• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.4
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• pp.459-465
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• 2015

We tested biomarker systems [enzyme-linked immunosorbent assay (ELISA) and immunochromatography assay (ICG) kits] for the screening of endocrine-disrupting chemicals in contaminated environments using antibodies resulting from $17{\beta}$-Estradiol-induced vitellogenin (Vtg) in the wild scorpion fish Sebastiscus marmoratus. Monoclonal antibodies of two clones (S28 and S15) were used as capture and tracer antibodies for ELISA and ICG assays. ELISA detected Vtg at levels greater than $0.1{\mu}g/mL$, while ICG detected Vtg at levels greater than $1{\mu}g/mL$. However, the ICG system was able to detect antibodies from $17{\beta}$-Estradiol-induced Vtg serum that had been diluted 1,000 times. Our results suggest that previously developed biomarker assays can be used as detection systems to detect known endocrine-disrupting chemicals in contaminated environments, and to measure their activity.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.344-348
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• 1999

A competitive enzyme-linked immunosorbent assay(ELISA) for the detection of antibodies to Treponema pallidum(T.pallidum) was developed and evaluated. T.apllidum lysate was immobilized on the surface of microplate wells and horseradish peroxidase labeled human anti-T.pallidum lysate was immobilized on the surface of microplate wells and horseradish peroxidase labeled human anti-T.pallidum was prepared and used as a tracer. The performance of the competitive ELISA was evaluated by using different specimens. The competitive ELISA showed a sensitivity of 100% in a performance panel consisting of serum and plasma with anti-T.pallidum reactivity ranging from negative to strong positive by FTA-ABS test system and 120 plasma samples positive by TPHA. The specificity of the competitive ELISA was 100% in 1,200 plasma samples collected from healthy seronegative blood donors. These results suggest that the competitive ELISA provides an excellent assay method for the detection of antibodies to T.pallidum, and may be particularly useful for serological blood screening of syphilis.

• Microbiology and Biotechnology Letters
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• v.24 no.5
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• pp.630-635
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• 1996

For a survey of the occurrence of aflatoxin M$_{1}$ (AFM$_{1}$) in domestic cow's milk, we developed an enzyme-linked immunosorbent assay (ELISA) system, and quantitated the toxin in cow's milk. In order to produce specific antibodies AFM, conjugated to bovine serum albumin (AFM$_{1}$-BSA) and Freund's adjuvant were immunized subcutaneously to rabbits. By use of the antiserum showing the highest titer and AFB$_{1}$-HRP conjugate, we established a competitive direct ELISA (cdELISA) for AFM$_{1}$, whose detection limit was 0.003 ppb. The cross-reactivities of the antiserum against aflatoxin M$_{1}$ M$_{2}$, B$_{1}$, B$_{2}$, G$_{1}$, G$_{2}$, B$_{2a}$, and G$_{2a}$, were 100, 29.9, 25.0, 2.7, 13.0, 0.65, 0, and 0%, respectively. When the cdELISA was applied to the cow's milk spiked with AFM$_{1}$ and followed by cleanup with C$_{18}$ cartridge, the mean recovery of the assay was 104% (mean of CV, 6.4%) in the final concentration of 0.01-1 ppb (10-1, 000 ppt). When cow's milk samples gathered from markets and farms were assayed by the cdELISA, the mean concentration and SD of AFM$_{1}$ was 80.4 $\pm$ 55.0 ppt (n=64; range, 5.6-280 ppt).

