• Journal of Life Science
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• v.3 no.4
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• pp.209-215
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• 1993

어류의 대량폐사의 원인은 여러 가지가 있을 수 있는데 가장 중요한 것 중의 하나가 바이러스 감염에 의한 것이다. 우리나라 송어양식의 경우, 바이러스성 질병에 의한 대량폐사가 발생하여 매년 수천만마리의 치어가 폐사되어 왔는데 이 질병의 원인을 조사한 결과, 전염성 췌장 괴사 바이러스(Infectious Pencreatic Necrosis Virus ; IPNV)와 전염성 조혈기 괴사 바이러스(Infectious Hematopoietic Necrosis Virus ; IHNV)가 분리되어 이들의 대량폐사의 병원체임읠 밝혀내었다. 따라서 본 총설에서는 연어과 어류중 양식 대상종인 무지개송어 양식시 전염성과 병원성이 강해 치어기에 들어 대량폐사를 유발시키는 IHNV에 대해 최근 연구 결과를 중심으로 바이러스 분리 및 동정, 신속진단, 바이러스 백신 기초 기술 개발순으로 기술하고자 한다.

• Korean Journal of Microbiology
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• v.34 no.1_2
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• pp.69-73
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• 1998

We have cloned and analyzed cDNA coding for nucleocapsid protein N from infectious hematopoietic necrosis virus(IHNV), IHNV-PRT, which was isolated in Korea. The N gene had open reading frame of 1,176 bp that encoded a 391 amino acids with a molecular weight of 42.3 kDa. The deduced amino acid sequence of N protein was 75-90% identical to those of foreign isolates, IHNV, but was 43% and 38% identical to those of other species of fish rhabdovirus, hirame rhabdovirus(HRV) and viral hemorrahagic septicemia virus(VHSV), respectively. However, it revealed high levels of sequence identity between 214-265 amino acid sequences among all species of fish rhabdovirus.

• Journal of fish pathology
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• v.31 no.2
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• pp.81-85
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• 2018

Fetal bovine serum (FBS) is an essential element of cell growth and can also affect the viral replication. In this study, we tried to find out whether FBS concentration affects the viral infectivity titer of IHNV and IPNV. EPC cells were suspended with MEM supplemented with various concentrations of FBS (MEM0, MEM2, MEM5 and MEM10) and cultured in 96-well plate. Each virus was 10-fold diluted virus and inoculated in 96-well plate. The highest infectivity titer of IHNV was $10^{7.88}\;TCID_{50}/mL$ in 96-well plate using MEM5 and the lowest one was $10^{7.30}\;TCID_{50}/mL$ in 96-well plate using MEM10. The highest infectivity titer of IPNV was $10^{7.47}\;TCID_{50}/mL$ in 96-well plate using MEM5 and the lowest one was $10^{6.97}\;TCID_{50}/mL$ in 96-well plate using MEM10. This study showed that not only 0% FBS but 10% FBS leads low infectivity titer of IHNV and IPNV. Therefore, it is considered that the desirable concentration of FBS is 2% or 5% for measurement of infectivity titer of IHNV and IPNV.

• Journal of fish pathology
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• v.35 no.2
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• pp.157-165
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• 2022

Single-cycle viruses generated by reverse genetic technology are replication-incompetent viruses due to the elimination of gene(s) essential for viral replication, which provides a way to overcome the safety problem in attenuated viruses. Infectious hematopoietic necrosis virus (IHNV) is a major pathogen causing severe damage in cultured salmonid species. In the present study, we generated a single-cycle IHNV lacking the transmembrane and cytoplasmic domain in the G gene (rIHNV-GΔTM) and evaluated the prophylactic potential of rIHNV-GΔTM in rainbow trout (Oncorhynchus mykiss). To produce rIHNV-GΔTM, IHNV G protein-expressing Epithelioma papulosum cyprini (EPC) cells were established. However, as the efficiency of rIHNV-GΔTM production in EPC cell clones was not high, fish were immunized with a low-tittered single-cycle virus (1.5 × 10² PFU/fish). Despite the low dose, the single-cycle IHNV induced significant protection in rainbow trout against IHNV infection, suggesting high immunogenicity of rIHNV-GΔTM. No significant difference in serum ELISA titers against IHNV between the rIHNV-GΔTM immunized group and the control group suggests that the immunized dose of rIHNV-GΔTM might be too low to induce significant humoral adaptive immune responses in rainbow trout. The involvement of adaptive cellular immunity or innate immunity in the present significantly higher protection by the immunization with rIHNV-GΔTM should be further investigated to know the protection mechanism.

