• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.176-182
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• 2006

Sensitive and specific monoclonal antibody (MAb) was produced from hybridoma (1H11-5) obtained by fusion of myeloma cell (V653) and spleen cell isolated from mouse immunized sulfamthazine (SMZ)-HG-KLH. Direct competitive ELISA was developed for rapid detection of SMZ in milk samples using MAb against SMZ with optimized conditions between MAb and SMZ-HG-HRP conjugate, and applicable conditions for analysis of milk samples were established. Detection range of immunoassay was 0.1 to 100 ppb. Recoveries from spiked raw milk and processed milk samples averaged 82.1-120.7 and 82.1-97.1%, respectively.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.314-318
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• 1998

An establishment of effective control measures to PRRSV infection in swine industry depends on a sensitive and specific diagnosis to detect either viral antigen and/or antibodies to PRRSV. Several diagnostic methods are available to detect antibodies against PRRSV, including IPMA, IFA and ELISA tests have been successfully developed. Sensitivity of the indirect immunofluorescent assay in MA-104 cells using Korean field isolate PL96-1 was superior to that of VR-2332 and field isolate PL96-2. Sensitivity and specificity of the IFA test with PL96-1 were comparable to those of commercial ELISA test kit but ELISA test was more sensitive for the detection of declining antibodies to PRRSV in finishing pigs. In this study we concluded that IFA and ELISA test could be utilized to detect antibodies to PRRSV and the results generated from these two tests were comparable and there were no significant difference between these two tests.

• Korean Journal of Veterinary Service
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• v.37 no.3
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• pp.151-156
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• 2014

Porcine reproductive and respiratory syndrome virus (PRRSV) causes major economic losses to the Korean pig industry. ELISA tests using recombinant nucleocapsid protein of PRRSV have been most commonly used for PRRS diagnostics. In the current study, two commercial PRRSV ELISA kits (Bionote PRRSV Antibody ELISA and IDEXX 3XR PRRS Antibody ELISA) have been compared using sera collected from 19 swine farms in various stages of PRRSV infection confirmed by professional diagnostic centers. Thus 130 sera collected from 5 different farms with active PRRSV infection, 130 sera from 6 different farms with PRRS-stabilized status, and 140 sera from 8 different farms with PRRS-free status were evaluated to determine the correlation of test results between those ELISA kits. Both ELISA kits showed a good correlation [PRRSV-positive farms ($R^2$=0.6375) and stabilized farms ($R^2$=0.8928)] in sample-to-positive (S/P) ratio va lues. Among the 140 sera from negative farms, one sample was falsely positive by either of the ELISA kits. In conclusion, both of the ELISA kits showed a good correlation when applied on field samples collected from farms at various stages of PRRSV infection. Bionote ELISA or IDEXX ELISA gave a false positive result on 1 out of 140 negative samples so their specificity was calculated as 99.3%. Therefore, Bionote ELISA would be a good complementary and alternative method for IDEXX ELISA kit, and vice versa.

• The Journal of Korean Society of Virology
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• v.28 no.1
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• pp.31-38
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• 1998

In Korea, all domestic made test systems for detecting antibodies in HIV-1 contain the antigens from human immunodeficiency type 1 (HIV-1) subtype B. However, because HIV-1 subtype O is significantly different in amino acid sequences from all other subtypes of HIV-1, there has been a need for developing a test for detecting antibodies in subtype O. For this purpose, the entire nucleotide sequence corresponding to the extracellular domain of the transmembrane glycoprotein of HIV-1 subtype O was synthesized with consideration of Escherichia coli condon usage. Various regions of the extracellular domain were cloned into E. coli expression vectors and tested for levels of protein production. The nucleotide sequence, named ECTM, that can encode a 129 amino acid-long peptide, was found to be expressed at a high level in E. coli. The protein of approximately 17 kDa specifically reacted with sera from individuals infected with HIV-1 subtype O. The ECTM protein was purified to near homogeneity by the CM-T gel chromatography, using concentrated, denatured inclusion bodies. In Western blot analysis, the purified viral antigen reacted with sera from individuals infected with subtype O more efficiently than subtype B. The enzyme linked immunoabsorbent assay (ELISA) system was developed using the subtype O viral protein and compared with the commercially available kit lacking the antigens from subtype O. The ELISA kit containing the subtype O antigen ECTM alone efficiently reacted with sera from individuals infected with subtype O. The subtype O antigen-containing kit produced a positive absorbence even when sera were diluted 512-fold, suggesting a high sensitivity. The commercially available kit also reacted with subtype O sera, but produced a negative result at a dilution of 8-fold. Our results suggest that the currently available kit may not be able to efficiently detect subtype O sera and that the viral protein developed in this study may be added to the current system to maximize the detection of sera from individuals infected with subtype O.

• Journal of fish pathology
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• v.17 no.1
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• pp.11-20
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• 2004

The present study compared purification methods of hen egg yolk immunoglobulin (IgY) from the hen immunized with Edwardsiella tarda. The purification of anti-E. tarda IgY was performed by four different methods, polyethylene glycol (PEG), chloroform polyethylene glycol (Chloroform-PEG), ammonium sulfate and purification kit. Purified IgY had heavy chain of 64 kDa and light chain of 27 kDa size. IgY purified from the hen immunized with E. tarda showed higher ELISA values and agglutination titers than those with IgY purified from the non-immunized hen as a negative control. In addition, purified IgY recognized similar E. tarda proteins to those with anti-E. tarda rabbit serum by western blotting. Purified IgY had an agglutination titer of 1:512 by PEG method and ammonium sulfate method, and 1:128 by chloroform-PEG method and purification kit. Moreover, PEG method was the most rapid method among the four different IgY purification methods. These results indicate that PEG method is effective purification method maintaining biological activity of the IgY.

