关键词： 荧光定量逆转录-聚合酶链反应(rRT-PCR)   脊髓灰质炎病毒   型内鉴定  

摘要： 目的应用实时荧光定量逆转录-聚合酶链反应(rRT-PCR)对脊髓灰质炎病毒(PV)进行型内鉴定,为进行常规rRT-PCR型内鉴定方法奠定基础。方法采用世界卫生组织(WHO)推荐的rRT-PCR方法,对WHO发放的PV株和实验室分离的PV株进行型内鉴定(ITD)和疫苗衍生PV株(VDPV)筛选。结果 ITD rRT-PCR的实验结果与毒株的VP1编码区序列测定结果完全相符,VDPV rRT-PCR的结果与VP1编码区序列测定结果大部分相符,但有2株Ⅱ型脊髓灰质炎疫苗类似株(SL)PV2-SL被错判为非疫苗类似株(NSL),假阳性率为3.03%;1株Ⅲ型SL被错判为NSL,假阳性率为1.92%。结论在新疆脊髓灰质炎实验室rRT-PCR可以应用于脊髓灰质炎病毒的常规监测及型内鉴定。

关键词： 急性弛缓性麻痹   疫苗重组脊髓灰质炎病毒   VP1编码区  

摘要： 目的鉴定吉林省从急性弛缓性麻痹病例粪便标本中分离的1株VP1编码区Ⅲ/Ⅱ型疫苗重组脊髓灰质炎(脊灰)病毒[Vaccine-recombinant Poliovirus(PV),VRPV]。方法粪便标本采自1例2岁吉兰-巴雷综合征病例,使用转人PV受体的小鼠肺细胞系(Mouse Cell Line Expressing the Gene for the Human Cellular Receptor for PV,L20B)细胞和人横纹肌肉瘤(Human Rhabdomyosarcoma,RD)细胞进行病毒分离,阳性标本进行中和试验(Neutralization Test,NT)鉴定血清型,并通过逆转录-聚合酶链反应进行VP1编码区扩增和核苷酸序列测定,利用Bioedit软件对该序列结果与赛宾(Sabin)疫苗株PV进行核苷酸和氨基酸序列比对,分析重组位点的位置以及核苷酸和氨基酸的变异情况。结果该标本接种到RD和L20B细胞后,均发生了肠道病毒特征性病变,经血清学定型,结果为Ⅱ+Ⅲ型PV。VP1编码区核苷酸序列分析表明,其中的Ⅱ型PV与Sabin 2株PV比较,发生了1个核苷酸变异;Ⅲ型PV为VP1编码区Ⅲ型与Ⅱ型VRPV,与相对应的Sabin株PV相比,无核苷酸点变异,在VP1编码区重组的Ⅱ型PV序列为106个核苷酸。血清NT证明,该VRPV仍能被Ⅲ型完全中和,而不能被Ⅱ型中和。结论虽然Ⅲ型PV株中插入了Ⅱ型抗原位点NAg3a,但Ⅲ型PV株总体的型特异性抗原特征未发生改变。PV自然重组很少发生在衣壳蛋白编码区,发现的这株VRPV中和特性与Sabin株PV相比未发生变化。

关键词： POLIOVIRUS   RESEARCH   CELL membranes   CAPSIDS (Viruses)   VIRUSES   LIGANDS  

摘要： Poliovirus infection is initiated by attachment to a receptor on the cell surface called Pvr or CD155. At physiological temperatures, the receptor catalyzes an irreversible expansion of the virus to form an expanded form of the capsid called the 135S particle. This expansion results in the externalization of the myristoylated capsid protein VP4 and the N-terminal extension of the capsid protein VP1, both of which become inserted into the cell membrane. Structures of the expanded forms of poliovirus and of several related viruses have recently been reported. However, until now, it has been unclear how receptor binding triggers viral expansion at physiological temperature. Here, we report poliovirus in complex with an enzymatically partially deglycosylated form of the 3-domain ectodomain of Pvr at a 4-angstrom resolution, as determined by cryo-electron microscopy. The interaction of the receptor with the virus in this structure is reminiscent of the interactions of Pvr with its natural ligands. At a low temperature, the receptor induces very few changes in the structure of the virus, with the largest changes occurring within the footprint of the receptor, and in a loop of the internal protein VP4. Changes in the vicinity of the receptor include the displacement of a natural lipid ligand (called "pocket factor"), demonstrating that the loss of this ligand, alone, is not sufficient to induce particle expansion. Finally, analogies with naturally occurring ligand binding in the nectin family suggest which specific structural rearrangements in the virus-receptor complex could help to trigger the irreversible expansion of the capsid. IMPORTANCE The cell-surface receptor (Pvr) catalyzes a large structural change in the virus that exposes membrane-binding protein chains. We fitted known atomic models of the virus and Pvr into three-dimensional experimental maps of the receptor-virus complex. The molecular interactions we see between poliovirus and its receptor are reminiscent

