Enterovirus D68(EV-D68)and enterovirus A71(EV-A71)are two major types of enteroviruses that pose emerging challenges to public health and have the potential to cause outbreaks,yet their pathogenic mechanisms remain la...Enterovirus D68(EV-D68)and enterovirus A71(EV-A71)are two major types of enteroviruses that pose emerging challenges to public health and have the potential to cause outbreaks,yet their pathogenic mechanisms remain largely unexplored.Arrestin domain containing 3(ARRDC3)is a vital regulator of glucose metabolism,cancer development,and inflammation.Whether ARRDC3 contributes to innate antiviral immunity is undefined.Here,we found that enterovirus infection induces ARRDC3 expression at both the mRNA and protein levels,thereby inhibiting enterovirus replication.Moreover,we demonstrate that the expression of Yes-associated protein(YAP),a key effector of the Hippo pathway,is severely downregulated by ARRDC3 via lysosomal pathway.YAP facilitates enterovirus replication by suppressing the interferon pathway during the later stage of enterovirus infection,independent of its transcriptional activity.Finally,the ARRDC3-YAP pathway exhibits a broad-spectrum antiviral effect in various viral infections,including those caused by human parainfluenza virus type 3(HPIV3)and vesicular stomatitis virus(VSV).Collectively,our results identify the critical role of ARRDC3 and its negative regulatory effect on YAP in the innate antiviral response,suggesting a novel therapeutic strategy against virus infection.展开更多
Enterovirus A71(EV-A71)is the major causative pathogen for severe hand-foot-mouth disease(HFMD),a predominantly childhood-associated communicable disease.The mechanisms that children manifest severe disease progressio...Enterovirus A71(EV-A71)is the major causative pathogen for severe hand-foot-mouth disease(HFMD),a predominantly childhood-associated communicable disease.The mechanisms that children manifest severe disease progression while adults typically exhibit milder or asymptomatic infections remain incompletely characterized,which hinders the development of effective therapy against this disease.Herein,using the newborn mouse model of EV-A71 infection,we uncovered that the underdevelopment of T cells closely associated with the severity of EV-A71 infection,and EV-A71 infection dramatically impaired T-cell immune response.Moreover,the dysfunction of T-cell immunity contributes to the pathogenesis of EV-A71 infection,as the loss of T cells made neonatal mice highly vulnerable to EV-A71 infection.To further assess the relationship between T-cell immunity and HFMD,we enrolled a cohort of 145 pediatric patients with laboratory-confirmed EV-A71 infection and found that the compromised T-cell immune response is associated with the severity of EV-A71-caused HFMD in these children.Furthermore,we found that the treatment of newborn mice with Astragaloside A,a saponin from the medicinal herb Astragalus membranaceus,showed potent in vivo therapeutic efficacy against EV-A71 infection in a T-cell-dependent manner.In conclusion,these findings uncover the interaction between EV-A71 infection and T-cell immunity,provide novel insights onto the physiological impacts of T cells on the pathogenesis of EV-A71 infection and HFMD,and find a promising immunotherapeutic strategy to treat this viral disease.展开更多
Enteroviruses(EVs)species A are a major public health issue in the Asia–Pacific region and cause frequent epidemics of hand,foot and mouth disease(HFMD)in China.Mild infections are common in children;however,HFMD can...Enteroviruses(EVs)species A are a major public health issue in the Asia–Pacific region and cause frequent epidemics of hand,foot and mouth disease(HFMD)in China.Mild infections are common in children;however,HFMD can also cause severe illness that affects the central nervous system.To molecularly characterize EVs,a prospective HFMD virological surveillance program was performed in China between 2013 and 2016.Throat swabs,rectal swabs and stool samples were collected from suspected HFMD patients at participating hospitals.EVs were detected using generic real-time and nested reverse transcription-polymerase chain reactions(RT-PCRs).Then,the complete VP1 regions of enterovirus A71(EV-A71),coxsackievirus A16(CVA16)and CVA6 were sequenced to analyze amino acid changes and construct a viral molecular phylogeny.Of the 2836 enrolled HFMD patients,2,517(89%)were EV positive.The most frequently detected EVs were CVA16(32.5%,819),CVA6(31.2%,785),and EV-A71(20.4%,514).The subgenogroups CVA16B1 b,CVA6D3 a and EV-A71C4 a were predominant in China and recombination was not observed in the VP1 region.Sequence analysis revealed amino acid variations at the 30,29 and 44 positions in the VP1 region of EV-A71,CVA16 and CVA6(compared to the respective prototype strains Br Cr,G10 and Gdula),respectively.Furthermore,in 21 of 24(87.5%)identified EV-A71 samples,a known amino acid substitution(D31 N)that may enhance neurovirulence was detected.Our study provides insights about the genetic characteristics of common HFMD-associated EVs.However,the emergence and virulence of the described mutations require further investigation.展开更多
AIM: Enterovirus 71 (EV71) has been implicated as the etiological agent responsible for the recent outbreaks of hand, foot and mouth disease associated with severe neurological diseases in the Asia-Pacific region. ...AIM: Enterovirus 71 (EV71) has been implicated as the etiological agent responsible for the recent outbreaks of hand, foot and mouth disease associated with severe neurological diseases in the Asia-Pacific region. METHODS: The assembly process was hypothesized to occur via an orchestrated proteolytic processing of the P1 precursor by the viral protease 3CD. To test this hypothesis, we constructed 3 recombinant baculoviruses: Bac-P1 expressing P1; Bac-3CD expressing 3CD; and Bac-P1-3CD co-expressing P1 and 3CD. RESULTS: Both single infection by Bac-P1-3CD and coinfection by Bac-P1 and Bac-3CD resulted in correct cleavage of P1 to yield individual proteins VP0, VP1 and VP3, while the former approach yielded higher VLP production. In the cells, the structural proteins selfassembled into clusters of virus-like particles (VLP) resembling the authentic EV71 particle aggregates. After ultracentrifugation purification, the dispersed VLPs were indistinguishable from the authentic virus in size, appearance, composition and surface epitopes, as determined by SDS-PAGE, Western blot, transmission electron microscopy and immunogold labeling. CONCLUSION: Our data, for the first time, suggest that in insect cells EV71 structural proteins adopt a processing and assembly pathway similar to poliovirus assembly. The preservation of particle morphology and composition suggest that the VLP may be a valuable vaccine candidate to prevent EV71 epidemics.展开更多
