关键词： VIRUS RECEPTOR   VIRAL ATTACHMENT SITE   IMMUNOGLOBULIN-LIKE DOMAINS  

摘要： Mouse fibroblast cell lines were transfected with truncated forms of the human poliovirus receptor (PVR) cDNA and tested for the expression of functional receptors for poliovirus. Several receptor constructs, all containing the coding region of the first 143 amino acids of PVR, were able to render mouse cells susceptible to poliovirus infection. A deletion of 65 amino acids in the first extracellular domain of PVR prevented virus attachment and infection. These data suggest that domain 1 is necessary and sufficient for the virus-receptor interaction. A PVR/intercellular adhesion molecule 1 hybrid receptor, expressing the PVR variable domain on a truncated receptor molecule for human rhinovirus 14, was shown to be a functional receptor for poliovirus. This observation indicates that, subsequent to attachment to the PVR-binding domain, poliovirus can use the same pathway as the major receptor group rhinoviruses to enter cells.

关键词： TRUNCATED RECEPTORS   MOUSE L-CELL TRANSFORMANTS   VIRUS BINDING SITE   CYTOPLASMIC DOMAIN   MONOCLONAL ANTIBODIES AGAINST RECEPTOR  

摘要： A number of mutant cDNAs of the human poliovirus receptor were constructed to identify essential regions of the molecule as the receptor. All mutant cDNAs carrying the sequence coding for the entire N-terminal immunoglobulin-like domain (domain I) confer permissiveness for poliovirus to mouse L cells, but a mutant cDNA lacking the sequence for domain I does not. The transformants permissive for poliovirus were able to bind the virus and were also recognized by monoclonal antibody D171, which competes with poliovirus for the cellular receptor. These results strongly suggest that the poliovirus binding site resides in domain I of the receptor. Mutant cDNAs for the sequence encoding the intracellular peptide were also constructed and expressed in mouse L cells. Susceptibility of these cells to poliovirus revealed that the entire putative cytoplasmic domain is not essential for virus infection. Thus, the cytoplasmic domain of the molecule appears not to play a role in the penetration of poliovirus.

关键词： ATOMIC STRUCTURE   HOST RANGE   POLIOVIRUS   RECEPTOR  

摘要： The inability of certain poliovirus strains to infect mice can be overcome by the expression of human poliovirus receptors in mice or by the presence of a particular amino acid sequence of the B-C loop of the viral capsid protein VP1. We have identified changes in an additional capsid structure that permit host-restricted poliovirus strains to infect mice. Variants of the mouse-virulent P2/Lansing strain were constructed containing amino acid changes, deletions and insertions in the B-C loop of VP1. These variants were attenuated in mice, demonstrating the importance of the B-C loop sequence in host range. Passage of two of the B-C loop variants in mice led to the selection of viruses that were substantially more virulent. The increased neurovirulence of these strains was mapped to two different suppressor mutations in the N-terminus of VP1. Whereas the B-C loop of VP1 is highly exposed on the surface of the capsid, near the five-fold axis of symmetry, the suppressor mutations are in the interior of the virion, near the three-fold axis. Introduction of the suppressor mutations into the genome of the mouse-avirulent P1/Mahoney strain resulted in neurovirulent viruses, demonstrating that the P2/Lansing B-C loop sequence is not required to infect mice. Because the internal host range determinants are in a structure known to be important in conformational transitions of the virion, the host range of poliovirus may be determined by the ability of virions to undergo transitions catalyzed by cell receptors.

关键词： 自发性肿瘤   非人灵长类   脊髓灰质炎疫苗   肿瘤学   灵长类动物   上皮性肿瘤   文献综述   无性细胞瘤   恶性淋巴瘤   腺瘤性息肉  

摘要： 本文综述了世界文献中记载的非人灵长类共783例自发性肿瘤,这些肿瘤都与人类相似。最常见报导的是癌,老龄个体中多发,也与人类相似。狒狒和猕猴的肿瘤报道比其它灵长类多,消化系统受到肿瘤侵袭更普遍。尽管在动物园、灵长类中心、各研究中心和脊髓灰质炎疫苗制品实验室中畜养成千上万的灵长类动物,但有关肿瘤病例却报道甚少,这是由于关养的猴都比较年轻的缘故。以1968年为例,猴自发性肿瘤病例的报道仅有122例。此后,全世界各研究所报道的猴数累计为783例。

