band having molecular weight of about 60KD on electrophoresis. Enzyme HRP labelled goat anti-human IgG and chemiluminescence aminobutylethyl-isoluminol(ABEI) labelled rabbit anti-human IgG were used for ELISA and CIA, respectively. These two labelled conjugate bound well with human IgG. When serum dilution curves were made to titrate positive serums, two kinds of curves with steep and sluggish slopes were obtained Serum samples were categorized into 3 groups: positive, weak positive and negative based on slope of curve and O.D. values at 1:160 dilution of serum. When ELISA and CIA were compared to conventional method Kibrick test by the determinations of 62 male serums with different diagnosis, the results of ELISA and CIA agreed well, but both disagreed with that of Kibrick test. This study showed that purified sperm surface antigen can be used to develope solid-phase immunoassay systems such as ELISA and CIA which may eliminate the problems encounted the immobilization of living sperm in other tests.

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Immunomodulatory activities of ethanolic extract of Drynariae Rhizoma (골쇄보(骨碎補) ethanol 추출물의 면역 조절 작용에 관한 연구)

  • Lee Ki-Uk;Jeong Ji-Cheon
    • The Journal of Internal Korean Medicine
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    • v.25 no.1
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    • pp.16-27
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    • 2004
  • In the traditional Chinese medicine, Drynariae Rhizoma (DR) has been reported as a good enhancer for bone healing. DR, a plant widely used in the traditional medicinal systems of Korea, has been reported to possess antiviral, antibacterial and anti-inflammatory activities. Modulation of immune response to alleviate disease has been of interest for a long time. Plant extracts have been widely investigated for possible immunomodulatory properties. Thus, I have evaluated the anticellular and immunomodulatory properties of ethanolic extract of DR. DR extract inhibited proliferation of mitogen (phytohaemagglutinin; PHA) and antigen (purified protein derivative; PPD)-stimulated human peripheral blood mononuclear cells (PBMCs). In addition, DR inhibited growth of several cell lines of mouse and human origin. It also inhibited production of nitric oxide (NO), interleukin-2 (IL-2) and tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$. Intracytoplasmic $interferon-{\gamma}\;(IFN-{\gamma})$ and expression of cell surface markers, CD16 and HLA-DR, on human PBMC, were not affected on treatment with DR but CD25 expression was down regulated. This study demonstrates the antiproliferative and immunosuppressive potential of ethanolic extract of DR in vitro.

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Inhibition of Human $CD8^+$ Cytotoxic T Lymphocyte (CTL) -mediated Cytotoxicity in Porcine Fetal Fibroblast Cells by Overexpression of Human Cytomegalovirus Glycoprotein Unique Short (US) 2 Gene

  • Park, K-W.;Yoo, J.Y.;Choi, K.M.;Yang, B.S.;Im, G.S.;Seol, J.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.1
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    • pp.20-25
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    • 2009
  • Xenotransplantation of pig organs into humans is a potential solution for the shortage of donor organs for transplantation. However, multiple immune barriers preclude its clinical application. In particular, the initial type of rejection in xenotransplantation is an acute cellular rejection by host $CD8^+$ cytotoxic T lymphocyte (CTL) cells that react to donor major histocompatibility complex (MHC) class I. The human cytomegalovirus (HCMV) glycoprotein Unique Short (US) 2 specifically targets MHC class I heavy chains to relocate them from the endoplasmic reticulum (ER) membrane to the cytosol, where they are degraded by the proteasome. In this study we transfected the US2 gene into minipig fetal fibroblasts and established four US2 clonal cell lines. The integration of US2 into transgenic fetal cells was confirmed using PCR and Southern blot assay. The reduction of Swine Leukocyte Antigen (SLA)-I by US2 was also detected using Flow cytometry assay (FACS). The FACS analysis of the US2 clonal cell lines demonstrated a substantial reduction in SLA-I surface expression. The level (44% to 76%) of SLA-I expression in US2 clonal cell lines was decreased relative to the control. In cytotoxicity assay the rate of $CD8^+$ T cell-mediated cytotoxicity was significantly reduced to 23.8${\pm}$15.1% compared to the control (59.8${\pm}$8.4%, p<0.05). In conclusion, US2 can directly protect against $CD8^+$-mediated cell lysis. These results indicate that the expression of US2 in pig cells may provide a new approach to overcome the CTL-mediated immune rejection in xenotransplantation.

