• 대한바이러스학회지
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• 제26권2호
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• pp.191-204
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• 1996

The characterization of the 5 Korean isolates (K96P10, K94P05, K91P55, K87P39, and K82P01) of Japanese encephalitis virus (JEV) was compared with JE virus prototype Nakayama-NIH (NKY-NIH) using prM/M and envelope gene sequences of the JEV genome and phylogenetic analysis. The antigenic analysis of these viruses were done by the cross-hamagglutination inhibition (HI) test using polyclonal antibodies against Korean isolates and NKY-NIH. The sequence homology of the Korean isolates and NKY-NIH ranged between 87.4 % - 95.6 % at the nucleotide level and between 98.2 % - 97.2 % at the amino acid level over the E nucleotides compared. Alignment of E protein amino acid sequences revealed that residue positions E89, E129, E221, E244, E327, E366, E459, and E477 characterized the Korean strains. According to phylogenetic analysis bases on the E nucleotide, there are at least 2 genetic types of JEV existing in Korea and Korean strains were distinct from NKY-NIH. However, the cross HI test results of all the Korean isolates were serologically no different from NKY-NIH strain.

• 한국임상수의학회지
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• 제30권4호
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• pp.236-240
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• 2013

A total of 170 litters (575 samples) of aborted and stillbirth fetuses submitted to the Gyeongsangbuk-Do Veterinary Service Laboratory (GVSL) between January 2006 and December 2010 from pig farms in Gyeongbuk province were studied to identify porcine abortion- and stillbirth-associated viruses such as Porcine parvovirus (PPV), Encephalomyocarditis Virus (EMCV), Japanese Encephalitis Virus (JEV), Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), and Aujeszky's Disease Virus (ADV). Virus was not detected by PCR in 36 litters, but viral antibody was detected by HI and ELISA in 93 litters. The majority of etiological viruses were PPV (67 litters, 39.4%), EMCV (50 litters, 29.4%), PRRSV (15 litters, 8.8%), and JEV (11 litters, 6.5%); ADV was not detected by either PCR or ELISA. Single infection occurred in 52 litters (30.6%), co-infection occurred in 41 litters (24.1%), and unknown cases with no detection of any of the five viruses occurred in 77 litters (45.3%).

• 미생물학회지
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• 제46권2호
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• pp.140-147
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• 2010

일본뇌염바이러스(Japanese encephalitis virus)는 모기 매개성 플라비바이러스에 속하며, 주로 동남아시아 지역에서 유행성 바이러스성 뇌염을 일으킨다. 일본뇌염바이러스는 외피를 가진 작은 바이러스로서, 양성가닥 RNA 게놈을 가지고 있다. 감염성을 띤 바이러스 입자는 capsid (C), membrane (M; prM 전구체로부터 생성), 및 envelope (E)과 같은 3개의 구조단백질로 이루어져 있다. 본 연구에서는 일본뇌염바이러스 생산과 정에 M 단백질의 N-말단부위에 위치한 극성 아미노산 잔기의 역할을 분석하였다. 일본뇌염바이러스의 infectious cDNA를 활용하여, M 단백질의 $E^9$와 $K^{15}K^{16}E^{17}$ 잔기를 알라닌으로 치환시킨 2개의 mutant cDNA (Mm1과 Mm2)를 각각 제작하였다. 각각의 cDNA로부터 합성된 mutant RNA를 세포에 트랜스펙션시킴으로써, 비록 세포 내에 축적된 3개의 구조단백질양은 변화가 없으나, 이들 세포로부터 생산된 바이러스의 양은 Mm2 RNA의 경우 ~1,000배 감소됨을 관찰하였다. 흥미롭게도, Mm2 RNA로부터 발현된 mutant M 단백질은 wild-type M 단백질을 인지하는 항혈청에는 반응하지 않았으나, mutant M 단백질을 항원으로 제작된 항혈청에는 반응하는 것을 알 수 있었다. 본 실험결과는 일본뇌염바이러스 M 단백질을 구성하는 3개의 극성 아미노산 잔기($K^{15}K^{16}E^{17}$)가 바이러스의 생산과정에 관여한다는 것을 암시한다. 앞으로, wild-type 또는 mutant M 단백질(Mm2)을 인식하는 2개의 항혈청은 이 단백질의 기능연구에 유용한 재료로 사용될 것으로 기대된다.

