Antiviral Gene Regulation Research Articles

Resting parasympathetic nervous system activity is associated with greater antiviral gene expression

Parasympathetic nervous system activity can downregulate inflammation, but it remains unclear how parasympathetic nervous system activity relates to antiviral activity. The present study examined associations between parasympathetic nervous system activity and cellular antiviral gene regulation in 90 adolescents (Mage = 16.28, SD = 0.73; 51.1% female) who provided blood samples and measures of cardiac respiratory sinus arrhythmia (RSA), twice, five weeks apart. Using a multilevel analytic framework, we found that higher RSA (an indicator of higher parasympathetic nervous system activity)—both at rest and during paced breathing—was associated with higher expression of Type I interferon (IFN) response genes in circulating leukocytes, even after adjusting for demographic and biological covariates. RSA was not associated with a parallel measure of inflammatory gene expression. These results identify a previously unrecognized immunoregulatory aspect of autonomic nervous system function and highlight a potential biological pathway by which parasympathetic nervous system activity may relate to health.

Microalgal extracts induce larval programming and modify growth and the immune response to bioactive treatments and LCDV in Senegalese sole post-larvae

Immunostimulants are key molecules in aquaculture since they heighten defensive responses and protection against pathogens. The present study investigated the treatment of Senegalese sole larvae with a whole-cell crude extract of the microalgae Nannochloropsis gaditana (Nanno) and programming of growth and the immune system. Larvae at hatch were treated with the Nanno extracts for 2 h and thereafter were cultivated for 32 days post-hatch (dph) in parallel with an untreated control group (CN). Dry weight and length at 21 days post-hatch (dph) were higher in post-larvae of the Nanno than CN group. These differences in weight were later confirmed at 32 dph. To evaluate changes in the immune response associated with Nanno-programming treatments, the Nanno and CN post-larvae were supplied with two bioactive compounds yeast β-glucan (Y) and a microalga extract from the diatom Phaeodactylum tricornutum (MAe). The bioactive treatments were administrated to the treatment groups through the live prey (artemia metanauplii, 200 artemia mL−1) enriched for 30 min with MAe or Y (at 2 mg mL−1 SW) or untreated prey in the case of the negative control (SW). The effect of the treatments was assessed by monitoring gene expression, enzyme activity and mortality over 48 h. The post-larvae sole supplied with the bioactive compounds Y and MAe had increased mortality at 48 h compared to the SW group. Moreover, mortality was higher in Nanno-programmed than CN post-larvae. Lysozyme and total anti-protease enzymatic activities at 6 and 24 h after the start of the trial were significantly higher in the Nanno and MAe supplied post-larvae compared to their corresponding control (CN and SW, respectively). Immune gene transcripts revealed that il1b, cxc10 and mx mRNAs were significantly different between Nanno and CN post-larvae at 6 and 24 h. Moreover, the expression of il1b, tnfa, cxc10, irf3, irf7 and mx was modified by bioactive treatments but with temporal differences. At 48 h after bioactive treatments, Y and SW post-larvae were challenged with the lymphocystis disease virus (LCDV). No difference existed in viral copy number between programming or bioactive treatment groups at 3, 6 and 24 h after LCDV challenge although the total number of copies reduced with time. Gene expression profiles in the LCDV-challenged group indicated that post-larvae triggered a wide defensive response compared to SWC 24 h after challenge, which was modulated by programming and bioactive compound treatments. Cluster analysis of expressed genes separated the SW and Y groups indicating long-lasting effects of yeast β-glucan treatment in larvae. A noteworthy interaction between Nanno-programming and Y-treatment on the regulation of antiviral genes was observed. Overall, the data demonstrate the capacity of microalgal crude extracts to modify sole larval plasticity with long-term effects on larval growth and the immune responses.

