Human influenza A virus causes myocardial and cardiac-specific conduction system infections associated with early inflammation and premature death.

AIMS: Human influenza A virus (hIAV) infection is associated with important cardiovascular complications, although cardiac infection pathophysiology is poorly understood. We aimed to study the ability of hIAV of different pathogenicity to infect the mouse heart, and establish the relationship between the infective capacity and the associated in vivo, cellular and molecular alterations. METHODS AND RESULTS: We evaluated lung and heart viral titres in mice infected with either one of several hIAV strains inoculated intranasally. 3D reconstructions of infected cardiac tissue were used to identify viral proteins inside mouse cardiomyocytes, Purkinje cells, and cardiac vessels. Viral replication was measured in mouse cultured cardiomyocytes. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were used to confirm infection and study underlying molecular alterations associated with the in vivo electrophysiological phenotype. Pathogenic and attenuated hIAV strains infected and replicated in cardiomyocytes, Purkinje cells, and hiPSC-CMs. The infection was also present in cardiac endothelial cells. Remarkably, lung viral titres did not statistically correlate with viral titres in the mouse heart. The highly pathogenic human recombinant virus PAmut showed faster replication, higher level of inflammatory cytokines in cardiac tissue and higher viral titres in cardiac HL-1 mouse cells and hiPSC-CMs compared with PB2mut-attenuated virus. Correspondingly, cardiac conduction alterations were especially pronounced in PAmut-infected mice, associated with high mortality rates, compared with PB2mut-infected animals. Consistently, connexin43 and NaV1.5 expression decreased acutely in hiPSC-CMs infected with PAmut virus. YEM1L protease also decreased more rapidly and to lower levels in PAmut-infected hiPSC-CMs compared with PB2mut-infected cells, consistent with mitochondrial dysfunction. Human IAV infection did not increase myocardial fibrosis at 4-day post-infection, although PAmut-infected mice showed an early increase in mRNAs expression of lysyl oxidase. CONCLUSION: Human IAV can infect the heart and cardiac-specific conduction system, which may contribute to cardiac complications and premature death.

Interferon- Stimulation Elicited by the Influenza Virus Is Regulated by the Histone Methylase Dot1L through the RIG-I-TRIM25 Signaling Axis.

Influenza virus infection increases the methylation of lysine 79 of histone 3 catalyzed by the Dot1L enzyme. The role of Dot1L against infections was highlighted by an increase of influenza A and vesicular stomatitis virus replication in Dot1L-inhibited cells mediated by a decreased antiviral response. Interferon-beta (IFN-ß) reporter assays indicate that Dot1L is involved in the control of retinoic acid-inducible geneI protein (RIG-I) signaling. Accordingly, Dot1L inhibition decreases the IFN-ß promoter stimulation and RIG-I- mitochondria-associated viral sensor (RIG-I-MAVS) association upon viral infection. Replication of an influenza A virus lacking NS1 (delNS1), incapable of counteracting the antiviral response, is not affected by Dot1L inhibition. Consequently, RIG-I-MAVS association and nuclear factor-B (NF-κ nuclear translocation, are not affected by the Dot1L inhibition in delNS1 infected cells. Restoration of NS1 expression in trans also reinstated Dot1L as a regulator of the RIG-I-dependent signaling in delNS1 infections. Interferon-inducible E3 ligase tripartite motif-containing protein 25 (TRIM25) expression increases in influenza virus infected cells, but Dot1L inhibition reduces both the TRIM25 expression and TRIM25 protein levels. TRIM25 overexpression reverses the defective innate response mediated by Dot1L inhibition elicited upon virus infection or by overexpression of RIG-I signaling intermediates. Thus, TRIM25 is a control point of the RIG-I recognition pathway controlled by Dot1L and may have a general role in RNA viruses recognized by the RIG-I sensor.

Mutations of the segment-specific nucleotides at the 3' end of influenza virus NS segment control viral replication.

