Project description:The mechanisms by which pulmonary lesions and fibrosis are generated during SARS-CoV infection are not known. Using high-throughput mRNA profiling, we examined the transcriptional response of wild-type (WT), type I interferon receptor knockout (IFNAR1−/−), and STAT1 knockout (STAT1−/−) mice infected with a recombinant mouse-adapted SARS-CoV (rMA15) to better understand the contribution of specific gene expression changes to disease progression.
Project description:The mechanisms by which pulmonary lesions and fibrosis are generated during SARS-CoV infection are not known. Using high-throughput mRNA profiling, we examined the transcriptional response of wild-type (WT), type I interferon receptor knockout (IFNAR1−/−), and STAT1 knockout (STAT1−/−) mice infected with a recombinant mouse-adapted SARS-CoV (rMA15) to better understand the contribution of specific gene expression changes to disease progression. Ten week old 129S6/SvEv wild-type, STAT1−/− (Taconic Farms, Germantown, NY), and IFNAR1−/− mice bred on a 129SvEv background were anesthetized with a ketamine and infected intranasally with either phosphate-buffered saline (PBS) alone (Invitrogen, Carlsbad, CA) or 1 × 10^5 PFU rMA15-PBS. Mice were euthanized and left lungs were harvested from individual mice (a total of 3 infected mice from each strain) at days 2, 5, and 9 postinfection (dpi) for microarray analyses. Lung samples were taken from mock-infected animals from each of the strains at 5 dpi.
Project description:Host and genetic viral adaptations enable development of an immunocompetent mouse model of Zika virus infection. This study explored the effect of wildtype Zika virus (ZIKV) and mouse adapted ZIKV infection on the transcriptional profile of mouse adult neuronal stem cells.
Project description:To dissect the nature of the immune dysregulation induced by SARS-CoV-2 infection in mouse lungs using mouse-adapted strains of the virus. Comparisons were performed using bulk RNA-seq data from mouse (C57BL/6) lung homogenates taken 3 days post-infection with mouse-adapted SARS-CoV-2, both early and late (virulent) passages, or mock-infected mice.
Project description:We previously reported widespread differential expression of long non-protein-coding RNAs (ncRNAs) in response to virus infection. Here, we expanded the study through small RNA transcriptome sequencing analysis of the host response to both severe acute respiratory syndrome coronavirus (SARS-CoV) and influenza virus infections across four founder mouse strains of the Collaborative Cross, a recombinant inbred mouse resource for mapping complex traits. We observed differential expression of over 200 small RNAs of diverse classes during infection. A majority of identified microRNAs (miRNAs) showed divergent changes in expression across mouse strains with respect to SARS-CoV and influenza virus infections and responded differently to a highly pathogenic reconstructed 1918 virus compared to a minimally pathogenic seasonal influenza virus isolate. Novel insights into miRNA expression changes, including the association with pathogenic outcomes and large differences between in vivo and in vitro experimental systems, were further elucidated by a survey of selected miRNAs across diverse virus infections. The small RNAs identified also included many non-miRNA small RNAs, such as small nucleolar RNAs (snoRNAs), in addition to nonannotated small RNAs. An integrative sequencing analysis of both small RNAs and long transcripts from the same samples showed that the results revealing differential expression of miRNAs during infection were largely due to transcriptional regulation and that the predicted miRNA-mRNA network could modulate global host responses to virus infection in a combinatorial fashion. These findings represent the first integrated sequencing analysis of the response of host small RNAs to virus infection and show that small RNAs are an integrated component of complex networks involved in regulating the host response to infection. IMPORTANCE: Most studies examining the host transcriptional response to infection focus only on protein-coding genes. However, mammalian genomes transcribe many short and long non-protein-coding RNAs (ncRNAs). With the advent of deepsequencing technologies, systematic transcriptome analysis of the host response, including analysis of ncRNAs of different sizes, is now possible. Using this approach, we recently discovered widespread differential expression of host long (>200 nucleotide[nt]) ncRNAs in response to virus infection. Here, the samples described in the previous report were again used, but we sequenced another fraction of the transcriptome to study very short (about 20 to 30 nt) ncRNAs. We demonstrated that virus infection also altered expression of many short ncRNAs of diverse classes. Putting the results of the two studies together, we show that small RNAs may also play an important role in regulating the host response to virus infection. The small RNA transcriptome deep sequencing analysis was performed on lung samples from our previously published study (Unique signatures of long noncoding RNA expression in response to virus infection and altered innate immune signaling , X Peng, MBio. 2010 Oct 26;1(5). pii: e00206-10.). We infected four of the eight founder mouse strains used in generating the Collaborative Cross, a recombinant inbred mouse resource for mapping complex traits (41). These strains included 129S1/SvImJ (129/S1), WSB/EiJ (WSB), PWK/PhJ (PWK), and CAST/EiJ (CAST) mice. Ten-week-old mice were intranasally infected with phosphate-buffered saline (PBS) alone or with 1X10^5 PFU of mouse adapted severe acute respiratory syndrome coronavirus (SARS-CoV; rMA15), or 500 PFU of influenza A virus strain A/Pr/8/34 (H1N1; PR8). To match the previous whole-transcriptome analysis, we performed small RNA transcriptome sequencing analysis on the same eight samples from mice with SARS-CoV infections, including one SARS-CoV rMA15-infected mouse and one matched mock-infected mouse from each of the four strains at 2 days postinfection (dpi). In addition, we sequenced the small RNA transcriptome for 12 samples obtained from influenza virus infected mice, including two PR8-infected mice and one matched mockinfected mouse from each of the four strains at 2 dpi.
