Hepatitis C virus (HCV) infects approximately 170 million individuals worldwide. Prevention of HCV infection complications is based on antiviral therapy with the combination of pegylated interferon alfa and ribavirin....Hepatitis C virus (HCV) infects approximately 170 million individuals worldwide. Prevention of HCV infection complications is based on antiviral therapy with the combination of pegylated interferon alfa and ribavirin. The use of serological and virological tests has become essential in the management of HCV infection in order to diagnose infection, guide treatment decisions and assess the virological response to antiviral therapy. Anti- HCV antibody testing and HCV RNA testing are used to diagnose acute and chronic hepatitis C. The HCV genotype should be systematically determined before treatment, as it determines the indication, the duration of treatment, the dose of ribavirin and the virological monitoring procedure. HCV RNA monitoring during therapy is used to tailor treatment duration in HCV genotype 1 infection, and molecular assays are used to assess the end-of-treatment and, most importantly the sustained virological response, i.e. the endpoint of therapy.展开更多
The World Society for Virology(WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct rese...The World Society for Virology(WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct research of viruses that affect humans, other animals, plants, and other organisms. One of the objectives of WSV is to connect virologists worldwide and support collaboration. Fulfilling this objective, virologists from fourteen countries in North America,Europe, Africa, Asia, and the Middle East met on 25–27 th August 2019 in Stockholm, Sweden at the Karolinska University Hospital for the first Committee Meeting of WSV. This meeting included compelling keynote and honorary speeches and a series of 18 scientific talks were given encompassing a diverse array of subjects within virology. Followed by the scientific session, a business session was held where multiple aspects and next steps of the society were discussed and charted out.展开更多
BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinic...BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinical,and demographic characteristics of Omicron infections within the early outbreak cluster in western part of Sri Lanka.METHODS We analyzed sequence data from January 2022 to April 2022 to understand variant dynamics,clinical presentation,and demographic associations.RESULTS Whole-genome sequencing of 85 nasopharyngeal and throat swab samples collected in western part of Sri Lanka between January and April 2022 identified 70(82.34%)of it as Omicron variants.BA.2 was the most prevalent sub-lineage(57%),followed by BA.1.1(14.20%)and majority of them were from>12 years old individuals.Phylogenetic analysis revealed clustering into four distinct clades(21I,21K,21L,and 21M),suggesting potential differences in transmission chains or evolutionary pressures.CONCLUSION This study found BA.2 to be the predominant Omicron sub-lineage in the western part of Sri Lanka during the first quarter of 2022,aligning with global trends.Phylogenetic analysis revealed diverse introductions and local transmission.Continued genomic surveillance and robust public health measures remain crucial for managing the evolving SARS-CoV-2 landscape.展开更多
BACKGROUND Tenofovir alafenamide fumarate(TAF)is one of the first-line treatments used to treat chronic hepatitis B patients;TAF has strong antiviral activity and a high barrier to resistance.Although virological brea...BACKGROUND Tenofovir alafenamide fumarate(TAF)is one of the first-line treatments used to treat chronic hepatitis B patients;TAF has strong antiviral activity and a high barrier to resistance.Although virological breakthroughs in patients during TAF treatment are rare,patients with incomplete responses to TAF are occasionally observed.AIM To investigate responsible mutations in the reverse transcriptase region of hepatitis B virus(HBV)for TAF-incomplete responses.METHODS Thirteen chronic hepatitis B patients who received TAF monotherapy were included.A TAF-incomplete responder was defined as one who was continuously positive for HBV DNA over 2 years after TAF treatment initiation.The emergences of mutations in TAF-incomplete responders were evaluated before,one year after,and two years after treatment by deep sequencing of HBV DNA and RNA.RESULTS Two patients were continuously positive for HBV DNA over two years.The rtL269I mutation,one of the CYEI mutations linked to tenofovir resistance,was detected in both patients by direct sequencing.The deep sequencing analysis revealed that a combination of rtT118A and rtL220I mutations and the rtL269I mutation were predominantly detected in HBV DNA even when these mutations were barely detected in HBV RNA.This suggests a superior replication capability of the HBV variants with these mutations under TAF treatment.CONCLUSION The deep sequencing analysis of HBV DNA and RNA and comparing the detection rates of mutations were useful for estimating responsible mutations for TAF-incomplete responses.Such analysis is needed to evaluate the association between mutations that emerge during TAF treatment and incomplete responses to TAF.展开更多
Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELI...Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and Ig M antibodies detection by ELISA. Results: A total of 1 270 serum samples were tested 86%(1 097/1 270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64%(807/1 270) were positive by NS1 ELISA and 52%(662/1 270), 51%(646/1 270) were positive by real-time RT-PCR and Ig M ELISA respectively.Conclusions: NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.展开更多
Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells....Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.Methods:The ethanolic extract of C.dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus(CHIKV) fraction.Reverse phase-HPLC and GC-MS studies were carried out to identily the major phytochemicals in the fraction using phylochemical standards.Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells.Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction(RT-PCR) after treating the viral infected Vero cells with the fraction.Results:Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids,luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C.dactylon- The fraction was found to exhibit potent viral inhibitory activity(about 98%) at the concentration of 50 μg/mL as observed by reduction in cytopathic effect,and the cytotoxic concentration of the fraction was found to be 250 μg/mL.RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells.Conclusions:Luteolin and apigenin rich ethanolic fraction from C.dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus.展开更多
