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Showing papers on "Virus published in 1983"


Journal ArticleDOI
20 May 1983-Science
TL;DR: From these studies it is concluded that this virus as well as the previous HTLV isolates belong to a general family of T-lymphotropic retroviruses that are horizontally transmitted in humans and may be involved in several pathological syndromes, including AIDS.
Abstract: A retrovirus belonging to the family of recently discovered human T-cell leukemia viruses (HTLV), but clearly distinct from each previous isolate, has been isolated from a Caucasian patient with signs and symptoms that often precede the acquired immune deficiency syndrome (AIDS). This virus is a typical type-C RNA tumor virus, buds from the cell membrane, prefers magnesium for reverse transcriptase activity, and has an internal antigen (p25) similar to HTLV p24. Antibodies from serum of this patient react with proteins from viruses of the HTLV-I subgroup, but type-specific antisera to HTLV-I do not precipitate proteins of the new isolate. The virus from this patient has been transmitted into cord blood lymphocytes, and the virus produced by these cells is similar to the original isolate. From these studies it is concluded that this virus as well as the previous HTLV isolates belong to a general family of T-lymphotropic retroviruses that are horizontally transmitted in humans and may be involved in several pathological syndromes, including AIDS.

6,658 citations


Journal ArticleDOI
01 May 1983-Cell
TL;DR: PMOV-psi- has a defect in the packaging of genomic RNA into virions but can provide in trans the products necessary for virion production, and can be used to produce helper-free stocks of natural or synthetic defective retroviruses.

1,810 citations


Journal ArticleDOI
20 May 1983-Science
TL;DR: Whether or not HTLV-I or other retroviruses of this family with T-cell tropism cause AIDS, it is possible that patients from whom the virus can be isolated can also transmit it to others.
Abstract: Several isolates of a human type-C retrovirus belonging to one group, known as human T-cell leukemia virus (HTLV), have previously been obtained from patients with adult T-cell leukemia or lymphoma. The T-cell tropism of HTLV and its prevalence in the Caribbean basin prompted a search for it in patients with the epidemic T-cell immune deficiency disorder known as AIDS. Peripheral blood lymphocytes from one patient in the United States and two in France were cultured with T-cell growth factor (TCGF) an shown to express HTLV antigens. Virus from the U.S. patient was isolated and characterized and shown to be related to HTLV subgroup I. The virus was also transmitted into normal human T cells from umbilical cord blood of a newborn. Whether or not HTLV-I or other retroviruses of this family with T-cell tropism cause AIDS, it is possible that patients from whom the virus can be isolated can also transmit it to others. If the target cell of AIDS is the mature T cell as suspected, the methods used in these studies may prove useful for the long-term growth of these cells and for the identification of antigens specific for the etiological agent of AIDS.

1,237 citations


Journal ArticleDOI
TL;DR: It is concluded that cytotoxic T cells play a part in recovery from influenza virus infection.
Abstract: In a study designed to determine whether cytotoxic T lymphocytes contribute to immunity against influenza virus infection, we inoculated 63 volunteers intranasally with live unattenuated influenza A/Munich/1/79 virus. Over the next seven days clinical observations were made, and the amount of virus shed was measured. The protective effects of preinfection serum antibody and of cytotoxic T-cell immunity against influenza A virus were assessed for each participant. All subjects with demonstrable T-cell responses cleared virus effectively. This response was observed in volunteers in all age groups, including those born after 1956, who did not have specific antibody and hence had probably not been exposed to this subtype of influenza A virus before. Cytotoxic T cells show cross-reactivity in their recognition of the different subtypes of influenza A virus, in contrast to the antibody response that is specific for each virus subtype. We conclude that cytotoxic T cells play a part in recovery from influenza virus infection.

949 citations


Journal ArticleDOI
01 Jun 1983-Virology
TL;DR: The binding of influenza virus to erythrocytes and host cells is mediated by the interaction of the viral hemagglutinin with cell surface receptors containing sialic acid, and receptor specificity appeared, to some extent, to be dependent on the species from which the virus was isolated.

