共查询到20条相似文献，搜索用时 12 毫秒
1.
Zhi‐Hui Li Ying‐Ying Yue Peng Li Nan‐Nan Song Bingqing Li Ying Zhang Hong Meng Guo‐Sheng Jiang Lizeng Qin 《Microbiology and immunology》2015,59(8):477-482
Enterovirus A71 (EV‐A71), one of the most important causative agents of hand, foot and mouth disease (HFMD) in children, can lead to severe clinical outcomes, even death. However, the infection spectrum of EV‐A71 in different cell lines remains unknown. Therefore, in this study, the biological characteristics of EV‐A71 Subgroup C4 in different cell lines were investigated. To this end, the infectivity of EV‐A71Jinan1002 isolated from children with severe HFMD was assessed in 18 different host cell lines. It was found that the MA104 cell line displayed biological characteristics suitable for EV‐A71 Subgroup C4 strain isolation and proliferation; indeed, it was found that a broad spectrum of cell lines can be infected by EV‐A71Jinan1002. Among the screened cells, four cell lines (HEK293, RD, MA104 and Marc145) produced high 50% tissue culture infective dose (TCID50) values calculated in viral proliferations (ranged from 107.6 to 107.8); the TCID50 being negatively associated with the time to appearance of CPE. Proliferation curves demonstrated that EV‐A71Jinan1002 amplifies more efficiently in MA104, Hep‐2 and RD cells. Remarkably, the virus isolation rate was much higher in MA104 cells than in RD cells. Thus this study, to our knowledge, is for the first to explore the infection spectrum of EV‐A71 subgroup C4 in such a large number of different cell lines. Our data provide useful reference data for facilitating further study of EV‐A71. 相似文献
2.
Xuyuan Zhang Pan Yang Nan Wang Jialong Zhang Jingyun Li Hao Guo Xiangyun Yin Zihe Rao Xiangxi Wang Liguo Zhang 《蛋白质与细胞》2017,8(8):590-600
Entero virus 71 (EV71) causes hand, foot, and mouth disease (HFMD) and occasionally leads to severe neurological complications and even death. Scavenger receptor class B member 2 (SCARB2) is a functional receptor for EV71, that mediates viral attachment, internalization, and uncoating. However, the exact binding site of EV71 on SCARB2 is unknown. In this study, we generated a monoclonal antibody (mAb) that binds to human but not mouse SCARB2. It is named JL2, and it can effectively inhibit EV71 infection of target cells. Using a set of chimeras of human and mouse SCARB2, we identified that the region containing residues 77-113 of human SCARB2 contributes significantly to JL2 binding. The structure of the SCARB2-JL2 complex revealed that JL2 binds to the apical region of SCARB2 involving α-helices 2, 5, and 14. Our results provide new insights into the potential binding sites for EV71 on SCARB2 and the molecular mechanism of EV71 entry. 相似文献
3.
Sekiguchi F Ohi A Maeda Y Takaoka K Sekimoto T Nishikawa H Kawabata A 《Journal of cellular biochemistry》2011,112(3):909-915
Proteinase-activated receptor-1 (PAR1), upon activation, exerts prostanoid-dependent gastroprotection, and increases prostaglandin E(2) (PGE(2)) release through cyclooxygenase-2 (COX-2) upregulation in rat gastric mucosal epithelial RGM1 cells. However, there is a big time lag between the PAR1-triggered PGE(2) release and COX-2 upregulation in RGM1 cells; that is, the former event takes 18 h to occur, while the latter rapidly develops and reaches a plateau in 6 h. The present study thus aimed at clarifying mechanisms for the delay of PGE(2) release after PAR1 activation in RGM1 cells. Although a PAR1-activating peptide, TFLLR-NH(2), alone caused PGE(2) release at 18 h, but not 6 h, TFLLR-NH(2) in combination with arachidonic acid dramatically enhanced PGE(2) release even for 1-6 h. TFLLR-NH(2) plus linoleic acid caused a similar rapid response. CP-24879, a Δ(5)/Δ(6)-desaturase inhibitor, abolished the PGE(2) release induced by TFLLR-NH(2) plus linoleic acid, but not by TFLLR-NH(2) alone. The TFLLR-NH(2)-induced PGE(2) release was not affected by inhibitors of cytosolic phospholipase A(2) (cPLA(2)), Ca(2+)-independent PLA(2) (cPLA(2)) or secretory PLA(2) (sPLA(2)), but was abolished by their mixture or a pan-PLA(2) inhibitor. Among PLA(2) isozymes, mRNA of group IIA sPLA(2) (sPLA(2)-IIA) was upregulated following PAR1 stimulation for 6-18 h, whereas protein levels of PGE synthases were unchanged. These data suggest that the delay of PGE(2) release after COX-2 upregulation triggered by PAR1 is due to the poor supply of free arachidonic acid at the early stage in RGM1 cells, and that plural isozymes of PLA(2) including sPLA(2)-IIA may complementarily contribute to the liberation of free arachidonic acid. 相似文献
4.