AIM:To investigate characteristics of hepatitis B virus(HBV)implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.METHODS:Serum samples were collected from 53 p...AIM:To investigate characteristics of hepatitis B virus(HBV)implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.METHODS:Serum samples were collected from 53 patients with hematological malignancies negative for hepatitis B surface antigen(HBsAg)before the start of and throughout the chemotherapy course.HBV reactivation was diagnosed when the HBsAg status changed from negative to positive after the initiation of chemotherapy and/or when HBV DNA was detected by realtime detection polymerase chain reaction(RTD-PCR).For detecting the serological markers of HBV infection,HBsAg as well as antibodies to the core antigen(antiHBc)and to the surface antigen were measured in the sera by CEIA.Nucleic acids were extracted from sera,and HBV DNA sequences spanning the S gene were amplified by RTD-PCR.The extracted DNA was further subjected to PCR to amplify the complete genome as well as the specific genomic sequences bearing the enhancerⅡ/core promoter/pre-core/core regions(nt1628-2364).Amplicons were sequenced directly.RESULTS:Thirty-five(66%)of the 53 HBsAg-negative patients were found to be negative serologically for antiHBc,and the remaining 18(34%)patients were positive for anti-HBc.Five of the 53(9.4%)patients with hematologic malignancies experienced HBV reactivation.Genotype D1 was detected in all five patients.Four types of mutant strains were detected in the S gene product of HBV strains and were isolated from 3 patients with HBV reactivation:T/S120,L143,and I126.HBV DNA was detected in the pretreatment HBsAg-negative samples in one of the five patients with HBV reactivation.In this patient,sequences encompassing the HBV full genome obtained from sera before the start of chemotherapy and at the time of de novo HBV hepatitis were detected and it showed 100%homology.Furthermore,in the phylogenetic tree,the sequences were clustered together,thereby indicating that this patient developed reactivation from an occult HBV infection.CONCLUSION:Past infection with HBV is a risk factor for HBV reactivation in Egypt.Mandatory anti-HBc screening prior to chemotherapy in patients with hematological malignancies is recommended.展开更多
Hepatitis C virus(HCV)is a major cause of liver disease worldwide.HCV is able to evade host defense mechanisms,including both innate and acquired immune responses,to establish persistent infection,which results in a b...Hepatitis C virus(HCV)is a major cause of liver disease worldwide.HCV is able to evade host defense mechanisms,including both innate and acquired immune responses,to establish persistent infection,which results in a broad spectrum of pathogenicity,such as lipid and glucose metabolism disorders and hepatocellular carcinoma development.The HCV genome is characterized by a high degree of genetic diversity,which can be associated with viral sensitivity or resistance(reflected by different virological responses)to interferon(IFN)-based therapy.In this regard,it is of importance to note that polymorphisms in certain HCV genomic regions have shown a close correlation with treatment outcome.In particular,among the HCV proteins,the core and nonstructural proteins(NS)5A have been extensively studied for their correlation with responses to IFN-based treatment.This review aims to cover updated information on the impact of major HCV genetic factors,including HCV genotype,mutations in amino acids 70 and91 of the core protein and sequence heterogeneity in the IFN sensitivity-determining region and IFN/ribavirin resistance-determining region of NS5A,on virological responses to IFN-based therapy.展开更多
In more than half of infertile men, the cause of their infertility is unknown. Several studies revealed the role of viral infections in male infertility. The aim of the present study was to determine the prevalence of...In more than half of infertile men, the cause of their infertility is unknown. Several studies revealed the role of viral infections in male infertility. The aim of the present study was to determine the prevalence of herpes simplex virus-1 （HSV-1） and HSV-2 in semen from asymptomatic infertile male patients, and its association with altered semen parameters. A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd, Iran. Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed. Comparison of semen parameters between virally in- fected and non-infected samples were performed with independent t-test and Mann-Whitney test. Semen analysis showed that infertile men fell into two groups, the male factor group and the unexplained group. HSV-1 and HSV-2 DNA was detected in 16 （22.9%） and 10 （14.3%） of 70 semen samples, respectively. All HSV-positive samples had abnormal semen parameters （the male factor group）. Although HSV infection was not associated with sperm motility and morphological defects, it was correlated with lower sperm count in the seminal fluid. The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely af- fecting sperm count.展开更多
Dear Editor,Enterovirus 71(EV71),a member of the genus Enterovirus of the family Picornaviridae,is a single-stranded,positive-sense RNA virus that usually causes mild handfoot-mouth disease(HFMD)in children,with sympt...Dear Editor,Enterovirus 71(EV71),a member of the genus Enterovirus of the family Picornaviridae,is a single-stranded,positive-sense RNA virus that usually causes mild handfoot-mouth disease(HFMD)in children,with symptoms such as fever,diarrhea,and herpangina(Liu et al.,2013).However,certain strains of EV71 infection can cause severe neurological complications,such as SDLY107(Sun et al.,2014).EV71 is classified into three distinct genotypes(A–C);the B and C genotypes are further divided into B1–B5 and C1–C5 genotypes,respectively,based展开更多
AIM: To investigate the reactivity of a panel of 8 mouse anti-hepatitis B surface antigen (HBsAg) monoclonal antibodies (mAbs) using a collection of 9 recombinant HBsAg mutants with a variety of amino acid substitutio...AIM: To investigate the reactivity of a panel of 8 mouse anti-hepatitis B surface antigen (HBsAg) monoclonal antibodies (mAbs) using a collection of 9 recombinant HBsAg mutants with a variety of amino acid substitutions mostly located within the “a” region.METHODS: The entire HBs genes previously cloned into a mammalian expression vector were transiently transfected into COS7 cells. Two standard unmutated sequences of the ayw and adw subtypes served as controls. Secreted mutant proteins were collected and measured by three commercial diagnostic immunoassays to assess transfection efficiency. Reactivity of anti-HBs mAbs with mutated HBsAgs was determined by sandwich enzyme-linked immunosorbent assay (ELISA).RESULTS: Reactivity of anti-HBs mAbs with mutated HBsAgs revealed different patterns. While three mutants reacted strongly with all mAbs, two mutants reacted weakly with only two mAbs and the remaining proteins displayed variable degrees of reactivity towards different mAbs. Accordingly, four groups of mAbs with different but overlapping reactivity patterns could be envisaged. One group consisting of two mAbs (37C5-S7 and 35C6-S11) was found to recognize stable linear epitopes conserved in all mutants. Mutations outside the “a” determinant at positions 120 (P→S), 123(T→N) and 161(M→T) were found to affect reactivity of these mAbs.CONCLUSION: Our findings could have important implications for biophysical studies, vaccination strategies and immunotherapy of hepatitis B virus (HBV) mutants.展开更多
Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BP...Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless展开更多
AIM: To establish a cell model harboring replicative clinical hepatitis B virus (HBV) isolates and evaluate its application in individualized selection of anti-HBV agents for chronic hepatitis B (CHB) patients. METHOD...AIM: To establish a cell model harboring replicative clinical hepatitis B virus (HBV) isolates and evaluate its application in individualized selection of anti-HBV agents for chronic hepatitis B (CHB) patients. METHODS: The full-length HBV genomic DNA from 8 CHB patients was amplified by polymerase chain reaction (PCR). All the patients were treated with lamivudine for at least seven months and finally became resistant to lamivudine. The amplified HBV DNA fragments were inserted into pHY106 vectors by Sap Ⅰ?digestion. The recombinant plasmids containing 1.1 copies of HBV genome were transiently transfected into Huh7 cell line, and the levels of HBsAg, HBeAg and intercellular HBV replicative intermediates were determined by ELISA and Southern blot analysis, respectively, with or without lamivudine and adefovir treatment. The antiviral treatment with adefovir was administered to the patients and analyzed in parallel. RESULTS: A total of 25 independent HBV isolateswere obtained from the sera of 8 patients, each patient had at least two isolates. One isolate from each individual was selected and subcloned into pHY106 vector, including 5 isolates with YVDD mutation and 3 isolates with YIDD mutation. All recombinant plasmids harboring HBV isolates were transfected into Huh7 cells. The results indicated that HBV genome carried in HBV replicons of clinical HBV isolates could effectively replicate and express in Huh7 cells. Adefovir, but not lamivudine, inhibited HBV replication both in vitro and in vivo, and in vitro inhibition was dose-dependent. CONCLUSION: The novel method described herein enables individualized selection of anti-HBV agents in clinic and is useful in future studies of antiviral therapy for CHB.展开更多
Enteric viruses are the most common cause of acute gastroenteritis （AGE） in young children and a significant public health problem globally. Hospital admissions of children under 5 years of age with diarrhea are pri...Enteric viruses are the most common cause of acute gastroenteritis （AGE） in young children and a significant public health problem globally. Hospital admissions of children under 5 years of age with diarrhea are primarily associated with group A rotavirus （RVA） infection. In this retrospective study, the population structure of viruses linked to AGE etiology in young children hospitalized with AGE in Moscow was evaluated, and molecular characterization of RYA strains was performed. Fecal specimens were collected from children under 5 years old hospitalized with AGE between 2009 and 2014 in Moscow, Russia. Multiplex real-time reverse transcription PCR was used to detect enteric viruses and for G/[P]-genotyping of isolated RVAs. Sequencing of RVA VP7 and VP4 cDNA fragments was used to validate the data obtained by PCR- genotyping. The main causes for hospitalization of children with AGE were RVA （40.1%）, followed by noroviruses （11.4%）, while adenoviruses, astroviruses, sapoviruses, enteroviruses, and orthoreoviruses were detected in 4.7%, 1.9%, 1.4%, 1.2%, and 0.2% of samples tested, respectively. Nosocomial infections, predominantly associated with RVAs and noroviruses, were detected in 24.8% of cases and occurred significantly more frequently in younger infants. The predominant RVA genotype was G4P[8], detected in 38.7% of RVA-positive cases, whereas genotypes G1P[8], G9P[8], G3P[8], and G2P[4] were found in 11.8%, 6.6%, 4.2%, and 3.3% of cases, respectively. Together, the presence of circulating RVA strains with rare VP7 and VP4 gene variants （G6 and P[9]） highlights the need to conduct continuous epidemiological monitoring of RVA infection.展开更多
Human herpes virus 6 (HHV-6) infects > 95% of humans.Primary infection which occurs mostly during the f irst 2 years of life in the form of roseola infantum,non-spe cif ic febrile illness,or an asymptomatic illness...Human herpes virus 6 (HHV-6) infects > 95% of humans.Primary infection which occurs mostly during the f irst 2 years of life in the form of roseola infantum,non-spe cif ic febrile illness,or an asymptomatic illness,results in latency.Reactivation of latent HHV-6 is common after liver transplantation.Since the majority of human beings harbor the latent virus,HHV-6 infections after liver transplantation are most probably caused by end ogenous reactivation or superinfection.In a minority of cases,primary HHV-6 infection may occur when an HHV-6-seronegative individual receives a liver allograft from an HHV-6-seropositive donor.The vast major ity of HHV-6 infections after liver transplantation are asy-mptomatic.Only in a minority of cases,when HHV-6 causes a febrile illness associated with rash and mye- losuppression,hepatitis,gastroenteritis,pneumonitis,and encephalitis after liver transplantation.In addition,HHV-6 has been implicated in a variety of indirect effects,such as allograft rejection and increased predis- pos ition to and severity of other infections,includingcytomegalovirus,hepatitis C virus,and opportunistic fungi.Because of the uncommon nature of the clinical illnesses directly attributed to HHV-6,there is currently no recommended HHV-6-specific approach prevention after liver transplantation.Asymptomatic HHV-6 infection does not require antiviral treatment,while treatment of established HHV-6 disease is treated with intravenous ganciclovir,foscarnet,or cidofovir and this should be com plemented by a reduction in immunosuppression.展开更多
AIM： To determine the prevalence of hepatitis B virus （HBV） genotypes in Iranian hepatitis B surface antigen （HBsAg） carriers, chronic hepatitis B and cirrhotic patients. METHODS： A total of 109 HBsAg-positive p...AIM： To determine the prevalence of hepatitis B virus （HBV） genotypes in Iranian hepatitis B surface antigen （HBsAg） carriers, chronic hepatitis B and cirrhotic patients. METHODS： A total of 109 HBsAg-positive patients were included in this study. HBV genotypes were determined by using INNO-LiPA methodology which is based on the reverse hybridization principle. RESULTS： The distribution of patients with different stages of liver disease was as follows： 95 （86.4%） chronic hepatitis, 11 （10%） liver cirrhosis, and 3 （2.7%） inactive carrier. Of the chronic hepatitis and liver cirrhosis patients, 26.4% were HBeAg-positive while 70% were HBeAg-negative. Genotype D was the only detected type found in all patients. CONCLUSION： Classifying HBV into genotypes has to be cost-effective and clinically relevant. Our study indicates that HBV genotype D prevails in the Mediterranean area, Near and Middle East, and South Asia. Continued efforts for understanding HBV genotype through international co-operation will reveal further virological differences of the genotypes and their clinical relevance.展开更多