Hand, foot and mouth disease(HFMD) is a major public health concern in China. The most predominant enteroviruses that cause HFMD have traditionally been attributed to enterovirus A71(EVA71) and coxsackievirus A16(CVA1...Hand, foot and mouth disease(HFMD) is a major public health concern in China. The most predominant enteroviruses that cause HFMD have traditionally been attributed to enterovirus A71(EVA71) and coxsackievirus A16(CVA16). Since its first large outbreak in 2008, the dominant HFMD pathogens are constantly changing. In 2013 and 2015, CVA6 exceeded both EVA71 and CVA16 to become the leading cause of HFMD in some provinces. However, there still lacks a comprehensive overview on the molecular epidemiology and evolution of HFMD-related enteroviruses at the national level. In this study, we performed systematic epidemiological analyses of HFMD-related enteroviruses using the data of 64 published papers that met the inclusion criteria, and conducted phylogenetic analyses based on 12,080 partial VP1 sequences identified in China before 31 st June 2018. We found that EVA71 prevalence has decreased sharply but other enteroviruses have increased rapidly from 2008 to 2016 and that one subtype of each enterovirus is represented during the epidemic. In addition, four genotypes EVA71_C4, CVA16_B1, CVA6_D and CVA10_C are the most predominant enterovirus strains and collectively they cause over 90% of all HFMD cases in China according to the phylogenetic trees using representative partial VP1 sequences. These four major enterovirus genotypes have different geographical distributions, and they may cocirculate with other genotypes and serotypes. These results suggest that more molecular epidemiological studies should be performed on several enteroviruses simultaneously, and such information should have implications for virological surveillance, disease management, vaccine development and policy-making on the prevention and control of HFMD.展开更多
Hand foot and mouth disease is a febrile sickness complex characterized by cutaneous eruption (exanthem) on the palms and soles with simultaneous occurrence of muco-cutanous vesiculo-ulcerative lesions (enanthem) affe...Hand foot and mouth disease is a febrile sickness complex characterized by cutaneous eruption (exanthem) on the palms and soles with simultaneous occurrence of muco-cutanous vesiculo-ulcerative lesions (enanthem) affecting the mouth. The illness is caused by a number of enteroviruses with coxsackievirus A16 and enterovirus 71 as the main causative agents. Human enterovirus 71 (EV71) belongs to the species Human enterovirus A under the genus Enterovirus within the family Picornaviridae. EV71 has been associated with an array of clinical diseases including hand foot and mouth disease (HFMD), aseptic meningitis, encephalitis and poliomyelitis-like acute flaccid paralysis. A large outbreak of HFMD due to highly neurovirulent EV71 emerged in Malaysia in 1997, and caused 41 deaths amongst young children. In late 2000, a recurrence of an outbreak of HFMD occurred in Malaysia with 8 fatalities in peninsular Malaysia. Outbreak of HFMD due to EV71 recurred in 2003 with an unknown number of cases and mortalities. A similar outbreak of HFMD with 2 recorded deaths in young children occurred in peninsular Malaysia in late 2005 and this was followed by a larger outbreak in Sarawak (Malaysian Borneo) with 6 reported fatalities in the early part of 2006. The current on-going outbreak of HFMD started in peninsular Malaysia in epidemiological week 12 of 2010. As with other HFMD outbreaks in Malaysia, both EV71 and CA16 were the main aetiological viruses isolated. In similarity with the HFMD outbreak in 2005, the isolation of CA16 preceded the appearance of EV71. Based on the VP1 gene nucleotide sequences, 4 sub-genogroups of EV71 (C1, C2, B3 and B4) co-circulated and caused the outbreak of hand, foot and mouth disease in peninsular Malaysia in 1997. Two sub-genogroups (C1 and B4) were noted to cause the outbreak in 2000 in both peninsular Malaysia and Sarawak. EV71 of sub-genogroup B5 with smaller contribution from sub-genogroup C1 caused the outbreak in 2003. In the 2005 outbreak, besides the EV71 strains of sub-genogroup C1, EV71 strains belonging to sub-genogroup B5 were isolated but formed a cluster which was distinct from the EV71 strains from the sub-genogroup B5 isolated in 2003. The four EV71 strains isolated from clinical specimens of patients with hand, foot and mouth disease in the Sarawak outbreak in early 2006 also belonged to sub-genogroup B5. Phylogenetic analysis of the VP1 gene suggests that the EV71 strains causing the outbreak in Sarawak could have originated from peninsular Malaysia. Epidemiological and molecular data since 1997 show the recurrence of HFMD due to EV71 in Malaysia every 2 to 4 years. In each of the past outbreaks, more than one sub-genogroup of the virus co-circulate.展开更多
Objective:To investigate clinical and neuroimaging features of enterovirus71(EV71) related acute flaccid paralysis in patients with hand-fool-mouth disease.Methods:Nine patients with acute flaccid paralysis met the cr...Objective:To investigate clinical and neuroimaging features of enterovirus71(EV71) related acute flaccid paralysis in patients with hand-fool-mouth disease.Methods:Nine patients with acute flaccid paralysis met the criterion of EV71 induced hand-foot-mouth disease underwent spinal and brain MR imaging from May 2008 to Sep 2012.Results:One extremity flaccid was found in four cases(3 with lower limb,1 with upper limb),two limbs flaccid in three cases(2 with lower limbs,1 with upper limbs),and four limbs flaccid in two cases.Spinal MRI studies showed lesion with high signal in T2-weighted images(T2WI) and low signal T1-weighted images(T1WI) in the spinal cord of all nine cases,and the lesions were mainly in bilateral and unilateral anterior hom of cervical spinal cord and spinal cord below thoracic 9(T9) level.In addition,the midbrain,pons, and medulla,which were involved in 3 cases with brainstem encephalitis,demonstrated abnormal signal.Moreover,spinal cord contrast MRI studies showed mild enhancement in corresponding anterior hom of the involved side,and strong enhancement in its ventral root.Conclusions: EV71 related acute flaccid paralysis in patients with hand-foot-mouth disease mainly affected the anterior hom regions and ventral root of cervical spinal cord and spinal cord below T9 level. MR imaging could efficiendy show the characteristic pattern and extent of the lesions which correlated well with the clinical features.展开更多
Enterovirus 71(EV71) is one of the main pathogens that causes hand-foot-and-mouth disease(HFMD). HFMD caused by EV71 infection is mostly self-limited; however, some infections can cause severe neurological diseases, s...Enterovirus 71(EV71) is one of the main pathogens that causes hand-foot-and-mouth disease(HFMD). HFMD caused by EV71 infection is mostly self-limited; however, some infections can cause severe neurological diseases, such as aseptic meningitis, brain stem encephalitis, and even death. There are still no effective clinical drugs used for the prevention and treatment of HFMD. Studying EV71 protein function is essential for elucidating the EV71 replication process and developing anti-EV71 drugs and vaccines. In this review, we summarized the recent progress in the studies of EV71 noncoding regions(50 UTR and 30 UTR) and all structural and nonstructural proteins, especially the key motifs involving in viral infection, replication, and immune regulation. This review will promote our understanding of EV71 virus replication and pathogenesis, and will facilitate the development of novel drugs or vaccines to treat EV71.展开更多
Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic divers...Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic diversity of EV71, we determined and analyzed the complete VP1 sequences (891 nueleotides) from nine EV71 strains isolated in Fuyang, China. We found that nine EV71 strains isolated were over 98% homologous at the nucleotide level and 93%-100% homologous tO members of the C4 subgenogroup. At the amino acid level, these Fuyang strains were 99% -100% homologous to one another, 97%-100% homologous to members of the C4 subgenogroup, and the histidine(H) at amino acid position 22 was conserved among the Fuyang strains. The results indicate that Fuyang isolates belong to genotype C4, and an H at position 22 appears to be a marker for the Fuyang strains.展开更多
In order to realize simultaneous quantitative detection of various enteroviruses from water samples, a real-time reverse transcriptionpolymerase chain reaction (real-time RT-PCR) method was developed with universal ...In order to realize simultaneous quantitative detection of various enteroviruses from water samples, a real-time reverse transcriptionpolymerase chain reaction (real-time RT-PCR) method was developed with universal primer pairs designed based on the highly conserved non-coding region sequences of genome targeting poliovirus, coxsackievirus and enterovirus 71. The recombinant plasmid was constructed as enterovirus DNA standard by cloning poliovirus cDNA into a pMD18-T vector. The real-time RT-PCR method utilizing SYBR Green I was optimized. As a result of a series of examinations, the detection limit of the method was found to be 2.31 genome equivalent copy (GEC)/μL, the intraand inter-assay variations were lower than 2% and 5%, respectively, and enteroviruses were well distinguished from other microorganisms. There was a good linear relationship (r 2 = 0.997) between the logarithm of viral density and cycle threshold in a wide range of 2.31 × 10 0 to 2.31 × 10 9 GEC/μL. The validity of the method was further proved by its application for the detection of enteroviruses from various practical water samples.展开更多
AIM: To search for new antiviral agents from traditional Chinese medicine, specifically anti-enterovirosuses agents. METHODS: The aqueous extracts (AE) of more than 100 traditionally used medicinal plants in China...AIM: To search for new antiviral agents from traditional Chinese medicine, specifically anti-enterovirosuses agents. METHODS: The aqueous extracts (AE) of more than 100 traditionally used medicinal plants in China were evaluated for their in vitro anti-Coxsackie virus B3 activities with a MTT-based colorimetric assay. RESULTS: The test for AE of 16 plants exhibited anti- Coxsackie virus B3 activities at different magnitudes of potency. They can inhibit three steps (inactivation, adsorption and replication) during the infection. Among the 16 plants, Sargentodoxa cuneata (Oliv.) Rehd. et Wils., Sophora tonkinensis Gapnep., Paeonia veitchii Lynch, Spatholobus suberectus Dunn. and Cyrtorniurn fortunei J, sm. also have activity against other enterovirus, including Coxsackie virus 135, Polio virus I, Echo virus 9 and Echo virus 29. Cell cytotoxic assay demonstrated that all tested AE had CC50 values higher than their EC50 values. CONCLUSION: The sixteen traditionally used medicinal plants in China possessed antMral activity, and some of them merit further investigations.展开更多
Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontan...Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontaneously, include mucocutaneous papulovesicular lesions on the hands, feet, mouth, and buttocks. In rare cases, however, the patients may also develop neurological complications such as neurogenic pulmonary edema,展开更多
BACKGROUND Hand,foot,and mouth disease(HFMD)has become one of the most common infectious diseases in China.Before 2016,the primary causal serotypes were enterovirus A71(EV-A71)and coxsackievirus A16(CV-A16).Following ...BACKGROUND Hand,foot,and mouth disease(HFMD)has become one of the most common infectious diseases in China.Before 2016,the primary causal serotypes were enterovirus A71(EV-A71)and coxsackievirus A16(CV-A16).Following the introduction of EV-A71 vaccines in China since 2016,the situation could change.CV-A6 has recently replaced EV-A71 and CV-A16 in some areas of China.However,the epidemiological characteristics of central China remain unknown.AIM To investigate the clinical symptoms and pathogen spectrum of HFMD in Shiyan City,central China,in recent years.METHODS The epidemiological,clinical,and laboratory data from HFMD cases reported to the Shiyan Center for Disease Control and Prevention between January 2016 and December 2020 were analyzed.196 throat swab specimens were collected from hospitalized HFMD patients between January 2018 and December 2020.To detect and genotype enteroviruses,real-time reverse transcription-polymerase chain reaction and sequencing of the 5'-untranslated region were used.In Shiyan,168 laboratory-confirmed HFMD cases were studied using a logistic regression model to determine the effect of predominant enterovirus serotypes.Based on the logistic regression model,the least absolute shrinkage and selection operator model was used to analyze the correlation between CV-A6 infection and various clinical characteristics in HFMD patients in Shiyan.RESULTS From 2016 to 2020,35840 HFMD cases were reported in Shiyan.The number of cases decreased by 48.4%from 2016 to 2017.Approximately 1.58-fold increases were found in 2018 and 2019 when compared to the previous year,respectively.In 2020,a decrease of about 85.5%was reported when compared to 2019.The most common serotypes shifted from EV-A71 and CV-A16(about 60%-80%in 2016 and 2018)to others(more than 80.0%in 2017,2019,and 2020).EV-A71 lost its dominance in 2017 in Shiyan.Among 196 confirmed HFMD cases,85.7%tested positive for enterovirus,with CV-A6 being the most common serotype(121/168,72.0%).The positive rates for CV-A16 and CVA10 were 4.8%and 3.0%,respectively.There was no EV-A71 discovered.Infection with CV-A6 was linked to fever,myocardial damage,increased creatine kinase MB isoenzyme,and lactate dehydrogenase levels.CONCLUSION CV-A6 was the most common enterovirus serotype in Shiyan City,replacing EV-A71 and CV-A16 as the HFMD pathogen.Developing vaccines against CV-A6 or multiple pathogens,as well as rising CV-A6 surveillance,will help prevent HFMD in central China.展开更多
