• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.764-772
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• 1999

To develop an enzyme-linked immunosorbent assay (ELISA) for detecting mold, we produced anti-mold polyclonal antibodies by immunizing extracellular polysaccharide (EPS) of Aspergillus flavus or Penicillium citrinum in rabbits subcutaneously. Using the purified antibody (Ab) and Ab-HRP conjugate, a sandwich ELISA for EPS was established. The standard curve of the ELISA showed the detection limit for P citrinum EPS to be $0.003{\;}\mu\textrm{g}/ml$. The cross-reactivities of the anti-P citrinum EPS Ab toward components of P citrinum such as EPS, liquid, and solid culture mycelium were 100, 10.5, and 0.58%, respectively, and those toward components of A. flavus such as EPS, liquid and solid culture mycelium, and spore were 300, 0.67, 0.29, and 0%, respectively. When the reactivities toward culture broths of 59 mold strains were tested by the sandwich ELISA, most of the Aspergillus (16 of 18) and Penicillium (14 of 16) strains along with one of the two Cladosporium strains gave positive signals in the culture broths even when diluted 1,000 fold, while the rest of species such as Fusarium, Absidia, Alternaria, and Candida gave negative signals. When the water extracts of 30 corn samples were analyzed by the sandwich ELISA, the EPS in the com could be detected in the concentration range of $0.1-1.6{\;}\mu\textrm{g}/g$.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.686-692
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• 2004

To develop the enzyme-linked immunosorbent assay (ELISA) for the analysis of N-acetylehitooligosaccharides (NACOS) and chitooligosaccharides (COS), specific antibodies (Abs) were produced, and their properties were compared. N-acetylehitohexaose (NACOS6), chitohexaose (COS6), and COS mixture (COSM) conjugated to bovine serum albumin (BSA) were used to immunize rabbits. By the use of specific Abs and NACOS6-horseradish peroxidase (HRP), COS6-HRP, and COSM-HRP conjugates, competitive direct ELISA (cdELISA) was developed. The detection limits of NACOS6 by the anti-NACOS6 Ab and COS6 by the anti-COS6 and the anti-COSM Abs in the cdELISAs were about 0.2, 2, ana 2 ng/ml (ppb), respectively. In the cdELISA, the anti-NACOS6 Ab was found to recognize NACOS3-NACOS6, but not N-acetyl-D-glucosamine (GlcNAc), NACOS2, and COSs; the anti-COS6 Ab recognized COS2-COS6 and COSM, but not glucosamine (GlcN) and NACOSs. The recognition pattern of the anti-COSM Ab was almost the same as that of the anti- COS6 Ab, except that the former recognized COS2 and COS3 slightly better than the latter.

• Research in Plant Disease
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• v.16 no.2
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• pp.121-124
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• 2010

Immunocapture reverse transcription polymerase chain reaction (IC-RT-PCR) was applied to the detection of Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), and Zucchini green mottle mosaic virus (ZGMMV) on Cucurbitaceae crops. These seed-borne tobamoviruses were accurately detected from the infected leaves and seeds by IC-RT-PCR. This method was estimated to be about 100 times more sensitive than ELISA, and also it allowed the direct confirmation of ELISA results by using the captured antigens from a completed ELISA microwell. This convenient and reliable method could be used routinely for large-scale field surveys or seed tests of Cucurbitaceae crops.

• Korean Journal of Veterinary Research
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• v.49 no.2
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• pp.121-125
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• 2009

Paratuberculosis caused by Mycobacterium avium subspecies paratuberculosis (Mpt) is a chronic infectious enteric disease with deleterious impact on the performance in ruminants. In Korea, ELISA has been introduced to detect antibodies to Mpt in individual cattle. However, comparison study with ELISA has not been studied until now. In total, a panel of 899 serum samples obtained from dairy cattle was analyzed with two commercial ELISAs for Mpt to assess the performance. Two ELISAs employed in this study were both licensed worldwide. Two ELISAs applied onto same serum samples showed the moderate agreement (kappa value = 0.60). There was non-significant McNemar test (p = 0.0614) between two ELISA results indicating that each proportion detected by two kits did not differ. In addition, the percent agreement between two ELISA results was turned out to be 96.8% which interpreted excellent reproducibility. It was shown from this study that two ELISAs revealed moderate kappa agreement performance. The implication raised is that when ELISAs as diagnostics are used to detect Mpt in individual cattle, positive reaction by either ELISA should be interpreted as serologically Mpt positive due to presumed low sensitivity of ELISAs and their test agreement being less than 100%.

• 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.

