检测流行性出血热病毒滴度和中和抗体效价的半微量空斑法

建立了检测流行性出血热病毒滴度和中和抗体效价的半微量空斑法。小牛血清与胎牛血清的培养效果无差异。7株不同来源的出血热病毒均能在E6细胞上形成空斑。接种的病毒浓度与形成的空斑数呈直线关系。用空斑法测得的病毒滴度稍低于荧光TCIE50滴定法。空斑减少中和试验的敏感性较荧光中和试验高30倍左右。同时还初步表明了本方法可用于流行性出血热病毒的抗原性分析。     

中国新疆维吾尔自治区不明原因发热人群中Tahyna病毒感染状况调查

本研究通过对新疆地区不明原因发热人群血清Tahyna病毒抗体进行检测,以了解Tahyna病毒在当地的感染状况及分布特征。通过间接免疫荧光方法对新疆维吾尔自治区南部喀什地区、北部伊犁地区742例不明原因发热患者急性期血清标本进行Tahyna病毒抗体检测,并对IgM抗体阳性标本平行进行Tahyna病毒、Snowshoe hare病毒和Inkoo病毒三种抗原性相似的布尼亚病毒的蚀斑减少中和试验。研究结果显示新疆南部喀什地区采集不明原因发热患者急性期血清中,IgM抗体阳性率5.3%,IgG抗体阳性率18.3%;新疆北部伊犁地区采集的急性期患者血清标本中并未发现TAHV IgM抗体阳性;蚀斑减少中和试验结果显示,TAHV IgM抗体阳性患者血清中Tahyna病毒中和抗体滴度较其它两种布尼亚病毒中和抗体滴度升高明显。本研究证实新疆南部地区不明原因发热人群存在Tahyna病毒的急性感染和既往感染,为相关疾病的进一步监测提供基础。     

用反向被动血凝及血凝抑制方法检测流行性出血热病毒抗原和抗体

本文建立了检测流行性出血热病毒(EHFV)液体抗原及抗体的反向被动血凝(RPHA)和血凝抑制(RPHI)方法,RPHA检测EHFV抗原的敏感性与ELISA相近;RPHI检测EHFV抗体与IFA的符合率为97.3％,敏感性略低。     

流行性出血热病毒在Vero一E6细胞内引起细胞病变作用的新发现

自McCormick等发现Vero-E6细胞对流行性出血热病毒的敏感性后,国内外已有不少学者应用该细胞进行病毒分离和试验研究,但均未发现病毒在该细胞内规律性病变。病毒的存在和滴度只能按免疫荧光法(IFA)证实和测出。本文应用我国分离的出血热病毒在Vero-E6细胞上培养和观察,发现病毒在该细胞上出现有规律的病变并能测出病毒滴度,病变能被特异性中和抗体中和。现将结果报道如下。     

长爪沙鼠腹腔巨噬细胞对流行性出血热病毒的敏感性

本文就长爪沙鼠腹腔巨噬细胞(MΦ)对流行性出血热病毒(EHFV)的敏感性进行了试验,用3株野鼠型(A9、R3、76-118)和1株家鼠型EHFV(R22),并用对EHFV敏感的Vero-E6细胞作对照,结果沙鼠腹腔巨噬细胞感染EHFV后,第1代第8天前即可查见明显的特异性荧光,第16天左右达高峰,病毒滴度≥10~(-7.5),与Vero-E6细胞比较,培养上清液的病毒滴度,沙鼠MΦ较Vero-E6细胞高1～4个对数,当感染病毒量很低时,在Vero-E6细胞内测不出特异性抗原,而在沙鼠MΦ内病毒仍可繁殖,滴度达10~(-5.(?)),中和试验、间接免疫荧光检测和荧光阻断试验均证明,沙鼠MΦ内繁殖的病毒确实为EHFV。     

