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sindbis virus mutants selected for rapid growth in cell culture display attenuated virulence in animals.mutants of sindbis virus were selected for rapid growth in baby hamster kidney (bhk) cell cultures and screened for attenuation of virulence in suckling mice. comparisons among independently isolated virulent and attenuated strains, as well as a classical reversion analysis, showed that accelerated penetration of bhk cells was correlated with attenuation in vivo. both phenotypic changes resulted from a reorganization of virion structure as detected by monoclonal antibodies. these results suggest ...19846204381
isolation of karelian fever agent from aedes communis mosquitoes. 19846147473
ockelbo disease in sweden: epidemiological, clinical, and virological data from the 1982 outbreak.an outbreak of ockelbo disease, a syndrome with rash, arthralgia and moderate fever reactions, which occurred in sweden 1982 is described. a virus, designated edsbyn 5/82, isolated from mosquitoes and closely related to sindbis virus (togaviridae: alphavirus) is the probable etiologic agent. sixty-five patients with typical clinical manifestations of the disease became ill in august 1982 and exhibited antibody titer rises against both edsbyn 5/82 and sindbis viruses by indirect immunofluorescenc ...19846150654
association of a sindbis-like virus with ockelbo disease in sweden.an alphavirus isolated from culiseta mosquitoes has been associated with ockelbo disease, an exanthema arthralgia syndrome occurring in sweden. the isolate was made from mosquitoes collected in edsbyn (central sweden), an area with considerable ockelbo disease morbidity. this isolate proved to be indistinguishable from sindbis virus by complement-fixation and hemagglutination-inhibition tests, and was antigenically related to sindbis in plaque reduction neutralization tests. patients with ockelb ...19846150655
disparate response of encephalomyocarditis virus and mm virus to interferon in jls-v9r cells.jls-v9r cells, a balb/c mouse bone marrow cell line chronically infected with rauscher leukemia virus, were treated with mouse interferon and inoculated with several different lytic viruses. relatively low interferon concentrations protected the cells against sindbis virus, vesicular stomatitis virus and mm virus. in contrast, encephalomyocarditis virus replication was inhibited by less than 1 log even with an interferon concentration of 1000 u/ml. these findings provide further evidence that in ...19846099710
[effect of virazole on the antiviral activity of poly(g) x poly(c) and other polyribonucleotide interferonogens].the effect of virazole on the antiviral activity of poly (g) x poly (c), poly (g, a) x x poly (c) and poly(g, i) x poly (c) was studied in cell cultures and on mice. it was shown that virazole in concentrations not sufficient for significant inhibition of the development of vesicular stomatitis virus or sindbis virus in chick embryo cell cultures markedly increased the antiviral effect and allowed decreasing the minimum effective doses of the synthetic polyribonucleotide complexes with respect t ...19846089650
rubella virus-induced interference in chick embryo cells.primary chick embryo cells inoculated with rubella virus were found to develop interference with the multiplication of sindbis virus. substantial quantities of interferon (ifn) were detectable in the cell cultures indicating that the resistance induced was due to ifn production.19846084951
arbovirus infections in humans in new south wales. seroepidemiology of the alphavirus group of togaviruses.a seroepidemiological study of the prevalence of antibodies to alphaviruses (ross river [rrv], sindbis [sin] and getah [get] viruses) was carried out on 16 842 specimens of sera collected during 1981 and 1982 from individuals of all ages living in all health regions of new south wales. prevalence rates were found to be low in the major coastal cities of sydney, newcastle and wollongong, and in the whole of the tablelands. in coastal populations, the rates were highest in the far and mid north co ...19846094993
interferon-induced transfer of viral resistance by human b and t lymphocytes.enriched human b lymphocytes cocultivated with mouse l cells produced human leukocyte interferon (ifn-alpha) and shortly thereafter transferred antiviral activity to the recipient cells (99% inhibition of expected virus yield). in contrast, cocultivation of enriched t-cell populations with mouse l cells resulted in no ifn production or transfer of antiviral activity. in addition, both t and b lymphocytes pretreated with exogenous ifn or stimulated in vitro by mitogens could transfer antiviral ac ...19846088090
venereal transmission of sindbis virus between individuals of aedes australis (diptera: culicidae). 19846748004
biochemical studies of the maturation of the small sindbis virus glycoprotein e3.a small glycoprotein (e3) was purified from the culture fluid of sindbis virus-infected primary chick embryo fibroblasts. tryptic peptide mapping and pulse-chase studies verified that this protein was produced as a by-product of the cleavage of the precursor protein pe2 to produce the envelope glycoprotein e2. a 2600-fold purification was achieved via a procedure which used differential ethanol precipitation, gel filtration, ion-exchange chromatography, and affinity chromatography on a lentil le ...19846443592
[combined antiviral effect of synthetic polyribonucleotide interferonogens and specific antiviral antibodies in arbovirus infections].a model of tick-borne encephalitis in balb/c mice was used to investigate the protective anti-viral effect of an interferon inducer, poly(g).poly(c), and specific gamma-globulin administered to the animals together or separately in small doses 24 hours before or after virus inoculation. administration to the animals of poly(g).poly(c) alone or gamma-globulin alone was shown to produce a poor protective effect. simultaneous administration of both preparations resulted in a significant decrease of ...19846464427
a single mutation in chinese hamster ovary cells impairs both golgi and endosomal functions.a chinese hamster ovary cell mutant dtg 1-5-4, was selected for pleiotropic defects in receptor-mediated endocytosis by methods previously described (robbins, a. r., s. s. peng, and j. l. marshall, 1983, j. cell biol., 96:1064-1071). dtg 1-5-4 exhibited increased resistance to modeccin, pseudomonas toxin, diphtheria toxin, sindbis virus, and vesicular stomatitis virus, as well as decreased uptake via the mannose 6-phosphate receptor. fluorescein-dextran-labeled endosomes isolated from dtg 1-5-4 ...19846480694
evidence for a change in capsid morphology during sindbis virus envelopment.sindbis virus nucleocapsids were isolated from intact virus particles and from the cytoplasms of infected cells. these two isolates of purified nucleocapsids differed from one another in ribonuclease sensitivity and in sedimentation velocity. these findings suggest that a conformational change takes place in the sindbis virus nucleocapsid during envelopment.19846543412