• Korean Journal of Veterinary Service
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• v.24 no.1
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• pp.21-29
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• 2001

To compare of serum antibody titers using ELISA and HI, serum samples were collected from 100 breeders and their progeny 550 broilers. The breeders and broilers were vaccinated with infectious bronchitis(IB)- and Newcastle disease(ND)-viruses according to general vaccination program. The antibodies in serum samples against IB and ND viruses were detected by enzyme-linked immunosorbent assay(ELISA) using commercial ELISA kit and hemagglutination inhibition(HI) test. Geometric mean titer(GMT) of ELISA and In titers were monitored from 1-day-old to 35-day-old broilers and compared to those of breeder chickens. The antibody titers of breeders vaccinated with ]B virus showed 47,800, ELISA and 7.2, HI, respectively. Progeny chicks, 1-day-old, vaccinated with IBV showed high antibody titers than those of breed chickens. Those chicks were maintained protective antibody levels until 11-day-old. From 14-day-old, the antibody level decreased below protective levels. In ND, breeders serum antibody titers ELISA and Eiu were 30,200 GMT and 8.7 HI titer, respectively. On 1-day-old chicks, antibody levels was decreased to half in ELISA(16,270) compared with those of breeders, but In titers was 7.4. Progeny broilers, protective antibody level was maintained until 14- day-old by ELISA, but at 11-day-old by HI titers. After then, ND antibody titer was continuously decreased underdefense level. These result indicated that the ELISA method be more sensitive than HI titration to detect serum antibody level for IBV and NDV.

• Korean Journal of Veterinary Service
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• v.35 no.4
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• pp.333-337
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• 2012

This study was carried out to investigate the prevalence of bovine leukemia virus (BLV) infection and to compare the results of enzyme-linked immunosorbent assay (ELISA) and nested polymerase chain reaction (nPCR) in dairy farms in northern Gyeonggi province from August through December 2011. A total of 625 dairy cattle from 14 dairy farms were tested for antibodies against BLV using commercially available ELISA test kit. The overall seroprevalence of BLV infection was 76.3%. The seroprevalence of diary cattle according to age was the highest at 61~72 months (88.0%, P<0.001). Two hundred fifty one dairy cattle from 7 diary farms were tested ELISA and nPCR. The kappa value of BLV between ELISA and nPCR was 0.765. The results indicate that BLV infection spread widely in dairy farms and the nPCR is rapid method for the early detection of BLV infection.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.297-303
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• 1998

For the extraction and measurement of zearalenone in the corn, bean, wheat and barley contaminated with Fusarium graminearum, the zearalenone-oxime, zearalenone-oxime BSA and zearalenone monoclonal antibodies were studied to develop and apply the direct competitive enzyme linked immunosorbent assay (ELISA). The extraction range of zearalenone with the monoclonal antibodies produced in this experiment was 10ng to 500ng/g feed and the 50% inhibition value was 50ng/ml. The mean recoveries of zearalenone artificially spiked in the ground corn were 89%. The specificity of F-2 monoclonal antibody for the analogues was favorable for the direct competitive ELISA. The result of the experiment showed the zearalenone in the corn, bean, wheat and barely naturally contaminated with the mold would be suitable for extraction and measurement with the monoclonal antibodies.

• Journal of Life Science
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• v.28 no.7
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• pp.835-840
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• 2018

Quantitative determination of the protein expression levels is one of the most important parts in assessment of the safety of foods derived from genetically modified (GM) crops. Overexpression of AtCYP78A7, a gene encoding cytochrome P450 protein, has been reported to improve tolerance to abiotic stress, such as drought and salt stress, in transgenic rice (Oryza sativa L.). In the present study, an enzyme-linked immunosorbent assay (ELISA) kit for diagnosing AtCYP78A7 protein including AtCYP78A7-specific monoclonal antibody was developed. GST-AtCYP78A7 recombinant protein was induced and purified by affinity column. Four monoclonal antibodies (mAb 6A7, mAb 4C2, mAb 11H6, and mAb 7E8) against recombinant protein were also produced and biotinylated with avidin-HRP. After pairing test using GST-AtCYP78A7 protein and lysate of rice samples, mAb 4C2 and mAb 7E8 were selected as a capture antibody and a detecting antibody, respectively, for ELISA kit. Product test using rice samples indicated that percentages of detected protein in total protein were greater than 0.1% in AtCYP78A7-overexpressing transgenic rice (Line 10B-5 and 18A-4), whereas those in negative control non-transgenic rice (Ilpum and Hwayoung) were less than 0.1%. The ELISA kit developed in this study can be useful for the rapid detection and safety assessment of transgenic rice overexpressing AtCYP78A7.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.299-306
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• 2019

Ginseng berry (GB) contains Ginsenoside Re and has anti-inflammatory and anti-wrinkle properties. In this study, TLC fractions 1, 2, and 4 of the ginseng berry amino acid complex were identified and analyzed by HPLC. And identified a peptide (AP-1) by LC/MASS analysis of fraction 1. The anti-inflammatory activity was confirmed by investigating the inhibitory effect of AP-1 on NO production. In addition, collagen synthesis using procollagen type I C-peptide (PIP) ELISA kit was 50% higher effective than that of the control group. From these results, the peptide isolated from ginseng berry amino acid complex is considered to have anti-inflammatory and anti-wrinkle effect, and may be useful as an anti-inflammatory and anti-aging cosmetic raw material.