OmniVira

Q493K and Q498H substitutions in Spike promote adaptation of SARS-CoV-2 in mice.

Kun Huang1,2,3 Yufei Zhang1,2,3 Xianfeng Hui1,2,3 Ya Zhao1,2,3 Wenxiao Gong1,2,3 Ting Wang1,2,3 Shaoran Zhang4 Yong Yang1,2,3 Fei Deng5 Qiang Zhang1,2,3 Xi Chen6 Ying Yang1,2,3 Xiaomei Sun1,2,3 Huanchun Chen1,6 Yizhi J Tao7 Zhong Zou1,2,8 Meilin Jin1,2,9
Affiliations 9 institutions
  1. State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China
  2. College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China
  3. Key Laboratory of development of veterinary diagnostic products, Ministry of Agriculture, Wuhan, 430070, PR China.
  4. State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
  5. State Key Laboratory of Virology and National Virus Resource Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, PR China.
  6. College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China.
  7. Department of BioSciences, Rice University, Houston, TX 77005, USA.
  8. Key Laboratory of development of veterinary diagnostic products, Ministry of Agriculture, Wuhan, 430070, PR China. Electronic address: [email protected].
  9. Key Laboratory of development of veterinary diagnostic products, Ministry of Agriculture, Wuhan, 430070, PR China. Electronic address: [email protected].
PMID33993052 DOI10.1016/j.ebiom.2021.103381 Year2021 Journal EBioMedicine Languageeng Statusppublish

Abstract

An ideal animal model to study SARS-coronavirus 2 (SARS-CoV-2) pathogenesis and evaluate therapies and vaccines should reproduce SARS-CoV-2 infection and recapitulate lung disease like those seen in humans. The angiotensin-converting enzyme 2 (ACE2) is a functional receptor for SARS-CoV-2, but mice are resistant to the infection because their ACE2 is incompatible with the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein . SARS-CoV-2 was passaged in BALB/c mice to obtain mouse-adapted virus strain. Complete genome deep sequencing of different generations of viruses was performed to characterize the dynamics of the adaptive mutations in SARS-CoV-2. Indirect immunofluorescence analysis and Biolayer interferometry experiments determined the binding affinity of mouse-adapted SARS-CoV-2 WBP-1 RBD to mouse ACE2 and human ACE2. Finally, we tested whether TLR7/8 agonist Resiquimod (R848) could also inhibit the replication of WBP-1 in the mouse model. The mouse-adapted strain WBP-1 showed increased infectivity in BALB/c mice and led to severe interstitial pneumonia. We characterized the dynamics of the adaptive mutations in SARS-CoV-2 and demonstrated that Q493K and Q498H in RBD significantly increased its binding affinity towards mouse ACE2. Additionally, the study tentatively found that the TLR7/8 agonist Resiquimod was able to protect mice against WBP-1 challenge. Therefore, this mouse-adapted strain is a useful tool to investigate COVID-19 and develop new therapies. We found for the first time that the Q493K and Q498H mutations in the RBD of WBP-1 enhanced its interactive affinities with mACE2. The mouse-adapted SARS-CoV-2 provides a valuable tool for the evaluation of novel antiviral and vaccine strategies. This study also tentatively verified the antiviral activity of TLR7/8 agonist Resiquimod against SARS-CoV-2 in vitro and in vivo. This research was funded by the National Key Research and Development Program of China (2020YFC0845600) and Emergency Science and Technology Project of Hubei Province (2020FCA046) and Robert A. Welch Foundation (C-1565).

Supporting text Virus Host Location
Adaptive mutations 3 Angiotensin-converting enzyme 2 179 Mouse-adapted strain 2 SARS-CoV-2 550 TLR7/8 agonist 1 Amino Acid Substitution 81 Adaptation, Physiological 33 Angiotensin-Converting Enzyme 2 177 Animals 1948 Binding Sites 89 Caco-2 Cells 3 Chlorocebus aethiops 70 COVID-19 425 Disease Models, Animal 77 Female 289 High-Throughput Nucleotide Sequencing 39 Humans 1440 Imidazoles 1 Mice 253 Mice, Inbred BALB C 73 SARS-CoV-2 453 Serial Passage 9 Spike Glycoprotein, Coronavirus 274 Vero Cells 55

Evidence records

2 total
Experimental Infection
1 records · 1 evidence types
Evidence type Pathogenicity Experiment
1 records
OVE4790 Pathogenicity Experiment
Key finding

Mouse-adapted SARS-CoV-2 strain WBP-1 caused severe interstitial pneumonia and showed increased infectivity in BALB/c mice.

Virus
Severe acute respiratory syndrome coronavirus 2
Host
house mouse Mus musculus Experimental system
Location
Not specified
Supporting text

The mouse-adapted strain WBP-1 showed increased infectivity in BALB/c mice and led to severe interstitial pneumonia.

Method
experimental infection | histopathology | clinical observation
Experimental system
mouse infection model
Functional Mechanism
1 records · 1 evidence types
Evidence type Molecular Adaptation
1 records
OVE4788 Molecular Adaptation
Key finding

Q493K and Q498H substitutions in the SARS-CoV-2 spike RBD increased binding affinity to mouse ACE2, promoting adaptation to mice.

Virus
Severe acute respiratory syndrome coronavirus 2
Host
Not specified
Location
Not specified
Supporting text

We characterized the dynamics of the adaptive mutations in SARS-CoV-2 and demonstrated that Q493K and Q498H in RBD significantly increased its binding affinity towards mouse ACE2.

Genes or proteins
spike | RBD
Receptors
mouse ACE2
Mutations
Q493K | Q498H
Mechanism types
receptor binding | host-range expansion