involvement of p21ras in activation of extracellular signal-regulated kinase 2.many growth factors upon stimulation of their receptors induce the activity of extracellular signal-regulated kinases, erks, also known as map kinases. several of these growth factors also activate the ras proto-oncogene product, p21ras (ras), by stimulating the conversion of the inactive gdp-bound form of ras to the active gtp-bound form. we have shown that direct introduction of p21ras oncoprotein into cells in the absence of growth factors activates erks within five minutes, which indicates t ...19921608472
cotton rats previously immunized with a chimeric rsv fg glycoprotein develop enhanced pulmonary pathology when infected with rsv, a phenomenon not encountered following immunization with vaccinia--rsv recombinants or studies conducted in the 1960s, children previously immunized with a formalin-inactivated respiratory syncytial virus (rsv) vaccine (fi-rsv) developed a greater incidence and severity of pulmonary disease during subsequent natural rsv infection than did controls. it was previously shown that cotton rats immunized with fi-rsv or immunoaffinity-purified fusion (f) glycoprotein developed enhanced pulmonary histopathology following intranasal challenge with rsv. in the present studies, various fo ...19921609551
presence of cross-reactive antibody between human immunodeficiency virus (hiv) and platelet glycoproteins in hiv-related immune thrombocytopenic purpura.we previously reported the presence in platelet eluates of autoantibodies directed against epitopes of the platelet glycoprotein (gp)iib/iiia complex in acquired immunodeficiency syndrome (aids)-free human immunodeficiency virus (hiv)-infected patients with immunologic thrombocytopenic purpura (itp). we investigated whether hiv antibodies recognized platelet membrane antigens to determine whether the virus might be directly or indirectly responsible for the thrombocytopenia in this context. dire ...19921611083
processing pathways for presentation of cytosolic antigen to mhc class ii-restricted t cells.antigens presented to cd4+ t cells derive primarily from exogenous proteins that are processed into peptides capable of binding to class ii major histocompatibility complex (mhc) molecules in an endocytic compartment. in contrast, antigens presented to cd8+ t cells derive mostly from proteins processed in the cytosol, and peptide loading onto class i mhc molecules in an early exocytic compartment is dependent on a transporter for antigen presentation encoded in the class ii mhc region. endogenou ...19921614517
recombinant vaccine vector-induced protection of athymic, nude mice from influenza a virus infection. analysis of protective mechanisms.athymic, nude mice, which normally succumb to virus infection, can resolve infection with recombinant vaccinia virus (rvv) engineered to express il-2. we have demonstrated that interferon-gamma (ifn-gamma) produced by natural killer (nk) cells and other immunocytes in response to the virus-encoded interleukin-2 (il-2) is crucial to recovery. here, we extend this work to show that nude mice, when primed intravenously with rvv co-expressing both il-2 and an influenza virus haemagglutinin (ha) gene ...19921615287
processing and characterization of recombinant von willebrand factor expressed in different cell types using a vaccinia virus vector.the cloning of the cdna encoding von willebrand factor (vwf) has revealed that it is synthesized as a large precursor (pre-pro-vwf) molecule and it is now clear that the prosequence or vwagii is responsible for the intracellular multimerization of vwf. we have cloned the complete vwf cdna and expressed it using a recombinant vaccinia virus as vector. we have characterized the structure and function of the recombinant vwf (rvwf) secreted from five different cell types: baby hamster kidney (bhk), ...19921615470
antitumor activity and immune responses induced by a recombinant carcinoembryonic antigen-vaccinia virus vaccine.human carcinoembryonic antigen (cea) is a 180-kd glycoprotein expressed in human colorectal, gastric, pancreatic, breast, and non-small-cell lung carcinomas. previous studies have demonstrated enhanced immune responses to other antigens presented with vaccinia virus proteins via a recombinant vaccinia virus construct. in addition, we have developed a recombinant cea-vaccinia virus construct, designated rv(wr)-cea, and have demonstrated humoral anti-cea responses in mice after immunization with t ...19921619682
development of a live cell culture camelpox vaccine.a saudi isolate of camel orthopoxvirus was serially propagated on monolayers of camel kidney cell cultures. the attenuation of the 78th passage was tested in two susceptible camels. two other susceptible camels were inoculated with vaccinia virus four times propagated in camel kidney cell cultures. the four inoculated camels showed no postinoculation clinical symptoms and formed neutralizing antibodies against both the camel orthopox and vaccinia viruses. no postchallenge clinical symptoms were ...19921621417
immunosuppression by lymphocytic choriomeningitis virus infection: competent effector t and b cells but impaired antigen presentation.lymphocytic choriomeningitis virus (lcmv) may cause a severe immunosuppression in mice. its pathogenesis is apparently dependent on lcmv-specific cd8 effector t cells that mediate the destruction of virus-infected cells which are normally essentially involved in immune responses. evaluation of various lcmv isolates in this study established a general correlation between their tropism for lymphohemopoietic cells and immunosuppression. when immune responses were assessed as the capacity of mice to ...19921623925
chemotherapeutic prevention of complications caused by vaccinia virus-vectored immunogen.vaccinia virus strains and constructs differ greatly in the number of pfus required to produce tail lesions in the vaccinia virus mouse model. the pathogenesis of lesion formation appeared to involve virus spread from an initial focus in specific cells surrounding hair follicles to other concentrated areas of the dermis and finally, at the time of lesion development, to the epidermis. antivirals that suppressed tail lesions, to a greater or lesser degree, included ara a, ribavirin, rifampicin, a ...19921626883
interleukin-2, a pro-autoimmune lymphokine that interferes with post-deletional tolerance.various complementary mechanisms arranged in a fail-safe hierarchy impede the immune system from launching auto-aggressive attacks, namely intrathymic or post-thymic clonal deletion, anergy, and immunosuppression. both epidemiological and clinical evidence demonstrates that interleukin-2 (il-2) may exert a pro-autoimmune effect. thus, il-2 reverses immunological tolerance in determined in vitro or in vivo circumstances, is produced at abnormally high levels in certain autoimmune diseases, and in ...19921627788
influenza virus hemagglutinin with multibasic cleavage site is activated by furin, a subtilisin-like endoprotease.many viruses have membrane glycoproteins that are activated at cleavage sites containing multiple arginine and lysine residues by cellular proteases so far not identified. the proteases responsible for cleavage of the hemagglutinin of fowl plague virus, a prototype of these glycoproteins, has now been isolated from madin-darby bovine kidney cells. the enzyme has a mol. wt of 85,000, a ph optimum ranging from 6.5 to 7.5, is calcium dependent and recognizes the consensus sequence r-x-k/r-r at the ...19921628614
