Project description:For the assessment of host response dynamics to SARS-CoV and SARS-CoV-2 infections in human airway epithelial cells at ambient temperature corresponding to the upper or lower respiratory tract. We performed a temporal transcriptome analysis on human airway epithelial cell (hAEC) cultures infected with SARS-CoV and SARS-CoV-2, as well as uninfected hAEC cultures, incubated either at 33°C or 37°C. hAEC cultures were harvested at 24, 48 72, 96 hpi and processed for Bulk RNA Barcoding and sequencing (BRB-seq), which allows a rapid and sensitive genome-wide transcriptomic analysis in a highly multiplexed manner. Transcriptome data was obtained from a total of 7 biological donors for pairwise comparisons of SARS-CoV or SARS-CoV-2 virus-infected to unexposed hAEC cultures at respective time points and temperatures.
Project description:The purpose of this study was to identify miRNAs that were dysregulated after the onset of COVID-19 and thus potentially be used for risk stratification (i.e., mortality). Therefore, we conducted a multi-center, retrospective longitudinal cohort study enrolling 142 patients with laboratory-confirmed SARS-CoV-2 infection who presented to two Canadian hospitals from May 2020 – December 2020 along with a cohort of 27 SARS-CoV-2 patients with mild upper respiratory tract symptoms and 69 SARS-CoV-2-negative patients from the ICU. Blood was biobanked from SARS-CoV-2 positive patients in the emergency department (mild), ward (moderate) or intensive care unit (severe). Assessment of miRNA expression and co-regulatory network generation revealed significant transcriptome dyregulation in pateints with severe COVID-19 that was largely different from SARS-CoV-2 negative patients in the ICU.
Project description:The purpose of this study was to identify mRNAs that were dysregulated after exposure to COVID-19 patient plasma and thus possibly contribute to vascular inflammation. Therefore, we conducted a multi-center, retrospective longitudinal cohort study enrolling 142 patients with laboratory-confirmed SARS-CoV-2 infection who presented to two Canadian hospitals from May 2020 – December 2020 along with a cohort of 27 SARS-CoV-2 patients with mild upper respiratory tract symptoms and 69 SARS-CoV-2-negative patients from the ICU. Blood was biobanked from SARS-CoV-2 positive patients in the emergency department (mild), ward (moderate) or intensive care unit (severe). Assessment of gene regulatory networks, gene set enrichment analysis, and in vitro permeability follow-up suggested functional reductions in junctional protein expression. Following this, confirmed critical reductions in VE-cadherin and ZO-1 which may drive pathology in moderate and severe cases of COVID-19.
Project description:The amount of SARS-CoV-2 detected in the upper respiratory tract (URT viral load) is a key driver of transmission of infection. Current evidence suggests that mechanisms constraining URT viral load are different from those controlling lower respiratory tract viral load and disease severity. Understanding such mechanisms may help to develop treatments and vaccine strategies to reduce transmission. Combining mathematical modelling of URT viral load dynamics with transcriptome analyses we aimed to identify mechanisms controlling URT viral load. COVID-19 patients were recruited in Spain during the first wave of the pandemic. RNA sequencing of peripheral blood and targeted NanoString nCounter transcriptome analysis of nasal epithelium were performed and gene expression analysed in relation to paired URT viral load samples collected within 15 days of symptom onset. Proportions of major immune cells in blood were estimated from transcriptional data using computational differential estimation. Weighted correlation network analysis (adjusted for cell proportions) and fixed transcriptional repertoire analysis were used to identify associations with URT viral load, quantified as standard deviations (z-scores) from an expected trajectory over time.
Project description:Full understanding of the pathophysiology of COVID-19 is critical for adequate treatment and development of vaccine and therapeutics. Although Golden hamster has been emerged as animal model of COVID-19, it is unknown how SARS-CoV-2 enters and infects targeted epithelial cells at molecular and cellular levels. Here, by applying single cell RNA sequencing in the upper respiratory tract, lung, kidney and intestine of golden hamster, we show that the expression profiles of host factors for SARS-CoV-2 infection in specific cell types are similar to that of human. These data can be applied to a larger investigation (data not provided here) into the expression patterns of host cell entry factors of SARS-CoV-2 in golden hamster organs.
