Real-life 3D therapy failure: Analysis of NS5A 93H RAS plus 108 K polymorphism in complex with ombitasvir by molecular modeling.

We report a real-life 3D therapy failure in a patient treated with ombitasvir (OMV)/paritaprevir/ritonavir and dasabuvir without ribavirin (3D-R). He had therapy failure at week 12 after the end of treatment. We detected resistance-associated substitutions (RASs) plus polymorphisms on NS3, NS5A, and NS5B target regions by population sequencing (15% cut-off) at baseline, at relapse and during follow-up. About this, NS5A RASs generally persist longer than resistances in the other target genes and may impact treatment outcome. Therefore, to evaluate OMV drug-resistance mechanism, we studied the acquired RAS plus polymorphisms on NS5A phosphoprotein by computational studies. OMV showed a higher affinity towards baseline and 93H/108 K mutant structure (follow-up) with respect to 93H/R108 mutant structure (relapse) on phosphoprotein. By Molecular Dynamics simulations (MDs), structural information about the protein stability in presence of OMV were observed. According to our data, molecular modeling approach has proved to be a powerful method to evaluate the impact of these RASs plus specific amino acid (AA) changes on phosphoprotein.

Evaluation of cardiac function by global longitudinal strain before and after treatment with sofosbuvir-based regimens in HCV infected patients.

BACKGROUND: Possible cardiotoxicity of sofosbuvir in humans has not been demonstrated yet. Also, since HCV can exert deleterious effects on hearth function, it is of interest to know whether HCV eradication provides any benefits using global longitudinal strain (GLS), a measure of left ventricular function more reliable than ejection fraction (EF). METHODS: Patients eligible for treatment with the combination therapy for HCV were invited to perform a transthoracic cardiac ultrasound at four different time points: before starting treatment, after one month, at the end of treatment and, after six month. Left ventricular function was measured with both EF and GLS. RESULTS: From March 2015 to December 2016, 82 patients were enrolled. Fifty-six percent patients were males. Mean age was 66.12 (SD: 9.25) years. About 20% patients did not present any cardiovascular risk factors or comorbidities. A worsening trend of GLS was observed. Variations were not found to be statistically significant when EF was studied along the follow-up. However, when GLS was studied, its variations were found to be statistically significant indicating a worsening effect, albeit with different trends in patients who underwent treatment for three months compared to six months. Worsening of GLS was found to be statistically significant even after adjusting for body mass index and liver fibrosis, independently from treatment duration. CONCLUSIONS: Our results showed unexpected worsening of left ventricular function when measured through GLS after HCV treatment response induced by DAAs including sofosbuvir. Although this result is not proven to be clinically significant, the safety profile of sofosbuvir-based regimens needs to be studied further.

Increase of Vascular Endothelial Growth Factor and Decrease of MCP-1 and Some Updated Epidemiology Aspects of Cystic Echinococcosis Human Cases in Calabria Region.

We aim to investigate some of the pathogenetic mediators of the human echinococcosis and to obtain updated epidemiological findings on cases of echinococcosis in Calabria, Southern Italy. Echinococcosis diagnosis was based on imaging, serological investigations, and molecular assay. Indeed, real-time PCR indicated the presence of G2/G3 genotypes of Echinococcus granulosus complex. Regarding pathogenesis, a relevant novel tool of immune depression should be deemed the reduced level of serum MCP-1. Also, we found a previously unreported VEGF, possibly associated with neovascularization requested by the parasite cyst metabolism. Cytokine profiles suggest a bias of the immunity toward Th2 and Treg responses. Nitric oxide levels exhibited a significant decrease one week after therapy versus basal level measured before surgery and/or chemotherapy. An increase of serum total IgE class and IgG4 subclass was found in Echinococcus-positive patients versus controls. Our data demonstrated an endemic spreading, at least in the province of Catanzaro and neighboring Calabria territories, for such parasitosis with the novel issue of the number of female overcoming male cases. In conclusion, the novel findings of this study were the increased VEGF and the reduced serum MCP-1 in the studied cases, as well as the number of Echinococcus-infected females overcoming the infected males.

Implications of hepatitis C virus subtype 1a migration patterns for virus genetic sequencing policies in Italy.