The vRNAs of influenza A viruses contain 12 and 13 nucleotide-long sequences at their 3' and 5' termini respectively that are highly conserved and constitute the vRNA promoter. These sequences and the next three segment-specific nucleotides show inverted partial complementarity and are followed by several unpaired nucleotides of poorly characterized function at the 3' end. We have performed systematic point-mutations at the segment-specific nucleotides 15-18 of the 3'-end of a NS-like vRNA segment. All NS-like vRNAs containing mutations at position 15, and some at positions 16-18 showed reduced transcription/replication efficiency in a transfection/infection system. In addition, the replication of recombinant viruses containing mutations at position 15 was impaired both in single and multi-cycle experiments. This reduction was the consequence of a decreased expression of the NS segment. The data indicate that NS1 plays a role in the transcription/replication of its own segment, which elicits a global defect on virus replication.

The DOT1L inhibitor Pinometostat decreases the host-response against infections: Considerations about its use in human therapy.

Patients with acute myeloid leukemia frequently present translocations of MLL gene. Rearrangements of MLL protein (MLL-r) in complexes that contain the histone methyltransferase DOT1L are common, which elicit abnormal methylation of lysine 79 of histone H3 at MLL target genes. Phase 1 clinical studies with pinometostat (EPZ-5676), an inhibitor of DOT1L activity, demonstrated the therapeutic potential for targeting DOT1L in MLL-r leukemia patients. We previously reported that down-regulation of DOT1L increases influenza and vesicular stomatitis virus replication and decreases the antiviral response. Here we show that DOT1L inhibition also reduces Sendai virus-induced innate response and its overexpression decreases influenza virus multiplication, reinforcing the notion of DOT1L controlling viral replication. Accordingly, genes involved in the host innate response against pathogens (RUBICON, TRIM25, BCL3) are deregulated in human lung epithelial cells treated with pinometostat. Concomitantly, deregulation of some of these genes together with that of the MicroRNA let-7B, may account for the beneficial effects of pinometostat treatment in patients with MLL-r involving DOT1L. These results support a possible increased vulnerability to infection in MLL-r leukemia patients undergoing pinometostat treatment. Close follow up of infection should be considered in pinometostat therapy to reduce some severe side effects during the treatment.

hCLE/RTRAF-HSPC117-DDX1-FAM98B: A New Cap-Binding Complex That Activates mRNA Translation.

hCLE/C14orf166/RTRAF, DDX1, and HSPC117 are components of cytoplasmic mRNA-transporting granules kinesin-associated in dendrites. They have also been found in cytoplasmic ribosome-containing RNA granules that transport specific mRNAs halted for translation until specific neuronal signals renders them accessible to the translation machinery. hCLE associates to DDX1, HSPC117, and FAM98B in HEK293T cells and all four proteins bind to cap analog-containing resins. Competition and elution experiments indicate that binding of hCLE complex to cap resins is independent of eIF4E; the cap-binding factor needed for translation. Purified hCLE free of its associated proteins binds cap with low affinity suggesting that its interacting proteins modulate its cap association. hCLE silencing reduces hCLE accumulation and that of its interacting proteins and decreases mRNA translation. hCLE-associated RNAs have been isolated and sequenced; RNAs involved in mRNA translation are specifically associated. The data suggest that RNA granules may co-transport RNAs encoding proteins involved in specific functions together with RNAs that encode proteins needed for the translation of these specific RNAs and indicate an important role for hCLE modulating mRNA translation.

Mutation S110L of H1N1 Influenza Virus Hemagglutinin: A Potent Determinant of Attenuation in the Mouse Model.

