• Journal of Biosystems Engineering
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• 제38권4호
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• pp.335-340
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• 2013

Purpose: This study was performed to develop a lateral flow strip sensor for the detection of pathogenic Escherichia coli O157:H7 in various samples. Also, feasibility of using an image analysis method to improve the interpretation of the strip sensor was evaluated. Methods: The lateral flow strip sensor has been fabricated based on nitrocellulose lateral-flow membrane. Colloidal gold and E. coli O157:H7 antibodies were used as a tag and a receptor, respectively. Manually spotted E. coli O157:H7 antibody and anti-mouse antibody on nitrocellulose membrane were used as test and control dots, respectively. Feasibility of the lateral flow strip sensor to detect E. coli O157:H7 were evaluated with serially diluted E. coli O157:H7 cells in PBS or food samples. Test results of the lateral flow strip sensor were measured with an image analysis method. Results: The intensity of the test dot started to increase with higher concentration of the cells were introduced. The sensitivities of the sensor were both $10^4$ CFU/mL Escherichia coli O157:H7 spiked in PBS and in chicken meat extract, respectively. Conclusions: The lateral flow strip sensor and image analysis method could detect E. coli O157:H7 in 20 min, which is significantly quicker than conventional plate counting method.

• Journal of Microbiology and Biotechnology
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• 제26권8호
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• pp.1457-1463
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• 2016

Vibrio anguillarum, a devastating pathogen causing vibriosis among marine fish, is prevailing in worldwide fishery industries and accounts for grievous economic losses. Therefore, a rapid on-site detection and diagnostic technique for this pathogen is in urgent need. In this study, two mouse monoclonal antibodies (MAbs) against V. anguillarum, 6B3-C5 and 8G3-B5, were generated by using hybridoma technology and their isotypes were characterized. MAb 6B3-C5 was chosen as the detector antibody and conjugated with quantum dots. Based on MAb 6B3-C5 labeled with quantum dots, a modified dot blot assay was developed for the on-site determination of V. anguillarum. It was found that the method had no cross-reactivity with other than V. anguillarum bacteria. The detection limit (LOD) for V. anguillarum was 1 × 10³ CFU/ml in cultured bacterial suspension samples, which was a 100-fold higher sensitivity than the reported colloidal gold immunochromatographic test strip. When V. anguillarum was mixed with turbot tissue homogenates, the LOD was 1 × 10³ CFU/ml, suggesting that tissue homogenates did not influence the detection capabilities. Preenrichment with the tissue homogenates for 12 h could raise the LOD up to 1 × 10² CFU/ml, confirming the reliability of the method.

• 대한핵의학회지
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• 제16권1호
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• pp.63-72
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• 1982

Hepatoscintigram has been a useful diagnostic method for the liver diseases since 1953, but reasonable diagnostic criteria for parenchymal liver diseases are not yet accurately established. For the purpose of searching for more advanced diagnostic criteria for various types of live disease by the liver scan, a retrospective study was made of 272 cases who underwent both hepatoscintigram with 198 Au colloid and liver biopsy in Hanynag University Hospital from Jan., 1978 to Dec., 1981. The results were as follows: 1. Fuzzy margin (irregular indentation of the liver margin) in the hepatoscintigram was noted in 226 cases (97.79%). 2. Of 35 cases with fuzzy margin only, 28 cases (80%) revealed mild parenchymal liver disease, such as acute hepatitis or chronic persistent hepatitis by the liver biopsy. 3. Mottling change (209 cases) was always accompanied by fuzzy margin except only one case, and 31 cases (86.1%) of fuzzy and mottling cases (36 cases) showed mild parenchymal liver disease. 4. Configuration change (193 cases) was usually accompanied with other changes and espicially 104 cases had configuration change with fuzzy and mottling changes. 73 cases (88.44%) of 86 cases with severe configuration change revealed advanced parenchymal liver disease on biopsy. If liver scan showed mild configuration change, we could not decide the type of liver disease only liver scan, and so further studies are needed. 5. Splenic uptake was noted in 34 cases (40.48%) of 84 cases with advanced parenchymal liver disease, and the degree of splenic uptake was for the most part morderate or severe; whereas splenic uptake was noted in 18 cases (16.51%) of the mild parenchymal liver disease (109 cases), and the degree of splenic uptake was largely mild.