• Microbiology and Biotechnology Letters
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• v.16 no.3
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• pp.226-230
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• 1988

Antibody against cellobiohydrolase purified from Trichoderma viride had been obtained by injection to rabbit. The antibody had a high specificity against the cellobiohydroase evidienced by absence of immunological reaction to other isozymes from Trichoderma viride. Assay limit of cellobiohydrolase was 1-10 $\mu\textrm{g}$ by column single immunodiffusion and by enzyme linked immunosorbent assay, it was 10-140 ng and 100-1200 pg when the dilution of antibody was 10$^{-6}$ and 10$^{-5}$, respectively.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.253-259
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• 1998

In this study, we developed immunoassay methods for the more convenient and effective detection of rat tracheal mucin and the results were compared with those of [$3^H$]glucosamine based gel-filtratioh method. A monoclonal anti-rat tracheal mucin antibody, mAbRT03, which specifically recognizes rat tracheal mucins, was used throughout in this study. To induce mucin secretion, varying concentrations of ATP (0-2 mM) were applied to the primary rat tracheal surface epithelial (RTSE) cell culture which had been metabolically radiolabeled with [$3^H$]glucosamine and the secretion of mucin was analyzed both by the immunoassay and the gel-filtration chromatography methods. For the immunoassay, the following two procedures were employed. 1) Simple ELISA; the culture spent media were directly coated onto the assay plate and the immunoreactivity with mAbRT03 was assessed from the standard curve generated with the purified rat mucin. 2) Inhibition ELISA; A known amount of the purified rat mucin was coated onto the assay plate and then ATP-stimulated culture spent media were added to inhibit the immunorelitivity with mAbRT03. The contents of mucin in the sample were calculated from the standard inhibition curve which was generated with the purified rat mucin. The assay results obtained from the immunoassays were identical with those from the gel-filtration methods. The present result indicates that ELISA can be substituted for the laborious, time-consuming gel-filtration assay in studying the regulation of airway mucin release from cultured airway epithelial cells.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.953-958
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• 1996

A simple and rapid ELISA (enzyme-linked immunosorbent assay) system for fumonisins, a group of potentent carcinogen, was developed. To produce anti-fumonisin B1 (FB1) antibodies, FB1 conjugated to keyhole lympet hemocyanin (KLH) and Freund's adjuvant were immunized into rabbits subcutaneously 3 times. From one of the antisera showing high titer and good competition with the toxin in ELISA, polyclonal antibodies were purified. The cross-reactivities of the antibodies against fumonisin $B_1,\;B_2\;and\;B_3$ were 100%, 69%, and 166%, respectively. When competitive direct ELISA established by use of the antibody was applied to the spike test of $FB_1$ onto uncontaminated corns, the assay recovery was unstable unless 75% methanol extracts of corn were diluted to 1/100 with buffer. In that condition the mean ELISA recovery of FB1 from corns spiked $1-30\;{\mu}g/g$ was 67% and stable (coefficient of variation (CV) of each recovery percentage, 3.4%). The results suggest that the ELISA system established in this study needs no cleanup procedure and therefore would be powerful to screen a large number of corn samples contaminated with fumonisins.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1184-1187
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• 1996

A simple and rapid detection system for $aflatoxin\;M_1\;(AFM_1)$ in cow's milk by an enzyme-linked immunosorbent assay (ELISA) was developed. Specific antibodies against $AFM_1$, conjugated to bovine serum albumin $(AFM_1-BSA)$ were raised in rabbits and purified. The cross-reactivities of the antibodies against aflatoxin analogs were less than 29.9%. When a competitive direct ELISA (cdELISA) for $AFM_1$, established by use of the antibodies was applied to the spike test of $AFM_1$ onto uncontaminated cow's milk, the assay recovery was unstable unless cow's milk was diluted to 40% (2:3) with phosphate buffered saline (PBS). In that condition of sample dilution, the mean ELISA recovery of $AFM_1$, from the cow's milk was 113% (coefficient of variation (CV) of each recovery percentage, 8.2%) in the range of $0.3{\sim}3.0\;ppb$. These results showed that the ELISA system could be a convenient tool to monitor the contamination of AFM1 more than 0.5 ppb in cow's milk (FDA allowance limit) easily.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.265-269
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• 1983