mutational analysis of the core, spacer, and initiator regions of vaccinia virus intermediate-class promoters.activation of vaccinia virus late gene transcription is dependent on dna replication and the expression of three genes: a1l, a2l, and g8r (j. g. keck, c. j. baldick, jr., and b. moss, cell 61:801-809, 1990). to fully characterize the promoter elements of these trans-activator genes, we prepared more than 140 plasmid vectors containing natural and mutated dna segments ligated to the escherichia coli lacz or chloramphenicol acetyltransferase reporter gene. expression of the reporter genes occurred ...19921629951
spike protein-nucleocapsid interactions drive the budding of alphaviruses.semliki forest virus (sfv) particles are released from infected cells by budding of nucleocapsids through plasma membrane regions that are modified by virus spike proteins. the budding process was studied with recombinant sfv genomes which lacked the nucleocapsid protein gene or, alternatively, the spike genes. no subviral particles were released from cells which expressed only the nucleocapsid protein or the spike proteins. virus release was found to be strictly dependent on the coexpression of ...19921629953
expression of wild-type and mutant p53 proteins by recombinant vaccinia facilitate the purification of wild type p53 protein, we established a recombinant p53 vaccinia viral expression system. using this efficient eukaryotic expression vector, we found that the expressed p53 proteins retained their specific structural characteristics. a comparison between wild type and mutant p53 proteins showed the conservation of the typical subcellular localization and the expression of specific antigenic determinants. furthermore, wild type p53 exhibited a typical binding wit ...19921630914
beta 2-microglobulin-, cd8+ t-cell-deficient mice survive inoculation with high doses of vaccinia virus and exhibit altered igg responses.transgenic mice lacking an intact beta 2-microglobulin (beta 2m) gene fail to express major histocompatibility complex (mhc) class i proteins on the cell surface and, as a result, are virtually devoid of cd4- cd8+ lymphocytes. these animals provide a unique model system for directly assessing the role of cd8+ lymphocytes in the modulation of viral infection in vivo. beta 2m- cd8- mice and their normal littermates were inoculated at the base of the tail with the wr strain of vaccinia virus and mo ...19921631092
bovine respiratory syncytial virus nucleocapsid protein: mrna sequence analysis and expression from recombinant vaccinia virus vectors.the nucleotide sequence of the mrna encoding the nucleocapsid (n) protein of bovine respiratory syncytial (brs) virus, strain 391-2, was determined. recombinant vectors containing a cdna of the complete n gene were constructed, and expression of the n protein in eukaryotic cells was demonstrated using two different vector systems. the brs virus n mrna was 1197 nucleotides in length, exclusive of poly(a), and had a single major open reading frame that encoded a polypeptide of 391 amino acids with ...19921634882
synthesis and secretion of a functional antibody in a vaccinia virus expression system.a humanized rat monoclonal antibody (campath 1h) has been expressed in hela cells using recombinant vaccinia viruses. heavy and light chain recombinant viruses were constructed separately and when grown independently produced proteins of the expected molecular weights. expressed heavy chain was entirely intracellular but light chain was mainly excreted and processed. when cells were infected at high multiplicity with both heavy and light chain recombinants a proportion of the heavy chain was the ...19921635559
acceleration of tail pinch-induced feeding in rats by analgesic effect of neurotropin.mechanisms of tail pinch-induced feeding and effects of neurotropin (nsp), an extract from the inflamed skin of rabbit inoculated with vaccinia virus, on behavioral responses were investigated in rats. treatment of a 5-min tail pinch (tail pinch i) induced feeding response. an intensified 15-min tail pinch (tail pinch ii) provoked emotional reactions besides feeding behavior. the rate of food intake (food intake/tail pinch duration) during tail pinch ii was less than that at tail pinch i. intrap ...19921641425
the vaccinia virus k2l gene encodes a serine protease inhibitor which inhibits cell-cell certain circumstances, cells infected with vaccinia virus (vv) undergo fusion, but this does not occur in tissue cultures infected with wild-type vv. the vv genome includes three genes (b24r, b13r, and k2l) encoding polypeptides that are structurally related to members of the plasma serine proteases inhibitor (spi) superfamily. in this study, we demonstrate by deleting these genes singly or in combination that the k2l gene encoding spi-3, but not the b24r or b13r genes encoding spi-1 and spi- ...19921641985
active specific adjuvant immunotherapy with vaccinia melanoma oncolysate.vaccinia melanoma oncolysate is an investigative agent for active specific adjuvant immunotherapy. viral oncolysate work in animals has led to application of this treatment in humans. success of initial trials in treatment of melanoma has led to a phase iii randomized, prospective, double-blind, multi-institutional trial, which is currently under way.19921642396
prospects for gene therapy and lymphokine therapy for metastatic melanoma.conventional treatment of cancer, especially for patients with metastatic melanoma tumor, is often ineffective. immunotherapy and recently introduced gene therapy have revolutionized the treatments of patients with metastatic melanoma tumor. use of biological response modifiers, such as interleukins and interferons, have been found to enhance therapeutic benefits to patients with malignant melanoma. initial studies with a high-dose interleukin-2 (il-2) therapy have proved effective in patients w ...19921642399
cloning, sequencing, expression, and gq-independent activation of phospholipase c-beta 2.cdnas corresponding to a previously uncharacterized phospholipase c were isolated from an hl-60 cell cdna library. the cdnas encodes a putative polypeptide of 1181 amino acids with a calculated molecular mass of 133,700 daltons. comparison of the amino acid sequence of the predicted protein with those of five mammalian phospholipase c isoforms (plc-beta 1, plc-gamma 1, plc-gamma 2, plc-delta 1, and plc-delta 2) revealed that the new enzyme is most closely related to plc-beta 1 with an overall am ...19921644792
[5-variable genome sequence of the livp vaccinia virus. a possible role for short direct repeats in the formation of deletions].hindiii-o/n dna fragments of vaccinia virus (vv) of the livp strain were mapped using thirteen restriction endonucleases. nucleotide sequences of the hindiii-o fragment (1530 bp) as well as of a site of the hindiii-n genome fragment 353 bp in size were determined. comparison of restriction maps and nucleotide sequences of vv strains (wr and livp) demonstrated that dna of vv livp contained % deletions and 2 insertions. "reliable" short direct repeats were localized and their possible role in form ...19911645323
