关键词： 刺突蛋白   受体结合功能域   蝙蝠SARS样冠状病毒   杆状病毒  

摘要： 目的:在昆虫细胞表达系统中表达蝙蝠SARS样冠状病毒Spike蛋白的受体结合域,并探讨其表达动力学和纯化条件。方法:以PCR扩增蝙蝠SARS样冠状病毒Spike基因的受体结合域片段,产物连接到pMD-T载体,再亚克隆至供体质粒pFAST-HTB,经序列测定确认基因正确克隆,进一步将其转座入Bacmid中,在昆虫细胞Sf9中进行表达,采用SDS-PAGE和Western blotting对表达产物进行分析,并通过镍离子螯合树脂纯化重组蛋白。结果:在昆虫细胞表达系统中表达出蝙蝠SARS样冠状病毒Spike蛋白的受体结合域片段,当感染复数(multiplicity of infectiin,MOI)为2时,重组病毒感染细胞56 h后,重组蛋白的表达量达到峰值。结论:蝙蝠SARS样冠状病毒Spike蛋白的受体结合域片段在昆虫细胞表达系统中得到了有效表达,并可通过镍离子螯合树脂纯化重组蛋白。

关键词： Animals   Chiroptera/virology   Hendra Virus/classification   Hendra Virus/genetics  

摘要： Hendra virus (HeV) causes a zoonotic disease with high mortality that is transmitted to humans from bats of the genus Pteropus (flying foxes) via an intermediary equine host. Factors promoting spillover from bats to horses are uncertain at this time, but plausibly encompass host and/or agent and/or environmental factors. There is a lack of HeV sequence information derived from the natural bat host, as previously sequences have only been obtained from horses or humans following spillover events. In order to obtain an insight into possible variants of HeV circulating in flying foxes, collection of urine was undertaken in multiple flying fox roosts in Queensland, Australia. HeV was found to be geographically widespread in flying foxes with a number of HeV variants circulating at the one time at multiple locations, while at times the same variant was found circulating at disparate locations. Sequence diversity within variants allowed differentiation on the basis of nucleotide changes, and hypervariable regions in the genome were identified that could be used to differentiate circulating variants. Further, during the study, HeV was isolated from the urine of flying foxes on four occasions from three different locations. The data indicates that spillover events do not correlate with particular HeV isolates, suggesting that host and/or environmental factors are the primary determinants of bat-horse spillover. Thus future spillover events are likely to occur, and there is an on-going need for effective risk management strategies for both human and animal health.

关键词： chiroptera   pathogen persistence   torpor  

摘要： Rabies is an acute viral infection that is typically fatal. Most rabies modeling has focused on disease dynamics and control within terrestrial mammals (e. g., raccoons and foxes). As such, rabies in bats has been largely neglected until recently. Because bats have been implicated as natural reservoirs for several emerging zoonotic viruses, including SARS-like corona viruses, henipaviruses, and lyssaviruses, understanding how pathogens are maintained within a population becomes vital. Unfortunately, little is known about maintenance mechanisms for any pathogen in bat populations. We present a mathematical model parameterized with unique data from an extensive study of rabies in a Colorado population of big brown bats (Eptesicus fuscus) to elucidate general maintenance mechanisms. We propose that life history patterns of many species of temperate-zone bats, coupled with sufficiently long incubation periods, allows for rabies virus maintenance. Seasonal variability in bat mortality rates, specifically low mortality during hibernation, allows long-term bat population viability. Within viable bat populations, sufficiently long incubation periods allow enough infected individuals to enter hibernation and survive until the following year, and hence avoid an epizootic fadeout of rabies virus. We hypothesize that the slowing effects of hibernation on metabolic and viral activity maintains infected individuals and their pathogens until susceptibles from the annual birth pulse become infected and continue the cycle. This research provides a context to explore similar host ecology and viral dynamics that may explain seasonal patterns and maintenance of other bat-borne diseases.

