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increased turnover of vaccinia virus-specific immediate early rnas in interferon-treated chick embryo fibroblasts.the synthesis and steady state level of immediate early vaccinia virus-specific rnas in interferon-treated chick embryo fibroblasts were determined by blot hybridization analysis using the cloned restriction endonuclease fragment pej 18 containing the gene of vaccinia virus wr-specific dna polymerase as a probe. even though early vaccinia virus wr rna was still synthesized, accumulation of immediate early viral rnas was strongly inhibited. accumulation of beta-actin rna was not affected. this in ...19872445663
characterization and epitope mapping of a human monoclonal antibody reactive with the envelope glycoprotein of human immunodeficiency virus.a human monoclonal antibody (igg2, lambda), 1b8.env, was produced, reactive with the envelope glycoprotein of human immunodeficiency virus (hiv). the antibody specifically stains cells infected with hiv, as assessed by indirect immunofluorescence analysis and reacts with determinants displayed on the surface of infected cells. in western blot analysis, the antibody reacts with bands of 160 and 41 kd, consistent with the precursor and transmembrane forms of the hiv envelope glycoprotein. the anti ...19872447158
molecular definition of a major cytotoxic t-lymphocyte epitope in the glycoprotein of lymphocytic choriomeningitis virus.analyses with segmental reassortants of lymphocytic choriomeningitis virus (lcmv) rna have shown that cytotoxic t lymphocytes (ctl) are induced by and recognize proteins encoded by the viral short segment, which specifies two virus structural proteins, glycoprotein (gp) and nucleoprotein (np). expression of cdna copies of these genes in vaccinia virus vectors demonstrates that c57bl/6 (h2bb) mice mount significant ctl responses to both gp and np. we have used lcmv-specific h2bb-restricted ctl cl ...19882448497
[potentiation of the antiviral activity of human interferons by virazole in in vitro experiments].combination of interferon and virazole results in potentiation of their antiviral activity. this was demonstrated with all three types of natural interferons and the recombinant rl-2-interferon. this effect is retained at a temperature of 37 degrees c and increases when the chemical drug is combined with a mixture of alpha- and gamma-interferon.19872448957
9-(trans-2',trans-3'-dihydroxycyclopent-4'-enyl)-adenine and -3-deazaadenine: analogs of neplanocin a which retain potent antiviral activity but exhibit reduced cytotoxicity.two synthetic analogs of neplanocin a, which were shown in a separate study to be inhibitors of s-adenosylhomocysteine hydrolase and devoid of substrate activity with adenosine kinase, were found in this study to inhibit vaccinia virus replication in murine l929 cells but to have reduced cytotoxicity compared with that of the parent compound. these results confirm that s-adenosylhomocysteine hydrolase is the molecular target which mediates the antiviral effects of neplanocin a and that transform ...19872449123
soluble antigens of vaccinia virus. note i. chemical and biological properties. immunogenic capacity. 19872449147
epitope mosaic on the surface proteins of orthopoxviruses.epitopes on the surface components of orthopoxviruses were analyzed with monoclonal antibodies (mabs) against monkeypox and vaccinia viruses by enzyme-linked immunosorbent assay (elisa), western blotting (wb), radioimmunoprecipitation (rip), and competitive binding inhibition assay (cbia). when compared by elisa, three vaccinia virus strains exhibited a similar reactivity to 99 tested mabs despite their remote passage history. all five isolates of monkeypox virus closely resembled one another, i ...19882450423
a soluble recombinant polypeptide comprising the amino-terminal half of the extracellular region of the cd4 molecule contains an active binding site for human immunodeficiency virus.infection of helper t lymphocytes by human immunodeficiency virus is initiated by a specific interaction of the viral envelope glycoprotein with cd4, an integral membrane glycoprotein of the target cell. we have adapted a vaccinia virus-based mammalian cell expression system to produce variants of the cd4 molecule for structure-function studies. in this report we demonstrate that a truncated 180-amino acid fragment representing approximately the n-terminal half of the extracellular region of cd4 ...19882451247
hiv-1 reverse transcriptase is a target for cytotoxic t lymphocytes in infected individuals.characterization of the host immune response to human immunodeficiency virus type 1 (hiv-1) is critical to the rational design of an effective aids vaccine. in this study, cytotoxic t lymphocytes (ctl) specific for hiv-1 reverse transcriptase (rna-dependent dna polymerase) were found in blood samples from hiv-1-infected individuals. ctl targets were prepared by immortalizing b cells from ten seropositive and six seronegative individuals, and then infecting these cells with recombinant vaccinia v ...19882451288
an immunodominant epitope of the human immunodeficiency virus envelope glycoprotein gp160 recognized by class i major histocompatibility complex molecule-restricted murine cytotoxic t lymphocytes.because cytotoxic t lymphocytes (ctl) may be important for preventing direct cell-to-cell transmission of human immunodeficiency virus (hiv), the agent responsible for acquired immunodeficiency syndrome, we have begun to investigate the epitope specificity and immune response (ir) gene control of anti-hiv ctl responses in experimental animals. mice were infected with a recombinant vaccinia virus expressing the hiv gp160 envelope gene, and the primed lymphocytes were restimulated in vitro with a ...19882452443
protection against lethal influenza with neuraminidase.the role of the neuraminidase in eliciting protection against a lethal influenza a virus [a/ck/penn/1370/83 (h5n2)] infection was investigated in chickens. isolated n2 neuraminidase administered in adjuvant did not prevent infection but did prevent systemic spread of virus and death of chickens. n2 expressed in a recombinant vaccinia virus protected chickens when administered in adjuvant but was less effective when allowed to replicate and produce pox on the chicken's comb. chickens vaccinated w ...19882452514
human class i mhc-restricted cytotoxic t-lymphocytes specific for human immunodeficiency virus envelope antigens.vaccines incorporating hiv envelope antigens are being developed for the prevention of aids. to determine whether hiv envelope antigens are recognized by human cytotoxic t-lymphocytes (ctl), we assessed class i mhc-restricted, hiv envelope antigen-specific cytotoxic activity of peripheral blood mononuclear cells (pbmc) from hiv-infected individuals, following in vitro stimulation. the target cells were human skin fibroblasts of known tissue type, infected with recombinant vaccinia viruses, eithe ...19882454643
cytotoxic t cells specific for the circumsporozoite protein of plasmodium falciparum.malaria is initiated by the inoculation of a susceptible host with sporozoites from an infected mosquito. the sporozoites enter hepatocytes and develop for a period as exoerythrocyte or hepatic stage parasites. vaccination with irradiated sporozoites can provide protective immunity and a recent study shows that this can also be conferred by immunization with a recombinant salmonella expressing only the circumsporozoite protein that normally covers the sporozoites. protection against infection is ...19882456467