Population-based RNA profiling in Add Health finds social disparities in inflammatory and antiviral gene regulation to emerge by young adulthood

Health in later life varies significantly by individual demographic characteristics such as age, sex, and race/ethnicity, as well as by social factors including socioeconomic status and geographic region. This study examined whether sociodemographic variations in the immune and inflammatory molecular underpinnings of chronic disease might emerge decades earlier in young adulthood. Using data from 1,069 young adults from the National Longitudinal Study of Adolescent to Adult Health (Add Health)-the largest nationally representative and ethnically diverse sample with peripheral blood transcriptome profiles-we analyzed variation in the expression of genes involved in inflammation and type I interferon (IFN) response as a function of individual demographic factors, sociodemographic conditions, and biobehavioral factors (smoking, drinking, and body mass index). Differential gene expression was most pronounced by sex, race/ethnicity, and body mass index (BMI), but transcriptome correlates were identified for every demographic dimension analyzed. Inflammation-related gene expression showed the most pronounced variation as a function of biobehavioral factors (BMI and smoking) whereas type I IFN-related transcripts varied most strongly as a function of individual demographic characteristics (sex and race/ethnicity). Bioinformatic analyses of transcription factor and immune-cell activation based on transcriptome-wide empirical differences identified additional effects of family poverty and geographic region. These results identify pervasive sociodemographic differences in immune-cell gene regulation that emerge by young adulthood and may help explain social disparities in the development of chronic illness and premature mortality at older ages.

Novel Insights into Antiviral Gene Regulation of Red Swamp Crayfish, Procambarus clarkii, Infected with White Spot Syndrome Virus.

White spot syndrome virus (WSSV), one of the major pathogens of Procambarus clarkii, has caused severe disruption to the aquaculture industry of P. clarkii in China. To reveal the gene regulatory mechanisms underlying WSSV infection, a comparative transcriptome analysis was performed among WSSV-infected susceptible individuals (GS), viral resistant individuals (GR), and a non-infected control group (GC). A total of 61,349 unigenes were assembled from nine libraries. Subsequently, 515 and 1033 unigenes exhibited significant differential expression in sensitive and resistant crayfish individuals compared to the control group (GC). Many differentially expressed genes (e.g., C-type lectin 4, Peroxinectin, Prophenoloxidase, and Serine/threonine-protein kinase) observed in GR and GS play critical roles in pathogen recognition and viral defense reactions after WSSV infection. Importantly, the glycosaminoglycan biosynthesis-chondroitin sulfate/dermatan sulfate pathway was identified to play critical roles in defense to WSSV infection for resistant crayfish individuals by upregulating the chondroitin sulfate related genes for the synthesis of WSSV-sensitive, functional chondroitin sulfate chains containing E units. Numerous genes and the key pathways identified between resistant and susceptible P. clarkii individuals provide valuable insights regarding antiviral response mechanisms of decapoda species and may help to improve the selective breeding of P. clarkii WSSV-resistance.

S129 Inflammatory Cytokines Influence Respiratory Epithelial Anti-viral Immune Responses Via Inducible Epigenetic Control Of Rig1 Expression: A Model Of Early Life Origins Of Asthma?

The development of asthma is linked to early life environmental exposures and the occurrence of severe viral infections. Rapid maturation of adaptive immunity from a tolerant (Th2) to an anti-infective (Th1) state occurs in the neonatal period. We hypothesised that the airway inflammatory milieu, driven by the maturing immune response to environmental exposures may have important effects on the development of anti-viral innate immunity at the level of the epithelium. We studied whether the inflammatory environment of the airway epithelium modulates gene expression via epigenetic regulation of anti-viral genes as a model of the development of a long term abnormality which is a hallmark of asthma. We optimised an in-vitro model using AALEB, human immortalised bronchial epithelial-derived cells which were pre-treated for 24 h with cytokines that mimic Th1 environment (IFNy, 10 ng/ml) and Th2 (IL-13, 10 ng/ml) before being infected with RSV A, MOI=2 for 48 h. Quantitative real-time PCR with Taqman primers was used to assess expression of innate genes. Cells were collected after 48 h and stored in Trizol. Chromatin Immuno Precipitation (ChIP) with antibodies against histone modifications was used to assess epigenetic controls. In order to confirm epigenetic regulation of innate genes we used a panel of HAT, HDAC and histone demethylase inhibitors. We initially studied the impact of cytokines on a range of innate anti-viral genes. RIG1 was differentially expressed and reductions in expression associated with higher viral titres. IFNy priming induced increases in RIG1 mRNA at 48 h that correlated at the promoter with enrichment of H3K9ac and RNApolII (active-promoters) and reduction of H3K9me3 (repressive-promoters). We observed a statistically significant increase of RIG1 expression by IFNγ when co-incubated with SAHA (HDAC I and II inhibitors) and JIB-04 (Pan-Jumanji histone demethylase inhibitor). No effects of Th2 priming were seen at the level of antiviral responses. This in-vitro study suggests the inflammatory environment of naive epithelial cells can induce epigenetic modulation of innate immune responses at the level of histone methylation and acetylation and hence potentially lead to long term impacts on anti-viral immunity. The presence of a Th1 milieu appears key to the development of effective anti-viral responses.

