Virology Commons^™

Cap-Independent Translational Enhancement Of Turnip Crinkle Virus Genomic And Subgenomic Rnas, Feng Qu, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

The presence of translational control elements and cap structures has not been carefully investigated for members of the Carmovirus genus, a group of small icosahedral plant viruses with positive-sense RNA genomes. In this study, we examined both the 5’ and 3’ untranslated regions (UTRs) of the turnip crinkle carmovirus (TCV) genomic RNA (4 kb) as well as the 5’ UTR of the coat protein subgenomic RNA (1.45 kb) for their roles in translational regulation. All three UTRs enhanced translation of the firefly luciferase reporter gene to different extents. Optimal translational efficiency was achieved when mRNAs contained both 5’ and 3’ …

Quantitative Image Analysis Of Simian Immunodeficiency Virus Replication In Macrophages Coinfected With Mycobacterium Avium Complex, Qingsheng Li, Keith G. Mansfield, Andrew Lackner, Ashley T. Haase

Qingsheng Li Publications

Mycobacterium avium is the most frequent cause of disseminated bacterial infection in patients with human immunodeficiency virus type 1 infection and in rhesus macaques with simian immunodeficiency virus (SIV) infection. This animal model of AIDS was used to test the hypothesis that this frequent association is the result of reciprocal enhancement of replication of both microorganisms. The replication of M. avium and SIV was analyzed in lymphatic tissues obtained from rhesus macaques experimentally inoculated with SIVmac who developed or remained free of overt M. avium infection. In situ hybridization, quantitative image analysis, and staining of M. avium and of macrophages …

Identification Of The Transactivation Domain Of The Transcription Factor Sox-2 And An Associated Co-Activator, Tamara K. Nowling, Lance R. Johnson, Matthew S. Wiebe, Angie Rizzino

Nebraska Center for Virology: Faculty Publications

The importance of interactions between Sox and POU transcription factors in the regulation of gene expression is becoming increasingly apparent. Recently, many examples of the involvement of Sox-POU partnerships in transcription have been discovered, including a partnership between Sox-2 and Oct-3. Little is known about the mechanisms by which these factors modulate transcription. To better understand the molecular interactions involved, we mapped the location of the transactivation do-main of Sox-2. This was done in the context of its interaction with Oct-3, as well as its ability to transactivate as a fusion protein linked to the DNA-binding domain of Gal4. Both …

The Molecular Epidemiology Of Rotavirus In Ireland, Fiona O'Halloran

Theses

Between 1997 and 1998, 3,136 cases of rotavirus diarrhoea were detected in Irish children less than 2 years of age. Hospital inpatients accounted for 80% of these infections, with the remainder being diagnosed in general practice. A large percentage of infections were detected in neonates, suggesting a possible inadequate maternal derived protection from existing indigenous strains. This feature suggested the possible existence of ‘novel’ strains circulating in Ireland. No data describing the epidemiology of rotavirus strains in this country currently exists. Furthermore no assessment of the potential health-economic impact or quantitation of potential disease burden was ever undertaken

Three hundred …

Azidothymidine And Interferon-Α Induce Apoptosis In Herpesvirus-Associated Lymphomas, Richard K. Lee, Jian-Ping Cai, Vadim Deyev, Parkash Gill, Lisa Cabral, Charles Wood, Ram Agarwal, Wenle Xia, Lawrence Boise, Eckhard Podack, William Harrington Jr.

Nebraska Center for Virology: Faculty Publications

Lymphoproliferative diseases that occur in immunocompromised patients are frequently associated with herpesviruses. These patients often fare poorly after treatment with conventional chemotherapy. We reported previously that patients with AIDS-related Burkitt’s lymphoma (BL) responded to parenteral azidothymidine (AZT) and IFN-α. We found that EBV-positive lymphoma cells derived from these patients cultured with AZT express CD95 and undergo apoptosis. AZT-mediated apoptosis was caspase dependent and occurred despite Fas receptor blockade. In contrast, EBV-negative lymphomas were resistant to AZT-induced apoptosis, as were EBV-positive lymphomas that expressed high levels of bcl-2. Primary effusion lymphoma (PEL) cell lines infected with human herpesvirus type 8 required …

A Study On The Effects Of The N-Terminal Amino Acid Sequence On The Activation Of Human T-Cell Leukemia Virus Type 1 Protease, Hidayah Muhammad Kendall

Chemistry & Biochemistry Theses & Dissertations

Human T-cell leukemia virus type 1 (HTL V-1) is dependent upon the enzymatic activity of its protease for maturation. Maturation of the protease is facilitated by cleavage of specific amino acid residues, followed by dimerization. The effects of the amino acid sequence located N-terminally to the cleavage site on the ability of the protease to become active were the focus of the current study. These amino acid sequences were contributed by the plasmid vector into which the protease gene was inserted.