BACKGROUND: In-depth phylogeographic analysis can reveal migration patterns relevant for public health planning. Here, as a model, we focused on the provenance, in the current Italian HCV subtype 1a epidemic, of the NS3 resistance-associated variant (RAV) Q80K, known to interfere with the action of NS3/4A protease inhibitor simeprevir. HCV1a migration patterns were analysed using Bayesian phylodynamic tools, capitalising on newly generated and publicly available time and geo-referenced NS3 encoding virus genetic sequence data. RESULTS: Our results showed that both immigration and local circulation fuel the current Italian HCV1a epidemic. The United States and European continental lineages dominate import into Italy, with the latter taking the lead from the 1970s onwards. Since similar migration patterns were found for Q80K and other lineages, no clear differentiation of the risk for failing simeprevir can be made between patients based on their migration and travel history. Importantly, since HCV only occasionally recombines, these results are readily transferable to the genetic sequencing policy concerning NS5A RAVs. CONCLUSIONS: The patient migration and travel history cannot be used to target only part of the HCV1a infected population for drug resistance testing before start of antiviral therapy. Consequently, it may be cost-effective to expand genotyping efforts to all HCV1a infected patients eligible for simeprevir-based therapies.

Temperature-dependent regulation of the Ochrobactrum anthropi proteome.

Ochrobactrum anthropi is a Gram-negative rod belonging to the Brucellaceae family, able to colonize a variety of environments, and actually reported as a human opportunistic pathogen. Despite its low virulence, the bacterium causes a growing number of hospital-acquired infections mainly, but not exclusively, in immunocompromised patients. The aim of this study was to obtain an overview of the global proteome changes occurring in O. anthropi in response to different growth temperatures, in order to achieve a major understanding of the mechanisms by which the bacterium adapts to different habitats and to identify some potential virulence factors. Combined quantitative mass spectrometry-based proteomics and bioinformatics approaches were carried out on two O. anthropi strains grown at temperatures miming soil/plants habitat (25°C) and human host environment (37°C), respectively. Proteomic analysis led to the identification of over 150 differentially expressed proteins in both strains, out of over 1200 total protein identifications. Among them, proteins responsible for heat shock response (DnaK, GrpE), motility (FliC, FlgG, FlgE), and putative virulence factors (TolB) were identified. The study represents the first quantitative proteomic analysis of O. anthropi performed by high-resolution quantitative mass spectrometry.

Control of carbapenem-resistant Acinetobacter baumannii outbreak in an intensive care unit of a teaching hospital in Southern Italy.

BACKGROUND: Acinetobacter baumannii is an opportunistic pathogen that has become a major cause of concern, since it is a frequent cause of healthcare-associated infections (HAIs). The aim of the study was to describe the occurrence, the management and the control of an outbreak that occurred in an intensive care unit (ICU) of a teaching hospital in Southern Italy caused by multiple strains of extensively drug-resistant A. baumannii (XDRAB). METHODS: Case-patient was defined as a patient with an healthcare-associated infection caused by an XDRAB isolate identified in a clinically significant culture. Environmental samples were collected from different surfaces. The isolates were identified by typical Gram stain morphology, using the Vitek 2 system (bioMérieux, France) and by MALDI-TOF MS mass spectrometry (bioMèrieux, France). Genotyping was performed through rep-PCR analysis. RESULTS: A patient presented an XDRAB ventilator-associated pneumonia at admission and was managed with strict isolation precautions until discharge. Five patients had a ventilator-associated pneumonia and two had a central line-associated bloodstream infection. Of the environmental samples, 1 sample obtained from the side of the bed of an infected patient yielded growth of XDRAB. Infection control measures were adopted. Rep-PCR analysis identified four patterns. CONCLUSIONS: The integration of epidemiological and microbiological data and the application of infection control measures were crucial to bring such an outbreak to a rapid halt. The distinctive characteristic of this study was the complex molecular pattern of the outbreak, which subsided in a short period of time due to adherence to infection-control measures, confirming the fundamental role of molecular typing in the comprehension of outbreaks dynamics and of integrated control interventions for the interruption of epidemic events.

Detection of Natural Resistance-Associated Substitutions by Ion Semiconductor Technology in HCV1b Positive, Direct-Acting Antiviral Agents-Naïve Patients.

