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Articles 511 - 540 of 572

Full-Text Articles in Virology

Localization Of Human Cytomegalovirus Structural Proteins To The Nuclear Matrix Of Infected Human Fibroblasts, V. Sanchez, Peter C. Angeletti, J. A. Engler, W. J. Britt Apr 1998

Localization Of Human Cytomegalovirus Structural Proteins To The Nuclear Matrix Of Infected Human Fibroblasts, V. Sanchez, Peter C. Angeletti, J. A. Engler, W. J. Britt

Nebraska Center for Virology: Faculty Publications

The intranuclear assembly of herpesvirus subviral particles remains an incompletely understood process. Previous studies have described the nuclear localization of capsid and tegument proteins as well as intranuclear tegumentation of capsid-like particles. The temporally and spatially regulated replication of viral DNA suggests that assembly may also be regulated by compartmentalization of structural proteins. We have investigated the intranuclear location of several structural and nonstructural proteins of human cytomegalovirus (HCMV). Tegument components including pp65 (ppUL83) and ppUL69 and capsid components including the major capsid protein (pUL86) and the small capsid protein (pUL48/49) were retained within the nuclear matrix (NM), whereas the …

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Human Immunodeficiency Virus Neurotropism: An Analysis Of Viral Replication And Cytopathicity For Divergent Strains In Monocytes And Microglia, Anuja Ghorpade, Adeline Nukuna, Myhanh Che, Sherryl Haggerty, Yuri Persidsky, Eboni Carter, Leeroy Carhart, Laura Shafer, Howard Gendelman Apr 1998

Human Immunodeficiency Virus Neurotropism: An Analysis Of Viral Replication And Cytopathicity For Divergent Strains In Monocytes And Microglia, Anuja Ghorpade, Adeline Nukuna, Myhanh Che, Sherryl Haggerty, Yuri Persidsky, Eboni Carter, Leeroy Carhart, Laura Shafer, Howard Gendelman

Nebraska Center for Virology: Faculty Publications

Productive replication of human immunodeficiency virus type 1 (HIV-1) in brain macrophages and microglia is a critical component of viral neuropathogenesis. However, how virus-macrophage interactions lead to neurological disease remains incompletely understood. Possibly, a differential ability of virus to replicate in brain tissue macrophages versus macrophages in other tissues underlies HIV-1 neurovirulence. To these ends, we established systems for the isolation and propagation of pure populations of human microglia and then analyzed the viral life cycles of divergent HIV-1 strains in these cells and in cultured monocytes by using identical viral inocula and indicator systems. The HIV-1 isolates included those …

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Human Herpesvirus 8 As A Potential Sexually Transmitted Agent In Honduras, C. Sosa, W. Klaskala, B. Chandran, R. Soto, L. Sieczkowski, M. H. Wu, M. Baum, Charles Wood Jan 1998

Human Herpesvirus 8 As A Potential Sexually Transmitted Agent In Honduras, C. Sosa, W. Klaskala, B. Chandran, R. Soto, L. Sieczkowski, M. H. Wu, M. Baum, Charles Wood

Nebraska Center for Virology: Faculty Publications

The seroprevalence of human herpesvirus 8 (HHV-8) was studied in 326 human immunodeficiency virus (HIV)–positive and –negative persons from Honduras; women constituted 77% (n = 251) of the subjects. Sera were tested for lytic HHV-8 antibodies by an IFA, and positive samples were confirmed by a radioimmunoprecipitation assay. Of the 326 persons tested, 58 (17.8%) had HHV- 8 antibodies. Among the HIV-infected women, 22.7% were seropositive; 11.3% of the HIV-negative women were seropositive. HHV-8 seroprevalence was almost four times higher in HIV-positive female commercial sex workers (36%) than in HIV-negative female non–commercial sex workers (9.9%; odds ratio = 3.8, 95% …

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Seroprevalence Of Human Herpesvirus 8 Among Zambian Women Of Childbearing Age Without Kaposi’S Sarcoma (Ks) And Mother-Child Pairs With Ks, Jun He, Ganapati Bhat, Chipepo Kankasa, Chifumbe Chintu, Charles Mitchell, Wenjing Duan, Charles Wood Jan 1998

