灰树花水溶物对EV71病毒的抑制作用

【目的】探讨灰树花水溶物(GFWE)的化学成分及其对EV71病毒的抑制作用,为促进灰树花综合利用、提高其经济附加值,以及开发预防和治疗EV71病毒感染的功能性食品提供依据。【方法】采用色谱法测定了GFWE的主要化学成分组成、多糖组成和分子质量。基于体外细胞培养采用CCK-8法确定了GFWE的安全上样量;以EV71病毒感染Vero细胞为模型,探究GFWE对EV71病毒的抑制率及对Vero细胞形态的影响,并采用荧光定量PCR检测了EV71病毒衣壳蛋白(VP1)编码基因mRNA的表达水平,初步评价了GFWE对EV71病毒的抑制作用。【结果】GFWE主要由低分子质量多糖、氨基酸、肽及其衍生物组成。GFWE富含的13种氨基酸中包含7种必需氨基酸;其多糖由葡萄糖、半乳糖、盐酸氨基葡萄糖和古罗糖醛酸4种单糖组成,物质的量比为0.907∶0.038∶0.029∶0.026,重均分子质量分别为15.67、10.10、6.60 ku和<1.00 ku。GFWE表现出较高的抗EV71病毒活性,100、200μg·mL^(-1) GFWE对EV71病毒的抑制率分别为91.32%、91.83%,25~400μg·mL^(-1) GFWE能显著降低EV71 VP1 mRNA的表达水平。【结论】GFWE主要由低分子质量多糖、氨基酸、肽及其衍生物组成,具有较高的抗EV71病毒活性,能够抑制感染EV71病毒的Vero细胞中VP1的合成。

Gp78 regulates PMP22 and causes ER stress and autophagy in EV71-VP1-overexpressing mouse Schwann cells

Background:During Enterovirus type 71(EV71)infection,the structural viral protein 1(VP1)activates endoplasmic reticulum(ER)stress associated with peripheral myelin protein 22(PMP22)accumulation and induces autophagy.However,the specific mechanism behind this process remains elusive.Methods:In this research,we used the VP1-overexpressing mouse Schwann cells(SCs)models co-transfected with a PMP22 silencing or Autocrine motility factor receptor(AMFR/gp78)overexpressing vector to explore the regulation of gp78 on PMP22 and its relationship with autophagy and apoptosis.Results:The activity of gp78 could be influenced by EV71-VP1,leading to a decrease in the ubiquitination and degradation of PMP22,resulting in PMP22 accumulation in ER.In VP1-overexpressing mouse SCs,all three ER stress sensors,including pancreatic endoplasmic reticulum kinase(PERK),activating transcription factor 6(ATF6)and inositol-requiring enzyme 1(IRE1)and the related downstream signals(C/EBP-homologous protein(CHOP)and Caspase 12)were activated,as well as the ER-resident chaperone Glucose-regulated protein 78(GRP78).In addition,VP1 upregulated the autophagy marker Microtubule-associated protein 1 light chain 3 beta(LC3B),while PMP22 silencing or gp78 overexpression reversed the phenomenon.Meanwhile,PMP22 silencing or gp78 overexpression increased proliferation of EV71-VP1-transfected mouse SCs.Conclusion:Gp78 could regulate PMP22 accumulation through ubiquitination degradation and cause ER stress and autophagy in EV71-VP1-overexpressing mouse SCs.Therefore,the gp78/PMP22/ER stress axis might emerge as a promising therapeutic target for myelin and neuronal damage induced by EV71 infection.