efficacy of influenza haemagglutinin and nucleoprotein as protective antigens against influenza virus infection in mice.influenza nucleoprotein (np)-specific cytotoxic t lymphocytes (ctl) stimulated by immunization of mice with vv-pr8-np6, a recombinant vaccinia virus expressing a/pr/8/34 np, did not protect mice against challenge with a/pr/8/34 4 days later. neither were secondary np-specific ctl stimulated by reimmunization able to protect mice. these results contrast with the ability of transferred, in vitro-cultured and stimulated, np-specific ctl to protect recipient mice from challenge with a/pr/8/34. immun ...19882456608
antigenic peptides recognized by t lymphocytes from aids viral envelope-immune humans.t-lymphocyte immunity is likely to be an important component of the immune defence against the aids virus, because helper t cells are necessary for the antibody response as well as the cytotoxic response. we have previously predicted two antigenic sites of the viral envelope protein gp120 likely to be recognized by t lymphocytes, based on their ability to fold as amphipathic helices, and have demonstrated that these are recognized by t cells of mice immunized with gp120 (ref. 1). a peptide corre ...19882457809
effects of anti-gp120 monoclonal antibodies on cd4 receptor binding by the env protein of human immunodeficiency virus type 1.monoclonal antibodies (mabs) to defined peptide epitopes on gp120 from human immunodeficiency virus type 1 were used to investigate the involvement of their epitopes in gp120 binding to the cd4 receptor. recombinant vaccinia viruses were constructed that expressed either full-length gp120 (v-ed6), or a truncated gp120 lacking 44 amino acids at the carboxyl terminus (v-ed4). binding of these glycoproteins to the cd4 receptor was detected directly with metabolically labeled gp120 or indirectly wit ...19882458487
site-specific mutations in vectors that express antigenic and temperature-sensitive phenotypes of the m gene of vesicular stomatitis virus.full-length cdna copies of mrnas coding for the matrix (m) proteins of vesicular stomatitis virus and its mutant tso23(iii) were cloned in pbsm13- (bluescribe). the authenticity of these clones was demonstrated by restriction enzyme mapping, dna sequencing, and in vitro transcription and translation to identify the two m proteins by western immunoblotting with epitope-specific monoclonal antibodies. site-directed mutants were constructed by primer extension of synthetic oligodeoxynucleotides wit ...19882458488
immunopharmacological activities of chemically synthesized lipid a-subunit analogue gla-27 combined with muramyl dipeptide via spacers of different carbon chain length.a lipid a-subunit analogue gla-27, a 4-o-phosphono-d-glucosamine derivative carrying 3-o-tetradecanoyl and n-3-tetradecanoyloxytetradecanoyl groups, exhibited significant biological activities but no detectable pyrogenicity or local shwarzman activity. in order to synthesize compounds combining gla-27 with muramyl dipeptide (mdp), the oh group at the c6 position of gla-27 was first succinylated. a compound which combined a succinylated gla-27 (gla-101) with 1-deoxy n-acetyl-muramyl-l-alanyl-d-is ...19882459075
defective presentation to class i-restricted cytotoxic t lymphocytes in vaccinia-infected cells is overcome by enhanced degradation of antigen.vaccinia infection interferes with the presentation of influenza haemagglutinin (ha) and nucleoprotein (np) to class i-restricted ctl. the inhibitory effect is selective for certain epitopes, and is more profound during the late phase of infection. for influenza a/nt/60/68 np, the block is present during both early and late phases of infection, and is selective for the cooh-terminal epitope defined by peptide 366-379, having no detectable effect on the presentation of the nh2-terminal epitope 50 ...19882459295
molecular basis for cytolytic t-lymphocyte recognition of the murine cytomegalovirus immediate-early protein pp89.the murine cytomegalovirus protein pp89, which is encoded by gene iei, is a nonstructural regulatory protein expressed in the immediate-early phase of the viral replication cycle and located mainly in the nucleus of infected cells. protection of balb/c (h-2d) mice against a lethal murine cytomegalovirus challenge infection is achieved by vaccination with a recombinant vaccinia virus, mcmv-iei-vac, expressing pp89 as the only murine cytomegalovirus gene product. the protection is entirely mediate ...19882459408
characterization of human immunodeficiency virus gag/pol gene products expressed by recombinant vaccinia viruses.recombinant vaccinia viruses containing either the entire gag/pol gene or the reverse transcriptase (rt) domain of the human immunodeficiency virus (hiv) were constructed. in mammalian cells infected with the recombinant vaccinia virus containing the gag/pol gene, major and minor polypeptides of 55 and 41 kda were made, but processed gag products (p24/p17/p15) were not detected. in addition, none of the products of the pol open-reading frame were seen. both the 55- and 41-kda gag proteins were p ...19882459842
class i mhc-restricted recognition of cells expressing a gene encoding a 41 amino acid product of the influenza hemagglutinin.class i h-2kd-restricted influenza hemagglutinin (ha)-specific ctl recognize two immuno-dominant sites as represented by synthetic peptides spanning epitopes located in the ha1 and hydrophobic transmembrane domains of the influenza ha. using a vaccinia virus recombinant expression system, we have examined ctl recognition of ha deletion mutants expressed in target cells. we have demonstrated that a truncated influenza ha gene encoding only the transmembrane anchor region containing a class i reco ...19882460530
group-specific, major histocompatibility complex class i-restricted cytotoxic responses to human immunodeficiency virus 1 (hiv-1) envelope proteins by cloned peripheral blood t cells from an hiv-1-infected individual.freshly separated unfractionated peripheral blood mononuclear cells (pbmc) and cloned cell lines from a healthy human immunodeficiency virus 1 (hiv-1)-seropositive individual were examined for cytotoxic responses to hiv proteins expressed by recombinant vaccinia viruses. it was found that freshly isolated pbmc recognize variant envelope proteins of hiv-1 but not a more distantly related envelope protein derived from the simian immunodeficiency virus (sivmac). although the effector cells were pre ...19882460873
a region of the influenza a/nt/60/68 pb2 protein containing an antigenic determinant recognized by murine h-2dd restricted cytotoxic t lymphocytes.we have used a recombinant vaccinia virus to investigate the recognition of the pb2 protein of influenza a/nt/60/68 (h3n2) by murine polyclonal ctl populations. pb2 is recognized as a major cross-reactive target antigen. recognition of pb2 is under strict genetic control, since balb/c (h-2d) but not cba (h-2k) mice are responders. we also demonstrate, by use of cell lines transfected with individual genes encoding class i molecules of the h-2d haplotype, that recognition of pb2 occurs in conjunc ...19882460995
hiv-1 gag-specific cytotoxic t lymphocytes defined with recombinant vaccinia virus and synthetic peptides.current candidate vaccines fail to protect primates against challenge with human immunodeficiency virus (hiv) in the presence of antibody responses; this underlines the importance of studying cell-mediated immunity to hiv and identifying specific epitopes that stimulate cytotoxic t lymphocytes (ctl). using a recombinant vaccinia virus to express the gag protein of hiv-1 we found hla class-i-restricted gag-specific ctl in thirteen out of fifteen healthy hiv seropositive patients. we then used sho ...19882461519
