关键词： ALGINATE   ENCAPSULATION   ENTRAPMENT   VERO CELLS   POLIOVIRUS  

摘要： Obligatory anchorage dependant Vero cells were successfully grown in gelatinous-like macrocarriers made of calcium alginate. Entrapped single cells were immobilized within the polymerized alginate matrix divide to form large spherical clumps of cells. A cell density of 17 x 10(6) cells/ml of alginate with over 95% viability was obtained after 14 days in spinner flasks. When subjected of poliovirus type I infection, spherical masses of Vero cells progressively showed extensive cytopathic effect but remained entrapped in the alginate matrix of the macrocarriers. Virus was released into a cellular debris free-like supernatant and reached a peak titer of 10(8.0) TCID50/ml after 72 hours.

关键词： Antibodies   Diarrhea   Poliovirus   Enzyme linked immunosorbent assay   Oral poliovirus vaccines   Infants   Age groups   Poliomyelitis   Inactivated poliovirus vaccines  

摘要： Fifteen cases of type 1 paralytic poliomyelitis occurred in August 1988, mainly among young adults in the Jewish population of Israel, where vaccine coverage exceeds 90%. The military forces, as a precaution against further spread of the virus, vaccinated all recruits in late September. They received oral poliovirus vaccine (OPV) simultaneously with prophylactic immune serum globulin (ISG) to protect against hepatitis A virus infection. Since it is generally not recommended to administer live vaccines simultaneously with ISG, the serologic response to OPV given at the same time as ISG was compared with the response when OPV was given alone;specimens were also available from a control group receiving ISG alone. No effect of ISG on the antibody response to OPV was found, and thus there appears to be no contraindication to giving OPV at the same time as injecting pooled ISG-particularly relevant for travelers to areas endemic for both diseases, who have to leave at short notice. Of recruits 18-19 years of age, 21% lacked antibodies to type 1 poliovirus, suggesting either a decline in antibody titers with age or a lack of vaccine potency during earlier years. After the booster, only 2% lacked type 1 antibody, and the geometric mean titer increased from 1:16 to 1:698.

关键词： Alternative splicing   Cellular receptor   Poliovirus   Secreted form  

摘要： Both genomic and complementary DNA clones encoding poliovirus receptors were isolated from genomic and complementary DNA libraries prepared from HeLa S3 cells, respectively. Nucleotide sequence analysis of these cloned DNAs revealed that the poliovirus receptor gene is .apprx. 20 kb long and contains seven introns in the coding region, and that at least four mRNA isoforms referring to the coding sequence are generated by alternative splicing and appear to encode four different molecules, that is, ***., ***., ***. ***.. The predicted amino acid sequences indicate that ***. and ***., corresponding to the previously described cDNA clones H20A and H20B, respectively, are integral membrane proteins while the other two molecules described here for the first time lack a putative transmembrane domain. Mouse cell transformants carrying ***. were permissive for poliovirus infection, but those carrying ***. were hardly permissive. In contrast to ***., ***. was not detected on the surface of the mouse cell transformants but was detected in the culture fluid by an immunological method using a monoclonal antibody against poliovirus receptor. Three types of splicing products for ***., ***. and ***. were detected by polymerase chain reactions using appropriate primers in poly(A)+ RNAs of the brain, leukocyte, liver, lung and placenta of humans;the choice of primers used did not permit detection of ***.. In situ hybridization using a cDNA fragment as a probe demonstrated that the PVR gene is located at the band q13.1 .fwdarw. q13.2 of human chromosome 19.

关键词： Poliomyelitis   Seroepidemiology   Neutralizing antibody  

摘要： In order to study the serological status of a population against poliomyelitis, neutralizing antibody for the three types of polioviruses were examined in 742 serum specimens from individuals aged from 1 to 70 years and over were collected during 1985. Sixty-two percent of the sera had antibodies (titre .gtoreq. 1:8) to all three polioviruses, while 5% had no poliovirus antibody at all. However the rates of seropositivity did vary with age: the 10-19 age group had the lowest frequency of antibody (38%) to the three viruses and the difference between the percentage of this group and the previous (1-10 years) and following ones (20-70 years and over) was highly significant. The results of this seroprevalence survey indicate a gap in immunity to poliomyelitis in the population examined.