site-specific interaction of vaccinia virus topoisomerase i with duplex dna. minimal dna substrate for strand cleavage in vitro.purified vaccinia virus dna topoisomerase i forms a cleavable complex with duplex dna at a conserved sequence element 5'(c/t)ccttdecreases in the incised dna strand. dnase i footprint studies show that vaccinia topoisomerase protects the region around the site of covalent adduct formation from nuclease digestion. on the cleaved dna strand, the protected region extends from +13 to -13 (+1 being the site of cleavage). on the noncleaved strand, the protected region extends from +13 to -9. similar n ...19911645733
recombinant vaccinia virus expression of the bovine leukaemia virus envelope gene and protection of immunized sheep against infection.the bovine leukaemia virus (blv) envelope gene encoding extracellular glycoprotein gp51 and transmembrane glycoprotein gp30 was cloned into the ha locus of vaccinia virus (copenhagen strain), downstream of the vaccinia virus early-late promoter, h6, or a triple promoter element consisting of the promoter for the vaccinia virus h6 gene, the promoter for the cowpox virus a-type inclusion (ati) gene and the promoter for the vaccinia virus ha gene. inoculation of rabbits or sheep with the recombinan ...19911645899
expression and cellular localisation of porcine transmissible gastroenteritis virus n and m proteins by recombinant vaccinia viruses.porcine transmissible gastroenteritis virus (tgev) nucleoprotein and integral membrane protein genes were cloned into the vaccinia virus insertion vector, pgs20, in the correct orientation for expression under the control of the vaccinia p7.5k promoter. recombinant vaccinia viruses were generated by in vivo homologous recombination of the insertion vector with the wr strain of vaccinia virus. nucleoprotein (n) expressed by both recombinant vaccinia virus and tgev had a relative molecular mass (m ...19911645905
an influenza haemagglutinin-specific igg enhances class i mhc-restricted ctl killing in vitro.lungs of h-2k mice co-inoculated with type a/wsn influenza virus+detective interfering wsn virus contain haemagglutinin (ha)-specific igg which have three different activities. these have been purified by adsorbtion and elution using different forms of ha. the first igg recognizes ha in a form present on h-2k cells infected with a vaccinia virus recombinant expressing the wsn ha gene (vaccinia-ha virus), but not on virus particles, and enhances class i major histocompatibility complex (mhc)-rest ...19911646161
high level transient expression of the murine coronavirus haemagglutinin-esterase.we have expressed the murine coronavirus haemagglutinin-esterase protein in a vaccinia virus/t7 rna polymerase system. the levels of expression observed are significantly higher than those found in virus-infected cells. the expressed protein has both receptor-destroying (esterase) and receptor-binding (haemadsorption) activities. the use of this system will greatly facilitate analysis of the structure-function relationships of this protein.19911646274
immunogenicity in mice of varicella-zoster virus glycoprotein i expressed by a vaccinia virus-varicella-zoster virus recombinant.several vaccinia virus (vv)-varicella-zoster virus (vzv) recombinants expressing glycoprotein i (gpi) of vzv were isolated from the prague strain of vv. one of these, v46, was inoculated intraperitoneally into mice. groups of mice were bled 4 and 8 weeks later and their sera were examined for anti-vzv and anti-vv antibodies by elisa. at 4 weeks, all mice inoculated with the three largest virus doses (10(7), 10(6) and 10(5) p.f.u.), and at 8 weeks all mice inoculated with the four highest virus d ...19911646285
construction of a pigeonpox virus recombinant: expression of the newcastle disease virus (ndv) fusion glycoprotein and protection of chickens against ndv challenge.a pigeonpox transfer plasmid was constructed by cloning a 2.5 kb dna fragment containing the viral thymidine kinase (tk) gene in the psp65 plasmid. the vaccinia virus p11k promoter followed by the ndv fusion (f) gene was inserted in the tk gene. the f gene was transferred to the viral genome by homologous recombination in pigeonpox virus infected cef cells, transfected with the recombinant plasmid. recombinant viruses were selected with budr and screened for their ability to induce fusion betwee ...19911646592
the fusion and hemagglutinin-neuraminidase glycoproteins of human parainfluenza virus 3 are both required for fusion.recombinant vaccinia viruses, vf and vhn, expressing the fusion (f) and hemagglutinin-neuraminidase (hn) glycoproteins of human parainfluenza virus 3 (hpiv3) were constructed. infection of hela t4 cells with vf and vhn led to the synthesis of glycoproteins, with the correct apparent molecular weights, that were recognized by monoclonal antibodies specific for hpiv3f and hn. the hn glycoprotein was present on the surface of cells infected with vhn and these cells demonstrated both hemadsorbing an ...19911647076
a temperature-sensitive lesion in the small subunit of the vaccinia virus-encoded mrna capping enzyme causes a defect in viral telomere resolution.using pulsed-field gel electrophoresis, we demonstrated that the temperature-sensitive (ts) conditional lethal mutant ts9383 is, at the nonpermissive temperature, defective in the resolution of concatemeric replicative intermediate dna to linear 185-kb monomeric dna genomes. the resolution defect was shown to be the result of a partial failure of the mutant virus to convert the replicated form of the viral telomere to hairpin termini. in contrast to other mutants of this phenotype, pulse-labelin ...19911649315
identification and dna sequence of the large subunit of the capping enzyme from shope fibroma virus.a 3.6-kb region of the shope fibroma virus (sfv) bamhi d fragment located in the central region of the viral genome was sequenced. three open reading frames (orfs) were identified, d3r, d4l, and d5r. each of these orfs have a counterpart organized identically within the hindiii fragment d of the vaccinia virus genome (d1r, d2l, and d3r). homology scores and assays of viral cores indicate that sfv d3r encodes the large subunit of the sfv mrna capping enzyme.19911649507
vaccinia virus capping enzyme is a transcription initiation has previously been demonstrated that vaccinia virus capping enzyme is involved both in the formation of a 5' cap structure and in termination of early transcription. here we show that capping enzyme has an additional activity which is required for transcription of intermediate genes. vitf-a and vitf-b have been defined as two activities which together with rna polymerase are necessary and sufficient to transcribe intermediate genes in vitro. vitf-a and the viral capping enzyme are shown to c ...19911651230
murine infection by vesicular stomatitis virus: initial characterization of the h-2d system.balb/c mice and congenic h-2ld-deficient balb/c-h-2dm2 (dm2) mice were experimentally infected intranasally with isolates of vesicular stomatitis virus (vsv). the survival of infected hosts, viral replication in lungs and brains, and histopathologic in the two mouse strains were compared. in both strains of mice, mortality occurred during the period 7 to 10 days postinfection. however, dm2 mice were relatively resistant to lethal infections. viral replication occurred at low levels in the lungs ...19911651414