Characterization of a pandemic 2009 H1N1 influenza virus isolated from a fatal case patient (F-IAV), showed the presence of three different mutations; potential determinants of its high pathogenicity that were located in the polymerase subunits (PB2 A221T and PA D529N) and the hemagglutinin (HA S110L). Recombinant viruses containing individually or in combination the polymerase mutations in the backbone of A/California/04/09 (CAL) showed that PA D529N was clearly involved in the increased pathogenicity of the F-IAV virus. Here, we have evaluated the contribution of HA S110L to F-IAV pathogenicity, through introduction of this point mutation in CAL recombinant virus (HA mut). The HA S110L protein has similar pH stability, comparable mobility, and entry properties both in human and mouse cultured cells that wild type HA. The change HA S110L leads to a non-significant trend to reduce the replication capacity of influenza virus in tissue culture, and HA mut is better neutralized than CAL virus by monoclonal and polyclonal antibodies against HA from CAL strain. In addition, recombinant viruses containing HA S110L alone or in combination with polymerase mutations considerably increased the LD50 in infected mice. Characterization of the lungs of HA mut infected animals showed reduced lung damage and inflammation compared with CAL infected mice. Accordingly, lower virus replication, decreased presence in bronchioli and parenchyma and lower leukocytes and epithelial infected cells were found in the lungs of HA mut-infected animals. Our results indicate that, mutation HA S110L constitutes a determinant of attenuation and suggest that its interaction with components of the respiratory tract mucus and lectins, that play an important role on influenza virus outcome, may constitute a physical barrier impeding the infection of the target cells, thus compromising the infection outcome.

Adherencia al tratamiento en pacientes mayores de 65 años que sufren reingresos precoces / Treatment adherence in patients more than 65 years who experience early readmissions

Objetivo: Analizar la frecuencia del incumplimiento terapéutico en pacientes que sufren reingresos hospitalarios precoces e identificar los factores asociados al mismo. Método: Estudio observacional descriptivo de tres meses de duración (marzo-mayo de 2014). Se incluyeron todos los pacientes mayores de 65 años que reingresaron en los 3-30 días siguientes al alta hospitalaria. Fueron excluidos los reingresos programados y los reingresos en la Unidad de Cuidados Intensivos. Las variables recogidas fueron: edad, sexo, servicio médico, categoría diagnóstica mayor, polimedicación, número de días desde el alta, presencia de hipertensión y/o diabetes. Se evaluó el cumplimiento terapéutico y la dificultad en la administración de medicación mediante el test de Morisky-Green y el test de Haynes-Sackett, respectivamente. Se realizó un análisis descriptivo de las variables y se relacionaron estas con la adherencia terapéutica. Las variables con significación estadística se incluyeron en un modelo de regresión logística multivariante. Resultados: El 57% de los pacientes presentaron falta de adherencia al tratamiento farmacológico. El 23% presentaba dificultad en la administración de la medicación. Un 86% presentaba comorbilidades (hipertensión y/o diabetes) y el 79% tenía cuidador. El 86% de los pacientes estaban polimedicados (≥ 5 fármacos). Existe relación entre la falta de adherencia y la dificultad en la administración de los medicamentos (p = 0,021), la polimedicación (p = 0,002) y la presencia de diabetes mellitus (p=0,018). Conclusiones: La polimedicación, la presencia de diabetes mellitus y la existencia de dificultad en la administración de la medicación se evidencian como factores pronósticos de la falta de adherencia al tratamiento en pacientes mayores de 65 años

Objective: To analyse the rate of therapeutic nonadherence in patients who experience early readmissions, and identify the factors associated with nonadherence. Methods: An observational descriptive 3-month study (March-May 2014), which included all patients more than 65 years who were readmitted between 3 to 30 days following the last hospital discharge. Exclusion criteria: programmed re-admissions and readmissions to the Intensive Care Unit. Variables included in the study: age, sex, medical service, major diagnostic category, polypharmacy, number of days since the last hospital discharge, and hypertension and diabetes. Therapeutic adherence and difficulty in taking medication were assessed using the Morisky-Green test and the Haynes-Sackett test, respectively. A descriptive analysis of the variables was conducted, showing they were associated with therapeutic adherence. Statistically significant variables were included in a multivariate logistic regression model. Results: In total, 57% of the patients were nonadherent to pharmacological treatment; 23% had difficulty taking their medication; 86% had comorbidities (hypertension and diabetes); 79% had a caregiver; and 86% were polymedicated (≥ 5 medications). There was an association between lack of adherence and difficulty in taking medications (P = 0.021), polypharmacy (P = 0.002), and diabetes mellitus (P = 0.018). Conclusions: Polymedication, diabetes mellitus, and difficulty in taking medication were shown to be prognostic factors of lack of adherence to treatment in patients more than 65 years

Treatment adherence in patients older than 65 years who suffer early readmissions.