926 citations


Journal ArticleDOI
05 May 1983-Nature
TL;DR: The catalytic sites of influenza virus neuraminidase are located on the upper corners of the box-shaped tetramer that forms the head of the molecule, and determinants form a nearly-continuous surface across the top of the monomer encircling the catalytic site.
Abstract: The catalytic sites of influenza virus neuraminidase are located on the upper corners of the box-shaped tetramer that forms the head of the molecule. Antigenic determinants form a nearly-continuous surface across the top of the monomer encircling the catalytic site. Approximately the same number of amino acid sequence changes occurred in these determinants between the years 1968 and 1975 as occurred in the antigenic sites of influenza virus haemagglutinin in the same period.

757 citations


Journal ArticleDOI
18 Feb 1983-Science
TL;DR: Nine new isolates of human T-cell leukemia-lymphoma virus (HTLV) were obtained from cells of seven patients with malignancies of mature T cells and from two clinically normal relatives of a T- cell leukemia patient.
Abstract: Nine new isolates of human T-cell leukemia-lymphoma virus (HTLV) were obtained from cells of seven patients with malignancies of mature T cells and from two clinically normal relatives of a T-cell leukemia patient. These people were from the United States, Israel, the West Indies, and Japan. The virus was detected in the fresh T cells and was isolated from the established T-cell lines. Each isolate is closely related to the first HTLV isolate, and all the new HTLV isolates were transmitted into normal human T cells obtained from the umbilical cord blood of newborns.

543 citations


Journal ArticleDOI
TL;DR: It is concluded that arginine-333 is essential for the integrity of an antigenic determinant and for the ability of rabies viruses to produce lethal infection in adult mice.
Abstract: The pathogenicity of fixed rabies virus strains for adult mice depends on the presence of an antigenic determinant on the viral glycoprotein. Two virus-neutralizing monoclonal antibodies have been used to identify this determinant. All pathogenic strains of fixed rabies virus bind to these antibodies and are neutralized by them, whereas nonpathogenic strains fail to react with these monoclonal antibodies and are not neutralized by them. Antigenic variants of the rabies virus with altered glycoprotein were selected by growing virus in the presence of one monoclonal antibody, 194-2. All variants that lost their ability to react with this antibody and an additional antibody, 248-8, were found to be nonpathogenic for adult mice. Analysis of tryptic peptides of the glycoproteins of pathogenic parent virus and nonpathogenic variants and the amino acid sequence of a specific variant tryptic peptide revealed that the change in pathogenicity corresponded to an amino acid substitution at position 333 of the glycoprotein molecule. The nucleotide sequence of the nonpathogenic variant glycoprotein gene contained a base change that confirmed the single amino acid substitution in the tryptic peptide replacing arginine-333 in the parental glycoprotein. We conclude that arginine-333 is essential for the integrity of an antigenic determinant and for the ability of rabies viruses to produce lethal infection in adult mice.

463 citations


Journal ArticleDOI
TL;DR: The described duration, specificity, and consistent relationship to immunity suggest that IgG antibody in respiratory secretions, derived entirely or partly from serum, is the most likely mediator of resistance to natural influenza.
Abstract: The observations summarized in this review indicate immunity to infection with type A influenza viruses is subtype specific since little or none is conveyed to subtypes possessing immunologically distinct HA and NA proteins. However, within a subtype, a prior antigenic experience with one variant may prevent or modify illness to another. The resulting degree of subtype immunity depends on the extent of relatedness between variants. Observations with H3N2 viruses indicate that homotypic resistance to subsequent infection and illness with the same virus is potent and of relatively long duration. The long lasting durability of such immunity was indicated by the epidemiologic pattern following the reappearance of H1N1 virus. Knowledge of the duration and specificity of immunity aids considerably in assessing mechanisms that account for host resistance to influenza. Recovery from influenza virus infection must involve a variety of humoral and cell-mediated immune mechanisms, and conclusions regarding the relative importance of each one are not possible at present. To prevent infection, involved immune mechanism(s) must account for: (a) subtype specificity, (b) reduced cross-reactivity of immunity for succeeding antigenic variants, (c) a long duration of immunity, and (d) immunity at the mucosal surface. Only antibody directed toward the HA molecule presently satisfies these properties and thus should be considered the major mediator of resistance to infection. Study of naturally occurring infection is needed for determining the duration and specificity of secretory IgA in nasal and lower respiratory secretions so as to establish its relative importance as a mediator of immunity. However, the described duration, specificity, and consistent relationship to immunity suggest that IgG antibody in respiratory secretions, derived entirely or partly from serum, is the most likely mediator of resistance to natural influenza.