Naturally occurring resistance-associated substitutions (RASs) can negatively impact the response to direct-acting antivirals (DAAs) agents-based therapies for hepatitis C virus (HCV) infection. Herein, we set out to characterize the RASs in the HCV1b genome from serum samples of DAA-naïve patients in the context of the SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology, 2014) project. We deep-sequenced the NS3/4A protease region of the viral population using the Ion Torrent Personal Genome Machine, and patient-specific majority rule consensus sequence summaries were constructed with a combination of freely available next generation sequencing data analysis software. We detected NS3/4A protease major and minor variants associated with resistance to boceprevir (V36L), telaprevir (V36L, I132V), simeprevir (V36L), and grazoprevir (V36L, V170I). Furthermore, we sequenced part of HCV NS5B polymerase using Sanger-sequencing and detected a natural RAS for dasabuvir (C316N). This mutation could be important for treatment strategies in cases of previous therapy failure.

Gut inflammation and immunity: what is the role of the human gut virome?

The human virome comprises viruses that infect host cells, virus-derived elements in our chromosomes, and viruses that infect other organisms, including bacteriophages and plant viruses. The development of high-throughput sequencing techniques has shown that the human gut microbiome is a complex community in which the virome plays a crucial role into regulation of intestinal immunity and homeostasis. Nevertheless, the size of the human virome is still poorly understood. Indeed the enteric virome is in a continuous and dynamic equilibrium with other components of the gut microbiome and the gut immune system, an interaction that may influence the health and disease of the host. We review recent evidence on the viruses found in the gastrointestinal tract, discussing their interactions with the resident bacterial microbiota and the host immune system, in order to explore the potential impact of the virome on human health.

Virological Mechanisms in the Coinfection between HIV and HCV.

Due to shared transmission routes, coinfection with Hepatitis C Virus (HCV) is common in patients infected by Human Immunodeficiency Virus (HIV). The immune-pathogenesis of liver disease in HIV/HCV coinfected patients is a multifactorial process. Several studies demonstrated that HIV worsens the course of HCV infection, increasing the risk of cirrhosis and hepatocellular carcinoma. Also, HCV might increase immunological defects due to HIV and risk of comorbidities. A specific cross-talk among HIV and HCV proteins in coinfected patients modulates the natural history, the immune responses, and the life cycle of both viruses. These effects are mediated by immune mechanisms and by a cross-talk between the two viruses which could interfere with host defense mechanisms. In this review, we focus on some virological/immunological mechanisms of the pathogenetic interactions between HIV and HCV in the human host.

Typing of Ochrobactrum anthropi clinical isolates using automated repetitive extragenic palindromic-polymerase chain reaction DNA fingerprinting and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry.

BACKGROUND: Ochrobactrum anthropi (O. anthropi), is a non-fermenting gram-negative bacillus usually found in the environment. Nevertheless, during the past decade it has been identified as pathogenic to immunocompromised patients. In this study, we assessed the usefulness of the automated repetitive extragenic palindromic-polymerase chain reaction (rep-PCR-based DiversiLab™ system, bioMèrieux, France) and of matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF MS) for typing of twentythree O. anthropi clinical isolates that we found over a four-months period (from April 2011 to August 2011) in bacteriemic patients admitted in the same operative unit of our hospital. Pulsed-field gel electrophoresis (PFGE), commonly accepted as the gold standard technique for typing, was also used. Analysis was carried out using the Pearson correlation coefficient to determine the distance matrice and the unweighted pair group method with arithmetic mean (UPGMA) to generate dendogram. RESULTS: Rep-PCR analysis identified four different patterns: three that clustered together with 97% or more pattern similarity, and one whose members showed < 95% pattern similarity. Interestingly, strains isolated later (from 11/06/2011 to 24/08/2011) displayed a pattern with 99% similarity. MALDI-TOF MS evaluation clustered the twentythree strains of O. anthropi into a single group containing four distinct subgroups, each comprising the majority of strains clustering below 5 distance levels, indicating a high similarity between the isolates. CONCLUSIONS: Our results indicate that these isolates are clonally-related and the methods used afforded a valuable contribution to the epidemiology, prevention and control of the infections caused by this pathogen.

Update on different aspects of HCV variability: focus on NS5B polymerase.

