Project description:Pandemic influenza viruses modulate pro-inflammatory responses that can lead to immunopathogenesis. We present an extensive and systematic profiling of lipids, metabolites and proteins in respiratory compartments of ferrets infected with either 1918 or 2009 human pandemic H1N1 influenza viruses. Integrative analysis of high-throughput omics data with virologic and histopathologic data uncovered relationships between host responses and phenotypic outcomes of viral infection. Pro-inflammatory lipid precursors in the trachea following 1918 infection correlated with severe tracheal lesions. Using an algorithm to infer cell quantities changes from gene expression data, we found enrichment of distinct T cell subpopulations in the trachea. There was also a predicted increase in inflammatory monocytes in the lung of 1918 virus-infected animals that was sustained throughout infection. This study presents a unique resource to the influenza research community and demonstrates the utility of an integrative systems approach for characterization of lipid metabolism alterations underlying respiratory responses to viruses.
Project description:Incursions of new pathogenic viruses into humans from animal reservoirs are occurring with alarming frequency. The molecular underpinnings of immune recognition, host responses, and pathogenesis in this setting arepoorly understood. We studied pandemic influenza viruses to determine the mechanism by which increasing glycosylation during evolution of surface proteins facilitates diminished pathogenicity in adapted viruses. ER stressduring infection with poorly glycosylated pandemic strains activated the unfolded protein response, leading to inflammation, acute lung injury, and mortality. Seasonal strains or viruses engineered to mimic adapted viruses displaying excess glycans on the hemagglutinin did not cause ER stress, allowing preservation of the lungs and survival. We propose that ER stress resultingfrom recognition of non-adapted viruses is utilized to discriminate “non-self” at the level of protein-processing and to activate immune responses, with unintended consequences on pathogenesis. Understanding this mechanism should improve strategies for treating acute lung injury from zoonotic viral infections. Lung transcription analysis of Influenza A virus infected mice.
Project description:The determinants of influenza transmission remain poorly understood. Swine influenza viruses preferentially attach to receptors found in the upper airways; however, most swine influenza viruses fail to transmit efficiently from swine to humans, and from human-to-human. The pandemic 2009 H1N1 (H1N1pdm) virus was a rare exception of a swine virus that acquired efficient transmissibility from human-to-human, and is reflected in efficient respiratory droplet transmission in ferrets. We hypothesize that virus-induced host responses in the upper airways correlate with airborne transmission in ferrets. To address this question, we used the H1N1pdm virus and swine influenza A/swine/Hong Kong/201/2010 (HK201) virus that has comparable titre in the ferret nasopharynx, but it exhibits differential transmissibility in ferrets via respiratory droplet route. We performed a transcriptomic analysis of tissues from the upper and lower respiratory tract from ferrets infected with either H1N1pdm or HK201 viruses using ferret-specific Agilent oligonucleotide arrays. We found differences in the kinetics of the innate immune response elicited by these two viruses that varied across tissues.
Project description:During a pandemic, mitigation as well as protection of system-critical or vulnerable institutions requires massively parallel, yet cost-effective testing to monitor the spread of agents such as the current SARS-CoV2 virus. Here we present SARSeq, saliva analysis by RNA sequencing, as an approach to monitor presence of SARS-CoV2 and other respiratory viruses performed on tens of thousands of samples in parallel. SARSeq is based on next generation sequencing of multiple amplicons generated in parallel in a multiplexed RT-PCR reaction. It relies on a two-dimensional unique dual indexing strategy using four indices in total, for unambiguous and scalable assignment of reads to individual samples. We calibrated this method using dilutions of synthetic RNA and virions to show sensitivity down to a few molecules, and applied it to hundreds of patient samples validating robust performance across various sample types. Double blinded benchmarking to gold-standard quantitative RT-PCR performed in a clinical setting and a human diagnostics laboratory showed robust performance up to a Ct of 36. The false positive rate, likely due to cross contamination during sample pipetting, was estimated at 0.04-0.1%. In addition to SARS-CoV2, SARSeq detects Influenza A and B viruses as well as human rhinovirus and can be easily expanded to include detection of other pathogens. In sum, SARSeq is an ideal platform for differential diagnostic of respiratory diseases at a scale, as is required during a pandemic.
Project description:Respiratory viruses such as SARS-CoV-2 are pathogens that can reach pandemic proportions. The early human response to respiratory viruses are in the nasal cavity and nasopharyngeal regions. Defining biomarkers of disease trajectory at the time of a positive test is important for opting for treatment and monitoring decisions. We hypothesize that the nasopharyngeal tRNA profiles can be used to predict symptom severity resulting from SARS-CoV-2 infection. We carried out multiplex small RNA sequencing (MSR-seq) on nasopharyngeal swaps to measure the human tRNA response to SARS-CoV-2 infection. Our result simultaneously measured full-length tRNA abundance, tRNA modifications, and tRNA fragmentation among individuals that went on to develop no/mild or severe symptoms. We identified distinct tRNA signatures that can predict the clinical outcome of SARS-CoV-2 infected individual at the time of a positive test. These results highlight the utility of using host tRNA properties as biomarkers for clinical applications.
Project description:Incursions of new pathogenic viruses into humans from animal reservoirs are occurring with alarming frequency. The molecular underpinnings of immune recognition, host responses, and pathogenesis in this setting arepoorly understood. We studied pandemic influenza viruses to determine the mechanism by which increasing glycosylation during evolution of surface proteins facilitates diminished pathogenicity in adapted viruses. ER stressduring infection with poorly glycosylated pandemic strains activated the unfolded protein response, leading to inflammation, acute lung injury, and mortality. Seasonal strains or viruses engineered to mimic adapted viruses displaying excess glycans on the hemagglutinin did not cause ER stress, allowing preservation of the lungs and survival. We propose that ER stress resultingfrom recognition of non-adapted viruses is utilized to discriminate “non-self” at the level of protein-processing and to activate immune responses, with unintended consequences on pathogenesis. Understanding this mechanism should improve strategies for treating acute lung injury from zoonotic viral infections.
Project description:Single-cell RNA-sequencing was performed on the tumor microenvironment of the glioblastomas isolated from PDOX models (Golebiewska et al., Acta Neuropathologica, 2020; Oudin et al., STAR Protocols 2021). Sample names correspond to PDOX models. Normal mouse brain was used as a contol. One PDOX model was treated with temolozomide (P3TMZ).