• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.517-523
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• 1989

This study was undertaken to establish reliable diagnostic-procedures for the microbiological monitoring of laboratory animals. Murine(mice and rats) antibodies against hemagglutinating virus of Japan(HVJ), mouse hepatitis virus(MHV) and Mycoplasma pulmonis(Mp) were detected sensitively and specifically in experimentally and naturally infected animals' sera by an indirect enzyme-linked immunosorbent assay(ELISA), using urease conjugated antimurine immunoglobulin. The sensitivity and specificity of the complement fixation test which has been apllied widely for serodiagnosis of HVJ, MHV and Mp infections were apparently lower than those of ELISA. From these results, the ELISA was found to be available for the serodiagnosis of HVJ, MHV and Mp infections in mice and rats.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2138-2140
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• 2016

The goal of this study was to identify a source of natural plant compounds with inhibitory activity against pepper mild mottle virus (PMMoV). We showed, using a half-leaf assay, that murrayafoline-A (1) and isomahanine (2) isolated from the aerial parts of Glycosmis stenocarpa have inhibitory activity against PMMoV through curative, inactivation, and protection effects. Using a leaf-disk assay, we confirmed that 2 inhibited virus replication in Nicotiana benthamiana. Using electron microscopy, we found that a mixture of the virus with 2 resulted in damage to the rod-shaped virus.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.187-191
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• 1998

Chemotherapy can not be applied for the control of fish viral diseases because viruses depend on host machinery for their replication. Although new control strategies including vaccination are under development, avoidance of virus introduction by rapid and correct diagnosis is the best way of fish viral disease control. Although observation of virus particles with an electron microscope is an easy method for virus detection, it take a few days for the sample preparation. In order to shorten the sample preparation time, microwave radiation was applied in the procedure. With this method, 15 seconds was enough for fixation of virus infected fish samples or cultured cells inoculated with infectious hematopoietic necrosis virus, which takes 2-4 hours with routine methods. Also four minutes was enough for polymerization of embedding resin which takes 24-48 hours with routine methods. Samples prepared with microwave were good enough for direct electron microscopic observation and immunogold labeling assay.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.527-533
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• 2017

We investigated the infection of nervous necrosis virus (NNV) in seven band grouper Hyporthodus septemfasciatus broodstocks, which have been reared in aquaculture farms in South Korea during 2012-2014. To investigate the prevalence of NNV within the broodstock, egg, sperm, and blood were sampled in the spawning season. The egg and sperm samples were subjected to a nested reverse transcription (RT) polymerase chain reaction (PCR) assay to detect NNV and were inoculated on SSN-1 cells to culture the virus. Blood samples were used to detect antibodies against NNV using enzyme linked immunosorbent assay (ELSIA). Positive values from ELISA were found in 39 of 162 samples (24%) in 2012, and 13 of 28 samples (46%) in 2014. Additionally, 4 of 34 broodstocks (11%) investigated in 2013-2014 were determined to be carriers from the nested RT-PCR and in vitro cultivation. The broodstocks in which antibodies against NNV were detected by ELISA, or in which NNV was detected by the nested RT-PCR assay, posed a risk of vertical transmission of NNV. Therefore, it is necessary to select virus-free broodstocks in seed production to reduce the possibility of the vertical transmission of NNV.

• KSBB Journal
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• v.16 no.6
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• pp.579-591
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• 2001