关键词： 蝙蝠蛾被孢菌丝体   多糖   淋巴细胞   巨噬细胞  

摘要： 目的探讨蝙蝠蛾被孢菌丝体多糖免疫调节作用的机理。方法将不同剂量的蝙蝠蛾被孢菌丝体多糖加入体外培养的小鼠淋巴细胞中,观察其对淋巴细胞增殖的影响。另外取CPSM培养的巨噬细胞RAW264.7,观察CPSM对巨噬细胞增殖、NO释放及吞噬中性红功能的影响。结果 CPSM具有促进体外培养的小鼠脾脏淋巴细胞增殖及促进巨噬细胞RAW264.7增殖、释放NO及吞噬功能。结论本研究为冬虫夏草增强免疫机能作用提供了依据。

关键词： PTEROPODIDAE   INTERFERONS   IMMUNITY   ZOONOSES   DOUBLE-stranded RNA  

摘要： Bats are known to harbor a number of emerging and re-emerging zoonotic viruses, many of which are highly pathogenic in other mammals but result in no clinical symptoms in bats. The ability of bats to coexist with viruses may be the result of rapid control of viral replication early in the immune response. IFNs provide the first line of defense against viral infection in vertebrates. Type III IFNs (IFN-lambda s) are a recently identified IFN family that share similar antiviral activities with type I IFNs. To our knowledge, we demonstrate the first functional analysis of type III IFNs from any species of bat, with the investigation of two IFN-lambda genes from the pteropid bat, Pteropus alecto. Our results demonstrate that bat type III IFN has similar antiviral activity to type I and III IFNs from other mammals. In addition, the two bat type III IFNs are differentially induced relative to each other and to type I IFNs after treatment or transfection with synthetic dsRNA. Infection with the bat paramyxovirus, Tioman virus, resulted in no upregulation of type I IFN production in bat splenocytes but was capable of inducing a type III IFN response in three of the four bats tested. To our knowledge, this is the first report to describe the simultaneous suppression of type I IFN and induction of type III IFN after virus infection. These results may have important implications for the role of type III IFNs in the ability of bats to coexist with viruses. The Journal of Immunology, 2011, 186: 3138-3147.

关键词： BATS   CORONAVIRUSES   NIDOVIRUSES   RNA viruses   ADENOVIRUSES   PATHOGENIC microorganisms  

摘要： Bats host noteworthy viral pathogens, including coronaviruses, astroviruses, and adenoviruses. Knowledge on the ecology of reservoir-borne viruses is critical for preventive approaches against zoonotic epidemics. We studied a maternity colony of Myotis myotis bats in the attic of a private house in a suburban neighborhood in Rhineland-Palatinate, Germany, during 2008, 2009, and 2010. One coronavirus, 6 astroviruses, and 1 novel adenovirus were identified and monitored quantitatively. Strong and specific amplification of RNA viruses, but not of DNA viruses, occurred during colony formation and after parturition. The breeding success of the colony was significantly better in 2010 than in 2008, in spite of stronger amplification of coronaviruses and astroviruses in 2010, suggesting that these viruses had little pathogenic influence on bats. However, the general correlation of virus and bat population dynamics suggests that bats control infections similar to other mammals and that they may well experience epidemics of viruses under certain circumstances.

关键词： 蝙蝠蛾被孢霉菌丝体   多糖   抑瘤   免疫调节  

摘要： 目的:观察蝙蝠蛾被孢霉菌丝体多糖(CPSM)对荷瘤小鼠抑瘤及免疫功能的影响。方法:应用水提醇沉法从蝙蝠蛾被孢霉虫草菌丝体(CSM)中获得CPSM,将荷瘤小鼠分组并灌胃不同剂量CPSM(11、33、100 mg/(kg.d))10d,观察药物抗肿瘤及免疫增强的作用。结果:CPSM33 mg/(kg.d)CPSM对H22荷瘤小鼠有明显的抑瘤作用,抑瘤率为43.49%,且能促进小鼠的胸腺指数和脾指数。33、100 mg/(kg.d)剂量能显著提高小鼠的血清溶血素水平(P<0.01),增强小鼠的碳粒廓清能力(P<0.05)。结论:蝙蝠蛾被孢霉菌丝体多糖能明显抑制H22肝癌,并调节机体体液免疫功能,促进巨噬细胞的吞噬能力。