The study of hepatitis C virus (HCV) genotypes/subtypes, quasispecies and recombinants obtained by virus genome sequencing are important for epidemiological studies, to trace the source of infection, for development of new direct acting antivirals (DAAs) therapy and for understanding antiviral selection pressures. The HCV NS5B gene encodes a polymerase, which is responsible for virus replication and is a potential target for the development of antiviral agents. Many studies for classification of HCV use a particular segment of the NS5B gene, in addition to other specific regions, and phylogenetic analysis. Actually, some nucleoside/nucleotide analogues and non-nucleoside inhibitors target NS5B protein. This review focuses on HCV variability, phylogenetic analysis and the role of NS5B in the virus-host interactions.

Interleukin 27 polymorphisms in HCV RNA positive patients: is there an impact on response to interferon therapy?

BACKGROUND: Interleukin 27 (IL-27) has pleiotropic properties that can either limit or enhance immune responses. Recent studies revealed that single nucleotide polymorphisms (SNPs) of the IL-27 promoter region modulate the development of infectious diseases and individual's susceptibility to therapeutic response. Little is known about the relationship between IL-27 single nucleotide polymorphisms and therapy response in patients infected by hepatitis C virus (HCV). In this study we have investigated the potential role of SNPs in the promoter region of IL27 p28 gene (alleles rs153109) on the outcome of HCV infected patients. METHODS: rs153109, corresponding to position c.-964A>G of the IL-27 locus, was amplified from genomic DNA extracted from 15 patients with chronic hepatitis C stratified by sustained viral response (SVR), relapser and non-responder, after treatment with peginterferon-α (PegIFN- α) combined with ribavirin (RBV). Amplification products were studied by direct sequencing. RESULTS: This method has been applied in a preliminary study on patients with chronic hepatitis C to provide information for a standardized assay useful to genotyping of rs153109 SNPs of IL-27p28. The genotype distribution of the c.-964 A>G polymorphism was more present in patients who did not achieve a SVR. By contrast, the genotype G/G was absent in non-responder and relapser patients. Moreover, the analysis of allelic distribution of rs153109 highlighted a predominance of allele A in all genotypes in spite of allele G. CONCLUSIONS: Our work provides preliminary information for a standardized method potentially useful for genotyping rs153109, and suggests its utility as a candidate approach to evaluate IL-27 p28 polymorphisms as additional clinical predictors of response to therapies in HCV infected patients.

Challenging clinical cases in HCV infection.

We present clinical cases, which underline some difficulties in diagnosis and treatment of hepatitis C virus (HCV) infection. Case report #1 shows a patient who avoided clinical follow-up for HCV until the development of hepatocellular carcinoma. In this patient, non-invasive procedures did not allow to make a differential diagnosis between hydatidosis and hepatocellular carcinoma but diagnosis was only made with liver biopsy.

Present, old and future strategies for anti-HCV treatment in patients infected by genotype-1: estimation of the drug costs in the Calabria Region in the era of the directly acting antivirals.

BACKGROUND: In Italy, anti-HCV drugs are provided free of charge by the National Health System. Since 2011, three drug regimens including a directly acting antiviral (DAA) are considered the gold standard for HCV treatment. However, these drugs add a significant cost (roughly €26,000) to the combination of pegylated-interferon-α/ribavirin (PEG-IFN/RBV), which before DAA represented the unique treatment. To provide the National Health System potential useful information, we estimated costs to provide anti-HCV drugs to treat a population experienced for PEG-INF/RBV. METHODS: Genotype 1 HCV mono-infected or HIV/HCV co-infected individuals who were treated with PEG-IFN/RBV between 2008 and 2013 were included. The cost to treat these patients with PEG-IFN/RBV was calculated (cost 1). We also estimated costs if we had to treat these patients with a lead-in period of PEG-INF/RBV followed by PEG-IFN/RBV and a DAA in naïves (cost 2), in addition to cost 1 plus the estimated cost to re-treat with PEG-IFN/RBV and a DAA patients who had a relapse or a non response (cost 3). Moreover, all costs were normalized by SVR. Rates of foreseen response with DAA were obtained from literature data. RESULTS: The overall study population consisted of 104 patients. The rate of sustained virological response (SVR) was 55%, while it was estimated that SVR would be obtained in 75% of patients with a lead-in period with PEG-IFN/RBV followed by a DAA combination, and in 78% if this treatment is used to re-treat experienced patients with a DAA. Drug costs associated with these treatments were: €1,214,283 for cost 1, €3,474,977 for cost 2 and €3,002,095 for cost 3. Costs per SVR achieved were: €22,284 for cost 1, €44,643 for cost 2 and €38,322 for cost 3. CONCLUSIONS: Treatments including DAAs achieve a SVR in more patients than PEG-IFN/RBV but they cost around three times more than PEG-IFN/RBV alone regimens. Also, cost per SVR is almost twofold greater than PEG-IFN/RBV regimens. Therefore, it is mandatory to implement use of DAA in clinical practice, but the National Health System should allocate adequate resources to provide drugs, which challenges sustainability. Cost reduction for anti-HCV drugs should be pursued.