关键词： Polio eradication   Antiviral therapy   Drug-resistance   Chronic virus excretors   Emergency prophylaxis  

摘要： Background: Development of anti-poliovirus therapies to complement vaccination is an urgent priority. A number of antiviral drugs are in development. Recently we have developed human monoclonal antibodies that could be used for treatment of chronically infected individuals and emergency response to potential reappearance of polioviruses after eradication. Objective: The aim of this study was to characterize neutralizing activity of anti-poliovirus monoclonal antibody A12 against wild type, vaccine-derived, and drug-resistant poliovirus strains, evaluate in vivo pre- and post-exposure protective properties of the antibody against polioviruses of serotypes 1 and 2, and to determine whether it interferes with response to immunization with poliovirus vaccine. Study design: Immunogenicity studies were performed in CD1 mice. Poliovirus neutralizing titers were determined in poliovirus microneutralization assay. Poliovirus immunization-challenge experiments were performed in poliovirus-susceptible TgPVR21 mice. Results: We show that monoclonal antibody A12 effectively neutralizes in vitro a broad range of type 1 and type 2 wild and vaccine-derived polioviruses, provides effective pre- and post-exposure protection of TgPVR21 mice from challenge with a lethal dose of poliovirus. Treatment of animals with the antibody concurrent with IPV immunization does not prevent immune response to the vaccine. Conclusions: Anti-poliovirus antibody A12 effectively neutralizes a range of wild and VDPV strains and protectstransgenic mice susceptible to poliovirus against lethal challenge upon pre- and post-exposure administration. This suggests that the antibodies could be used in combination with drugs and/or vaccine to improve their efficacy and prevent emergence of resistant variants, and provides a justification for initiating their clinical evaluation. Published by Elsevier B.V.

关键词： Oral polio vaccine   Immunodeficiency   iVDPV   Polio eradication   Poliomyelitis  

摘要： Background: Vaccine-derived polioviruses (VDPVs), strains of poliovirus mutated from the oral polio vaccine, pose a challenge to global polio eradication. Immunodeficiency-related vaccine-derived polioviruses (iVDPVs) are a type of VDPV which may serve as sources of poliovirus reintroduction after the eradication of wild-type poliovirus. This review is a comprehensive update of confirmed iVDPV cases published in the scientific literature from 1962 to 2012, and describes clinically relevant trends in reported iVDPV cases worldwide. Methods: We conducted a systematic review of published iVDPV case reports from January 1960 to November 2012 from four databases. We included cases in which the patient had a primary immunodeficiency, and the vaccine virus isolated from the patient either met the sequencing definition of VDPV (>1% divergence for serotypes 1 and 3 and >0.6% for serotype 2) and/or was previously reported as an iVDPV by the World Health Organization. Results: We identified 68 iVDPV cases in 49 manuscripts reported from 25 countries and the Palestinian territories. 62% of case patients were male, 78% presented clinically with acute flaccid paralysis, and 65% were iVDPV2. 57% of cases occurred in patients with predominantly antibody immunodeficiencies, and the overall all-cause mortality rate was greater than 60%. The median age at case detection was 1.4 years [IQR: 0.8, 4.5] and the median duration of shedding was 1.3 years [IQR: 0.7, 2.2]. We identified a poliovirus genome VP1 region mutation rate of 0.72% per year and a higher median percent divergence for iVDPV1 cases. More cases were reported from high income countries, which also had a larger age variation and different distribution of immunodeficiencies compared to upper and lower middle-income countries. Conclusion: Our study describes the incidence and characteristics of global iVDPV cases reported in the literature in the past five decades. It also highlights the regional and economic disparities of r

关键词： 脑膜炎疫苗   脊髓灰质炎   免疫效果监测   乙型脑炎   流行性   麻疹   疾病预防控制中心   预防接种工作  

摘要： 为了贯彻落实卫生部《预防接种工作规范》，了解儿童接种疫苗后的免疫状况，按照“知情、同意、自愿、自费”的原则，杏花岭区疾病预防控制中心于2012年10月至2013年5月对辖区内三个社区的1～15周岁的儿童开展脊髓灰质炎（简称：脊灰）、麻疹、乙型脑炎、流行性脊髓脑膜炎（简称：流脑）4种疫苗的抗体检测工作，对无抗体的儿童可以免费补种疫苗。此项工作的开展可以了解辖区居住儿童脊灰、麻疹、乙脑、流脑的免疫状况，评价免疫接种的效果，还可以为制定免疫预防策略和工作方案提供科学依据。