Long Noncoding RNA NEAT1-Dependent SFPQ Relocation from Promoter Region to Paraspeckle Mediates IL8 Expression upon Immune Stimuli

Although thousands of long noncoding RNAs (lncRNAs) are localized in the nucleus, only a few dozen have been functionally characterized. Here we show that nuclear enriched abundant transcript 1 (NEAT1), an essential lncRNA for the formation of nuclear body paraspeckles, is induced by influenza virus and herpes simplex virus infection as well as by Toll-like receptor3-p38 pathway-triggered poly I:C stimulation, resulting in excess formation of paraspeckles. We found that NEAT1 facilitates the expression of antiviral genes including cytokines such as interleukin-8 (IL8). We found that splicing factor proline/glutamine-rich (SFPQ), a NEAT1-binding paraspeckle protein, is a repressor of IL8 transcription, and that NEAT1 induction relocates SFPQ from the IL8 promoter to the paraspeckles, leading to transcriptional activation of IL8. Together, our data show that NEAT1 plays an important role in the innate immune response through the transcriptional regulation of antiviral genes by the stimulus-responsive cooperative action of NEAT1 and SFPQ.

84 : Extensive collaboration of immune master regulators IRF3 and NFκB in RNA Pol II recruitment and pause-release in human innate antiviral transcription

The eukaryotic transcription factors, IRF3 and NF κ B, regulate immunity and inflammatory responsive genes. Both factors are activated by external stimuli that evoke strong immune and/or inflammatory responses, including virus infection, to translocate to the nucleus and bind their genomic target sites. These two proteins are critical regulators of immunity and inflammatory responses, control diverse normal cellular functions, and aberrations in their activity contribute to pathologies including inflammatory diseases and cancer. Despite the wealth of information regarding the ability of IRF3 and NF κ B to regulate the expression of IFNB1 and other individual target genes, their relative contributions to overall virus-activated transcription, their degree of overlap within the antiviral gene regulation network, and their breadth of target sites throughout the genome are under-investigated. The mechanisms used in regulating antiviral Pol II recruitment, initiation, and elongation at specific targets, as well as their abilities to regulate non-coding and protein-coding genes remain poorly understood. To investigate the mechanisms used to mediate RNA Polymerase II (Pol II) recruitment, initiation, and elongation that contribute to the human antiviral gene regulatory network, a comprehensive genome-wide ChIP-seq analysis was conducted during the initial phase of virus infection to provide a detailed and quantitative genome-wide analysis of transcriptional regulation of the cellular antiviral response. Results reveal extensive integration of IRF3 and NF κ B with Pol II and its associated machinery, and implicate new transcriptional partners for antiviral gene regulation. In addition to mRNA-encoding loci, a majority of IRF3 and NF κ B target sites stimulate RNA production at novel genomic regions not previously associated with antiviral transcription through a combination of de novo polymerase recruitment and release of paused Pol II. These factors work together to tightly regulate gene activation essential to cellular innate immunity.

Acetylation-Dependent Signal Transduction for Type I Interferon Receptor

Cytokine-activated receptors initiate intracellular signaling by recruiting protein kinases that phosphorylate the receptors on tyrosine residues, thus enabling docking of SH2 domain-bearing activating factors. Here we report that in response to type 1 interferon (IFNalpha), IFNalpha receptors recruit cytoplasmic CREB-binding protein (CBP). By binding to IFNalphaR2 within the region where two adjacent proline boxes bear phospho-Ser364 and phospho-Ser384, CBP acetylates IFNalphaR2 on Lys399, which in turn serves as the docking site for interferon regulatory factor 9 (IRF9). IRF9 interacts with the acetyl-Lys399 motif by means of its IRF homology2 (IH2) domain, leading to formation of the ISGF3 complex that includes IRF9, STAT1, and STAT2. All three components are acetylated by CBP. Remarkably, acetylation within the DNA-binding domain (DBD) of both IRF9 and STAT2 is critical for the ISGF3 complex activation and its associated antiviral gene regulation. These results have significant implications concerning the central role of acetylation in cytokine receptor signal transduction.