小牛血清对鸡传染性法氏囊病病毒增殖的抑制机制

本试验研究了小牛血清(CS)对法氏囊炎病毒(IBDV)蚀斑形成的抑制机制。CS与鸡胚细胞(CEF)作用后,CS中的抑制因子能被细胞吸收。这说明血清中的抑制因子可附着在CEF上。细胞预先用CS处理,则吸附病毒的能力明显降低。还发现,若把CS加入琼脂培养液中,则能抑制IBDV的蚀斑形成。这说明CS能抑制病毒对其周围细胞的感染。CS对IBDV蚀斑形成的抑制机制,不是由于抑制因子直接中和了病毒,而是因为抑制因子附着在细胞表面,占据了细胞的病毒受体,从而阻止了病毒附着于细咆,以致抑制了病毒蚀斑的形成。     

狂犬病毒蚀斑方法的建立

我们用CTN-1狂犬病毒二倍作细胞适应株[1]经蚀斑纯化而获得的CTN-2病毒株在BHK-21单层细胞培养建立了狂犬病毒的简易蚀斑技术。用连续10倍稀释的病毒悬液接种BHK-21细胞而产生的蚀斑数呈10倍规律的减少。该蚀斑技术用于蚀斑减少中和试验测定不同国际单位(IU)效价的抗狂犬病血清与原抗血清(IU)效价均高低成正比。用蚀斑中和试验测定了七批我国生产的人用精制抗狂犬病血清的IU效价与原抗血清IU效价的高低是相符的。     

应用反向间接血凝法早期诊断流行性出血热

1985年我们研制了流行性出血热(EHF)抗体致敏的诊断血球,建立了检测EHF抗原的R-PHA方法。用此法检测本所分离的EHF病毒株感染的VeroE_6细胞培养上清液,以及人工感染EHFV的小白鼠乳鼠脑悬液等,均获得良好结果。以后又应用此法检测了EHF早期病人血清、白细胞冻融液及人工感染EHFV的小白鼠乳鼠血清等,并作了特异的EHF抗体阻断试验,现将结果报告如下:     

应用微量细胞病变中和试验法(MCPENT)对我国EHF病毒株和病人血清进行血清分型

本文应用微量细胞病变中和试验(MCPENT)对我国22株不同来源的流行性出血热病毒(EHFV)进行血清分型研究结果除一株具有广谱抗原性外,所有毒株均可准确地被分为血清1型和血清2型,其分型结果与用空斑减少中和试验(PRNT)完全一致。此外,MCPENT法还能对不同流行区EHF病人血清进行分型诊断。此法简便、经济、准确可靠,便于推广应用。     

流行性出血热病毒单克隆抗体的特性鉴定及其对病毒结构蛋白作用的初步研究

本文运用放射免疫沉淀法(RIP)、Western-blot及ELSA夹心法,对一组针对流行性出血热病毒(EHFV)L99株、C4株的单克隆抗体(McAb)进行特性鉴定,其中4株McAb针对糖蛋白G2,29株针对核壳蛋白(NP),1株针对糖蛋白G1和NP。微量中和试验和血凝抑制(HI)试验分析表明,虽绝大多数抗NP McAb既无中和活性亦无HI活性,但有1株例外。具有明显的中和活性和HI活性,提示EHFV核壳蛋白上可能存在中和抗原和血凝抗原决定簇。2株抗G2 McAb具有较高的HI活性,1株抗G2 McAb有较低的中和活性和较高的HI活性,另一株抗G2 McAb仅具有中和活性,表明EHFV糖蛋白G2上存在独立的中和与血凝抗原决定簇,也可能存在具有中和、血凝双重功能的决定簇。竞争ELISA分析显示。G2蛋白上某些中和位点和血凝位点虽然独立分布,但在某一区域可能相当靠近或有部分重叠。     

Analysis of single Alzheimer solid plaque cores by laser capture microscopy and nanoelectrospray/tandem mass spectrometry