Seroprevalence Of Human Herpesvirus 8 Among Zambian Women Of Childbearing Age Without Kaposi’S Sarcoma (Ks) And Mother-Child Pairs With Ks, Jun He, Ganapati Bhat, Chipepo Kankasa, Chifumbe Chintu, Charles Mitchell, Wenjing Duan, Charles Wood

Nebraska Center for Virology: Faculty Publications

The seroprevalence of human herpesvirus 8 (HHV-8) among a group of Zambian women of reproductive age and among mother-child pairs in which either one of them has Kaposi’s sarcoma (KS) was determined. A cross-sectional group of 378 pregnant women was randomly recruited into the study, and 183 (48.4%) had HHV-8 antibodies. Among the human immunodeficiency virus (HIV)-1–infected women, 51.1% were HHV-8–seropositive, whereas of HIV- 1–negative women, 47.3% were HHV-8–seropositive. In addition, 21 women index patients with KS and 5 young children index patients with KS were studied. All children with KS had mothers who were HHV-8–seropositive, while not all children …

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Porcine Reproductive And Respiratory Syndrome Virus Replicates In Testicular Germ Cells, Alters Spermatogenesis, And Induces Germ Cell Death By Apoptosis, Jung-Hyang Sur, Alan R. Doster, James S. Christian, Judith A. Galeota, Robert W. Wills, Jeff J. Zimmerman, Fernando A. Osorio Dec 1997

Porcine Reproductive And Respiratory Syndrome Virus Replicates In Testicular Germ Cells, Alters Spermatogenesis, And Induces Germ Cell Death By Apoptosis, Jung-Hyang Sur, Alan R. Doster, James S. Christian, Judith A. Galeota, Robert W. Wills, Jeff J. Zimmerman, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

Like other arteriviruses, porcine reproductive and respiratory syndrome virus (PRRSV) is shed in semen, a feature that is critical for the venereal transmission of this group of viruses. In spite of its epidemiological importance, little is known of the association of PRRSV or other arteriviruses with gonadal tissues. We experimentally infected a group of boars with PRRSV 12068-96, a virulent field strain. By combined use of in situ hybridization and immunohistochemistry, we detected infection by PRRSV in the testes of these boars. The PRRSV testicular replication in testis centers on two types of cells: (i) epithelial germ cells of the …

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Irf-7, A New Interferon Regulatory Factor Associated With Epstein-Barr Virus Latency, Luwen Zhang, Joseph S. Pagano Oct 1997

Irf-7, A New Interferon Regulatory Factor Associated With Epstein-Barr Virus Latency, Luwen Zhang, Joseph S. Pagano

Nebraska Center for Virology: Faculty Publications

The Epstein-Barr virus (EBV) BamHI Q promoter (Qp) is the only promoter used for the transcription of Epstein-Barr virus nuclear antigen 1 (EBNA-1) mRNA in cells in the most restricted (type I) latent infection state. However, Qp is inactive in type III latency. With the use of the yeast one-hybrid system, a new cellular gene has been identified that encodes proteins which bind to sequence in Qp. The deduced amino acid sequence of the gene has significant homology to the interferon regulatory factors (IRFs). This new gene and products including two splicing variants are designated IRF-7A, IRF-7B, and IRF-7C. The …

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Transcriptional Patterns Of The Pcd41 (U27) Locus Of Human Herpesvirus 6, Yi Zhou, Bala Chandran, Charles Wood May 1997

Transcriptional Patterns Of The Pcd41 (U27) Locus Of Human Herpesvirus 6, Yi Zhou, Bala Chandran, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 6 (HHV-6) is a lymphotropic herpesvirus, and in vitro, it can productively infect many of the same cell types that human immunodeficiency virus (HIV) infects. Simultaneous infection of T cells by HIV and HHV-6 can lead to both activation of the HIV promoter and acceleration of the cytopathic effects. Several HHV-6 genes have been demonstrated to activate HIV promoter expression. Among them is a cDNA clone, pCD41 (U27), which codes for the HHV-6 DNA polymerase accessory protein. We have now further characterized the transcription pattern in the pCD41 locus and identified at least six RNA species, ranging in …

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Immune Suppression In Calves With Bovine Immunodeficiency Virus, Shucheng Zhang, Charles Wood, Wenzhi Xue, Samuel Krukenberg, Qimin Chen, Harish Minocha Mar 1997

Immune Suppression In Calves With Bovine Immunodeficiency Virus, Shucheng Zhang, Charles Wood, Wenzhi Xue, Samuel Krukenberg, Qimin Chen, Harish Minocha