identification of a transfer of viral core protein to cellular ribosomes during the early stages of alphavirus infection.sindbis virus containing [35s]methionine-labeled structural proteins was allowed to be taken up by primary chick embryo fibroblasts, and the fate of the core protein was studied. the experiments show that core protein of incoming viral particles is transferred to the large subunit of cellular ribosomes during the initial steps of virus infection. a similar transfer occurs in vitro if cores isolated from sin virus particles are incubated in the postmitochondrial cytoplasmic fraction of cell lysat ...19846545074
heterogeneity of sindbis virus glycoprotein e1 and its modification by host cell transformation.the electrophoretic properties of glycoprotein e1 of sindbis virus grown in rous sarcoma virus-transformed cells were compared with those of sindbis virus grown in untransformed cells. isoelectric focusing in a gel containing 9.5 m-urea and 2% nonidet p40 indicated that the glycoprotein e1 of sindbis virus from the untransformed cells was electrochemically heterogeneous and consisted of four components, whose isoelectric points (pis) ranged from 6.2 to 6.7; the e1 of sindbis virus from the trans ...19846319579
[induction of alphavirus ts-mutations by n-methyl-n-nitro-n-nitrosoguanidine added to the replicating virus].the possibility of producing ts mutants of sindbis and eastern equine encephalomyelitis (eee) virus by treatment of replicating virus with n-methyl-n-nitro-n-nitrosoguanidine was studied. n-methyl-n-nitro-n-nitrosoguanidine added in a concentration of 20 micrograms/ml to chick fibroblast cultures infected with sindbis virus for 4 hours was shown to induce ts mutations in the virus. under similar conditions no ts mutants of eee virus could be obtained. the content of ts mutants in the mutagenized ...19846324493
identification of immunologically cross-reactive proteins of sindbis virus: evidence for unique conformation of e1 glycoprotein from infected cells.hyperimmune antisera to purified sindbis (sin) or semliki forest (sf) virus were used to identify alphavirus-specific and cross-reactive proteins in virions and infected cells. the hyperimmune sera participated in homologous and cross-cytolysis of alphavirus-infected cells, and the use of monospecific antisera to sin structural proteins suggested that e1 and e2 could serve as target proteins in cytolysis. proteins from purified virions or infected cells were extracted with nonidet p-40, denature ...19846694261
release of fatty acids from virus glycoproteins by hydroxylamine.the fatty acids bound to the glycoproteins of sindbis and vesicular stomatitis viruses can be released by treating the protein with 1 m hydroxylamine at ph 8.0, but the rates of release vary greatly among the three proteins. the most labile fatty acyl bonds were in the sindbis virus pe2/e2 proteins and the most stable were in the e1 protein. some of the fatty acids in sindbis virus glycoproteins were reduced to the alcohol after treatment with sodium borohydride, indicating that protein-bound fa ...19846324873
[inhibiting effect of colcemid on the development of cytopathic changes due to the sindbis virus].the model of chinese hamster (cricetulus griseus) cell line infected with sindbus virus was used to show that the presence in the maintenance medium of 0.01-0.1 micrograms/ml of colcemide inhibited the development of cytopathic changes, accumulation of viral antigens, and virus-specific complement-dependent cytolysis without affecting infectious virus production. the addition to the medium of 0.5% immune serum to sindbis virus resulted not only in a similar inhibition but in a decrease of infect ...19846328766
[effect of an alphavirus infection in pregnant mice on the susceptibility of their progeny to homologous infection in the postnatal period].infection of random-bred mice with sindbis virus at various intervals of pregnancy results in increased resistance of their offsprings to infection with this virus in the first days after birth. antibodies present in the colostrum and milk of immunized females play an important role in decreasing the susceptibility of sucklings to alphavirus infection.19846328767
the role of mast cells in virus-induced inflammation in the murine central nervous system.the mononuclear inflammatory response to sindbis virus infection of the central nervous system is analogous to the cutaneous delayed-type hypersensitivity reaction. it is dependent on sensitized t cells for initiation, but many of the cells present are nonsensitized bone marrow-derived cells. tissue mast cells have been shown to be important for the development of the delayed-type hypersensitivity reaction in the skin where capillary endothelial cells are joined by tight junctions. to determine ...19846329524
establishment and analysis of a system which allows assembly and disassembly of alphavirus core-like particles under physiological conditions in vitro.core-like (cl) particles which closely resemble alphavirus cores in size, shape, and relative amount of nucleic acid and protein have been assembled in vitro from sindbis (sin) virus core (c) protein and single-stranded nucleic acids in buffer containing 1 m urea [g. wengler, u. boege, g. wengler, h. bischoff, and k. wahn (1982) virology 118, 401-410]. we have now analyzed the interaction of sin virus c protein and nucleic acids in vitro under conditions designed to resemble those present in the ...19846702103
host-dependent mutants of sindbis virus whose growth is restricted in cultured aedes albopictus cells produce normal yields of virus in intact mosquitoes.two host-dependent (hd), temperature-sensitive (ts) mutants of sindbis virus (sv), clones 35 and 58, which are restricted in their ability to grow at 34 degrees in cultured aedes albopictus cells [k.j. kowal and v. stollar (1981). virology 114, 140-148] were not restricted in their ability to grow at 28-34 degrees after intrathoracic inoculation of ae. albopictus, ae. dorsalis, ae. epactius, anopheles freeborni, and culex tarsalis mosquitoes. compared to standard sv (svstd), the growth of sv clo ...19846710871
immunocytochemical identification and quantitation of the mononuclear cells in the cerebrospinal fluid, meninges, and brain during acute viral meningoencephalitis.the mononuclear cells of the central nervous system (cns) inflammatory response were characterized in cerebrospinal fluid (csf), meningeal exudate, and brain parenchyma of mice 3-14 d after infection with sindbis virus. the inflammatory infiltrate in csf peaked and resolved before that of the parenchyma or meningeal exudate. immunoperoxidase staining with monoclonal antibodies identified csf inflammatory cells to be almost exclusively t cells, while inflammatory cells in the brain parenchymal pe ...19846363596