• 한국동물위생학회지
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• 제24권4호
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• pp.359-367
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• 2001

A serological survey was performed to establish basic data for the prevalence of antibodies to some major diseases of domesticated boar serum samples from January to December 2000. Sera collected in breeding farms in Gyeongbuk province were tested for Aujeszky's disease virus(ADV), Porcine reproductive and respiratory syndrome virus(PRRSV), Porcine parvovirus(PPV), Japanese encephalitis virus (JEV), Bordetella bronchiseptica(B bronchiseptica), Mycoplasma ; APP), Toxoplasma, and Brucella. There was no antibody to ADV in domesticated boars serum samples detected by Anti-ADV-gpI assay kit. Sero-positive samples to PRRS by IFA were 0.9%(3/330) The HI titers to PPV ranged variously from less than 10 to over 1,280. Two hundred ninety-four out of 330 tested sera showed HI titer of less than 10. In HI test to JEV, 90.3% of the sera (298/330) were below 10. The majority of the serum samples had low prevalence of the antibody B bronchiseptica. ELISA titers to M hyopneumoniae ranged variously from $\leq$ 10 to $\geq$ 1,280. Antibody titers to A pleuropneumoniae type 2(APP2) and type 5(APP5) were 58.2% and 52.7%, respectively, and the tested samples showing ELISA antibody titers of less than 20. There was no significant geographical difference between APP2 and APP5 in this study. In the antibody test of Toxoplasma, 11.5%(38/330) were positive and samples were all negative in sera test of Brucella.

• 한국동물위생학회지
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• 제34권2호
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• pp.117-123
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• 2011

This experiment was conducted to investigate the presence of recognized abortifacient viruses from aborted fetuses and stillborn piglets in cases of reproductive failure in sows by PCR. A total of 219 samples of aborted fetuses or stillborn piglets, submitted to the School of Veterinary Medicine of Kangwon National University between 2006 and 2009 May, were collected from 5 provinces in Korea. Abortifacient virus infections were detected in 82 (37.4%) out of 219 aborted fetuses or stillborn piglets as well as on 39 (40.2%) out of 97 pig farms. The major viral infections were porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV) and Aujesky's disease virus (ADV) for which 46 (21%), 19 (8.6%) and 16 (7.3%) were positive, respectively, with 9 fetuses had complicated infection of PCV2+PRRSV or ADV or both. And 8 (3.6%) for SIV, 3 (1.3%) for PPV and 1 (0.4%) for JEV were positive as minor viral infection. The results suggest that PCV2, PRRSV, ADV is apparently the most important viral infectious agents associated with fetal infection leading to abortion or stillbirth in Korea. SIV, PPV and JEV might have a minor impact on reproductive disease.

• KSBB Journal
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• 제13권3호
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• pp.231-237
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• 1998

세계보건기구 (WHO)가 백신 생산에 권장하고 있는 표준세포 주인 Vero 세포에 약독화 일본뇌염바이러스인 SA14-14-2 ( (PDK)를 연속 계대배양을 통해 적응(adaptation)시켜, tIter가 $10^7$pfu/mL을 넘는 SA-14-14-2(Vero)을 분리하였다 바이러스 배양 최적온도는 $35^{\circ}C$이며, T -flask에서 배양된 바이러스의 최고 tIter는 감염 후 4일째에 $4\times10^7$ pfu/mL로 관찰되었다. 또한 무혈청배지에서도 바이러스 증식이 활발하여 2% 혈청이 보충된 정우와 거의 비슷한 바이라스 tIter를 보였다. 바이러스 대량 배양을 위해 roller bottle culture와 미 립 담체 플 이용한 spinner flask culture 가능성에 대하여 고찰하였다 바이러스 감염을 위한 미립담체에서의 Vera cell monolayer는 초기 세포 농도 $4\times10$ cells/mL로 접종하여 50 rpm에서 7일간 배양하여 얻을 수 있었다. 바이러스의 roller bottle 배양이 spinner flask 배양보다 바이러스 tIter변에서 2배 내지 3배 높 았고, $10^7$pfu/mL을 넘는 배양 기간도 하루 죄었다. 하지만 두 배양 방법 모두 T -flask 배양에서와 같이 무혈청 배지를 사용 하여도 바이라스 증식이 활발했고, 최고조의 tIter를 보이는 배 양기간은 감염 후 2일째로써 T -flask 배양에서 보다 2일 빨랐다. Roller bottle culture의 경우, 감염 후 3일부터 17일까지 2 일 간격으로 배양액을 무혈청 EMEM으로 100% 교체하면서 매 양을 지속한 결과 3일부터 9일까지 $10^7$pfu/mL을 념는 tIter가 유지되는 것이 확인되어 바이러스의 multi-harvest가 가능한 것 로 고찰되었다. 상기의 결과는 생산성 면에서 매우 유리한 결 과로 제품의 생산 단가플 낮추고 작업 노력을 절감하는 기대 효 과가 클 것으로 예측된다.

• 대한바이러스학회지
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• 제27권2호
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• pp.209-216
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• 1997

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NlH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.