Human enterovirus 71 viruses have been long circulating throughout the world. In this study, we performed a positive selection analysis of the VP1 genes of capsid proteins from Enterovirus 71 viruses. Our results show...Human enterovirus 71 viruses have been long circulating throughout the world. In this study, we performed a positive selection analysis of the VP1 genes of capsid proteins from Enterovirus 71 viruses. Our results showed that although most sites were under negative or neutral evolution, four positions of the VP1 genes were under positive selection pressure. This might account for the spread and frequent outbreaks of the viruses and the enhanced neurovirulence. In particular, position 98 might be involved in neutralizing antibodies, modulating the virus-receptor interaction and enhancing the virulence of the viruses. Moreover, both positions 145 and 241 might correlate to determine the receptor specificity. However, these positions did not display much difference in amino acid polymorphism. In addition, no position in the VP1 genes of viruses isolated from China was under positive selection.展开更多
In this study,we have investigated the antiviral activity of GuiQi polysaccharides (GQP) upon enterovirus 71 (EV71) in vitro.An assay using methyl thiazolyl tetrazolium (MTT),and analyses of cytopathic effects (CPE)we...In this study,we have investigated the antiviral activity of GuiQi polysaccharides (GQP) upon enterovirus 71 (EV71) in vitro.An assay using methyl thiazolyl tetrazolium (MTT),and analyses of cytopathic effects (CPE)were used to examine the antiviral activity of GQP upon Vero cells infected with EV71.The results revealed that GQP at concentrations below 31.2μg/mL exhibited significant antiviral effects upon EV71 when applied under three different experimental protocols.GQP was most strongly active in preventing the adsorption of EV71 to target cells and in this respect it was significantly more effective than ribavirin.In addition,it was clear that GQP could inhibit viral replication when added to cells 2 h after infection,but if added at the point of infection its effect was weak.GQP is considered to be less toxic than ribavirin,and may warrant further evaluation as a possible agent in the treatment of hand,foot and mouth disease (HFMD).展开更多
Objective To develop RT-nPCR assays for amplifying partial and complete VP1 genes of human enteroviruses(HEVs)from clinical samples and to contribute to etiological surveillance of HEV-related diseases.Methods A panel...Objective To develop RT-nPCR assays for amplifying partial and complete VP1 genes of human enteroviruses(HEVs)from clinical samples and to contribute to etiological surveillance of HEV-related diseases.Methods A panel of RT-nPCR assays,consisting of published combined primer pairs for VP1 genes of HEV A–C and in-house designed primers for HEV-D,was established in this study.The sensitivity of each RT-nPCR assay was evaluated with serially diluted virus stocks of five serotypes expressed as CCID50 perμL and copies perμL,and the newly established methods were tested in clinical specimens collected in recent years.Results The sensitivity of RT-nPCR assays for amplifying partial VP1 gene of HEVs was 0.1 CCID50 perμL and 10 virus copies perμL,and for the complete VP1 gene was 1 CCID50 perμL and 100 virus copies perμL,using serially-diluted virus stocks of five serotypes.As a proof-of-concept,25 serotypes were identified and complete VP1 sequences of 23 serotypes were obtained by this system among 858 clinical specimens positive for HEVs during the past eight surveillance seasons.Conclusion This RT-nPCR system is capable of amplifying the partial and complete VP1 gene of HEV A–D,providing rapid,sensitive,and reliable options for molecular typing and molecular epidemiology of HEVs in clinical specimens.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
In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV7...In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster).展开更多
Enterovirus (EV71) can cause severe neurological diseases, but the underlying pathogenesis remains unclear. The capsid protein, viral protein 1 (VP1), plays a critical role in the pathogenicity of EVT1. High level...Enterovirus (EV71) can cause severe neurological diseases, but the underlying pathogenesis remains unclear. The capsid protein, viral protein 1 (VP1), plays a critical role in the pathogenicity of EVT1. High level expression and secretion ofVP 1 protein are necessary for structure, function and immunogenicity in its natural conformation. In our previous studies, 5 codon-optimized VP 1 DNA vaccines, including wt-VP 1, tPA-VP 1, VP l-d, VP 1-hFc and VP 1 - mFc, were constructed and analyzed. They expressed VP1 protein, but the levels of secretion and immunogenicity of these VP1 constructs were significantly different (P〈0.05). In this study, we further investigated the protein lev- els of these constructs and determined that all of these constructs expressed VP1 protein. The secretion level was increased by including a tPA leader sequence, which was further increased by fusing human IgG Fc (hFc) to VP1. VP 1-hFc demonstrated the most potent immunogenicity in mice. Furthermore, hFc domain could be used to purify VPI-hFc protein for additional studies.展开更多
Enterovirus D68(EV-D68)can cause respiratory diseases and acute flaccid paralysis,posing a great threat to public health.Interferons are cytokines secreted by host cells that have broad-spectrum antiviral effects,indu...Enterovirus D68(EV-D68)can cause respiratory diseases and acute flaccid paralysis,posing a great threat to public health.Interferons are cytokines secreted by host cells that have broad-spectrum antiviral effects,inducing the expression of hundreds of interferon-stimulated genes(ISGs).EV-D68 activates ISG expression early in infection,but at a later stage,the virus suppresses ISG expression,a strategy evolved by EV-D68 to antagonize interferons.Here,we explore a host protein,suppressor of cytokine signaling 3(SOCS3),is upregulated during EV-D68 infection and antagonizes the antiviral effects of type I interferon.We subsequently demonstrate that the structural protein of EV-D68 upregulated the expression of RFX7,a transcriptional regulator of SOCS3,leading to the upregulation of SOCS3 expression.Further exploration revealed that SOCS3 plays its role by inhibiting the phosphorylation of signal transducer and activator of transcription 3(STAT3).The expression of SOCS3 inhibited the expression of ISG,thereby inhibiting the antiviral effect of type I interferon and promoting EV-D68 transcription,protein production,and viral titer.Notably,a truncated SOCS3,generated by deleting the kinase inhibitory region(KIR)domain,failed to promote replication and translation of EV-D68.Based on the above studies,we designed a short peptide named SOCS3 inhibitor,which can specifically bind and inhibit the KIR structural domain of SOCS3,significantly reducing the RNA and protein levels of EV-D68.In summary,our results demonstrated a novel mechanism by which EV-D68 inhibits ISG transcription and antagonizes the antiviral responses of host type I interferon.展开更多
基金supported by the National Natural Science Foundation of China(31600139)the Chongqing Science and Technology Bureau(cstc2016jcyjA0020+3 种基金CSTB2024NSCQ-KJFZMSX0067)the Yuzhong District Science and Technology Commission(20190123)the Chongqing Municipal Education Commission(KJQN202300415)the Project of Undergraduates Innovating Experiment,and the Project of Tutorial System of Excellent Medical Undergraduates in the Lab Teaching and Management Center of Chongqing Medical University(S202410631068,LTMCMTS202458,LTMCMTS202459,LTMCMTS202460 and LTMCMTS202461).