a simplified microwell pseudoreplica for the detection of viruses by electron microscopy and immunoelectron microscopy.simplified procedures for immunoelectron microscopy (iem) and electron microscopy (em) are described. the procedures employ the principle of agar filtration and pseudoreplication. the modification consisted of the use of microwells for storage of gels with or without antiserum (for iem or em, respectively) and an array of containers in which pseudoreplication and negative staining were performed. the containers were prepared from 5 ml syringes from which the needle holding parts were cut. this d ...19846394602
effects of lysosomotropic weak bases on infection of bhk-21 cells by sindbis virus.the effects of the lysosomotropic weak bases chloroquine, ammonium chloride, and amantadine as well as dansylcadaverine (an inhibitor of receptor mediated endocytosis) on the replication of sindbis virus in tissue-cultured cells was examined. chloroquine had no effect on the expression of virus-induced homologous interference. none of these drugs significantly affected the ability of a complex of a cell and single virion to form an infectious center. chloroquine and ammonium chloride were found ...19846492263
evidence that ribavirin is transported in aedes albopictus cells by the nucleoside transport system.aedes albopictus cells (cae-3-6) deficient in the transport of nucleosides showed a markedly impaired ability to transport the antiviral compound, ribavirin. furthermore, in order to inhibit either cell growth or viral replication, the transport negative cae-3-6 cells required significantly higher concentrations of ribavirin than were needed for a similar degree of inhibition in the parental c7 cells. although ribavirin did lower the level of gtp in cae-3-6 cells the effect was slower and less s ...19846532319
properties of defective interfering particles of sindbis virus generated in vertebrate and mosquito cells.defective interfering (di) particles of sindbis virus were generated during serial, undiluted passage of a cloned virus stock in both chick embryo fibroblast (cef) cells and aedes albopictus mosquito cells. di particle-containing stocks were identified by their ability to interfere with standard virus replication and to synthesize small di rna species in the cell type in which they were generated. di rna species generated during serial passage in cef cells were able to replicate in both vertebra ...19846693857
common and distinct regions of defective-interfering rnas of sindbis virus.defective-interfering (di) particles are helper-dependent deletion mutants which interfere specifically with the replication of the homologous standard virus. serial passaging of alphaviruses in cultured cells leads to the accumulation of di particles whose genomic rnas are heterogeneous in size and sequence composition. in an effort to examine the sequence organization of an individual di rna species generated from sindbis virus, we isolated and sequenced a representative cdna clone derived fro ...19846699940
regulation of asparagine-linked oligosaccharide processing. oligosaccharide processing in aedes albopictus mosquito cells.we have examined the synthesis and processing of asparagine-linked oligosaccharides from aedes albopictus c6/36 mosquito cells. these cells synthesized a glucose-containing lipid-linked oligosaccharide with properties identical to that of glc3man9glcnac2-pp-dolichol. results of brief pulse label experiments with [3h]mannose were consistent with the transfer of glc3man9glcnac2 to protein followed by the rapid removal of glucose residues. pulse-chase experiments established that further processing ...19846698972
role of signal recognition particle in the membrane assembly of sindbis viral glycoproteins.we have investigated the role of signal recognition particle (srp) in the biosynthesis of sindbis glycoproteins by translating the viral 26s mrna in a wheat-germ cell-free system. srp was shown to have no effect on the synthesis or proteolytic processing of the cytoplasmic c protein. in contrast, the membrane integration and the proteolytic processing of the viral glycoproteins pe2 and e1 were demonstrated to be srp-dependent. in the absence of microsomal membranes, srp caused an arrest of the s ...19846723645
synergism of antiviral activity in cell cultures treated with low concentrations of interferon and interferon-treated lymphocytes.human t cells treated with low levels of interferon (ifn) (1-10 units/ml), and washed to remove the ifn, transferred the same level of antiviral activity to recipient wish cells as an equivalent ifn treatment alone could induce in wish cells. further, when t cells pretreated with ifn (1-10 units/ml) were cocultivated with wish cells in the presence of ifn (1-10 units/ml), a 2.5- to 5-fold greater level of protection developed than could be expected from the additive effect of each. antibody to l ...19846333028
antibody against viruses in maternal and cord sera: non-specific inhibitors are found to higher titre on the maternal side of the circulation.pregnancies were identified in which maternal igg antibodies against rubella virus were not detectable by single radial haemolysis. twenty paired maternal/cord sera were then tested for haemagglutination-inhibiting (hi) activity against rubella virus without kaolin pretreatment of the sera. in the absence of specific antibody, the hi activity observed could thus be ascribed to the effect of non-specific inhibitors. the hi activity in maternal sera was significantly (p less than 0.001) higher tha ...19846736640
a mutant of sindbis virus with a host-dependent defect in maturation associated with hyperglycosylation of e2.following serial passage of sindbis virus (sv) on aedes albopictus mosquito cells a mutant (svap15/21) was isolated which in chick cells produced small plaques and was temperature sensitive (ts). at 34.5 degrees this mutant replicated normally in mosquito cells, but only poorly in chick or bhk cells. in the vertebrate cells svap15/21 was rna+ at both 34.5 and 40 degrees and on the basis of complementation tests carried out at 40 degrees, was assigned to complementation group e. the block in the ...19846740942
on the role of oligosaccharide trimming in the maturation of sindbis and influenza virus.the alpha-glucosidase inhibitor bromoconduritol inhibits the formation of the n-linked, complex-type oligosaccharides of the glycoproteins from influenza viruses (fowl plague virus, influenza virus pr-8) and from sindbis virus. viral glycoproteins produced in bromoconduritol-treated chicken-embryo and baby-hamster kidney cells are fully glycosylated, but accumulate n-linked, high-mannose oligosaccharides of the composition glc1manx (glcnac)2 (x = 7, 8, and 9). other alpha-glucosidase inhibitors ...19846743024
alterations in monovalent cation transport in sindbis virus-infected chick cells.influx experiments using the potassium tracer 86rb+ indicated that the activity of the na+k+ atpase, or sodium pump, was reduced 40-50% as a consequence of sindbis virus infection of avian fibroblasts. the inhibition of this ouabain-sensitive, active transport system temporally correlated with a decrease in the intracellular k+ concentration and the termination of cellular protein synthesis. by contrast, the rate of influx facilitated by the furosemide-sensitive (na+k+cl-) cotransport system was ...19846320528