The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E repre...The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E represents an emerging zoonotic infection in many European countries.The aim of this manuscript is to perform a systematic review of the published literature on hepatitis E distribution in humans,animals and environmental samples("One Health"concept)in the South-Eastern European countries.Comparison of the available data showed that the anti-HEV seroprevalence in the South-Eastern Europe varies greatly,depending on the population studied,geographical area and methods used.The IgG seroprevalence rates in different population groups were found to be 1.1%-24.5%in Croatia,up to 20.9%in Bulgaria,5.9-%17.1%in Romania,15%in Serbia,up to 9.7%in Greece and 2%-9.7%in Albania.Among possible risk factors,older age was the most significant predictor for HEV seropositivity in most studies.Higher seroprevalence rates were found in animals.HEV IgG antibodies in domestic pigs were detected in 20%-54.5%,29.2%-50%,38.94%-50%and 31.1%-91.7%in Serbia,Bulgaria,Romania and Croatia,respectively.In wild boars seroprevalence rates were up to 10.3%,30.3%and 31.1%in Romania,Slovenia and Croatia,respectively.A high HEV RNA prevalence in wild boars in some countries(Croatia and Romania)indicated that wild boars may have a key role in the HEV epidemiology.There are very few data on HEV prevalence in environmental samples.HEV RNA was detected in 3.3%and 16.7%surface waters in Slovenia and Serbia,respectively.There is no evidence of HEV RNA in sewage systems in this region.The available data on genetic characterization show that human,animal and environmental HEV strains mainly belong to the genotype 3.展开更多
Prion diseases are a group of neurodegenerative diseases that are fatal. The study of these unique diseases in China is hampered by a lack of resources. Amongst the most important resources for biological study are mo...Prion diseases are a group of neurodegenerative diseases that are fatal. The study of these unique diseases in China is hampered by a lack of resources. Amongst the most important resources for biological study are monoclonal antibodies. Here, we characterize a panel of monoclonal antibodies specific for cellular prion protein by enzyme-linked immunosorbent assay(ELISA), immunofluorescent staining, flow cytometry, and western blotting. We identify several antibodies that can be used for specific applications and we demonstrate that there is no prion protein expression in human pancreatic ductal epithelial cells(HPDC).展开更多
In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab sample...In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab samples from sheep pox (SP) suspected sheep were collected.Hyperimmune rabbit sera to Lumpy skin disease virus (LSDV)/Ismailyia88 strain and sheep pox virus (SPV)/ Kenyan vaccinal strain were prepared.The causative agent in the collected samples was identified using immunoflourescence (IF) and immunoperoxidase techniques.Of the 15 skin nodules suspected of LSD,10 showed a positive reaction and 3 out of 5 skin scabs suspected of sheeppox were found to be positive.An antigenic correlation between field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV/Kenyan vaccinal strain was studied using prepared hyperimmune sera.Also,nucleotide sequence of the PCR amplified attachment gene fragments of field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV /Kenyan vaccinal strain were compared.The results revealed that the four used viruses were antigenically identical.Sequence analysis indicated that field skin LSDV isolate is more related to tissue culture adapted LSDV/Ismailyia88 strain than to vaccinal SPV/ Kenyan strain and the skin isolate of SPV is more closely related to field skin isolate of LSDV than to SPV/Kenyan vaccinal strain.Thus,further study should be applied on the advantage of a LSD vaccine prepared from LSDV in protection of cattle against LSD compared to the commonly used sheep pox vaccine.展开更多
Infection with high-risk human papillomavirus(HPV),including HPV-16 and HPV-18,is the main cause of malignancies,such as cervical cancer.Viral oncoproteins encoded by HPV are expressed in HPV-positive cancers and asso...Infection with high-risk human papillomavirus(HPV),including HPV-16 and HPV-18,is the main cause of malignancies,such as cervical cancer.Viral oncoproteins encoded by HPV are expressed in HPV-positive cancers and associated with the early cancer stages and the transformation of normal cells.The signaling pathways involved in the transformation of normal cells to cancerous form and the subsequently expressed programmed cell death-ligand 1(PD-L1)on the surface of the transformed cells lead to a disruption in recognition of tumor cells by the immune cell system,including T lymphocytes and dendritic cells which lead to the development of cervical cancer malignancy.These cells also produce modest levels of cytokines during exhaustion,tumor-infiltrating T CD4+cells with high levels of PD-1 and CD39 release considerable quantities of cytokines.The Wnt/β-catenin signaling pathway,which controls the expression of genes involved in the tumor cells’markers,is demonstrated to be one of the most potent cancer stimulants.It leads to the evasion of the tumor cells from immune cell detection and ultimately avoids being recognized by dendritic cells or T-cells.PD-L1,as an inhibitory immune checkpoint,is essential for controlling immune system activity by inhibiting T-cells’inflammatory function.In the present review,we looked into how Wnt/β-catenin affects the expression of PD-L1 and related genes like c-MYC in cancer cells and its role in the development of HPV-induced malignancy.We hypothesized that blocking these pathways could be a potential immunotherapy and cancer prevention method.展开更多
文摘Hepatitis C virus (HCV) infects approximately 170 million individuals worldwide. Prevention of HCV infection complications is based on antiviral therapy with the combination of pegylated interferon alfa and ribavirin. The use of serological and virological tests has become essential in the management of HCV infection in order to diagnose infection, guide treatment decisions and assess the virological response to antiviral therapy. Anti- HCV antibody testing and HCV RNA testing are used to diagnose acute and chronic hepatitis C. The HCV genotype should be systematically determined before treatment, as it determines the indication, the duration of treatment, the dose of ribavirin and the virological monitoring procedure. HCV RNA monitoring during therapy is used to tailor treatment duration in HCV genotype 1 infection, and molecular assays are used to assess the end-of-treatment and, most importantly the sustained virological response, i.e. the endpoint of therapy.
