• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2135-2145
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• 2015

VP7, an outer capsid protein of grass carp reovirus (GCRV), was expressed and displayed on the surface of Saccharomyces cerevisiae for developing an efficient vaccine against hemorrhagic disease of grass carp. The result of flow cytometry analysis indicated that protein VP7 could be displayed on the surface of yeast cells after inducing with galactose. The expression of VP7 was confirmed by western blot analysis and further visualized with confocal microscopy. The specific antibodies against VP7 generated from mice were detectable from all immune groups except the control group, which was immunized with untransformed yeast cells. The displaying VP7 on glycosylation-deficient strain EBYΔMnn9 was detected to induce a relatively low level of specific antibody amongst the three strains. However, the antiserum of EBYΔM9-VP7 showed relative high capacity to neutralize GCRV. Further neutralization testing assays indicated that the neutralizing ability of antiserum of the EBYΔM9-VP7 group appeared concentration dependent, and could be up to 66.7% when the antiserum was diluted to 1:50. This result indicates that appropriate gene modification of glycosylation in a yeast strain has essential effect on the immunogenicity of a yeast-based vaccine.

• Journal of Ginseng Research
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• 제43권2호
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• pp.218-225
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• 2019

Background: Streptococcus pneumoniae, more than 90 serotypes of which exist, is recognized as an etiologic agent of pneumonia, meningitis, and sepsis associated with significant morbidity and mortality worldwide. Immunization with a pneumococcal pep27 mutant (${{\Delta}}pep27$) has been shown to confer comprehensive, long-term protection against even nontypeable strains. However, ${{\Delta}}pep27$ is effective as a vaccine only after at least three rounds of immunization. Therefore, treatments capable of enhancing the efficiency of ${{\Delta}}pep27$ immunization should be identified without delay. Panax ginseng Mayer has already been shown to have pharmacological and antioxidant effects. Here, the ability of Korean Red Ginseng (KRG) to enhance the efficacy of ${{\Delta}}pep27$ immunization was investigated. Methods: Mice were treated with KRG and immunized with ${{\Delta}}pep27$ before infection with the pathogenic S. pneumoniae strain D39. Total reactive oxygen species production was measured using lung homogenates, and inducible nitric oxide (NO) synthase and antiapoptotic protein expression was determined by immunoblotting. The phagocytic activity of peritoneal macrophages was also tested after KRG treatment. Results: Compared with the other treatments, KRG significantly increased survival rate after lethal challenge and resulted in faster bacterial clearance via increased phagocytosis. Moreover, KRG enhanced ${{\Delta}}pep27$ vaccine efficacy by inhibiting reactive oxygen species production, reducing extracellular signal-regulated kinase apoptosis signaling and inflammation. Conclusion: Taken together, our results suggest that KRG reduces the time required for immunization with the ${{\Delta}}pep27$ vaccine by enhancing its efficacy.

• 생명과학회지
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• 제32권5호
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• pp.375-390
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• 2022

인수공통 호흡기바이러스인 인플루엔자바이러스 감염으로 인해 공중보건과 가축산업에 심각한 피해가 지속적으로 발생하고 있다. 인플루엔자 백신 접종을 통해 항원형이 일치하는 바이러스 감염에 대해 우수한 방어면역을 제공하고 있으나, 효과적인 바이러스 감염 제어에는 여전히 큰 공백이 존재하고 있다. 다양한 항원형을 갖는 바이러스에 동시방어가 가능한 범용인플루엔자백신 개발과 함께 바이러스 치료효과를 제공하는 항바이러스제의 개발도 중요한 접근법으로 고려되고 있다. 현재 널리 사용되고 있는 인플루엔자 항바이러스제의 불완전한 치료효과와 내성바이러스의 출현 등의 문제들로 인해 식물 유래 천연물의 항바이러스 활성에 대한 관심이 증가하고 있다. 특히, 현재 진행 중인 코로나-19 팬데믹은 범용적인 항바이러스 활성을 갖는 안전하고 효과적인 항바이러스제 개발의 필요성을 뚜렷이 보여준다. 본 리뷰는 현재까지 보고된 천연물의 항인플루엔자바이러스 활성을 요약하였다. 또한, 항바이러스 활성을 갖는 천연물의 바이러스 사멸활성과 면역증강활성을 이용하는 신규 백신개발과 면역증강제 개발 가능성에 대해서도 분석하였다.

• 대한수의학회지
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• 제45권2호
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• pp.199-205
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• 2005

DNA fingerprint patterns of 8 Brucella reference strains and 15 B. abortus field isolates were characterized by repetitive element sequence-based PCR (rep-PCR) using BOX- and ERIC-primers in this study. AMOS PCR differentiated all Brucella field isolates from B. abortus RB51, a vaccine strain by producing a B. abortus-specific 498 bp band. Rep-PCR using BOX-primer produced 13 to 18 bands with sizes of between 230 and 3,300 bp, and discriminated Brucella strains to the species level except B. canis and B. suis. PCR products amplified with ERIC primers were, however, not appropriate for differentiating the Brucella isolates. DNA fingerprint patterns for all B. abortus field isolates were identical among them and were put on one cluster with B. abortus biovar 1 reference strain in the dendrogram, indicating they were highly clonal. These results suggested that rep-PCR using BOX primer might to be a useful tool for calculating genetic relatedness among the Brucella species and for the study of brucellosis epidemiology.