449 citations


Journal ArticleDOI
01 Jan 1983-Nature
TL;DR: The existence of amino acid sequence homology between retroviral reverse transcriptase and the putative polymerases of HBV and CaMV is reported, suggesting the replication cycle of a plant virus, cauliflower mosaic virus, includes a reverse transcription step.
Abstract: In infected cells, the RNA genomes of RNA tumour viruses are copied into DNA by a virus-encoded reverse transcriptase enzyme1–3 This transfer of information from RNA into DNA was thought to be a unique feature of RNA tumour viruses3, but recent results suggest it may be a more general strategy Hepatitis B virus (HBV) has a double-stranded DNA genome, and it has recently been shown that the minus DNA strand of the HBV genome is copied from a plus-strand RNA template, leading to the suggestion that reverse transcription is central to the life cycle of HBV4–6 More recently it has been suggested that the replication cycle of a plant virus, cauliflower mosaic virus (CaMV), includes a reverse transcription step7–9 We report here the existence of amino acid sequence homology between retroviral reverse transcriptase and the putative polymerases of HBV and CaMV

434 citations


Journal ArticleDOI
TL;DR: The results indicate that the alpha gene inducer is a virion component located outside the capsid and that its function might be to stimulate the transcription of alpha genes by recognizing regulatory sites on viral DNAs or host cell products or both.
Abstract: Herpes simplex virus (HSV) genes form three groups, alpha, beta, and gamma, whose synthesis is coordinately regulated and sequentially ordered in a cascade fashion. Earlier studies by Post et al. (Cell 24:555-565, 1981) have shown that chimeric genes constructed by fusion of 5' noncoding leader and upstream sequences of alpha genes to the 5' noncoding leader and structural sequences of the viral thymidine kinase (TK), a beta gene, are regulated as alpha genes upon recombination into the viral genome. In cells converted from TK- to TK+ phenotype, these chimeric genes are induced by infection with homologous TK- virus. The induction of the resident chimeric gene does not require viral protein synthesis and is independent of the presence of functional alpha gene 4 product required for the expression of beta genes. In this paper, we report on the properties of the alpha-TK gene chimera resident in converted TK+ murine (L316) and human (I316) cells. Our results were as follows. (i) The pattern of induction of L316 cells exposed to 0.1, 1.0, and 10 PFU per cell suggested that exposure to competent virus is required for induction and that in untreated preparations this virus corresponds to infectious virus. (ii) UV light-irradiated virus was just as effective as untreated virus in inducing alpha-TK chimeras. (iii) HSV-1(HFEM)tsB7 induced the alpha-TK gene chimeras at the nonpermissive (39 degrees C) temperature; at 39 degrees C the parental HSV-1(HFEM)tsB7 capsids accumulate at nuclear pores and do not release viral DNA. (iv) The alpha-TK gene chimeras were not induced by infection with spontaneous TK- mutants of pseudorabies virus and bovine mammillitis virus or with human cytomegalovirus or adenovirus type 2 or by exposure to lysates of HSV-1-infected cells from which the virus was removed by centrifugation. These results indicate that the alpha gene inducer is a virion component located outside the capsid and that its function might be to stimulate the transcription of alpha genes by recognizing regulatory sites on viral DNAs or host cell products or both.

Journal ArticleDOI
07 Apr 1983-Nature
TL;DR: Potential live vaccines against hepatitis B virus have been produced and cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies toHBsAg.
Abstract: Potential live vaccines against hepatitis B virus have been produced. The coding sequence for hepatitis B virus surface antigen (HBsAg) has been inserted into the vaccinia virus genome under control of vaccinia virus early promoters. Cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies to HBsAg.