Nebraska Center for Virology: Faculty Publications

The present study was designed to evaluate the effect of bovine immunodeficiency virus (BIV) infection on immune functions and possible interactions between BIV and other bovine viruses in calves. Ten calves were inoculated intravenously with BIV, and five served as controls. An increased lymphocyte proliferation to BIV gag protein was demonstrated 2 to 6 weeks after BIV inoculation (P < 0.05). Lymphocyte subset differentiation revealed a decreased CD4/CD8 ratio (P < 0.05) during weeks 2 to 7, suggesting a possible immune dysfunction in BIV-infected calves. When the calves were inoculated with bovine herpesvirus type 1 (BHV-1), the antibody response to BHV-1 in BIV-infected calves was delayed and the antibody titers were significantly lower (P < 0.05). Injection of bovine viral diarrhea virus vaccine also elicited a lower neutralizing antibody response in BIV-infected calves. The results indicated that immune suppression occurred in BIV-infected calves.

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Encapsidation Of Turnip Crinkle Virus Is Defined By A Specific Packaging Signal And Rna Size, Feng Qu, Thomas Jack Morris Feb 1997

Encapsidation Of Turnip Crinkle Virus Is Defined By A Specific Packaging Signal And Rna Size, Feng Qu, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

A protoplast infection assay has been used to reliably examine the viral RNA encapsidation of turnip crinkle virus (TCV). Analysis of the encapsidation of various mutant viral RNAs revealed that a 186-nucleotide (nt) region at the 3’ end of the coat protein (CP) gene, with a bulged hairpin loop of 28 nt as its most essential element, was indispensable for TCV RNA encapsidation. When RNA fragments containing the 186-nt region were used to replace the CP gene of a different virus, tomato bushy stunt virus, the resulting chimeric viral RNAs were encapsidated into TCV virions. Furthermore, analysis of the encapsidated …

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Detection Of Bovine Immunodeficiency Virus Antibodies In Cattle By Western Blot Assay With Recombinant Gag Protein, Shucheng Zhang, Wenzhi Xue, Charles Wood, Qi-Min Chen, Sanjay Capil, Harish Minocha Jan 1997

Detection Of Bovine Immunodeficiency Virus Antibodies In Cattle By Western Blot Assay With Recombinant Gag Protein, Shucheng Zhang, Wenzhi Xue, Charles Wood, Qi-Min Chen, Sanjay Capil, Harish Minocha

Nebraska Center for Virology: Faculty Publications

A western blot assay using purified recombinant bovine immunodeficiency virus gag protein has been developed for detection of bovine immunodeficiency virus antibodies in bovine serum samples. The test was standardized with known bovine immunodeficiency virus positive and negative bovine serum samples and the monoclonal antibody to gag protein. Both naturally and experimentally infected cattle sera demonstrated positive test results. The result of western blot assay was compared with polymerase chain reaction test results in 134 blood samples collected from Kansas. Twenty-six samples tested positive for bovine immunodeficiency virus DNA with polymerase chain reaction (18.7%) and 25 were positive for the …

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About The Cellular Tropism Of The Gammaherpesvirus Bovine Herpesvirus Type 4, Fernando A. Osorio, J. A. Galeota-Wheeler, D. E. Reed, O. Lopez Dec 1996

About The Cellular Tropism Of The Gammaherpesvirus Bovine Herpesvirus Type 4, Fernando A. Osorio, J. A. Galeota-Wheeler, D. E. Reed, O. Lopez

Nebraska Center for Virology: Faculty Publications

We read with interest the recent report by Egyed et al. (4) about the distribution in tissue, in the natural host, of bovine herpesvirus type 4 (BHV-4), a member of the gammaherpesvirus group. Using PCR, those authors were able to trace BHV-4 (Movar strain) in several tissues of experimentally infected cattle (mostly spleen, lung, trachea, and nasal epithelium tissues) at different times, ranging from 3 to 48 days postinfection. The authors also report consistent detection of BHV-4 DNA in what they consider to be a pure population of lymphocytes obtained from peripheral blood of the BHV-4- infected cattle, and then …

