BACKGROUND: Only 39% was the positive predictive value of anti-hepatitis C virus (HCV) antibody test done by Korean Red Cross. Supplemental enzyme immunoassay (EIA) by another EIA kit may be also effective for reporting the more correct result to donors, instead of expensive supplemental immunoblot test. METHODS: All repeatedly reactive blood samples by EIA from 16 regional blood centers were retested for anti-HCV antibody by Abbott IMx HCV kit and LG HCD CONFIRM immunoblot kit. Presence of viral RNA was also confirmed using Amplicor HCV TEST kit from 180 samples, which were proportionately selected according to supplemental EIA and Immunoblot results. RESULTS: Of 2,211 repeatedly reactive samples, 909 samples (41%) were reactive and 1,302 (59%) samples were non-reactive with IMx HCV kit. 81% of reactive samples also showed positive pattern on the LG HCD CONFIRM strips and 79% of 1,302 samples showed negative pattern. RNA positivity was estimated 66% and 17% in Abbott IMx HCV positive and negative samples respectively, and 72%, 6%, 20% in LG HCD CONFIRM positive, indeterminate and negative samples respectively. CONCLUSION: HCV RNA positivity in positive samples by Abbott IMx HCV or LG HCD CONFIRM was not statistically significant (z=0.57 < 1.96, alpha=0.05). RNA detection rate by Abbott IMx HCV or LG HCD CONFIRM among HCV RNA positive samples, which was estimated as 73%, 70% respectively, was also statistically insignificant (z=0.375 < 1.96, alpha=0.05). So, it seems to be a good and economical practice that donors are notified of anti-HCV antibody results after supplemental EIA test using Abbott IMx HCV kit.
Humans ; Immunoenzyme Techniques* ; Red Cross ; RNA ; RNA, Viral ; Tissue Donors*

Native turnip yellow mosaic virus (TYMV) is relatively unreactive to maleimide agents, indicating few reactive thiol groups on TYMV. In the present study, we aimed to construct TYMV mutants that have reactive cysteine residues on the surface. To this end, we prepared a library of TYMV mutants where the Thr residue at the C-terminus of coat protein (CP) was replaced by a random sequence of six amino acids that included one cysteine. This library was introduced into Nicotiana benthamiana by agroinfiltration. The CP sequence of the TYMV RNA isolated from inoculated leaves was amplified by reverse transcription-PCR and then used to construct a second library. This process was repeated one more time, and the CP sequences of the TYMV RNA in the inoculated leaves were analyzed. Based on the analysis of over 11,000 CP sequences, the Cys mutants representing most abundant TYMV RNAs were constructed. Analysis of the mutants showed that four Cys mutants were nearly comparable to wildtype with respect to CP and viral RNA levels in N. benthamiana. All these mutants were highly reactive to fluoresceine-5-maleimide. This demonstrates that TYMV can be modified to have additional functional groups on the surface that would be useful for drug delivery.
Amino Acids ; Brassica napus* ; Cysteine ; RNA ; RNA, Viral ; Tobacco ; Tymovirus*

Chikungunya virus ; genetics ; isolation & purification ; China ; Genome, Viral ; RNA, Viral ; genetics ; Sequence Analysis, RNA

RNA interference (RNAi) is one of the important mechanisms to regulate gene expression in eukaryotes. One of the original functions of RNAi is to facilitate the antiviral strategy of host. Early studies reveal that invertebrates can use RNAi to resist viruses. However, if this mechanism exists in mammals is still controversial. The latest studies confirm that mammals do have the RNAi-based immunity, and researchers believe that RNAi-based antiviral immunity is a brand-new immunological mechanism that was neglected in the past. It is worthy to note that virus can also use RNAi to enhance its infectivity and immune escape in host cells. This review introduces the research history of RNAi-based antiviral immunity in animals and summarizes the main findings in this field. Last but not least, we indicate a series of unresolved questions about RNAi-based antiviral immunity, and explore the relationship between RNAi-based antiviral immunity and other innate immunological pathways. The virus-mediated RNAi pathway in animal is not only an interesting basic biology question, but also has important guiding roles in the development of antiviral drugs.
Animals ; Antiviral Agents ; Immunity, Innate/genetics* ; Mammals ; RNA Interference ; RNA, Small Interfering/genetics* ; RNA, Viral

China ; Enterovirus ; classification ; genetics ; Phylogeny ; RNA, Viral ; genetics

COVID-19 ; Humans ; RNA, Viral ; Risk Factors ; SARS-CoV-2

Epstein-Barr virus(EBV) has been implicated in the pathogenesis of B-lymphoproliferative disorders, T-cell lymphomas and Hodgkin's disease. In this report, we performed an in situ hybridization study on EBV genome in 10 cases of nasal non-Hodgkin's lymphoma(NHL), 20 cases of Waldeyer's ring(WR) NHL, and 20 cases of nodal NHLs to document EBV association with lymphomas in Koreans. For immunophenotyping, monoclonal antibodies for CD 20, MB 2, CD 45Ro & CD 43 were used. For in situ hybridization study, EBV DNA probe for Bam HI 'V' fragment and EBV RNA probe for EBER and BHLF were used. Twenty two cases(44%) of malignant lymphomas were positive for EBV genome. Generally, T-cell lymphomas showed a higher positive rate(61%) than B-cell lymphomas(24%). Among T-cell lymphomas, nasal lymphomas showed a higher positive rate(80%) than WR(50%) or nodal lymphomas(50%). Of 22 EBV genome positive cases, 10 cases were positive for EBER, 10 cases for BHLF, and 2 cases for both EBER and BHLF. The histologic types by Working Formulation(WF) were not correlated with EBV genome positive rate, whereas lymphomas showing the histologic spectrum of polymorphic reticulosis(PR) showed a higher positive rate(65%) than lymphomas without PR-like features(40%). These results indicate that nasal T-cell lymphomas with the histologic spectrum of PR are strongly associated with EBV and that the anatomic site may be an important factor in this association.
DNA, Viral/analysis ; Genome, Viral ; Herpesvirus 4, Human/*genetics ; Human ; *In Situ Hybridization ; Lymphoma, Non-Hodgkin/*virology ; RNA, Viral/analysis

Influenza B virus ; genetics ; pathogenicity ; Phylogeny ; RNA, Viral ; genetics ; Viral Nonstructural Proteins ; genetics

China ; DNA, Viral ; blood ; Hepacivirus ; classification ; Hepatitis C ; diagnosis ; etiology ; therapy ; Humans ; RNA, Viral ; analysis

Genome, Viral ; Hepacivirus ; genetics ; physiology ; Models, Biological ; RNA, Viral ; biosynthesis ; genetics ; Replicon ; Transformation, Genetic ; Virus Replication