Aggregation of the 40-42 residue amyloid beta-peptide (Abeta) into amyloid plaques is a central event in Alzheimer's disease (AD) pathogenesis. Many proteins have by immunohistochemical techniques been shown to codeposit with Abeta in AD plaques. It is possible that some of these could seed Abeta aggregation and therefore be found in the actual core of the plaque. Here, we present a highly sensitive method for unbiased biochemical analysis of plaque cores. A mild purification protocol based on centrifugation and filtration was used to purify intact plaque cores from human AD brain. The purified plaques were dispensed on a glass slide and viewed in a laser capture microscope, and plaque cores were catapulted into a tube cap by a laser beam. After dissolution in formic acid, plaques were digested and analyzed by liquid chromatography coupled online to electrospray/tandem mass spectrometry. One single plaque was found to be sufficient for positive identification of the main amyloid component. Remarkably, Abeta was the only protein identified when 200 plaques were isolated and analyzed with the present method. Thus, it is possible that no proteins copolymerize with Abeta in the plaque cores and that Abeta alone is sufficient for formation of plaque cores. In support of this notion, core-like structures were observed after incubation of synthetic Abeta for 2 weeks. We suggest that the method described here could be used for the general analysis of amyloid aggregates and inclusion bodies found in other neurodegenerative disorders and that plaque cores in AD brain are molecularly homogeneous structures.     

流行性出血热病毒感染NIH裸鼠免疫组织化学研究

流行性出血热病毒（ＥｐｉｄｅｍｉｃＨｅｍｏｒｒｈａｇｉｃＦｅｖｅｒｖｉｒｕｓ,ＥＨＦＶ）感染ＮＩＨ裸鼠后,濒死状态取材,应用免疫组织化学方法（ＡＢＣ）检测各组织中的特异性病毒抗原。结果表明,ＮＩＨ裸鼠对ＥＨＦＶ感染敏感,感染后其脑、肺、肝、肾和心脏组织实质细胞浆内均可检出特异性抗原。     

流行性出血热病毒在人革膜传代细胞内的生长繁殖

本文应用人羊膜传代细胞(Wish细胞)对流行性出血热病毒(EHFV)的敏感性进行了试验,用EHFV武株及76118、A9、R22、R4、陈株等5个代表株接种Wish细胞。结果Wish细胞感染EHFV后第1代第8～10天即可查见明显的特异性荧光,荧光光强度随代数和时间而增加,TCID50为10~4～/10~5ml。并用荧光阻断试验和双份血清证实在Wish细胞内繁殖的病毒为EHFV。此结果为EHF病原学研究提供了新的敏感细胞株。     

斑点杂交生物素法检测流行性出血热病毒RNA

为寻找一种用于检测流行性出血热病毒的分子杂交方法,以生物素-7-dATP标记流行性出血热病毒(EHFV)R_(22)株M片段的cDNAR_3克隆作探针,与人源性的EHFVH-114、H-435株RNA基因组进行斑点杂交,得到阳性结果,可检出5pg的cDNA或RNA。此探针与疱疹病毒DNA不出现杂交信号。以上结果说明这种标记探针具有EHFV特异性,可以扩大应用范围,结果还表明动物源性和人源性EHFV均具有共同的保守核苷酸序列。     

Properties of Venezuelan Equine Encephalomyelitis Virus Accompanying Attenuation In Vitro

Virus obtained during serial plaque passage of the virulent parent egg seed (PES) of the Trinidad strain of Venezuelan equine encephalomyelitis (VEE) virus produced only large plaques during either 3 serial plaque passages in chick fibroblasts or 10 plaque passages in L cells, and was lethal for mice by the intraperitoneal route. Virus showing these characteristics was designated the stable large-plaque (Ls) type. In contrast, virus obtained during serial plaque passage of the attenuated 9t strain in chick fibroblasts formed only very small plaques and was not lethal for mice by the intraperitoneal route. Virus showing these properties was designated the stable small-plaque (Ss) type. Under other passage conditions, however, large-plaque virus that yielded about 90% large and 10% small plaques was obtained; this virus was designated the unstable large or Lu type because it differed from the Ls type, which yielded only large plaques. The Lu type continued to yield the same ratio of large to small plaques for several plaque-to-plaque passages. In addition, small-plaque virus that yielded both large and small plaques and that showed a reduced capability to infect mice was also recovered. This virus was designated the unstable small or Su type because it differed from the Ss type in its higher level of virulence and in its plaque-forming properties. Thus, based upon the properties of virulence for mice and plaque size, four viral types could be discerned. The evidence suggests that serial passage in cell culture imposed environmental pressures that sequentially selected the following viral types: Ls, Lu, Su, and Ss.     