文摘Enterovirus D68(EV-D68)and enterovirus A71(EV-A71)are two major types of enteroviruses that pose emerging challenges to public health and have the potential to cause outbreaks,yet their pathogenic mechanisms remain largely unexplored.Arrestin domain containing 3(ARRDC3)is a vital regulator of glucose metabolism,cancer development,and inflammation.Whether ARRDC3 contributes to innate antiviral immunity is undefined.Here,we found that enterovirus infection induces ARRDC3 expression at both the mRNA and protein levels,thereby inhibiting enterovirus replication.Moreover,we demonstrate that the expression of Yes-associated protein(YAP),a key effector of the Hippo pathway,is severely downregulated by ARRDC3 via lysosomal pathway.YAP facilitates enterovirus replication by suppressing the interferon pathway during the later stage of enterovirus infection,independent of its transcriptional activity.Finally,the ARRDC3-YAP pathway exhibits a broad-spectrum antiviral effect in various viral infections,including those caused by human parainfluenza virus type 3(HPIV3)and vesicular stomatitis virus(VSV).Collectively,our results identify the critical role of ARRDC3 and its negative regulatory effect on YAP in the innate antiviral response,suggesting a novel therapeutic strategy against virus infection.
基金supported by the National Natural Science Foundation of China(32200130 to Chong Wang and 82372228 to Yi Xu)the 2023-2024 Annual Scientific Research Project of Traditional Chinese Medicine from Hubei Provincial Administration of Traditional Chinese Medicine(ZY2023Q050 to Chong Wang)Hubei Province Natural Science Funds(2023AFA008 to Xi Zhou).
文摘Enterovirus A71(EV-A71)is the major causative pathogen for severe hand-foot-mouth disease(HFMD),a predominantly childhood-associated communicable disease.The mechanisms that children manifest severe disease progression while adults typically exhibit milder or asymptomatic infections remain incompletely characterized,which hinders the development of effective therapy against this disease.Herein,using the newborn mouse model of EV-A71 infection,we uncovered that the underdevelopment of T cells closely associated with the severity of EV-A71 infection,and EV-A71 infection dramatically impaired T-cell immune response.Moreover,the dysfunction of T-cell immunity contributes to the pathogenesis of EV-A71 infection,as the loss of T cells made neonatal mice highly vulnerable to EV-A71 infection.To further assess the relationship between T-cell immunity and HFMD,we enrolled a cohort of 145 pediatric patients with laboratory-confirmed EV-A71 infection and found that the compromised T-cell immune response is associated with the severity of EV-A71-caused HFMD in these children.Furthermore,we found that the treatment of newborn mice with Astragaloside A,a saponin from the medicinal herb Astragalus membranaceus,showed potent in vivo therapeutic efficacy against EV-A71 infection in a T-cell-dependent manner.In conclusion,these findings uncover the interaction between EV-A71 infection and T-cell immunity,provide novel insights onto the physiological impacts of T cells on the pathogenesis of EV-A71 infection and HFMD,and find a promising immunotherapeutic strategy to treat this viral disease.
基金supported by the National Science and Technology Major Project of China(No.2018ZX10201001-010,No.2017ZX10103009-005,No.2018ZX10713001-007)the National Natural Science Fund for Distinguished Young Scholars of China(No.81525023)+4 种基金the National Natural Science Foundation of China(No.81473031)the Program of Shanghai Academic/Technology Research Leader(No.18XD1400300)the Li Ka Shing Oxford Global Health Programme(No.B9RST00-B900.57)the Chinese Preventive Medicine Association(No:20101801)supported by CAS Pioneer Hundred Talents Program
文摘Enteroviruses(EVs)species A are a major public health issue in the Asia–Pacific region and cause frequent epidemics of hand,foot and mouth disease(HFMD)in China.Mild infections are common in children;however,HFMD can also cause severe illness that affects the central nervous system.To molecularly characterize EVs,a prospective HFMD virological surveillance program was performed in China between 2013 and 2016.Throat swabs,rectal swabs and stool samples were collected from suspected HFMD patients at participating hospitals.EVs were detected using generic real-time and nested reverse transcription-polymerase chain reactions(RT-PCRs).Then,the complete VP1 regions of enterovirus A71(EV-A71),coxsackievirus A16(CVA16)and CVA6 were sequenced to analyze amino acid changes and construct a viral molecular phylogeny.Of the 2836 enrolled HFMD patients,2,517(89%)were EV positive.The most frequently detected EVs were CVA16(32.5%,819),CVA6(31.2%,785),and EV-A71(20.4%,514).The subgenogroups CVA16B1 b,CVA6D3 a and EV-A71C4 a were predominant in China and recombination was not observed in the VP1 region.Sequence analysis revealed amino acid variations at the 30,29 and 44 positions in the VP1 region of EV-A71,CVA16 and CVA6(compared to the respective prototype strains Br Cr,G10 and Gdula),respectively.Furthermore,in 21 of 24(87.5%)identified EV-A71 samples,a known amino acid substitution(D31 N)that may enhance neurovirulence was detected.Our study provides insights about the genetic characteristics of common HFMD-associated EVs.However,the emergence and virulence of the described mutations require further investigation.
基金Supported by the National Science Council,No.93-2214-E-007-016 Ministry of Economic Affairs,No.93-EC-17A-17S1-0009
文摘AIM: Enterovirus 71 (EV71) has been implicated as the etiological agent responsible for the recent outbreaks of hand, foot and mouth disease associated with severe neurological diseases in the Asia-Pacific region. METHODS: The assembly process was hypothesized to occur via an orchestrated proteolytic processing of the P1 precursor by the viral protease 3CD. To test this hypothesis, we constructed 3 recombinant baculoviruses: Bac-P1 expressing P1; Bac-3CD expressing 3CD; and Bac-P1-3CD co-expressing P1 and 3CD. RESULTS: Both single infection by Bac-P1-3CD and coinfection by Bac-P1 and Bac-3CD resulted in correct cleavage of P1 to yield individual proteins VP0, VP1 and VP3, while the former approach yielded higher VLP production. In the cells, the structural proteins selfassembled into clusters of virus-like particles (VLP) resembling the authentic EV71 particle aggregates. After ultracentrifugation purification, the dispersed VLPs were indistinguishable from the authentic virus in size, appearance, composition and surface epitopes, as determined by SDS-PAGE, Western blot, transmission electron microscopy and immunogold labeling. CONCLUSION: Our data, for the first time, suggest that in insect cells EV71 structural proteins adopt a processing and assembly pathway similar to poliovirus assembly. The preservation of particle morphology and composition suggest that the VLP may be a valuable vaccine candidate to prevent EV71 epidemics.