文摘The World Society for Virology(WSV) was founded and incorporated as a nonprofit organization in the United States in 2017. WSV seeks to strengthen and support both virological research and virologists who conduct research of viruses that affect humans, other animals, plants, and other organisms. One of the objectives of WSV is to connect virologists worldwide and support collaboration. Fulfilling this objective, virologists from fourteen countries in North America,Europe, Africa, Asia, and the Middle East met on 25–27 th August 2019 in Stockholm, Sweden at the Karolinska University Hospital for the first Committee Meeting of WSV. This meeting included compelling keynote and honorary speeches and a series of 18 scientific talks were given encompassing a diverse array of subjects within virology. Followed by the scientific session, a business session was held where multiple aspects and next steps of the society were discussed and charted out.
文摘BACKGROUND The emergence of the Omicron variant(B.1.1.529)of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)raised global concerns with its highly transmissible nature.AIM To investigate the genomic,clinical,and demographic characteristics of Omicron infections within the early outbreak cluster in western part of Sri Lanka.METHODS We analyzed sequence data from January 2022 to April 2022 to understand variant dynamics,clinical presentation,and demographic associations.RESULTS Whole-genome sequencing of 85 nasopharyngeal and throat swab samples collected in western part of Sri Lanka between January and April 2022 identified 70(82.34%)of it as Omicron variants.BA.2 was the most prevalent sub-lineage(57%),followed by BA.1.1(14.20%)and majority of them were from>12 years old individuals.Phylogenetic analysis revealed clustering into four distinct clades(21I,21K,21L,and 21M),suggesting potential differences in transmission chains or evolutionary pressures.CONCLUSION This study found BA.2 to be the predominant Omicron sub-lineage in the western part of Sri Lanka during the first quarter of 2022,aligning with global trends.Phylogenetic analysis revealed diverse introductions and local transmission.Continued genomic surveillance and robust public health measures remain crucial for managing the evolving SARS-CoV-2 landscape.
基金Supported by the Japan Agency for Medical Research and Development(AMED),No.JP22fk0310503.
文摘BACKGROUND Tenofovir alafenamide fumarate(TAF)is one of the first-line treatments used to treat chronic hepatitis B patients;TAF has strong antiviral activity and a high barrier to resistance.Although virological breakthroughs in patients during TAF treatment are rare,patients with incomplete responses to TAF are occasionally observed.AIM To investigate responsible mutations in the reverse transcriptase region of hepatitis B virus(HBV)for TAF-incomplete responses.METHODS Thirteen chronic hepatitis B patients who received TAF monotherapy were included.A TAF-incomplete responder was defined as one who was continuously positive for HBV DNA over 2 years after TAF treatment initiation.The emergences of mutations in TAF-incomplete responders were evaluated before,one year after,and two years after treatment by deep sequencing of HBV DNA and RNA.RESULTS Two patients were continuously positive for HBV DNA over two years.The rtL269I mutation,one of the CYEI mutations linked to tenofovir resistance,was detected in both patients by direct sequencing.The deep sequencing analysis revealed that a combination of rtT118A and rtL220I mutations and the rtL269I mutation were predominantly detected in HBV DNA even when these mutations were barely detected in HBV RNA.This suggests a superior replication capability of the HBV variants with these mutations under TAF treatment.CONCLUSION The deep sequencing analysis of HBV DNA and RNA and comparing the detection rates of mutations were useful for estimating responsible mutations for TAF-incomplete responses.Such analysis is needed to evaluate the association between mutations that emerge during TAF treatment and incomplete responses to TAF.
文摘Objective: To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods: The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and Ig M antibodies detection by ELISA. Results: A total of 1 270 serum samples were tested 86%(1 097/1 270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64%(807/1 270) were positive by NS1 ELISA and 52%(662/1 270), 51%(646/1 270) were positive by real-time RT-PCR and Ig M ELISA respectively.Conclusions: NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.
文摘Objective:To obtain Iuteolin and apigenin rich fraction from the ethanolic extract of Cynodon dactylon(L.)(C.dactylon) Pers and evaluate the fraction's cytotoxicity and anti-Chikungunya potential using Vero cells.Methods:The ethanolic extract of C.dactylon was subjected to silica gel column chromatography to obtain anti-chikungunya virus(CHIKV) fraction.Reverse phase-HPLC and GC-MS studies were carried out to identily the major phytochemicals in the fraction using phylochemical standards.Cytotoxicity and the potential of the fraction against CHIKV were evaluated in vitro using Vero cells.Reduction in viral replication was assessed by reverse transcriptase-polymerase chain reaction(RT-PCR) after treating the viral infected Vero cells with the fraction.Results:Reverse Phase-HPLC and GC-MS studies confirmed the presence of flavonoids,luteolin and apigenin as major phytochemicals in the anti-CHIKV ethanolic fraction of C.dactylon- The fraction was found to exhibit potent viral inhibitory activity(about 98%) at the concentration of 50 μg/mL as observed by reduction in cytopathic effect,and the cytotoxic concentration of the fraction was found to be 250 μg/mL.RT-PCR analyses indicated that the reduction in viral mRNA synthesis in fraction treated infected cells was much higher than the viral infected control cells.Conclusions:Luteolin and apigenin rich ethanolic fraction from C.dactylon can be utilized as a potential therapeutic agent against CHIKV infection as the fraction does not show cytotoxicity while inhibiting the virus.
