Search results for "Interferons"

The murine cytomegalovirus M35 protein antagonizes type I IFN induction downstream of pattern recognition receptors by targeting NF-κB mediated trans…

2017

The type I interferon (IFN) response is imperative for the establishment of the early antiviral immune response. Here we report the identification of the first type I IFN antagonist encoded by murine cytomegalovirus (MCMV) that shuts down signaling following pattern recognition receptor (PRR) sensing. Screening of an MCMV open reading frame (ORF) library identified M35 as a novel and strong negative modulator of IFNβ promoter induction following activation of both RNA and DNA cytoplasmic PRR. Additionally, M35 inhibits the proinflammatory cytokine response downstream of Toll-like receptors (TLR). Using a series of luciferase-based reporters with specific transcription factor binding sites, …

The role of spatial structure in the evolution of viral innate immunity evasion: A diffusion-reaction cellular automaton model

2020

Most viruses have evolved strategies for preventing interferon (IFN) secretion and evading innate immunity. Recent work has shown that viral shutdown of IFN secretion can be viewed as a social trait, since the ability of a given virus to evade IFN-mediated immunity depends on the phenotype of neighbor viruses. Following this idea, we investigate the role of spatial structure in the evolution of innate immunity evasion. For this, we model IFN signaling and viral spread using a spatially explicit approximation that combines a diffusion-reaction model and cellular automaton. Our results indicate that the benefits of preventing IFN secretion for a virus are strongly determined by spatial struct…

Impact of PNPLA3 and IFNL3 polymorphisms on hepatic steatosis in Asian patients with chronic hepatitis C.

2017

Background and aims A recent meta-analysis revealed that the genotype PNPLA3 rs738409 GG is associated with a higher risk of hepatic steatosis (HS) in Caucasian patients with chronic hepatitis C (CHC). However, controversial results were found regarding Asian populations. Furthermore, previous studies have shown a negative association between interferon lambda 3 (IFNL3) rs12979860 CC and HS in Caucasian CHC patients, but there have been no reports indicating any such association in Asian populations. In this study, then, we investigated the association of PNPLA3 and IFNL3 polymorphisms with HS in Asian CHC patients. Methods We enrolled consecutive CHC patients who underwent liver biopsy pri…

Constrained evolvability of interferon suppression in an RNA virus.

2016

AbstractInnate immunity responses controlled by interferon (IFN) are believed to constitute a major selective pressure shaping viral evolution. Viruses encode a variety of IFN suppressors, but these are often multifunctional proteins that also play essential roles in other steps of the viral infection cycle, possibly limiting their evolvability. Here, we experimentally evolved a vesicular stomatitis virus (VSV) mutant carrying a defect in the matrix protein (M∆51) that abolishes IFN suppression and that has been previously used in the context of oncolytic virotherapy. Serial transfers of this virus in normal, IFN-secreting cells led to a modest recovery of IFN blocking capacity and to weak …

High sCD36 plasma level is associated with steatosis and its severity in patients with genotype 1 chronic hepatitis C

2013

SUMMARY. Soluble CD36 (sCD36) plasma levels, a known marker of cardiometabolic disorders, are associated with surrogate markers of steatosis, while experimental and human studies show a link between CD36 expression in the liver and steatosis. In a cohort of patients with genotype 1 chronic hepatitis C (G1 CHC), we tested the association of sCD36 plasma levels with host and viral factors and sustained virological response (SVR). One hundred and seventy-five consecutive biopsy-proven patients were studied. sCD36 plasma levels were assessed by an in-house ELISA. All biopsies were scored by one pathologist for staging and grading (Scheuer) and graded for steatosis, which was considered moderate…

Schistosomiasis and antiviral treatment of chronic hepatitis C

2003

Low vitamin D serum level is related to severe fibrosis and low responsiveness to interferon-based therapy in genotype 1 chronic hepatitis C

2010

UNLABELLED 25-Hydroxyvitamin D (25[OH]D) can potentially interfere with inflammatory response and fibrogenesis. Its role in disease progression in chronic hepatitis C (CHC) and its relation with histological and sustained virological response (SVR) to therapy are unknown. One hundred ninety-seven patients with biopsy-proven genotype 1 (G1) CHC and 49 healthy subjects matched by age and sex were consecutively evaluated. One hundred sixty-seven patients underwent antiviral therapy with pegylated interferon plus ribavirin. The 25(OH)D serum levels were measured by high-pressure liquid chromatography. Tissue expression of cytochrome (CY) P27A1 and CYP2R1, liver 25-hydroxylating enzymes, were as…

Survival of patients with HCV cirrhosis and sustained virologic response is similar to the general population.

2016

Background & Aims: Life expectancy of patients with compensated hepatitis C virus (HCV) cirrhosis achieving sustained virologic response (SVR) is limited by liver events as compared to the general population. Thus, survival benefit of SVR remains to be measured. Methods: The study includes prospective surveillance data from three cohorts of Italian patients with compensated HCV cirrhosis who achieved SVR on an interferon-based (IFN) regimen, compared to simultaneously observed non-SVR, untreated and decompensated patients. Overall survival was calculated from the date of start of IFN to death. The number of deaths expected during the at-risk period was determined by applying age- and se…

IL28B polymorphisms influence stage of fibrosis and spontaneous or interferon-induced viral clearance in thalassemia patients with hepatitis C virus …

2012

Background. Polymorphisms in the interleukin-28B are important determinants in the spontaneous and drug-induced control of hepatitis C virus infection. Design and Methods. We assessed the association of rs8099917 and rs12979860 polymorphisms with spontaneous viral clearance, severity of liver fibrosis, and response to interferon-monotherapy in 245 Thalassemia Major patients with Hepatitis C Virus infection. Results. Ninety-eight patients (40%) had a spontaneous viral clearance, while 147 patients (60%) developed a chronic infection. Spontaneous viral clearance was more frequent among patients with the T/T genotype of rs8099917 polymorphism (OR 2.130; p=0.008) or C/C genotype of rs12979860 p…

Type I interferons as the potential mechanism linking mRNA COVID-19 vaccines to Bell's palsy

2021

Therapies - Sous presse. Epreuves corrigees par l'auteur. Disponible en ligne depuis le mardi 13 avril 2021