tetano
Editor, Senior Moderator
J Virol
. 2021 Jun 16;JVI0040221.
doi: 10.1128/JVI.00402-21. Online ahead of print.
Contribution of SARS-CoV-2 accessory proteins to viral pathogenicity in K18 hACE2 transgenic mice
Jesus A Silvas[SUP] 1 [/SUP], Desarey Morales Vasquez[SUP] 1 [/SUP], Jun-Gyu Park[SUP] 1 [/SUP], Kevin Chiem[SUP] 1 [/SUP], Anna Allué-Guardia[SUP] 1 [/SUP], Andreu Garcia-Vilanova[SUP] 1 [/SUP], Roy Neal Platt[SUP] 1 [/SUP], Lisa Miorin[SUP] 2 3 [/SUP], Thomas Kehrer[SUP] 2 3 4 [/SUP], Anastasija Cupic[SUP] 2 3 [/SUP], Ana S Gonzalez-Reiche[SUP] 5 [/SUP], Harm van Bakel[SUP] 5 [/SUP], Adolfo García-Sastre[SUP] 2 3 6 7 [/SUP], Tim Anderson[SUP] 1 [/SUP], Jordi B Torrelles[SUP] 1 [/SUP], Chengjin Ye[SUP] 1 [/SUP], Luis Martinez-Sobrido[SUP] 1 [/SUP]
Affiliations
Abstract
Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) is the viral pathogen responsible for the current coronavirus disease 2019 (COVID-19) pandemic. As of May 19[SUP]th[/SUP] 2021, John Hopkins University's COVID-19 tracking platform has reported 3.3 million deaths associated with SARS-CoV-2 infection. Currently, the World Health Organization has granted emergency use listing (EUL) to six COVID-19 vaccines candidates. However much of the pathogenesis observed during SARS-CoV-2 infection remains elusive. To gain insight into the contribution of individual accessory open reading frame (ORF) proteins in SARS-CoV-2 pathogenesis, we used our recently described reverse genetics system approach to successfully engineer recombinant (r)SARS-CoV-2, where we individually removed viral 3a, 6, 7a, 7b, and 8 ORF proteins, and characterized these recombinant viruses in vitro and in vivo. Our results indicate differences in plaque morphology, with ORF deficient (ΔORF) viruses producing smaller plaques than those of the wild-type (rSARS-CoV-2/WT). However, growth kinetics of ΔORF viruses were like those of rSARS-CoV-2/WT. Interestingly, infection of K18 human angiotensin converting enzyme 2 (hACE2) transgenic mice with the ΔORF rSARS-CoV-2 identified ORF3a and ORF6 as the major contributors of viral pathogenesis, while ΔORF7a, ΔORF7b and ΔORF8 rSARS-CoV-2 induced comparable pathology to rSARS-CoV-2/WT. This study demonstrates the robustness of our reverse genetics system to generate rSARS-CoV-2 and the major role for ORF3a and ORF6 in viral pathogenesis, providing important information for the generation of attenuated forms of SARS-CoV-2 for their implementation as live-attenuated vaccines for the treatment of SARS-CoV-2 infection and associated COVID-19. IMPORTANCE Despite great efforts put forward worldwide to combat the current coronavirus disease 2019 (COVID-19) pandemic, Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) continues to be a human health and socioeconomic threat. Insights into the pathogenesis of SARS-CoV-2 and contribution of viral proteins to disease outcome remains elusive. Our study aims to determine the contribution of SARS-CoV-2 accessory open reading frame (ORF) proteins in viral pathogenesis and disease outcome, and develop a synergistic platform combining our robust reverse genetics system to generate recombinant (r)SARS-CoV-2 with a validated rodent model of infection and disease. We demonstrated that SARS-CoV-2 ORF3a and ORF6 contribute to lung pathology and ultimately disease outcome in K18 hACE2 transgenic mice, while ORF7a, ORF7b, and ORF8 have little impact on disease outcome. Moreover, our combinatory platform serves as the foundation to generate attenuated forms of the virus to develop live-attenuated vaccines for the treatment of SARS-CoV-2.
