Preparation of a Chimeric Armored RNA as a Versatile Calibrator for Multiple Virus Assays

AbstractAs the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic was expanding, it was clear that effective testing for the presence of neutralizing antibodies in the blood of convalescent patients would be critical for development of plasma-based therapeutic approaches. To address the need for a high-quality neutralization assay against SARS-CoV-2, a previously established fluorescence reduction neutralization assay (FRNA) against Middle East respiratory syndrome coronavirus (MERS-CoV) was modified and optimized. The SARS-CoV-2 FRNA provides a quantitative assessment of a large number of infected cells through use of a high-content imaging system. Because of this approach, and the fact that it does not involve subjective interpretation, this assay is more efficient and more accurate than other neutralization assays. In addition, the ability to set robust acceptance criteria for individual plates and specific test wells provided further rigor to this assay. Such agile adaptability avails use with multiple virus variants. By February 2021, the SARS-CoV-2 FRNA had been used to screen over 5,000 samples, including acute and convalescent plasma or serum samples and therapeutic antibody treatments, for SARS-CoV-2 neutralizing titers.

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INTRODUCTION TO QUANTAL VIRUS ASSAYS

Virology ◽

10.1016/b978-0-12-144730-4.50014-x ◽

1992 ◽

pp. 53-57 ◽

Cited By ~ 8

Author(s):

FLORENCE G. BURLESON ◽

THOMAS M. CHAMBERS ◽

DANNY L. WIEDBRAUK

Keyword(s):

Virus Assays

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Preparation of His-Tagged Armored RNA particles as positive controls for Real-Time RT-PCR Detection of Zika virus

Tạp chí Y học Dự phòng ◽

10.51403/0868-2836/2021/332 ◽

2021 ◽

Vol 31 (4) ◽

pp. 18-27

Author(s):

Do Thi Quynh Nga ◽

Ha Thi Phuong Mai ◽

Tran Thi Hai Au ◽

Vu Thi Kim Lien ◽

Vu Thi Bich Hau ◽

...

Keyword(s):

Real Time ◽

Zika Virus ◽

Room Temperature ◽

Virus Detection ◽

Positive Control ◽

Reverse Transcription Pcr ◽

His Tag ◽

Armored Rna ◽

Genomic Regions ◽

Positive Controls

Armored RNA (AR) is a good candidate for creating nuclease-resistant RNA positive controls in the nucleic acid - based assay for RNA viruses. To simplify the production and purifcation of armored RNA, a single plasmid double – expressing His6-tag system was designed. His-tag armored RNA particles were purifed using his-tag affnity. A genomic fragment of the zika virus consisting of the encoding sequences of ﬂavi-M, ﬂavi-E-C protein targeted for zika virus was selected to prepare a positive control. In this study, we have successfully produced His-taged MS2- phage like particles carrying specifc genomic regions (M and E genes) to monitor the procedures of real-time Reverse transcription-PCR for Zika virus detection in one plasmid double expression. AR-ZIKA is completely resistant to DNase and RNase, stable in normal human EDTA plasma at room temperature for at least 60 and 15 days at 40C and room temperature respectively.

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Most viral peptides displayed by class I MHC on infected cells are immunogenic

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1815239116 ◽

2019 ◽

Vol 116 (8) ◽

pp. 3112-3117 ◽

Cited By ~ 34

Author(s):

Nathan P. Croft ◽

Stewart A. Smith ◽

Jana Pickering ◽

John Sidney ◽

Bjoern Peters ◽

...

Keyword(s):

Infected Mouse ◽

High Resolution Mass Spectrometry ◽

Peptide Sequencing ◽

Class I ◽

Class I Mhc ◽

Wide Range ◽

Multiple Virus ◽

Infected Cells ◽

High Fraction ◽

Mouse Cells

CD8+ T cells are essential effectors in antiviral immunity, recognizing short virus-derived peptides presented by MHC class I (pMHCI) on the surface of infected cells. However, the fraction of viral pMHCI on infected cells that are immunogenic has not been shown for any virus. To approach this fundamental question, we used peptide sequencing by high-resolution mass spectrometry to identify more than 170 vaccinia virus pMHCI presented on infected mouse cells. Next, we screened each peptide for immunogenicity in multiple virus-infected mice, revealing a wide range of immunogenicities. A surprisingly high fraction (>80%) of pMHCI were immunogenic in at least one infected mouse, and nearly 40% were immunogenic across more than half of the mice screened. The high number of peptides found to be immunogenic and the distribution of responses across mice give us insight into the specificity of antiviral CD8+ T cell responses.

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Controlling Avian Influenza Virus in Bangladesh: Challenges and Recommendations

Viruses ◽

10.3390/v12070751 ◽

2020 ◽

Vol 12 (7) ◽

pp. 751

Author(s):

Rokshana Parvin ◽

Mohammed Nooruzzaman ◽

Congriev Kumar Kabiraj ◽

Jahan Ara Begum ◽

Emdadul Haque Chowdhury ◽

...

Keyword(s):

Influenza Virus ◽

Avian Influenza ◽

Avian Influenza Virus ◽

Control Strategies ◽

Poultry Production ◽

New Host ◽

Multiple Virus ◽

Virus Spreading ◽

Virus Strains ◽

New Host Species

Avian influenza virus (AIV) remains a huge challenge for poultry production with negative repercussions for micro- and macro-economy and public health in Bangladesh. High (HP) H5N1 and low pathogenicity (LP) H9N2 AIV are currently endemic in poultry, and both have been reported to infect humans sporadically. Multiple virus introductions of different clades of HPAIV H5N1, reassorted genotypes, and on-going diversification of LPAIV H9N2 create a highly volatile virological environment which potentially implicates increased virulence, adaptation to new host species, and subsequent zoonotic transmission. Allotropy of poultry rearing systems and supply chains further increase the risk of virus spreading, which leads to human exposure and fosters the emergence of new potentially pre-pandemic virus strains. Here, we review the epidemiology, focusing on (i) risk factors for virus spreading, (ii) viral genetic evolution, and (iii) options for AIV control in Bangladesh. It is concluded that improved control strategies would profit from the integration of various intervention tools, including effective vaccination, enhanced biosecurity practice, and improved awareness of producers and traders, although widespread household poultry rearing significantly interferes with any such strategies. Nevertheless, continuous surveillance associated with rapid diagnosis and thorough virus characterization is the basis of such strategies.

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