the hepatitis a virus polyprotein expressed by a recombinant vaccinia virus undergoes proteolytic processing and assembly into viruslike particles.hepatitis a virus (hav) contains a single-stranded, plus-sense rna genome with a single long open reading frame encoding a polyprotein of approximately 250 kda. viral structural proteins are generated by posttranslational proteolytic processing of this polyprotein. we constructed recombinant vaccinia viruses which expressed the hav polyprotein (rv-orf) and the p1 structural region (rv-p1). rv-orf-infected cell lysates demonstrated that the polyprotein was cleaved into immunoreactive 29- and 33-k ...19911651421
transactivation by herpes simplex virus proteins icp4 and icp0 in vaccinia virus infected cells.vaccinia virus recombinants containing the sequences from herpes simplex virus type 1 (hsv-1) encoding the immediate early (ie)(alpha) proteins icp4 and icp0, under the control of a mutated vaccinia virus 11k late promoter, were constructed. a cdna copy of the gene encoding icpo and an icp4-encoding genomic segment were each inserted into the vaccinia virus genome at the thymidine kinase (tk) locus by homologous recombination. steady-state analyses revealed that rnas homologous to the ie-0 and i ...19911651605
metabolic activation of 4-ipomeanol by complementary dna-expressed human cytochromes p-450: evidence for species-specific metabolism.4-ipomeanol is a pulmonary toxin in cattle and rodents that is metabolically activated by cytochromes p-450 (p-450s). p-450-mediated activation of 4-ipomeanol to dna binding metabolites was evaluated using a vaccinia virus complementary dna expression system and an in situ dna-binding assay. twelve human p-450s and two rodent p-450s were expressed in human hepatoma hep g2 cells and examined for their abilities to metabolically activate this toxin. three forms, designated cyp1a2, cyp3a3, and cyp3 ...19911651809
protective immunity against bovine leukaemia virus (blv) induced in carrier sheep by inoculation with a vaccinia virus-blv env recombinant: association with cell-mediated immunity.the effects of vaccination of sheep with a recombinant vaccinia virus (rvv) expressing the bovine leukaemia virus (blv) envelope glycoprotein (gp60) were studied by determining blv titres in peripheral blood leukocytes after vaccination and challenge. the proliferation of blv was suppressed markedly, not only when rvv was inoculated prior to challenge with blv, but also when it was inoculated after challenge. these results indicate that vaccination with rvv induces protective immunity that can s ...19911651982
virus permeability of protective gloves used in medical practice.from a large number of different kinds of protective gloves currently on the market, 19 were selected for virus permeability testing using a special model. most of the gloves tested offered poor mechanical protection against penetration of adenovirus and poliovirus, while vaccinia virus was found to traverse the gloves less freely.19911652967
outer capsid glycoprotein vp7 is recognized by cross-reactive, rotavirus-specific, cytotoxic t lymphocytes.cytotoxic t lymphocytes (ctls) generated in mice orally inoculated with rotaviruses lyse target cells infected with different rotavirus serotypes (cross-reactive ctls). using vaccinia virus recombinants expressing individual rotavirus proteins from two different rotavirus serotypes, we found that cross-reactive ctls recognize target cells expressing outer capsid protein vp7 better than those expressing outer capsid protein vp4 or inner capsid protein vp6. these findings may be relevant to vaccin ...19911653488
a recombinant vaccinia virus expressing hepatitis a virus structural polypeptides: characterization and demonstration of protective immunogenicity.a recombinant vaccinia virus containing most of the p1 region of hepatitis a virus (hav) was constructed. cell lysates of cultures infected with the virus contained hav proteins detectable by radioimmunoassay. western blot analysis revealed the presence of a single protein of mr 60k to 62k, bearing epitopes from structural polypeptides vp4, -3 and -2, and the n terminus of vp1. the size of the protein suggests that at least some of the vaccinia virus thymidine kinase is also expressed. inoculati ...19911654376
localization of the non-structural protein ns3 in bluetongue virus-infected cells.the localization of the blue tongue virus (btv) non-structural proteins ns3 and ns3a has been identified using immunoelectron microscopical techniques. ns3 and ns3a have been observed in the plasma membrane of btv- and recombinant vaccinia virus (expressing ns3)-infected cells. the ns3 protein was associated with areas of membrane perturbation. there was a good correlation between the presence of ns3 and ns3a and btv release. the ns3 protein was associated with membrane fragments and the inabili ...19911654377
increased expression in vivo and in vitro of foreign genes directed by a-type inclusion body hybrid promoters in recombinant vaccinia viruses.we constructed a-type inclusion body (ati) hybrid promoters, that is, late ati promoters followed by tandemly repeated early regions of the promoter for the 7.5-kda protein (the 7.5-kda promoter). the repetition of the whole early promoter sequence of the 7.5-kda gene, including the upstream consensus sequence and initiation region, efficiently increased the early expression of the bacterial chloramphenicol acetyltransferase gene in recombinant vaccinia virus. recombinant vaccinia virus could ex ...19911654453
neutralizing antibodies induced by recombinant vaccinia virus expressing varicella-zoster virus gpiv.monoclonal antibodies generated against varicella-zoster virus (vzv) glycoprotein i (gpi) also recognize vzv gpiv (a. vafai, z. wroblewska, r. mahalingam, g. cabirac, m. wellish, m. cisco, and d. gilden, j. virol. 62:2544-2551, 1988). to determine whether the virus-neutralizing activity of these antibodies belongs to gpi, gpiv, or both, the open reading frame encoding gpiv was inserted into the vaccinia virus genome. immunoprecipitation of recombinant vaccinia virus-infected cells with anti-gpiv ...19911654454
the purified 14-kilodalton envelope protein of vaccinia virus produced in escherichia coli induces virus immunity in animals.vaccinia virus (vv) was successfully used as a live vaccine to eradicate smallpox, but the nature of viral proteins involved in eliciting viral immunity has not yet been identified. a potential candidate is a 14-kda vv envelope protein that is involved in virus penetration at the level of virus-cell fusion, in cell-cell fusion late in infection, and in virus dissemination. the 14-kda envelope protein has been produced in escherichia coli, with properties similar to those of the native protein fo ...19911654459