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Human Herpesvirus Type 8 Dna Sequences In Cell-Free Plasma And Mononuclear Cells Of Kaposi's Sarcoma Patients, William J. Harrington, Omar Bagasra, Carlos E. Sosa, Lisa E. Bobroski, Marianna Baum, Xue Lan Wen, Lisa Cabral, Gerald E. Byrne, Roger J. Pomerantz, Charles Wood Nov 1996

Human Herpesvirus Type 8 Dna Sequences In Cell-Free Plasma And Mononuclear Cells Of Kaposi's Sarcoma Patients, William J. Harrington, Omar Bagasra, Carlos E. Sosa, Lisa E. Bobroski, Marianna Baum, Xue Lan Wen, Lisa Cabral, Gerald E. Byrne, Roger J. Pomerantz, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus (HHV) type 8 bas been detected in both classical and AIDS-related Kaposi's sarcoma, body-cavity lymphomas, and other types of tumors. HHV-8 has also been detected in DNA from peripheral blood mononuclear cells (PBMC) of some Kaposi's sarcoma patients and more readily in B cell fractions derived from panned cell subpopulations. Two patients were followed using several methods: in situ hybridization, solution-based polymerase chain reaction (PCR), and in situ PCR. HHV-8 was intermittently detected in plasma and detection correlated with detection in PBMC. In situ PCR demonstrated HHV-8 sequences in both peripheral blood B lymphocytes and, to a lesser …

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In Vivo Detection Of Porcine Reproductive And Respiratory Syndrome Virus Rna By In Situ Hybridization At Different Times Post-Infection, Jung-Hyang Sur, Vicki Cooper, Judith A. Galeota, Richard A. Hesse, Alan R. Doster, Fernando A. Osorio Sep 1996

In Vivo Detection Of Porcine Reproductive And Respiratory Syndrome Virus Rna By In Situ Hybridization At Different Times Post-Infection, Jung-Hyang Sur, Vicki Cooper, Judith A. Galeota, Richard A. Hesse, Alan R. Doster, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

We studied the distribution of porcine reproductive and respiratory syndrome virus (PRRSV) RNA in tissues by in situ hybridization at different times postinfection (p.i.). The probe used for in situ hybridization was prepared by reverse transcription of PRRSV RNA, followed by PCR amplification of the cDNA. The sequence amplified corresponded to 433 bp from PRRSV open reading frame 7, which is contained in the nucleocapsid protein gene and which is highly conserved in both European and American strains (H. Mardassi, L. Wilson, S. Mounir, and S. Dea, J. Clin. Microbiol. 32:2197–2203, 1994). An immunohistochemical technique was used to detect PRRSV …

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Vif-Negative Human Immunodeficiency Virus Type 1 Persistently Replicates In Primary Macrophages, Producing Attenuated Progeny Virus, Iqbal Chowdhury, Wei Chao, Mary Jane Potash, Pavel Sova, Howard Gendelman, David J. Volsky Aug 1996

Vif-Negative Human Immunodeficiency Virus Type 1 Persistently Replicates In Primary Macrophages, Producing Attenuated Progeny Virus, Iqbal Chowdhury, Wei Chao, Mary Jane Potash, Pavel Sova, Howard Gendelman, David J. Volsky

Nebraska Center for Virology: Faculty Publications

The vif gene of human immunodeficiency virus type 1 (HIV-1) is required for efficient infection of primary T lymphocytes. In this study, we investigated in detail the role of vif in productive infection of primary monocyte-derived macrophages (MDM). Viruses carrying missense or deletion mutations in vif were constructed on the background of the monocytotropic recombinant NLHXADA-GP. Using MDM from multiple donors, we found that vif mutants produced in complementing or partially complementing cell lines were approximately 10% as infectious as wild-type virus when assayed for incomplete, complete, and circularized viral DNA molecules by quantitative PCR amplification or for viral core …

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Molecular Studies On Biv Infection And Its Interaction With Other Bovine Viruses, Charles Wood, Harish Minocha, Yunqi Geng Jun 1996

Molecular Studies On Biv Infection And Its Interaction With Other Bovine Viruses, Charles Wood, Harish Minocha, Yunqi Geng

Nebraska Center for Virology: Faculty Publications

Bovine immunodeficiency virus (BIV) is a bovine lentivirus that infects animals world-wide. The authors have cloned the BIV env and gag proteins and several sub-unit peptides spanning the entire coding regions of the two proteins as fusions to the bacterial trpE protein and expressed them in Escherichia coli (Spindler et al. 1984). These recombinant proteins can readily be expressed but the expression levels of these peptides varied. When these proteins were tested against a panel of bovine sera, only sera from BIV-infected animals reacted specifically. One major antigenic determinant was identified in the cartoxyl terminus of the p26 gag protein …