binding region for human immunodeficiency virus (hiv) and epitopes for hiv-blocking monoclonal antibodies of the cd4 molecule defined by site-directed mutagenesis.the binding region for human immunodeficiency virus (hiv) and epitopes for a panel of hiv-blocking anti-cd4 monoclonal antibodies of the cd4 molecule were defined by using in vitro site-directed mutagenesis. codons for two amino acid residues (ser-arg) were inserted at selected positions within the region encoding the first and second immunoglobulin-like domains of cd4. a vaccinia virus-based expression system was used to produce soluble full-length extracellular cd4 fragments containing the ins ...19882461565
recombinant vaccinia/venezuelan equine encephalitis (vee) virus expresses vee structural proteins.cdna molecules encoding the structural proteins of the virulent trinidad donkey and the tc-83 vaccine strains of venezuelan equine encephalitis (vee) virus were inserted under control of the vaccinia virus 7.5k promoter into the thymidine kinase gene of vaccinia virus. synthesis of the capsid protein and glycoproteins e2 and e1 of vee virus was demonstrated by immunoblotting of lysates of cv-1 cells infected with recombinant vaccinia/vee viruses. vee glycoproteins were detected in recombinant vi ...19882462013
capped poly(a) leaders of variable lengths at the 5' ends of vaccinia virus late mrnas.evidence for capped poly(a) leaders of variable lengths located immediately upstream of the translation initiation codon was obtained by direct analyses of a major late mrna species. a decapping-recapping method was used to specifically substitute a radioactively labeled phosphate for an unlabeled one within the cap structure. rnase h-susceptible sites were made by hybridizing synthetic oligodeoxyribonucleotides to the mrna encoding a late major structural protein of 11 kilodaltons. sequences of ...19892462059
molecular characterization of a prominent antigen of the vaccinia virus envelope.during vaccinia virus (vv) assembly a major polypeptide migrating with an apparent mw of 35k, designated ag35, is expressed as an early function and becomes an integral component of the lipoprotein envelope surrounding the mature virion. in a previous study evaluating humoral immunity to vv, a prominent response against ag35 was invariably detected in immunized mice. in the context of our continuing investigations of the structure and function of the vaccinia envelope, with a view to alteration ...19882462305
spleen natural killer cells from iron-deficient rat pups manifest an altered ability to be stimulated by interferon.the effect of in vitro interferon stimulation on nonimmune- and immune-spleen natural killer cell activity was studied in iron-deficient rat pups. dams were fed 6, 12 or 250 mg fe/kg diet during gestation and lactation. approximately one-half of the 17-d-old pups were injected intraperitoneally with 10(5) plaque-forming units of vaccinia virus. four d later, nonimmune and vaccinia-immune pups were killed. spleen lymphocyte suspensions were prepared and plated with or without rat alpha/beta inter ...19882463345
expression and processing of human immunodeficiency virus type 1 gag and pol genes by cells infected with a recombinant vaccinia virus.human cells infected with a recombinant vaccinia virus containing human immunodeficiency virus type 1 gag-pol genes produced large amounts of human immunodeficiency virus gag proteins beginning at 1 h and peaking at 48 h postinfection. we show that these polyproteins are processed accurately into mature forms and that the viral polymerase gene is encoded as a 160-kilodalton gag-pol fusion protein, most likely by translational frameshifting from the gag into the pol reading frame.19892464705
enhancement of nonspecific resistance to viral infection by chemically synthesized lipid a-subunit analogs with different backbone structures and acyl groups.protection against vaccinia virus infection and induction of interferon (ifn) were investigated in propionibacterium acnes-primed mice following treatment with chemically synthesized lipid a-subunit derivatives. the antiviral activity was based on the reduction of numbers of tail lesions in mice injected intravenously with the test compounds 1 day before virus infection. gla-27, a 4-o-phosphono-d-glucosamine carrying 3-o-tetradecanoyl (c14) and n-3-tetradecanoyloxytetradecanoyl [c14-o-(c14)] gro ...19882465734
induction and activity of class ii-restricted, lyt-2+ cytolytic t lymphocytes specific for the influenza h5 hemagglutinin.in influenza a virus infections, ctl are a significant component of the host immune response which limits viral replication and promotes recovery. to examine the ctl response to the influenza virus a/ty/ont/7732/66[h5n9], particularly the h5 hemagglutinin, a long term ctl line was generated from spleen cells of a/ty/ont-immune balb/c [h-2d] mice secondarily stimulated in vitro with a/ty/cal/hurst-2/71[h5n2]. this ctl line was highly specific for influenza viruses of the h5 subtype. from this lin ...19892466897
class i mhc-restricted cytotoxic t cells efficiently recognize haemagglutinin that is defective in protein folding and cell surface expressions.cytotoxic t-cell recognition of an engineered variant of the influenza viral haemagglutinin (ha), expressed in vaccinia virus, was investigated. we show that the insertion of a foot-and-mouth disease virus (fmdv) immunogenic peptide into the ha results in major disruption of its higher order structure with intracellular rather than cell surface localization accompanying the loss of conformational epitopes detected by antibody. in contradistinction to antibody, recognition of the chimaeric molecu ...19882467191
anti-viral protection and prevention of lymphocytic choriomeningitis or of the local footpad swelling reaction in mice by immunization with vaccinia-recombinant virus expressing lcmv-we nucleoprotein or glycoprotein.the viral antigen specificity of primary cytotoxic t cell responses (ctl) of h-2b, h-2k, h-2q, h-2s, h-2f and some h-2-recombinant mice against lymphocytic choriomeningitis virus (lcmv-we isolate) as well as the specificity of some ctl clones and t cell lines was defined on target cells infected with vaccinia-recombinant virus expressing nucleoprotein (np) or glycoprotein (gp). np was recognized together with h-2q (dq), h-2d (dld), h-2s and h-2b (db). gp specificity was restricted to h-2f and h- ...19892468501
human and murine cd4 t cell epitopes map to the same region of the malaria circumsporozoite protein: limited immunogenicity of sporozoites and circumsporozoite protein.the circumsporozoite (cs) protein is a candidate vaccine antigen for the sporozoite stage in the life cycle of the malaria parasite. using cs protein purified from recombinant baculovirus-infected cells and a panel of h-2 congenic mice, we are able to demonstrate that this protein is poorly immunogenic in terms of antibody production as a result of ir gene control. the immune response to the protein is also restricted following immunization with a cs-recombinant vaccinia virus or with sporozoite ...19882468986
[the coagglutination reaction with arbo- and arenaviruses]. 19882470204
cell-mediated immune proliferative responses to hiv-1 of chimpanzees vaccinated with different vaccinia recombinant viruses.the only animal that can be reproducibly infected with hiv, and that thus provides an experimental system for testing the effectiveness of prototype vaccines, is the chimpanzee. we compared proliferative responses to hiv and to vaccinia virus (vv) antigens of lymphocytes taken at various times from chimpanzees vaccinated with recombinant vv expressing different hiv genes. animals were immunized with the original vv strain, as control, or with constructs expressing gp160 (vv160) given exclusively ...19892470398
