1.Production and Storage of Virus Simulants.
In Sun SHIN ; Doyeong KIM ; Sung Jun YANG ; Byoung Chul LIM ; Younggil CHA ; Seongjoo KIM ; Tae Ju CHO
Journal of Bacteriology and Virology 2018;48(2):37-48
We have examined isolation and identification protocols for three virus simulant candidates to biological warfare agents. MS2 phage, a simulant for yellow fever virus and Hantaan virus, was propagated using as a host an E. coli strain with F pilus. MS2 phage genome was examined by reverse transcription and polymerase chain reaction (RT-PCR). Coat protein of the phage preparation was examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and mass spectrometric analysis. Cydia pomonella granulosis virus (CpGV) is a virus simulant candidate to smallpox virus. CpGV was isolated from a commercialized CpGV pellet. In this study, we developed new isolation and identification protocols for CpGV. One disadvantage of using CpGV is that it is not easy to determine viability of the virus. Here, we have included T4 phage as an alternative. We established a high titer production protocol and developed an easy genome identification protocol that does not require purified phage DNA. Stability of these virus preparations was also examined under various storage conditions. When the virus preparations were not subjected to freeze drying, MS2 phage was most stable when it was stored in liquid nitrogen but unstable at 4℃. In contrast, T4 phage was most stable when it was stored at 4℃. CpGV was stable at −20℃ but not at 4℃. Stability during or after freeze drying was also investigated. The result showed that 70~80% MS2 survived the freeze drying process. In contrast, only about 15% of T4 phage survived during the freeze drying. CpGV was found to be degraded during freeze drying.
Bacteriophage T4
;
Bacteriophages
;
Biological Warfare Agents
;
DNA
;
Electrophoresis
;
Freeze Drying
;
Genome
;
Granulovirus
;
Hantaan virus
;
Levivirus
;
Nitrogen
;
Polymerase Chain Reaction
;
Reverse Transcription
;
Variola virus
;
Yellow fever virus
2.Development and Characterization of Synthetic Norovirus RNA for Use in Molecular Detection Methods
Eun-Jung CHO ; Younggil CHA ; Su Kyung LEE ; Han-Sung KIM ; Jae-Seok KIM ; Eun Jin LEE ; Nuri LEE ; Ki Ho HONG ; Hee Jin HUH ; Young Joo CHA ; Hyun Soo KIM
Annals of Laboratory Medicine 2023;43(1):38-44
Background:
Reference materials are essential for the quality assurance of molecular detection methods. We developed and characterized synthetic norovirus GI and GII RNA reference materials.
Methods:
Norovirus GI and GII RNA sequences including the ORF1–ORF2 junction region were designed based on 1,495 reported norovirus sequences and synthesized via plasmid preparation and in vitro transcription. The synthetic norovirus GI and GII RNAs were evaluated using six commercial norovirus detection kits used in Korea and subjected to homogeneity and stability analyses. A multicenter study involving five laboratories and using four commercial real-time PCR norovirus detection assays was conducted for synthetic norovirus RNA characterization and uncertainty measurements.
Results:
The synthetic norovirus GI and GII RNAs were positively detected using the six commercial norovirus detection kits and were homogeneous and stable for one year when stored at –20°C or –70°C. All data from the five laboratories were within a range of 1.0 log copies/μL difference for each RNA, and the overall mean concentrations for norovirus GI and GII RNAs were 7.90 log copies/μL and 6.96 log copies/μL, respectively.
Conclusions
The synthetic norovirus GI and GII RNAs are adequate for quality control based on commercial molecular detection reagents for noroviruses with high sequence variability. The synthetic RNAs can be used as reference materials in norovirus molecular detection methods.
3.Obesity Exacerbates Coxsackievirus Infection via Lipid-Induced Mitochondrial Reactive Oxygen Species Generation
Seong-Ryeol KIM ; Jae-Hyoung SONG ; Jae-Hee AHN ; Myeong Seon JEONG ; Yoon Mee YANG ; Jaewon CHO ; Jae-Hyeon JEONG ; Younggil CHA ; Kil-Nam KIM ; Hong Pyo KIM ; Sun-Young CHANG ; Hyun-Jeong KO
Immune Network 2022;22(2):e19-
Coxsackievirus B3 (CVB3) infection causes acute pancreatitis and myocarditis. However, its pathophysiological mechanism is unclear. Here, we investigated how lipid metabolism is associated with exacerbation of CVB3 pathology using high-fat diet (HFD)-induced obese mice. Mice were intraperitoneally inoculated with 1×10 6 pfu/mouse of CVB3 after being fed a control or HFD to induce obesity. Mice were treated with mitoquinone (MitoQ) to reduce the level of mitochondrial ROS (mtROS). In obese mice, lipotoxicity of white adipose tissue-induced inflammation caused increased replication of CVB3 and mortality.The coxsackievirus adenovirus receptor increased under obese conditions, facilitating CVB3 replication in vitro. However, lipid-treated cells with receptor-specific inhibitors did not reduce CVB3 replication. In addition, lipid treatment increased mitochondria-derived vesicle formation and the number of multivesicular bodies. Alternatively, we found that inhibition of lipid-induced mtROS decreased viral replication. Notably, HFD-fed mice were more susceptible to CVB3-induced mortality in association with increased levels of CVB3 replication in adipose tissue, which was ameliorated by administration of the mtROS inhibitor, MitoQ. These results suggest that mtROS inhibitors can be used as potential treatments for CVB3 infection.