• Parasites, Hosts and Diseases
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• 제57권3호
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• pp.283-290
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• 2019

A rapid diagnostic test (RDT) kit was developed to detect non-structural protein 1 (NS1) of yellow fever virus (YFV) using monoclonal antibody. NS1 protein was purified from the cultured YFV and used to immunize mice. Monoclonal antibody to NS1 was selected and conjugated with colloidal gold to produce the YFV NS1 RDT kit. The YFV RDTs were evaluated for sensitivity and specificity using positive and negative samples of monkeys from Brazil and negative human blood samples from Korea. Among monoclonal antibodies, clones 3A11 and 3B7 proved most sensitive, and used for YFV RDT kit. Diagnostic accuracy of YFV RDT was fairly high; Sensitivity was 0.0% and specificity was 100% against Dengue viruses type 2 and 3, Zika, Chikungunya and Mayaro viruses. This YFV RDT kit could be employed as a test of choice for point-of-care diagnosis and large scale surveys of YFV infection under clinical or field conditions in endemic areas and on the globe.

• Journal of Microbiology and Biotechnology
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• 제17권7호
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• pp.1152-1161
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• 2007

An immunochromatography (ICG) strip test based on a monoclonal antibody for the rapid detection of L. monocytogenes in meat and processed-meat samples was developed in this study. A monoclonal antibody (MAb) specific to L. monocytogenes was produced from cloned hybridoma cells (FKLM-3B12-37) and used to develop an ICG strip test. The antibody showed a stronger binding to L. monocytogenes than other Listeria species, and a weak cross-reaction to S. aureus based on an ELISA. The detection limit of the ICG strip test was $10^5\;cell/ml$. In total, 116 meat and processed-meat samples were collected and analyzed using both the ICG strip test and a PCR. The ICG strip test and PCR indicated L. monocytogenes contamination in 34 and 27 meat samples, respectively. The 7 meat samples not identified as L. monocytogenes positive by the PCR were also tested using an API kit and found to be contaminated by Listeria species. In conclusion, the ICG strip test results agreed well with those obtained using the PCR and API kit. Thus, the developed ICG has potential use as a primary screening tool for L. monocytogenes in various foods and agricultural products, generating results within 20 min without complicated steps.

• 한국수산과학회지
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• 제48권2호
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• pp.158-167
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• 2015

A lateral flow immunoassay kit based on antigen-antibody interactions was developed to detect residues of beta-lactams, quinolones, tetracyclines, and sulfonamides in farmed fish. Group-specific antibodies showing cross-reactivity with other antibiotics in the same group were produced in rabbits. The rabbits were immunized eight times to obtain the maximum titers. Antibodies were extracted from the antisera collected from the immunized rabbits and produced group-specific reactions with antibiotics from the four groups. A kit was prepared that optimize conditions for the antigen-antibody reaction, using colloidal gold conjugated antibodies, and was designed to detect the four groups of antibiotics simultaneously. The kit enabled the detection of antibiotics in the four groups at below maximum residue limits (MRLs), which were $200{\mu}g/kg$ for tetracyclines, $100{\mu}g/kg$ for sulfonamides, $50{\mu}g/kg$ for beta-lactams, and $100{\mu}g/kg$ for quinolones. The cross-reactivity of the antibodies ranged from 10-80% for the sulfonamides, 20-100% for tetracyclines, 38-100% for quinolones, and 20-100% for the beta-lactams, confirming that the antibodies were group specific. The test kit was used 30 times to examine spiked antibiotics at the limits of detection (LODs) and all produced positive results, indicating high sensitivity. The LODs for the assay ranged from 4-20 ng/mL for beta-lactams, 25-50 ng/mL for sulfonamides, 20-100 ng/mL for tetracyclines, and 30-80 ng/mL for quinolones, and there were no false negative reactions at above these LODs. In addition, all of the LODs of the developed kit were correlated with high-performance liquid chromatography (HPLC) data. Our lateral flow immunoassay kit can simultaneously detect antibiotic residues from a large number of fish samples rapidly, strengthening the safety of domestic farmed and imported fish.