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Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood Jun 1996

Longitudinal Studies Of Viral Sequence, Viral Phenotype, And Immunologic Parameters Of Human Immunodeficiency Virus Type 1 Infection In Perinatally Infected Twins With Discordant Disease Courses, Cecelia Hutto, Yi Zhou, Jun He, Rebeca Geffin, Martin Hill, Walter Scott, Charles Wood

Nebraska Center for Virology: Faculty Publications

Perinatal human immunodeficiency virus type 1 (HIV-1) infections cause a broad spectrum of clinical disease and are variable in both the age of the patient at onset of serious disease and the progression of the clinical course. Heterozygotic perinatally infected twins with a marked difference in their clinical courses were monitored during the first 2 years of life. Twin B, the second-born twin, developed AIDS by 6 months of age and died at 22 months of age, while twin A remained minimally symptomatic through the first 2 years. Sequential blood specimens were obtained from the twins in order to characterize …

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Tyrosine Kinase-Dependent Release Of An Adenovirus Preterminal Protein Complex From The Nuclear Matrix, Peter C. Angeletti, Jeffrey A. Engler May 1996

Tyrosine Kinase-Dependent Release Of An Adenovirus Preterminal Protein Complex From The Nuclear Matrix, Peter C. Angeletti, Jeffrey A. Engler

Nebraska Center for Virology: Faculty Publications

Adenovirus (Ad) replicative complexes form at discrete sites on the nuclear matrix (NM) through the interaction of Ad preterminal protein (pTP). The NM is a highly salt-resistant fibrillar network which is known to anchor transcription, mRNA splicing, and DNA replication complexes. Incubation of rATP with NM to which pTP was bound caused the release of pTP as a pTP-NM complex with a size of 220 to 230 kDa; incubation with 5’ adenylylimidodiphosphate (rAMP-PNP) showed no significant release, indicating that rATP hydrolysis was required. With NM extracts, it was shown that a pTP-NM complex which was capable of binding Ad origin …

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Infection Of Primary Human Fetal Astrocytes By Human Herpesvirus 6, Jun He, Micheline Mccarthy, Yi Zhou, Bala Chandran, Charles Wood Feb 1996

Infection Of Primary Human Fetal Astrocytes By Human Herpesvirus 6, Jun He, Micheline Mccarthy, Yi Zhou, Bala Chandran, Charles Wood

Nebraska Center for Virology: Faculty Publications

Human herpesvirus 6 (HHV-6) is a lymphotropic betaherpesvirus which productively infects human CD4+ T cells and monocytes. HHV-6 is the etiologic agent for exanthem subitum (roseola), and it is well-known that central nervous system complications occur frequently during the course of HHV-6-associated disease. In addition, HHV-6 has been associated with encephalitis or encephalopathy. However, very little is known about its tropism for neural cells. There are reports that HHV-6 may infect some glial cell lines, but whether it can infect any primary neural cells is not known. Our studies show that both HHV-6A (GS) and HHV-6B (Z-29) can infect …

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Herpesvirus-Like Dna In Aids Kaposi’S Sarcoma In Argentina [Letter To The Editor], Carlos E. Sosa, Jorge A. Benetucci, Laura M. Sieczkowski, Anibal Vazquez, Xue-Lan Wen, Marianna Baum, Winslow Klaskala, William J. Harrington Jr., Charles Wood Jan 1996

Herpesvirus-Like Dna In Aids Kaposi’S Sarcoma In Argentina [Letter To The Editor], Carlos E. Sosa, Jorge A. Benetucci, Laura M. Sieczkowski, Anibal Vazquez, Xue-Lan Wen, Marianna Baum, Winslow Klaskala, William J. Harrington Jr., Charles Wood

Nebraska Center for Virology: Faculty Publications

First paragraph: Recently, Chang et al., using a new molecular biology technique termed Representational Difference Analysis, found herpesvirus-like DNA (KSHV) in AIDS patients with Kaposi’s sarcoma (KS). The presence of KSHV DNA sequences suggests that a new human herpesvirus may be associated with KS. The 5′ end of the 1853-bp flanking region of KSHV (nucleotides 1 to 607) was found to have 66 and 67% homologies to the corresponding regions of the major capsid protein gene of Herpesvirus Saimiri (ORF25) and Epstein Barr virus (BcLF1), respectively, both members of the gammaherpesvirus family. This finding is an important breakthrough, because a …