5.
Gall L Chene N Dahirel M Ruffini S Boulesteix C 《Molecular reproduction and development》2004,67(4):439-445
6.
EGF has been shown to influence meiotic maturation and development competence of oocyte in various mammalian species. We previously reported, in goat, that the EGF receptor (EGF-R) was present both on cumulus cells and oocytes. Here, EGF-induced signaling was investigated during the in vitro maturation process in goat cumulus-oocyte complexes (COCs). Cumulus cells and oocytes were subjected to Western immunoblotting analysis using anti-MAP kinase, anti-phosphotyrosine, anti-phospho MAP kinase, and anti-phospho EGF-R antibodies. We demonstrated that treatment with EGF during the in vitro maturation process induced rapid tyrosine phosphorylation of EGF-R in a time and concentration dependent manner in cumulus cells. A similar pattern of activation by phosphorylation was observed for MAP kinase upon EGF stimulation. AG 1478, an inhibitor of the EGF kinase, suppressed EGF-stimulated phosphorylation of EGF-R and also affected the MAP kinase activation. Treatment with the MEK inhibitor PD 98059 abolished EGF-induced MAP kinase activation. We did not observe oocyte EGF-R phosphorylation in our experiments during the in vitro maturation process. Our data indicate, in goat cumulus cells, that activation of EGF-R by EGF triggers signaling through the MAP kinase pathway during in vitro maturation. This supports the hypothesis that the major site of action for EGF, that regulates oocyte maturation, is the cumulus cell. 相似文献
7.
Song Yub Shin Tetsuo Yokoyama Takato Takenouchi Eisuke Munekata 《Journal of peptide science》2003,9(4):244-250
Heparin-binding EGF-like growth factor (HB-EGF), which belongs to the EGF-family of growth factors, was isolated from the conditioned medium of macrophage-like cells. To investigate the effect of N- and C-terminal residues of the EGF-like domain of HB-EGF in the binding affinity to the EGF receptor on A431 cell. We synthesized HB-EGF(44-86) corresponding to the EGF-like domain of HB-EGF and its N- or C-terminal truncated peptides. Thermolytic digestion demonstrated three disulfide bond pairings of the EGF-like domain in HB-EGF is consistent with that of human-EGF and human-TGF-alpha. HB-EGF(44-86) showed high binding affinity to EGF-receptor, like human-EGF. The truncation of the C-terminal Leu86 residue from HB-EGF(44-86), HB-EGF(45-86) or HB-EGF(46-86) caused a drastic reduction in the binding affinity to the EGF receptor. These results suggest that the EGF-like domain of HB-EGF plays an important role in the binding to the EGF receptor, and its C-terminal Leu86 residue is necessary for binding with the EGF-receptor. In addition, the deletion of the two N-terminal residues (Asp44-Pro45) from HB-EGF(44-86) caused a 10-fold decrease in relative binding affinity to the EGF receptor. This indicates that the two N-terminal residues of the EGF-like domain of HB-EGF are necessary for its optimal binding affinity to the EGF receptor. 相似文献
8.
