• YAKHAK HOEJI
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• v.41 no.1
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• pp.74-80
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• 1997

A polygonal antibody against recombinant hirudin was raised for the development of a ELISA in biological fluids. Recombinant hirudin was conjugated to maleimide activated carrie r protein, KLH and injected to a rabbit. The third booster collection of antiserum was used as primary antibody for the ELISA. The titer for the detection antibody was determined. The direct ELISA could determine the concentration of hirudin in the range of ~10ng/ml. Affinity pulified IgG was obtained and conjugated to horseradish peroxidase. Purified IgG and IgG-HRP could be used as capture and detection antibody, respectively. Although sandwich ELISA would not give the satisfactory results. it could apply for the detection of hirudin level in the range of ~20 ${\mu}$g/ml.

• The Plant Pathology Journal
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• v.32 no.5
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• pp.452-459
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• 2016

The genomic region of Grapevine fanleaf virus (GFLV) encoding the movement protein (MP) was cloned into pET21a and transformed into Escherichia coli strain BL21 (DE3) to express the protein. Induction was made with a wide range of isopropyl-${\beta}$-D-thiogalactopyranoside (IPTG) concentrations (1, 1.5, and 2 mM) each for duration of 4, 6, or 16 h. However, the highest expression level was achieved with 1 mM IPTG for 4 h. Identity of the expressed protein was confirmed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) followed by Western blotting. The expressed 41 kDa protein was purified under denaturing condition by affinity chromatography, reconfirmed by Western blotting and plate-trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA) before being used as a recombinant antigen to raise polyclonal antibodies in rabbits. Purified anti-GFLV MP immunoglobulines (IgGs) and conjugated IgGs detected the expressed MP and GFLV virions in infected grapevines when used in PTA-ELISA, double antibody sandwich-ELISA, and Western blotting. This is the first report on the production of anti-GFLV MP polyclonal antibodies and application for the virus detection.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.3-13
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• 2020

Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium causing serious infections. The P. aeruginosa T3SS is a syringe-like apparatus on the bacterial surface, with 4 effector toxins: ExoS, ExoT, ExoY, and ExoU. Here, we investigated the effect of ExoS and ExoT of the T3SS of P. aeruginosa K strain (PAK). The type three secretion system (T3SS) is a major virulence system of Pseudomonas aeruginosa (P. aeruginosa). The effector protein Exotoxin S (ExoS) produced by P. aeruginosa is secreted into the host cells via the T3SS. For the purpose of screening the inhibitors with regard to ExoS secretion, we developed the sandwich-type enzyme-linked immunosorbent assay (ELISA) system. PAK clinical strains induce proinflammatory cytokine production through the T3SS, and this involves NF-κB activation in pneumonia mouse models. We tried to confirm the role of the NF-κB transcription factor in ExoS- and ExoT-induced pneumonia mouse models. pro-inflammatory cytokines induction in response to ExoS and ExoT infection relied on NF-κB activation. Our findings highlight the roles of natural poduct in inhibiting proinflammatory cytokine expression during ExoS and ExoT exposure in PAK infections, paving the way for a novel therapeutic approach for the treatment of pulmonary infections.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.556-560
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• 2003

It was determined whether the sandwich ELISA using specific anti-CP4 EPSPS polyclonal and monoclonal antibodies, developed in the previous study, could be applied to detect GM soybean or not. The soybeans (47 imported and 20 domestic soybeans) were analyzed by a sandwich ELISA. The results of imported soybeans were divided into two groups which were high contents $(39.1{\pm}13.5\;{\mu}g/g,\;n=33)$ and low contents of CP4 EPSPS $(2.6{\pm}1.2\;{\mu}g/g,\;n=14)$. The ratio of GM in imported soybeans was about 70.2%. One the other hand, the contents of CP4 EPSPS in domestic soybeans was very low $(0.9{\pm}0.5\;{\mu}g/g,\;n=20)$ which determined to be non-GM soybeans. In case of soybean sprouts, the contents of CP4 EPSPS in soybean sprouts were different between GM and non-GM soybean sprout. The CP4 EPSPS in cotyledon of GM soybeans sprout was higher than that in root hair. The contents of CP4 EPSPS in soybeans sprout of domestic soybeans were very low. Thus, it was possible to determine that the soybeans sprout was made of GM or non-GM soybeans. Also, PCR experiment showed that the sandwich ELISA was accurate to distinguish the soybeans to be GM or non-GM. These results showed the sandwich ELISA could determine the soybeans were GM or non-GM, rapidly and simply.