Surface probability analyses (SPAs) of the vectors, as well as for native sequences which produce the mature protease and …

Lymphotropic Virions Affect Chemokine Receptor-Mediated Neural Signaling And Apoptosis: Implications For Human Immunodeficiency Virus Type 1-Associated Dementia, Jialin Zheng, Anuja Ghorpade, Douglas Niemann, Robin L. Cotter, Michael R. Thylin, Leon Epstein, Jennifer Swartz, Robin B. Shepard, Xiaojuan Liu, Adeline Nukuna, Howard E. Gendelman

Nebraska Center for Virology: Faculty Publications

Chemokine receptors pivotal for human immunodeficiency virus type 1 (HIV-1) infection in lymphocytes and macrophages (CCR3, CCR5, and CXCR4) are expressed on neural cells (microglia, astrocytes, and/or neurons). It is these cells which are damaged during progressive HIV-1 infection of the central nervous system. We theorize that viral coreceptors could effect neural cell damage during HIV-1-associated dementia (HAD) without simultaneously affecting viral replication. To these ends, we studied the ability of diverse viral strains to affect intracellular signaling and apoptosis of neurons, astrocytes, and monocyte-derived macrophages. Inhibition of cyclic AMP, activation of inositol 1,4,5-trisphosphate, and apoptosis were induced by diverse …

Broad-Spectrum Protection Against Tombusviruses Elicited By Defective Interfering Rnas In Transgenic Plants, Teresa Rubio, Marise Borja, Herman Scholthof, Paul A. Feldstein, Thomas Jack Morris, Andrew O. Jackson

Nebraska Center for Virology: Faculty Publications

We have designed a DNA cassette to transcribe defective interfering (DI) RNAs of tomato bushy stunt virus (TBSV) and have investigated their potential to protect transgenic Nicotiana benthamiana plants from tombusvirus infections. To produce RNAs with authentic 5’ and 3’ termini identical to those of the native B10 DI RNA, the DI RNA sequences were flanked by ribozymes (RzDI). When RzDI RNAs transcribed in vitro were mixed with parental TBSV transcripts and inoculated into protoplasts or plants, they became amplified, reduced the accumulation of the parental RNA, and mediated attenuation of the lethal syndrome characteristic of TBSV infections. Analysis of …

An Economic Analysis Of The Threat Of An Exotic Disease On Agriculture: The Case Of Sheep Pox In Western Australia, Nhu Che, Tom Kompas

Biosecurity published reports

Sheep pox is an acute disease that causes heavy losses due to high sheep mortality, costly eradication programs and ongoing problems with trade restrictions for many countries around the world. Australia until now has been unaffected, and although the risk of disease entry may be very slight, one case of sheep pox outbreak could cost the Western Australian economy as much as $50 million in damages, mostly from the trade disruption losses ( over the 21-month period of trading bans). The introduction of a Serology Test Program may reduce that amount by $35 million due to a shortening of the …

Multicenter Comparison Of Pcr Assays For Detection Of Human Herpesvirus 8 Dna In Semen, Philip E. Pellett, Thomas J. Spira, Omar Bagasra, Chris Boshoff, Lawrence Corey, Laura De Lellis, Meei-Li Huang, Jung-Chung Lin, Steve Matthews, Paolo Monini, Paola Romessi, Carlos Sosa, Charles Wood, John A. Stewart

Nebraska Center for Virology: Faculty Publications

Reported prevalences of human herpesvirus 8 (HHV-8) (Kaposi’s sarcoma-associated herpesvirus) in semen have ranged widely. This is possibly due to differences in assay sensitivity, geographic or population-based differences in the true presence of the virus in semen, and PCR contamination. This study assessed interlaboratory sensitivity and reproducibility in the analysis of blinded experimental panels, each consisting of 48 specimens and being composed of semen specimens from different healthy artificial-insemination donors (n = 30) and human immunodeficiency virus (HIV)-infected patients (n= 7) plus positive (n = 4) and negative (n = 7) controls. The experimental panels analyzed in each laboratory were …