poliovirus infection of cyclophosphamide-treated mice results in persistence and late paralysis: i. clinical, pathologic, and immunologic studies.an attenuated human poliovirus infection of cyclophosphamide (cy)-treated mice was developed as a model of persistent cns enterovirus infections and as an investigation of the interaction of virus with motor neurons during persistence. ten percent of mice inoculated intracerebrally with undiluted virus developed clinical disease by day 90, but of those treated with cy, 80% developed disease. at higher virus dilutions plus cy there was a marked increase in the incubation period. the latest onset ...19846322051
complete nucleotide sequence of the genomic rna of sindbis virus.the entire nucleotide sequence of the genomic rna of the type virus of the alphavirus genus, sindbis virus, has been determined. the genome is 11,703 nucleotides in length, exclusive of the 5' cap and the 3'-terminal poly(a) tract. after the 5'-terminal cap there are 59 nucleotides of 5' nontranslated nucleic acid followed by a reading frame of 7539 nucleotides that encodes the nonstructural polypeptides and which is open except for a single opal termination codon. following 48 untranslated base ...19846322438
properties of sindbis virus variants from infected culex tarsalis mosquitoes.plaque-purified sindbis virus was passed three times in culex tarsalis mosquitoes and progeny viruses were isolated by plaque purification on a cloned line of aedes albopictus cells. nine of ten clones examined differed from wild-type (wt) virus with respect to their plaque morphology characteristics in chick embryo fibroblast (cef) and/or a. albopictus cells. seven clones were temperature-sensitive and failed to replicate or synthesize viral rna in cef cells at 41 degrees c. at 35 degrees c in ...19846726183
studies on simian hemorrhagic fever virus nucleocapsids.purified simian hemorrhagic fever (shf) virions are shown to have a sedimentation coefficient of 214s when compared with previously determined figures for sindbis virus cosedimented in neutral sucrose gradients. the nucleic acid content in shf virions was about 8 per cent of the total virionic mass. nucleocapsids obtained by treating shf virions with nonionic detergent and analyzed by ultracentrifugation in neutral sucrose gradients gave rnase sensitive- but dnase resistent particles with a repr ...19846541899
variation in homotypic and heterotypic interference by defective interfering viruses derived from different strains of semliki forest virus and from sindbis virus.there was strong interference between various virulent and avirulent strains of semliki forest virus (sfv) and their respective defective interfering (di) viruses but in other combinations interference was variable: it could be equally strong, weak or could not be demonstrated. on passage, this spectrum of interfering activity changed, some combinations showing greater interference than before and others less. heterotypic interference between di sfv, di sindbis virus and standard viruses was cle ...19846726189
expression of sindbis virus structural proteins via recombinant vaccinia virus: synthesis, processing, and incorporation into mature sindbis virions.we have obtained a vaccinia virus recombinant which contains a complete cdna copy of the 26s rna of sindbis virus within the thymidine kinase gene of the vaccinia virus genome. this recombinant constitutively transcribed the sindbis sequences throughout the infectious cycle, reflecting the dual early-late vaccinia promoter used in this construction. the sindbis-derived transcripts were translationally active, giving rise to both precursor and mature structural proteins of sindbis virus, includin ...19854032536
alphavirus neurovirulence: monoclonal antibodies discriminating wild-type from neuroadapted sindbis virus.wild-type sindbis virus strain ar339 (sv) and a neurovirulent mutant (nsv), derived by neonatal and weanling mouse brain passage, both cause acute fatal encephalitis in neonatal mice, but nsv alone kills adult mice. nsv cannot be distinguished from sv by immune sera or simple biochemical tests. to localize the molecular changes associated with neuroadaptation, we used a new array of 30 anti-sv monoclonal antibodies to probe for differences between sv and nsv in four tests: immunoprecipitation, e ...19852411947
the calcium ionophore a23187 evokes and potentiates antiviral activity of interferon.calcium ionophore a23187, which causes a rapid efflux of ca2+ from cells, evokes an antiviral response in mouse lb, simian cos-1, hela, human amniotic (u), baby hamster kidney (bhk), and vero cells against sindbis (sbv) and vesicular stomatitis (vsv) viruses. the degree of antiviral activity depends on the type of cell, virus, and the dose of a23187. a23187 inhibits the production of infectious vsv; however, vsv particle production was not significantly inhibited as measured by viral rna and vir ...19852418129
interferon induction by viruses. xiv. development of interferon inducibility and its inhibition in chick embryo cells "aged" in vitro.studies with a number of viruses revealed a time-dependent acquisition of interferon (ifn) inducibility in primary chick embryo cells as they "aged" in vitro for 2-12 days at a confluent cell density without a medium change. the time-course for the development of ifn inducibility was established by generating and analyzing a family of dose (multiplicity)-response (ifn yield) curves, using newcastle disease virus (ndv, strain lasota) as the inducer. cells produced little or no ifn for the first 4 ...19852418133
the nonstructural proteins of sindbis virus as studied with an antibody specific for the c terminus of the nonstructural readthrough polyprotein.a dodecapeptide containing the sequence of the c terminus of the nonstructural polyprotein of sindbis virus has been synthesized and used to immunize rabbits. the antisera obtained precipitated polypeptides from cells infected with the hr strains of sindbis or with temperature-sensitive mutants ts11 or ts18. four different polypeptides, having apparent molecular weights of approximately 250,000, 220,000, 155,000, and 72,000, were immunoprecipitated by the antipeptide antiserum. the largest of th ...19854082500
sindbis virus mutants able to replicate in methionine-deprived aedes albopictus cells.previous work from this laboratory has shown that the replication of sindbis virus (sv) in aedes albopictus cells is sensitive to methionine withdrawal. this sensitivity is thought to reflect a diminished concentration of s-adenosylmethionine (ado met) resulting from methionine starvation. serial passage of sv on ae. albopictus cells maintained in low concentrations of methionine gave rise to a population of mutants whose replication in mosquito cells was resistant to methionine starvation. in v ...19854060595
