Nicotinamide activates latent HIV-1 ex vivo in ART suppressed individuals, revealing higher potency than the association of two methyltransferase inhibitors, chaetocin and BIX01294

ABSTRACT Background: Latent HIV-1 is a major hurdle in obtaining HIV-1 sustained virological remission (SVR). Here we explored histone deacetylation inhibition property of nicotinamide (NAM; n = 17) for the first time in comparison to a combination of methyltransferase inhibitors (MTIs; Chaetocin and BIX01294; n = 25) to reactivate latent HIV ex vivo in CD8-depleted PBMCs from antiretroviral treated aviremic individuals. Results: NAM reactivated HIV-1 from 13/17 (76.4%) samples compared to 20/25 (80.0%) using MTIs with mean viral load (VLs) of 4.32 and 3.22 log10 RNA copies/mL, respectively (p = 0.004). Mean purging time after NAM and MTIs stimulation was 5.1 and 6.75 days, respectively (p = 0.73). Viral purging in autologous cultures exhibited blunted HIV recovery with fluctuating VLs followed by a complete viral extinction when expanded in allogenic system. Electron microscopy from five supernatants revealed anomalous viral particles, with lack of complete viral genomes when characterized by ultradeep sequencing through metagenomics approach (n = 4). Conclusion: NAM alone was more potent HIV-1 activator than combination of MTIs, with potential of clinical use.

Dengue virus infection induces chromatin remodeling at locus AAEL006536 in the midgut of Aedes aegypti / La infección por virus dengue induce remodelación de la cromatina en el locus AAEL006536 en el intestino medio de Aedes aegypti

Abstract: Objective: To identify and characterize Aedes aegypti's AAEL006536 gene proximal upstream cis-regulatory sequences activated by dengue virus infection. Materials and methods: A. aegypti Rockefeller strain mosquitoes were blood fed or infected with dengue virus 2. Open chromatin profiling was then carried out in pools of midguts from each group of mosquitoes. Results: The proximal upstream region does not contain open chromatin sites in the midguts of blood-fed mosquitoes as detected by FAIRE-qPCR. In contrast, two cis-regulatory sites were identified in the same upstream region of dengue virus-infected mosquito midguts. The distal sequence contains STAT-, REL- and C/EBP-type transcription factor binding sites. Conclusion: The activation of two proximal cis-regulatory sequences, induced by dengue virus infection, is mediated by chromatin remodeling mechanisms. Binding sites suggest a dengue virus infection-induced participation of immunity transcription factors in the up-regulation of this gene. This suggests the participation of the AAEL006536 gene in the mosquito's antiviral innate immune response.

Resumen: Objetivo: Identificar y caracterizar las secuencias reguladoras activadas por la infección por virus dengue en la región proximal del gen AAEL006536 de Aedes aegypti. Material y métodos: Mosquitos de la cepa Rockefeller de A. aegypti se infectaron con virus dengue o se alimentaron con sangre. Se obtuvieron los perfiles de cromatina abierta del locus en los intestinos de cada uno de los grupos. Resultados: Se identificaron dos sitios reguladores solo en los intestinos de mosquitos infectados por virus dengue. El sitio distal contiene sitios de unión a factores de transcripción tipo REL, STAT y C/EBP. Conclusiones: La activación de dos sitios reguladores proximales está mediada por la remodelación de la cromatina. Los sitios de unión a factores de transcripción en el sitio regulador distal sugieren la participación de las vías de inmunidad en la regulación del gen. Esto sugiere la participación de este gen en la respuesta inmune del mosquito frente a la infección viral.