Interferon Regulatory Factor 2 Represses The Epstein-Barr Virus BamHi Q Latency Promoter In Type Iii Latency, Luwen Zhang, Joseph S. Pagano

Nebraska Center for Virology: Faculty Publications

Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA-1) is the essential protein for maintenance of the EBV episome and establishment of latency. The BamHI Q promoter (Qp) is used for the transcription of EBNA-1 mRNA in type I and type II latency, which are EBV infection states exemplified by Burkitt’s lymphoma and nasopharyngeal carcinoma. However, Qp is inactive in type III latency, and other promoters (the BamHI C promoter and/or the BamHI W promoter) are used for EBNA-1. The involvement of interferon regulatory factors (IRFs) in the regulation of Qp is suggested by the presence of an essential interferon-stimulated response element …

Carmoviruses (Tombusviridae), Feng Qu, Thomas Jack Morris

School of Biological Sciences: Faculty Publications

Carmovirus is one of two officially recognized genera of Tombusviridae. Members of Tombusviridae all have icosahedral virions of about 30 nm in diameter with T = 3 symmetry that consists of 180 coat protein (CP) subunits of about 38- 43 kDa and a single-stranded (ss) RNA genome ranging in size from 4.0 to 4.7 kb. Carmoviruses share recognizable sequence similarity in both the polymerase and structural genes with members of the other genus, Tombusvirus. Sequence comparisons and phylogenetic analysis of these genes support the view that the genera are distinct but closely related. In addition, the genome organization of the …

Characterization Of The Jembrana Disease Virus Tat Gene And The Cis- And Trans-Regulatory Elements In Its Long Terminal Repeats, Hexin Chen, Graham Wilcox, Gde Kertayadnya, Charles Wood

Nebraska Center for Virology: Faculty Publications

Jembrana disease virus (JDV) is a newly identified bovine lentivirus that is closely related to the bovine immunodeficiency virus (BIV). JDV contains a tat gene, encoded by two exons, which has potent transactivation activity. Cotransfection of the JDV tat expression plasmid with the JDV promoter chloramphenicol acetyltransferase (CAT) construct pJDV-U3R resulted in a substantial increase in the level of CAT mRNA transcribed from the JDV long terminal repeat (LTR) and a dramatic increase in the CAT protein level. Deletion analysis of the LTR sequences showed that sequences spanning nucleotides 268 to 153, including the TATA box and the predicted first …

Influence Of The Ccr2-V64i Polymorphism On Human Immunodeficiency Virus Type 1 Coreceptor Activity And On Chemokine Receptor Function Of Ccr2b, Ccr3, Ccr5, And Cxcr4, Benhur Lee, Benjamin J. Doranz, Shalini Rana, Yanji Yi, Mario Mellado, Jose M. R. Frade, Carlos Martinez-A., Stephen J. O'Brien, Michael Dean, Ronald G. Collman, Robert W. Doms

Biology Faculty Articles

The chemokine receptors CCR5 and CXCR4 are used by human immunodeficiency virus type 1 (HIV-1) in conjunction with CD4 to infect cells. In addition, some virus strains can use alternative chemokine receptors, including CCR2b and CCR3, for infection. A polymorphism in CCR2 (CCR2-V64I) is associated with a 2- to 4-year delay in the progression to AIDS. To investigate the mechanism of this protective effect, we studied the expression of CCR2b and CCR2b-V64I, their chemokine and HIV-1 coreceptor activities, and their effects on the expression and receptor activities of the major HIV-1 coreceptors. CCR2b and CCR2b-V64I were expressed at …

Cytoplasmic Assembly And Accumulation Of Human Immunodeficiency Virus Types 1 And 2 In Recombinant Human Colony-Stimulating Factor-1-Treated Human Monocytes: An Ultrastructural Study, Jan Marc Orenstein, Monte S. Meltzer, Terri Phipps, Howard Gendelman

Nebraska Center for Virology: Faculty Publications

Recombinant human colony-stimulating factor-1-treated human peripheral blood-derived monocytes-macrophages are efficient host cells for recovery of the human immunodeficiency virus (HIV) from blood leukocytes of patients with acquired immunodeficiency syndrome. These cells can be maintained as viable monolayers for intervals exceeding 3 months. Infection with HIV resulted in virus-induced cytopathic effects, accompanied by relatively high levels of released progeny virus, followed by a prolonged low-level release of virus from morphologically normal cells. In both acutely and chronically infected monocytes, viral particles were seen budding into and accumulating within cytoplasmic vacuoles. The number of intravacuolar virions far exceeded those associated with the …