. 2021 Jun 16;JVI0040221.
doi: 10.1128/JVI.00402-21. Online ahead of print.
Contribution of SARS-CoV-2 accessory proteins to viral pathogenicity in K18 hACE2 transgenic mice
Jesus A Silvas[SUP] 1 [/SUP], Desarey Morales Vasquez[SUP] 1 [/SUP], Jun-Gyu Park[SUP] 1 [/SUP], Kevin Chiem[SUP] 1 [/SUP], Anna Allué-Guardia[SUP] 1 [/SUP], Andreu Garcia-Vilanova[SUP] 1 [/SUP], Roy Neal Platt[SUP] 1 [/SUP], Lisa Miorin[SUP] 2 3 [/SUP], Thomas Kehrer[SUP] 2 3 4 [/SUP], Anastasija Cupic[SUP] 2 3 [/SUP], Ana S Gonzalez-Reiche[SUP] 5 [/SUP], Harm van Bakel[SUP] 5 [/SUP], Adolfo García-Sastre[SUP] 2 3 6 7 [/SUP], Tim Anderson[SUP] 1 [/SUP], Jordi B Torrelles[SUP] 1 [/SUP], Chengjin Ye[SUP] 1 [/SUP], Luis Martinez-Sobrido[SUP] 1 [/SUP]
Affiliations
- PMID: 34133899
- DOI: 10.1128/JVI.00402-21
Abstract
Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) is the viral pathogen responsible for the current coronavirus disease 2019 (COVID-19) pandemic. As of May 19[SUP]th[/SUP] 2021, John Hopkins University's COVID-19 tracking platform has reported 3.3 million deaths associated with SARS-CoV-2 infection. Currently, the World Health Organization has granted emergency use listing (EUL) to six COVID-19 vaccines candidates. However much of the pathogenesis observed during SARS-CoV-2 infection remains elusive. To gain insight into the contribution of individual accessory open reading frame (ORF) proteins in SARS-CoV-2 pathogenesis, we used our recently described reverse genetics system approach to successfully engineer recombinant (r)SARS-CoV-2, where we individually removed viral 3a, 6, 7a, 7b, and 8 ORF proteins, and characterized these recombinant viruses in vitro and in vivo. Our results indicate differences in plaque morphology, with ORF deficient (ΔORF) viruses producing smaller plaques than those of the wild-type (rSARS-CoV-2/WT). However, growth kinetics of ΔORF viruses were like those of rSARS-CoV-2/WT. Interestingly, infection of K18 human angiotensin converting enzyme 2 (hACE2) transgenic mice with the ΔORF rSARS-CoV-2 identified ORF3a and ORF6 as the major contributors of viral pathogenesis, while ΔORF7a, ΔORF7b and ΔORF8 rSARS-CoV-2 induced comparable pathology to rSARS-CoV-2/WT. This study demonstrates the robustness of our reverse genetics system to generate rSARS-CoV-2 and the major role for ORF3a and ORF6 in viral pathogenesis, providing important information for the generation of attenuated forms of SARS-CoV-2 for their implementation as live-attenuated vaccines for the treatment of SARS-CoV-2 infection and associated COVID-19. IMPORTANCE Despite great efforts put forward worldwide to combat the current coronavirus disease 2019 (COVID-19) pandemic, Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) continues to be a human health and socioeconomic threat. Insights into the pathogenesis of SARS-CoV-2 and contribution of viral proteins to disease outcome remains elusive. Our study aims to determine the contribution of SARS-CoV-2 accessory open reading frame (ORF) proteins in viral pathogenesis and disease outcome, and develop a synergistic platform combining our robust reverse genetics system to generate recombinant (r)SARS-CoV-2 with a validated rodent model of infection and disease. We demonstrated that SARS-CoV-2 ORF3a and ORF6 contribute to lung pathology and ultimately disease outcome in K18 hACE2 transgenic mice, while ORF7a, ORF7b, and ORF8 have little impact on disease outcome. Moreover, our combinatory platform serves as the foundation to generate attenuated forms of the virus to develop live-attenuated vaccines for the treatment of SARS-CoV-2.