expression of recombinant vaccinia virus-derived alphavirus proteins in mosquito cells.a recombinant vaccinia virus strain which contains and expresses a 26s cdna insert encoding sindbis virus structural proteins (vv:3s) was used to infect a continuous line of aedes albopictus mosquito cells. there were not visible cytopathic effects due to the virus infection and the cells continued to grow normally. however, examination of the proteins present in the cytoplasm of the infected cells with sindbis virus-specific antisera revealed that sindbis virus proteins were being synthesized a ...19854067584
use of chicken and rabbit antibodies in a solid phase protein a radioimmunossay for virus detection.a new rapid indirect solid phase radioimmunoassay was developed for the detection of sindbis virus. chicken antibodies were adsorbed onto wells in microplates to serve as 'capture antibodies' and rabbit antibodies were used as the second antibody. 125i-labelled protein a that does not bind to chicken antibodies, but binds firmly to rabbit antibodies was used as the tracer. all the steps necessary for the development of the assay are described. the minimal amount of sindbis virus detectable was a ...19854077951
immunocytochemical study of the partition and distribution of sindbis virus glycoproteins in freeze-fractured membranes of infected baby hamster kidney cells.sindbis virus-infected baby hamster kidney cells were analyzed by thin section fracture-label. specific immunolabel with antiviral glycoprotein antibodies or with conventional lectin label (wheat germ agglutinin) were used in conjunction with colloidal gold-conjugated protein a or ovomucoid, respectively. in addition, intact infected cells were analyzed with both labeling procedures. experiments with sindbis infected-chick embryo fibroblast cells were carried out as controls. viral transmembrane ...19854044639
pattern of glycosylation of sindbis virus envelope proteins synthesized in hamster and chicken cells.the tryptic glycopeptides of the sindbis virus envelope glycoproteins e1 and e2 grown in bhk and chick cells were purified by gel filtration followed by high-pressure liquid chromatography. each of the purified glycopeptides was analyzed by n-terminal sequencing to identify from which of the potential glycosylation sites it was derived. the type of oligosaccharide chain attached to each glycopeptide was determined from gel filtration analysis of the pronase-digested glycopeptides, and the relati ...19854060569
functional analysis of the a complementation group mutants of sindbis hr virus.the 10 members of the a complementation group of temperature-sensitive (ts) mutants of sin hr, the heat-resistant strain of sindbis virus, were divided into two phenotypic subgroups. subgroup i mutants (ts15, ts17, ts21, ts24, and ts133) demonstrated temperature-sensitive 26 s mrna synthesis, whereas subgroup ii mutants (ts4, ts14, ts16, ts19, and ts138) did not; both ts4 and ts19 demonstrated defective 26 s mrna synthesis at 30 degrees. none of the a group mutants demonstrated temperature-sensi ...19854060589
in vitro synthesis of the gene coding for the glycoprotein e1 of sindbis virus.ds cdna of the 42s virionic rna of sindbis virus has been synthesized and cloned in the plasmid pbr 322. restriction map analysis and hybridization studies show that two clones cover the 3' end non coding region of the rna, the whole membrane glycoprotein e1 and a peptide of mw 6,000 daltons. the use of these clones in experiments of gene expression in mammalian cell is discussed.19854010526
detection of immunologically cross-reacting capsid protein of alphaviruses on the surfaces of infected l929 cells.hyperimmune, but not normal immune, monospecific antiserum made to capsid protein of sindbis virus (sin) was found to cause cytolysis equally well of both sin- and semliki forest virus-infected l929 cells in antibody-dependent, complement-mediated cytotoxicity assays. the cell surface reactivity of the hyperimmune antiserum was also demonstrated by solid-phase radioimmune assays with unfixed infected cells or infected cells fixed with low concentrations of glutaraldehyde (0.025%) before reactivi ...19853965743
mrna activity of a sindbis virus defective-interfering rna.we obtained sindbis defective-interfering particles by nine and undiluted passages of standard virus on chicken embryo fibroblasts. these particles contain a deleted 20s rna molecule which has mrna activity, as shown by translation in cell-free systems in vitro. in infected cells, this mrna activity appeared to be totally inhibited except at very late times postinfection.19854020971
rdb--a new product of plant origin for cell culture dispersion.rdb is a crude preparation extracted from a plant source. it is a very potent agent for dispersion of monolayer cell cultures as well as for the preparation of primary cell suspensions. it was found to be most effective in dispersing a wide range of animal and mosquito cells and dissociating neuronal and muscular tissue for primary cell cultures. rdb was also found to be useful for preparation of primary culture for chick embryo fibroblasts. after treatment with rdb cell viability was found to b ...19854043538
genetic and antigenic variations among geographical isolates of sindbis virus.the genetic and antigenic variation in 12 sindbis (sin) virus isolates from four zoogeographic regions (paleoarctic, ethiopian, oriental and australian) has been examined at a molecular level. rnase t1 oligonucleotide fingerprinting of genomic rna from sin isolates revealed that the primary structure of the rna from viruses from each zoogeographic region was unique. the e1 and e2 glycoproteins and the capsid protein of two isolates from each zoogeographic region were compared by tryptic peptide ...19853981136
bhk cells expressing sindbis virus-induced homologous interference allow the translation of nonstructural genes of superinfecting virus.the process by which sindbis virus excludes superinfecting homologous virus was investigated with the use of temperature-sensitive mutants. mutants in two rna-negative complementation groups were found to be defective in their ability to establish interference at the nonpermissive temperature. these mutants were unable to establish interference in a mixed infection (complementation), suggesting that both were defective in a common gene product. homologous interference was found to block the repl ...19853989908
the ratio of plasma membrane cholesterol to phospholipid and the inhibition of sindbis virus maturation by low nacl medium.sindbis virus maturation is inhibited by low nacl medium in chick embryo cells and in one strain of bhk cells, but not in another strain of bhk cells which has a different passage history. the plasma membrane of the cells in which sindbis virus maturation is resistant to low nacl medium has a higher ratio of cholesterol to phospholipid than the other cells. cholesterol-containing liposomes, but not cholesterol-free liposomes, can release sindbis virus from low nacl-inhibited cells. these results ...19853998710
