• Korean Journal of Veterinary Research
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• v.33 no.1
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• pp.131-135
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• 1993

Enzyme-linked Immuno sorbent Assay (ELISA) for the serological diagnosis of Brucella abortus was developed and compared with plate agglutination test. Cell wall antigen was extracted from Brucella abortus 1119-3 by sonication and with a sodium deoxychlate solution. Optimum protein concentration of coating antigen were $0.4{\mu}g/100{\mu}{\ell}$ protein on each microtiter plate well. Horse radish peroxidase (HRP) labeled protein-G was used as a tracer of reacted antibodies. ELISA confirmed the agreeable results of 40 cases out of 43 cases by plate aggulutination test. ELISA diagnosed positive cases(10 out of 12) and negative cases (1 out of 12) with dubious sera by plate agglutination test. From this results ELISA could be used for the early diagnostic tools of Brucellosis in cattle.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1723-1729
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• 2018

The aim of this work is to investigate the protective efficacy of emodin, an active, naturally-occurring anthraquinone derivative of several traditional Chinese herbs, against Brucella abortus infection in macrophages. Brucella were incubated with different concentrations of emodin and showed that bacterial survival rates were markedly reduced in a dose-dependent manner at increasing incubation time points. Through bacterial infection assay, the highest non-cytotoxic concentration of emodin demonstrated attenuated invasion of Brucella into macrophages, however it did not inhibit the growth of these pathogens within the host cells. On the other hand, emodin effectively decreased the number of bacteria that adhered to host cells, which indicated its potential as an anti-adhesin agent. Furthermore, using immunoblotting and FACS assay for detecting MAPK signaling proteins and F-actin polymerization, respectively, the results showed that the emodin-incubated cells displayed modest reduction in the phosphorylation levels of ERK1/2 and inhibition of F-actin polymerization as compared to control cells. These findings indicate the potential use of emodin as a naturally-occurring alternative method for the prevention of animal brucellosis although this requires confirmation of safe clinical doses.

• Korean Journal of Veterinary Service
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• v.21 no.4
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• pp.451-465
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• 1998

The present study was carried out to investigate the prevalence of brucellosis in Kyungbuk area for the 3 years from 1966 to 1998. Collective milk samples were routinely screened to detect positive farms by using the milk ring test(MRT), and serum agglutination test was performed to detect sero-positive individuals in the MRT positive farms. Attempt were made to isolate the causative organismas from slaughtered sero-positive reactors and some biochemical and polymerase chain reation characters of the isolates were also made to identify the organisms. Seroprevalence to brucellosis in peoples who are close contact with infected dairy herds was also investigated. Brucellosis of dairy cattle was rare before 1997, but has been broken more frequently since early 1998. By the MRT for dairy herds, positive rate was gradually increased every year : 0.6% in 1996, 1.5% in 1997, 3.9% in 1998. Among 262 MRT-positive herds, only 21 herds(8.0%) showed positive brucellosis in serological test. The isolation rates of Brucella sp from tested materials were 51.2% in supramammary glands, 39.5% in milks, and 50.0% in pulmonary Iymphnode, respectively. Isolated strain and biotype were Brucella(B) arbortus biotype 1 in 26 heads, and were B suis biotype 1 in 2 heads. Isolated strain and vaccine strain were very similar in their colony morphology and staining. In drug susceptibility, isolated stains(B abortus) and vaccine strain(B abortus RB-51) were sensitive to ampicillin, gentamycin, kanamycin, neomycin, penicillin, streptomycin, and to tetracycline, but resistant to erythromycin. In the PCR, field strains reacted to BA and IS711 primers, and vaccine strain reacted to BA, IS711, and RB5l primers. In the plate agglutination test of 96 sera of human contacted with animals, serum antibody titer detected 1 : 100 in one person, 1 : 200 in one, and below 1 : 25 in the others.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.89-92
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• 2011

The routine identification and differentiation of Brucella species is a time-consuming and labor-intensive process, which frequently places personnel at risk of laboratory-acquired infection. Here, we describe the development of a rapid multiplex PCR assay for the confirmation of presumptive Brucella isolates. The assay was able to identify and differentiate major human pathogens, namely B. abortus, B. melitensis, and B. suis, in a single test of less than an hour and a half.

• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.567-570
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• 2012

In vitro activities of 13 antibiotics were assessed against 85 Brucella abortus isolates from naturally infected cattle in the Republic of Korea during 1998-2006, using broth microdilution test. Tetracyclines showed the most excellent activity against B. abortus, displaying MIC values of 0.5 ${\mu}g/ml$ or below. In particular, minocycline showed the lowest $MIC_{50/90}$ values (0.125/0.125 ${\mu}g/ml$) in this study. Among four fluoroquinolones tested, ciprofloxacin ($MIC_{50/90}$, 0.5/1 ${\mu}g/ml$) and norfloxacin ($MIC_{50/90}$, 8/8 ${\mu}g/ml$) had the most and the least activities, respectively. Gentamicin ($MIC_{50/90}$, 1/1 ${\mu}g/ml$) was more effective than streptomycin, erythromycin, rifampin, and chloramphenicol ($MIC_{50/90}$, 2/2 ${\mu}g/ml$).