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Association Between Ns3 And Ns5 Proteins Of Dengue Virus Type 2 In The, Mini Kapoor, Luwen Zhang, Muralidhara Ramachandra, Jingo Kusukawa, Kurt E. Ebner, R. Padmanabhan Aug 1995

Association Between Ns3 And Ns5 Proteins Of Dengue Virus Type 2 In The, Mini Kapoor, Luwen Zhang, Muralidhara Ramachandra, Jingo Kusukawa, Kurt E. Ebner, R. Padmanabhan

Nebraska Center for Virology: Faculty Publications

Dengue virus type 2, a member of the family Flaviviridae, encodes a single polyprotein precursor consisting of 3391 amino acid residues that is processed to at least 10 mature proteins by host and viral proteases. The NS3 protein contains a domain commonly found in cellular serine proteinases that in cooperation with NS2B is involved in polyprotein processing. In addition, NS3 and NS5 proteins contain conserved motifs found in several RNA helicases and RNA-dependent RNA polymerases, respectively. Both enzymatic activities have been suggested to be involved in viral RNA replication. In this report, we demonstrate that the NS3 and NS5 proteins …

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Tumor Necrosis Factor Alpha-Induced Apoptosis In Human Neuronal Cells: Protection By The Antioxidant N-Acetylcysteine And The Genes Bcl-2 And Crma, Angela K. Talley, Stephen Dewhurst, Seth W. Perry, Sheila C. Dollard, Suryaram Gummuluru, Steven M. Fine, Deborah New, Leon Epstein, Howard Gendelman, Harris A. Gelbard May 1995

Tumor Necrosis Factor Alpha-Induced Apoptosis In Human Neuronal Cells: Protection By The Antioxidant N-Acetylcysteine And The Genes Bcl-2 And Crma, Angela K. Talley, Stephen Dewhurst, Seth W. Perry, Sheila C. Dollard, Suryaram Gummuluru, Steven M. Fine, Deborah New, Leon Epstein, Howard Gendelman, Harris A. Gelbard

Nebraska Center for Virology: Faculty Publications

Tumor necrosis factor alpha (TNF-α) is a candidate human immunodeficiency virus type 1-induced neurotoxin that contributes to the pathogenesis of AIDS dementia complex. We report here on the effects of exogenous TNF-α on SK-N-MC human neuroblastoma cells differentiated to a neuronal phenotype with retinoic acid. TNF-α caused a dose-dependent loss of viability and a corresponding increase in apoptosis in differentiated SK-N-MC cells but not in undifferentiated cultures. Importantly, intracellular signalling via TNF receptors, as measured by activation of the transcription factor NF-kB, was unaltered by retinoic acid treatment. Finally, overexpression of bcl-2 or crmA conferred resistance to apoptosis mediated by …

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Media Components Influence Viral Gene Expression Assays In Human Fetal Astrocyte Cultures, Micheline Mccarthy, Charles Wood, Larisa Fedoseyeva, Scott R. Whittemore Jan 1995

Media Components Influence Viral Gene Expression Assays In Human Fetal Astrocyte Cultures, Micheline Mccarthy, Charles Wood, Larisa Fedoseyeva, Scott R. Whittemore

Nebraska Center for Virology: Faculty Publications

In vitro neurovirological studies of viral infectivity or viral gene expression may be confounded by the mulHple neural cell types and/or fibrob last contamination present in early passage cultures prepared from dissociated human central nervous system (eNS) tissue. We have developed highly enriched astrocyte cultures for neurovirological study by culturing in a serum-free defined medium, 816, supplemented with basic fibroblast growth factor (FGF-2). Subculture in this medium selects against fibroblast proliferation and favors sustained proliferation of a highly enriched glial fibrillary acidic protein (GFAP)-positive cell population. These astrocytes support productive replication of cytomegalovirus (CMV) and transient expression of transfected CMVand …

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Correlation Between Precolonization Of Trigeminal Ganglia By Attenuated Strains Of Pseudorabies Virus And Resistance To Wild-Type Virus Latency, L. M. Schang, G. F. Kutish, Fernando A. Osorio Dec 1994