analysis of the specificity and mechanism of transcriptional activation of the human hsp70 gene during infection by dna viruses.we have examined the transcriptional regulation of the 70-kda (70k) heat shock gene family following infection of human and monkey cells with four different dna viruses: adenovirus type 5 (ad5), herpes simplex virus type 1 (hsv-1), simian virus 40, and vaccinia virus. our results indicate that induction of these genes is not a general response to the stress of viral infection but is instead a highly specific response, both with regard to the inducing virus and with regard to the target gene. of ...19911656064
structure and genetic variability of envelope glycoproteins of two antigenic variants of caprine arthritis-encephalitis define the structure of the caprine arthritis-encephalitis virus (caev) env gene and characterize genetic changes which occur during antigenic variation, we sequenced the env genes of caev-63 and caev-co, two antigenic variants of caev defined by serum neutralization. the deduced primary translation product of the caev env gene consists of a 60- to 80-amino-acid signal peptide followed by an amino-terminal surface protein (su) and a carboxy-terminal transmembrane protein (tm) separated by an ...19911656067
expression of vaccinia recombinant hpv 16 l1 and l2 orf proteins in epithelial cells is sufficient for assembly of hpv virion-like particles.a recombinant vaccinia virus termed plc201vv was designed to coexpress the l1 and l2 late genes of human papillomavirus type 16 (hpv16). synthesis of the l1 and l2 proteins occurred in cells infected with plc201vv, and 40-nm virus-like particles with a density of 1.31 g/ml were produced in the nuclei of cells synthesizing both l1 and l2, but not in cells synthesizing either protein alone. virus-like particles were partially purified from infected cells by sucrose gradient sedimentation and shown ...19911656586
isolation and enzymatic characterization of protein lambda 2, the reovirus guanylyltransferase.protein lambda 2 of reovirus serotype 3 has been purified to homogeneity from extracts of cells infected with hybrid vaccinia virus strain wr into whose tk gene of the reovirus l2 genome segment under the control of the cpv ati protein gene promoter had been inserted. protein lambda 2 is formed in large amounts (final purification factor about 180) as a monomer that shows no tendency to pentamerize into the reovirus core projections/spikes. isolated protein lambda 2 is reversibly guanylylated by ...19911656591
production of 22 nm hbsag particles by human lymphocytes infected with a recombinant vaccinia virus containing the coding sequence for hepatitis b virus surface examine the possible role of lymphocytes in the course of hepatitis b virus infection, we studied peripheral blood lymphocytes and epstein-barr virus transformed b-cells for their capability to produce hepatitis b virus gene products. infection of these cells with a recombinant vaccinia virus containing the hepatitis b virus surface antigen resulted in the production and secretion of hepatitis b virus surface antigen shortly after infection reaching a peak after three days. when the supernata ...19911656954
vaccinia virus encodes an active thymidylate kinase that complements a cdc8 mutant of saccharomyces cerevisiae.a vaccinia virus open reading frame (orf) previously predicted to encode thymidylate kinase (tmpk) is shown to encode an active enzyme. a copy of the orf, generated by polymerase chain reaction, was cloned into an escherichia coli inducible expression vector. cell extracts of e. coli expressing the vaccinia gene contained high levels of tmpk activity, whereas extracts of cells without the tmpk gene did not. the vaccinia orf expressed from a yeast vector complemented a saccharomyces cerevisiae cd ...19911657913
structural analysis of unstable intermediate and stable forms of recombinant fowlpox virus.the stability and structure of the products of recombination in a fowlpox virus (fpv) system using the thymidine kinase (tk) gene as the insertion site were examined. a 4.6 kb chimeric dna fragment from the puv1 expression vector, containing the bacterial lacz gene and the vaccinia virus p7.5 promoter, was ligated into the xbai site of the fpv tk gene. the resulting vector, pftklaczb, was transfected into chicken embryo fibroblast cultures infected with fpv at an m.o.i. of 0.1. recombinants were ...19911658207
role of de novo protein synthesis in target cells recognized by cytotoxic t lymphocytes specific for vesicular stomatitis virus.the requirements for viral and host protein synthesis in the generation of target antigens for cytotoxic t lymphocytes (ctl) was evaluated by using vesicular stomatitis virus (vsv) inactivated by uv irradiation (uv-vsv). el4 target cells incubated with uv-vsv were recognized and lysed by anti-vsv ctl, indicating that de novo synthesis of viral proteins was not required for the generation of antigens recognized by antiviral ctl. anti-vsv ctl from h-2b mice primarily recognize determinants derived ...19911658379
recombination mediated by vaccinia virus dna topoisomerase i in escherichia coli is sequence specific.specialized type i topoisomerases catalyze dna strand transfer during site-specific recombination in prokaryotes and fungi. as a rule, the site specificity of these systems is determined by the dna binding and cleavage preference of the topoisomerase per se. the mr 32,000 topoisomerase i encoded by vaccinia virus (a member of the eukaryotic family of "general" type i enzymes) is also selective in its interaction with dna; binding and cleavage occur in vitro at a pentameric motif 5'-(c or t)cctt ...19911658796
high expression of human cytomegalovirus (hcmv)-gb protein in cells infected with a vaccinia-gb recombinant: the importance of the gb protein in hcmv immunity.the human cytomegalovirus (hcmv), towne strain, glycoprotein b (gb) gene was cloned into a vaccinia vector (copenhagen strain) under the control of the h6 early and late vaccinia promoters (vac-gb recombinant). the gb protein was expressed in a high percentage of the vac-gb-infected cells throughout the virus replication cycle. cytosine-arabinoside (ara-c) did not influence the expression of the gb protein early after infection (5 h), but did inhibit it later in viral replication (7-29 h). the v ...19911659051
effects of protein kinase c inhibitors on viral entry and infectivity.the protein kinase c inhibitor h-7 (2-20 microm) inhibited dose-dependently the infectivity of the vesicular stomatitis virus on cultured human fibroblasts. electron microscopy showed that h-7 inhibited the viral entry. h-7 also inhibited the infectivity of four other enveloped viruses, herpes simplex i, turkey herpes, vaccinia and sindbis. similar results were obtained using staurosporine (2.5 nm), tamoxifen (40 microm), phloretin (140 microm), or w-7 (40 microm). however, the infectivity of no ...19911659999
sequence and analysis of a portion of the genomes of shope fibroma virus and malignant rabbit fibroma virus that is important for viral replication in lymphocytes.the 10.7-kb bamhi "c" restriction fragment of malignant rabbit fibroma virus (mv) contains genes that are important for its immunosuppressive activity. when this fragment is transferred to a related avirulent leporipoxvirus, shope fibroma virus (sfv), recombinant viruses show clinical features characteristic of mv: they replicate in lymphocytes and alter immune function in vitro, induce disseminated tumors in recipient rabbits, and are immunosuppressive in vivo. the 10.7-kb bamhi "c" restriction ...19911660196