Journal ArticleDOI
TL;DR: Thirteen clones of hybrid cells which synthesize antibodies directed against the Rous sarcoma virus (RSV) transforming protein, pp60src, were isolated and several other clones had a low affinity for the viral yes, fps, and ros gene products which could be detected by in vitro phosphorylation of the transforming proteins after immunoprecipitation with the monoclonal antibody.
Abstract: Thirteen clones of hybrid cells which synthesize antibodies directed against the Rous sarcoma virus (RSV) transforming protein, pp60src, were isolated. Mouse myeloma cells were fused with spleen cells from mice that had been immunized with purified pp60src from bacterial recombinants which direct the synthesis of the RSV src gene. The hybridomas which survived the selection medium were screened by immunoprecipitation of pp60src from 32P-labeled lysates of RSV-transformed cells. Monoclonal antibodies produced by subclones derived from 13 hybridomas recognized pp60src encoded by the Schmidt-Ruppin and Prague strains of RSV and the cellular homolog of pp60src. Antibody from clone 261 had a high affinity for the viral yes gene product, and antibodies from clones 443 and 463 recognized the transforming proteins encoded by viruses containing the related transforming genes fps and ros. Several other clones had a low affinity for the viral yes, fps, and ros gene products which could be detected by in vitro phosphorylation of the transforming proteins after immunoprecipitation with the monoclonal antibody. All of the monoclonal antibodies allowed phosphorylation of pp60src and casein in an immune complex-bound reaction.

Journal Article
TL;DR: The hypothesis that NK cells act as a natural resistance mechanism to a number of virus infections, but suggest that their relative importance may vary from virus to virus, is suggested.
Abstract: The role of natural killer (NK) cells in the natural resistance of mice to infections by several viruses was examined. Mice were specifically depleted of NK cells by i.v. injection of rabbit antiserum to asialo GM1, a neutral glycosphingolipid present at high concentrations on the surface of NK cells. Control mice were left untreated or were injected with normal rabbit serum. Four to 6 hr later, these mice were infected with lymphocytic choriomeningitis virus (LCMV), mouse hepatitis virus (MHV), murine cytomegalovirus (MCMV), or vaccinia virus. The mice were sacrificed 3 days post-infection and assayed for virus in liver and spleen, spleen NK cell activity, and plasma interferon (IFN). All mice treated with anti-asialo GM1 antibody had drastically reduced NK cell-mediated lysis. Correlating with NK cell depletion, these mice had significantly higher (up to 500-fold) titers of MCMV, MHV, or vaccinia virus in their livers and spleens as compared to control mice. NK cell-depleted MCMV and MHV-infected mice had higher levels of plasma IFN than controls, correlating with the higher virus titers. These NK cell-depleted, virus-infected mice had more extensive hepatitis, assayed by the number of inflammatory foci in their livers, as compared to control virus-infected mice; these foci were also larger and contained more degenerating liver cells than those in control mice. In contrast to the results obtained with MHV, MCMV, and vaccinia virus, NK cell depletion had no effect on virus titers in the early stages of acute LCMV infection or during persistent LCMV infection. Mice depleted of NK cells had similar amounts of LCMV in their spleens and similar plasma IFN levels. Because this antibody to asialo GM1 does not impair other detectable immunologic mechanisms, these data support the hypothesis that NK cells act as a natural resistance mechanism to a number of virus infections, but suggest that their relative importance may vary from virus to virus.