Correlation Between Precolonization Of Trigeminal Ganglia By Attenuated Strains Of Pseudorabies Virus And Resistance To Wild-Type Virus Latency, L. M. Schang, G. F. Kutish, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

We compared the levels of latent pseudorabies virus (PRV) DNA in trigeminal ganglia (TG) of pigs after intranasal inoculation of different PRV strains by using quantitative DNA PCR. The extent of colonization attained in each case varied significantly according to the type of strain and inoculum dose, wild-type (WT) PRV being the most efficient strain in colonizing TG. When groups of pigs representing different levels of precolonization of TG with an attenuated PRV strain were challenged with WT PRV, it became evident that there is a statistically significant inverse correlation between the extent of precolonization attained by an attenuated PRV …

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Alpha Interferon-Induced Antiretroviral Activities: Restriction Of Viral Nucleic Acid Synthesis And Progeny Virion Production In Human Immunodeficiency Virus Type 1-Infected Monocytes, Lisa Baca-Regen, Nina Heinzinger, Mario Stevenson, Howard Gendelman Nov 1994

Alpha Interferon-Induced Antiretroviral Activities: Restriction Of Viral Nucleic Acid Synthesis And Progeny Virion Production In Human Immunodeficiency Virus Type 1-Infected Monocytes, Lisa Baca-Regen, Nina Heinzinger, Mario Stevenson, Howard Gendelman

Nebraska Center for Virology: Faculty Publications

Alpha interferon (IFN-a) restricts multiple steps of the human immunodeficiency virus type 1 (HIV-i) life cycle. A well-described effect of IFN-a is in the modulation of viral nucleic acid synthesis. We demonstrate that IFN-α influences HIV-1 DNA synthesis principally by reducing the production of late products of reverse transcription. The magnitude of IFN-α-induced downregulation of HIV-1 DNA and/or progeny virion production was dependent on the IFN-α concentration, the duration of cytokine administration, the multiplicity of infection, the viral strain, and the cycles of viral infection. Interestingly, reductions in viral DNAs could not fully account for the observed IFN-a-induced abrogation of …

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Enhanced Competitiveness Of Tomato Bushy Stunt Virus Defective Interfering Rnas By Segment Duplication Or Nucleotide Insertion, K. Andrew White, Thomas Jack Morris Sep 1994

Enhanced Competitiveness Of Tomato Bushy Stunt Virus Defective Interfering Rnas By Segment Duplication Or Nucleotide Insertion, K. Andrew White, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

We have analyzed atypical tomato bushy stunt virus defective interfering (DI) RNA species which accumulated during a passage series in protoplasts. We present a rationale for the order of appearance of these molecules and show, using competition assays, that either segment duplication or single nucleotide insertion can enhance DI RNA competitiveness. Possible mechanisms for the introduction of the modifications observed in these DI RNAs are discussed.

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Purification And Characterization Of Two Forms Of A High-Molecular-Weight Cysteine Proteinase (Porphypain) From Porphyromonas Gingivalis, Pawel Ciborowski, Makoto Nishikata, Roger D. Allen, Marilyn S. Lantz Aug 1994

Purification And Characterization Of Two Forms Of A High-Molecular-Weight Cysteine Proteinase (Porphypain) From Porphyromonas Gingivalis, Pawel Ciborowski, Makoto Nishikata, Roger D. Allen, Marilyn S. Lantz

Nebraska Center for Virology: Faculty Publications

Porphyromonas gingivalis, an organism implicated in the etiology and pathogenesis of human periodontal diseases, produces a variety of potent proteolytic enzymes, and it has been suggested that these enzymes play a direct role in the destruction of periodontal tissues. We now report that two cell-associated cysteine proteinases of P. gingivalis W12, with molecular masses of approximately 150 kDa (porphypain-1) and 120 kDa (porphypain-2), as determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, have been separated and purified to apparent homogeneity. These proteinases appear to be SDS-stable conformational variants of a 180-kDa enzyme, and they are the largest cysteine proteinases …

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Molecular Analysis Of The Rfb Gene Cluster Of A Group D2 Salmonella Enterica Strain: Evidence For Its Origin From An Insertion Sequence-Mediated Recombination Event Between Group E And Dl Strains, Shi-Hua Xiang, Matthew Hobbs, Peter R. Reeves Jul 1994