基金supported by the TOTAL foundation,and the Grants from the National Science and Technology Major Project of China(2017ZX10103009-002)the "One Belt One Road" Project(153831KYSB20170043)of the Chinese Academy of Sciencesthe133 Project of Institut Pasteur of Shanghai,CAS.
文摘Hand, foot and mouth disease(HFMD) is a major public health concern in China. The most predominant enteroviruses that cause HFMD have traditionally been attributed to enterovirus A71(EVA71) and coxsackievirus A16(CVA16). Since its first large outbreak in 2008, the dominant HFMD pathogens are constantly changing. In 2013 and 2015, CVA6 exceeded both EVA71 and CVA16 to become the leading cause of HFMD in some provinces. However, there still lacks a comprehensive overview on the molecular epidemiology and evolution of HFMD-related enteroviruses at the national level. In this study, we performed systematic epidemiological analyses of HFMD-related enteroviruses using the data of 64 published papers that met the inclusion criteria, and conducted phylogenetic analyses based on 12,080 partial VP1 sequences identified in China before 31 st June 2018. We found that EVA71 prevalence has decreased sharply but other enteroviruses have increased rapidly from 2008 to 2016 and that one subtype of each enterovirus is represented during the epidemic. In addition, four genotypes EVA71_C4, CVA16_B1, CVA6_D and CVA10_C are the most predominant enterovirus strains and collectively they cause over 90% of all HFMD cases in China according to the phylogenetic trees using representative partial VP1 sequences. These four major enterovirus genotypes have different geographical distributions, and they may cocirculate with other genotypes and serotypes. These results suggest that more molecular epidemiological studies should be performed on several enteroviruses simultaneously, and such information should have implications for virological surveillance, disease management, vaccine development and policy-making on the prevention and control of HFMD.
文摘Hand foot and mouth disease is a febrile sickness complex characterized by cutaneous eruption (exanthem) on the palms and soles with simultaneous occurrence of muco-cutanous vesiculo-ulcerative lesions (enanthem) affecting the mouth. The illness is caused by a number of enteroviruses with coxsackievirus A16 and enterovirus 71 as the main causative agents. Human enterovirus 71 (EV71) belongs to the species Human enterovirus A under the genus Enterovirus within the family Picornaviridae. EV71 has been associated with an array of clinical diseases including hand foot and mouth disease (HFMD), aseptic meningitis, encephalitis and poliomyelitis-like acute flaccid paralysis. A large outbreak of HFMD due to highly neurovirulent EV71 emerged in Malaysia in 1997, and caused 41 deaths amongst young children. In late 2000, a recurrence of an outbreak of HFMD occurred in Malaysia with 8 fatalities in peninsular Malaysia. Outbreak of HFMD due to EV71 recurred in 2003 with an unknown number of cases and mortalities. A similar outbreak of HFMD with 2 recorded deaths in young children occurred in peninsular Malaysia in late 2005 and this was followed by a larger outbreak in Sarawak (Malaysian Borneo) with 6 reported fatalities in the early part of 2006. The current on-going outbreak of HFMD started in peninsular Malaysia in epidemiological week 12 of 2010. As with other HFMD outbreaks in Malaysia, both EV71 and CA16 were the main aetiological viruses isolated. In similarity with the HFMD outbreak in 2005, the isolation of CA16 preceded the appearance of EV71. Based on the VP1 gene nucleotide sequences, 4 sub-genogroups of EV71 (C1, C2, B3 and B4) co-circulated and caused the outbreak of hand, foot and mouth disease in peninsular Malaysia in 1997. Two sub-genogroups (C1 and B4) were noted to cause the outbreak in 2000 in both peninsular Malaysia and Sarawak. EV71 of sub-genogroup B5 with smaller contribution from sub-genogroup C1 caused the outbreak in 2003. In the 2005 outbreak, besides the EV71 strains of sub-genogroup C1, EV71 strains belonging to sub-genogroup B5 were isolated but formed a cluster which was distinct from the EV71 strains from the sub-genogroup B5 isolated in 2003. The four EV71 strains isolated from clinical specimens of patients with hand, foot and mouth disease in the Sarawak outbreak in early 2006 also belonged to sub-genogroup B5. Phylogenetic analysis of the VP1 gene suggests that the EV71 strains causing the outbreak in Sarawak could have originated from peninsular Malaysia. Epidemiological and molecular data since 1997 show the recurrence of HFMD due to EV71 in Malaysia every 2 to 4 years. In each of the past outbreaks, more than one sub-genogroup of the virus co-circulate.
基金funded by the Hainan Natural Science Foundation 310119Haiman Health Institution Project(No 2011-22)
文摘Objective:To investigate clinical and neuroimaging features of enterovirus71(EV71) related acute flaccid paralysis in patients with hand-fool-mouth disease.Methods:Nine patients with acute flaccid paralysis met the criterion of EV71 induced hand-foot-mouth disease underwent spinal and brain MR imaging from May 2008 to Sep 2012.Results:One extremity flaccid was found in four cases(3 with lower limb,1 with upper limb),two limbs flaccid in three cases(2 with lower limbs,1 with upper limbs),and four limbs flaccid in two cases.Spinal MRI studies showed lesion with high signal in T2-weighted images(T2WI) and low signal T1-weighted images(T1WI) in the spinal cord of all nine cases,and the lesions were mainly in bilateral and unilateral anterior hom of cervical spinal cord and spinal cord below thoracic 9(T9) level.In addition,the midbrain,pons, and medulla,which were involved in 3 cases with brainstem encephalitis,demonstrated abnormal signal.Moreover,spinal cord contrast MRI studies showed mild enhancement in corresponding anterior hom of the involved side,and strong enhancement in its ventral root.Conclusions: EV71 related acute flaccid paralysis in patients with hand-foot-mouth disease mainly affected the anterior hom regions and ventral root of cervical spinal cord and spinal cord below T9 level. MR imaging could efficiendy show the characteristic pattern and extent of the lesions which correlated well with the clinical features.
基金supported by the National Natural Science Foundation of China (Grant 81503118)CAMS Initiative for Innovative Medicine (CAMS-I2 M-1-010)The National Science and Technology Major Project of the Ministry of Science and Technology of China (2018ZX09711003-005-004)
文摘Enterovirus 71(EV71) is one of the main pathogens that causes hand-foot-and-mouth disease(HFMD). HFMD caused by EV71 infection is mostly self-limited; however, some infections can cause severe neurological diseases, such as aseptic meningitis, brain stem encephalitis, and even death. There are still no effective clinical drugs used for the prevention and treatment of HFMD. Studying EV71 protein function is essential for elucidating the EV71 replication process and developing anti-EV71 drugs and vaccines. In this review, we summarized the recent progress in the studies of EV71 noncoding regions(50 UTR and 30 UTR) and all structural and nonstructural proteins, especially the key motifs involving in viral infection, replication, and immune regulation. This review will promote our understanding of EV71 virus replication and pathogenesis, and will facilitate the development of novel drugs or vaccines to treat EV71.