Regulation of HPV transcription

Human papillomavirus infection is associated with the development of malignant and benign neoplasms. Approximately 40 viral types can infect the anogenital mucosa and are categorized into high- and low-risk oncogenic human papillomavirus, depending on their association with the development of cervical carcinoma. High-risk human papillomavirus 16 and 18 are detected in 55% and 15% of all invasive cervical squamous cell carcinomas worldwide, respectively. Low-risk human papillomavirus 6 and 11 are responsible for 90% of genital warts and are also associated with the development of recurrent respiratory papillomatosis. Human papillomavirus preferentially infects mitotic active cells of the basal layer from both mucosal and cutaneous epithelium through microabrasions. The viral life cycle synchronizes with the epithelial differentiation program, which may be due, in part, to the binding of differentially expressed cellular transcription factors to the long control region throughout the various epithelial layers. This review aimed to summarize the current knowledge regarding the mechanisms by which viral gene expression is regulated and the influence of human papillomavirus heterogeneity upon this phenomenon. A better understanding of the regulatory mechanisms may elucidate the particularities of human papillomavirus-associated pathogenesis and may provide new tools for antiviral therapy.

Serum microRNA-30c levels are correlated with disease progression in Xinjiang Uygur patients with chronic hepatitis B

We aimed to investigate the potential role and mechanism of microRNA-30c (miR-30c) in the pathological development of chronic hepatitis B (CHB). The serum levels of miR-30c in hepatitis B virus (HBV) carrier Xinjiang Uygur patients with inactive, low-replicative, high-replicative and HBe antigen-positive CHB were investigated. HepG2 cells were co-transfected with pHBV1.3 and miR-30c mimic or inhibitor or scramble RNA. The effects of miR-30c dysregulation on HBV replication and gene expression, cell proliferation and cell cycle were then investigated. miR-30c was down-regulated in Xinjiang Uygur patients with CHB compared to healthy controls and its expression level discriminated HBV carrier patients with inactive, low-replicative, high-replicative and HBe antigen-positive risk for disease progression. Overexpression of miR-30c significantly inhibited HBV replication and the expressions of HBV pgRNA, capsid-associated virus DNA and Hbx in hepatoma cells. Moreover, overexpression of miR-30c significantly inhibited cell proliferation and delayed G1/S phase transition in hepatoma cells. Opposite effects were obtained after suppression of miR-30c. Our results indicate that miR-30c was down-regulated in Xinjiang Uygur patients with CHB, and miR-30c levels could serve as a marker for risk stratification of HBV infection. Down-regulation of miR-30c may result in the progression of CHB via promoting HBV replication and cell proliferation.

Contribution of 3CD Region to the Virulence of Enterovirus 71 / 生物医学与环境科学（英文）

Enterovirus 71 is a neuroinvasive virus that is associated with severe neurological complications. We had earlier suggested that the replication capacity of a severe strain was higher than that of a mild strain. The recombinant 3CRV and 3CDRV virus strains were successfully rescued in our previous study. In the present study, we found no difference in virulence between 3CRV and severe strains. However, the capacity of replication and to cause cell injury of 3CDRV strain decreased in vitro, especially at 39.5 °C. Replacement of 3CD region in the severe strain led to milder symptoms, less body weight loss, and lower viral load in ICR mice. Histopathological findings indicated less severe injury in mice infected with 3CDRV strain. This study suggests that the 3CD region contributes to the attenuation of the severe strain, including its replication capacity and temperature sensitivity.

Solubility as a limiting factor for expression of hepatitis A virus proteins in insect cell-baculovirus system

The use of recombinant proteins may represent an alternative model to inactivated vaccines against hepatitis A virus (HAV). The present study aimed to express the VP1 protein of HAV in baculovirus expression vector system (BEVS). The VP1 was expressed intracellularly with molecular mass of 35 kDa. The VP1 was detected both in the soluble fraction and in the insoluble fraction of the lysate. The extracellular expression of VP1 was also attempted, but the protein remained inside the cell. To verify if hydrophobic characteristics would also be present in the HAV structural polyprotein, the expression of P1-2A protein was evaluated. The P1-2A polyprotein remained insoluble in the cellular extract, even in the early infection stages. These results suggest that HAV structural proteins are prone to form insoluble aggregates. The low solubility represents a drawback for production of large amounts of HAV proteins in BEVS.