关键词： Bats   coronavirus   Rhinolophus spp   SARS  

摘要： The association between coronaviruses and bats is a worldwide phenomenon and bats belonging to genus Rhinolophus are the reservoir host for several coronaviruses, including a large number of viruses closely related genetically to severe acute respiratory syndrome-coronavirus (SARS-CoV). We carried out a survey in colonies of Italian bats (Rhinolophus ferrumequinum) for the presence of coronaviruses. Two of 52 R. ferrumequinum captured from different Italian areas tested positive by reverse transcription-PCR for a fragment of RNA-dependent RNA polymerase (RdRp) gene of viruses related to Coronavirus. Phylogenetic analysis revealed close correlations between one of the positive samples and SARS-related CoV belonging to the genus Betacoronavirus.

关键词： 色觉   行为学   免疫组织化学   视觉诱发电位   蝙蝠  

摘要： 蝙蝠(翼手目,Chiroptera)作为哺乳动物的第二大类群,是唯一真正具有飞行能力的兽类,行夜行性生活,这种进化上的优势使它们利用了兽类中一个全新的生态位。蝙蝠具有极其丰富的物种多样性,在生态系统中扮演着不可或缺的角色,因此对蝙蝠的保护和研究具有很重要的意义。因其具有独特的回声定位能力,目前对蝙蝠的研究主要集中在听觉领域,而对其视觉尤其是色觉的研究很少。 本研究首次运用行为学、免疫组织化学和神经电生理学三种技术手段对四类蝙蝠的色觉进行了研究。结果表明,调频小蝙蝠和树栖的大蝙蝠具有紫外视觉,而恒频小蝙蝠和洞栖的大蝙蝠不具有紫外视觉,进一步验证了前期分子学研究的结论(Zhao et al.,2009)。大蝙蝠原本生活在树上,进化过程中有小部分栖息地变为基本无光的洞穴,其结果导致了这部分旧大陆果蝠视觉发生退化。对恒频蝙蝠而言,视觉退化的根本原因在于它具有一种更发达的回声定位能力。发达的听觉使恒频蝙蝠不再需要发达的视觉,进而引起视觉退化。这也与前人提出的感觉代偿理论相符合(Speakman,2001). 我们还发现,调频小蝙蝠、恒频小蝙蝠和洞栖大蝙蝠的视觉诱发电位都在中/长波段550nm附近出现一个反应峰值,树栖大蝙蝠的视觉诱发电位虽没有在此波段出现明显的反应峰值,但中/长波段反应的最大值也出现在550nm附近。这与分子学证据,即中/长波长视蛋白(M/LWS)基因在哺乳动物中高度保守,大部分蝙蝠M/LWS的最大光吸收值在553nm相符(Zhao et al.,2009)。