Molecular Analysis Of The Rfb Gene Cluster Of A Group D2 Salmonella Enterica Strain: Evidence For Its Origin From An Insertion Sequence-Mediated Recombination Event Between Group E And Dl Strains, Shi-Hua Xiang, Matthew Hobbs, Peter R. Reeves

Nebraska Center for Virology: Faculty Publications

The Salmonella enterica O antigen is a highly variable surface polysaccharide composed of a repeated oligosaccharide (the O unit). The O unit produced by serogroup D2 has structural features in common with those of groups Dl and El, and hybridization studies had previously suggested that the D2 rfb gene cluster responsible for O-unit biosynthesis is indeed a hybrid of the two. In this study, the rfb gene cluster was cloned from a group D2 strain of S. enterica sv. Strasbourg. Mapping, hybridization, and DNA sequencing showed that the organization of the D2 rfb genes is similar to that of group …

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Nonhomologous Rna Recombination In Tombusviruses: Generation And Evolution Of Defective Interfering Rnas By Stepwise Deletions, K. Andrew White, Thomas Jack Morris Jan 1994

Nonhomologous Rna Recombination In Tombusviruses: Generation And Evolution Of Defective Interfering Rnas By Stepwise Deletions, K. Andrew White, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

We used a protoplast system to study the mechanisms involved in the generation and evolution of defective interfering (DI) RNAs of tomato bushy stunt tombusvirus (TBSV). Synthetic transcripts corresponding to different naturally occurring TBSV DI RNAs, or to various artificially constructed TBSV defective RNAs, were analyzed. The relative levels of competitiveness of different DI RNAs were determined by coinoculating their corresponding transcripts into protoplasts along with helper genomic RNA transcripts and monitoring the level of DI RNA accumulation. Further studies were performed to assess the contribution of naked DI RNA stability and DI RNA encapsidation efficiency to the observed levels …

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Infection Of Macrophages With Lymphotropic Human Immunodeficiency Virus Type 1 Can Be Arrested After Viral Dna Synthesis, Zheng-Bo Huang, Mary Jane Potash, Malgorzata Simm, Wei Chao, Howard Gendelman, Edward Edin, David J. Volsky Nov 1993

Infection Of Macrophages With Lymphotropic Human Immunodeficiency Virus Type 1 Can Be Arrested After Viral Dna Synthesis, Zheng-Bo Huang, Mary Jane Potash, Malgorzata Simm, Wei Chao, Howard Gendelman, Edward Edin, David J. Volsky

Nebraska Center for Virology: Faculty Publications

Lymphotropic strains of human immunodeficiency virus type 1 (HIV-1), including HTLV-IIIB, replicate poorly in macrophages. We have shown previously that lymphotropic HIV-1 fuses equally well with T lymphocytes and macrophages (M. J. Potash, M. Zeira, Z.-B. Huang, T. Pearce, E. Eden, H. Gendelman, and D. J. Volsky, Virology 188:864-868, 1992), suggesting that events in the virus life cycle following virus-cell fusion limit virus replication. We report here that HIV-1 DNA is synthesized effliciently in either ADA or HTLV-IIIB infected alveolar macrophages or monocyte-derived macrophages within 24 h of virus infection, as observed by polymerase chain reaction for amplification of viral …

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Isolation And Characterization Of New Wild-Type Isolates Of Bovine Lentivirus, David Suarez, Martin Van Der Maaten, Charles Wood, Ceclia Whetstone Aug 1993

Isolation And Characterization Of New Wild-Type Isolates Of Bovine Lentivirus, David Suarez, Martin Van Der Maaten, Charles Wood, Ceclia Whetstone

Nebraska Center for Virology: Faculty Publications

Two new isolates of bovine lentivirus, also known as bovine immunodeficiency-like virus (BIV), were obtained from a seropositive cattle herd in Florida. This is the first report of new isolates of BIV since the original BIV strain, R29, was isolated in 1%9. The two new BIV isolates were derived from blood butFy coat cells cocultivated in vitro with fetal bovine lung cell cultures. The new isolates differed in vitro from the original R29 isolate in replication and syncytium formation in fetal bovine lung cells. Both new isolates were confirmed as BIV by immunofluorescence assay, Western blotting (immunoblotting), and polymerase chain …

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