• 대한수의학회지
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• 제56권1호
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• pp.37-40
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• 2016

A total of 131 Pasteurella (P.) multocida strains were isolated from the lungs of 1,064 pigs with respiratory clinical signs nationwide during 2009-2010 and 2013-2014. The strains of P. multocida comprised 77.1% serotype A and 22.9% serotype D. Analysis of a recent P. multocida outbreak in Korean pigs showed that the isolation rate of serotype D decreased annually. The incidence of antimicrobial resistance, as measured using minimal inhibitory concentration values, has decreased recently. Overall, further studies to characterize P. multocida isolated from pigs in Korea are needed to prevent P. multocida infection in the Korean swine industry

• Journal of Microbiology and Biotechnology
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• 제32권11호
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• pp.1396-1405
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• 2022

Cholera remains a major global public health problem, for which oral cholera vaccines (OCVs) being a valuable strategy. Patients, who have recovered from cholera, develop antibody responses against LPS, cholera toxin (CT), toxin-coregulated pilus (TCP) major subunit A (TcpA) and other antigens; thus, these responses are potentially important contributors to immunity against Vibrio cholerae infection. However, assessments of the efficacy of current OCVs, especially inactivated OCVs, have focused primarily on O-antigen-specific antibody responses, suggesting that more sophisticated strategies are required for inactivated OCVs to induce immune responses against TCP, CT, and other antigens. Previously, we have shown that the toxT-139F allele enables V. cholerae strains to produce CT and TCP under simple laboratory culture conditions. Thus, we hypothesized that V. cholerae strains that express TCP via the toxT-139F allele induce TCP-specific antibody responses. As anticipated, V. cholerae strains that expressed TCP through the toxT-139F allele elicited antibody responses against TCP when the inactivated bacteria were delivered via a mouse model. We have further developed TCP-expressing V. cholerae strains that have been used in inactivated OCVs and shown that they effect an antibody response against TcpA in vivo, suggesting that V. cholerae strains with the toxT-139F allele are excellent candidates for cholera vaccines.

• 대한수의학회지
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• 제41권1호
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• pp.59-65
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• 2001

To clarify for the presence of infectious bronchitis virus (IBV) in Korea before 1986, in which the virus was first isolated, materials collected from chicken diagnostic consignments between 1980 and 1985 and propagated in chicken embryos or cell cultures were screened by the reverse transcriptase polymerase chain reaction (RT-PCR) targeted to the nucleocapsid gene of the virus. Among 11 samples examined, one sample (IBV-SNU80108) submitted in 1980 showed specific PCR product (281 bp). When the amplified product was sequenced, together with IBV vaccine virus H120 strain, and compared with the data for ten other IBV strains derived from the GeneBank, identities between IBV-SNU80108 and other strains in nucleotide and amino acid sequences ranged 96.3% to 63.7% and 96.4% to 69%, respectively. IBV-SNU80108 was distinct from H120 strain by showing 91.9% and 92.9% identities in the respective sequences. This data suggested that IBV genetically distinctive from other foreign IBV strains might be present before 1986 in Korea.

• 대한수의학회지
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• 제60권3호
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• pp.109-116
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• 2020

This study aimed to develop a semi-nested polymerase chain reaction assay for the direct detection of Mycoplasma synoviae (M. synoviae) from clinical samples using three newly designed oligonucleotide primers specific to the variable lipoprotein haemagglutinin (vlhA) gene and differentiate M. synoviae field strains based on a nucleotide deletion or the insertion of the proline-rich repeat (PRR) region of the vlhA gene. The developed semi-nested polymerase chain reaction (PCR) assay revealed positive results in 12 out of 100 clinical samples collected from chickens showing lameness and joint swelling. Six positive samples were selected randomly for sequencing, and sequence analysis revealed 96.3-100% nucleotide identities compared to the reference sequences. Phylogenetic analysis showed that sequences of the strains in this study were closely related to WVU1853 (Spain), CK.MS.UDL.PK.2014.2 (Pakistan), and F10-2AS (USA) strains, but they were distinct from the M. synoviae-H vaccine strain sequence. M. synoviae obtained from these samples were identified as types A and C with a length of 38 and 32 amino acids, respectively. These results indicated that the specific and sensitive semi-nested PCR could be a useful diagnostic tool for the direct identification of clinical samples, and the sequence analysis of the partial vlhA gene can be useful for typing M. Synoviae.

• Fisheries and Aquatic Sciences
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• 제22권7호
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• pp.14.1-14.8
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• 2019

Olive flounder (Paralichthys olivaceus) is the major species developed for aquaculture in South Korea. Over the long history of olive flounder aquaculture, complex and diverse diseases have been a major problem, negatively impacting industrial production. Vibriosis is a prolific disease which continuously damages olive flounder aquaculture. A bacterial disease survey was performed from January to June 2017 on 20 olive flounder farms on Jeju Island. A total of 1710 fish were sampled, and bacteria from the external and internal organs of 560 fish were collected. Bacterial strains were identified using 16 s rRNA sequencing. Twenty-seven species and 184 strains of Vibrio were isolated during this survey, and phylogenetic analysis was performed. Bacterial isolates were investigated for the distribution of pathogenic and non-pathogenic species, as well as bacterial presence in tested organs was characterized. V. gigantis and V. scophthalmi were the dominant non-pathogenic and pathogenic strains isolated during this survey, respectively. This study provides data on specific Vibrio spp. isolated from cultured olive flounder in an effort to provide direction for future research and inform aquaculture management practices.