antiviral t cell competence and restriction specificity of mixed allogeneic (p1 + p2----p1) irradiation chimeras.mixed irradiation bone marrow chimeras were prepared by reconstituting lethally irradiated c57bl/10 (b10) or b10.d2 mice with t cell-depleted bone marrow cells of b10 plus b10.d2 origin. these chimeras were healthy and survived well under conventional housing conditions and after experimental laboratory infections. of a total of 17 chimeras tested, 2 died spontaneously or from the injected virus. twelve of fifteen chimeras mounted a measurable cytotoxic t cell response to virus. despite approxim ...19892470518
epitope mapping by deletion mutants and chimeras of two vesicular stomatitis virus glycoprotein genes expressed by a vaccinia virus vector.deletion mutants and chimeras of the glycoprotein (g) genes of vesicular stomatitis virus serotypes indiana (vsv-ind) and new jersey (vsv-nj) were cloned in plasmids and vaccinia virus vectors under control of the bacteriophage t7 polymerase promoter for expression in cv-1 cells co-infected with a t7 polymerase-expressing vaccinia virus recombinant. truncated and chimeric g proteins expressed by these vectors were tested for their capacity to react with vsv-ind and vsv-nj epitope-specific monocl ...19892471352
recognition of respiratory syncytial virus fusion protein by mouse cytotoxic t cell clones and a human cytotoxic t cell line.two mouse cytotoxic t cell (tc) clones, d5 and h11a, with specificity for the respiratory syncytial virus (rsv) fusion protein (f) were derived from balb/c mice primed intranasally (i.n.) with rsv (a2 strain). these clones possessed essentially the same characteristics, and only clone h11a is described here. tc clone h11a lysed target cells infected with a recombinant vaccinia virus (vv) expressing the rsv f gene, and similar target cells infected with rsv strains long, 8/60, or 18537. in additi ...19892471784
sulfated polysaccharides are potent and selective inhibitors of various enveloped viruses, including herpes simplex virus, cytomegalovirus, vesicular stomatitis virus, and human immunodeficiency virus.several sulfated polysaccharides (dextran sulfate, pentosan polysulfate, fucoidan, and carrageenans) proved to be potent inhibitors for herpes simplex virus, human cytomegalovirus, vesicular stomatitis virus, sindbis virus, and human immunodeficiency virus. they were moderately inhibitory to vaccinia virus but not inhibitory to adenovirus, coxsackievirus, poliovirus, parainfluenza virus, and reovirus. these results indicate that, with the exception of parainfluenza virus, enveloped viruses are s ...19882472775
expression of biologically active human chorionic gonadotropin and its subunits by recombinant vaccinia virus.vaccinia virus (vv) expression vector was used to clone the genes for coding alpha and beta subunits of human chorionic gonadotropin (hcg). recombinant viruses vsl3 and vss1 containing these genes were selected as blue coloured plaques on the basis of co-expression of escherichia coli beta-galactosidase in the infected cells. cv-1 cells when infected with vsl3 or vss1 secreted 2.4 and 1.8 micrograms of alpha and beta hcg subunits, respectively, per 3 x 10(6) cells after 24 h of infection. the su ...19892473009
[experimental detection of the paraspecific effects of purified and inactivated poxviruses].the paraspecific effect of pox viruses i.e. stimulation of the nonspecific part of the complex immune system, was demonstrated in vitro and in vivo for 3 different types of virus (vaccinia virus, avipox virus, parapox virus). by means of purification, concentration and inactivation, it was possible to prove that the paraspecific effect is brought about by the pox virus particle per se. the effect is induced by certain epitopes in the complex structure of the virus and is independent of virus mul ...19892473583
gp38, p28-i and p28-ii: candidates for a vaccine against schistosomiasis.three antigens protective against schistosoma mansoni have been extensively characterized. the schistosomulum surface antigen gp38 possesses an immunodominant carbohydrate epitope of which the structure has been defined. protection can be achieved via the transfer of monoclonal antibodies recognizing the epitope or by immunization with anti-idiotype monoclonal antibodies. the glycan epitope is shared with the intermediate host, biomphalaria glabrata as well as being present on other molluscs, in ...19872474122
structural features of t-cell recognition: applications to vaccine design.t lymphocytes, in contrast to antibodies, appear to recognize primarily a limited number of antigenic sites on any given antigenic protein. we find that a single site can so dominate the t-cell repertoire that the presence or absence of a response to one immunodominant site can make the difference between a high responder and a low responder, even though low responders respond to other sites almost as well as high responders. besides interaction with major histocompatibility complex (mhc) molecu ...19892474171
recombinant vaccinia virus expresses immunoreactive alpha subunit of ovine luteinizing hormone which associates with beta-hcg to generate bioactive dimer. 19882475429
a 15 amino acid fragment of influenza nucleoprotein synthesized in the cytoplasm is presented to class i-restricted cytotoxic t lymphocytes.a recombinant vaccinia has been designed to express amino acids 366-379 of influenza nucleoprotein, previously shown to be the minimal epitope recognized by a class i-restricted cytotoxic t cell clone. target cells infected with the recombinant vaccinia virus expressing this peptide are recognized by ctl as efficiently as target cells expressing the complete nucleoprotein. the results imply the existence of a peptide transport system that constitutively passes the products of degraded proteins f ...19892475569
identification of factors specific for transcription of the late class of vaccinia virus genes.cytoplasmic extracts made from hela cells that have been harvested late after infection with vaccinia virus are capable of specifically transcribing templates containing vaccinia virus late-gene promoters. we applied such an extract to a phosphocellulose column and eluted the proteins with a series of buffers containing successively higher concentrations of nacl. none of three column fractions alone was capable of specific transcription of a late-gene template. however, specific transcriptase ac ...19892476568
molecular analyses of a five-amino-acid cytotoxic t-lymphocyte (ctl) epitope: an immunodominant region which induces nonreciprocal ctl cross-reactivity.the cytotoxic t-lymphocyte (ctl) response to lymphocytic choriomeningitis virus infection determines the outcome of infection. here we show that this response in balb/c mice (h-2d), when analyzed both at the primary ctl level and using ctl clones, is predominantly monospecific. the vast majority of ctl have a common specificity for a single epitope in the virus nucleoprotein, which can be minimally identified by amino acids gvymg. this epitope is presented by the ld class i glycoprotein. we used ...19892476570