Compressive mechanical properties of atherosclerotic plaques—Indentation test to characterise the local anisotropic behaviour

Accurate material models and associated parameters of atherosclerotic plaques are crucial for reliable biomechanical plaque prediction models. These biomechanical models have the potential to increase our understanding of plaque progression and failure, possibly improving risk assessment of plaque rupture, which is the main cause of ischaemic strokes and myocardial infarction. However, experimental biomechanical data on atherosclerotic plaque tissue is scarce and shows a high variability. In addition, most of the biomechanical models assume isotropic behaviour of plaque tissue, which is a general over-simplification. This review discusses the past and the current literature that focus on mechanical properties of plaque derived from compression experiments, using unconfined compression, micro-indentation or nano-indentation. Results will be discussed and the techniques will be mutually compared. Thereafter, an in-house developed indentation method combined with an inverse finite element method is introduced, allowing analysis of the local anisotropic mechanical properties of atherosclerotic plaques. The advantages and limitations of this method will be evaluated and compared to other methods reported in literature.     

Plaque Size Heterogeneity: a Genetic Trait of Lymphocytic Choriomeningitis Virus

All of the ten strains of lymphocytic choriomeningitis virus assayed on BHK 21/13S cells showed various degrees of plaque size heterogeneity. The amount of virus released from these plaques was usually very small because of rapid photodynamic inactivation by neutral red. When virus from large and small plaques of a specific strain was plated, the same distribution of plaque size was obtained from each clone. Although it was shown that surface virus could possibly be randomly distributed at the time of addition of neutral red overlays, no virus could be isolated from nonplaque areas. Two different strains of virus (CA1371 and WE) with markedly different plaque size ranges were separated by plaque excision from plates infected with a mixture of both viruses.     

Separation of Plaque-type Variants of Encephalomyocarditis Virus by Chromatography on Calcium Phosphate

Encephalomyocarditis (EMC) virus (K-2 strain) was separated into two distinct peaks of optical density by chromatography on calcium phosphate, eluting at 0.17 and 0.31 m, respectively. The virus in these peaks could not be distinguished by infectivity (plaque-forming units), hemagglutinin activity, electron microscopic appearance, sedimentation coefficient, or base ratios. However, variants producing large plaques predominated in the first peak eluted, whereas variants producing small plaques were concentrated in the second peak. When plaque-purified large and small plaque variants were chromatographed individually, each gave a single peak eluting at 0.16 and at 0.43 m, respectively. However, one small plaque type isolated was eluted in the 0.17 m region expected for large plaque variants, and not with the bulk of the small plaque variants. There were indications that EMC virus (K-2 strain) could be separated into more than two peaks by use of selected elution gradients. The possibility that there may be a relationship between plaque size and point of elution from calcium phosphate is discussed.     

流行性出血热(EHF)病毒半微量甲基纤维素空斑法的建立

本文报道EHF病毒一种新的空斑形成按术,即半微量甲基纤维素空斑法的建立及其应用。6株来源不同的毒株均可在V_(ero)-E_6细胞或V_(ero)细胞上形成清晰的空斑,形成的空斑能被特异抗EHF病毒血清所中和。其敏感性与用琼脂糖作覆盖物的空斑法一致。该法具有操作简便、快速等优点,适用于EHF的病原学和血清学研究。