OBJECTIVE: Analyze the frequency of therapeutic noncompliance in patients who  suffer early readmissions, and identify the factors associated with it. METHOD: Observational, descriptive study of three months duration (March -  May 2014). All patients older than 65 years who readmitted in the 3-30 days  following the last hospital discharge were included. We excluded programmed  re-admissions and readmissions in the Intensive Care Unit. The variables  collected were: age, sex, medical service, major diagnostic category,  polypharmacy, number of days since the last hospital discharge, presence of  hypertension and/or diabetes. The therapeutic compliance and the difficulty in  the administration of medication were evaluated by means of the Morisky-Green  test and the Haynes-Sackett test respectively. A descriptive analysis of the  variables was carried out and they were related to the therapeutic adherence.  The variables with statistical significance were included in a multivariate logistic  regression model. RESULTS: Fifty seven percent of the patients presented lack of adherence to  pharmacological treatment. Twenty three percent had difficulty administering the medication. Eighty six percent had comorbidities  (hypertension and/or diabetes) and 79% had a caregiver. Eighty six percent of patients were polymedicated (≥ 5 drugs). There is a relationship between lack of adherence and difficulty in the administration of medications (p=0.021),  polypharmacy (p=0.002), and the presence of diabetes mellitus (p=0.018). CONCLUSIONS: Polymedication, the presence of diabetes mellitus and the existence of difficulty in the administration of medication are evidenced as prognostic factors of the lack of adherence to treatment in patients older than 65 years.

Objetivo: Analizar la frecuencia del incumplimiento terapéutico en pacientes que sufren reingresos hospitalarios precoces e identificar los factores asociados  al mismo.Método: Estudio observacional descriptivo de tres meses de duración (marzo­ mayo de 2014). Se incluyeron todos los pacientes mayores de 65 años que  reingresaron en los 3-30 días siguientes al alta hospitalaria. Fueron excluidos los reingresos programados y los reingresos en la Unidad de Cuidados Intensivos.  Las variables recogidas fueron: edad, sexo, servicio médico, categoría  diagnóstica mayor, polimedicación, número de días desde el alta, presencia de  hipertensión y/o diabetes. Se evaluó el cumplimiento terapéutico y la dificultad  en la administración de medicación mediante el test de Morisky-Green y el test  de Haynes-Sackett, respectivamente. Se realizó un análisis descriptivo de las  variables y se relacionaron estas con la adherencia terapéutica. Las variables  con significación estadística se incluyeron en un modelo de regresión logística multivariante.Resultados: El 57% de los pacientes presentaron falta de adherencia al tratamiento farmacológico. El 23% presentaba dificultad en la administración de la medicación. Un 86% presentaba comorbilidades  hipertensión y/o diabetes) y el 79% tenía cuidador. El 86% de los pacientes  estaban polimedicados (≥ 5 fármacos). Existe relación entre la falta de  adherencia y la dificultad en la administración de los medicamentos (p = 0,021), la polimedicación (p = 0,002) y la presencia de diabetes mellitus (p = 0,018).Conclusiones: La polimedicación, la presencia de diabetes mellitus y la  existencia de dificultad en la administración de la medicación se evidencian como factores pronósticos de la falta de adherencia al tratamiento en pacientes  mayores de 65 años.

Epigenetic control of influenza virus: role of H3K79 methylation in interferon-induced antiviral response.