The presence of EGF- and EGF-receptor-like immunoreactivity in Tetrahymena was studied with the help of FITC-labelled monoclonal antibodies, using flow cytometry and confocal microscopy. Tetrahymena has endogeneous EGF and treatment with it significantly increases the hormone content of the cells. The hormone is diffusely localized, particularly in the cytopharynx, where it forms a structure larger than 10 microm. EGF-receptors are also demonstrable, particularly in the cortical region in connection with cilia, and EGF treatment significantly enhances cortical fluorescence. The relationships between these observations and literary data on the effects of EGF in Tetrahymena are discussed. 相似文献
9.
目的用1日龄ICR小鼠传代制备EV71小鼠适应株,研究EV71亲代株与小鼠适应株的体内外感染特点,建立EV71感染ICR小鼠动物模型,为病毒疫苗和抗病毒药物的研究提供实用的动物评价工具。方法用1日龄ICR小鼠进行EV71病毒(Fuyang-0805)的传代,得到小鼠传代株。以一定浓度亲代株和传代株病毒分别接种RD、Vero、SY5Y、Caco-2四种细胞,定量方法检测各时间点不同毒株在四种细胞上的复制数量,CCK8方法测定各时间点细胞的存活率;同时,两毒株分别腹腔注射感染1日龄小鼠,定期安乐死动物,采集肺、小肠、骨骼肌、大脑四种器官组织,进行动物体内病毒半定量和定量分析,同时进行各器官组织病理学观察、免疫组织化学鉴定。结果与亲代毒株相比较,小鼠传代株(EV71-MMP4)表现出更强的肌肉来源细胞嗜性与毒性;同时,两毒株腹腔注射感染1日龄小鼠后,EV71-MMP4感染的小鼠体重增长较正常小鼠体重增长缓慢;半定量和定量RT-PCR显示,在小鼠肌肉中的病毒载量于感染后1d和5d达到高峰。EV71-MMP4感染组感染率较高、病毒组织分布较广、感染持续性较好、病毒载量较高,高剂量病毒感染后小鼠小肠、心肌和骨骼肌可观察到细胞空泡变性、淋巴细胞浸润等病理变化。免疫组织化学显示感染后小鼠骨骼肌有EV71病毒特异分布。结论阜阳EV71小鼠适应株表现出较亲代毒株更好的小鼠易感性、细胞毒性,所建立的动物模型可用于EV71病毒致病机制、感染特点的研究和病毒疫苗及药物的评价。 相似文献
10.
11.
Qingzhan Yang Qing Jie Neil Shaw Lei Li Zihe Rao Zheng Yin Zhiyong Lou 《International journal of biological sciences》2015,11(11):1337-1347
In recent years, hand-foot-and-mouth disease (HFMD), which is caused by Enteroviruses, has emerged as a serious illness. It affects mainly children under the age of five and results in high fatality rates. Enterovirus 71 (EV71) is the main causative agent of HFMD in China and currently there are no effective anti-viral drugs available to treat HFMD. In the present study, we screened compounds for inhibition of proliferation of EV71. Compound YZ-LY-0 stalled the life cycle of EV71. The inhibitor exhibited EC50 value of 0.29 μm against SK-EV006 strain of EV71. Notably, YZ-LY-0 had low cytotoxicity (CC50 > 100 μM) and a high selectivity index (over 300) in Vero and RD cells. YZ-LY-0 in combination with an EV71 RdRp inhibitor or an entry inhibitor showed an antagonistic effect at very low concentrations. However, at higher concentrations the inhibitors exhibited a synergistic effect in inhibiting viral replication. Preliminary results on investigation of the mechanism of inhibition indicate that YZ-LY-0 does not block the entry of the virus in the host cell, but instead inhibits an early stage of EV71 replication. Our studies provide a potential clinical therapeutic option against EV71 infections and suggest that a combined application of YZ-LY-0 with other inhibitors could be more effective in the treatment of HFMD. 相似文献
12.