CD25基因多态性与EV71感染手足口病患儿易感性及严重性的关系

目的:探讨CD25基因多态性与肠道病毒71型(EV71)感染手足口病(HFMD)患儿易感性及严重性的关系。方法:将2020年11月—2022年11月我院收治的122例EV71感染HFMD患儿作为本次研究对象(HFMD组),根据疾病严重程度分为轻症组(n=79)和重症组(n=43)2个亚组。另外将同时期在我院进行健康检查的150例健康儿童纳入对照组。采用限制性片段长度多态性聚合酶链反应(PCR-RFLP)技术鉴定CD25基因rs7072793位点基因分型;采用Hardy-Weinberg遗传平衡度检验对样本代表性进行评估;采用多因素Logistic回归分析探讨EV71感染重症HFMD发病的危险因素。结果:对照组和HFMD组CD25基因rs7072793位点基因型符合Hardy-Weinberg遗传平衡定律,样本具有代表性(P>0.05)。对照组CD25基因rs7072793位点CC、CT、TT基因型频率和C、T等位基因频率与HFMD组比较,差异有统计学意义(P<0.05)。轻症组CD25基因rs7072793位点CC、CT、TT基因型频率和C、T等位基因频率与重症组比较,差异有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,脑电图结果异常、CD25基因rs7072793位点TT基因型、CD25基因rs7072793位点T等位基因是EV71感染重症HFMD发病的独立危险因素(P<0.05)。结论:CD25基因rs7072793位点多态性与EV71感染HFMD患儿的易感风险和病情严重程度存在关联,且携带TT基因型、T等位基因患儿进展为重症的风险更高。

儿童清咽解热口服液体外抗肠道病毒71型作用

目的 研究儿童清咽解热口服液体外抗肠道病毒71型(EV71)的作用。方法 以盐酸胍为阳性对照,在Vero-E6细胞水平上,采用CellTiter-GloTM测定受试样品的细胞毒性,采用间接免疫荧光法测定肠道病毒蛋白表达水平,评价儿童清咽解热口服液对EV71的抗病毒作用。结果 儿童清咽解热口服液对Vero-E6细胞的半数毒性浓度为127.2mg/ml,抑制EV71病毒复制的半数有效浓度为3.193mg/ml,选择指数为39.8。结论 在Vero-E6细胞水平上,儿童清咽解热口服液对EV71具有明显的抗病毒作用。

HPLC-UV法检测EV71-CA16二价手足口病灭活疫苗原液相关抗原纯度的方法建立与评价

为建立一种准确可靠的高效液相色谱-紫外(HPLC-UV)方法,检测EV71-CA16二价手足口病(HFMD)灭活疫苗原液中的相关抗原,肠道病毒71型(EV71)和柯萨奇病毒A组16型(CA16)的纯度。本文采用Waters体积排阻色谱柱(SEC,UltrahydrogelTM 2507.8×300 mm,6μm),流动相为0.01 mol/L的PBS中再加入0.1 mol/L氯化钠溶液,等度洗脱,流速0.3 mL/min,检测波长280 nm,进样量50μL,柱温21℃,进行EV71与CA16病毒原液的纯度检测,并对该方法的检测限、拖尾因子、专属性、重复性及检测范围进行验证。结果显示,2种抗原的灵敏度溶液的信噪比(S/N)分别为37.053和47.710,均远大于3,各试样的拖尾因子均小于3;CA16原液和EV71原液经HPLC分离纯化后的目标抗原峰馏分经SDS-PAGE和Western-Blot特异性鉴定,结果显示,色谱峰样品组成分别为CA16和EV71的2种病毒衣壳的结构蛋白,表明本检测方法专属性高。不同浓度的EV71与CA16病毒抗原经多次检测后,各浓度条件下的峰面积百分比与保留时间的RSD均小于1%,重复性良好。不同抗原浓度批样品检测结果显示,CA16原液抗原浓度在89 U/mL~26398 U/mL之间,EV71原液抗原浓度在170 U/mL~9074 U/mL之间时,2种抗原溶液经多次检测统计显示峰面积百分比与保留时间的RSD均小于1%,本方法在该抗原浓度范围内准确可靠,适用于EV71-CA16二价手足口病灭活疫苗原液中病毒抗原纯度的检测。

Hand Foot and Mouth Disease Due to Enterovirus 71 in Malaysia

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.

Genetic Analysis of the VP1 Region of Human Enterovirus 71 Strains Isolated in Fuyang,China,During 2008

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 nucleotides) 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.