Influenza virus stablishes a network of virus-host functional interactions, which depends on chromatin dynamic and therefore on epigenetic modifications. Using an unbiased search, we analyzed the epigenetic changes at DNA methylation and post-translational histone modification levels induced by the infection. DNA methylation was unaltered, while we found a general decrease on histone acetylation, which correlates with transcriptional inactivation and may cooperate with the impairment of cellular transcription that causes influenza virus infection. A particular increase in H3K79 methylation was observed and the use of an inhibitor of the specific H3K79 methylase, Dot1L enzyme, or its silencing, increased influenza virus replication. The antiviral response was reduced in conditions of Dot1L downregulation, since decreased nuclear translocation of NF-kB complex, and IFN-ß, Mx1 and ISG56 expression was detected. The data suggested a control of antiviral signaling by methylation of H3K79 and consequently, influenza virus replication was unaffected in IFN pathway-compromised, Dot1L-inhibited cells. H3K79 methylation also controlled replication of another potent interferon-inducing virus such as vesicular stomatitis virus, but did not modify amplification of respiratory syncytial virus that poorly induces interferon signaling. Epigenetic methylation of H3K79 might have an important role in controlling interferon-induced signaling against viral pathogens.

Reduced accumulation of defective viral genomes contributes to severe outcome in influenza virus infected patients.

Influenza A virus (IAV) infection can be severe or even lethal in toddlers, the elderly and patients with certain medical conditions. Infection of apparently healthy individuals nonetheless accounts for many severe disease cases and deaths, suggesting that viruses with increased pathogenicity co-circulate with pandemic or epidemic viruses. Looking for potential virulence factors, we have identified a polymerase PA D529N mutation detected in a fatal IAV case, whose introduction into two different recombinant virus backbones, led to reduced defective viral genomes (DVGs) production. This mutation conferred low induction of antiviral response in infected cells and increased pathogenesis in mice. To analyze the association between low DVGs production and pathogenesis in humans, we performed a genomic analysis of viruses isolated from a cohort of previously healthy individuals who suffered highly severe IAV infection requiring admission to Intensive Care Unit and patients with fatal outcome who additionally showed underlying medical conditions. These viruses were compared with those isolated from a cohort of mild IAV patients. Viruses with fewer DVGs accumulation were observed in patients with highly severe/fatal outcome than in those with mild disease, suggesting that low DVGs abundance constitutes a new virulence pathogenic marker in humans.

Quality indicators for technologies applied to the hospital pharmacy / Indicadores de calidad de tecnologías aplicadas a la farmacia hospitalaria

The TECNO group of the Sociedad Española de Farmacia Hospitalaria (Spanish Society of Hospital Pharmacy) has addressed the definition of a catalogue of indicators for performance, quality and safety in the use of technologies applied to the logistic activity of Hospital Pharmacy Units. The project was developed with a methodology of qualitative techniques by consensus, with the members of the TECNO Group participating as experts. Once indicators had been defined, a validation phase was conducted, and standards were established based on the result of the sampling carried out in the hospitals of the group members. A total of 28 indicators were obtained, with their corresponding quality standards applied to the use of technologies in the processed for medication storage, dispensing and preparation. The definition of quality indicators and their standards for measuring technologies in the use of medication represents a step forward in the improvement of their safety (AU)

El grupo TECNO de la Sociedad Española de Farmacia Hospitalaria ha abordado la definición de un catálogo de indicadores de funcionamiento, calidad y seguridad del uso de tecnologías aplicadas a la actividad logística de los Servicios de Farmacia Hospitalaria. El proyecto se desarrolló con una metodología de técnicas cualitativas de consenso participando como expertos los miembros del grupo TECNO. Una vez definidos los indicadores, se realizó una fase de validación y se establecieron estándares en base al resultado del muestreo realizado en los hospitales de los miembros del grupo. Se han obtenido un total de 28 indicadores con sus correspondientes estándares de calidad aplicados a la utilización de tecnologías en los procesos de almacenamiento, dispensación y elaboración de medicamentos. La definición de los indicadores de calidad y los estándares de medida de las tecnologías en el uso de los medicamentos es un paso adelante para mejorar su seguridad (AU)

Quality indicators for technologies applied to the hospital pharmacy.