Receptor expression and responsiveness of human peripheral blood mononuclear cells to a human cytomegalovirus encoded CC chemokine

Human cytomegalovirus is a ubiquitous pathogen that infects the majority of the world's population. After long period of time co-evolving with human being, this pathogen has developed several strategies to evade host immune surveillance. One of the major trick is encoding homologous to those of the host organism or stealing host cellular genes that have significant functions in immune system. To date, we have found several viral immune analogous which include G protein coupled receptor, class I major histocompatibility complex and chemokine. Chemokine is a small group of molecules which is defined by the presence of four cysteines in highly conserved region. The four kinds of chemokines (C, CC, CXC, and CX3C) are classified based on the arrangement of 1 or 2 N-terminal cysteine residues. UL128 protein is one of the analogous that encoded by human cytomegalovirus that has similar amino acid sequences to the human CC chemokine. It has been proved to be one of the essential particles that involved in human cytomegalovirus entry into epithelial/endothelial cells as well as macrophages. It is also the target of potent neutralizing antibodies in human cytomegalovirus-seropositive individuals. We had demonstrated the chemotactic trait of UL128 protein in our previous study. Recombinant UL128 in vitrohas the ability to attract monocytes to the infection region and enhances peripheral blood mononuclear cell proliferation by activating the MAPK/ERK signaling pathway. However, the way that this viral encoded chemokine interacting with peripheral blood mononuclear cells and the detailed mechanism that involving the virus entry into host cells keeps unknown. Here we performed in vitroinvestigation into the effects of UL128 protein on peripheral blood mononuclear cell's activation and receptor binding, which may help us further understand the immunomodulatory function of UL128 protein as well as human cytomegalovirus diffusion mechanism.

Studies published in indexed journals on lawsuits for medicines in Brazil: a systematic review / Estudios publicados en revistas indexadas acerca de decisiones judiciales para el acceso a los medicamentos en Brasil: una revisión sistemática / Estudos publicados em periódicos indexados sobre decisões judiciais para acesso a medicamentos no Brasil: uma revisão sistemática

The aim of this systematic review was to identify and characterize articles in indexed scientific journals with quantitative data surveys on administrative or legal proceedings for access to medicines. The SciELO, LILACS, MEDLINE via PubMed, Embase, and Scopus databases were used. We identified 45 articles, of which 17 were selected. The larger studies, each covering between 2,000 and 2,927 lawsuits, were done in the states of São Paulo, Rio de Janeiro, and Santa Catarina, Brazil. Eleven studies specified the type of legal representation, of which six examined cases with public attorneys and five with private attorneys. Only two studies reported whether the lawsuit was individual or class action, and in both the claims were individual. Since the majority of the medicines requested in the lawsuits were medium to high-cost, the review indicates that lawsuits contributed to the incorporation of these drugs into current pharmaceutical care in Brazil.

El objetivo de esta revisión sistemática fue identificar y caracterizar los artículos disponibles en revistas científicas indexadas en bases de datos electrónicas, que llevaron a cabo un estudio cuantitativo de datos, procedimientos administrativos o judiciales sobre la cuestión del acceso a los medicamentos a través de demandas judiciales. Los estudios fueron localizados en las bases de datos SciELO, LILACS, MEDLINE vía PubMed, Embase, Scopus. Se identificaron 45 artículos, de los cuales se seleccionaron 17. Los estudios que se llevaron a cabo engloban de 2.000 a 2.927 procesos judiciales en São Paulo, Río de Janeiro y Santa Catarina, Brasil. En once estudios se realizaron encuestas a los representantes legales de la acción judicial. En seis estudios predominó la representación pública legal y en cinco abogados privados. Sólo dos estudios examinaron si la acción era individual o colectiva y en los dos hubo prevalencia de acciones individuales. Como la mayoría de los medicamentos estaba involucrada en acciones legales de medio y alto coste, se cree que las demandas han contribuido a la incorporación de fármacos en la política pública actual.