The cell growth inhibitor effect of cervical cancer cells was investigated by liposome mediated transfection (pRcCMVp53/lipofectin) and by transfection using adenovirus (AdCMVp57). The papilloma virus cancer cell lines we used in this study were HPV16 positive, having inhibiter gene, wild p53 gene, CaSki, SiHa, HPV18 positive HeLa, HeLaS3 and HPV negative C33A, HT3. LacZ gene of E.coli was used as the marker gene for the transfection efficiency. The effect on the inhibition of tumor cell growth was measured by cell count and cell viability though ELISA analysis and MTT assay. The inhibition of tumor cell growth was confirmed by measuring each assay for six days, comparing with the normal control cell growth. The cell growth of cervical cancer calls by transfection was significantly reduced and showed tittle differences among the cell lines. To eliminate the potential problem of Ad(adenovirus) contamination during rAAV production, rAAV can be produced by a triple transfection of vector plasmic, packaging plasmid, and adenovirus helper plasmid. To examine the helper functions of Ad plasmids on the production of rAAV vector, we carried out cotransfection of three plasmids, AAV vector, packaging construct, and Ad helper plasmids. The optimized transfection condition for calcium phosphate method is 25ug of total DNA per 10-cm-diameter plate of 293 cell. We found that rAAV yields peaked at 48hr after Ad infection. The titer of rAAV was measured by the dot blot analysis to measure the number of particles/ml based on the quantification of viral DNA. Recent1y, Kombucha(fungi) was identified as a very potent antileukefic agent. In the present study, effect of natural toxin(plankton) and Kombucha is PSP(GTXI-3, neoSTX), on various MTT assay cervical cancer cell line. Toxin(GTX 1-3, neoSTX) also inhibited the proliferation in primary cervical cancer calls in a dose-dependent toxin concentration. These results showed that toxin was very potent in inhibiting the proliferation of cervical cancer calls in vitro. Toxins and Kombuoha exhibited a dose dependent inhibition of cellular proliferation in cancer cell line.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.80-80
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• 1993

(목적) 본 연구에서 사용된 바이러스는 HIV-1 nef유전자가 일부 삭제되고 대신 Chloramphenicol acetyltransferase(CAT)가 pSVCAT recombinant 바이러스다. 이러한 recombinant 바이러스를 사용하는 이유는 첫째, CAT activity가 매우 민감하므로 바이러스의 복제억제 정도를 정확하게 측정 할 수 있고 둘째, simian immunodeficiency virus(SIV)의 경우 nef 유전가 in vivo에서는 바이러스의 복제에 필수적이므로 HIV가 SIV와 유사한 것으로 미루어 본 연구에서 사용되는 recombinant SVCAT 바이러스가 안전한 것으로 고려되기 때문이다. (방법) 특히 화합물이 HIV-1의 복제에 얼마나 영향이 있는가는 1) 어느정 도의 virus inoculm을 넣었는지 2) 사용하는 cell line 3) 사용한 cell line의 infection kinetics 4) 실험의 지속기간 5) 테스트하는 assay의 sensitivity에 의존한다. 따라서 $10^{5}$ cell의 H9과 sup T1을 24 well plate에 넣고 sup T1 cell line의 경우 3일 후 항 화합물에 의한 syncytia 형성 및 CAT activity의 억제정도를 현재 AIDS drug으로 쓰이고 있는 Zidovudine을 control로 비교 관찰하였다. H9 cell line의 경우 3일 간격으로 media의 3/4을 fresh media로 바꾸어 주고 9일 후 CAT assay를 하였다. 이러한 assay에서 activity를 보이는 화합물을 reverse transcriptase와 P24 ELISA assay를 재확인하였다.다.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.339-347
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• 2012

Viral safety is an important prerequisite for clinical preparations of mammalian cell culture-derived biopharmaceuticals, because numerous adventitious viruses have been contaminated during the manufacturing process. In particular, Chinese hamster ovary (CHO) cells are highly susceptible to several RNA viruses including reovirus (Reo), bovine viral diarrhea virus (BVDV), and bovine parainfluenza virus (BPIV) and there have been reports of such viral contaminations. Therefore, viral detection during the CHO cell process is necessary to ensure the safety of biopharmaceuticals against viruses. In this study, a multiplex reverse transcription (RT)-PCR assay was developed and subsequently evaluated for its effectiveness as a means to simultaneously detect Reo, BVDV, and BPIV during the manufacture of cell culture-derived biopharmaceuticals. Specific primers for Reo, BVDV, and BPIV were selected, and a multiplex RT-PCR was optimized. The sensitivity of the assay for simultaneous amplification of all viral target RNAs was $7.76{\times}10^2\;TCID_{50}/ml$ for Reo, $7.44{\times}10^1\;TCID_{50}/ml$ for BVDV, and $6.75{\times}10^1\;TCID_{50}/ml$ for BPIV. The multiplex RT-PCR was proven to be very specific to Reo, BVDV, and BPIV and was subsequently applied to the validation of CHO cells artificially infected with each virus. It could detect each viral RNA from CHO cells as well as culture supernatants. Therefore, it was concluded that the multiplex RT-PCR assay can be applied to detection of the adventitious viruses during the manufacture of cell culture-derived biopharmaceuticals.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.71.1-71.10
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• 2020

