Isolation, sequence, infectivity and replication kinetics of SARS-CoV-2

Abstract

24SARS-CoV-2 emerged in December 2019 in Wuhan, China and has since infected over 1.5 25 million people, of which over 107,000 have died. As SARS-CoV-2 spreads across the planet, 26 speculations remain about the range of human cells that can be infected by SARS-CoV-2. In this 27 study, we report the isolation of SARS-CoV-2 from two cases of COVID-19 in Toronto, Canada. 28We determined the genomic sequences of the two isolates and identified single nucleotide 29 changes in representative populations of our virus stocks. More importantly, we tested a wide 30 range of human immune cells for productive infection with SARS-CoV-2. Here we confirm that 31 human primary peripheral blood mononuclear cells (PBMCs) are not permissive for SARS-CoV-32 2. As SARS-CoV-2 continues to spread globally, it is essential to monitor single nucleotide 33 polymorphisms in the virus and to continue to isolate circulating viruses to determine viral 34 genotype and phenotype using in vitro and in vivo infection models. 35

Experimental and natural evidence of SARS-CoV-2-infection-induced activation of type I interferon responses

“…HSV-GFP stocks were generated and maintained as mentioned previously (Minaker et al, 2005). Clinical isolate of SARS-CoV-2 (SARS-CoV-2/SB3) was propagated on Vero E6 cells and validated by next-generation sequencing (Banerjee et al, 2020a). Virus stocks were thawed once and used for an experiment.…”

“…Vero E6 cells (African green monkey cells; ATCC) were maintained in Dulbecco's modified Eagle's media (DMEM) supplemented with 10% fetal bovine serum (FBS; Sigma-Aldrich), 1x L-Glutamine, and Penicillin/ Streptomycin (Pen/Strep; VWR) (Banerjee et al, 2020a). Calu-3 cells (human male lung adenocarcinoma derived; ATCC) were cultured as previously mentioned (Aguiar et al, 2019 iScience Article time, normalized transcript counts were used to perform differential-expression analysis with DESeq2.…”

“…In this study, we have identified global early transcriptional responses that are initiated during infection of human airway epithelial (Calu-3) cells at 0, 1, 2, 3, 6, and 12 h post incubation with a clinical isolate of SARS-CoV-2 from a COVID-19 patient in Toronto (Banerjee et al, 2020a). Data from our study demonstrate that SARS-CoV-2 infection induces the expression of type I IFNs, along with the expression of downstream ISGs.…”

Coinfection with SARS‐CoV‐2 and other respiratory pathogens in patients with COVID‐19 in Guangzhou, China

“…microscopy 14. Sepsis leads to large amounts of proinflammatory and anti-inflammatory cytokines, which induce reduced lymphocyte apoptosis and chronic immune responses 15.…”

BTK/ITK dual inhibitors: Modulating immunopathology and lymphopenia for COVID-19 therapy

“…This speculation is further supported by recent findings that SARS-CoV-2 is able to enter human T cells, although replication inside T cells was not observed (as determined via RT-qPCR with probes targeting the viral Nucleocapsid, 5 ′ UTR, or Envelope genes). 12,13 Despite the apparent lack of viral genome replication, the SARS-CoV-2 nucleocapsid protein can persist within T cells up to 24 h postinfection 13 ; and viral particles could be observed via electron microscopy in SARS-CoV-2-infected primary PBMCs (from healthy donors) in CD4 + T cells but not CD8 + T cells, at 48 h post in vitro infection. 12 Given that this was observed with PBMCs infected in vitro, further studies are required to determine whether this represents a true preference in COVID-19.…”