Project description:Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions of individuals worldwide, causing a severe global pandemic. Mice models are wildly used to investigate viral infection pathology, antiviral drugs, and vaccine development. However, since wild-type mice do not express human angiotensin-converting enzyme 2 (hACE2), which mediates SARS-CoV-2 entry into human cells, they are not susceptible to infection with SARS-CoV-2 and are not suitable to simulate symptomatic COVID-19 disease. HACE2 transgenic mice could provide an efficient model, but they are expensive, not always readily available and practically restricted to specific strain(s). Since additional models are needed to study the disease at varying genetic and immune backgrounds, there is a dearth of mouse models for SARS-CoV-2 infection. Here we report the application of lentiviral vectors to generate hACE2 expression in mouse lung epithelial cells (LET1) as well as in interferon receptor knock-out (IFNAR1-/-) mice. Lenti-hACE2 transduction supported SARS-CoV-2 replication both in vitro and in vivo, simulating mild acute lung disease1. Gene expression analysis revealed two modes of immune responses to SARS-CoV-2 infection: one in response to the exposure of mouse lungs to SARS-CoV-2 particles in the absence of productive viral replication, and the second in response to a productive infection. This approach expands our knowledge on the role of type-1 interferon signaling in COVID-19 disease, and can be further implemented for a range of COVID-19 studies and drug development.
Project description:Using a mouse-adapted SARS-CoV-2 variant (SARS-CoV-2 MA), we found that endogenous type I and type III IFNs synergize to limit SARS-CoV-2 replication and to expedite virus clearance and that enhanced disease progression in aged mice depends on impaired type II IFN immunity
Project description:Using a mouse-adapted SARS-CoV-2 variant (SARS-CoV-2 MA20), newly generated in our lab, we found that endogenous type I and type III IFNs synergize to limit SARS-CoV-2 replication and to expedite virus clearance and that enhanced disease progression in aged mice depends on impaired type II IFN immunity
Project description:Type I Interferons (IFNs) are potent inhibitors of viral replication. Here, we reformatted the natural murine and human type I Interferon-α/β receptors IFNAR1 and IFNAR2 into fully synthetic biological switches. The transmembrane and intracellular domains of natural IFNAR1 and IFNAR2 were conserved, whereas the extracellular domains were exchanged by nanobodies directed against the fluorescent proteins Green fluorescent protein (GFP) and mCherry. Using this approach, multimeric single-binding GFP-mCherry ligands induced synthetic IFNAR1/IFNAR2 receptor complexes and initiated STAT1/2 mediated signal transduction via Jak1 and Tyk2. Homodimeric GFP and mCherry ligands showed that IFNAR2 but not IFNAR1 homodimers were sufficient to induce sustained STAT1/2 signaling. Transcriptome analysis revealed that synthetic murine type I IFN signaling was highly comparable to IFNα4 signaling and resulted in efficient elimination of vesicular stomatitis virus (VSV) in a cell culture based viral infection model using MC57 cells stimulated with synthetic type IFN ligands. Using intracellular deletion variants and point mutations, Y510 and Y335 in murine IFNAR2 were verified as unique phosphorylation sites for STAT1/2 activation, whereas the other tyrosine residues in IFNAR1 and IFNAR2 were not involved in STAT1/2 phosphorylation. Comparative analysis of synthetic human IFNARs supporting this finding. In summary, our data showed that synthetic type I IFN signal transduction is originating from IFNAR2 rather than IFNAR1.