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1885-1891
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• 2017

In this study, we evaluated the inhibitory effect of a rice bran mixture extract (RBE) on Brucella abortus pathogenesis in professional (RAW 264.7) and nonprofessional (HeLa) phagocytes. We fermented the rice bran mixture and then extracted it with 50% ethanol followed by gas chromatography-mass spectrometry to identify the components in RBE. Our results clearly showed that RBE caused a significant reduction in the adherence of B. abortus in both cell lines. Furthermore, analysis of phagocytic signaling proteins by western blot assay revealed that RBE pretreatment resulted in inhibition of phosphorylation of JNK, ERK, and p38, leading to decline of internalization compared with the controls. Additionally, the intensity of F-actin observed by fluorescence microscopy and FACS was remarkably reduced in RBE-pretreated cells compared with control cells. However, the intracellular replication of B. abortus within phagocytes was not affected by RBE. Taken together, these findings suggest that the phagocytic receptor blocking and suppressive effects of RBE on the MAPK-linked phagocytic signaling pathway could negatively affect the invasion of B. abortus into phagocytes.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.67-75
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• 2003

A total of 260 dogs were randomly selected from two different treed kennels that brucellosis has occurred (group 1, 126 dogs), and random selected breed kennel (group 2, 134 dogs), and monitored for Brucella canis (B. canis) by 2-mercaptoethanol rapid slide agglutination test (2ME-RSAT) and bacterial culture method. For the differentiation, PCR-RFLP using omp-31, wbkA and per genes used for 52 of B canis strains (strain I) isolated in this study and 3 of B. canis strains (strain II) isolated in 1994 in Korea. 2ME-RSAT revealed that 63/126 dogs (50.0%) and 12/134 dogs (9.0%) were positive in group I and group II, respectively. Bacterial culture revealed that 47/126 dogs (37.3%) and 5/134 dogs (3.7%) were positive in group I and group II, respectively. As the results of PCR-RFLP, $\underline{omp}-31$ was amplified from all Brucella spp, except B. abortus. All B. canis isolates showed unique PCR-RFLP pattern following digestion with Bmel8I. However, all Brucella spp. showed the same PCR-RFLP pattern following digestion with SalI. PCR-RFLP analysis of wbkA revealed that all Brucella spp. showed the same pattern following digestion with HindIII. PCR-RFLP analysis of per revealed that B. abortus 544 and B. melitensis 63/9 showed the same pattern, but different from B. suis and B. canis following digestion with HindIII.

• Korean Journal of Veterinary Research
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• v.50 no.2
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• pp.117-124
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• 2010

Members of the genus Brucella are facultative intracellular bacteria and cause brucellosis, a chronic disease in humans and abortion in animals. In this study, we tested sera for brucellosis of 15 Hanwoo farms in the western part of Gyeong-buk province, resulting 5 farms were brucellosis positive in 2008. We collected blood from 277 heads in the brucellosis positive 5 farms, and performed serological diagnosis, brucella positive cattle which had shown higher than 200 antibody titer in tube agglutination test were slaughtered, supramammary lymph nodes were collected, and Brucella spp. wild type isolation and identification were performed. From these results, 15 of Brucella spp. wild type strains were isolated and all strains were identified as B. abortus biotype 1 by biological and molecular analysis. In the antimicrobial susceptibility test, all 15 strains had a similar susceptibility and resistance pattern. This study may be useful for bacteriological and epidemiological understanding of cattle brucellosis in Korea.

• Korean Journal of Veterinary Service
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• v.30 no.1
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• pp.95-102
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• 2007

The purpose of this study was to investigate the seroprevalence of infection with the production-limiting diseases in dairy cattle in Jeonbuk-Iksan area. The blood samples were collected from 260 dairy cows in 52 herds, and examined. The antibody rates against N caninum, M paratuberculosis, and bovine leukemia virus were 34.6%, 13.5% and 89.6%, respectively. All samples for bovine brucellosis were negative.

• Journal of Preventive Veterinary Medicine
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• v.42 no.4
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• pp.157-162
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• 2018

This study evaluated the protective effects of a combination of eight B. abortus recombinant proteins that were cloned and expressed into a pMal vector system and $DH5{\alpha}$: nucleoside diphosphate kinase (rNdk), 50S ribosomal protein (rL7/L12), malate dehydrogenase (rMDH), DNA starvation/stationary phase protection protein (rDps), elongation factor (rTsf), arginase (rRocF), superoxide dismutase (rSodC), and riboflavin synthase subunit beta (rRibH). The proteins were induced, purified, and administered intraperitoneally into BALB/c mice. The mice were immunized three times at weeks 0, 2, and 5 and then infected intraperitoneally (IP) with $5{\times}10^4CFU$ of virulent B. abortus 544 one week after the last immunization. The spleens were collected and the bacterial burden was evaluated at four weeks post-infection. The results showed that this combination produced a significant reduction of the bacterial burden in the spleen with a log reduction of 1.01 compared to the PBS group. Cytokine analysis revealed induction of the cell-mediated immune response in that TNF (tumor necrosis factor) and proinflammatory cytokines IL-6 (Interleukin 6) and MCP-1 (macrophage chemoattractant protein-1) were elevated significantly. In summary, vaccination with a combination of eight different proteins induced a significant protective effect indicative of a cell mediated immune response.