identification of the nuclear localization signal of human papillomavirus type 16 l1 protein.human papillomavirus type 16(hpv16) l1 and l2 capsid proteins can be detected only in the nucleus of infected cells. for other nuclear proteins, specific sequences of basic amino acids(aa) termed nuclear localization signals (nls) direct the protein from the cytoplasm to the nucleus. we used a series of deletion and substitution mutations of the hpv16 l1 protein, produced by recombinant vaccinia virus (rvv), to identify nls within hpv16 l1 and showed that hpv16 l1 contains two nls sequences, eac ...19911660197
the hygromycin-resistance-encoding gene as a selection marker for vaccinia virus recombinants.hygromycin b (hy), an inhibitor of rna translation, was shown to block the replication of vaccinia virus (vv) in cultured cell lines. insertion of the escherichia coli hy resistance-encoding gene (hph) into the vv genome under control of early or late synthetic vv promoters could overcome inhibition of viral replication. when hph was inserted into vv in tandem with the human papillomavirus type 16 (hpv16) l1 open reading frame, hph recombinant viruses could be selected which expressed hpv16 l1.19911660832
enhancement of the vaccinia virus/phage t7 rna polymerase expression system using encephalomyocarditis virus 5'-untranslated region sequences.a recombinant vaccinia virus producing the bacteriophage t7 rna polymerase was used to express foreign genes in eukaryotic cells. translation efficiency in this expression system was enhanced significantly by employing the encephalomyocarditis virus (emcv) 5'-untranslated region (utr) which confers cap-independent translation by directing internal initiation of translation. the enhancement was accomplished by fusing open reading frames (orfs) to the n terminus of the emcv polyprotein coding regi ...19911660838
biologically active recombinant prothrombin and antithrombin iii expressed in a human hepatoma/vaccinia virus system.several systems have been devised that are based on viral promoters suitable for gene expression in eukaryotic cells. one such system, vaccinia virus, has been successfully used to express a variety of heterologous proteins following the construction of a recombinant virus. indeed, because of the ability of vaccinia virus to infect a wide range of host cells, the expression system can be custom-designed so that a cell line can be instrumental in ensuring the correct processing of the recombinant ...19911662049
[cloning, sequencing and translation analysis of the vaccinia virus livp hindiii n genome fragment].the sequence of vaccinia virus (vv) livp hindiii n dna fragment has been determined to be 2215 b.p. three open reading frames designated ln1, n1 and no1 and coding polypeptides with the calculated molecular masses (32.5 kda, 21.8 kda and 47.8 kda) were located. mrnas selected by hybridization with the vv hindiii n were translated in rabbit reticulocyte lysate. proteins of genes for host range and resistance to alpha-amanitin corresponding to 29 and 47 kda were detected. two forms of polypeptides ...19911663471
live vaccinia virus recombinants expressing herpes simplex virus genes.vaccinia virus recombinants expressing antigens from herpes simplex virus (hsv) have been tested as potential live virus vaccines for prevention of hsv infection. we describe three vaccinia virus/hsv recombinants. the first expresses the hsv-1 glycoprotein d (vaccinia/gd), the second expresses the hsv-1 glycoprotein b (vaccinia/gb), and the third expresses both the hsv-1 glycoprotein d and the influenza a hemagglutinin (vaccinia/hsvgd/influenza). mice immunized with vaccinia/gd or vaccinia/gb de ...19911664124
immune responses to herpes simplex virus in guinea pigs (footpad model) and mice immunized with vaccinia virus recombinants containing herpes simplex virus glycoprotein d.vaccinia virus recombinants containing the herpes simplex virus (hsv) gene for glycoprotein d type 1 (gd-1) under control of an early (vp176) or late (vp254) vaccinia virus promoter or for hsv glycoprotein type 2 (gd-2) under control of the early promoter (vp221) were studied for their ability to induce protective immunity to hsv-2 in the guinea pig model of cutaneous recurrent disease and the mouse model of fatal disease. titers of hsv-specific neutralizing antibody were similar in the two grou ...19911664130
expression of mammalian cytochrome p450 using vaccinia virus. 19911664484
in vitro virucidal activity of selected anthraquinones and anthraquinone derivatives.anthraquinones and anthraquinone derivatives were characterized for their antiviral and virucidal activities against viruses representing several taxonomic groups. one of these compounds, hypericin, had activity against vesicular stomatitis virus, herpes simplex virus types 1 and 2, parainfluenza virus, and vaccinia virus (from 0.5 to 3.8 log10 reductions in infectivity) at concentrations of less than 1 microgram/ml as determined by a direct pre-infection incubation assay. human rhinovirus was n ...19911665961
[search for antimetabolites among 5-trimethylsilyluracil nucleosides and their nonglycoside analogs].the reaction of 2'-deoxy-5-trimethylsilyl(tms)uridine with methanesulfonyl chloride led to the corresponding 3',5'-di-o-mesyl derivative, which was treated with lithium toluylate in dmf to give 2,3'-anhydro-1-(2-deoxy-5-o-p-toluyl-beta-d-xylofurano- syl)-5-tms-uracil. under these conditions 1-(2,3-dideoxy-5-o-p-toluyl-alpha-d- glycero-pent-2-enofuranosyl)-5-tms-uracil was obtained from 1-(2-deoxy-alpha-d-ribofuranosyl)-5-tms-uracil. interaction of 2,3'-anhydronucleoside with lin3 in dmf and succ ...19911667356
a preliminary study on the immunogenicity in rabbits and in human volunteers of a recombinant vaccinia virus expressing epstein-barr virus membrane antigen. 19911667485
poly(a) polymerase and a dissociable polyadenylation stimulatory factor encoded by vaccinia virus.mrna made in eukaryotic cells typically has a 3' poly(a) tail that is added posttranscriptionally. to investigate mechanisms by which 3' poly(a) is formed, we identified the genes for the two vaccina virus-encoded polypeptides, vp55 and vp39. primer-dependent polyadenylation activity was associated exclusively with purified vp55-vp39 heterodimer, which, although stable to column chromatography and glycerol gradient sedimentation, was readily dissociated by antibody to an n-terminal peptide of vp ...19911670500
safety of and immunological response to a recombinant vaccinia virus vaccine expressing hiv envelope a randomised phase i trial of a recombinant vaccina virus vaccine expressing the gp160 envelope gene of the human immunodeficiency virus (hivac-1e) 35 healthy, hiv-seronegative males, 31 of whom had a history of smallpox immunisation and 4 of whom were vaccinia naive, were vaccinated and then boosted 8 weeks later with hivac-1e or standard ny strain vaccinia virus. the frequency, duration, and titre of virus isolation from the vaccination site and occurrence of local side-effects were similar ...19911671940
safety of recombinant vaccinia vaccines. 19911672987
vaccinia from recombinant virus expressing hiv genes. 19911673182
safety of recombinant vaccinia vaccines. 19911673183