• 대한수의학회지
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• 제39권2호
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• pp.247-256
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• 1999

A disease of young Holstein calves characterized by recurrent pneumonia, ulcerative and granulomatous stomatitis, enteritis with bacterial overgrowth, periodontitis, delayed wound healing, persistent neutrophilia and death at an early age had been originally described in 1983 and again in 1987. Most of these calves had stunted growth and a persistent, progressive neutrophilia (often exceeding 100,000/ml). By investigation of pedigrees, all of the affected calves have now been traced to a common sire and confirmed by polymerase chain reaction (PCR) diagnostic DNA testing to be homozygous carriers of a defective allele for bovine CD18. Neutrophils from these calves have several functional deficits and, most importantly, fail to adhere in a ${\beta}_2$-integrin dependent manner. The ${\beta}_2$-integrins represent a family of glycoproteins which participate in various leukocyte adhesion reactions during host defense. The presence or absence of ${\beta}_2$-integrin molecules can be demonstrated on the surface of neutrophils, monocytes and lymphocytes from normal or affected calves using specific monoclonal antibodies and flow cytometry, or by colloidal gold immunolabeling and scanning electron microscopy in backscatter mode. Deficiency of the ${\beta}_2$-integrins on all leukocyte types in Holstein calves is analogous to leukocyte adhesion deficiency (LAD) seen in humans. Neutrophils in bovine (BLAD) and human LAD patients are unable to adhere to the endothelial lining of the cardiovascular system thus interrupting egression of neutrophils into infected tissues. Other leukocytes, while still deficient in expression of the ${\beta}_2$-integrins, are still able to efficiently egress from the blood stream due to interactions of other adhesion molecules that are not as highly expressed on neutrophils. Both BLAD cattle and LAD children (who do not receive bone marrow transplants) often die at an early age as a result of the failure of neutrophils to extravasate into infected tissues. In 1991, Shuster, et $al^{27}$, identified two point mutations within the alleles encoding bovine CD18 in a Holstein calf afflicted with leukocyte adhesion deficiency. One mutation causes an aspartic acid to glycine substitution at amino acid 128 (D128G) in an extracellular region of this adhesion glycoprotein that is highly conserved (> 95% identity) between humans, cattle and mice. The other mutation is silent. Numerous calves with clinical symptoms of leukocyte adhesion deficiency have since been tested and all have been found homozygous for the D128G allele. In addition, calves homozygous far the D128G allele have been identified during widespread DNA testing in the United States. All cattle with the mutant allele are related to one bull, who through artificial insemination (A.I.), sired many calves in the 1950's and 1960's. The carrier frequency of the D128G CD18 allele among U.S. Holstein cattle had reached approximately 15% among active A.I. bulls and 8% among cows. By 1993, the organization of the dairy industry and the diagnostic test developed to genotype cattle, enabled virtually complete eradication of bovine leukocyte adhesion deficiency among current and future A.I. bulls.

• Applied Microscopy
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• 제30권2호
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• pp.173-183
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• 2000

사람 무릎관절 윤활막을 구성하는 윤활세포 중 윤활포식세포(phagocytic synovial cell, type A cell)의 기원에 대한 논의는 형태적으로 큰포식세포의 모습을 하고 있는 단핵포식체 계 (mononuclear phagocyte system)의 한 일부로서 아마도 골수(bone marrow)에서 기원되어졌을 것이라고 알려져 있다. 기능적으로도 LCA, HLA-DR과 Ia 항원에 양성반응을 보여 큰포식세포의 일부로 알려졌으나 아직 연구가 부족한 실정이다. 본 연구는 CD14와 활성화된 큰포식세포의 표지물로 알려진 CD105(endoglin)를 이용하여 윤활포식세포의 세포 내 발현부위를 규명하고, 기능적으로 활성화된 큰포식세포와 포식작용의 역할을 수행하는지 여부를 확인하기 위해 사람의 무릎관절에서 윤활세포들을 냉동초미세박절법을 이용한 면역조직화학 기법으로 CD14와 CB105에 대한 금표지를 하여 투과전자현미경으로 관찰한 결과 다음과 같은 결론을 얻었다. 1. CD14는 윤활포식세포의 과립세포질세망과 세포질및 가장자리, 공포 주변 부위에서 표지 되었으며 공포내에서는 표지 되지 많았다. 2. CD105(endoglin)는 윤활포식세포의 세포막 가장자리와 세포질 돌기를 따라 표지 되었으며 공포 주변 부위에서도 표지 되었으나, 공포 내에서는 표지 되지 많았다. 이상의 결과로 보아 사람 무릎관절 윤활세포층에 위치하는 윤활포식세포는 CD14와 CD105의 항원에 대한 표지를 보이므로 활성화된 큰포식세포나 포식작용의 역할을 수행하는 것으로 생각된다.