噬菌体展示技术筛选大鼠佐剂性关节炎中PGE2受体的拮抗剂 总被引：1，自引：0，他引：1
目的：通过筛选PGE2受体拮抗剂,来探讨其在类风湿性关节炎（rheumatoid arthritis, RA）中的作用,为RA的治疗开辟新的途径。方法：应用噬菌体展示技术,以PGE2为靶点,对噬菌体环七肽库进行\"吸附-洗脱-扩增\"筛选过程,5轮筛选后,随机挑取噬菌体克隆进行亲和力鉴定,并选取亲和力高的克隆进行测序并对序列进行分析。合成环七肽后,建立佐剂性关节炎（AA）动物模型,通过分析足爪肿胀度,以及采用ELISA方法检测关节浸液中细胞因子的含量,对小肽的抗炎作用进行探讨。结果：噬菌体经过富集后,随机挑选的23个克隆中有21个阳性克隆,而在测序的8个克隆中4个具有相同的序列,其余也具有保守氨基酸。合成的环七肽能降低AA关节的肿胀度并减少关节浸液中前炎症细胞因子的含量。结论:噬菌体筛选PGE2受体拮抗剂的方法可行,并且得到的环七肽具有一定的抗炎作用。 相似文献
13.
肠道病毒71型的RT-PCR诊断及基因特征 总被引：62，自引：1，他引：62
2002～2003年从上海市和重庆市手足口病患儿的疱液标本中分离到10株病毒,其中上海9株,重庆1株.利用两对分别针对EV71和Cox.A16病毒VP1区的特异性引物,用RT-PCR方法对病毒进行初步鉴别.根据PCR所用引物及PCR扩增出的产物片段大小不同,可初步判定出EV71和Cox.A16病毒的血清型别.RT-PCR结果提示,上海分离到的9株病毒中,有2株为EV71,其余7株病毒为Cox.A16;重庆分离到的1株病毒为EV71.10株病毒的RT-PCR产物经序列测定和分析证实,PCR定型结果正确,说明PCR法具有很高的特异性,可作为EV71初步鉴定的首选方法.对所分离的3株EV71病毒进行VP1区编码基因全序列的测定和遗传学分析,通过同源性比较和构建系统发生树发现,此3株EV71病毒和中国大陆已发表的7株EV71病毒(SHZH03、SHZH98、SH-F1、SH-F2、SH-H25、SH-H26和CHN-87)全部属于C基因型,与该型代表株比较,同源性为89.3%～94.6%;与A、B基因型代表株比较,同源性为81.3%～84.0%,差异较大.在C基因型中,此3株EV71病毒和中国大陆先前分离的6株病毒(SHZH03、SHZH98、SH-F1、SH-F2、SH-H25、SH-H26)的同源性较高,在94.5%～100%范围内.在系统发生树上,这9株病毒形成一个较独立的分支.与CHN-87株的同源性在92.1%～93.6%之间.与已知的C1、C2、C3亚型代表株比较,同源性在89.3%～92.9%,差异≥7%,因此认为可将这9株病毒划分为C4亚型.上海、重庆和深圳的EV71病毒有较高的同源性,提示该病毒EV71-CA亚型在中国大陆1998～2003年间有较广泛的传播.建立中国流行的EV71病毒毒株库和基因库,对诊断、预防和控制EV71在中国的爆发有重要意义,对加强EV71的实验室诊断、病毒学监测和病毒基因型和亚型的标准命名和分子流行病学研究有重要帮助. 相似文献
14.
Junrui Ren Lei Yu Qiuhan Zhang Pengyu Ren Yumeng Cai Xueyun Wang Ke Lan Shuwen Wu 《中国病毒学》2024,39(4):632-644
Hand, foot and mouth disease (HFMD), mainly caused by enterovirus 71 (EV71), has frequently occurred in the Asia-Pacific region, posing a significant threat to the health of infants and young children. Therefore, research on the infection mechanism and pathogenicity of enteroviruses is increasingly becoming important. The 3D polymerase, as the most critical RNA-dependent RNA polymerase (RdRp) for EV71 replication, is widely targeted to inhibit EV71 infection. In this study, we identified a novel host protein, AIMP2, capable of binding to 3D polymerase and inhibiting EV71 infection. Subsequent investigations revealed that AIMP2 recruits the E3 ligase SMURF2, which mediates the polyubiquitination and degradation of 3D polymerase. Furthermore, the antiviral effect of AIMP2 extended to the CVA16 and CVB1 serotypes. Our research has uncovered the dynamic regulatory function of AIMP2 during EV71 infection, revealing a novel antiviral mechanism and providing new insights for the development of antienteroviral therapeutic strategies. 相似文献
15.