Differentiation of Osteoblast Progenitor Cells from Human Umbilical Cord Blood (제대혈액에서 골조직 특이세포로의 분화)

  • Hong, Seung-Jin;Lee, Eun-A;Chae, Gue-Tae;Han, Hoon
    • IMMUNE NETWORK
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    • v.2 no.3
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    • pp.166-174
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    • 2002
  • Background: Human umbilical cord bloods, which could be taken during the delivery are utilized as a source of hematopoietic stem cells. Also in cord blood, there are several kinds of stem cells such as endothelial and mesenchymal stem cells. Methods: We isolated the mesenchymal stem cells from human umbilical cord bloods and confirmed the differentiation of these cells into osteoblast progenitor cells. The mesenchymal stem cells derived from umbilical cord blood have the ability to differentiate into specific tissue cells, which is one of characteristics of stem cells. These cells were originated from the multipolar shaped cells out of adherent cells of the umbilical cord blood mononuclear cell culture. Results: The mesenchymal stem cells expressed cell surface antigen CD13, CD90, CD102, CD105, ${\alpha}$-smooth muscle actin and cytoplasmic antigen vimentine. Having cultrued these cells in bone formation media, we observed the formation of extracellular matrix and the expression of alkaline phosphatase and of mRNA of cbfa-1, ostoecalcin and type I collagen. Conclusion: From these results we concluded that the cells isolated from the umbilical cord blood were mesenchymal stem cells, which we could differentiate into osteoblast when cultured in bone formation media. In short, it is suggested that these cells could be used as a new source of stem cells, which has the probability to alternate the embryonic stem cells.

Electrochemical Immunosensor Based on the ZnO Nanorods Inside PDMS Channel for H7N9 Influenza Virus Detection (PDMS 채널 내부에 성장된 산화아연 나노막대를 이용한 H7N9 인플루엔자 바이러스 전기화학 면역센서)

  • Han, Ji-Hoon;Lee, Dongyoung;Pak, James Jungho
    • Journal of Sensor Science and Technology
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    • v.23 no.4
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    • pp.278-283
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    • 2014
  • In this study, we propose an immunosensor using zinc oxide nanorods (NRs) inside PDMS channel for detecting the influenza A virus subtype H7N9. ZnO with high isoelectric point (IEP, ~9.5) makes it suitable for immobilizing proteins with low IEP. In this proposed H7N9 immunosensor structure ZnO NRs were grown on the PDMS channel inner surface to immobilize H7N9 capture antibody. A sandwich enzyme-linked immunosorbent assay (ELISA) method with was used 3,3',5,5' tetramethylbenzidine (TMB) for detecting H7N9 influenza virus. The immunosensor was evaluated by amperometry at various H7N9 influenza antigen concentrations (1 pg/ml - 1 ng/ml). The redox peak voltage and current were measured by amperometry with ZnO NWs and without ZnO NWs inside PDMS channel. The measurement results of the H7N9 immunosensor showed that oxidation peak current of TMB at 0.25 V logarithmically increased from 2.3 to 3.8 uA as the H7N9 influenza antigen concentration changed from 1 pg/ml to 1 ng/ml. And then we demonstrated that ZnO NRs inside PDMS channel can improve the sensitivity of immunosensor to compare non-ZnO NRs inside PDMS channel.

A Study on Performance Evaluation of CEA kits (CEA 키트들 간의 성능 평가에 대한 고찰)

  • Ha, Dong hyuk;Sin, Hee Jung;You, Tae min;Noh, Kyoung Woon
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.1
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    • pp.76-79
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    • 2018
  • Purpose Carcinoembryonic antigen (CEA) is cell-surface 180-200 kDa glycoprotein that is overexpressed in breast, stomach pancreas, lung, and colorectal cancers. CEA was first described in 1965 by Gold and Freedman and then serum CEA of colorectal cancer patients was first measured in 1969 by radioimmunoassay by Thomson. CEA is currently most widely used tumor marker in the clinic for management of colorectal cancer. Various CEA test kits have been developed and commercialized. CEA kits from different manufacturers might have different test results because of different reagents and protocol. The purpose of this study was to compare results of four commercial available CEA kits. Materials and Methods This study was designed to evaluate four commercially available CEA kits using serum samples acquired from 120 patients who visited our clinic. Test results were compared and analyzed according to the respective test methods. High concentration samples were diluted with saline and diluted solution. Results All of the four kits showed a significant correlation within the reference value. However, three of the four kits used for the dilution test using high concentration samples showed the hook effect. Conclusion Results of the present study showed that It is important to establish the standardized dilution standards for the high-concentration specimens to manage the error of the test result by the hook effect.