Journal ArticleDOI
TL;DR: Evidence for a Host-Cell Nuclear Requirement for primary Transcription for Primary Transcription is found and evidence for overlapping Coding Regions using Diff erent Reading Frames in Viruses is found.
Abstract: PERSPECTIVES AND SUMMARy 468 MORPHOLOGY OF THE INFLUENZA VIRUS PARTICLE (VIRION) 469 GENOME STRUCTURE 471 The Segmented Genome 471 ASSigning Gene Functions to RNA Segments 472 Sequences Common to all RNA Segments 474 THE SEQUENCES OF INFLUENZA VIRUS RNA SEGMENTS 474 RNA Segments 1,2, and 3: Transcriptase-Associated Proteins PBI, PB2, and PA ... 476 RNA Segment 4: the Hemagglutinin (HA) 476 RNA Segment 5: the N uc/eocapsid Protein (N P) 481 RNA Segment 6: the Neuraminidase (N A) 482 RNA Segment 7: the Membrane Protein (M 1) and Nonstructural Protein (M2) ......... 484 RN A Segment 8: Nonstructural Proteins NS1 and NS2 487 Overlapping Coding Regions Using Diff erent Reading Frames in Viruses 489 INFLUENZA VIRUS TRANSCRIPTION AND REPLICATION 490 Evidence for a Host-Cell Nuclear Requirement for Primary Transcription 490 In Vitro Transcription of Influenza Virus mRN As 491 In Vivo Transcription of mRN As 494 Template A( )cRNA Synthesis 495 Virion RN A Synthesis 496 The Control of RNA SyntheSis 496 Spliced mRNAs and Their Controlled Synthesis 497 Subgenomic RN As: A Replication Error Produces Defective Interfering Particles .... 498 The Packaging of Eight RNA Segments 498 CONCLUDING REMARKS 499

Journal ArticleDOI
TL;DR: A method to introduce site-specific mutations into the genome of Autographa californica nuclear polyhedrosis virus demonstrated that the polyhedrin gene was not essential for the production of infectious virus and that deletion of certain sequences within the gene did not alter the control, or decrease the level of expression, ofpolyhedrin.
Abstract: We describe a method to introduce site-specific mutations into the genome of Autographa californica nuclear polyhedrosis virus. Specifically, the A. californica nuclear polyhedrosis virus gene for polyhedrin, the major protein that forms viral occlusions in infected cells, was mutagenized by introducing deletions into the cloned DNA fragment containing the gene. The mutagenized polyhedrin gene was transferred to the intact viral DNA by mixing fragment and viral DNAs, cotransfecting Spodoptera frugiperda cells, and screening for viral recombinants that had undergone allelic exchange. Recombinant viruses with mutant polyhedrin genes were obtained by selecting the progeny virus that did not produce viral occlusions in infected cells (occlusion-negative mutants). Analyses of occlusion-negative mutants demonstrated that the polyhedrin gene was not essential for the production of infectious virus and that deletion of certain sequences within the gene did not alter the control, or decrease the level of expression, of polyhedrin. An early viral protein of 25,000 molecular weight was apparently not essential for virus replication in vitro, as the synthesis of this protein was not detected in cells infected with a mutant virus.

Journal ArticleDOI
20 May 1983-Science
TL;DR: Serum samples from patients with AIDS and from matched and unmatched control subjects were examined for the presence of antibodies to cell membrane antigens associated with human T-cell leukemia virus.
Abstract: The acquired immune deficiency syndrome (AIDS), which has recently occurred at increasing rates in homosexual men, intravenous drug users, and others, is characterized by the development of Kaposi's sarcoma and several opportunistic infections including pneumonia caused by Pneumocystis carinii. Serum samples from patients with AIDS and from matched and unmatched control subjects were examined for the presence of antibodies to cell membrane antigens associated with human T-cell leukemia virus. Nineteen of 75 of the AIDS patients had antibodies directed to surface antigens of Hut 102, a reference T lymphoid cell line infected with leukemia virus, as did two of the 336 control subjects.

Journal ArticleDOI
TL;DR: The results demonstrate that the phosphoprotein of measles virus and a protein of herpes simplex virus type 1 crossreact with an intermediate filament protein of human cells, and indicate that these monoclonal antibodies recognize different antigenic determinants on the intermediate filament molecule.
Abstract: Using monoclonal antibodies, we demonstrate that the phosphoprotein of measles virus and a protein of herpes simplex virus type 1 crossreact with an intermediate filament protein of human cells. This intermediate filament protein, probably vimentin, has a molecular weight of 52,000, whereas the molecular weights of the measles viral phosphoprotein and the herpes virus protein are 70,000 and 146,000, respectively. Crossreactivity was shown by immunofluorescent staining of infected and uninfected cells and by immunoblotting. The monoclonal antibody against measles virus phosphoprotein did not react with herpes simplex virus protein and vice versa, indicating that these monoclonal antibodies recognize different antigenic determinants on the intermediate filament molecule. The significance of these results in explaining the appearance of autoantibodies during virus infections in humans is discussed.