• YAKHAK HOEJI
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• v.55 no.1
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• pp.16-21
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• 2011

HER-2 (Human Epidermal Growth Factor Receptor-2) is a protein giving higher aggressiveness in human breast cancers. Trastuzumab is a monoclonal antibody that targets HER-2 and is known to extend survival across all stages of HER2-positive breast cancer. In this study, we attempted to development of a quantitative ELISA (Enzyme-Linked ImmunoSorbent Assay) for evaluating anti HER-2 antibodies using human HER-2 recombinant proteins to support antibody producing processes and pharmacokinetic studies. We established direct or indirect ELISA method for the trastuzumab-like protein combined human recombinant HER-2. The ELISA method will prove to be great value in quantitating anti-HER-2 antibodies levels for developing anticancer antibodies.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.3
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• pp.478-485
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• 2010

The vaccine is biological pretreatment that improves immunity to a particular disease. We can get immunity from producing antibody with injection antigen which has ability to defense against the disease. The ELISA is the most widely used method to measure antibody titer. We have developed and performed validation of ELISA according to the guideline of KFDA and ICH. In this paper, we have verified ELISA method is an excellent method to measure the titer of anti-PA antibody. We have constructed recombinant protective antigen among anthrax toxins and used as antigen of ELISA. In this validation, we have evaluated precision (repeatability, interlaboratory precision), specificity, linearity(range) and LOD, which are validation articles suggested by guideline. Inter-person precision was replaced with inter-laboratory precision. From the results, we have confirmed high precision in all experiments with CV under 20%.

• 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).

• Journal of Food Hygiene and Safety
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• v.29 no.2
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• pp.158-163
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• 2014

In this study, two commercial PCR and ELISA test kits were examined for identification of eight animal species (beef, pork, chicken, duck, turkey, goat, lamb, and horse) from raw meat and meat products in Korea. The detection limit in RAW meat ELISA kit$^{(R)}$ on three types of meat samples blended with beef, pork and chicken, demonstrated that all meat species were differentiable down to 0.2%. RAW meat ELISA kit$^{(R)}$ on animal species resulted in differentiation rate of 94.5% for beef, 93.3% for pork, 90% for lamb, and 100% for chicken, duck, turkey, goat, and horse. In contrast, Powercheck Animal Species ID PCR kit$^{TM}$ resulted in 100% specificity at 0.05% limit of detection for all meat species. The detection limit of Cooked Meat ELISA kit$^{(R)}$ on mixed meat samples heat-treated with different temperatures and times, resulted in 0.1% for all heat-treated mixed meat except for chicken at 1.0%. Additionally, ELISA kit on sixty meat products resulted in specificity of 31.8% for ham, 13.6% for sausages, and 12.5% for ground processed products, and relatively low rate for more than 2 types of mixed meats. On the contrary, meat species differentiation using PCR kit showed higher percentage than that using ELISA kit$^{(R)}$: 50.0% for ham, 41.7% for sausages, and 28.6% for ground processed meat. Futhermore, PCR kit on 54 dried beef meats detected pork genes in 13 products whereas ELISA kit showed negative results for all products. Hence, the possibility of cross-contamination during manufacturing process was investigated, and it was found that identical tumblers, straining trays, cutters and dryers were used in both beef and pork jerky production line, suggesting the inclusion of pork genes in beef products due to cross-contamination. In this study, PCR and ELISA test kits were found to be excellent methods for meat species differentiation in raw meat and heat-processed mixed meat. However, lower differentiation rate demonstrated in case of meat processed products raised the possibility of inclusion of other species due to cross-contamination during manufacturing process.

• Parasites, Hosts and Diseases
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• v.55 no.3
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• pp.247-254
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• 2017

ELISA has been used for the diagnosis of toxoplasmosis, but it is being gradually replaced by a rapid diagnostic test (RDT). We compared and analyzed ELISA and RDT results using the sera collected during 4 consecutive years from residents of Gyodong-do (Island), Incheon-city, Korea. Sera from 921, 993, 940, and 838 adult residents were collected on a yearly basis (2010-2013). ELISA was performed by using a crude extract of T. gondii RH strain antigen and IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), GST-linker-SAG1A, were applied to the sera. Comparison between groups was analyzed by the Student's t-test. The positive seroprevalence surged from 14.7% (135/921, 2010), 23.1% (231/993, 2011), 23.6% (222/940, 2012), and 32.1% (269/838, 2013) by ELISA. In contrast, RDT showed a more moderate increasing trend from 21.7% (200/921, 2010), 25.5% (253/993, 2011), 28.9% (272/940, 2012) and 33.1% (277/838, 2013). Discrepancies between ELISA and RDT were noted near the cut-off value. At the OD 0.15-0.24 range, RDT could detect 16.1% (169/1051) more positives, which suggests an early or acute toxoplasmosis, but at the OD 0.25-0.34 range, ELISA could detect 35.9% (92/256) more positives of possible chronic infections. Over the OD > 0.35 ELISA and RDT agreed in the majority of the cases. This surge in seroprevalence may be caused by the organic agriculture in addition to eating behavior or increase in pets among Koreans. These facts may be applied on a full-scale national survey using RDT to supplement ELISA to define the characteristics of the infection.