Expression,purification and characterization of enterovirus-71 virus-like particles

瞄准：Enterovirus 71 (EV71 ) 作为为在亚太区域与严重神经病学的疾病联系的手，脚和嘴疾病的最近的爆发负责的病因学的代理人被含有。方法：集会过程被假设发生经由一由病毒的朊酶 3CD 的 P1 先锋的安排解朊的处理。测试这个假设，我们构造了 3 recombinant baculoviruses：表示 P1 的 Bac-P1；表示 3CD 的 Bac-3CD；并且 Bac-P1-3CD 共同表示 P1 和 3CD。结果：由 Bac-P1-3CD 的两单个感染和由 Bac-P1 和 Bac-3CD 的合作感染导致了 P1 的正确劈开产出单个蛋白质 VP0， VP1 和 VP3，当以前的途径产出更高的 VLP 生产时。在房间，进类似于真 EV71 粒子总数的像病毒的粒子(VLP ) 的簇自我装配的结构的蛋白质。在 ultracentrifugation 纯化以后，驱散的 VLP 与在尺寸，外观，作文和表面 epitopes 的真病毒难区分，作为由标记的 SDS 页，西方的污点，传播电子显微镜学和免疫黄金决定了。结论：我们的数据第一次，在 EV71 结构的蛋白质采用一个处理和类似于脊髓灰质炎病毒汇编的汇编小径的昆虫房间建议那。粒子形态学和作文的保藏建议 VLP 可以是一个珍贵疫苗的候选人阻止 EV71 流行病。

Human IgG Fc promotes expression, secretion and immunogenicity of enterovirus 71 VP1 protein

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.

Therapeutic and prevention strategies against human enterovirus 71 infection

Human enterovirus 71(HEV71) is the cause of hand,foot and mouth disease and associated neurological complications in children under five years of age.There has been an increase in HEV71 epidemic activity throughout the Asia-Pacific region in the past decade,and it is predicted to replace poliovirus as the extant neurotropic enterovirus of highest global public health significance. To date there is no effective antiviral treatment and no vaccine is available to prevent HEV71 infection. The increase in prevalence, virulence and geographic spread of HEV71 infection over the past decade provides increasing incentive for the development of new therapeutic and prevention strategies against this emerging viral infection. The current review focuses on the potential, advantages and disadvantages of these strategies. Since the explosion of outbreaks leading to large epidemics in China, research in natural therapeutic products has identified several groups of compounds with anti-HEV71 activities. Concurrently, the search for effective synthetic antivirals has produced promising results. Other therapeutic strategies including immunotherapy and the use of oligonucleotides have also been explored. A sound prevention strategy is crucial in order to control the spread of HEV71. To this end the ultimate goal is the rapid development, regulatory approval and widespread implementation of a safe and effective vaccine. The various forms of HEV71 vaccine designs are highlighted in this review. Given the rapid progress of research in this area, eradication of the virus is likely to be achieved.

Evaluation of Reverse Transcription Loop-Mediated Isothermal Amplification assays for Rapid Detection of Human Enterovirus 71 and Coxsackievirus A16 in Clinical Samples

A sensitive reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for human enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16) infection was further evaluated. The one step reaction was performed in a single tube at 65?C for 45 min for EV71 and 35 min for CVA16. The detection limits of RT-LAMP assays for both EV71 and CVA16 were 0.1 of a 50% tissue culture infective dose (TCID50) per reaction, based on 10—Fold dilutions of a titrated EV71 or CVA16 strain. The specific assay showed there were no cross-reactions with Coxsackievirus A (CVA) viruses (CVA 2, 4, 5, 7, 9, 10, 14, and 25), Coxsackievirus B (CVB) viruses (CVB 1, 2, 3, 4, and 5) or ECHO viruses (ECHO 3, 6, 11, and 19). In parallel with commercial quantitative real-time polymerase chain reaction (qRT-PCR) diagnostic kits for EV71 and CVA16, the RT-LAMP assay was evaluated with 515 clinical specimens, the results showed the RT-LAMP assay and the qRT-PCR assay were in complete agreement for 513/515 (99.6%) of the specimens. Two samples with discrepant results from two methods were further verified by nested reverse transcription polymerase chain reaction (nRT-PCR) assay and sequencing to be true positives for CVA16. In conclusion, RT-LAMP assay is demonstrated to be a sensitive and specific assay and have a great potential for the rapid and visual screening of EV71 and CVA16 in China, especially in those resource-limited hospitals and rural clinics of provincial and municipal regions.