persistent infection of rabies virus (hep-flury strain) in human neuroblastoma cells capable of producing interferon.apparent interferon-mediated persistent infection of rabies virus (hep-flury strain) was established in a human neuroblastoma sym-i (clone k-104) cell line, which had the ability to produce interferon. this infection produced variable but small amounts of progeny virus and interferon (up to 100 iu/ml), and resisted superinfection with vesicular stomatitis virus (vsv) and sindbis virus as well as homologous rabies virus. the treatment of this infection with anti-interferon antibody stimulated vir ...19853998711
sindbis virus glycoproteins are abnormally glycosylated in chinese hamster ovary cells deprived of glucose.we have previously demonstrated that sindbis virus infection of chinese hamster ovary (cho) cells altered the protein glycosylation machinery of the cell, so that both normal, full-size (nine mannose-containing) oligosaccharides and abnormal, "truncated' (five mannose-containing) oligosaccharides are transferred from lipid-linked precursors to newly synthesized viral membrane glycoproteins. in the present studies, we have examined the precursor oligosaccharides on viral glycoproteins that were p ...19854020347
the effects of inhibitors of glucosidase i on the formation of sindbis virus.we have examined the effects of deoxynojirimycin and castanospermine, compounds known to inhibit the removal of glucose from high mannose asparagine-linked oligosaccharides, on the formation of sindbis virus. these drugs inhibited virion formation in baby hamster kidney (bhk) cells, 15b - the cho cell line that lacks glcnac transferase activity, and chicken embryo fibroblasts, although our results with the latter cells were variable. we analyzed the [3h]mannose-labeled oligosaccharides from sind ...19853158136
sindbis virus proteins nsp1 and nsp2 contain homology to nonstructural proteins from several rna plant viruses.although the genetic organization of tobacco mosaic virus (tmv) differs considerably from that of the tripartite viruses (alfalfa mosaic virus [almv] and brome mosaic virus [bmv]), all of these rna plant viruses share three domains of homology among their nonstructural proteins. one such domain, common to the almv and bmv 2a proteins and the readthrough portion of tmv p183, is also homologous to the readthrough protein nsp4 of sindbis virus (haseloff et al., proc. natl. acad. sci. u.s.a. 81:4358 ...19853968720
inactivation of viruses in labile blood derivatives. ii. physical methods.the thermal inactivation of viruses in labile blood derivatives was evaluated by addition of marker viruses (vsv, sindbis, sendai, emc) to anti-hemophilic factor (ahf) concentrates. the rate of virus inactivation at 60 degrees c was decreased by at least 100- to 700-fold by inclusion of 2.75 m glycine and 50 percent sucrose, or 3.0 m potassium citrate, additives which contribute to retention of protein biologic activity. nonetheless, at least 10(4) infectious units of each virus was inactivated ...19853934802
immunisation of cattle with a recombinant togavirus-vaccinia virus strain.genetic engineering techniques have been used to construct a vaccinia virus recombinant which contains and expresses togavirus (sindbis) genetic information. intradermal inoculation of this recombinant strain into calves caused a transient pock-type lesion at the site of inoculation and elicited the production of substantial levels of anti-sindbis virus neutralising antibodies. these results suggest that recombinant vaccinia virus vaccines may have potential for use in veterinary medicine.19853862196
cross-reactive target antigen in cell-mediated cytolysis of cells infected with a temperature-sensitive mutant of sindbis virus.cytotoxic t lymphocytes (ctl) against alphavirus-infected l929 cells were generated in mice by two in vivo immunizations of one virus or by in vivo immunization followed by in vitro stimulation of splenocytes with infected peritoneal exudate cells or splenocytes. these ctl caused specific h-2-restricted cytolysis equally well with homologous, heterologous or sindbis virus ts20 mutant-infected cells. thus, specific ctl appear to be cross-reactive components in normal immunity to alphaviruses and ...19853873514
sequence analysis of three sindbis virus mutants temperature-sensitive in the capsid protein autoprotease.we have cloned and sequenced the cdna made to the region of rna encoding the structural proteins of three complementation group c mutants of sindbis virus, ts2, ts5, and ts13, and of their revertants. these mutants possess defects in the posttranslational processing of their structural proteins at the nonpermissive temperature. comparison of the deduced amino acid sequences of the mutants with those of the revertants and with the parental hr strain of virus showed all three mutants to have singl ...19853895223
sensitive enzyme immunoassay for detecting immunoglobulin m antibodies to sindbis virus and further evidence that pogosta disease is caused by a western equine encephalitis complex virus.an antibody capture enzyme immunoassay (eia) was adapted for the detection of immunoglobulin m (igm) antibody to sindbis (sin) virus. sera from humans with a febrile illness characterized by rash and arthralgia in eastern finland (pogosta [pog] disease) and sweden (ockelbo disease) and from humans with western equine encephalitis (wee) virus infection in the united states were tested for igm antibodies by eia. seroconversions were documented in patients with pog disease and with wee virus infect ...19853908469
[single radial hemolysis of arboviruses]. 19853914374
characteristics of antiviral and anticellular activities of human recombinant interferon-gamma.the antiviral and anticellular activities of recombinant human interferon-gamma (re-ifn-gamma) were compared with those of natural human interferon-gamma (ifn-gamma), natural human interferon-alpha (ifn-alpha), and recombinant human interferon-beta (reifn-beta). reifn-gamma and ifn-gamma induced the antiviral state in fl cells against sindbis virus more rapidly than ifn-alpha or reifn-beta. the antiviral state induced by a short exposure time to ifn-gamma declined rapidly after the removal of if ...19853922841
studies of defective interfering rnas of sindbis virus with and without trnaasp sequences at their 5' termini.three of six independently derived defective interfering (di) particles of sindbis virus generated by high-multiplicity passaging in cultured cells have trnaasp sequences at the 5' terminus of their rnas (monroe and schlesinger, j. virol. 49:865-872, 1984). in the present work, we found that the 5'-terminal sequences of the three trnaasp-negative di rnas were all derived from viral genomic rna. one di rna sample had the same 5'-terminal sequence as the standard genome. the di rnas from another d ...19853973983