O objetivo desta revisão sistemática foi identificar e caracterizar artigos disponíveis em periódicos científicos indexados em bases eletrônicas, que realizaram levantamento de dados quantitativo, em processos administrativos ou judiciais, sobre a questão do acesso a medicamentos por meio de ações judiciais. Foram usadas as bases de dados SciELO, LILACS, MEDLINE via PubMed, Embase e Scopus. Identificamos 45 artigos, dos quais foram selecionados 17 artigos. Os estudos com faixa de 2.000 a 2.927 processos foram conduzidos em São Paulo, Rio de Janeiro e Santa Catarina, Brasil. Em 11 estudos foram pesquisadas qual a representação jurídica da ação. Em seis estudos predominaram a representação de advogados públicos e em cinco particulares. Somente dois estudos observaram se a ação era coletiva ou individual, sendo que nas duas pesquisas a prevalência era de ações individuais. Como a maioria dos medicamentos envolvidos nas ações é de médio e alto custo, acredita-se que as demandas judiciais tenham contribuído para incorporação de medicamentos nas ações de assistência farmacêutica atuais.

Epilepsy-induced electrocardiographic alterations following cardiac ischemia and reperfusion in rats

The present study evaluated electrocardiographic alterations in rats with epilepsy submitted to an acute myocardial infarction (AMI) model induced by cardiac ischemia and reperfusion. Rats were randomly divided into two groups: control (n=12) and epilepsy (n=14). It was found that rats with epilepsy presented a significant reduction in atrioventricular block incidence following the ischemia and reperfusion procedure. In addition, significant alterations were observed in electrocardiogram intervals during the stabilization, ischemia, and reperfusion periods of rats with epilepsy compared to control rats. It was noted that rats with epilepsy presented a significant increase in the QRS interval during the stabilization period in relation to control rats (P<0.01). During the ischemia period, there was an increase in the QRS interval (P<0.05) and a reduction in the P wave and QT intervals (P<0.05 for both) in rats with epilepsy compared to control rats. During the reperfusion period, a significant reduction in the QT interval (P<0.01) was verified in the epilepsy group in relation to the control group. Our results indicate that rats submitted to an epilepsy model induced by pilocarpine presented electrical conductivity alterations of cardiac tissue, mainly during an AMI episode.

Genomic assays for Epstein-Barr virus-positive gastric adenocarcinoma

A small set of gastric adenocarcinomas (9%) harbor Epstein-Barr virus (EBV) DNA within malignant cells, and the virus is not an innocent bystander but rather is intimately linked to pathogenesis and tumor maintenance. Evidence comes from unique genomic features of host DNA, mRNA, microRNA and CpG methylation profiles as revealed by recent comprehensive genomic analysis by The Cancer Genome Atlas Network. Their data show that gastric cancer is not one disease but rather comprises four major classes: EBV-positive, microsatellite instability (MSI), genomically stable and chromosome instability. The EBV-positive class has even more marked CpG methylation than does the MSI class, and viral cancers have a unique pattern of methylation linked to the downregulation of CDKN2A (p16) but not MLH1. EBV-positive cancers often have mutated PIK3CA and ARID1A and an amplified 9p24.1 locus linked to overexpression of JAK2, CD274 (PD-L1) and PDCD1LG2 (PD-L2). Multiple noncoding viral RNAs are highly expressed. Patients who fail standard therapy may qualify for enrollment in clinical trials targeting cancer-related human gene pathways or promoting destruction of infected cells through lytic induction of EBV genes. Genomic tests such as the GastroGenus Gastric Cancer Classifier are available to identify actionable variants in formalin-fixed cancer tissue of affected patients.

