Viruses utilize a number of host factors in order to carry out their replication cycles. Influenza A virus (IAV) and human respiratory syncytial virus (RSV) both infect the tissues of the respiratory tract, and as such we hypothesize that they might require similar host factors. Several published genome-wide screens have identified putative IAV host factors; however, there is significant discordance between their hits.
View Article and Find Full Text PDFViral pneumonia has been frequently reported during early stages of influenza virus pandemics and in many human cases of highly pathogenic avian influenza (HPAI) H5N1 virus infection. To better understand the pathogenesis of this disease, we produced nonlethal viral pneumonia in rhesus macaques by using an HPAI H5N1 virus (A/Anhui/2/2005; referred to as Anhui/2). Infected macaques were monitored for 14 days, and tissue samples were collected at 6 time points for virologic, histopathologic, and transcriptomic analyses.
View Article and Find Full Text PDFUnderstanding the role of host factors during lethal influenza virus infection is critical to deciphering the events that determine the fate of the host. One such factor is encoded by the Mx1 gene, which confers resistance to influenza virus infection. Here, we compared pathology and global gene expression profiles in lung tissue from BALB/c (Mx1(-)) and BALB · A2G-Mx1 mice (Mx1(+/+)) infected with the fully reconstructed 1918 pandemic influenza virus.
View Article and Find Full Text PDFInnate immune deficiencies result in a spectrum of severe clinical outcomes following infection. In particular, there is a strong association between loss of the signal transducer and activator of transcription (Stat) pathway, breach of the blood-brain barrier (BBB), and virus-induced neuropathology. The gene signatures that characterize resistance, disease, and mortality in the virus-infected nervous system have not been defined.
View Article and Find Full Text PDFEbola virus is the etiologic agent of a lethal hemorrhagic fever in humans and nonhuman primates with mortality rates of up to 90%. Previous studies with Zaire Ebola virus (ZEBOV), mouse-adapted virus (MA-ZEBOV), and mutant viruses (ZEBOV-NP(ma), ZEBOV-VP24(ma), and ZEBOV-NP/VP24(ma)) allowed us to identify the mutations in viral protein 24 (VP24) and nucleoprotein (NP) responsible for acquisition of high virulence in mice. To elucidate specific molecular signatures associated with lethality, we compared global gene expression profiles in spleen samples from mice infected with these viruses and performed an extensive functional analysis.
View Article and Find Full Text PDFPeriodic outbreaks of highly pathogenic avian H5N1 influenza viruses and the current H1N1 pandemic highlight the need for a more detailed understanding of influenza virus pathogenesis. To investigate the host transcriptional response induced by pathogenic influenza viruses, we used a functional-genomics approach to compare gene expression profiles in lungs from 129S6/SvEv mice infected with either the fully reconstructed H1N1 1918 pandemic virus (1918) or the highly pathogenic avian H5N1 virus Vietnam/1203/04 (VN/1203). Although the viruses reached similar titers in the lung and caused lethal infections, the mean time of death was 6 days for VN/1203-infected animals and 9 days for mice infected with the 1918 virus.
View Article and Find Full Text PDFThe innate immune response provides the first line of defense against foreign pathogens by responding to molecules that are a signature of a pathogenic infection. Certain RNA viruses, such as influenza virus, produce double-stranded RNA as an intermediate during the replication life cycle, which activates pathogen recognition receptors capable of inducing interferon production. By engaging interferon receptors, interferon activates the JAK-STAT pathway and results in the positive feedback of interferon production, amplifying the response to viral infection.
View Article and Find Full Text PDFThe enormous toll on human life during the 1918-1919 Spanish influenza pandemic is a constant reminder of the potential lethality of influenza viruses. With the declaration by the World Health Organization of a new H1N1 influenza virus pandemic, and with continued human cases of highly pathogenic H5N1 avian influenza virus infection, a better understanding of the host response to highly pathogenic influenza viruses is essential. To this end, we compared pathology and global gene expression profiles in bronchial tissue from macaques infected with either the reconstructed 1918 pandemic virus or the highly pathogenic avian H5N1 virus A/Vietnam/1203/04.
View Article and Find Full Text PDFHumans and mice lacking the interferon signaling molecule Stat1 are sensitive to a variety of pathogens due to their presumed inability to mount a strong innate immune response. The herpes simplex virus type 1 (HSV-1) virion host shutoff (vhs) protein is a multifunctional immunomodulator that counteracts the innate immune response and viruses lacking vhs are attenuated and effective live vaccines in animal models. To investigate the interplay of viruses with an immunocompromised host, we performed functional genomics analyses on control and Stat1(-/-) mouse corneas infected with wild-type or vhs-null viruses.
View Article and Find Full Text PDFThe varicella-zoster virus (VZV) ORF9 protein is a member of the herpesvirus UL49 gene family but shares limited identity and similarity with the UL49 prototype, herpes simplex virus type 1 VP22. ORF9 mRNA is the most abundantly expressed message during VZV infection; however, little is known concerning the functions of the ORF9 protein. We have found that the VZV major transactivator IE62 and the ORF9 protein can be coprecipitated from infected cells.
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