molecularly engineered vaccine which expresses an immunodominant t-cell epitope induces cytotoxic t lymphocytes that confer protection from lethal virus infection.identification of a single viral t-cell epitope, associated with greater than 95% of the virus-specific cytotoxic t-lymphocyte (ctl) activity in balb/c (h-2d) mice (j. l. whitton, a. tishon, h. lewicki, j. gebhard, t. cook, m. salvato, e. joly, and m. b. a. oldstone, j. virol. 63:4303-4310, 1989), permitted us to design a ctl vaccine and test its ability to protect against a lethal virus challenge. here we show that a single immunization with a recombinant vaccinia virus-lymphocytic choriomening ...19892476571
expression of drosophila shaker potassium channels in mammalian cells infected with recombinant vaccinia virus.a recombinant vaccinia virus containing a drosophila potassium channel (shaker h4) cdna was constructed by homologous recombination between wild-type vaccinia virus dna and a transfer plasmid. the new virus was used to infect four types of mammalian cells in culture. electrophysiological recording 24-72 hr after infection revealed the expression of voltage-gated transient potassium channels in all four cell types. the properties of the induced currents were identical to those previously observed ...19892477844
resistance of vaccinia virus to interferons: modulation of the 2-5a system in interferon-treated, vaccinia virus infected cells.in this study we have examined if resistance of vaccinia virus to interferon (ifn) correlates with virus-induced alterations of the 2-5a system. we have shown that in various ifn-treated vaccinia virus infected cells of mouse, monkey and human origins, the intracellular levels of 2-5a are low early in infection but exhibit a sharp rise late in infection. in spite of the presence of 2-5a, activation of the 2-5a dependent rnase, as measured by the rrna cleavage assay, does not occur or is delayed ...19872478164
human immunodeficiency virus-like particles produced by a vaccinia virus expression vector.infectious retrovirus particles consist of a core structure containing rna and gag-pol polypeptides surrounded by a lipid membrane studded with env proteins. a recombinant vaccinia virus was designed to express the entire gag-pol precursor protein of the human immunodeficiency virus type 1. synthesis and processing of gag proteins occurred in mammalian cells infected with this live recombinant virus, and reverse transcriptase was detected largely in the medium. electron micrographs revealed imma ...19892479031
analgesic mechanism of neurotropin: relation to the serotonergic system and influence of spinal cord transection.neurotropin, a nonprotein component extracted from the skin of rabbits treated with vaccinia virus, has been clinically and experimentally reported to demonstrate analgesic effects. in this study, we investigated the antinociceptive action of neurotropin in relation to the serotonergic system, a pain inhibitory system, and substance p, a pain transmitter; we also attempted to determine whether it acts at the spinal or supraspinal level in mice. 1) the spinal cord (t6-t10) transection completely ...19892480465
long-term culture and fine specificity of human cytotoxic t-lymphocyte clones reactive with human immunodeficiency virus type 1.the definition of human immunodeficiency virus type 1 (hiv-1) immunogenic epitopes is central to the rational design of aids vaccine strategies. in this study, we have generated seven hiv-1 reverse transcriptase-specific cytotoxic t-lymphocyte (ctl) clones from the peripheral blood of two seropositive subjects. epitopes recognized by these ctl clones were identified by using target cells infected with recombinant hiv-1-vaccinia virus vectors expressing truncated reverse transcriptase proteins an ...19892480604
structural basis for epidermal growth factor receptor function.the receptor for epidermal growth factor (egf) has been the subject of intense study primarily as a consequence of the pioneering studies of cohen on growth factors and also because of its homology to the transforming protein encoded by the avian oncogene v-erbb, which is a truncated receptor and its consequent role in cancer. although similar structural mutation of the egf receptor has not yet been found in human tumours, aberrant overexpression of both egf receptors and c-erbb2, a closely rela ...19892491253
expression of hepatitis b core antigen gene in recombinant vaccinia virus.plasmid pmm2066 was digested with ecori restriction enzyme and an 870 bp fragment separated; it was located 12 bp upstream from the atg codon of the antigen c structural gene. this dna fragment was then inserted into shuttle vector pgjp-5 just downstream from the p7.5 promoter, producing recombinant vector p5-c2066. three tk- recombinant vaccinia viruses expressing hbcag were isolated by plaque assay, using homologous recombination in tk- 143 cells in the presence of budr. the supernatant from c ...19892491322
vaccinia-interleukin 2 recombinant virus or exogenous interleukin 2 does not alter the magnitude or immune response gene defects of the cytotoxic t-cell response to vaccinia virus in vivo.we investigated the role of interleukin 2 (il-2), a t cell-derived lymphokine, in the generation of in vivo cytotoxic t-cell responses to vaccinia virus. we made use of a recombinant vaccinia virus encoding and expressing the murine il-2 gene and recombinant il-2 to test the role of il-2 in the expression of major histocompatibility complex (mhc) class i determined immune response (ir) gene defects in the response to vaccinia virus. il-2 expressed either by the vaccinia virus vector or exogenous ...19892493675
structure and stability of mrna synthesized by vaccinia virus-encoded bacteriophage t7 rna polymerase in mammalian cells. importance of the 5' untranslated leader.we have analyzed the structure and stability of rna synthesized by bacteriophage t7 rna polymerase in mammalian cells. the t7 polymerase, expressed by a recombinant vaccinia virus, transcribed the escherichia coli lacz gene flanked by t7 promoter and terminator signals. the lacz gene cassette was introduced into infected cells within either a transfected plasmid or a second recombinant vaccinia virus. the t7-lacz transcripts, which had a half-life of approximately 75 minutes, represented approxi ...19892497259
differential effects of epidermal growth factor, transforming growth factor-alpha, and vaccinia virus growth factor in the positive regulation of ifn-gamma production.we have recently shown that epidermal growth factor (egf) is capable of positive regulation of ifn-gamma production, thus establishing a functional relationship between nonhemopoietic growth factors and the immune system. in order to study this relationship further, egf and the egf-related growth factors transforming growth factor-alpha (tgf-alpha) and vaccinia virus growth factor (vgf), which stimulate cellular proliferation via binding to the egf receptor, were studied for their functional and ...19892499624
induction of cell surface expression of hla antigens by human ifn-gamma encoded by recombinant vaccinia virus.a recombinant vaccinia virus (vv) encoding human ifn-gamma (vv-huifn-gamma) was constructed and its effects on mhc ag expression in human and murine cells in vitro analyzed by flow cytometry. at high multiplicities of infection (5 pfu/cell) the ifn-gamma expressed by vaccinia was not able to overcome the profound decrease of mhc concentration, normally associated with vv infection, in any of the cells tested. however, at successively decreasing multiplicities of infection, a gradual increase in ...19892500483