Hepatitis B virus replication and viral gene expressions do not affect CDC37 level in hepatocytes in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the influence of hepatitis B virus (HBV) replication and expressions of different viral genes on CDC37 level in hepatocytes.</p><p><b>METHODS</b>We amplified and cloned 6 HBV genes (P, preS1, preS2, S, C and X) into pCMV expression vectors, which were transfected in Huh7 and HepG2 hepatoma cell lines, and CDC37 expression level in the cells was detected using Western blotting. Wealso cloned the promoter sequence of CDC37 into pGL3 vector, and co-transfected pGL3 with pCMV recombinant plasmids into Huh7 and HepG2 cells and the fluorescent signals were detected. To study the influence of HBV replication on CDC37 expression, we constructed 1.28-copy overlength genomes of HBV genotypes B, C, D and CD recombinant. The overlength HBV genomes were transformed into Adeasier-1 cells for recombination and into 293 cells for packaging. Huh7 and HepG2 cell lines infected with the packaged HBV recombinant adenoviruses were examined for CDC37 expression with Western blotting.</p><p><b>RESULTS</b>Western blotting showed that the expression of different HBV genes did not obviously affect the protein level of CDC37 in the hepatocytes. The protein expression of HBV genes had no effect on the activity of CDC37 promoter. Huh7 and HepG2 cells infected with 1.28-copy HBV replicon showed no significant changes in the expression level of CDC37.</p><p><b>CONCLUSION</b>HBV replication and its gene expression have no effect on the level of CDC37 in hepatocytes in vitro.</p>

Effects of HIV-1 tat on secretion of TNF-α and IL-1β by U87 cells in AIDS patients with or without AIDS dementia complex / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis.</p><p><b>METHODS</b>HIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFP/tat. The MSCV-IRES-GFP/tat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA.</p><p><b>RESULTS</b>HIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area (38-47aa). All Tat proteins could induce U87 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen. The level of Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen were obviously higher than that from the non-ADC patient's basal ganglia.</p><p><b>CONCLUSION</b>Tat protein core functional area (38-47aa) may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.</p>

New Strategy for anti-HBV therapy: blocking P-8 interaction / 病毒学报

Clinically being applied treatment against chronic hepatitis has three limitations: low response rates, severe adverse effects and a high rate of drug resistance. Hence, novel targets for antiviral therapy need to be developed so as to provide an armory of different strategies. During the replication of hepatitis B virus, the interaction of viral polymerase (P protein, also called P) and epsilonRNA is indispensable for the initiation of reverse transcription via protein priming and the pregenome RNA (pgRNA) packaging. Three strategies are currently developed for blocking P-epsilon interaction: heat shock protein inhibitors, epsilonaptamers and chemical compounds for blocking formation of P-epsilon complex. Previously, our group has for the first time worldwide in vitro screened several aptamers, which are able to interfere with the P-epsilon interaction. A strong inhibition against HBV was observed in vitro and in vivo experiments, respectively. In conclusion, the so far developed chemicals suppressing the P-epsilon interaction may bypass or overcome the viral resistance problems during clinic treatment and represent a highly attractive option for therapeutic intervention.

Novel cationic liposome loading siRNA inhibits the expression of hepatitis B virus HBx gene / 药学学报

In order to solve the problem of selection and in vivo delivery problem in siRNA treatment, hepatitis B virus (HBV) HBx gene which could be targeted by siRNA was studied. The siRNA expression plasmid which specific inhibits HBx expression was obtained by in vitro selection via a dual-luciferase plasmid including HBx-Fluc fusion protein expression domain. The selected siRNA expression plasmid was then encapsulated in PEG-modified cationic liposome, which was devoted into pharmacodynamic studies at both cellular and animal level. The results illustrated that the cationic liposome which encapsulated siRNA expression plasmid could effectively inhibit HBx gene expression both in vitro and in vivo.

Research progress in roles of high-risk human papillomavirus E2 protein / 病毒学报

High-risk human papillomavirus (HPV) is the principal cause of various cancers including cervical cancer, anal cancer, vulvar cancer, and some head and neck cancers. In the viral life cycle, by interacting with both viral and host DNA and proteins, the HPV E2 protein plays a pivotal role in viral transcriptional regulation and DNA replication, and it is also associated with modification of various cellular processes, including host gene transcription, RNA processing, apoptosis, ubiquitination, and intracellular trafficking, to create a convenient environment for a replicative cycle of the virus and contribute to the HPV pathogenesis. Elucidating the roles of E2 protein throughout the viral life cycle will improve our understanding of the viral life cycle and pathogenesis and help us identify novel antiviral agents with therapeutic potential. This article reviews the research progress in the structure, roles, and activity of high-risk HPV E2 protein, particularly that of HPV-16.