基金Supported by The Grant for National Center For Global Health and Medicine(22A-9)a Grant-in-Aid form Japan Society for the Promotion of Science(JSPS) Fellows(21.09355)a Grant-in-Aid form the Ministry of Health,Labour and Welfare of Japan
文摘AIM:To investigate characteristics of hepatitis B virus(HBV)implicated in HBV reactivation in patients with hematological malignancies receiving immunosuppressive therapy.METHODS:Serum samples were collected from 53 patients with hematological malignancies negative for hepatitis B surface antigen(HBsAg)before the start of and throughout the chemotherapy course.HBV reactivation was diagnosed when the HBsAg status changed from negative to positive after the initiation of chemotherapy and/or when HBV DNA was detected by realtime detection polymerase chain reaction(RTD-PCR).For detecting the serological markers of HBV infection,HBsAg as well as antibodies to the core antigen(antiHBc)and to the surface antigen were measured in the sera by CEIA.Nucleic acids were extracted from sera,and HBV DNA sequences spanning the S gene were amplified by RTD-PCR.The extracted DNA was further subjected to PCR to amplify the complete genome as well as the specific genomic sequences bearing the enhancerⅡ/core promoter/pre-core/core regions(nt1628-2364).Amplicons were sequenced directly.RESULTS:Thirty-five(66%)of the 53 HBsAg-negative patients were found to be negative serologically for antiHBc,and the remaining 18(34%)patients were positive for anti-HBc.Five of the 53(9.4%)patients with hematologic malignancies experienced HBV reactivation.Genotype D1 was detected in all five patients.Four types of mutant strains were detected in the S gene product of HBV strains and were isolated from 3 patients with HBV reactivation:T/S120,L143,and I126.HBV DNA was detected in the pretreatment HBsAg-negative samples in one of the five patients with HBV reactivation.In this patient,sequences encompassing the HBV full genome obtained from sera before the start of chemotherapy and at the time of de novo HBV hepatitis were detected and it showed 100%homology.Furthermore,in the phylogenetic tree,the sequences were clustered together,thereby indicating that this patient developed reactivation from an occult HBV infection.CONCLUSION:Past infection with HBV is a risk factor for HBV reactivation in Egypt.Mandatory anti-HBc screening prior to chemotherapy in patients with hematological malignancies is recommended.
基金Supported by A Health and Labour Sciences Research Grant from the Ministry of Health,Labour and Welfare,Japan,a SATREPS Grant from Japan Science and Technology Agency and Japan International Cooperation Agencythe Japan Initiative for Global Research Network on Infectious Diseases(J-GRID)program from the Ministry of Education,Culture,Sports,Science and Technology,Japan
文摘Hepatitis C virus(HCV)is a major cause of liver disease worldwide.HCV is able to evade host defense mechanisms,including both innate and acquired immune responses,to establish persistent infection,which results in a broad spectrum of pathogenicity,such as lipid and glucose metabolism disorders and hepatocellular carcinoma development.The HCV genome is characterized by a high degree of genetic diversity,which can be associated with viral sensitivity or resistance(reflected by different virological responses)to interferon(IFN)-based therapy.In this regard,it is of importance to note that polymorphisms in certain HCV genomic regions have shown a close correlation with treatment outcome.In particular,among the HCV proteins,the core and nonstructural proteins(NS)5A have been extensively studied for their correlation with responses to IFN-based treatment.This review aims to cover updated information on the impact of major HCV genetic factors,including HCV genotype,mutations in amino acids 70 and91 of the core protein and sequence heterogeneity in the IFN sensitivity-determining region and IFN/ribavirin resistance-determining region of NS5A,on virological responses to IFN-based therapy.
基金supported by Tehran University of Medical Sciences(No.P/943)
文摘In more than half of infertile men, the cause of their infertility is unknown. Several studies revealed the role of viral infections in male infertility. The aim of the present study was to determine the prevalence of herpes simplex virus-1 （HSV-1） and HSV-2 in semen from asymptomatic infertile male patients, and its association with altered semen parameters. A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd, Iran. Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed. Comparison of semen parameters between virally in- fected and non-infected samples were performed with independent t-test and Mann-Whitney test. Semen analysis showed that infertile men fell into two groups, the male factor group and the unexplained group. HSV-1 and HSV-2 DNA was detected in 16 （22.9%） and 10 （14.3%） of 70 semen samples, respectively. All HSV-positive samples had abnormal semen parameters （the male factor group）. Although HSV infection was not associated with sperm motility and morphological defects, it was correlated with lower sperm count in the seminal fluid. The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely af- fecting sperm count.
基金supported by National Natural Science Foundation of China(81371833)Medical and Health Science and Technology Development Plan of Shandong Province(2013WS0211)approved by the ethical committees of School of Public Health,Shandong University,Jinan,Shandong 250012,China(permit number 20080301)
文摘Dear Editor,Enterovirus 71(EV71),a member of the genus Enterovirus of the family Picornaviridae,is a single-stranded,positive-sense RNA virus that usually causes mild handfoot-mouth disease(HFMD)in children,with symptoms such as fever,diarrhea,and herpangina(Liu et al.,2013).However,certain strains of EV71 infection can cause severe neurological complications,such as SDLY107(Sun et al.,2014).EV71 is classified into three distinct genotypes(A–C);the B and C genotypes are further divided into B1–B5 and C1–C5 genotypes,respectively,based
基金Supported by Tehran University of Medical Sciences
文摘AIM: To investigate the reactivity of a panel of 8 mouse anti-hepatitis B surface antigen (HBsAg) monoclonal antibodies (mAbs) using a collection of 9 recombinant HBsAg mutants with a variety of amino acid substitutions mostly located within the “a” region.METHODS: The entire HBs genes previously cloned into a mammalian expression vector were transiently transfected into COS7 cells. Two standard unmutated sequences of the ayw and adw subtypes served as controls. Secreted mutant proteins were collected and measured by three commercial diagnostic immunoassays to assess transfection efficiency. Reactivity of anti-HBs mAbs with mutated HBsAgs was determined by sandwich enzyme-linked immunosorbent assay (ELISA).RESULTS: Reactivity of anti-HBs mAbs with mutated HBsAgs revealed different patterns. While three mutants reacted strongly with all mAbs, two mutants reacted weakly with only two mAbs and the remaining proteins displayed variable degrees of reactivity towards different mAbs. Accordingly, four groups of mAbs with different but overlapping reactivity patterns could be envisaged. One group consisting of two mAbs (37C5-S7 and 35C6-S11) was found to recognize stable linear epitopes conserved in all mutants. Mutations outside the “a” determinant at positions 120 (P→S), 123(T→N) and 161(M→T) were found to affect reactivity of these mAbs.CONCLUSION: Our findings could have important implications for biophysical studies, vaccination strategies and immunotherapy of hepatitis B virus (HBV) mutants.