Journal ArticleDOI
01 Aug 1983-Virology
TL;DR: Multiple immortalized, non-producer, human umbilical cord blood lymphocyte cultures developed by cocultivation or fusion of fresh cells with T cells cultured from leukemia-lymphoma patients are described.

Journal ArticleDOI
01 Jul 1983-Gene
TL;DR: Two Escherichia coli hybrid plasmids, each of which contains the entire 4.7-kb DNA genome of the human parvovirus, adeno-associated virus (AAV) type 2, are constructed to study the potential of AAV as a eukaryotic vector.

Journal ArticleDOI
TL;DR: The data suggest that the synthesis of alpha polypeptides in wild-type virus infections is subject to a negative post-transcriptional control involving viral gene product(s) present in infected cell lysates constituting virus stocks.
Abstract: Six mutants isolated from herpes simplex virus type 1 were judged to be defective with respect to the virion-associated function acting to rapidly shut off host polypeptide synthesis in herpes simplex virus-infected cells. The mutants were capable of proper entry into the cells, but, unlike the parent wild-type virus, they failed to shut off host polypeptide syntehsis in the presence of actinomycin D. They were consequently designated as virion-associated host shutoff (vhs) mutants. In the presence of actinomycin D, three of the mutants, vhs1, -2, and -3, failed to shut off the host at both 34 and 39 degrees C, whereas vhs4, -5, and -6 exhibited a temperature-dependent vhs phenotype. Since the mutants were capable of growth at 34 degrees C, it appeared that the vhs function was not essential for virus replication in cultured cells. Temperature-shift experiments performed with the vhs4 mutant showed that an active vhs function was required throughout the shutoff process and that, once established, the translational shutoff could not be reversed. In the absence of actinomycin D, the mutants induced a generalized, secondary shutoff of host translation, which required the synthesis of beta (early) or gamma (late) viral polypeptide(s). The vhs mutants appeared to be defective also with respect to post-transcriptional shutoff of alpha (immediate early) viral gene expression, since (i) cells infected with mutant viruses overproduced alpha viral polypeptides, (ii) there was an increased functional stability of alpha mRNA in the vhs1 mutant virus-infected cells, and (iii) superinfection of vhs1-infected cells with wild-type virus, in the presence of actinomycin D, resulted in a more pronounced shutoff of alpha polypeptide synthesis from preformed alpha mRNA than equivalent superinfection with vhs1 virus. The data suggest that the synthesis of alpha polypeptides in wild-type virus infections is subject to a negative post-transcriptional control involving viral gene product(s) present in infected cell lysates constituting virus stocks. The vhs1 mutant and possibly other vhs mutants contain a mutation in the gene encoding this function.

Journal ArticleDOI
TL;DR: Rabbits and hamsters inoculated intradermally with recombinant virus produced circulating antibodies that inhibited hemagglutination by influenza virus and vaccinated hamsters achieved levels of antibody similar to those obtained upon primary infection with influenza virus.
Abstract: A DNA copy of the influenza virus hemagglutinin gene, derived from influenza virus A/Jap/305/57 (H2N2) was inserted into the genome of vaccinia virus under the control of an early vaccinia virus promoter. Tissue culture cells infected with the purified recombinant virus synthesized influenza hemagglutinin, which was glycosylated and transported to the cell surface where it could be cleaved with trypsin into HA1 and HA2 subunits. Rabbits and hamsters inoculated intradermally with recombinant virus produced circulating antibodies that inhibited hemagglutination by influenza virus. Furthermore, vaccinated hamsters achieved levels of antibody similar to those obtained upon primary infection with influenza virus and were protected against respiratory infection with the A/Jap/305/57 influenza virus.