• The Plant Pathology Journal
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• v.17 no.2
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• pp.106-109
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• 2001

A multi-rapid immunofilter paper assay (multi-RIPA) system was prepared for simultaneous diagnosis of three Tobamoviruses, Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), and Zucchini green mottle mosaic virus (ZGMMV) in cucurbitaceous crops. Each of these viruses was specifically detected by the multi-RIPA from cucumber, watermelon, zucchini, and bottle gourd inoculated with the three Tobamoviruses singly or in combination. The three viruses could infect cucumber, watermelon, and bottle gourd ; however, CGMMV could not infect zucchini as the latex-coated CGMMV antibody showed a negative reaction in the multi-RIPA of the virus-infected plant extract. When the minimum detection level of multi-RIPA was compared with that of double antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) using CGMMV, the latter was 10 times more sensitive than the former. The detection limit of the multi-RIPA for the purified CGMMV was 50 ng/ml. In a survey of the threeviruses in cucurbits growing in commercial fields in 1999 and 2000, CGMMV was detected in watermelon and cucumber, and ZGMMV was detected only in zucchini growing in plastic houses at the suburbs of Chonju, Korea. However, KGMMV was not found in the commercially growing cucurbit crops in our study, The results suggest that the multi-RIPA can be a simple, rapid, specific and convenient tool to detect simultaneously the Tobamoviruses.

• Parasites, Hosts and Diseases
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• v.45 no.1 s.141
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• pp.19-26
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• 2007

This study describes the isolation of a Toxocara canis species-specific excretory-secretory(ES) antigen and the development of an enzyme-linked immunosorbent assay(ELISA) based on this antigen. Analysis of the ES antigens of T. canis, Toxocara vitulorum, Ascaris lumbricoides and Necator americanus larval antigen was performed by SDS-PAGE followed by western blotting. A 57 kDa T. canis-specific antibody fraction(TcES-57) was identified by western blotting and labelling with anti-Toxocara antibodies(from experimental rabbits and human patients) and tracing with anti-human or anti-rabbit peroxidase conjugate. No protein fraction of 57 kDa was detected in ES or larval antigens collected from T. canis, T. vitulorum, A. lumbricoides and N. americanus. Using TcES-57, a specific anti-serum was produced in rabbits and a double sandwich ELISA was developed. This test was validated using known seropositive sera from toxocariasis patients, sera from A. lumbricoides or N. americanus patients, and 50 serum samples from cats. These tests revealed that TcES-57 antigen is specific to T. canis infection and does not cross react with sera of other related infections. Thus, ELISA based on TcES-57 antigen was proven to be an effective tool in the diagnosis of toxocariasis and studies on the role of T. canis in the epidemiology of human toxocariasis.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.6
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• pp.699-705
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• 1997