Effects of bm47 deletion on viral replication and transcription of Bombyx mori nucleopolyhedrovirus / 病毒学报

Bombyx mori nucleopolyhedrovirus (BmNPV) bm47 gene is found in all sequenced lepidopteran nucleopolyhedroviruses (NPVs). It is one of the core genes of NPVs. However, the role of bm47 in the biological cycle of NPV remains unknown. In this study, the Red recombination system was used to knock out bm47 from BmNPV to construct bm47-ko-Bacmid in E. coli BW25113 system. Then bm47 gene was introduced back to the viral genome using the Bac-to-Bac system to create the repair virus bm47-re-Bacmid. TCID50 assay and real-time PCR (qPCR) were used to evaluate the effects of bm47 deletion on viral DNA replication, gene transcription, and protein expression. qPCR results showed that bm47 knock-out had no significant effect on viral DNA replication. However, the qPCR results showed that bm47-ko-Bacmid significantly decreased the transcription levels of early gene lef-3, late gene vp39, and very late gene p10 at 48 h and 72 h after viral transfection of BmN cells (P < 0.05). This work will provide a foundation for further studies on the biological function of BmNPV bm47 in viral replication and transcription.

Factores que participan en la interacción huésped-agente patógeno en el riesgo de Linfoma de Hodgkin inducido por el virus Epstein Barr / Factors involved in host-pathogen interaction for the risk of Hodgkin lymphoma induced by Epstein Barr virus

El linfoma de Hodgkin (LH) es una neoplasia del sistema linfático. La incidencia mundial anual del LH es de 3-10/100,000 habitantes. El mecanismo mediante el cual se lleva a cabo la transformación celular no es completamente claro; sin embargo, algunas evidencias parecen indicar que ciertos virus oncogénicos como el virus Epstein Barr (VEB), pueden tener alto impacto en la patogénesis de la linfoproliferación. También algunos factores genéticos y ambientales pueden estar involucrados, pues se ha encontrado una alta incidencia de casos de LH entre individuos de una misma familia que comparten características genéticas y conviven en un mismo ambiente. En México se han realizado estudios encaminados a conocer la prevalencia del VEB en pacientes con LH y se ha encontrado la presencia de este virus hasta en el 64,2%. El VEB ha sido detectado en las Células Reed Sternberg (CRS) y en Células de Hodgkin (CH) en el 50% de los casos de LH clásico. No se ha dado hasta ahora una explicación satisfactoria, pero se ha propuesto que la variabilidad geográfica y la variabilidad inmunológica desempeñan un papel determinante en la positividad del VEB en LH. A pesar de los avances que hasta ahora se tienen, no existen suficientes evidencias que permitan establecer una clara asociación entre los factores del huésped, el medio ambiente y el agente patógeno en el riesgo de la linfoproliferación que conduce al desarrollo de LH. La presente revisión tiene como objetivo analizar algunos de los factores de riesgo que influyen durante la interacción huésped, agente patógeno y medio ambiente en la etiología del LH.

Hodgkin lymphoma (HL) is a neoplasm characterized by malignant cells called Reed Sternberg and Hodgkin’s cells in the lymphatic system. Such cells comprise 1% of the tumor while the remainder is made up of lymphocytes, histiocytes, eosinophils and plasma non-neoplastic cells. The annual global incidence of HL is 3-10/100,000 inhabitants and is most commonly found in young adults. The mechanism by which cell transformation is accomplished is not entirely clear; however, some evidences suggest that oncogenic viruses like the Epstein Barr virus (EBV) may have a high impact on the pathogenesis of lymphoproliferation. Genetic and environmental factors could be involved, since it has been found a high incidence of HL among members of the same family. In Mexico, there have been studies to determine the prevalence of EBV in patients with HL and found the presence of this virus in up to 64.2% of the cases. EBV has been detected in the Reed Sternberg cells and Hodgkin cells in 50% of cases of classical HL. There is not a satisfactory explanation for this, but it has been proposed that geographic and immunological variabilities play a role in the positivity of EBV in HL. However, despite recent advances in the field, there is insufficient evidence to show a clear association between host factors, environment and pathogens, and the risk of lymphoproliferation leading to the development of HL. This review aims to give an overview about the risk factors that influence the interaction of host, pathogens and environment in the etiology of HL.