Journal ArticleDOI
23 Jun 1983-Nature
TL;DR: It is shown that cultivation of influenza B viruses in eggs selects subpopulations which are antigenically distinct from virus from the same source grown in mammalian cell cultures.
Abstract: Extensive antigenic variability and a capricious epidemiology are characteristics of influenza A and B viruses of man. The haemagglutinin (HA) undergoes frequent and progressive antigenic drift as a result of selection, under immunological pressure, of viruses possessing alterations in the amino acid sequences at specific sites in the molecule1. Here we present evidence for an additional selection mechanism for antigenic variants of influenza virus that depends on differing host cell tropisms of virus subpopulations. These studies were initiated after earlier observations of the occurrence of a marked degree of antigenic variation during passage of laboratory strains of influenza virus in eggs and cell cultures (J.C.J., in preparation). We have now shown that cultivation of influenza B viruses in eggs selects subpopulations which are antigenically distinct from virus from the same source grown in mammalian cell cultures. As antigenic characterization of influenza virus strains for epidemiological purposes2 and for the preparation of influenza vaccines3 conventionally relies on the cultivation of virus in eggs, our findings may have important practical implications for vaccine design and efficacy.

Journal ArticleDOI
TL;DR: Six monoclonal antibodies directed against respiratory syncytial virus proteins were produced and the anti-VP 70 antibody neutralized virus without complement and inhibited cell-cell fusion of previously infected HEp-2 cells, thus identifying VP 70 as the fusion protein.
Abstract: Six monoclonal antibodies directed against respiratory syncytial virus proteins were produced. Each was characterized by immunoprecipitation and indirect immunofluorescence. One was directed against the nucleocapsid protein. NP 44, two were directed against a 37,000-dalton protein, two were directed against the major envelope glycoprotein, GP 90, and one was directed against the 70,000-dalton envelope protein, VP 70. Indirect immunofluorescence stain patterns of infected HEp-2 cells defined GP 90 and VP 70 as viral proteins expressed on the cell surface, whereas NP 44 and the 37,000-dalton protein were detected as intracytoplasmic inclusions. One of the anti-GP 90 antibodies neutralized virus only in the presence of complement but did not inhibit cell-cell fusion. The anti-VP 70 antibody neutralized virus without complement and inhibited cell-cell fusion of previously infected HEp-2 cells, thus identifying VP 70 as the fusion protein.

Journal ArticleDOI
01 Jan 1983-Nature
TL;DR: In a child with hereditary spherocytosis who developed transient aplastic crisis, a strong inhibitory effect of the patient's serum on erythropoiesis correlated with the presence of virus, showing direct evidence for a role of SPLV in bone marrow aplasia.
Abstract: Viruses have been shown to cause bone marrow aplasia in animals and have been implicated in bone marrow failure in man; however, until recently, a specific link between human viral infection and bone marrow failure has not been proven. In 1975 Cossart and colleagues found a serum parvovirus-like virus (SPLV, sometimes referred to as B19) in human serum. Antibody to this virus is present in the sera of 30-45% of healthy adults (Y. E. Cossart, P. P. Mortimer, unpublished observations). However, evidence for a direct link came from work by Pattison et al. who found five children with transient aplastic crisis of sickle cell disease and evidence of active infection with SPLV. This association was later confirmed in a large series of children with sickle cell disease and aplastic crisis in Jamaica. We have studied the effects of virus-containing material on haematopoiesis, using in vitro colony-forming assays to look for direct evidence for a role of SPLV in bone marrow aplasia. We show here that SPLV-containing sera inhibit erythropoiesis in culture. Moreover, in a child with hereditary spherocytosis who developed transient aplastic crisis, a strong inhibitory effect of the patient's serum on erythropoiesis correlated with the presence of virus.