Positive Selection Analysis of VP1 Genes of Worldwide Human Enterovirus 71 Viruses

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.

Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites

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）.

Antiviral Activity of GuiQi Polysaccharides against Enterovirus 71 in vitro

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).

Pancreatitis in hand-foot-and-mouth disease caused byenterovirus 71

Some viruses, including certain members of the enterovirus genus, have been reported to cause pancreatitis, especially Coxsackie virus. However, no case of human enterovirus 71(EV71) associated with pancreatitis has been reported so far. We here report a case of EV71-induced hand-foot-and-mouth disease(HFMD) presenting with pancreatitis in a 2-year-old girl. This is the first report of a patient with acute pancreatitis in HFMD caused by EV71. We treated the patient conservatively with nasogastric suction, intravenous fluid and antivirals. The patient's symptoms improved after 8 d, and recovered without complications. We conclude that EV71 can cause acute pancreatitis in HFMD, which should be considered in differential diagnosis, especially in cases of idiopathic pancreatitis.

Viral kinetics of Enterovirus 71 in human habdomyosarcoma cells

AIM:To characterise the viral kinetics of enterovirus 71 (EV71).METHODS:In this study,human rhabdomyosarcoma (RD) cells were infected with EV71 at different multiplicity of infection (MOI).After infection,the cytopathic effect (CPE) was monitored and recorded using a phase contrast microscope associated with a CCD camera at different time points post viral infection (0,6,12,24 h post infection).Cell growth and viability were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in both EV71 infected and mock infected cells at each time point.EV71 replication kinet-ics in RD cells was determined by measuring the total intracellular viral RNA with real-time reverse-transcription polymerase chain reaction (qRT-PCR).Also,the intracellular and extracellular virion RNA was isolated and quantified at different time points to analyze the viral package and secretion.The expression of viral protein was determined by analyze the levels of viral structure protein VP1 with Western blotting.RESULTS:EV71 infection induced a significant CPE as early as 6 h post infection (p.i.) in both RD cells infected with high ratio of virus (MOI 10) and low ratio of virus (MOI 1).In EV71 infected cells,the cell growth was inhibited and the number of viable cells was rapidly decreased in the later phase of infection.EV71 virions were uncoated immediately after entry.The intracellular viral RNA began to increase at as early as 3 h p.i.and the exponential increase was found between 3 h to 6 h p.i.in both infected groups.For viral structure protein synthesis,results from western-blot showed that intracellular viral protein VP1 could not be detected until 6 h p.i.in the cells infected at either MOI 1 or MOI 10;and reached the peak at 9 h p.i.in the cells infected with EV71 at both MOI 1 and MOI 10.Simultaneously,the viral package and secretion were also actively processed as the virus underwent rapid replication.The viral package kinetics was comparable for both MOI 1 and MOI 10 infected groups.It was observed that at 3 h p.i,the intracellular virions obviously decreased,thereafter,the intracellular virions began to increase and enter into the exponential phase until 12 h p.i.The total amounts of intracellular virons were decreased from 12 to 24 h p.i.Consistent with this result,the increase of virus secretion occurred during 6 to 12 h p.i.CONCLUSION:The viral kinetics of EV71 were established by analyzing viral replication,package and secretion in RD cells.