Project description:Unlike other respiratory viruses, SARS-CoV-2 disproportionately causes severe disease in older adults and only rarely in children. To investigate whether differences in the upper airway immune response could contribute to this disparity, we compared nasopharyngeal gene expression in 83 children (<19-years-old; 38 with SARS-CoV-2, 11 with other respiratory viruses, 34 with no virus) and 154 adults (>40-years-old; 45 with SARS-CoV-2, 28 with other respiratory viruses, 81 with no virus). Expression of interferon-stimulated genes (ISGs) was robustly activated in both children and adults with SARS-CoV-2 compared to the respective non-viral groups, with only relatively subtle distinctions. Children, however, demonstrated markedly greater upregulation of pathways related to B cell and T cell activation and proinflammatory cytokine signaling, including TNF, IFNγ, IL-2 and IL-4 production. Cell type deconvolution confirmed greater recruitment of B cells, and to a lesser degree macrophages, to the upper airway of children. Only children exhibited a decrease in proportions of ciliated cells, the primary target for SARS-CoV-2, upon infection with the virus. These findings demonstrate that children elicit a more robust innate and adaptive immune response to SARS-CoV-2 infection in the upper airway that likely contributes to their protection from severe disease in the lower airway.
Project description:The emergence of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) variants and “anatomical escape” characteristics threaten the effectiveness of current coronavirus disease (COVID-19) vaccines. There is an urgent need to understand the immunological mechanism of broad-spectrum respiratory tract protection to guide broader vaccines development. In this study, we investigated immune responses induced by an NS1-deleted influenza virus vectored intranasal COVID-19 vaccine (dNS1-RBD) which provides broad-spectrum protection against SARS-CoV-2 variants. Intranasal delivery of dNS1-RBD induced innate immunity, trained immunity and tissue-resident memory T cells covering the upper and lower respiratory tract. It restrained the inflammatory response by suppressing early phase viral load post SARS-CoV-2 challenge and attenuating pro-inflammatory cytokine (IL-6, IL-1B, and IFN-γ) levels, thereby reducing excess immune-induced tissue injury compared with the control group. By inducing local cellular immunity and trained immunity, intranasal delivery of NS1-deleted influenza virus vectored vaccine represents a broad-spectrum COVID-19 vaccine strategy to reduce disease burden. To investigate the immune response, pathological process caused by SARS-CoV-2 Beta variants infection in Golden Hamster lung. Golden hamsters were vaccinated with dNS1-RBD vaccine at day0 and day 14, and 2 months later the vccinated hamster were challenged with SARS-CoV-2 Beta varians together with control group hamster. Then the lung samples were collected at 0, 1, 3, 5 post infection to sequence for the RNA-seq data, then performed gene expression analysis using data obtained from RNA-seq.
Project description:Severe COVID-19 is characterized by overproduction of immune mediators, but the role of interferons (IFNs) of the type I (IFN-I) or type III (IFN-III) families remains debated. We scrutinized the production of IFNs along the respiratory tract of COVID-19 patients and found that high levels of IFN-III, and to a lesser extent IFN-I, characterize the upper airways of patients with high viral burden but reduced disease risk or severity. Production of specific IFN-III, but not IFN-I, members denotes patients with a mild pathology and efficiently drives the transcription of genes that protect against SARS-CoV-2. In contrast, compared to subjects with other infectious or non-infectious lung pathologies, IFNs are over-represented in the lower airways of patients with severe COVID-19 that exhibit gene pathways associated with increased apoptosis and decreased proliferation. Our data demonstrate a dynamic production of IFNs in SARS-CoV-2-infected patients, and show IFNs play opposing roles at distinct anatomical sites.
Project description:The emergence of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2) variants and “anatomical escape” characteristics threaten the effectiveness of current coronavirus disease (COVID-19) vaccines. There is an urgent need to understand the immunological mechanism of broad-spectrum respiratory tract protection to guide broader vaccines development. In this study, we investigated immune responses induced by an NS1-deleted influenza virus vectored intranasal COVID-19 vaccine (dNS1-RBD) which provides broad-spectrum protection against SARS-CoV-2 variants. Intranasal delivery of dNS1-RBD induced innate immunity, trained immunity and tissue-resident memory T cells covering the upper and lower respiratory tract. It restrained the inflammatory response by suppressing early phase viral load post SARS-CoV-2 challenge and attenuating pro-inflammatory cytokine (IL-6, IL-1B, and IFN-γ) levels, thereby reducing excess immune-induced tissue injury compared with the control group. By inducing local cellular immunity and trained immunity, intranasal delivery of NS1-deleted influenza virus vectored vaccine represents a broad-spectrum COVID-19 vaccine strategy to reduce disease burden. To investigate the immune response generated by dNS1-RBD vaccine in C57BL/6 mouse lung, we vaccinated C57BL/6 mice and collect the lung samples to sequence for the RNA-seq data, then performed gene expression analysis using data obtained from RNA-seq of 5 different time points before and after vaccinated with dNS1-RBD vaccine.