Journal ArticleDOI
TL;DR: A mutant of herpes simplex virus type 1, 17tsVP1201, has a temperature-sensitive processing defect in a late virus polypeptide, suggesting that the defect of the mutant was in the gene encoding p40 rather than in a gene of a processing enzyme.
Abstract: A mutant of herpes simplex virus type 1, 17tsVP1201, has a temperature-sensitive processing defect in a late virus polypeptide. Immunoprecipitation studies with monoclonal antibodies showed that the aberrant polypeptide in mutant virus-infected cells was the nucleocapsid polypeptide known as p40. Since a revertant, TS(+) for growth, processed the polypeptide normally under conditions restrictive for the mutant, the processing event must be essential for virus replication. Electron microscopic analysis of mutant virus-infected cells grown at the nonpermissive temperature revealed that the nuclei contained large aggregations of empty nucleocapsids possessing some internal structure. Therefore, although the mutant synthesized virus DNA at the nonpermissive temperature, the DNA was not packaged into nucleocapsids. When mutant virus-infected cells were shifted from 39 to 31 degrees C in the presence of cycloheximide, the polypeptide p40 was processed to lower-molecular-weight forms, and full nucleocapsids were detected in the cell nuclei. The aberrant polypeptide of the mutant, however, was not processed in cells mixedly infected with 17tsVP1201 and a revertant at the nonpermissive temperature, suggesting that the defect of the mutant was in the gene encoding p40 rather than in a gene of a processing enzyme.


Journal ArticleDOI
30 Jul 1983-Virology
TL;DR: The genetic heterogeneity generated upon passage of foot-and-mouth disease virus (FMDV) in cell culture has been evaluated by T1-oligonucleotide fingerprinting of genomic RNA, with some mutations present in only one of the cloned genomes analyzed.

Journal ArticleDOI
30 Nov 1983-Nature
TL;DR: Ability routinely to detect EBV DNA by in situ hybridization in epithelial cells of the oropharynx from persons with acute infectious mononucleosis suggests that, In vivo, EBV regularly gains access to and replicates lytically in epithelium cells.
Abstract: Epstein-Barr virus (EBV), a member of the herpes group of viruses and the aetiological agent of infectious mononucleosis, is usually thought of as a lymphotrophic virus with the ability to transform B lymphocytes. So the association of EBV with nasopharyngeal carcinoma is puzzling, especially given the lack of success of attempts to infect epithelial cells with EBV in culture and the apparent lack of EBV receptors on epithelial cells. Circumvention of the apparent requirement for membrane receptors by techniques of transfection, microinjection and receptor transplantation has clearly demonstrated that there is no inherent barrier to EBV replication in nonlymphoid cells, including epithelial cell types. Our ability routinely to detect EBV DNA by in situ hybridization in epithelial cells of the oropharynx from persons with acute infectious mononucleosis suggests that, in vivo, EBV regularly gains access to and replicates lytically in epithelial cells. We report here in vitro evidence for direct infection by EBV and replication of the virus in cultured normal human epithelial cells.

Journal ArticleDOI
TL;DR: The results are consistent with the tsB7 lesion being in a gene coding for a virion component which affects release of viral DNA from capsids and onset of viralDNA synthesis.
Abstract: Previous studies have shown that cells infected with the herpes simplex virus 1(HFEM) mutant tsB7 and maintained at the nonpermissive temperature fail to accumulate viral polypeptides. Analyses of intertypic recombinants generated by marker rescue of tsB7 with herpes simplex virus 2 DNA fragments localized the mutation between 0.46 and 0.52 map units on the viral genome (Knipe et al., J. Virol. 38:539-547, 1981). In this paper we report that the mutation in tsB7 affects several aspects of the reproductive cycle of the virus at the nonpermissive temperature. Thus, (i) viral capsids accumulate at the nuclear pores and do not release viral DNA for at least 6 h postinfection at 39 degrees C. The DNA was released within 30 min after a shift to the permissive temperature. (ii) Experiments involving shifts from the permissive to the nonpermissive temperature indicated that viral protein synthesis was not sustained in cells maintained at the permissive temperature for less than 4 h. (iii) Viral DNA synthesis was delayed at the permissive temperature for as long as 8 h. Once initiated, it continued at 39 degrees C. (iv) Marker rescue of tsB7 by transfection with herpes simplex virus 1(F) DNA fragments localized the mutation to between 0.501 and 0.503 map units on the viral genome. These results are consistent with the tsB7 lesion being in a gene coding for a virion component which affects release of viral DNA from capsids and onset of viral DNA synthesis.