[assays of cytotoxicity and antiviral activity of crude and semipurified extracts of green leaves of melia azedarach l].crude extracts from fresh green leaves of melia azedarach l contain an antiviral factor (fav) able to inhibit the replication of several animal viruses, e.g. polio, vsv, hsv, fmdv, sindbis, junín, pichinde and tacaribe in vero or bhk-21 cells. crude preparations were subjected to different steps of purification like chromatography on sephadex g-100 and deae-sephadex. the antiviral activity of g-100 and deae fractions was fully conserved, whereas contaminating proteins were lost. two types of cyt ...19852825236
inhibition by norakin (triperiden) of sindbis virus infection in mice.intranasal (i. n.) infection with 10 ld50 of sindbis virus caused acute encephalomyelitis and death in abd2f1 mice 3-7 days post infection (p.i.). histologic lesions were found in the cns, pancreas. liver, parotid glands, exorbital lacrimal glands, lymphoid organs and kidneys. repeated oral administration of the anticholinergic anti-parkinson drug norakin protected infected animals from death in a dose-dependent manner when treatment was started prior to but not after virus inoculation. the maxi ...19852864821
failure of high doses of potentially antiviral agents to prevent death in virus-infected mice.the influence of increasing doses of various potentially antiviral agents on mengo virus-and sindbis virus-infected mice was assessed determining death rates and histologic lesions. all drugs given in abundance showed dose-dependent decrease of antiviral activity following the maximum protective effects in either animal model. from the toxicological point of view the antiviral agents in question could be classified into two groups. high doses of tilorone hydrochloride or 10-carboxymethyl-9-acrid ...19852864822
culex theileri and sindbis virus; salivary glands infection in relation to transmission. 19852852707
sindbis virus isolations from saudi arabian mosquitoes.a study in late 1979 to early 1980 was conducted to assess arbovirus activity in the eastern province of saudi arabia. from 38,245 mosquitoes collected at 3 locations, 16 isolations of sindbis virus were made: 13 from culex univittatus and one each from cx tritaeniorhynchus, cx pipiens complex, and culex spp. these isolations represent the first records of a mosquito-borne virus from the gulf of arabia and implicate cx univittatus as the principal vector. a potential risk of human diseases exist ...19852859676
differential expression of surface proteins, virus receptors and histocompatibility antigens in sv40-transformed human choroid cells and their clones.human choroid (hc) cells transformed by simian virus 40 (hc/sv40) and some of their soft agar-derived clones were utilized to study the influence of sv40 transformation on the expression of some differentiation parameters. the presence of receptors for dna and rna viruses, known to induce cytopathic effects in target cells, always occurred in normal hf and hc/sv40 cells as well as in their derived clones, whereas differences were observed in the expression of influenza a and sindbis virus recept ...19852983079
hazelhurst-vesicular-stomatitis-virus g and sindbis-virus e1 glycoproteins undergo similar host-cell-dependent variation in oligosaccharide processing.we have examined and compared the host-cell-dependent glycosylation of the g glycoprotein of vesicular-stomatitis virus (hazelhurst strain) and the e1 and e2 glycoproteins of sindbis virus replicated by baby-hamster kidney, chicken-embryo fibroblast and mouse l929 monolayer cell cultures. the results of endo-beta-n-acetylglucosaminidase h digestion of viral proteins labelled with [3h]mannose or leucine and pronase-digested glycopeptides labelled with [3h]mannose indicated that both the g protein ...19852994631
[isolation of the causative agent of karelian fever from aedes sp. mosquitoes].the results of isolation of an alphavirus strain from aedes sp. mosquitoes collected in the focus of karelian fever are presented. according to the results of serological studies, the isolated strain leiv-9298 karelia belongs to the antigenic complex sindbis-western equine encephalomyelitis. the appurtenance of the isolated agent to the alphavirus genus has been confirmed by electron microscopic examinations. a rise of antibody titres to leiv-9298 karelia virus in paired sera of subjects with a ...19852996238
antiviral effect of 1-morpholinomethyl-tetrahydro-2(1h)-pyrimidinone (dd-13) in experimental alphaviral infections in white mice.1-morpholinomethyl-tetrahydro-2(1h)-pyrimidinone (dd-13), a selective inhibitor of the alphaviral reproduction in vitro, manifests a pronounced antiviral activity in experimental infections with semliki forest virus (sfv) and sindbis virus in white mice (intraperitoneally inoculated with 10-10 000 ld50). introduced subcutaneously in mice infected with sfv the compound was effective within the dose range of 4.7-300 mg/kg. the effective dose (ed)50 value of dd-13 is about 18.7 mg/kg and the maximu ...19853000394
differential effects of photoactive furanyl compounds on virus functions. 19853003768
[blocking of sindbis virus replication in the body of infected mice using an inhibitor of chymotrypsin-like proteases].parenteral administration of an inhibitor of chymotrypsin-like proteases (tpck) to mice infected with alphavirus (sindbis ar/339 strain) blocked virus replication in the brain and inhibited the development of viremia in the infected animals. the most likely mechanism of tpck antiviral effect seems to consist in disturbance of proteolytic processing of viral proteins.19852998094
susceptibility of different leukemic cell lines to the anticellular and antiviral effects of interferons.a total of 18 different types of human leukemic cell lines were tested for their susceptibility to the anticellular and antiviral effects of interferons (ifns) alpha, beta and gamma. in general, only the three myelogenous leukemic cell lines u937, kg-1 and hl-60 were found to be highly susceptible to the anticellular effect of the different ifns while cells of the other lineages were relatively resistant. in order to determine whether the cell lines were sensitive to the antiviral effects of ifn ...19852999858
[ultrastructural changes of neonatal thymuses of mice infected with virus]. 19853004756
[studies on the combined treatment with cyclophosphamide and virus in mice transplanted with s180 ascitic tumor cells]. 19852938760
[preliminary studies on the efficacy of treating twice with different virus strains for s180 ascitic mice]. 19852939992
morphological and functional polarity of an epithelial thyroid cell line.the thyroid epithelial cell line frt in monolayer culture appeared to be strongly polarized by morphological criteria. cells were connected by tight junctions, exposed microvilli toward the culture medium and formed domes at confluency. frt cells were infected with vesicular stomatitis virus (vsv) and sindbis virus and the budding polarity was examined 8 and 16 h after infection, respectively. vsv budding occurred preferentially from the basolateral domain of plasma membrane, while sindbis virus ...19852992984