Safe and Objective Assay of Enterovirus 71 Neutralizing Antibodies via Pseudovirus

Current serum neutralization assays based on the inhibition of the cytopathic effect（Nt-CPE） need to ma nipulate live viruses, which are time-consuming, labor-intensive, and have the potential exposure to infectious agents, so a safe and objective assay via pseudovirus for the fast and efficient detection of enterovirus 71（EV71） neutralizing antibodies was developed. First, we generated EV71 pseudovirus containing firefly luciferase gene in place of the capsid gene P1 in EV71 genome. Vero cells infected with 200 CCID50（50% cell culture infective dose） of EV71 pseudovirus for 24 h were found to have the best performance. Seval sera were measured by EV71 pseudoparticle neutralization assay（Nt-PPN） and the conventional serological method Nt-CPE. Neutralizing antibody titers measured by Nt-PPN and those obtained by Nt-CPE demonstrate a high correlation between the two methods. Overall, the PPN assay represents a valid alternative to conventional serological methods for the evaluation of EV71 neutralizing anti bodies. This method can be used for detecting neutralizing antibodies of other picornaviruses, such as hepatitis A vi rus（HAV） and coxsackievirus 16（CVA16）, and make it possible to determine whether there is cross-reactivity be tween EV71 and CVA16.

Human Enterovirus 71 DNA Vaccine Constructs Containing 5’UTR with Complete Internal Ribosome Entry Site Sequence Stimulated Improved Anti-Human Enterovirus 71 Neutralizing Immune Responses

Recent improvement in the technologies for efficient delivery of DNA vaccines has renewed interest in the DNA-based vaccines. Several DNA-based vaccines against human enterovirus 71 (EV71), the causative agent for hand, foot and mouth disease (HFMD) have been developed. Here we examined the potential of improving the vaccines by inserting the EV71 5’ untranslated region (5’ UTR) containing the full length internal ribosome entry site (IRES) sequence to the EV71 VP1-based DNA vaccine constructs. Four vaccine constructs designated as 5’ UTR-VP1/EGFP, VP1/EGFP, 5’ UTR-VP1/pVAX and VP1/pVAX, were designed using the pEGFP-N1 and pVAX-1 expression vectors, respectively. Transfection of Vero cells with the vaccine constructs with the 5’-UTR (5’-UTR-VP1/EGFP and 5’ UTR-VP1/pVAX) resulted in higher percentages of cells expressing the recombinant protein in comparison to cells transfected with vectors without the 5’-UTR (67% and 57%, respectively). Higher IgG responses (29%) were obtained from mice immunized with the DNA vaccine construct with the full length 5’ UTR. The same group of mice when challenged with life EV71 produced significantly higher neutralizing antibody (NAb) titers (>5-fold). These results suggest that insertion of the EV71 5’ UTR sequence consisting of the full length IRES to the EV71 DNA vaccine constructs improved the efficacy of the constructs with enhanced elicitation of the neutralizing antibody responses.

Contribution of 3CD Region to the Virulence of Enterovirus 71

Enterovirus 71 （EV71） and Coxsackievirus A16 （CoxA16） are the major pathogens causing hand, foot, and mouth disease （HFMD） that occurs primarily in children and infants with mild clinical manifestations. HFMD caused by EV71 could develop to a fatal neurological complication.

A Novel Pharmacophore Model Derived from a Class of Capsid Protein Enterovirus 71 Inhibitors

Capsid protein enterovirus 71 （EV71） is one of the major viruses that cause the severe encephalitis and thus result in a high mortality in children less than 5 years of age.In an effort to discover new potent inhibitors against EV71,a novel three-dimensional pharmacophore model was developed on 24 inhibitors with different molecular structures and bioactivities.The best hypothesis （Hypo1） has a high predictive power and consists of four features,namely,one hydrophobic point （HY） and three hydrogen-bond acceptors （HA）.Two key features of the best Hypo1,HY1 and HA3 match well with an important narrow hydrophobic canyon and with the surface of LYS274 in the target EV71 active site,respectively.The more versatile feature,HA1,is firstly found to be very influential on these compounds’ bioactivities,which may interact with the other side of the active site in the EV71 receptor.The application of the model is successful in predicting the activities of 30 known EV71 inhibitors with a correlation coefficient of 0.831.Furthermore,Hypo1 demonstrates a superior screening capability for retrieving inhibitors from the database with a high enrichment factor of 70.This study provides some important clues in search for more potent inhibitors against EV71 infection.