基金Scientific Research Fund of Institute of Pathogen Biology(2008IPB108)
文摘Enterovirus 71 (EV71) is a common cause of Hand, foot, and mouth disease (HFMD) and may also cause severe neurological diseases, such as encephalitis and poliomyelitis-like paralysis. To examine the genetic diversity of EV71, we determined and analyzed the complete VP1 sequences (891 nueleotides) from nine EV71 strains isolated in Fuyang, China. We found that nine EV71 strains isolated were over 98% homologous at the nucleotide level and 93%-100% homologous tO members of the C4 subgenogroup. At the amino acid level, these Fuyang strains were 99% -100% homologous to one another, 97%-100% homologous to members of the C4 subgenogroup, and the histidine(H) at amino acid position 22 was conserved among the Fuyang strains. The results indicate that Fuyang isolates belong to genotype C4, and an H at position 22 appears to be a marker for the Fuyang strains.
基金supported by the National Natural Sci-ence Foundation of China (No. 50908185)the National Program of Water Pollution Control (No. 2008ZX07317-004)+2 种基金the Basic Research Foundation of Xi’an University of Architecture and Technology (No. JC0910)the Research Foundation for Talented Scholars of Xi’an University of Architecture and Technology (No. RC0824)the Program for Changjiang Scholars and Innovative Research Team in University (No. IRT0853)
文摘In order to realize simultaneous quantitative detection of various enteroviruses from water samples, a real-time reverse transcriptionpolymerase chain reaction (real-time RT-PCR) method was developed with universal primer pairs designed based on the highly conserved non-coding region sequences of genome targeting poliovirus, coxsackievirus and enterovirus 71. The recombinant plasmid was constructed as enterovirus DNA standard by cloning poliovirus cDNA into a pMD18-T vector. The real-time RT-PCR method utilizing SYBR Green I was optimized. As a result of a series of examinations, the detection limit of the method was found to be 2.31 genome equivalent copy (GEC)/μL, the intraand inter-assay variations were lower than 2% and 5%, respectively, and enteroviruses were well distinguished from other microorganisms. There was a good linear relationship (r 2 = 0.997) between the logarithm of viral density and cycle threshold in a wide range of 2.31 × 10 0 to 2.31 × 10 9 GEC/μL. The validity of the method was further proved by its application for the detection of enteroviruses from various practical water samples.
文摘AIM: To search for new antiviral agents from traditional Chinese medicine, specifically anti-enterovirosuses agents. METHODS: The aqueous extracts (AE) of more than 100 traditionally used medicinal plants in China were evaluated for their in vitro anti-Coxsackie virus B3 activities with a MTT-based colorimetric assay. RESULTS: The test for AE of 16 plants exhibited anti- Coxsackie virus B3 activities at different magnitudes of potency. They can inhibit three steps (inactivation, adsorption and replication) during the infection. Among the 16 plants, Sargentodoxa cuneata (Oliv.) Rehd. et Wils., Sophora tonkinensis Gapnep., Paeonia veitchii Lynch, Spatholobus suberectus Dunn. and Cyrtorniurn fortunei J, sm. also have activity against other enterovirus, including Coxsackie virus 135, Polio virus I, Echo virus 9 and Echo virus 29. Cell cytotoxic assay demonstrated that all tested AE had CC50 values higher than their EC50 values. CONCLUSION: The sixteen traditionally used medicinal plants in China possessed antMral activity, and some of them merit further investigations.
基金supported by National Foundation of China (project No.2013ZX10004-202)National Basic Research Program of China (973 Program,2011CB504902)National Natural Science Foundation of China (project Nos.30900063,81101303,81373049)
文摘Hand, foot, and mouth disease (HFMD) is a common contagious illness which occurs worldwide both sporadically and in epidemics. The disease mainly affects, children and the typical symptoms, which may resolve spontaneously, include mucocutaneous papulovesicular lesions on the hands, feet, mouth, and buttocks. In rare cases, however, the patients may also develop neurological complications such as neurogenic pulmonary edema,
基金Supported by the Hubei Province Health and Family Planning A Scientific Research Project,No.WJ2017M220the Wuhan Health Bureau Scientific Research Fund,No.WX19C11+2 种基金the Joint Precision Medical Research Fund From Taihe Hospital,No.2016JZ10the Shiyan COVID-19 Pilot Emergency Scientific Research Project,No.20Y19the Wuhan Children's Hospital Research Project,No.2017FE007.
文摘BACKGROUND Hand,foot,and mouth disease(HFMD)has become one of the most common infectious diseases in China.Before 2016,the primary causal serotypes were enterovirus A71(EV-A71)and coxsackievirus A16(CV-A16).Following the introduction of EV-A71 vaccines in China since 2016,the situation could change.CV-A6 has recently replaced EV-A71 and CV-A16 in some areas of China.However,the epidemiological characteristics of central China remain unknown.AIM To investigate the clinical symptoms and pathogen spectrum of HFMD in Shiyan City,central China,in recent years.METHODS The epidemiological,clinical,and laboratory data from HFMD cases reported to the Shiyan Center for Disease Control and Prevention between January 2016 and December 2020 were analyzed.196 throat swab specimens were collected from hospitalized HFMD patients between January 2018 and December 2020.To detect and genotype enteroviruses,real-time reverse transcription-polymerase chain reaction and sequencing of the 5'-untranslated region were used.In Shiyan,168 laboratory-confirmed HFMD cases were studied using a logistic regression model to determine the effect of predominant enterovirus serotypes.Based on the logistic regression model,the least absolute shrinkage and selection operator model was used to analyze the correlation between CV-A6 infection and various clinical characteristics in HFMD patients in Shiyan.RESULTS From 2016 to 2020,35840 HFMD cases were reported in Shiyan.The number of cases decreased by 48.4%from 2016 to 2017.Approximately 1.58-fold increases were found in 2018 and 2019 when compared to the previous year,respectively.In 2020,a decrease of about 85.5%was reported when compared to 2019.The most common serotypes shifted from EV-A71 and CV-A16(about 60%-80%in 2016 and 2018)to others(more than 80.0%in 2017,2019,and 2020).EV-A71 lost its dominance in 2017 in Shiyan.Among 196 confirmed HFMD cases,85.7%tested positive for enterovirus,with CV-A6 being the most common serotype(121/168,72.0%).The positive rates for CV-A16 and CVA10 were 4.8%and 3.0%,respectively.There was no EV-A71 discovered.Infection with CV-A6 was linked to fever,myocardial damage,increased creatine kinase MB isoenzyme,and lactate dehydrogenase levels.CONCLUSION CV-A6 was the most common enterovirus serotype in Shiyan City,replacing EV-A71 and CV-A16 as the HFMD pathogen.Developing vaccines against CV-A6 or multiple pathogens,as well as rising CV-A6 surveillance,will help prevent HFMD in central China.