The TECNO group of the Sociedad Española de Farmacia Hospitalaria (Spanish Society of Hospital Pharmacy) has addressed the definition of a catalogue of indicators for performance, quality and safety in the use of technologies applied to the logistic activity of Hospital Pharmacy Units.The project was developed with a methodology of qualitative techniques by consensus, with the members of the TECNO Group participating as experts. Once indicators had been defined, a validation phase was conducted, and standards were established based on the result of the sampling carried out in the hospitals of the group members.A total of 28 indicators were obtained, with their corresponding quality standards applied to the use of technologies in the processed for medication storage, dispensing and preparation.The definition of quality indicators and their standards for measuring technologies in the use of medication represents a step forward in the improvement of their safety.

El grupo TECNO de la Sociedad Española de Farmacia Hospitalaria ha abordado la definición de un catálogo de indicadores de funcionamiento, calidad y seguridad del uso de tecnologías aplicadas a la actividad logística de los Servicios de Farmacia Hospitalaria.El proyecto se desarrolló con una metodología de técnicas cualitativas de consenso participando como expertos los miembros del grupo TECNO. Una vez definidos los indicadores, se realizó una fase de validación y se establecieron estándares en base al resultado del muestreo realizado en los hospitales de los miembros del grupo.Se han obtenido un total de 28 indicadores con sus correspondientes estándares de calidad aplicados a la utilización de tecnologías en los procesos de almacenamiento, dispensación y elaboración de medicamentos.La definición de los indicadores de calidad y los estándares de medida de las tecnologías en el uso de los medicamentos es un paso adelante para mejorar su seguridad.

Corrigendum: Identification of Rare PB2-D701N Mutation from a Patient with Severe Influenza: Contribution of the PB2-D701N Mutation to the Pathogenicity of Human Influenza.

[This corrects the article on p. 575 in vol. 8, PMID: 28421062.].

Identification of Rare PB2-D701N Mutation from a Patient with Severe Influenza: Contribution of the PB2-D701N Mutation to the Pathogenicity of Human Influenza.

Several amino acid changes have been previously implicated in adaptation of avian influenza viruses to human hosts, among them the D701N change in the PB2 polymerase subunit that also is the main determinant of avian virus pathogenesis in animal models. However, previous studies using recombinant viruses did not provide conclusive information of the contribution of this PB2 residue to pathogenicity in human influenza virus strains. We identified this mutation in an A(H1N1)pdm09-like human influenza virus isolated from an infected patient with pneumonia and acute respiratory failure, admitted to the intensive care unit. An exhaustive search has revealed PB2-D701 as a highly conserved position in all available H1N1 human virus sequences in NCBI database, showing a very low prevalence of PB2-D701N change. Presence of PB2-701N amino acid correlates with severe or fatal outcome in those scarce cases with known disease outcome of the infection. In these patients, the residue PB2-701N may contribute to pathogenicity as it was previously reported in humans infected with avian viruses. This study helps to clarify a debate that has arisen regarding the role of PB2-D701N in human influenza virus pathogenicity.

Apoptosis, Toll-like, RIG-I-like and NOD-like Receptors Are Pathways Jointly Induced by Diverse Respiratory Bacterial and Viral Pathogens.

Lower respiratory tract infections are among the top five leading causes of human death. Fighting these infections is therefore a world health priority. Searching for induced alterations in host gene expression shared by several relevant respiratory pathogens represents an alternative to identify new targets for wide-range host-oriented therapeutics. With this aim, alveolar macrophages were independently infected with three unrelated bacterial (Streptococcus pneumoniae, Klebsiella pneumoniae, and Staphylococcus aureus) and two dissimilar viral (respiratory syncytial virus and influenza A virus) respiratory pathogens, all of them highly relevant for human health. Cells were also activated with bacterial lipopolysaccharide (LPS) as a prototypical pathogen-associated molecular pattern. Patterns of differentially expressed cellular genes shared by the indicated pathogens were searched by microarray analysis. Most of the commonly up-regulated host genes were related to the innate immune response and/or apoptosis, with Toll-like, RIG-I-like and NOD-like receptors among the top 10 signaling pathways with over-expressed genes. These results identify new potential broad-spectrum targets to fight the important human infections caused by the bacteria and viruses studied here.

