Project description:To further understand the molecular pathogenesis of the 2009 pandemic H1N1 influenza virus infection, we profiled cellular miRNAs of lung tissue from BALB/c mice infected with influenza virus BJ501 and a mouse-adapted influenza virus A/Puerto Rico/8/34 (H1N1)(PR8) as a comparison.
Project description:While pandemic 2009 H1N1 influenza A viruses were responsible for numerous severe infections in humans, these viruses do not typically cause corresponding severe disease in mammalian models. However, the generation of a virulent 2009 H1N1 virus following serial lung passage in mice has allowed for the modeling of human lung pathology in this species. Genetic determinants of mouse-adapted 2009 H1N1 viral pathogenicity have been identified, but the molecular and signaling characteristics of the host response following infection with this adapted virus have not been described. Here, we compared the gene-expression response following infection of mice with A/CA/04/2009 (CA/04) or the virulent mouse-adapted strain (MA-CA/04). Microarray analysis revealed that increased pathogenicity of MA-CA/04 was associated with: (1) early and sustained inflammatory and interferon response that could be driven in part by interferon regulatory factors (IRFs) and increased NF-kappaB activation, as well as inhibition of the negative regulator TRIM24, (2) early and persistent infiltration of immune cells, including inflammatory macrophages, and (3) the absence of activation of lipid metabolism later in infection, that may be mediated by nuclear receptors inhibition, including PPARG, HNF1A and 4A, with pro-inflammatory consequences. Further investigation of these signatures in the host response to other H1N1 viruses of varied pathogenicity confirmed their general relevance for virulence of influenza virus and suggested that lung response to MA-CA/04 virus was similar to that following lethal H1N1 r1918 influenza virus. This study links for the first time differential activation of IRFs, nuclear receptors, and macrophage infiltration with influenza virulence in vivo.
Project description:This study used virological, histological, immunological and global gene expression to compare the virlence of two newly emerged 2009 H1N1 isolates (A/Mexico/InDRE4487/2009 and A/Mexico/4108/2009) and current seasonal H1N1 influenza strain (A/Kawasaki/UTK-4/2009) in experimentally infected cynomolgus macaques. We showed that infection of macaques with two genetically similar but clinically distinct SOIV isolates from the early stage of the pandemic (A/Mexico/4108/2009 and A/Mexico/InDRE4487/2009) resulted in upper and lower respiratory tract infections and clinical disease ranging from mild to severe pneumonia. Disease associated with these SOIV isolates was clearly advanced over the mild infection caused by A/Kawasaki/UTK-4/2009, a current seasonal strain.
Project description:Early life environmental exposure, particularly during perinatal period, can have a lifelong impact on organismal development and physiology. The biological rationale for this phenomenon is to promote physiological adaptation to the anticipated environment based on early life experience. However, perinatal exposure to adverse environments can also be associated with adult-onset disorders. Multiple environmental stressors induce glucocorticoids, which prompted us to investigate their role in developmental programming. Here, we report that perinatal glucocorticoid exposure had long-term consequences and resulted in diminished CD8 T cell response in adulthood and impaired control of tumor growth and bacterial infection. We found that perinatal glucocorticoid exposure resulted in persistent alteration of the hypothalamic-pituitaryadrenal (HPA) axis. Consequently, the level of the hormone in adults was significantly reduced, resulting in decreased CD8 T cell function. Our study thus demonstrates that perinatal stress can have long-term consequences on CD8 T cell immunity by altering HPA axis activity.
Project description:Differential expression was determined in Calu-3 cells between mock infected and infected with H1N1 influenza virus A/Netherlands/602/2009 at nine time points post-infection. As a comparison, cells were also infected with A/CA/04/2009 H1N1 influenza virus at 4 time points post-infection.
Project description:Sperm contributes genetic and epigenetic information to the embryo to efficiently support development. However, the mechanism underlying such developmental competence remains elusive. Here, we investigated whether all sperm cells have a common epigenetic configuration that primes transcriptional program for embryonic development. We show for the first time that remodelling of histones during spermiogenesis results in the retention of methylated histone H3 at the same genomic location in every sperm cell. This homogeneously methylated fraction of histone H3 in the sperm genome is maintained during early embryonic replication. Such methylated histone fraction resisting postfertilisation reprogramming marks developmental genes whose expression is perturbed upon experimental reduction of histone methylation. A similar homogeneously methylated histone H3 fraction is detected in human sperm. Altogether, we uncover a conserved mechanism of paternal epigenetic information transmission to the embryo through the homogeneous retention of methylated histone in a sperm cells population.
Project description:To find the different host response during H5N1 and H1N1 infection, we have employed whole genome microarray expression profiling as a discovery platform to identify genes differentially expressed in mouse lungs infected by H5N1 and H1N1 virus. BALB/c mice were infected with live H5N1 virus , live H1N1 virus, or inactivated H5N1 virus or allantoic fluid (AF) for 24 h.
Project description:To determine whether differential expression of cellular microRNAs plays a role in the host response to Influenza A (H1N1) infection, we have employed the Agilent miRNA microarray (V3) as a discovery platform to identify microRNAs between the critically ill Patients with Influenza A (H1N1) and the healthy controls.
Project description:While pandemic 2009 H1N1 influenza A viruses were responsible for numerous severe infections in humans, these viruses do not typically cause corresponding severe disease in mammalian models. However, the generation of a virulent 2009 H1N1 virus following serial lung passage in mice has allowed for the modeling of human lung pathology in this species. Genetic determinants of mouse-adapted 2009 H1N1 viral pathogenicity have been identified, but the molecular and signaling characteristics of the host response following infection with this adapted virus have not been described. Here, we compared the gene-expression response following infection of mice with A/CA/04/2009 (CA/04) or the virulent mouse-adapted strain (MA-CA/04). Microarray analysis revealed that increased pathogenicity of MA-CA/04 was associated with: (1) early and sustained inflammatory and interferon response that could be driven in part by interferon regulatory factors (IRFs) and increased NFM-oM-^AM-+B activation, as well as inhibition of the negative regulator TRIM24, (2) early and persistent infiltration of immune cells, including inflammatory macrophages, and (3) the absence of activation of lipid metabolism later in infection, that may be mediated by nuclear receptors inhibition, including PPARG, HNF1A and 4A, with pro-inflammatory consequences. Further investigation of these signatures in the host response to other H1N1 viruses of varied pathogenicity confirmed their general relevance for virulence of influenza virus and suggested that lung response to MA-CA/04 virus was similar to that following lethal H1N1 r1918 influenza virus. This study links for the first time differential activation of IRFs, nuclear receptors, and macrophage infiltration with influenza virulence in vivo. Six-to-eight-week-old female BALB/c mice were anesthetized and inoculated with 50 M-NM-<l of phosphate-buffered saline (PBS; Mock) or with 10^6 pfu of virus in a 50 M-NM-<l volume. Nine animals per condition group were used for tarray analysis, two or three animals per time point. There were seven condition groups: A/California/04/2009, MA1-A/California/04/2009, A/Mexico/4482/09, A/Brisbane/59/07, A/New Jersey/8/76, the reconstructed 1918 virus and timeM-bM-^@M-^Smatched mocks.