关键词： 脊髓灰质炎病毒   重组痘苗病毒基因表达  

摘要： 含脊髓灰质炎病毒1型(简称 PV1)全基因7.4Kb cDNA 和编码 PV1外壳蛋白 VP12.5Kb 的 cDNA 片段的两株重组痘苗病毒(RV-1和 RV-2)表达了 PV1抗原。经荧光标记的抗 PV1型特异性单克隆抗体检测,感染了 RV-1和 RV-2的 Herp-2细胞呈阳性荧光反应。免疫印迹实验证实两株重组痘苗病毒分别表达 PV1抗原三条和两条特异性蛋白带。免疫家兔后能诱导产生抗 PV1中和抗体。本文对重组病毒表达 PV1抗原的效率进行了初步讨论。

关键词： 脊髓灰质炎   病毒   聚合酶链反应  

摘要： 利用聚合酶链反应(Polymerase chian reaction,PCR)对脊髓灰质炎病毒Sabin相关株进行了诊断和定型。选用的引物Map7、Map14与肠道病毒具有同源性,经扩增后产生大小为115bp的核酸片段;引物Sabin Ⅰ-1、Ⅰ-2对Ⅰ型Sabin株特异,经扩增后产生大小为97bp的核酸片段;引物Sabin Ⅱ-1、Ⅱ-2对Sabin Ⅱ型株特异,扩增产物为71bp;引物Sa-bin Ⅲ-1、Ⅲ-2对Sabin Ⅲ型株特异,扩增产物为44bp.此方法敏感性高,可检出10^(1.5)TCID_(50)/ml感染量的病毒核酸。利用PCR方法对我国各地送检的几株脊髓灰质炎病毒的定型结果,与中和试验完全一致。

关键词： 脊髓灰质炎   ELISA   病毒   IgM抗体  

摘要： 用酶联免疫吸附测定(ELISA)法测定抗脊髓灰质炎(脊灰炎)病毒IgM抗体对脊灰炎的早期诊断、预防和控制具有重要的应用价值。现将我们应用ELISA法对174例患者的抗脊灰炎病毒IgM抗体的检验情况报告如下。

摘要： Based on predictions of the structure of proteinase 3C of poliovirus, mutations have been made at residues that are supposed to constitute the catalytic triad. Wild-type and mutant 3C were expressed in Escherichia coli, purified to homogeneity, and characterized by the ability to cleave a synthetic peptide substrate or an in vitro translated polypeptide consisting of part of the polyprotein of poliovirus. Additionally, the ability of autocatalytic processing of a precursor harboring wild-type or mutant 3C sequences was tested. Single substitutions of the residues His-40, Glu-71, and Cys-147 by Tyr, Gln, and Ser, respectively, resulted in an inactive enzyme. Replacement of Asp-85 by Asn resulted in an enzyme that was as active as wild-type enzyme in trans cleavage assays but whose autoprocessing ability was impaired. Our results are consistent with the proposal that residues His-40, Glu-71, and Cys-147 constitute the catalytic triad of poliovirus 3C proteinase. Furthermore, residue Asp-85 is not required for proper proteolytic activity despite being highly conserved between different picornaviruses. This indicates that Asp-85 might be involved in a different function of 3C.

关键词： 实验动物   动物权利   动物研究   遭受痛苦   生物医学   猴子   人和动物   脊髓灰质炎疫苗   物自身   发病数  

摘要： 当人类社会享受着现代医学带来的巨大益处时,当每个病魔缠身的病人康复后微笑着面对新的生活时,我们可能很少想到或者几乎没想到这些成果中也有实验动物的巨大功勋。如果没有生物医学实验动物的奉献,今天人们的生活、科学的进展可能会完全是另一番面貌。 从以下一些数据中我们对生物医学实验动物的情况可以略见一斑。据中国卫生年鉴统计。

关键词： 脊髓灰质炎疫苗   家庭护理   基础免疫   肠道吸收   接种部位   麻疹疫苗   百白破三联疫苗   百白破疫苗   减毒   全程注射  

摘要： 1.卡介苗卡介苗是一种活菌苗,出生后即可接种,接种部位在3～4周后出现红肿、溃疡,结痂后逐渐痊愈。接种后2天不能洗澡,不要用手去抓。 2.脊髓灰质炎疫苗于出生2个月,3个月、4个月完成基础免疫,在2岁后进行一次加强免疫。因脊髓灰质炎疫苗经肠道吸收,故服药后至少30分钟内不要喂奶以免呕吐。