Minghao Dang Xiangxi Wang Quan Wang Yaxin Wang Jianping Lin Yuna Sun Xuemei Li Liguo Zhang Zhiyong Lou Junzhi Wang Zihe Rao 《蛋白质与细胞》2014,5(9):692-703
Unlike the well-established picture for the entry of enveloped viruses, the mechanism of cellular entry of non-enveloped eukaryotic viruses remains largely mysterious. Picornaviruses are representative models for such viruses, and initiate this entry process by their functional receptors. Here we present the structural and functional studies of SCARB2, a functional receptor of the important human enterovirus 71 (EV71). SCARB2 is responsible for attachment as well as uncoating of EV71. Differences in the structures of SCARB2 under neutral and acidic conditions reveal that SCARB2 undergoes a pivotal pH-dependent conformational change which opens a lipid-transfer tunnel to mediate the expulsion of a hydrophobic pocket factor from the virion, a pre-requisite for uncoating. We have also identified the key residues essential for attachment to SCARB2, identifying the canyon region of EV71 as mediating the receptor interaction. Together these results provide a clear understanding of cellular attachment and initiation of uncoating for enteroviruses 相似文献
16.
Prospective isolation of late development multipotent precursors whose migration is promoted by EGFR
A simple procedure to isolate neural stem cells would greatly facilitate direct studies of their properties. Here, we exploited the increase in EGF receptor (EGFR) levels, that occurs in late development stem cells or in younger precursors upon exposure to FGF-2, to isolate cells expressing high levels of EGFR (EGFR(high)) from the developing and the adult brain. Independently of age and region of isolation, EGFR(high) cells were highly enriched in multipotent precursors and displayed similar antigenic characteristics, with the exception of GFAP and Lex/SSEA-1 that were mainly expressed in adult EGFR(high) cells. EGFR levels did not correlate with neurogenic potential, indicating that the increase in EGFR expression does not directly affect differentiation. Instead, in the brain, many EGFR(high) precursors showed tangential orientation and, whether isolated from the cortex or striatum, EGFR(high) precursors displayed characteristics of cells originating from the ventral GZ such as expression Dlx and Mash-1 and the ability to generate GABAergic neurons and oligodendrocytes. Moreover, migration of EGFR(high) cells on telencephalic slices required EGFR activity. Thus, the developmentally regulated increase in EGFR levels may affect tangential migration of multipotent precursors. In addition, it can be used as a marker to effectively isolate telencephalic multipotent precursors from embryonic and adult tissue. 相似文献
17.
Cao Jiaming Qu Meng Liu Hongtao Wan Xuan Li Fang Hou Ali Zhou Yan Sun Bo Cai Linjun Su Weiheng Jiang Chunlai 《中国病毒学》2020,35(5):599-613
Virologica Sinica - The Enterovirus 71 (EV71) VP4 is co-translationally linked to myristic acid at its amino-terminal glycine residue. However, the role of this myristoylation in the EV71 life... 相似文献
18.
肠道病毒71型(EV71)的非结构蛋白2C(P2C)在病毒复制周期中起着重要的作用,制备P2C的特异性抗体,对研究P2C的生物学功能以及EV71与宿主相互作用的具体机制有非常重要的意义。实验将2C基因克隆到原核表达载体p ET-28a(+)上,在大肠埃希菌BL21(DE3)中表达出重组蛋白r P2C,进一步优化原核表达条件,在温度为30℃,诱导剂IPTG浓度为1 mmol/L时,蛋白表达量最高,且主要以包涵体形式存在。直接将获得的r P2C通过SDS-PAGE分离后免疫新西兰兔,制备EV71病毒P2C的兔多克隆抗体。通过Western blot检测,该抗体在110 000稀释比例下仍能很好地识别原核表达的r P2C。同时该抗体也能很好地检测到EV71感染RD细胞中的P2C。因此,实验制备出的抗P2C抗体特异性强、效价高,为后续P2C功能的研究以及EV71病毒检测提供了良好的材料。 相似文献
19.
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 31.2 μg/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）. 相似文献
20.