human nadph-p450 oxidoreductase: complementary dna cloning, sequence and vaccinia virus-mediated expression and localization of the cypor gene to chromosome 7.the cdna containing the full coding sequence of human nadph-p450 oxidoreductase was isolated and completely sequenced. the cdna contained 2398 base pairs, including 9 and 358 base pairs of 5' and 3' noncoding sequences, respectively. the human nadph-p450 oxidoreductase protein deduced from the cdna has 677 amino acids, with a calculated molecular weight of 76,656. the cdna nucleotide and deduced amino acid sequences displayed 83 and 92% similarities, respectively, with those of the rat nadph-p45 ...19892501655
target cell lysis by natural killer cells is influenced by beta 2-microglobulin expression.natural killer (nk) cells form part of the vertebrate defence against viruses and tumours, but show only limited specificity. the molecule(s) recognized by nk cells on target cells are at present unknown. major histocompatibility complex (mhc) class i antigen concentration on target cells is inversely correlated with nk cell lysis. here we show that mhc class i-unassociated beta 2-microglobulin (beta 2-m) expression is involved in nk cell-target cell interaction. two human mhc class i negative c ...19892502830
biologicals production by recombinant dna technology in cuba.during 1981 we started an intensive programme for the development of biotechnology in cuba. the first project was related to the production of leucocyte interferon and the cloning an expression of these genes in prokaryotic and yeast cells. these products are currently obtained in large amounts and their physical and chemical characterization are presented. the use of mammalian cells in culture for the production of recombinant proteins has also been carried out. the results obtained with the ex ...19892503409
site of the base change in the vaccinia virus dna polymerase gene which confers aphidicolin resistance.an aphidicolin-resistant mutant of vaccinia virus has been shown to encode an altered viral dna polymerase that is more resistant to aphidicolin. marker transfer experiments with the dna from the resistant virus localized the mutation site to an rsai segment within the portion of the hindiii-e segment which has been shown to contain the viral dna polymerase gene. nucleotide sequence analysis of the mutant dna showed a single gc to at transition at position 2430, which indicates a leucine-to-meth ...19892503622
[mechanisms of disruption of dna in human cells. mutagenesis of a virus in xeroderma pigmentosum cells as an indicator of a defect in dna repair].lymphocytes of two patients with xeroderma pigmentosum, their mothers and cell lines isolated from the third patient were examined. the reaction of vaccinia virus treated with mutagens, the index of virus-induced mutagenesis and dna repair synthesis were the criteria of estimation of cell repair activity. significant inhibition of dna repair synthesis was detected in cells of all the patients observed (primary and established lines) in the experiments with uv-irradiation and 4-nitroquinoline-4-o ...19892509286
humoral immune response elicited by highly attenuated variants of vaccinia virus and by an attenuated recombinant expressing hiv-1 envelope protein.attenuated variants of vaccinia virus have excellent potential for the construction of safe recombinant live vaccines. in this investigation, highly attenuated variants of vaccinia virus with several genetic markers and a variant recombinant were tested in balb/c mice for their ability to induce humoral immune response. mice primed with variants that had an 8-mda deletion at the left end of the viral genome induced similar levels of circulating anti-vaccinia antibodies as the wild-type virus. ho ...19892510402
tumor cells treated with vaccinia virus can activate the alternative pathway of mouse complement.vaccinia virus has been shown to render mouse tumor cells highly immunogenic. since we have demonstrated that induction of complement activating capacity on guinea pig tumor cells by sendai virus infection causes the tumor cells to become immunogenic, we assumed that vaccinia virus infection of mouse tumor cells might render them reactive with homologous mouse complement. therefore, murine tumor cells, mh134 and x5563, infected with vaccinia virus (vv) were incubated with mouse plasma and c3 dep ...19892511185
dengue virus-specific cross-reactive cd8+ human cytotoxic t lymphocytes.stimulation with live dengue virus of peripheral blood mononuclear cells from a dengue virus type 4-immune donor generated virus-specific, serotype-cross-reactive, cd8+, class i-restricted cytotoxic t lymphocytes (ctl) capable of lysing dengue virus-infected cells and cells pulsed with dengue virus antigens of all four serotypes. these ctl lysed autologous fibroblasts infected with vaccinia virus-dengue virus recombinant viruses containing the e gene or several nonstructural dengue virus type 4 ...19892511337
structure of vaccinia virus early promoters.functional elements of a vaccinia virus early promoter were characterized by making a complete set of single nucleotide substitutions, as well as more complex mutations, and assaying their effects on gene expression. synthetic oligonucleotides, based primarily on the sequence of the 7.5-kd early promoter, were inserted into a plasmid vector containing the lacz gene of escherichia coli flanked by sequences from the thymidine kinase (tk) gene of vaccinia virus. the lacz gene, under control of the ...19892515286
structure of vaccinia virus late promoters.functional elements of vaccinia virus late promoters were characterized by mutagenesis. synthetic oligonucleotides were inserted into a plasmid vector containing the lacz gene of escherichia coli flanked by sequences from the thymidine kinase (tk) gene of vaccinia virus. the lacz gene, under control of the synthetic promoter, was introduced into the vaccinia virus genome at the tk locus by homologous recombination, and each of the 122 recombinants thus obtained was assayed for beta-galactosidase ...19892515287
role of lymphokine-secreting cd8+ t cells in cytotoxic t lymphocyte responses against vaccinia virus.the present study has examined the relative role of cd4+ and cd8+ th cells in the generation and reactivation of antivaccinia virus memory ctl responses. we show that mice primed in vivo to vaccinia virus generate in vitro antivaccinia virus memory ctl responses through both cd4+ and cd8+ th cell pathways, with the cd4+ th pathway being the more prominent of the two. in addition, we show that vaccinia virus-specific cd8+ th cell function is mediated through production of lymphokines, including i ...19892521235
proper processing of dengue virus nonstructural glycoprotein ns1 requires the n-terminal hydrophobic signal sequence and the downstream nonstructural protein ns2a.expression of dengue virus gene products involves specific proteolytic cleavages of a precursor polyprotein. to study the flanking sequences required for expression of the dengue virus nonstructural glycoprotein ns1, we constructed a series of recombinant vaccinia viruses that contain the coding sequence for ns1 in combination with various lengths of upstream and downstream sequences. the ns1 products expressed by these viruses in infected cv-1 cells were immune precipitated and analyzed by sodi ...19892522997
human immunodeficiency virus-specific cytotoxic responses of seropositive individuals: distinct types of effector cells mediate killing of targets expressing gag and env proteins.by using target cells that expressed isolated env, gag, p27nef, or p23vif molecules introduced by recombinant vaccinia viruses containing genes encoding these polypeptides, it was possible to identify env, gag, p27nef, and p23vif as cytolytic target antigens for freshly isolated blood cells from human immunodeficiency virus 1 (hiv-1) seropositive patients. most of the patients tested (95%) manifested a specific cytotoxic activity against vaccinia virus-env-infected target cells. the env-specific ...19892522999
