Cited by 649SARS-CoV-2 and COVID-19 ResearchAnimal Virus Infections StudiesSARS-CoV-2 detection and testing

An Infectious cDNA Clone of SARS-CoV-2

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Xie, Xuping, Muruato, Antonio, Lokugamage, Kumari G., Narayanan, Krishna, Zhang, Xianwen, Zou, Jing, Liu, Jianying, Schindewolf, Craig +8 more·2020·Cell Host & Microbe

Abstract

The ongoing pandemic of COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), underscores the urgency to develop experimental systems for studying this virus and identifying countermeasures. We report a reverse genetic system for SARS-CoV-2. Seven complimentary DNA (cDNA) fragments spanning the SARS-CoV-2 genome were assembled into a full-genome cDNA. RNA transcribed from the full-genome cDNA was highly infectious after electroporation into cells, producing 2.9 × 10 6 plaque-forming unit (PFU)/mL of virus. Compared with a clinical isolate, the infectious-clone-derived SARS-CoV-2 (icSARS-CoV-2) exhibited similar plaque morphology, viral RNA profile, and replication kinetics. Additionally, icSARS-CoV-2 retained engineered molecular markers and did not acquire other mutations. We generated a stable mNeonGreen SARS-CoV-2 (icSARS-CoV-2-mNG) by introducing this reporter gene into ORF7 of the viral genome. icSARS-CoV-2-mNG was successfully used to evaluate the antiviral activities of interferon (IFN). Collectively, the reverse genetic system and reporter virus provide key reagents to study SARS-CoV-2 and develop countermeasures.

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Crossref · 10.1016/j.chom.2020.04.004

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  • Together with reports of preserved neutralization of SARS-CoV-2 with key B.1.1.7 and B.1.351 spike mutations and of pseudovirus with the full B.1.1.7 spike mutation set, our data indicate broad BNT162b2-elicited immune recognition.

    “Together with recent reports of the preserved neutralization of SARS-CoV-2 with key S mutations found in the B.1.1.7 and the B.1.351lineage 39,40 , and neutralization of pseudovirus bearing the full set of mutations of B.1.1.7 S 41 , our data indicate broad BNT162b2-elicited immune recognition 2,13,14 .”

    From BNT162b2 vaccine induces neutralizing antibodies and poly-specific T cells in humans (2021) · cites this paper as [40]

    The Results describe a SARS-CoV-2 infectious clone and mNeonGreen reporter virus, while the Introduction discusses their potential use in vaccine development. Our copy does not address BNT162b2-elicited immune recognition or neutralization of B.1.1.7 or B.1.351 mutations (searched: BNT162b2, variant neutralization, and neutralizing antibodies). (LLM, conf=0.75)

    Experimental — accuracy not yet measured
  • Two pseudovirus variants carried either eight or ten mutations found in the S protein of the B.1.351 lineage.

    “Two variants had either eight (D80A/D215G/Δ242-244/ K417N/E484K/N501Y/D614G/A701V) or ten mutations (L18F/D80A/ D215G/R246I/Δ242-244/K417N/E484K/N501Y/D614G/A701V) found in S of the B.1.351lineage (also referred to as 20C/501Y.V2) 40 .”

    From BNT162b2 vaccine induces neutralizing antibodies and poly-specific T cells in humans (2021) · cites this paper as [40]

    The Discussion describes an infectious SARS-CoV-2 clone and proposes using it to study future spike mutations; the Methods describe three silent marker mutations. Searches for B.1.351, pseudovirus variants, and the listed spike mutations found no passage in our copy addressing the claimed eight- or ten-mutation variants. The indexed passages provide no page numbers. (LLM, conf=0.76)

    Experimental — accuracy not yet measured
  • N501Y is located in the viral receptor-binding domain for cell entry and increases binding to the angiotensin-converting enzyme 2 receptor.

    “This mutation is located in the viral receptor-binding domain (RBD) for cell entry, increases binding to the angiotensin-converting enzyme 2 receptor”
  • N501Y enables the virus to expand its host range to infect mice.

    “and enables the virus to expand its host range to infect mice 5,6 .”

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Authors
Xie, X., Muruato, A., Lokugamage, K. G., Narayanan, K., Zhang, X., Zou, J., Liu, J., Schindewolf, C., Bopp, N. E., Aguilar, P. V., Plante, K. S., Weaver, S. C., Makino, S., LeDuc, J. W., Menachery, V. D., & Shi, P.-Y.
Affiliations
The University of Texas Medical Branch at Galveston (US)
Corresponding author
  • Xie, Xuping
  • Menachery, Vineet D.
  • Shi, Pei-Yong
Venue
Cell Host & Microbe
Publisher
Elsevier BV
Published
2020-05
Volume
27
Issue
5
Pages
841-848.e3
ISSN
1931-3128 (ISSN-L)
OpenAlex
W3015751519
Cited by
647
References
30
Citations by year
2026: 30 · 2025: 47 · 2024: 54 · 2023: 94 · 2022: 162 · 2021: 180 · 2020: 80
FWCI
16.94
Type
journal article
Language
en
Open access
Locations
  • Cell Host & Microbe (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • Centers for Disease Control and Prevention
  • National Institute on Aging
  • National Institute of Allergy and Infectious Diseases
  • Amon G. Carter Foundation
  • Summerfield G. Roberts Foundation
  • National Institutes of Health (5UC7AI094660, AI114657, AI146081, R00AG049092, R24AI120942, U19AI100625)
  • University of Texas Medical Branch
  • Gillson Longenbaugh Foundation
  • Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation
  • John S. Dunn Foundation
  • University of Texas System (AI127744, AI134907, AI136126, AI142759, AI145617, UL1TR001439)
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Animal Virus Infections Studies
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 detection and testing
Keywords
SARS-CoV-2, infectious clone, reverse genetics, reporter virus, ORF7, interferon antiviral activity, viral replication kinetics, plaque morphology, COVID-19 pandemic
MeSH terms
Betacoronavirus, COVID-19, SARS-CoV-2, Animals, Antiviral Agents, Chlorocebus aethiops, Clone Cells, Interferons, Pneumonia, Viral, RNA, Viral, Vero Cells, Virus Replication, Genome, Viral, Genes, Reporter, DNA, Complementary, Coronavirus Infections, Organisms, Genetically Modified, Pandemics

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