Project description:This series includes 1 microarray used to detect a human metapneumovirus strain associated with critical respiratory illness in an elderly male with leukemia (Chiu, et al 2006) Keywords: viral detection
Project description:Human metapneumovirus (HMPV) is a primary causative agent of acute lower respiratory tract infections. We used single cell RNA-sequencing (scRNA-seq) to assess lung immune profiles in a mouse model of HMPV infection.
Project description:Human metapneumovirus (HMPV) is a primary causative agent of acute upper respiratory tract infections. We used single cell RNA-sequencing (scRNA-seq) to assess nasal immune profiles in a mouse model of HMPV infection.
Project description:Background. Human Metapneumovirus (HMPV) and Respiratory Syncytial Virus (RSV), are responsible for respiratory diseases mostly in children. In spite of the resemblance between these two pneumoviruses, they elicit a different extent of immune response. miRNAs are small non coding RNAs that regulate gene expression and are involved in numerous cellular processes including the immune system. Methodology. Human monocyte-derived dendritic cells (moDC) were differentiated from peripheral blood mononuclear cells and infected at an MOI of 3 for 24h. RNA was isolated to analyze the miRNAs transcription by high throughput sequencing using illumina technology. Principal findings. Infection with HMPV up-regulated the expression of hsa-miR-4448, while RSV infection induced significant expression of hsa-miR-30a-5p, hsa-miR-182-5p, hsa-miR-1913, hsa37, miR-4448 and hsa-miR-4634. Conclusions/Significance. In human monocyte derived dendritic cells (moDC), RSV and HMPV induced different profiles of miRNA expression. Understanding the changes of miRNA expression profiles by RSV and HMPV in immune cells will further our understanding of the differential immune response induced by these respiratory viruses
Project description:In vitro infection experiment with genetically modified human metapneumovirus (HMPV) to study the function of the viral small hydrophobic (SH) protein.
Project description:Internal N6-methyladenosine (m6A) modification of RNA is one of the most common and abundant modifications in eukaryotic cells as well as in viruses. However, the biological role(s) of RNA m6A in virus-host interaction remains elusive. Using human metapneumovirus (hMPV), a medically important non-segmented negative-sense RNA virus as a model, we demonstrate that m6A serves as a molecular marker for innate immune discrimination self and nonself RNAs. We show that hMPV RNAs are m6A methylated and that viral m6A methylation promotes hMPV replication and gene expression. HMPV infection leads to differential expression of interferon-related genes involved in innate immune signaling pathways. Inactivating these m6A sites with synonymous mutations resulted in m6A deficient recombinant hMPVs that induced significantly higher expression of type I interferon that restricted viral replication. Notably, the induction of type I interferons by m6A-deficient rhMPVs and virion RNA was dependent on the cytoplasmic RNA sensor RIG-I, not MDA5. Mechanistically, m6A-deficient virion RNA induces higher expression of RIG-I, enhances its binding affinity to RIG-I, and facilitates the conformational change of RIG-I, leading to enhanced induction of type I IFN expression. The replication of m6A-deficient rhMPVs was attenuated in wild type A459 cells but was restored in cells knocked out for RIG-I and MAVS. Furthermore, m6A-deficient rhMPVs triggered higher type I interferon in vivo and were significantly attenuated in the lower respiratory tract yet retained high immunogenicity in cotton rats. Collectively, our results highlight that (i) virus acquires m6A in their RNAs as a means of mimicking cellular RNA to avoid the detection by innate immunity; and (ii) viral m6A RNA can serve as a novel target to attenuate hMPV for vaccine purposes.
Project description:Respiratory viruses pose an ongoing threat to human health, with excessive cytokine secretion playing a critical role in severe illness and mortality. However, the complex relationship between cytokine secretion and viral infection remains poorly understood. Here, we have unraveled the role of cxcl8 as an early response gene to respiratory EV-D68 infection. The upregulation of CXCL8 by viral infection is found to be crucial for EV-D68 replication. Importantly, silencing CXCL8 or its receptors, CXCR1/2, significantly impedes EV-D68 replication. Upon recognition of CXCL8 by CXCR1/2, the MAPK pathway is activated, facilitating the translocation of the essential host cofactor hnRNP K from the nucleus to the cytoplasm. This translocation enhances the recognition of viral RNA by hnRNP K in the cytoplasm, promoting the functionality of the 5’UTR region in the viral genome. Interestingly, the VP4 structural protein of EV-D68 contains a mimic motif of human immunoreceptor tyrosine-based activation motif (ITAM) that interacts with syk and triggers the PI3K/AKT signaling pathway, resulting in elevated CXCL8 gene expression for viral replication. Moreover, our investigations reveal the conservation and significance of the CXCL8 signaling pathway across various prominent human respiratory viruses, including SARS-CoV-2, influenza, and rhinovirus. In summary, our findings unveil a paradigmatic mechanism through which respiratory viruses exploit cytokine-mediated intercellular communication to transmit signals that optimize viral replication. This deepens our understanding of the shared evolutionary strategies employed by respiratory viruses and opens up new avenues for the development of broad-spectrum antiviral drugs targeting respiratory pathogens.