文摘Dear Editor,The Poxviridae family is divided into Chordopoxvirinae and Entomopoxvirinae genera.Parapoxvirus is one of 11genera in the Chordopoxvirinae genus,including orf virus(ORFV),bovine papular stomatitis virus(BPSV),pseudocowpox virus(PCPV)and parapoxvirus of red deer in New Zealand(PVNZ)(Skinner et al.,2012).This virus,also known as contagious ecthyma or contagious pustular dermatitis,is a viral skin disease causing edematous proliferative lesions,most often in hairless
基金The National Natural Science Foundation of China, No. 30271170the Ph.D. Program Fund of Chinese Ministry of Education, No. 20070487152
文摘AIM: To establish a cell model harboring replicative clinical hepatitis B virus (HBV) isolates and evaluate its application in individualized selection of anti-HBV agents for chronic hepatitis B (CHB) patients. METHODS: The full-length HBV genomic DNA from 8 CHB patients was amplified by polymerase chain reaction (PCR). All the patients were treated with lamivudine for at least seven months and finally became resistant to lamivudine. The amplified HBV DNA fragments were inserted into pHY106 vectors by Sap Ⅰ?digestion. The recombinant plasmids containing 1.1 copies of HBV genome were transiently transfected into Huh7 cell line, and the levels of HBsAg, HBeAg and intercellular HBV replicative intermediates were determined by ELISA and Southern blot analysis, respectively, with or without lamivudine and adefovir treatment. The antiviral treatment with adefovir was administered to the patients and analyzed in parallel. RESULTS: A total of 25 independent HBV isolateswere obtained from the sera of 8 patients, each patient had at least two isolates. One isolate from each individual was selected and subcloned into pHY106 vector, including 5 isolates with YVDD mutation and 3 isolates with YIDD mutation. All recombinant plasmids harboring HBV isolates were transfected into Huh7 cells. The results indicated that HBV genome carried in HBV replicons of clinical HBV isolates could effectively replicate and express in Huh7 cells. Adefovir, but not lamivudine, inhibited HBV replication both in vitro and in vivo, and in vitro inhibition was dose-dependent. CONCLUSION: The novel method described herein enables individualized selection of anti-HBV agents in clinic and is useful in future studies of antiviral therapy for CHB.
基金RVA G/[P]-genotypes was at the expense of the Russian Science Foundation(Grant No.16-15-10332)
文摘Enteric viruses are the most common cause of acute gastroenteritis （AGE） in young children and a significant public health problem globally. Hospital admissions of children under 5 years of age with diarrhea are primarily associated with group A rotavirus （RVA） infection. In this retrospective study, the population structure of viruses linked to AGE etiology in young children hospitalized with AGE in Moscow was evaluated, and molecular characterization of RYA strains was performed. Fecal specimens were collected from children under 5 years old hospitalized with AGE between 2009 and 2014 in Moscow, Russia. Multiplex real-time reverse transcription PCR was used to detect enteric viruses and for G/[P]-genotyping of isolated RVAs. Sequencing of RVA VP7 and VP4 cDNA fragments was used to validate the data obtained by PCR- genotyping. The main causes for hospitalization of children with AGE were RVA （40.1%）, followed by noroviruses （11.4%）, while adenoviruses, astroviruses, sapoviruses, enteroviruses, and orthoreoviruses were detected in 4.7%, 1.9%, 1.4%, 1.2%, and 0.2% of samples tested, respectively. Nosocomial infections, predominantly associated with RVAs and noroviruses, were detected in 24.8% of cases and occurred significantly more frequently in younger infants. The predominant RVA genotype was G4P[8], detected in 38.7% of RVA-positive cases, whereas genotypes G1P[8], G9P[8], G3P[8], and G2P[4] were found in 11.8%, 6.6%, 4.2%, and 3.3% of cases, respectively. Together, the presence of circulating RVA strains with rare VP7 and VP4 gene variants （G6 and P[9]） highlights the need to conduct continuous epidemiological monitoring of RVA infection.
文摘Human herpes virus 6 (HHV-6) infects > 95% of humans.Primary infection which occurs mostly during the f irst 2 years of life in the form of roseola infantum,non-spe cif ic febrile illness,or an asymptomatic illness,results in latency.Reactivation of latent HHV-6 is common after liver transplantation.Since the majority of human beings harbor the latent virus,HHV-6 infections after liver transplantation are most probably caused by end ogenous reactivation or superinfection.In a minority of cases,primary HHV-6 infection may occur when an HHV-6-seronegative individual receives a liver allograft from an HHV-6-seropositive donor.The vast major ity of HHV-6 infections after liver transplantation are asy-mptomatic.Only in a minority of cases,when HHV-6 causes a febrile illness associated with rash and mye- losuppression,hepatitis,gastroenteritis,pneumonitis,and encephalitis after liver transplantation.In addition,HHV-6 has been implicated in a variety of indirect effects,such as allograft rejection and increased predis- pos ition to and severity of other infections,includingcytomegalovirus,hepatitis C virus,and opportunistic fungi.Because of the uncommon nature of the clinical illnesses directly attributed to HHV-6,there is currently no recommended HHV-6-specific approach prevention after liver transplantation.Asymptomatic HHV-6 infection does not require antiviral treatment,while treatment of established HHV-6 disease is treated with intravenous ganciclovir,foscarnet,or cidofovir and this should be com plemented by a reduction in immunosuppression.