The shift from low to high non-structural protein 1 expression in rotavirus-infected MA-104 cells

A hallmark of group/species A rotavirus (RVA) replication in MA-104 cells is the logarithmic increase in viral mRNAs that occurs four-12 h post-infection. Viral protein synthesis typically lags closely behind mRNA synthesis but continues after mRNA levels plateau. However, RVA non-structural protein 1 (NSP1) is present at very low levels throughout viral replication despite showing robust protein synthesis. NSP1 has the contrasting properties of being susceptible to proteasomal degradation, but being stabilised against proteasomal degradation by viral proteins and/or viral mRNAs. We aimed to determine the kinetics of the accumulation and intracellular distribution of NSP1 in MA-104 cells infected with rhesus rotavirus (RRV). NSP1 preferentially localises to the perinuclear region of the cytoplasm of infected cells, forming abundant granules that are heterogeneous in size. Late in infection, large NSP1 granules predominate, coincident with a shift from low to high NSP1 expression levels. Our results indicate that rotavirus NSP1 is a late viral protein in MA-104 cells infected with RRV, presumably as a result of altered protein turnover.

Cloning and expression analysis of multiple proteins encoding P gene of Newcastle disease virus.

Viral gene oncotherapy is emerging as a biotherapeutic cancer treatment modality based on targeted killing of cancer cells by viral genes. Newcastle disease virus (NDV) has the property to cause selective oncolysis of tumor cells sparing normal cells. NDV has a single stranded negative sense RNA genome, which is 15,186 nucleotide long and consists of six genes, which codes for eight proteins. NDV like other paramyxoviruses has the ability to generate multiple proteins from the P gene. P protein is encoded by an unedited transcript of the P gene, whereas the V and W protein are the results of RNA editing event in which one and two G residues are inserted at a conserved editing site within the P gene mRNA resulting in V and W transcripts, respectively. Although NDV is known to cause oncolysis by triggering apoptosis, the role of different viral proteins in selective oncolysis is still unclear. P gene edited products are known for its anti-apoptotic property in homologous host. In the present study, NDV P gene and its RNA edited products were amplified, cloned, sequenced and in vitro expression was done in HeLa cells. Further constructs were assayed for their apoptosis inducing ability in HeLa cells. Preliminary study suggested that P, V and W proteins are not apoptotic to HeLa cells.

Construction and immunogenicity of recombinant bacteriophage T7 vaccine expressing M2e peptides of avian influenza virus / 病毒学报

To construct a recombinant T7 phage expressing matrix protein 2 ectodomain (M2e) peptides of avian influenza A virus and test immunological and protective efficacy in the immunized SPF chickens. M2e gene sequence was obtained from Genbank and two copies of M2e gene were artificially synthesised, the M2e gene was then cloned into the T7 select 415-1b phage in the multiple cloning sites to construct the recombinant phage T7-M2e. The positive recombinant phage was identified by PCR and sequencing, and the expression of surface fusion protein was confirmed by SDS-PAGE and Western-blot. SPF chickens were subcutaneously injected with 1 X 10(10) pfu phage T7-M2e, sera samples were collected pre- and post-vaccination, and were tested for anti-M2e antibody by ELISA. The binding capacity of serum to virus was also examined by indirect immunofluorescence assay in virus- infected CEF. The immunized chickens were challenged with 200 EID50 of H9 type avian influenza virus and viral isolation rate was calculated to evaluate the immune protective efficacy. A recombinant T7 phage was obtained displaying M2e peptides of avian influenza A virus, and the fusion protein had favorable immunoreactivity. All chickens developed a certain amount of anti-M2e antibody which could specially bind to the viral particles. In addition, the protection efficacy of phage T7-M2e vaccine against H9 type avian influenza viruses was 4/5 (80%). These results indicate that the recombinant T7 phage displaying M2e peptides of avian influenza A virus has a great potential to be developed into a novel vaccine for the prevention of avian influenza infection.