Effects of Anti-B7.1/B7.2 Antibodies on LPS-Stimulated Macrophages

  • Won, Tae-Joon;Huh, Yoon-Joo;Lim, Young-Tae;Song, Dong-Sup;Hwang, Kwang-Woo
    • Biomolecules & Therapeutics
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    • v.18 no.4
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    • pp.463-468
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    • 2010
  • T-cell activation depends on signals received by the T-cell receptor and CD28 co-stimulatory receptor. Since B7.1 and B7.2 molecules expressed on the surface of antigen presenting cells provide co-stimulatory signals through CD28 to T-cells, an inhibitor of CD28-B7.1/B7.2 binding has been proposed as a therapeutic agent for suppression of excessive T-cell activity. Although anti-B7.1/B7.2 antibodies are known to block B7.1 and B7.2 molecules, their effects on intracellular events in antigen presenting cells remain unclear. In this study, anti-B7.1/B7.2 antibodies decreased secretion of nitric oxide and pro-inflammatory cytokines such as TNF-$\alpha$, IL-$1{\beta}$, and IL-12 in LPS-activated RAW264.7 macrophage-like cells and peritoneal macrophages. Moreover, anti-B7.1/B7.2 antibodies inhibited $I{\kappa}B{\alpha}$ phosphorylation and down-regulated expression of co-stimulatory molecules including B7.1, B7.2, and PD-L1 in LPS-stimulated peritoneal macrophages. These findings suggest that CTLA4-Ig and anti-B7.1/B7.2 antibodies may be candidates to treat chronic inflammatory diseases and autoimmune responses caused by excessive activation of both T-cells and macrophages.

Rapid Detection of Salmonella spp. by Antibody-Immobilized Piezoelectric Crystal Biosensor (고정화법을 달리하여 제조한 압전류적 항체 센서에 의한 Salmonella spp.의 신속 검출)

  • 박인선;김우연;김남수
    • Journal of Food Hygiene and Safety
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    • v.13 no.3
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    • pp.206-212
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    • 1998
  • An improved antibody-coated sensor system based on quartz crystal microbalance was developed for the detection of Salmonella spp. An antibody against Salmonella common structural antigen was immobilized onto one gold electrode of the piezoelectric quartz crystal surface by various immobilization procedures. The best results in sensitivity and stability were obtained with the thin layers of protein A and 3,3'-dithiopropionimidate.2HCI(DTBP), a homobifunctional thiol-cleavable crosslinker. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency owing to S. typhimurium adsorption decreased conspicuously. The antibody-immobilized crystals prepared by the gold-protein A complex formation and DTBP thiolation showed the frequency shifts of 80 and 283 Hz, respectively. The time required for maximum frequency shift was about 30~60 min. The antibody-coated crystal could be reused for 6~8 consecutive assays.

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Increased Refolding Yield of Disulfide Bond Bridged Fab-Toxin Homodimers by the Insertion of CH3 Domains

  • Song Jeong-Wha;Won Jae-Seon;Lee Yong-Chan;Choe Mu-Hyeon
    • Journal of Microbiology and Biotechnology
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    • v.16 no.7
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    • pp.1104-1110
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    • 2006
  • Recombinant antibody-toxin is a bifunctional protein that binds and kills a target cell expressing a specific antigen on the surface of the cell, and its structure is chimeric, in which a toxin is fused to an antigen-binding domain such as scFv or Fab. Divalent antibody-toxin molecules showed higher cytotoxicities against cancer cell lines than monovalent molecules. However, the yields of the divalent molecules were very low. In this study, we introduced the CH2, CH3, or CH2-CH3 (=Fc) domain of antibody in the middle of the Fab-toxin between the hinge region of human IgG1 and the toxin domain to increase the yield. The covalently bonded dimer could be formed by three disulfide bridges from cysteine residues in the hinge region. The molecule with the CH3 domain showed about 3-fold higher dimerization yield than previously constructed Fab-toxin molecules, while maintaining the cytotoxic activity comparable to that of scFv-toxin. However, the introduction of CH2 or Fc domain to the same position showed little effect on the dimerization yield. We also observed that the introduction of the CH3 region made it possible to form noncovalently associated dimer molecules.

Immunomodulatory Activity of Ginsan, a Polysaccharide of Panax Ginseng, on Dendritic Cells

  • Kim, Mi-Hyoung;Byon, Yun-Young;Ko, Eun-Ju;Song, Jie-Young;Yun, Yeon-Sook;Shin, Taek-Yun;Joo, Hong-Gu
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.3
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    • pp.169-173
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    • 2009
  • Ginsan, a Panax ginseng polysaccharide that contains glucopyranoside and fructofuranoside, has immunomodulatory effects. Although several biologic studies of ginsan have been performed, its effects on dendritic cells (DCs), which are antigen-presenting cells of the immune system, have not been studied. We investigated the immunomodulatory effects of ginsan on DCs. Ginsan had little effect on DC viability, even when used at high concentrations. Ginsan markedly increased the levels of production by DCs of IL-12 and TNF-${\alpha}$, as measured by ELISA. To examine the maturation-inducing activity of ginsan, we measured the surface expression levels of the maturation markers MHC class II and CD86 (B7.2) on DCs. It is interesting that ginsan profoundly enhanced the expression of CD86 on DC surfaces, whereas it increased that of MHC class II only marginally. In $^3H$-thymidine incorporation assays, ginsan-treated DCs stimulated significantly higher proliferation of allogeneic $CD4^+$ T lymphocytes than did medium-treated DCs. Taken together, our data demonstrate that ginsan stimulates DCs by inducing maturation. Because DCs are critical antigen-presenting cells in immune responses, this study provides valuable information on the activities of ginsan.