关键词： 灭活轮状病毒疫苗   灭活脊髓灰质炎疫苗   联合免疫  

摘要： 目的评价灭活轮状病毒疫苗(inactivated rotavirus vaccine,IRV)与灭活脊髓灰质炎病毒疫苗(inactivated poliovirus vaccine,IPV)免疫大鼠后,两种疫苗间免疫效果的相互作用。方法将Wistar大鼠随机分成联合免疫组、间隔免疫组和单疫苗免疫组:联合免疫组接种IPV后4周,经双侧腿同时免疫IPV和IRV,共2次,间隔4周;单疫苗免疫组2组,分别免疫3针IPV和2针IRV,每针均间隔4周;间隔免疫组免疫1针IPV后4周,开始进行IPV和IRV间隔免疫(每针间隔2周,共6周)。分别于每次免疫后4周经尾静脉采血,分离血清,采用微量中和试验结合免疫荧光抑制方法检测血清抗RV中和抗体水平,ELISA法检测血清抗RV特异性Ig G抗体水平,微量中和试验法检测血清抗脊髓灰质炎病毒中和抗体水平。结果大鼠经2针IRV免疫后,血清抗RV中和抗体和特异性Ig G抗体几何平均滴度(geometric mean titer,GMT)均明显上升,血清抗体阳转率均达100%;经3针IPV免疫后,Ⅰ、Ⅱ、Ⅲ型脊髓灰质炎病毒中和抗体GMT均明显上升,抗体阳转率均达100%;联合免疫组、间隔免疫组和单疫苗免疫组间血清抗RV中和抗体水平、特异性Ig G抗体水平及抗脊髓灰质炎病毒中和抗体水平差异无统计学意义(P>0.05)。结论 IRV和IPV免疫大鼠后均获得到良好的免疫效果,两种疫苗联合使用时,免疫效果无相互干扰作用。

关键词： 脊髓灰质炎病毒   流感嗜血杆菌   急性人   肢体麻痹   脊灰   保护屏障   出生后   免疫程序   营养供给   百白破  

摘要： 宝宝出生后,离开母体营养供给这一天然保护屏障后,先天性的抵抗力也随之下降,随着接触外界环境中细菌、病毒等机会的增多,患病的风险也大大增加。宝宝太小,很多药物使用受限,使治疗难上加难。这可怎么办？

关键词： 脊髓灰质炎   强化免疫   效果分析  

摘要： 目的分析湖南省益阳市南县2013—2014年脊髓灰质炎疫苗(OPV)强化免疫效果,为今后OPV强化免疫活动提供参考。方法根据湖南省卫生厅湘卫疾控处《关于印发(湖南省2013/2014年脊髓灰质炎疫苗强化免疫技术方案)的通知》和南县卫生局《关于印发(南县2013/2014年脊髓灰质炎疫苗强化免疫技术方案)的通知》等文件要求开展工作并对强化免疫资料进行分析。结果本轮强化免疫对象为2011年1月1日—2013年9月30日出生的儿童.全县常住应种儿童数为18217人,流动应种儿童数为693人。2轮强化免疫常住儿童实际投服分别为17686人和17575人,接种率分别为97.08%和96.47%;2轮强化免疫流动儿童实际投服分别为686人和682人,接种率分别为98.98%和98.41%,2轮强化免疫常住儿童和流动儿童接种率,差异无统计学意义(P>0.05)。强化免疫前"零"剂次儿童共886人,占总服苗儿童4.7%。结论该次脊髓灰质炎疫苗强化免疫活动组织有序扎实,经费、宣传、培训等均比较到位,保障了强化免疫活动的进行,提高了全县儿童接种率,对于阻断脊髓灰质炎病毒传播具有重要意义。

关键词： 脊髓灰质炎病毒   蔗糖垫层   纯化  

摘要： 目的建立可大规模纯化脊髓灰质炎病毒(poliovirus,PV)的蔗糖垫层离心法。方法病毒大量增殖后,收集病毒液,经PEG浓缩、三氟三氯乙烷抽提后,采用蔗糖垫层或Cs Cl密度梯度离心法纯化PV(Ⅰ、Ⅱ、Ⅲ型),电镜下观察病毒形态,进行核酸及感染性滴度的检测。将纯化的Ⅰ、Ⅱ、Ⅲ型PV免疫豚鼠,心脏采血,分离血清,微量中和试验法检测血清中和抗体滴度。结果蔗糖垫层离心法纯化的各型PV,病毒颗粒形态典型,背景清晰,除完整的光滑型病毒颗粒外,还可见大量空心病毒颗粒样品,纯化效果较好;Cs Cl密度梯度离心法纯化的PV样品,病毒形态也较典型,但完整的病毒颗粒较多。两种纯化方法获得的病毒基因组核酸特征显著,背景清晰,无明显差异。蔗糖垫层离心法纯化的各型PV的感染性滴度及免疫后豚鼠血清中和抗体滴度均高于Cs Cl密度梯度离心法。结论蔗糖垫层离心法纯化的PV纯度高,免疫原性好,可用于大规模纯化PV或其他病毒。