antibody response to the negative regulatory factor (nef) in experimentally infected macaques: correlation with viremia, disease progression, and seroconversion to structural viral proteins.the antibody response to structural and regulatory viral proteins was studied in 14 rhesus (macaca mulatta) and 6 cynomolgus (macaca fascicularis) macaques experimentally infected with hiv-2 or sivmac. to investigate the humoral antibody response to the negative regulatory factor (nef), the recombinant protein was expressed to high levels with recombinant vaccinia virus (vv). nef-specific antibodies were detected in 14 of 20 infected macaques (70%). in sera of all infected monkeys antibodies dir ...19911675823
accidental infection of laboratory worker with recombinant vaccinia virus. 19911678128
effect of a glucosidase inhibitor on the bioactivity and immunoreactivity of human immunodeficiency virus type 1 envelope glycoprotein.apparently conflicting results have been reported regarding the role of env glycoprotein glycans in human immunodeficiency virus type 1 (hiv-1) infectivity and cytopathogenicity. whereas we have shown that enzymic removal of carbohydrates from mature envelope glycoproteins has only limited effect on the ability of hiv-1 to bind to cd4 and to infect target cells, sugar analogues that interfere with the glycosylation process of the nascent molecule markedly reduce virus infectivity. here we have i ...19911678778
anti-hiv cellular immunotherapy in aids. 19911679492
a rapid method for screening vaccinia virus recombinants.a rapid and small-scale method for screening vaccinia virus recombinants employing micrococcal nuclease is described. this protocol utilizes the differential sensitivity of cellular and viral dna to the nuclease, which can be selectively activated by addition of ca2+ and inactivated by elimination of ca2+. two to five micrograms of viral dna can be obtained from one infected l cell plate (50 mm) after overnight incubation.19911680352
characterization of a vaccinia virus-encoded double-stranded rna-binding protein that may be involved in inhibition of the double-stranded rna-dependent protein kinase.the work described in this article identifies a vaccinia virus-encoded protein that may be involved in inhibition of the interferon-induced, double-stranded rna-dependent protein kinase. extracts prepared from vaccinia virus (wr strain)-infected cells contain an inhibitor of this kinase. inhibition was reduced in extracts from which dsrna-binding proteins had been removed by preadsorption to poly(ri).poly(rc)-sepharose, suggesting that a dsrna-binding protein may be involved in kinase inhibition ...19911681618
v-erba overexpression is required to extinguish c-erba function in erythroid cell differentiation and regulation of the erba target gene caii.the v-erba oncoprotein represents a retrovirus-transduced oncogenic version of the thyroid hormone (t3/t4) receptor c-erba (type alpha). it contributes to virus-induced erythroleukemia by efficiently arresting differentiation of red cell progenitors and by suppressing transcription of erythrocyte-specific genes. here, we show that v-erba and c-erba bind directly to sequences within the promoter of the erythrocyte-specific carbonic anhydrase ii (caii), a gene whose transcription is efficiently su ...19911682217
site-specific interaction of vaccinia virus topoisomerase i with duplex dna. minimal dna substrate for strand cleavage in vitro. 19911682312
inability of plasmodium vinckei-immune spleen cells to transfer protection to recipient mice exposed to vaccine 'vectors' or heterologous species of plasmodium.mice can be immunized to plasmodium vinckei by repeated infections followed by cure. such immunity is dependent on cd4 t cells and an architecturally modified spleen, but has little requirement for antibody. thus, athymic mice can be exposed to p. vinckei and cured, but do not develop immunity. they are resistant to challenge with parasites, however, if they are then given spleen cells from euthymic immunized animals. such immune spleen cells, however, cannot transfer resistance to normal mice w ...19911683480
processing of nonstructural proteins ns4a and ns4b of dengue 2 virus in vitro and in vivo.the production, from polyprotein precursors, of two hydrophobic nonstructural proteins of dengue 2 (den2) virus, ns4a and ns4b, was analyzed both in cell-free systems and in infected cells. in den2-infected cells, ns4b is first produced as a peptide of apparent size 30 kda; ns4b is then post-translationally modified, in an unknown way, to produce a polypeptide of apparent size 28 kda. the rate and extent of ns4b modification was found to be cell-dependent; in bhk cells the half-time for the conv ...19911683727
immunobiology of infection with recombinant vaccinia virus encoding murine il-2. mechanisms of rapid viral clearance in immunocompetent mice.cd8+ cytotoxic t (tc) lymphocytes mediate recovery from vaccinia virus (vv) infection. in mice, anti-vv tc cells are detectable on or after day 3 after infection, and cytolytic activity peaks between days 5 and 6. a rvv encoding murine il-2, vv-hemagglutinin (ha)-il-2, was cleared more rapidly, compared with a control rvv, vv-ha-thymidine kinase (tk), from tissues of infected euthymic normal mice. the mechanism of vv-ha-il-2 clearance was operative early in infection and correlated with an eleva ...19911684375
editing of the sendai virus p/c mrna by g insertion occurs during mrna synthesis via a virus-encoded activity.two forms of the sendai virus p/c mrna have been predicted: one an exact copy of the viral genome, and the other with a single g insertion within a run of three g's. we directly cloned the mrna or portions of it containing the insertion site and screened the resulting colonies with oligonucleotides that could distinguish the presence of three or four g's at this position. we found that 31% of the mrnas did in fact contain the predicted insertion, whereas the viral genomes contained no heterogene ...19901688384
bovine dopamine beta-hydroxylase cdna. complete coding sequence and expression in mammalian cells with vaccinia virus vector.we have isolated cdna clones for bovine dopamine beta-hydroxylase from an adrenal medulla cdna library and have determined the complete coding sequence. the largest cdna clone isolated from the library is 2.4 kilobase pairs (kb) and contains an open reading frame of 1788 bases, coding for a protein of 597 amino acids and mr = 66,803. the predicted amino acid sequence of the bovine cdna contains 85% identity with human dopamine beta-hydroxylase (lamouroux, a., vingny, a., faucon biquet, n., darmo ...19901688549
vaccination against polyoma virus (pyv) tumors using vaccinia-pyv recombinants: a major tumor-specific transplantation antigen (tsta) epitope resides within the c-terminal segment of middle-t protein.we previously reported that inoculation of rats with live vaccinia virus (vv) recombinants vvpymt, vvpylt expressing either the middle-t (mt) or large-t (lt) proteins of polyomavirus (pyv) can elicit immunity to challenge with syngeneic pyv-tumor cells. we now report the results of cross-vaccination studies. vvpymt was ineffective against cells expressing lt protein but prevented development of mt-expressing cells. conversely, the vvpylt was ineffective against mt-expressing cells. in the two ex ...19901688831