effect of tunicamycin on the development of the cytopathic effect in sindbis virus-infected avian fibroblasts.in sindbis virus-infected avian cells the development of the cytopathic effect is correlated with the disruption of plasma membrane function. sindbis virus inhibits the activity of the na+k+atpase, a membrane-associated enzyme complex which regulates intracellular monovalent cation levels. tunicamycin, which blocks envelope protein glycosylation, prevents inhibition of na+k+atpase activity and the development of morphological changes in sindbis virus-infected cells. although inhibition of na+k+a ...19852998024
expression of genes encoding vesicular stomatitis and sindbis virus glycoproteins in yeast leads to formation of disulfide-linked oligomers.saccharomyces cerevisiae strains transformed with plasmids containing cdnas coding for the glycoproteins of vesicular stomatitis or sindbis viruses can be induced to produce large amounts of glycosylated virus glycoproteins. studies reported here show that these proteins from high molecular weight disulfide-linked oligomers in the yeast endoplasmic reticulum. oligomers were also found for two genetically altered forms of vsv g; one of these was lacking the membrane anchor domain and the other ha ...19863016985
synergistic anticellular and antiviral activities of human recombinant interferon-gamma and -beta.the synergism of anticellular and antiviral activities of recombinant human interferon-gamma (reifn-gamma) and recombinant human interferon-beta (reifn-beta) was examined in vitro using human melanoma sk-mel-28 cells. some differences were detected in the kinetics of anticellular activity between both ifns, namely the inhibitory effect of reifn-beta occurred earlier than that of reifn-gamma. significant synergism was detected in the anticellular activity of both ifns when growth curves and isobo ...19863031263
[medical topics: ockelbo disease/myoglobin and myocardial infarction]. 19863039231
different kinetics of antiviral and anticellular activities between human recombinant and natural interferon-gamma arising from different receptor-binding properties.human recombinant interferon-gamma (reifn-gamma) and human natural interferon-gamma (ifn-gamma) showed significant differences in antiviral and anticellular activities. namely, reifn-gamma exhibited antiviral activity against sindbis virus and anticellular activity against hela s3 cells at significantly lower concentrations as compared with ifn-gamma at short exposure times of between 1 and 4 hr. this difference of activities was explicable in terms of different binding activities of the two ifn ...19863095289
elevated serum immune complex levels in pogosta disease, an acute alphavirus infection with rash and arthritis.circulating immune complexes (cic) were studied in pogosta disease, an acute alphavirus infection with fever, rash and arthritis. the disease is caused by a virus antigenically closely related to sindbis virus. 75 serum specimens from 25 patients with serologically verified infection were obtained from 1-87 days after the onset. six different cic detection methods were used and cics were observed in all patients at least with one test. tests based on cic binding onto human platelets followed the ...19863029375
sindbis virus mutant ts20 of complementation group e contains a lesion in glycoprotein e2.a technique has been devised to readily obtain the entire structural protein region of sindbis virus cloned into a plasmid vector. this method uses the fact that the nearest site for restriction enzyme hindiii to the 3' terminal poly(a) occurs at nucleotides 6266-6271 in the genomic rna. inserts extending from the poly(a) tract to this hindiii site are 5438 nucleotides long (excluding the poly a tract) and contain the entire 4106-nucleotide structural protein region. using an oligo(dt)-tailed ve ...19863008426
regulated expression of sindbis and vesicular stomatitis virus glycoproteins in saccharomyces cerevisiae.cdnas encoding either the structural proteins (capsid and glycoproteins e1 and e2) of sindbis virus or the glycoprotein of vesicular stomatitis virus (vsv) were fused to the saccharomyces cerevisiae galactokinase gene (gal1) promoter and inserted into a yeast shuttle vector. after addition of galactose to yeast transformed with this vector, 2.5-3% of total yeast protein synthesis was detected as virus proteins by specific anti-virus protein antibodies. in cells containing the sindbis virus struc ...19863012523
scanning fluorescence correlation spectroscopy. ii. application to virus glycoprotein aggregation.scanning fluorescence correlation spectroscopy is a new approach to measuring changes in the state of aggregation of cell membrane proteins. measurements of the mean number of aggregates of virus glycoproteins from sindbis virus and vesicular stomatitis virus agree with the findings of a recent fluorescence photobleaching recovery study on the same systems (johnson, d.c., m.j. schlesinger, and e.l. elson, 1981, cell, 23:423-431). sindbis virus glycoproteins are immobilized and cannot be induced ...19863013328
sindbis and west nile virus infections in the witwatersrand-pretoria region.from mid-december 1983 until mid-april 1984, there was an epidemic of sindbis (sin) virus infection in the witwatersrand-pretoria region in which hundreds of human cases were diagnosed clinically. twenty-eight of these diagnoses were confirmed in the laboratory by seroconversion as being infections with sin virus, and 5 cases of infection with west nile (wn) virus were also found. attempts to isolate virus from 66 patients, mainly from serum specimens, were unsuccessful. infection rates for the ...19863016922
experimental assessment of the vector competence of culex (culex) neavei theobald with west nile and sindbis viruses in south africa.culex univittatus is the maintenance vector of west nile (wn) and sindbis (sin) viruses on the inland plateau of south africa and also transfers infection to man. both viruses have frequently been isolated from this mosquito and human immunity is high on the plateau. in the natal lowlands where cx univittatus is replaced by cx neavei, apparently the main vector there, immune rates are low and few isolations have been made from this species. vector competence experiments were carried out with cx ...19863024364
sindbis virus infection increases hexose transport in quiescent cells.sindbis virus infection of baby hamster kidney cells or chick embryo cells resulted in a significant increase in the rate of uptake of [2-3h]deoxy-d-glucose ([3h]dglu). stimulation of hexose transport in sindbis virus-infected cells occurred only if the cells were rendered quiescent by culturing at high density or by serum starvation. in contrast, sindbis virus-induced inhibition of potassium transport, measured as a decrease in the uptake of 86rb+, was independent of cell growth state. stimulat ...19863024395
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