Update on epidemiology of HCV in Italy: focus on the Calabria Region.

The epidemiological profile of HCV infection is evolving in Europe, as well as in Italy. We have previously showed genotype distributions and their dynamics in 2,153 HCV RNA positive patients living in Calabria, Southern Italy, over 11 years. In this study, we extend and update this information by evaluating a hospital-based cohort of 945 HCV RNA positive patients attending five hospitals in the Calabria Region from January 2011 to August 2013. We assessed rates of HCV genotypes according to age and gender and the dynamics of HCV genotype distribution over the 3-year period studied. Data showed that genotype 1b is the most prevalent, followed by subtypes 2a/2c and genotype 3. Genotype 4 exhibited an increase between 2011 and 2013. Also, we found a significant decrease in the median age of subjects infected with HCV genotype 3 and 4 during the period studied. Since HCV genotypes are important in epidemiology, pathogenesis and response to antiviral therapy, a continuous epidemiological surveillance is needed.

Chronic neuroborreliosis by B. garinii: an unusual case presenting with epilepsy and multifocal brain MRI lesions.

Late/chronic Lyme neuroborreliosis (LNB) represents a challenging entity whose diagnosis requires a combination of clinical and laboratory findings, surrounded by much controversy. Here we describe a patient who had a peculiar form of late LNB with CNS lesions shown by magnetic resonance imaging (MRI), and epileptic seizures, etiologically diagnosed by conventional and molecular methods. The current case provides evidence that patients presenting with epileptic seizures and MRI-detected multifocal lesions, particularly when a facial palsy has also occurred, should raise the suspicion of LNB, as this diagnosis has important implications for treatment and prognosis.

Shotgun proteomic analysis of two Bartonella quintana strains.

This study reports the first extensive shotgun analysis of the Bartonella quintana proteome. Proteins extracted from two B. quintana strains, Oklahoma and JK31, were analyzed in triplicate analyses by a bottom-up approach consisting of tryptic digestion in SDS-containing buffer, strong cation-exchange StageTip fractionation, and nano-LC-MS/MS analysis. By setting spectral false discovery rate below 0.5%, 548 unique proteins were identified overall, of which 409 protein identifications were shared between the two strains. The data set, which achieves the highest proteome coverage for B. quintana to date, could be exploited for the quantitative analysis of a selected subset of target proteins.

Impact of interleukin-10, soluble CD25 and interferon-γ on the prognosis and early diagnosis of bacteremic systemic inflammatory response syndrome: a prospective observational study.

INTRODUCTION: The pathophysiology of sepsis consists of two phases. A first phase characterized by a substantial increase of pro-inflammatory mediators including cytokines and systemic inflammatory markers, and a second phase (immunoparalysis, immunodysregulation) associated with the rise of anti-inflammatory mediators. In this study we prospectively analyzed 52 consecutive patients with diagnosis of systemic inflammatory response syndrome (SIRS) at hospital admission to evaluate prognostic and early diagnostic performance of interleukin-10 (IL-10), soluble CD25 (sCD25) and interferon-γ (IFN-γ) and to confirm the prognostic accuracy of the sequential organ failure assessment (SOFA) score. METHODS: Patients were divided in two groups (group 1, n=28 patients with bacteremic SIRS and group 2, n=24 patients with non-bacteremic SIRS) and then stratified into survivors (n=39) and nonsurvivors (n=13). Serum markers were evaluated on the day of hospital admission (D-1) and on the 7th day of hospital stay (D-7). Concentration of sCD25 was evaluated by a sandwich ELISA kit. Levels of IL-10 and IFN-γ were quantified by a cytokine biochip array by the evidence investigator analyzer. Differences between groups were established by the Mann-Whitney test. Accuracy, sensitivity and specificity of diagnostic markers were evaluated by the receiver-operating characteristic curve analysis. Multivariate analysis was carried out to evaluate whether studied biomarkers are independent predictors of poor outcome in prognosis, and of bacteremic SIRS in diagnosis. RESULTS: IL-10, sCD25 and SOFA scores of survivors and nonsurvivors were significantly different both at D-1 (P=0.0014; P=0.014 and P=0.0311 respectively) and at D-7 (P=0.0002, P=0.014 and P=0.0012 respectively). Between the above groups IFN-γ level was significantly different only at D-7 (P=0.0013). Moreover IL-10 and sCD25 were significantly higher in bacteremic versus non-bacteremic SIRS patients at D-1 and at D-7 (P<0.05). IFN-γ values showed a significant decrease (P<0.05) in patients of group 1 only at D-7. The diagnostic accuracy of IL-10 and sCD25 was confirmed by the analysis of the AUROCC at D-1 and D-7 respectively. Multivariate analysis revealed that sCD25 and IL-10 are independent predictors of a poor outcome for our patients during the first day of hospital admission. CONCLUSIONS: IL-10 and sCD25 gave a significant contribution to prognostic evaluation and early diagnosis of bacteremic SIRS. SOFA score appeared to be a reliable prognostic tool in this subset of patients.