文摘Human enterovirus 71 viruses have been long circulating throughout the world. In this study, we performed a positive selection analysis of the VP1 genes of capsid proteins from Enterovirus 71 viruses. Our results showed that although most sites were under negative or neutral evolution, four positions of the VP1 genes were under positive selection pressure. This might account for the spread and frequent outbreaks of the viruses and the enhanced neurovirulence. In particular, position 98 might be involved in neutralizing antibodies, modulating the virus-receptor interaction and enhancing the virulence of the viruses. Moreover, both positions 145 and 241 might correlate to determine the receptor specificity. However, these positions did not display much difference in amino acid polymorphism. In addition, no position in the VP1 genes of viruses isolated from China was under positive selection.
基金supported by research grants from The National Natural Science Foundation of China(NO81260070)The Project of Science and Technology of Lanzhou(NO 2011-1-71)The Doctor Project of Lanzhou University of Technology(NO 0908ZXC127)
文摘In this study,we have investigated the antiviral activity of GuiQi polysaccharides (GQP) upon enterovirus 71 (EV71) in vitro.An assay using methyl thiazolyl tetrazolium (MTT),and analyses of cytopathic effects (CPE)were used to examine the antiviral activity of GQP upon Vero cells infected with EV71.The results revealed that GQP at concentrations below 31.2μg/mL exhibited significant antiviral effects upon EV71 when applied under three different experimental protocols.GQP was most strongly active in preventing the adsorption of EV71 to target cells and in this respect it was significantly more effective than ribavirin.In addition,it was clear that GQP could inhibit viral replication when added to cells 2 h after infection,but if added at the point of infection its effect was weak.GQP is considered to be less toxic than ribavirin,and may warrant further evaluation as a possible agent in the treatment of hand,foot and mouth disease (HFMD).
基金National Science and Technology Major Projects[No.2017ZX10104001 and No.2017ZX10103008]Fujian Provincial Natural Science Foundation[No.2016J01350]。
文摘Objective To develop RT-nPCR assays for amplifying partial and complete VP1 genes of human enteroviruses(HEVs)from clinical samples and to contribute to etiological surveillance of HEV-related diseases.Methods A panel of RT-nPCR assays,consisting of published combined primer pairs for VP1 genes of HEV A–C and in-house designed primers for HEV-D,was established in this study.The sensitivity of each RT-nPCR assay was evaluated with serially diluted virus stocks of five serotypes expressed as CCID50 perμL and copies perμL,and the newly established methods were tested in clinical specimens collected in recent years.Results The sensitivity of RT-nPCR assays for amplifying partial VP1 gene of HEVs was 0.1 CCID50 perμL and 10 virus copies perμL,and for the complete VP1 gene was 1 CCID50 perμL and 100 virus copies perμL,using serially-diluted virus stocks of five serotypes.As a proof-of-concept,25 serotypes were identified and complete VP1 sequences of 23 serotypes were obtained by this system among 858 clinical specimens positive for HEVs during the past eight surveillance seasons.Conclusion This RT-nPCR system is capable of amplifying the partial and complete VP1 gene of HEV A–D,providing rapid,sensitive,and reliable options for molecular typing and molecular epidemiology of HEVs in clinical specimens.
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funded by Natural Science Foundation of Zhejiang(LQ14C010006)National Natural Science Foundation of China(81501363)Planned Science and Technology Project of Zhejiang(2014C33261)
文摘In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster).
基金supported by the National Natural Science Foundation of China(Grant No.81000725 and 31470889)the Priority Academic Program of Basic Medical Science of Nanjing Medical University(Grant No.JX10131801060)
文摘Enterovirus (EV71) can cause severe neurological diseases, but the underlying pathogenesis remains unclear. The capsid protein, viral protein 1 (VP1), plays a critical role in the pathogenicity of EVT1. High level expression and secretion ofVP 1 protein are necessary for structure, function and immunogenicity in its natural conformation. In our previous studies, 5 codon-optimized VP 1 DNA vaccines, including wt-VP 1, tPA-VP 1, VP l-d, VP 1-hFc and VP 1 - mFc, were constructed and analyzed. They expressed VP1 protein, but the levels of secretion and immunogenicity of these VP1 constructs were significantly different (P〈0.05). In this study, we further investigated the protein lev- els of these constructs and determined that all of these constructs expressed VP1 protein. The secretion level was increased by including a tPA leader sequence, which was further increased by fusing human IgG Fc (hFc) to VP1. VP 1-hFc demonstrated the most potent immunogenicity in mice. Furthermore, hFc domain could be used to purify VPI-hFc protein for additional studies.
基金This work was supported by the National Natural Science Foundation of China(32170144).
文摘Enterovirus D68(EV-D68)can cause respiratory diseases and acute flaccid paralysis,posing a great threat to public health.Interferons are cytokines secreted by host cells that have broad-spectrum antiviral effects,inducing the expression of hundreds of interferon-stimulated genes(ISGs).EV-D68 activates ISG expression early in infection,but at a later stage,the virus suppresses ISG expression,a strategy evolved by EV-D68 to antagonize interferons.Here,we explore a host protein,suppressor of cytokine signaling 3(SOCS3),is upregulated during EV-D68 infection and antagonizes the antiviral effects of type I interferon.We subsequently demonstrate that the structural protein of EV-D68 upregulated the expression of RFX7,a transcriptional regulator of SOCS3,leading to the upregulation of SOCS3 expression.Further exploration revealed that SOCS3 plays its role by inhibiting the phosphorylation of signal transducer and activator of transcription 3(STAT3).The expression of SOCS3 inhibited the expression of ISG,thereby inhibiting the antiviral effect of type I interferon and promoting EV-D68 transcription,protein production,and viral titer.Notably,a truncated SOCS3,generated by deleting the kinase inhibitory region(KIR)domain,failed to promote replication and translation of EV-D68.Based on the above studies,we designed a short peptide named SOCS3 inhibitor,which can specifically bind and inhibit the KIR structural domain of SOCS3,significantly reducing the RNA and protein levels of EV-D68.In summary,our results demonstrated a novel mechanism by which EV-D68 inhibits ISG transcription and antagonizes the antiviral responses of host type I interferon.