A comparison was made of a new serological method, thin layer immunoassay (TIA), and an established method, enzyme-linked immunosorbent assay (ELISA), in the detection and quantiacation of antibodies in clonorchiasis. Saline extract of Iyophilized Clonorchis sinensis adult worm was used as antigen, and TIA by the method of Elwing et at. (1976) and ELISA by Voller et at. (1974) were performed. Using sera from known clonorchiasis cases,100% of the sera tested were Positive by TIA and 88.35 by ELISA. TIA produced false positive results in 14 out of 36 cases, which were 10 amoebiasis cases, 16 paragonimiasis cases and 10 healthy controls. ELISA. however, produced a small number of false positives, 7 out of 55 cases. There was correlation between Immunoglobulin G level in sera and ELISA value (correlation coefficient, 0.69), whereas no correlation between Immunoglobulin G level and TIA result. The Performance of TIA and ELISA was not correlated in the results using homologous antigen.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.569-574
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• 2005

Enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to reticuloendotheliosis virus (REV) at single serum dilution was standardized. REV HI, one of the Korean field isolates, was inoculated into chicken embryo fibroblast (CEF) cells and was harvested from the culture fluids and cells after 10 to 12 days. Viruses were purified by centrifugation at the $107,000{\times}g$ for 12 hours on 20, 30, 45% (W/V) sucrose gradient. Virus specific fraction was collected and used as ELISA antigen. To standardize ELISA, the optimal concentration of coating antigen ($1{\mu}g/well$) and conjugate (1/1000) was determined by corrected OD (OD value of positive serum-OD value of negative serum) and P/N ratio (OD value of positive serum/OD value of negative serum). To calculate ELISA titer by measuring absorbance at 1/400 single serum dilution, serum titrations were carried out for various sample sera together with standard positive and negative sera. The observed titers of serum samples were plotted against sample/positive (s/p) ratios at 1/400 serum dilution. From the above data, the ELISA titers could be calculated by the equation of $log_{10}$ ELISA titer = 2.2763 ($log_{10}$ s/p) + 3.482 (r = 0.93). For evaluating the sensitivity, the standardized method were compared with conventional agar gel immunodiffusion (AGID) test method using serum samples collected from REV infected field chicken flocks. Fifty seven of 60 samples (95%) were positive for REV by ELISA, whereas only 11 (18.3%) samples were positive by AGID test. This results suggested that the ELISA tests developed in this study could be used for detection of antibodies to REV with high sensitivity.

• The Plant Pathology Journal
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• v.17 no.1
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• pp.62-66
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• 2001

Detection of Xanthomonas axonopodis pv. citri (Xac) on citrus fruits for exporting is usually made by bacteriophage test (BPT) to demonstrate the pathogen-free status. BPT has rather time-consuming and complicate procedures for dealing with massive samples to be inspected. In this study, enzyme-linked immunosorbent assay (ELISA) was applied to detect Xac on fruits, and compared with BPT. In ELISA, positive reactions occurred in the bacterial densities of $3\times10^5$ cells/ml or more. To detect the bacterial infection on citrus fruits with a density of lower than $3\times10^5$ cells/ml, the bacterial suspensions were mixed with fruit rinse water and incubated in broth medium. Ordinary peptone sucrose broth (PSB) was not a proper medium for increasing Xac density specifically enough to be detect by ELISA. On the other hand, modified PSB (MPSP) amended with Fe-EDTA (0.25 g/$\ell$) and 2.5% potato-dextrose broth sufficed to differentiate uninfected and infected citrus fruits by ELISA after 24 h incubation of the fruit rinse water. Using various citrus samples from infected and uninfected fields, efficiencies in detecting Xac on fruits were compared between ELISA and BPT. For infected fruits samples, ELISA detected Xac by 100%, while BPT by about 44%, indicating that the detection efficiency was improved by 23.5% by ELISA, compared to BPT. In addition, ELISA has simpler procedures for testing and is less time-consuming than BPT, suggesting that ELISA may be accurate and simple method to detect Xac on citrus fruits.