genetic evidence for involvement of vaccinia virus dna-dependent atpase i in intermediate and late gene expression.to delineate the role of the vaccinia virus-encapsidated dna-dependent atpase i in the life cycle of the virus, we performed a detailed study of two temperature-sensitive mutants with lesions in the gene encoding the enzyme. profiles of viral dna and protein accumulation during infection showed the mutants to be competent for dna synthesis but deficient in late protein synthesis, confirming their defective late phenotype (r. c. condit and a. motyczka, virology 113:224-241, 1981: r. c. condit, a. ...19892527312
[significance of priming of hosts with virus in the tumor-specific immunotherapy model utilizing virus-reactive helper t cell activity].a tumor-specific immunotherapy model was established utilizing vaccinia virus (vv) in the consideration of clinical application, in which we assessed the significance of priming of hosts with vv to induce in vivo anti-tumor immunity. c3h/hen mice were pretreated with cyclophosphamide (cy) to eliminate non-specific suppressor t cell activity and subsequently inoculated (primed) subcutaneously (s.c.) with 10(7)pfu of vv, leading to augmented induction of vv-reactive helper t (vv-th) cell activitie ...19892528599
impaired generation of anti-viral cytotoxicity against lymphocytic choriomeningitis and vaccinia virus in mice treated with cd4-specific monoclonal antibody.the role of cd4+ helper t cells in induction of anti-viral cytotoxic t-cell response was investigated by treating normal and thymectomized c57b1/6 mice with cd4-specific monoclonal antibodies (moab). in cd4-specific moab-treated mice infected with vaccinia or lymphocytic choriomeningitis virus (lcmv), cytotoxic t-cell activity was 5-15 times lower than in normal controls when measured in a 51cr release assay and computed as lytic units 6 and 8 days respectively after virus inoculation. this diff ...19892532394
t-cells in respiratory syncytial virus (rsv) infection. 19892533461
synthesis and cytostatic and antiviral activities of 1-beta-d-ribofuranosyl-5-alkylcytosine (5-alkylcytidine) cyclic 3',5'-monophosphates.a series of 5-alkylcytidines and their 5'-monophosphates and cyclic 3',5'-monophosphates have been synthesized and evaluated for antiviral and antitumor activity. the 5-alkyl cyclic nucleotides were not cytostatic (id50 greater than 200 micrograms/ml) against leukemia l1210 cells and a deoxycytidine kinase-deficient subline thereof. certain of the corresponding nucleosides and their 5'-monophosphates did show activity within the range of 35-162 micrograms/ml, as did the unsubstituted cytidine cy ...19892535876
antigenic specificity of antibody-dependent cell-mediated cytotoxicity directed against human immunodeficiency virus in antibody-positive sera.antibody-dependent cell-mediated cytotoxicity (adcc) specific for human immunodeficiency virus (hiv) has been described for hiv-infected individuals. to determine the antigenic specificity of this immune response and to define its relationship to the disease state, an adcc assay was developed using epstein-barr virus-transformed lymphoblastoid cell line targets infected with vaccinia virus vectors expressing hiv proteins. the vaccinia virus vectors induced appropriate hiv proteins (envelope glyc ...19892536094
expression of the human immunodeficiency virus envelope glycoprotein is restricted to basolateral surfaces of polarized epithelial cells.polarized epithelial cells exhibit apical (lumenal) and basolateral (serosal) membrane domains that are separated by circumferential tight junctions. in such cells, enveloped viruses that mature by budding at cell surfaces are released at particular membrane domains. we have used a vaccinia virus recombinant to investigate the site of surface expression of the human immunodeficiency virus type 1 envelope glycoprotein in madin-darby canine kidney cells. cells were infected with the vaccinia virus ...19892536121
expression of mouse proopiomelanocortin in an insulinoma cell line. requirements for beta-endorphin processing.proopiomelanocortin (pomc) is a neuroendocrine precursor protein which is processed at paired basic amino acids in a tissue-specific manner. to study this phenomenon, a vaccinia virus recombinant, which directs the synthesis of mouse pomc (vv:mpomc) was constructed and used to infect epithelial (bsc-40) and endocrine (rin m5f) cell lines. bona fide mpomc was produced in both cell types and beta-endorphin immunoreactivity was secreted in a nonregulated manner from bsc-40 cells and in a regulated ...19892536749
virus-induced polyclonal cytotoxic t lymphocyte stimulation.infections with a variety of viruses (lymphocytic choriomeningitis (lcmv), murine cytomegalovirus, pichinde virus, vaccinia virus) stimulated c57bl/6 mice to generate allospecific ctl coincidental with the generation of virus-specific ctl. in c57bl/6 (h-2b) mice, lcmv-induced ctl with reactivity against cells from mice bearing gene products of the d, f, k, p, q, and s but not the b mhc loci. studies with congenic mouse strains indicated that the mhc loci coded for the target of the allospecific ...19892537363
recruitment to the cytoplasm of a cellular lamin-like protein from the nucleus during a poxvirus infection.monoclonal antibodies (mabs) directed against core proteins of rabbit poxvirus (rpv) have proven effective in the identification of host cell proteins such as rna polymerase ii (pol ii) that may play a role in the infectious process (d. k. morrison and r. w. moyer, 1986, cell 44, 587-596). in this article we describe a mab that has allowed the detection and characterization of a lamin-like protein derived from the nucleus of the infected cell, which like pol ii is recruited to the cytoplasm foll ...19892538026
the antiviral activity of 9-beta-d-arabinofuranosyladenine is enhanced by the 2',3'-dideoxyriboside, the 2',3'-didehydro-2',3'-dideoxyriboside and the 3'-azido-2',3'-dideoxyriboside of 2,6-diaminopurine.the 2',3'-dideoxyriboside (dddapr), 2',3'-didehydro-2',3'-dideoxyriboside (ddedapr) and 3'-azido-2',3'-dideoxyriboside (azdddapr) of 2,6-diaminopurine have been previously recognized as potent inhibitors of human immunodeficiency virus replication. these compounds are also potent inhibitors of adenosine deaminase and inhibit the deamination of 9-beta-d-arabinofuranosyladenine (araa). dddapr, ddedapr and azdddapr markedly potentiate the antiviral activity of araa against herpes simplex virus type ...19892538128
regulation of expression of herpes simplex virus (hsv) glycoprotein d in vaccinia recombinants affects their ability to protect from cutaneous hsv-2 disease.the effect of regulation of herpes simplex virus (hsv) type 1 glycoprotein d (gd-1) gene expression on hsv-specific immune response and protection from cutaneous hsv-2 disease was studied using vaccinia virus recombinants containing gd-1 under the control of early (vp176) or late (vp254) vaccinia virus promoters. expression of gd-1 in vp176-infected cells was first observed at 2 h after infection. it did not depend on viral dna replication. in vp254-infected cells, gd-1 was first observed at 24 ...19892538519
cervical papilloma virus treatment. 19892538555