Background: Feline calicivirus (FCV) is a major and highly infectious pathogen in cats worldwide. However, there have been limited studies about the status of FCV infections in Korea. Objectives: To investigate the current status of FCV infections in stray cats in Korea. Methods: A novel reverse transcription polymerase chain reaction (RT-PCR) assay was developed based on the conserved nucleotide sequences of reported FCV strains. Field swab samples were collected from 122 cats (2 hospital admitted cats and 120 stray cats) in 2016 and 2017. All the samples were tested by virus isolation and 2 different RT-PCRs, including the novel RT-PCR, for the detection of FCV. Results: The novel RT-PCR assay showed no cross-reactivity to the nucleic acids of the other feline pathogens tested, and the limit of detection was calculated as 10⁰ TCID₅₀/mL based on an in vitro assessment. The novel RT-PCR assay detected 5 positive samples from the 122 field samples, which showed perfect agreement with the results of the virus isolation method. In contrast, another RT-PCR assay used in a previous study in Korea detected no positive samples. The prevalence of FCV infection in stray cats was 2.5% (3/120) based on the results of virus isolation and the novel RT-PCR assays. Conclusions: The current study is the first report of the detection and prevalence of FCV in stray cats in Korea. The novel RT-PCR assay developed in this study showed high sensitivity and specificity, which indicates a useful diagnostic assay to identify FCV infection in cats.

• Korean Journal of Veterinary Service
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• v.45 no.1
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• pp.19-30
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• 2022

In this study, a simple loop-mediated isothermal amplification (LAMP) combined with visual detection method (vLAMP) assay was developed for the rapid and specific detection of African swine fever virus (ASFV), overcoming the shortcomings of previously described LAMP assays that require additional detection steps or pose a cross-contamination risk. The assay results can be directly detected by the naked eye using hydroxynaphthol blue after incubation for 40 min at 62℃. The assay specifically amplified ASFV DNA and no other viral nucleic acids. The limit of detection of the assay was <50 DNA copies/reaction, which was ten times more sensitive than conventional polymerase chain reaction (cPCR) and comparable to real-time PCR (qPCR). For clinical evaluation, the ASFV detection rate of vLAMP was higher than cPCR and comparable to OIE-recommended qPCR, showing 100% concordance, with a κ value (95% confidence interval) of 1 (1.00~1.00). Considering the advantages of high sensitivity and specificity, no possibility for cross-contamination, and being able to be used as low-cost equipment, the developed vLAMP assay will be a valuable tool for detecting ASFV from clinical samples, even in resource-limited laboratories.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.57-61
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• 1992

To determin the accuracy of serological methods in detecting Borna-disease(BD) viral antibodies, 273 experimentally infected rabbit sera were compared by using indirect immunofluorescence antibody test(IFA), serum neutralization test(SN) and enzyme-linked immunosorbent assay(ELISA). One hundred twenty-three serum samples had BD viral antibodies detected by IFA. CELISA antibodies to BD virus were also present in the same one hundred twenty-three serum samples. However, neutralization test antibodies to BD virus were present in 27 of the in rabbit serum samples. Neutralization test was sensitive in comparison with KFA and CELISA. In comparison with IFA, CELISA was both sensitive and specific in detecting BD viral antibodies. These results extend observations made with laboratory animals to the diagnosis of naturally infected animals.