production of human immunodeficiency virus (hiv)-like particles from cells infected with recombinant vaccinia viruses carrying the gag gene of hiv.we constructed a recombinant vaccinia virus carrying the entire gag and pol genes of human immunodeficiency virus type 1 (hiv-1). the main gene product detected in the lysates of infected cv-1 and sw480 cells was the gag precursor protein. however, in the culture fluid of infected sw480 cells, but not of infected cv-1 cells, reverse transcriptase (rt) activity was detected. the highest rt activity was found at a density of 1.15 g/ml and this fraction contained many round particles with diameters ...19901689917
chemically induced cd4 mutants of a human t cell line. evidence for dissociation between binding of hiv i envelope and susceptibility to hiv i infection and syncytia formation.this study describes the derivation of a series of mutants from the human leukemic cell line cem using the frame shift mutagen ethyl-methanesulfonate followed by negative selection with multiple treatments of okt4a + c, and sorting into cd4-, cd4-dull, and cd4-intermediate mutants. these mutants express reduced cd4 levels ranging from 0 to 60% of the parental line. the mutants were analyzed by staining with a battery of cd4-specific mab, by assessing their ability to bind soluble gp120, and by t ...19901690235
an epitope in human immunodeficiency virus 1 reverse transcriptase recognized by both mouse and human cytotoxic t lymphocytes.t-cell-mediated cytotoxicity may play an important role in control of infection by the human immunodeficiency virus (hiv). in this study, we have identified and characterized a relatively conserved epitope in the hiv-1 reverse transcriptase recognized by murine and human cytotoxic t cells. this epitope was identified using a murine antigen-specific cd8+ class i major histocompatibility complex-restricted cytotoxic t-cell (ctl) line, a transfected fibroblast cell line expressing the hiv-1 pol gen ...19901690429
presentation and immunogenicity of viral epitopes on the surface of hybrid hepatitis b virus core particles produced in bacteria.we recently reported the enhanced immunogenicity of a peptide epitope when it was presented as a fusion protein with hepatitis b core antigen. in those experiments the fusion protein was expressed in vaccinia virus. we have now refined the system so that large amounts of highly immunogenic particles can be produced using a simple bacterial expression system. we describe the expression of three different viral epitopes as chimeric particles that induce good antibody responses to each epitope afte ...19901693163
characterization and immunological properties of influenza a virus nucleoprotein (np): cell-associated np isolated from infected cells or viral np expressed by vaccinia recombinant virus do not confer protection.a nucleoprotein (np) preparation purified from the chorioallantoic membrane of chicken eggs infected with fowl plague virus (a/fpv/rostock/34, h7n1) yielded, in addition to the commonly known 56k protein, a 42k component that could not be detected in virus particles. after testing with a series of np-specific monoclonal antibodies it was found that some reacted with both proteins and others were bound only by the 56k protein. among both types of np-specific monoclonal antibodies only a limited n ...19901693165
in vitro binding and internalization of hiv envelope glycoproteins by human epidermal langerhans cells does not require the cd4-gp120-binding site.langerhans cells (lc) are epidermal dendritic cells which express several surface antigens, among them the cd4 antigens. recent data demonstrated that lc constitute target and storage cells for hiv. to better understand the interactions between hiv and lc, we investigated, in the present work, the fate of hiv envelope glycoproteins (gp120 and gp160) incubated with healthy human trypsinized lc in suspensions. after trypsin treatment, only the epitope for okt4 appeared to be resistant on lc. in th ...19901693220
identification of a bluetongue virus serotype 1-specific ovine helper t-cell determinant in outer capsid protein vp2.ovine t-cell lines (including one clone [101a]), which are specific for bluetongue virus serotype 1 (btv1), have been established and characterized. although these t-cell lines react with different isolates of btv1 (including those from south africa, australia, nigeria, and cameroon), they do not react with heterologous btv serotypes. antigen specificity of these t-cells was studied using purified virus particles, infectious subviral particles (isvp) and cores, or using individual btv structural ...19901693805
identification and characterization of c-terminal fragments of the beta-amyloid precursor produced in cell culture.the mechanism of amyloid formation in alzheimer's disease is unknown but appears to involve proteolytic processing of the amyloidogenic peptide from a larger precursor. when the c-terminus containing the amyloid-forming and cytoplasmic domains of the precursor was recombinantly expressed in cultured mammalian cells, a 16 kd protein accumulated which had a tendency to aggregate and form deposits. these deposits had physical characteristics resembling those of preamyloid. recombinant expression of ...19901694126
mammalian dna ligases. catalytic domain and size of dna ligase i.dna ligase i is the major dna ligase activity in proliferating mammalian cells. the protein has been purified to apparent homogeneity from calf thymus. it has a monomeric structure and a blocked n-terminal residue. dna ligase i is a 125-kda polypeptide as estimated by sodium dodecyl sulfate-gel electrophoresis and by gel chromatography under denaturing conditions, whereas hydrodynamic measurements indicate that the enzyme is an asymmetric 98-kda protein. immunoblotting with rabbit polyclonal ant ...19901695631
cytolytic t lymphocytes from the balb/c-h-2dm2 mouse recognize the vesicular stomatitis virus glycoprotein and are restricted by class ii mhc antigens.balb/c-h-2dm2 mice (h-2kdi-adi-eddd), a congenic strain of balb/c mice, have a deletion of the class i mhc ag, h-2ld. this gene encodes the exclusive class i mhc-restricting gene product for vesicular stomatitis virus-specific cytolytic t lymphocytes. when dm2 mice were immunized with infectious vesicular stomatitis virus, a specific ctl response was generated. these ctl lysed vsv-infected targets that expressed iad gene products, but not vsv-infected iad- targets. the ctl were used initially as ...19901695651
the respiratory syncytial virus subgroup b attachment glycoprotein: analysis of sequence, expression from a recombinant vector, and evaluation as an immunogen against homologous and heterologous subgroup virus challenge.the attachment glycoprotein g of respiratory syncytial (rs) virus is important in both the antigenic and molecular diversity of the rs viruses. previous work has shown that the glycoprotein g of a subgroup a rs virus expressed from a recombinant vaccinia virus provides significant protection against homologous but not heterologous subgroup virus challenge. we undertook the cdna cloning and nucleotide sequencing of the g mrna of a subgroup b rs virus (8/60) to extend molecular comparisons of the ...19901697126
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