synthesis, cellular location, and immunogenicity of bovine herpesvirus 1 glycoproteins gi and giii expressed by recombinant vaccinia virus.two of the major glycoproteins of bovine herpesvirus 1 (bhv-1) are gi, a polypeptide complex with apparent molecular weights of 130,000, 74,000, and 55,000, and giii (a 91,000-molecular-weight [91k] glycoprotein), which also exists as a 180k dimer. vaccinia virus (vac) recombinants were constructed which carry full-length gi (vac-i) or giii (vac-iii) genes. the genes for gi and giii were each placed under the control of the early vac 7.5k gene promoter and inserted within the vac gene for thymid ...19892539509
correlation between the antiviral activity of acyclic and carbocyclic adenosine analogues in murine l929 cells and their inhibitory effect on l929 cells s-adenosylhomocysteine hydrolase.for a series of acyclic and carbocyclic adenosine analogues, a close correlation was found between their inhibitory effect on murine l929 cell s-adenosylhomocysteine (adohcy) hydrolase and their inhibitory effects on the replication of vaccinia virus and vesicular stomatitis virus (r: 0.993 and 0.988, respectively). in terms of their increasing inhibitory action against both virus replication and adohcy hydrolase activity the compounds ranked as follows: (s)-9-(2,3-dihydroxypropyl)adenine less t ...19892539815
identification of the fusion peptide of primate immunodeficiency viruses.membrane fusion induced by the envelope glycoproteins of human and simian immunodeficiency viruses (hiv and sivmac) is a necessary step for the infection of cd4 cells and for the formation of syncytia after infection. identification of the region in these molecules that mediates the fusion events is important for understanding and possibly interfering with hiv/sivmac infection and pathogenesis. amino acid substitutions were made in the 15 nh2-terminal residues of the sivmac gp32 transmembrane gl ...19892541505
insertional mutagenesis of the vaccinia virus gene encoding a type i dna topoisomerase: evidence that the gene is essential for virus growth.vaccinia virus encodes a type i dna topoisomerase whose function in virus replication is not known. to determine whether topoisomerase is required for growth of vaccinia in cell culture, we attempted to isolate null mutations in the topoisomerase gene through insertional mutagenesis. plasmids containing mutant topoisomerase alleles were constructed by intragenic insertion of the escherichia coli gpt gene. recombinant viruses containing the gpt insertion were isolated by selection for growth in t ...19892541548
isolate- and group-specific immune responses to the envelope protein of human immunodeficiency virus induced by a live recombinant vaccinia virus in macaques.the immune responses produced by four macaques inoculated intradermally with a recombinant vaccinia virus that expresses the envelope gene of human immunodeficiency virus (hiv) were analyzed. antibody capable of immunoprecipitating the glycosylated envelope protein precursor gp160 was detected in all animals within 3 weeks after the primary intradermal vaccination. the level of antibody was increased following a booster inoculation, and the sera from three of the four animals were then capable o ...19892541747
scanning independent ribosomal initiation of the sendai virus y proteins in vitro and in vivo.the sendai virus p/c mrna contains five ribosomal initiation sites between positions 81 and 201 from the 5' end. one of these sites initiates in the p open reading frame (orf) (atg/104), whereas four initiate in the c orf (acg/81 and atgs/114, 183, 201), to give a nested set of c proteins (c', c, y1, y2). introduction of new atgs or physically breaking the mrna upstream of these natural sites was used in vitro to prevent ribosomal scanning downstream. the results suggest that a minority of the r ...19892542021
production of pro-opiomelanocortin (pomc) by a vaccinia virus transient expression system and in vitro processing of the expressed prohormone by pomc-converting enzyme.pro-opiomelanocortin (pomc) was expressed in cv-1 (green monkey kidney) cells using a vaccinia virus transient expression system [(1986) proc. natl. acad. sci. usa 83, 8122]. the system involved infection of cells with a recombinant vaccinia virus carrying the t7 rna polymerase gene and transfection with a plasmid containing the mouse pomc sequence flanked by the t7 rna polymerase promoter at its 5'-end and the t7 rna polymerase terminator at its 3'-end. assay of the medium from transfected cell ...19892542089
functional domains of vaccinia virus mrna capping enzyme. analysis by limited tryptic digestion.rna triphosphatase, rna guanylyltransferase, rna (guanine-7)-methyltransferase, and transcription termination factor activities are associated with the mrna capping enzyme from vaccinia virus. purified vaccinia capping enzyme is a 6.5 s protein containing two subunits of mr = 95,000 and mr = 31,000. although the rna guanylyltransferase domain has been localized to the large subunit by virtue of the formation of a mr = 95,000 covalent protein-gmp intermediate, the location of other functional dom ...19892542318
dna sequences that regulate expression of a vaccinia virus late gene (l65) and interact with a dna-binding protein from infected cells.to be efficiently expressed in vivo, the vaccinia virus late gene, l65, requires 5'-proximal cis-acting elements which bind a factor from infected cells. deletion mutagenesis and vaccinia virus helper-dependent transient expression procedures were used to demonstrate that two distinct late promoter elements direct transcription from two different start sites (proximal [+1] and distal [-92]). the -128 to -112 region was essential for l65 distal promoter function, while sequences between -59 and + ...19892542585
enhanced virus replication and inhibition of lymphocytic choriomeningitis virus disease in anti-gamma interferon-treated mice.the role of gamma interferon (ifn-gamma) induced during a viral infection in the ability of the host to acquire antiviral immunity was studied in mice. they were injected subcutaneously daily with an ammonium sulfate-precipitated sheep anti-ifn-gamma antibody preparation able to neutralize 10(4) u of ifn-gamma. specificity of the anti-ifn-gamma antiserum was demonstrated by absence of detectable activity against natural ifn-alpha and -beta. controls were treated with a similarly prepared normal ...19892542591
transcription inhibition site on the m protein of vesicular stomatitis virus located by marker rescue of mutant tso23(iii) with m-gene expression vectors.the matrix (m) protein of vesicular stomatitis virus serves as an endogenous inhibitor of viral transcription, a function missing or deficient in m proteins of temperature-sensitive (ts) mutants assigned to complementation group iii. previous studies with mutant tso23(iii) and vaccinia virus m-gene expression vectors revealed that the temperature-sensitive phenotype is due to a mutation leading to substitution of phenylalanine for leucine at amino acid iii, whereas loss of the major antigenic de ...19892542594
vaccinia dna topoisomerase i promotes illegitimate recombination in escherichia coli.vaccinia virus encapsidates a mr 32,000 type idna topoisomerase. although the vaccinia gene encoding the topoisomerase is essential for virus growth, the role of the enzyme in vivo remains unclear. in the present study, the physiologic consequences of vaccinia topoisomerase action have been examined in a heterologous system, escherichia coli. the vaccinia topoisomerase gene was inducibly expressed in an int-lambda lysogen bl21(de3) using a t7 rna polymerase-based transcription system. expression ...19892542933
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