基金Supported by Tehran Hepatitis Center, Keivan Virology Lab
文摘AIM： To determine the prevalence of hepatitis B virus （HBV） genotypes in Iranian hepatitis B surface antigen （HBsAg） carriers, chronic hepatitis B and cirrhotic patients. METHODS： A total of 109 HBsAg-positive patients were included in this study. HBV genotypes were determined by using INNO-LiPA methodology which is based on the reverse hybridization principle. RESULTS： The distribution of patients with different stages of liver disease was as follows： 95 （86.4%） chronic hepatitis, 11 （10%） liver cirrhosis, and 3 （2.7%） inactive carrier. Of the chronic hepatitis and liver cirrhosis patients, 26.4% were HBeAg-positive while 70% were HBeAg-negative. Genotype D was the only detected type found in all patients. CONCLUSION： Classifying HBV into genotypes has to be cost-effective and clinically relevant. Our study indicates that HBV genotype D prevails in the Mediterranean area, Near and Middle East, and South Asia. Continued efforts for understanding HBV genotype through international co-operation will reveal further virological differences of the genotypes and their clinical relevance.
文摘The significance of hepatitis E virus(HEV)as an important public health problem is rising.Until a decade ago,cases of HEV infection in Eur-ope were mainly confined to returning travelers,but nowadays,hepatitis E represents an emerging zoonotic infection in many European countries.The aim of this manuscript is to perform a systematic review of the published literature on hepatitis E distribution in humans,animals and environmental samples("One Health"concept)in the South-Eastern European countries.Comparison of the available data showed that the anti-HEV seroprevalence in the South-Eastern Europe varies greatly,depending on the population studied,geographical area and methods used.The IgG seroprevalence rates in different population groups were found to be 1.1%-24.5%in Croatia,up to 20.9%in Bulgaria,5.9-%17.1%in Romania,15%in Serbia,up to 9.7%in Greece and 2%-9.7%in Albania.Among possible risk factors,older age was the most significant predictor for HEV seropositivity in most studies.Higher seroprevalence rates were found in animals.HEV IgG antibodies in domestic pigs were detected in 20%-54.5%,29.2%-50%,38.94%-50%and 31.1%-91.7%in Serbia,Bulgaria,Romania and Croatia,respectively.In wild boars seroprevalence rates were up to 10.3%,30.3%and 31.1%in Romania,Slovenia and Croatia,respectively.A high HEV RNA prevalence in wild boars in some countries(Croatia and Romania)indicated that wild boars may have a key role in the HEV epidemiology.There are very few data on HEV prevalence in environmental samples.HEV RNA was detected in 3.3%and 16.7%surface waters in Slovenia and Serbia,respectively.There is no evidence of HEV RNA in sewage systems in this region.The available data on genetic characterization show that human,animal and environmental HEV strains mainly belong to the genotype 3.
基金the National Natural Sciences Foundation of China(81172376,31270209)the 100 talent-program of the Chinese Academy of Sciencesthe State Key Laboratory of Virology for financial support
文摘Prion diseases are a group of neurodegenerative diseases that are fatal. The study of these unique diseases in China is hampered by a lack of resources. Amongst the most important resources for biological study are monoclonal antibodies. Here, we characterize a panel of monoclonal antibodies specific for cellular prion protein by enzyme-linked immunosorbent assay(ELISA), immunofluorescent staining, flow cytometry, and western blotting. We identify several antibodies that can be used for specific applications and we demonstrate that there is no prion protein expression in human pancreatic ductal epithelial cells(HPDC).
文摘In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab samples from sheep pox (SP) suspected sheep were collected.Hyperimmune rabbit sera to Lumpy skin disease virus (LSDV)/Ismailyia88 strain and sheep pox virus (SPV)/ Kenyan vaccinal strain were prepared.The causative agent in the collected samples was identified using immunoflourescence (IF) and immunoperoxidase techniques.Of the 15 skin nodules suspected of LSD,10 showed a positive reaction and 3 out of 5 skin scabs suspected of sheeppox were found to be positive.An antigenic correlation between field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV/Kenyan vaccinal strain was studied using prepared hyperimmune sera.Also,nucleotide sequence of the PCR amplified attachment gene fragments of field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV /Kenyan vaccinal strain were compared.The results revealed that the four used viruses were antigenically identical.Sequence analysis indicated that field skin LSDV isolate is more related to tissue culture adapted LSDV/Ismailyia88 strain than to vaccinal SPV/ Kenyan strain and the skin isolate of SPV is more closely related to field skin isolate of LSDV than to SPV/Kenyan vaccinal strain.Thus,further study should be applied on the advantage of a LSD vaccine prepared from LSDV in protection of cattle against LSD compared to the commonly used sheep pox vaccine.
基金supported by the Immunology Research Center,Tabriz University of Medical Sciences,Tabriz,Iran.
文摘Infection with high-risk human papillomavirus(HPV),including HPV-16 and HPV-18,is the main cause of malignancies,such as cervical cancer.Viral oncoproteins encoded by HPV are expressed in HPV-positive cancers and associated with the early cancer stages and the transformation of normal cells.The signaling pathways involved in the transformation of normal cells to cancerous form and the subsequently expressed programmed cell death-ligand 1(PD-L1)on the surface of the transformed cells lead to a disruption in recognition of tumor cells by the immune cell system,including T lymphocytes and dendritic cells which lead to the development of cervical cancer malignancy.These cells also produce modest levels of cytokines during exhaustion,tumor-infiltrating T CD4+cells with high levels of PD-1 and CD39 release considerable quantities of cytokines.The Wnt/β-catenin signaling pathway,which controls the expression of genes involved in the tumor cells’markers,is demonstrated to be one of the most potent cancer stimulants.It leads to the evasion of the tumor cells from immune cell detection and ultimately avoids being recognized by dendritic cells or T-cells.PD-L1,as an inhibitory immune checkpoint,is essential for controlling immune system activity by inhibiting T-cells’inflammatory function.In the present review,we looked into how Wnt/β-catenin affects the expression of PD-L1 and related genes like c-MYC in cancer cells and its role in the development of HPV-induced malignancy.We hypothesized that blocking these pathways could be a potential immunotherapy and cancer prevention method.