关键词： 抗原分析单克隆抗体   脊髓灰质炎病毒  

摘要： 本文报告利用6个中和性单克隆抗体对广东省1985～1988年的59株PolioⅠ型病毒进行抗原分析。结果59株病毒共有5种不同的排列,其中以P_I—3、P_I—4和P_I—5排列的毒株占多数,分别为近年本省大陆地区和海南儋县脊髓灰质炎流行的流行株,它们之间的抗原性差异较大。

摘要： HIV infection is known to impair both cellular and humoral immunity. The antibody levels to poliovirus were measured in 17 HIV-infected and 3 HIV-seronegative homosexual men before and after vaccination with enhanced inactivated poliovirus vaccine (eIPV). The subjects were tested for neutralizing antibodies to poliovirus types 1, 2, and 3;the number of peripheral blood T4 cells and lymphocyte responses after stimulation with phytohemagglutinin, concanavalin A, and pokeweed mitogen were measured. Before vaccination, all subjects demonstrated neutralizing antibodies to the three types of poliovirus. After eIPV administration, a rise in anti-poliovirus antibody titer was noted in subjects whose T4 cell count was > 200/ml, whereas the group with low T4 cell counts failed to respond. The response to eIPV immunization correlated with the number of circulating T4 cells and the mitogen-induced lymphocyte stimulation index.

关键词： 脊髓灰质炎   病毒   合成肽   免疫诱  

摘要： 本文报道了模拟脊髓灰质类Ⅰ型病毒Mahoney株外壳蛋白的氨基酸顺序,用化学方法合成了位于VP1 70～75、95～102、93～103、70～75+93～103和VP 3132～143的五段肽。合成的肽段与载体蛋白偶联后免疫家兎能产生明显的免疫记忆作用。结果表明这些合成肽均能被脊髓灰质炎多克隆抗血清所识别,具有一定的免疫原性。

关键词： Phospholipid synthesis   Poliovirus   Rna replication  

摘要： Poliovirus infection leads to an increase of phospholipid synthesis and the proliferation of new membranes, giving rise to a great number of cytoplasmic vesicles in the infected cells. Viral RNA replication is physically associated with these newly-synthesized membranes. Cerulenin, an inhibitor of lipid biosynthesis, effectively blocks the growth of poliovirus in HeLa cells. The presence of cerulenin after virus entry prevents the synthesis of poliovirus proteins. However, if this antibiotic is added at later stages of the virus replication cycle, it has no effect on viral translation itself, nor on the proteolytic processing and myristoylation of poliovirus proteins. The synthesis of viral, but not cellular RNA is selectively inhibited by cerulenin. Analysis of the viral RNA made in poliovirus-infected cells by specific minus-or plus-stranded RNA probes suggests a selective blockade by cerulenin of plus-strand RNA synthesis. Finally, the synthesis of phospholipids and the proliferation of membranes does not take place if cerulenin is added to the culture medium. These findings indicate that continuous phospholipid synthesis is required for efficient poliovirus genome replication and provide new insights towards the understanding of the molecular events that occur during poliovirus growth.

摘要： Poliovirus infection of HeLa cells results in cleavage of the p220 subunit of eukaryotic initiation factor eIF-4F and inhibits cap-dependent initiation of protein synthesis. To examine the effect of virus-induced inhibition on the structure of initiation factor complexes involved in cap binding, the polypeptide compositions of cap affinity-purified complexes from uninfected and poliovirus-infected HeLa cells were analyzed. Monoclonal antibodies directed against p220 and an eIF-3 subunit, p170, were utilized to locate eIF-3 eIF-4F on sucrose gradients and in fractions eluting from cap analog columns. This approach resulted in the purification of several different cap-binding complexes from different cellular subfractions and revealed significant differences in their composition after infection. The results indicate that eIF-3 and eIF-4F bind to th cap structure, possibly in the form of a complex, and that a modified form of eIF-3 alone has some capbinding activity in the complete absence of p220, eIF-4A, and eIF-4E. Ribosome-derived complexes containing cleaved p220 are no longer associated with eIF-3 or eIF-4A, and a significant amount of cleaved p220 is associated with a unique cytoplasmic cap-binding complex. The cytoplasmic complex also contains Mr = 170,000 and 80,000 polyeptides, neither of which are major components of eIF-4F. These results demonstrate significant variation in the composition of cap-binding complexes from both infected and uninfected cells. They indicate that eIF-3 might play a direct role in cap binding and suggest that poliovirus-induced cleavage of p220 results in the release of the eIF-4A subunit from eIF-4F and abolishes an association between eIF-4F and eIF-3 which may function during the multifactor steps involved in initiation of cap-mediated translation.