关键词： 蝙蝠   诺如病毒   星状病毒   进化树分析   检出率  

摘要： 研究背景和目的 研究表明,蝙蝠是多种人兽共患疾病病毒的自然宿主,并可以跨越物种间屏障,将病毒传播给人类和其他动物。目前研究人员已经从蝙蝠身上发现或分离很多种病毒,约有18个病毒科包含70多种病毒。已知能从蝙蝠传播给人类的病毒主要有狂犬病毒、尼巴病毒、亨德拉病毒,还有类SARS冠状病毒,这些病毒都可以引起人类致命性的疾病。其他病毒,如甲病毒属、黄病毒属和布尼亚病毒属病毒可通过节肢动物传播给蝙蝠,但还不确定蝙蝠是不是这类病毒所致疾病的播散宿主。可见,还需要大量研究,以明确蝙蝠在病毒性自然疫源性疾病中所扮演的角色。 我国约有120种蝙蝠,但国内对蝙蝠的研究工作起步较晚,对其生态学、行为学研究尚不够深入,尤其是对我国蝙蝠携带哪些种类病毒,以及病毒与蝙蝠生态学的关系,对人类健康的影响的研究还较少。迄今为止,我国科研工作者对蝙蝠所携带病毒的研究有以下发现：从蝙蝠体内分离到罗斯河病毒、乙型脑炎病毒、基孔肯雅病毒、森林脑炎病毒、SARS类冠状病毒、狂犬病病毒、星状病毒、尼巴病毒等。这些发现表明我国蝙蝠可携带某些我国常见传染病的病毒。 病毒性胃肠炎（viral gastroenteritis）又称病毒性腹泻,是一组由多种病毒引起的急性肠道传染病。临床特点为起病急、恶心、呕吐、腹痛、腹泻,排水样便或稀便,也可有发热及全身不适等症状,病程短,病死率低。病毒性腹泻在儿童中更是一种常见病和多发病,是导致儿童死亡的重要原因。引起儿童腹泻的病毒主要有轮状病毒（rotavirus）、肠道腺病毒（adenovirus）、星状病毒（astrovirus, Astv）、诺如病毒（norovirus, NoV）等。 患者与无症状带毒者是病毒性胃肠炎的主要传染源。粪-口途径传播是病毒性胃肠炎最重要的传播途径,少部分可以通过空气传播,其可通过被污染的食物或水引起人群胃肠炎暴发或散发。回顾上世纪90年代的亨德拉病毒和尼帕病毒的暴发事件,也是源于食源性感染,是由于蝙蝠病毒污染了水域、水果,再依次传播给马、猪、人,最后导致疾病暴发。 星状病毒（Astrovirus, Astv）于1975年在胃肠炎患儿粪便标本中首次发现,由于电镜下病毒颗粒呈星形,因此被命名为星状病毒。此后世界各地均已有星状病毒感染的报道,它既可散发也可以引起暴发流行,亦可引起医源性感染。住院腹泻患儿中星状病毒检出率为2.5%-9.0%,目前认为星状病毒是婴幼儿病毒性胃肠炎的第二位病因,仅次于轮状病毒。 星状病毒既可感染人,也可感染牛、羊、猪、狗、鹿、火鸡、鸭、鼠等多种动物,导致不同程度的胃肠炎。人群感染的星状病毒,传统上可分为8个血清型。最近,研究者又在腹泻病人中发现两种的新星状病毒,astrovirus MLB和astrovirus VA。研究还发现,Astv MLB 1与新近发现的鼠星状病毒很相近;Astv VA1在进化树上与感染羊和貂的星状病毒最为接近。这提示新发现的人星状病毒可能和动物的星状病毒存在一定的关系。 近年来,香港大学研究小组分别从香港和中国大陆的蝙蝠体内检出星状病毒,检出率高达46%和44.8%；基因分析显示蝙蝠星状病毒具有高度基因多态性,部分病毒可能与感染人的星状病毒有系统进化的关系。然而关于蝙蝠星状病毒的生态学资料还很稀少,有必要进一步扩充不同地区和不同种类的蝙蝠样本进行研究。 诺如病毒（Norovirus, NoV）是一组杯状病毒属病毒,其原型株诺瓦克病毒于1972年在美国诺瓦克市被分离发现。由于该组病毒极易变异,此后在其他地区又相继发现并命名了多种类似病毒,统称为诺如病毒。NoV是一种高致病的、传染性极强的肠胃病毒,能导致急性胃肠炎,一旦有人感染,通常会发展为群体性的大规模传染。遗憾的是,由于病毒的高度变异性及其缺少合适的动物研究模型,现今还未研发出理想的NoV疫苗,患者容易发生反复感染。 自然界中携带NoV的物种很多,包括有人、猪、牛、鼠、海狮等,可导致它们发生不同程度的症状。根据基因特征,NoV被分为五个遗传群（Gene Group, GG）:GGⅠ、GGⅡ、GGⅢ、GGⅣ和GGV。五个遗传群中,GGⅠ、GGⅡ和GGIV主要感染人类,GGⅢ感染牛,GGV则在鼠类动物内检出。 虽然研究已表明NoV在多种动物体内广泛存在,但是关于动物NoV感染的流行病学还不太清楚。动物NoV在动物体内感染率差别较大,研究发现北美的实验鼠鼠类NoV的感染率高达22.1%,英国检测发现牛的腹泻病例中有11%比例为NoV感染所致,而猪NoV检出率比较低,在日本猪GGⅡNoV的检测率仅为0.35%,在荷兰检测率为2.0%。 尽管现今没有证据表明动物NoV可以感染人类,但是分子生物学分析表明动物NoV和人类NoV的毒株相互之间有密切的关系,尤