Biological Characterization Of Rev Variation In Equine Infectious Anemia Virus, Michael Belshan, Matthew E. Harris, Anne E. Shoemaker, Thomas J. Hope, Susan Carpenter

Nebraska Center for Virology: Faculty Publications

Sequence analysis identified significant variation in the second exon of equine infectious anemia virus (EIAV) rev. Functional analysis indicated that limited amino acid variation in Rev significantly altered the export activity of the protein but did not affect Rev-dependent alternative splicing. EIAV Rev can mediate export through two independent cis -acting Rev-responsive elements (RREs), and differences among Rev variants were more pronounced when both RREs were present. Variation in Rev may be an important mechanism for regulation of virus replication in vivo and may contribute to changes in clinical disease.

Human Immunodeficiency Virus Neurotropism: An Analysis Of Viral Replication And Cytopathicity For Divergent Strains In Monocytes And Microglia, Anuja Ghorpade, Adeline Nukuna, Myhanh Che, Sheryl 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 …

Role Of The Β-Chemokine Receptors Ccr3 And Ccr5 In Human Immunodeficiency Virus Type 1 Infection Of Monocytes And Microglia, Anuja Ghorpade, Meng Qi Xia, Bradley T. Hyman, Yuri Persidsky, Adeline Nukuna, Paul Bock, Myhanh Che, Janae Limoges, Howard Gendelman, Charles R. Mackay

Nebraska Center for Virology: Faculty Publications

Human immunodeficiency virus type 1 (HIV-1) infection in mononuclear phagocyte lineage cells (monocytes, macrophages, and microglia) is a critical component in the pathogenesis of viral infection. Viral replication in macrophages serves as a reservoir, a site of dissemination, and an instigator for neurological sequelae during HIV-1 disease. Recent studies demonstrated that chemokine receptors are necessary coreceptors for HIV-1 entry which determine viral tropism for different cell types. To investigate the relative contribution of the β -chemokine receptors CCR3 and CCR5 to viral infection of mononuclear phagocytes we utilized a panel of macrophage-tropic HIV-1 strains (from blood and brain tissue) to …

Adenovirus Preterminal Protein Binds To The Cad Enzyme At Active Sites Of Viral Dna Replication On 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) via an interaction mediated by the precursor of the terminal protein (pTP). The identities of cellular proteins involved in these complexes have remained obscure. We present evidence that pTP binds to a multifunctional pyrimidine biosynthesis enzyme found at replication domains on the NM. Far-Western blotting identified proteins of 150 and 240 kDa that had pTP binding activity. Amino acid sequencing of the 150-kDa band revealed sequence identity to carbamyl phosphate synthetase I (CPS I) and a high degree of homology to the related trifunctional enzyme known as …

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 …

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 …

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% …

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 …

Direct Demonstration Of Retroviral Recombination In A Rhesus Monkey, Dawn P. Wooley, Randall A. Smith, Susan Czajak, Ronald C. Desrosiers

Neuroscience, Cell Biology & Physiology Faculty Publications

Recombination may be an important mechanism for increasing variation in retroviral populations. Retroviral recombination has been demonstrated in tissue culture systems by artificially creating doubly infected cells. Evidence for retroviral recombination in vivo is indirect and is based principally on the identification of apparently mosaic human immunodeficiency virus type 1 genomes from phylogenetic analyses of viral sequences. We infected a rhesus monkey with two different molecularly cloned strains of simian immunodeficiency virus. One strain of virus had a deletion in vpx and vpr, and the other strain had a deletion in nef. Each strain on its own induced low virus …

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 …

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 …

Identification Of A Novel Antiapoptotic Functional Domain In Simian Virus 40 Large T Antigen., Suzanne D. Conzen, Christine A. Snay, Charles N. Cole

Dartmouth Scholarship

The ability of DNA tumor virus proteins to trigger apoptosis in mammalian cells is well established. For example, transgenic expression of a simian virus 40 (SV40) T-antigen N-terminal fragment (N-termTag) is known to induce apoptosis in choroid plexus epithelial cells. SV40 T-antigen-induced apoptosis has generally been considered to be a p53-dependent event because cell death in the brain is greatly diminished in a p53-/- background strain and is abrogated by expression of wild-type (p53-binding) SV40 T antigen. We now show that while N-termTags triggered apoptosis in rat embryo fibroblasts cultured in low serum, expression of full-length T antigens unable to …

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 …

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.

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 …