Although it is known that neuronal cell death during development occurs by apoptosis, the mechanisms underlying excitatory amino acid-induced neuronal cell death remain poorly understood. In this study we have examined the mechanism by which L-glutamate, an excitatory amino acid neurotransmitter, induces cell death in PC12 cell lines. To characterize cell death, we employed sandwich enzyme-linked immunosorbent assay(ELISA) method for cellular DNA fragmentation, DNA agarose gel electrophoresis and chromatin staining by acridine orange and ethidium bromide after treating the PC12 cells with L-glutamate. L-Glutamate caused dose-dependent cell death with a maximum at 24 hrs after the treatment. These cellular fragmentation was blocked by pretreatment of MK-801, a noncompetitive N-methyl-D-aspartic acid(NMDA) receptor antagonist, and nerve growth factor(NGF). Analysis of DNA integrity from L-glutamate-treated cells revealed cleavage of DNA into regular sized fragments, a biochemical hallmark of apoptosis. The PC12 cells that were induced to die by L-glutamate treatment exhibited classical chromatin condensation under the light microscopy after acridine orange and ethidium bromide staining. These results suggest that apoptosis is one of the key features that are involved in L-glutamate-induced excitotoxic cell death in PC12 cells, and these cell death are mediated by NMDA receptor and depend on NGF.

• IMMUNE NETWORK
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• v.3 no.1
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• pp.61-68
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• 2003

Background: Fibroblast functions both as a structural element and as a vital immunoregulatory cell. Fibroblasts regulate inflammation through governing of chemokine expression. In order to elucidate the mechanisms by which the expressions of chemokines were regulated, the co-stimulatory effects of Th1 and proinflammatory cytokines were compared using nasal mucosal fibroblasts. Methods: Human nasal mucosa was obtained from surgery for septal deviation and the growth of fibroblasts was established. Fibroblasts from 4th to 6th passage were stimulated with various combinations of cytokines. To inhibit selected signaling pathways, fibroblasts were pretreated with cyclosporin A, wortmannin, staurosporine, and dexamethasone prior to the stimulation with cytokines. The supernatants were collected and chemokines were detected with a sandwich enzyme-linked immunosorbent assay. Results: $TNF-{\alpha}/IFN-{\gamma}$-induced production of RANTES was inhibited by all inhibitors used. MCP-1 was produced constitutively and $TNF-{\alpha}$-induced or $TNF-{\alpha}/IFN-{\gamma}$-induced production of MCP-1 was not inhibited by cyclosporin A or wortmannin, but by stauroporine or dexamethasone. All inhibitors used in this experiment inhibited $TNF-{\alpha}/IFN-{\gamma}$-induced or $IL-1{\beta}/IFN-{\gamma}$-induced production of MCP-2 in nasal mucosal fibroblasts. Although staurosporine or dexamethasone showed strong inhibitory effects, cyclosporin A or wortmannin did not inhibit the production of MCP-3 by $IL-1{\beta}/IFN-{\gamma}$ treatment. Conclusion: Chemokines were strongly induced by stimulation of cytokines in combination and showed different pattern of inhibition by the inhibitors. Therefore, it was assumed that cytokines acted on multiple pathways or on unknown pathways which converged to gene-specific transcription factors.

• 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.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.299-305
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• 2012

Petunia hybrida is commonly used in landscapes and interiors for its attractive flower. Virus-like foliar symptoms, including a mosaic with dark green islands surrounding the veins and chlorosis on the leaf margins, were observed on a petunia plant from Icheon, Gyeonggido, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic petunia by serological testing for the presence of CMV coat protein (CP) with a direct antibody-sandwich-enzyme-linked immunosorbent assay. An agent was mechanically transmitted to indicator plant species including Chenopodium quinoa. Examination of the inoculated plant leaves by RT-PCR analysis and electron microscopy revealed the presence of specifically amplified CP products and spherical virions of approximately 28 nm in diameter, respectively, providing confirmation of a CMV infection. Analysis of CP sequences showed that CMV petunia isolate (CMVYJC) shared 82.5-100% amino acid sequence identity with CPs of representative CMV strains. Phylogenetic analysis of CPs supports that CMV-YJC is a member of CMV subgroup IA (CMV-IA) and has biological properties of CMV-IA on host species. To our knowledge, this is the first report of CMV from P. hybrida in Korea.