• Journal of fish pathology
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• v.16 no.3
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• pp.161-164
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• 2003

An Infectious hematopoietic necrosis virus strain (IHNV-RTK) was isolated from cultured rainbow trout at Kumi and Jechun area in Korea during 2000 and 2001. In the RT-PCR amplification with the specific primer set designed from IHNV G protein region, a 540 bp PCR product was amplified from the RTK strain. The RTK strain showed higher sequence homology with the published IHNV G protein genes (RB-76, LR-73, Col-85, and Carson-89)

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.6
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• pp.948-955
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• 1997

Immunomagnetic separation of virus coupled with .reverse transcription-polymerase chain reaction (IMS-PCR) was performed with infectious hematopoietic necrosis virus (IHNV). A DNA fragment of expected size was synthesized in the RT-PCR with total RNA extracted from IHNV inoculated CHSE-214. In a SDS-PAGE analysis, a protein band of over 70kDa was detected from non-infected cells and cells inoculated with IHNV and infectious pancreatic necrosis virus (IPNV). This protein was detected in the Western blot analysis probably because of non-specific reaction to monoclonal antibody against IHNV nucleocapsid protein. In the immunomagnetic separation, magnetic beads coated with monoclonal antibody against the IHNV nucleocapsid protein was incubated with supernatant from IHNV inoculated CHSE-214 cells. During this process, the non-specifically reacting protein could be removed by washing the magnetic bead with PBS in the presence of an external magnetic field, and viral proteins were detected from the remaining, cleaned magnetic beads. It was necessary to extract viral RNA from the captured virus particles before RT-PCR, and no DNA product was detected when the captured virus was only heated 5 min at $95^{\circ}C$. A PCR-product of expected size was synthesized from IMS-PCR with magnetic beads double coated either by goat anti-mouse IgG antibody -monoclonal antibody or streptavidin - biotin conjugated monoclonal antibody.

• Journal of fish pathology
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• v.31 no.1
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• pp.1-8
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• 2018

Causative agent of infectious hematopoietic necrosis (IHN) belonging to genus Novirhabdovirus (Rhabdoviridae). Economic losses caused by IHNV are serious in mainly Oncorhynchus spp. including rainbow trout O. mykiss and Atrantic salmon Salmo salar. IHNV was initially found by endemic presence in U.S. West Coast for sockeye salmon fry O. nerka and chinook salmon fry O. tshawytscha in the 1950s, and it has spread to Japan, Korea and Taiwan in the 1970s, and also to Italy and France in the 1990s. Currently, IHNV is detectable in many parts of the world, including Russia and South America. Mortality due to IHNV infection in fish with ${\leq}0.5g$ of body weight reaches 60% to 100%, while the mortality reduces by fish growing. In recent years, onset of IHNV infection has increased also in fish with large sizes. Here, we introduce molecular epidemiology and virulence changes of IHNV in East Asia, furthermore, we discuss on future prospects in IHNV researches.

• Journal of fish pathology
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• v.6 no.2
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• pp.87-92
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• 1993

In February of 1990, an epizootic disease to masu salmon. Onchorynchus masou cultured at the hatchery of trout in Samchuk. Kwangwondo have broken out and induced heavy mortality. An infectious hematopoietic necrosis virus(IHNV) was isolated from diseased masu salmon fry by the use of fish cell line, CHSE-214. This IHNV isolated from masu salmon was compared with USA isolates of IHNV, SRCV and RB-76 by analysis of virion proteins in sodium dodecyl sulfate poly-acrylamide gel electrophoresis (SDS-PAGE) and neutralization tests with two monoclonal antibodies raised against SRCV(MAb SRCV/A4) and RB-76(MAb RB/B5). In the antigenicity and the size of structural proteins. this IHNV, SCS atrain was smilar to RB-76 belonged to the electropherotype I proposed by Hsu et al.(1986).

• Journal of fish pathology
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• v.23 no.1
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• pp.1-8
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• 2010

Infectious hematopoietic necrosis virus (IHNV) is the causative agent of IHN, one of the most serious viral diseases of salmonid fish. In this study, glycoprotein (G) gene nucleotide sequence of isolated IHNV RtWanju09 from Jeollabuk-do province was analyzed to evaluate their genetic relatedness to worldwide isolates. As the result, it was revealed that IHNV RtWanju09 isolate belongs to JRt Shizuoka lineage with IHNV RtPy91 and RtJe00. The genetic diversity of G gene between RtWanju09 isolate and RtPy91 isolate from Gangwon-do province was 1.77% and maximum nucleotide diversity among the JRt Shizuoka lineage in Korea was 3.03% during the past 20 years, supporting that the continuous evolution has been occurred among JRt Shizuoka isolates. It was believed that IHNV RtWanju09 isolate has been introduced by the movement of contaminated eggs with IHNV from Gangwon-do to Jeollabuk-do by the reason that the eyed eggs in Jeollabuk-do province used to be obtained from Gangwon-do province. In this study, the domestic transfer of IHNV was firstly investigated by the transfer history of eggs and the phylogenetic analysis using IHNV glycoprotein gene sequence.

• Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.32-38
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• 2001

Several molecular biological techniques have been used to detect virus rapidly and accurately, but these methods have limitations in the early stage of viral infection with very low concentration of virus. We compared the detection limits of IMS-PCR, Western blot and ELISA with infectious hematopoietic necrosis virus OHNV). Four antibodies, rabbit anti-IHNV polyclonal antibody, anti-IHNV nucleocapsid protein monoclonal antibody, anti-IHNV nucleocapsid protein polyclonal antibody, and anti-IHNV glycoprotein polyclonal antibody, were tested to find out the most effective antibody for each method. The detection limit with IMS- PCR was $2\times10^6$ pfu when the viral RNA was extracted before RT-PCR. In the western blot with rabbit anti­IHNV polyclonal antibody one pfu of virus could be detected. In ELISA, 10 pfu of virus particles were detected with the same antibody.