• 한국동물위생학회지
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• 제34권2호
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• pp.111-116
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• 2011

Artificial insemination (AI) of swine is a very useful reproductive tool and that offers convenience in the Korean swine industry. Since many viruses have been reported to be excreted through boar semen, we investigated the presence of antibodies and antigens against viruses causing reproductive failure in semen of boar in 349 semen samples collected from six Korean AI centers. Viral antigens were detected by polymerase chain reaction (PCR) or reverse transcription-PCR predominantly. The results was as follows. The major reproductive failure causing factor was porcine circovirus type 2 (PCV2), followed by porcine reproductive and respiratory syndrome virus (PRRSV) ($X^2$=166.64, P<0.001). PCV2 and PRRSV, Japanese encephalitis virus (JEV), encephalomyocarditis virus (EMCV) was detected in 73 samples (20.9%), 44 samples (12.6%), 4 samples (1.1%), 3 samples (0.9%), respectively and porcine parvovirus in one sample (0.3%) Classical swine fever virus (CSFV), bovine viral diarrhea virus and Aujeszky's disease virus (ADV) were not detected. Enzyme-linked immunosorbent assay was carried out in 111 serum samples from three AI centers. In most pigs, antibodies response was showed prominently in CSFV (105 sera, 94.6%) ($X^2$=82.580, P<0.001), followed by, in PRRSV (100 sera, 90.1%), PCV2 (92 sera, 90.1%), and PPV (8 sera, 82.9%). ADV antibody was not detected. Thus, the experimental results will be used for the base data, with respect to the state of viral stillbirth in general pig farms, as well as AI centers and breeding farms in Korea.

• 대한수의학회지
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• 제29권2호
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• pp.109-114
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• 1989

1982년(年)부터 1984년도(年度)까지 3년간(年間)에 걸처, 일본내(日本內) 중부(中部) Saitama현(縣)의 우(牛) 1,306두(頭)와 남부(南部)의 Kagoshima현(縣)의 우(牛) 536두(頭)를 대상(對象)으로 하여 일본뇌염(日本腦炎)바이라스 (JEV)의 적혈구응집억제(赤血球凝集抑制) (HI) 항체양성율(抗體陽性率)을 검사(檢査)한 바, Kagoshima현(縣)에선 68.8% 그리고 Saitama 현(縣)에서는 65.5%가 양성(陽性)이었다. 계절별(季節別)로는 양지역(兩地域)이 공(供)히 하절(夏節)에 항체양성율(抗體陽性率)이 높았고, 연령별(年齡別) 양성율(陽性率)은 Saitama 현(縣)의 경우 64.0%부터 82.8%까지 분포(分布)하고, Kagoshima현(縣)의 우(牛)는 1세군(歲群)에서 29.4%, 2세군(歲群)에선 50.0%, 3세군(歲群)에선 47.4% 그리고 4세군(歲群)에선 74.5%의 양성율(陽性率)을 나타내었다. 그리고 양지역(兩地域)의 연령(年齡)과 항체력가간(抗體力價間)에는 상관성(相關性)이 없었고, Saitama현(縣) 우(牛)의 역가(力價)는 연령(年齡)에 따라 15.3~22.5, Kagoshima 현우(縣牛)은 20.0~32.3이었다.

• Journal of Microbiology and Biotechnology
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• 제28권11호
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• pp.1928-1936
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• 2018

Recently, human infections caused by severe fever with thrombocytopenia syndrome virus (SFTSV), which can lead to fatality, have dramatically increased in East Asia. With the unavailability of vaccines or antiviral drugs to prevent and/or treat SFTSV infection, early rapid diagnosis is critical for prevention and control of the disease. Here, we report the development of a simple, rapid and sensitive portable detection method for SFTSV infection applying reverse transcription-loop mediated isothermal amplification (RT-LAMP) combined with one-pot colorimetric visualization and electro-free reaction platform. This method utilizes a pocket warmer to facilitate diagnosis in a resource-limited setting. Specific primers were designed to target the highly-conserved region of L gene of SFTSV. The detection limit of the RT-LAMP assay was approximately $10^0$ viral genome copies from three different SFTSV strains. This assay exhibited comparable sensitivity to qRT-PCR and 10-fold more sensitivity than conventional RT-PCR, with a rapid detection time of 30 to 60 minutes. The RT-LAMP assay using SFTSV clinical specimens has demonstrated a similar detection rate to qRT-PCR and a higher detection rate compared to conventional RT-PCR. Moreover, there was no observed cross-reactive amplification of other human infectious viruses including Japanese Encephalitis Virus (JEV), Dengue, Enterovirus, Zika, Influenza and Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This highly sensitive, electro- and equipment-free rapid colorimetric visualization method is feasible for resource-limited SFTSV field diagnosis.