The global spread of SARS-CoV-2 led to major economic and health challenges worldwide. Revealing host genes essential for infection by multiple variants of SARS-CoV-2 can provide insights into the virus pathogenesis, and facilitate the development of novel therapeutics. Here, employing a genome-scale CRISPR screen, we provide a comprehensive data-set of cellular factors that are exploited by wild type SARS-CoV-2 as well as two additional recently emerged variants of concerns (VOCs), Alpha and Beta.
View Article and Find Full Text PDFHLA transgenic mice are instrumental for evaluation of human-specific immune responses to viral infection. Mice do not develop COVID-19 upon infection with SARS-CoV-2 due to the strict tropism of the virus to the human ACE2 receptor. The aim of the current study was the implementation of an adenovirus-mediated infection protocol for human ACE2 expression in HLA transgenic mice.
View Article and Find Full Text PDFThe COVID-19 pandemic led to development of mRNA vaccines, which became a leading anti-SARS-CoV-2 immunization platform. Preclinical studies are limited to infection-prone animals such as hamsters and monkeys in which protective efficacy of vaccines cannot be fully appreciated. We recently reported a SARS-CoV-2 human Fc-conjugated receptor-binding domain (RBD-hFc) mRNA vaccine delivered via lipid nanoparticles (LNPs).
View Article and Find Full Text PDFis a highly infectious intracellular bacterium representing the causative agent of tularemia, a severe disease which requires prompt antibacterial intervention for mitigating its potential high mortality. Inhaled bacteria interact with lung cells belonging to various subpopulations, including those of the epithelium. As of today, the host epithelial response to inhalational infection with is poorly understood.
View Article and Find Full Text PDFThe novel highly transmissible human coronavirus SARS-CoV-2 is the causative agent of the COVID-19 pandemic. Thus far, there is no approved therapeutic drug specifically targeting this emerging virus. Here we report the isolation and characterization of a panel of human neutralizing monoclonal antibodies targeting the SARS-CoV-2 receptor binding domain (RBD).
View Article and Find Full Text PDFDiagnostic identification of pathogens is usually accomplished by isolation of the pathogen or its substances, and should correlate with the time and site of infection. Alternatively, immunoassays such as enzyme-linked immunosorbent assay (ELISA) tests for quantification of serum antibodies are expedient and are usually employed for retrospective diagnostic of a particular infective agent. Here, the potential of cell-based immunoassays for early pathogen detection was evaluated by quantification of specific, antigen-activated, low-frequency IFNγ-secreting cells in mouse spleens following infection with various pathogens.
View Article and Find Full Text PDFAnthrax is a lethal disease caused by the Gram-positive spore-producing bacterium . We previously demonstrated that disruption of gene, encoding the chaperone/protease HtrA (High Temperature Requirement A of ) results in significant virulence attenuation, despite unaffected ability of Δ strains (in which the gene was deleted) to synthesize the key anthrax virulence factors: the exotoxins and capsule. Δ strains exhibited increased sensitivity to stress regimens as well as silencing of the secreted starvation-associated Neutral Protease A (NprA) and down-modulation of the bacterial S-layer.
View Article and Find Full Text PDFFrancisella tularensis is the intracellular bacterial pathogen causing the respiratory life-threatening disease tularemia. Development of tularemia vaccines has been hampered by an incomplete understanding of the correlates of immunity. Moreover, the importance of lung cellular immunity in vaccine-mediated protection against tularemia is a controversial matter.
View Article and Find Full Text PDFHost shutoff is a common strategy used by viruses to repress cellular mRNA translation and concomitantly allow the efficient translation of viral mRNAs. Here we use RNA-sequencing and ribosome profiling to explore the mechanisms that are being utilized by the Influenza A virus (IAV) to induce host shutoff. We show that viral transcripts are not preferentially translated and instead the decline in cellular protein synthesis is mediated by viral takeover on the mRNA pool.
View Article and Find Full Text PDFThe signal recognition particle (SRP) receptor is a major player in the pathway of membrane protein biogenesis in all organisms. The receptor functions as a membrane-bound entity but very little is known about its targeting to the membrane. Here, we demonstrate in vivo that the Escherichia coli SRP receptor targets the membrane co-translationally.
View Article and Find Full Text PDFTraumatic brain injury (TBI) is a major cause of death and disability worldwide. It causes progressive tissue atrophy and consequent neurological dysfunctions. TBI is accompanied by neuroinflammation, a process mediated largely by microglia.
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