Changing epidemiology of hepatitis C in Italy: a population-based survey in a historically high endemic area.

BACKGROUND: General population data on hepatitis C virus (HCV) prevalence in Italy come mostly from studies conducted in small towns. The highest rates have consistently been found in southern regions, especially in Calabria. Herein, we aimed to determine HCV prevalence, awareness, and risk factors in the general population of Catanzaro, the capital city of Calabria, Italy. METHODS: A stratified probability-based random sample of adult population was drawn from the Census. Anti-HCV and HCV-RNA were assayed. Data on sociodemographycs, risk factors and awareness of infection status were also collected. Crude and age and sex directly standardized rates (DSR), using Catanzaro's general population as standard, were calculated. Log binomial regressions with sampling weights was used to identify independent predictors of infection. RESULTS: The final study population consisted of 1003 people. Of them 27 (2.69%; 95% confidence interval, [CI] 1.78-3.89) (DSR: 2.34%; 95% CI: 1.37-3.30) and 9 (0.9%; 95% CI: 0.41-1.70) (DSR: 0.79%; 95% CI: 0.21-1.37) were anti-HCV and HCV RNA positive, respectively. Most HCV-positive participants were older people. Age ≥65 and past use of illicit drugs were both positive independent predictors of anti-HCV positivity, while female sex was an independent protective predictor of infection. Only 9 (33.3%) of anti-HCV positive participants had awareness of their status. CONCLUSIONS: We detected a much lower anti-HCV prevalence than those previously found in Calabria, along with a substantial change in HCV transmission modes. Infected people were almost only elderly and mostly unaware of their infection. Improving diagnosis and linkage to care for these infected persons would be needed.

Human papillomavirus type 16 E5 protein induces expression of beta interferon through interferon regulatory factor 1 in human keratinocytes.

Crucial steps in high-risk human papillomavirus (HR-HPV)-related carcinogenesis are the integration of HR-HPV into the host genome and loss of viral episomes. The mechanisms that promote cervical neoplastic progression are, however, not clearly understood. During HR-HPV infection, the HPV E5 protein is expressed in precancerous stages but not after viral integration. Given that it has been reported that loss of HPV16 episomes and cervical tumor progression are associated with increased expression of antiviral genes that are inducible by type I interferon (IFN), we asked whether E5, expressed in early phases of cervical carcinogenesis, affects IFN-ß signaling. We show that the HPV type 16 (HPV16) E5 protein expression per se stimulates IFN-ß expression. This stimulation is specifically mediated by the induction of interferon regulatory factor 1 (IRF-1) which, in turn, induces transcriptional activation of IRF-1-targeted interferon-stimulated genes (ISGs) as double-stranded RNA-dependent protein kinase R (PKR) and caspase 8. Our data show a new and unexpected role for HR-HPV E5 protein and indicate that HPV16 E5 may contribute to the mechanisms responsible for cervical carcinogenesis in part via stimulation of IFN-ß and an IFN signature, with IRF-1 playing a pivotal role. HPV16 E5 and IRF-1 may thus serve as potential therapeutic targets in HPV-associated premalignant lesions.