Potential drug-drug interactions in hospitalised haematological patients.

Background Frequently, haematological patients undergo highly complex and intensive treatment protocols, so a high risk of drug-drug interactions could be expected. Objectives To determine prevalence of clinically relevant drug-drug interactions, to identify the most frequent drug-drug interactions and associated risk factors. Methods A prospective, observational and descriptive study was carried out from November 2012 to February 2013. Twice a week, every patient's treatment sheet was collected. Each medication list was screened through two databases: Thomson MicromedexTM and Drug Interaction FactsTM. All identified potential drug-drug interactions with a moderate or higher severity rating were recorded. Summary statistics were used to describe patient and disease characteristics, most often prescribed drugs, and frequency, types and classification of drug-drug interactions. Multiple logistic regression models were used to identify risk factors associated with drug-drug interactions. Results A total of 2061 drug-drug interactions were detected in 317 treatment sheets from 58 patients. The prevalence of treatment sheets with drug-drug interactions by Micromedex and Drug Interaction Facts databases were 74.1% and 56.8%, respectively. Azole antifungals, immunosuppressive drugs, antiemetics, antidepressants, acid suppressants and corticosteroids were the most frequent involved drugs. In multivariate analysis, the main risk factor associated with increased odds for drug-drug interactions was a higher number of non-antineoplastic drugs. Conclusions The prevalence of drug-drug interactions was common, with immunosuppressant and azole antifungal agents being the most commonly involved drugs. The factor having the greatest influence on drug-drug interactions was a higher number of non-antineoplastic drugs.

Correction: ISG15 Regulates Peritoneal Macrophages Functionality against Viral Infection.

[This corrects the article DOI: 10.1371/journal.ppat.1003632.].

Inhibition of Influenza Virus Replication by DNA Aptamers Targeting a Cellular Component of Translation Initiation.

The genetic diversity of the influenza virus hinders the use of broad spectrum antiviral drugs and favors the appearance of resistant strains. Single-stranded DNA aptamers represent an innovative approach with potential application as antiviral compounds. The mRNAs of influenza virus possess a 5'cap structure and a 3'poly(A) tail that makes them structurally indistinguishable from cellular mRNAs. However, selective translation of viral mRNAs occurs in infected cells through a discriminatory mechanism, whereby viral polymerase and NS1 interact with components of the translation initiation complex, such as the eIF4GI and PABP1 proteins. We have studied the potential of two specific aptamers that recognize PABP1 (ApPABP7 and ApPABP11) to act as anti-influenza drugs. Both aptamers reduce viral genome expression and the production of infective influenza virus particles. The interaction of viral polymerase with the eIF4GI translation initiation factor is hindered by transfection of infected cells with both PABP1 aptamers, and ApPABP11 also inhibits the association of NS1 with PABP1 and eIF4GI. These results indicate that aptamers targeting the host factors that interact with viral proteins may potentially have a broad therapeutic spectrum, reducing the appearance of escape mutants and resistant subtypes.

hCLE/C14orf166, a cellular protein required for viral replication, is incorporated into influenza virus particles.

The influenza A virus polymerase associates with a number of cellular transcription-related factors, including the RNA polymerase II (RNAP II). We previously described that the cellular protein hCLE/C14orf166 interacts with and stimulates influenza virus polymerase as well as RNAP II activities. Here we show that, despite the considerable cellular shut-off observed in infected cells, which includes RNAP II degradation, hCLE protein levels increase throughout infection in a virus replication-dependent manner. Human and avian influenza viruses of various subtypes increase hCLE levels, but other RNA or DNA viruses do not. hCLE colocalises and interacts with viral ribonucleoproteins (vRNP) in the nucleus, as well as in the cytoplasm late in infection. Furthermore, biochemical analysis of purified virus particles and immunoelectron microscopy of infected cells show hCLE in virions, in close association with viral vRNP. These findings indicate that hCLE, a cellular protein important for viral replication, is one of the very few examples of transcription factors that are incorporated into particles of an RNA-containing virus.