Virology Commons^™

Tryptophan 375 Stabilizes The Outer-Domain Core Of Gp120 For Hiv Vaccine Immunogen Design, Duoyi Hu, Dane Bowder, Wenzhong Wei, Jesse Thompson, Mark A. Wilson, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The outer-domain core of gp120 may serve as a better HIV vaccine immunogen than the full-length gp120 because of its greater stability and immunogenicity. In our previous report, we introduced two disulfide bonds to the outer-domain core of gp120 to fix its conformation into a CD4-bound state, which resulted in a significant increase in its immunogenicity when compared to the wild-type outer-domain core. In this report, to further improve the immunogenicity of the outer-domain core based immunogen, we have introduced a Tryptophan residue at gp120 amino acid sequence position 375 (375S/W). Our data from immunized guinea pigs indeed shows a …

Reactivation Of Hiv-1 Proviruses In Immune-Compromised Mice Engrafted With Human Voa-Negative Cd4+ T Cells, Zhe Yuan, Guobin Kang, Wuxun Lu, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Background: HIV-1 infection remains incurable on antiretroviral therapy (ART) due to virus latency. To date, enhanced co-culture assays, including viral outgrowth assays (VOA), are commonly used to measure HIV-1 latent reservoirs and evaluate latency-reversing agents (LRAs). However, VOA can only reactivate a small fraction of intact proviruses.

Methods: To explore the utility of NOD scid gamma (NSG) mice as an in vivo model to reactivate HIV-1 proviruses from VOA-negative CD4+ T cells, resting CD4+ T cells from an HIV-1 latently infected individual were isolated and the human CD4+ T cells corresponding to VOA-positive and VOA-negative CD4+ T cells were engrafted …

Characterization Of A New Chlorovirus Type With Permissive And Non-Permissive Features On Phylogenetically Related Algal Strains, Cristian F. Quispe, Ahmed Esmael, Olivia Sonderman, Michelle Mcquinn, Irina Agarkova, Mohammed Battah, Garry A. Duncan, David D. Dunigan, Timothy P. L. Smith, Cristina Decastro, Immacolata Speciale, Fangrui Ma, James L. Van Etten

Nebraska Center for Virology: Faculty Publications

A previous report indicated that prototype chlorovirus PBCV-1 replicated in two Chlorella variabilis algal strains, NC64A and Syngen 2-3, that are ex-endosymbionts isolated from the protozoan Paramecium bursaria. Surprisingly, plaque-forming viruses on Syngen 2-3 lawns were often higher than on NC64A lawns from indigenous water samples. These differences led to the discovery of viruses that exclusively replicate in Syngen 2-3 cells, named Only Syngen (OSy) viruses. OSy-NE5, the prototype virus for the proposed new species, had a linear dsDNA genome of 327 kb with 44-nucleotide-long, incompletely base-paired, covalently closed hairpin ends. Each hairpin structure was followed by an identical …

A Novel Codon-Optimized Siv Gag-Pol Immunogen For Gene-Based Vaccination, Catherine M. Crosby, Eric A. Weaver, Reeti Khare, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Simian immunodeficiency virus (SIV) is a robust pathogen used in non-human primates to model HIV vaccines. SIV encodes a number of potential vaccine targets. By far the largest and most conserved protein target in SIV is its gag-pol protein that bears many epitopes to drive multivalent immune T cell responses. While gag-pol is an attractive antigen, it is only translated after a frame shift between gag and pol with the effect that gag and pol are expressed at an approximate 10/1 ratio. The codon bias of native lentiviral genes are also mismatched with the abundance of tRNAs in mammalian cells …

Ebola Vp40 In Exosomes Can Cause Immune Cell Dysfunction, Michelle Pleet, Allison Mathiesen, Catherine Demarino, Yao Akpamagbo, Robert Barclay, Sergey N. Iordanskiy, +6 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Ebola virus (EBOV) is an enveloped, ssRNA virus from the family Filoviridae capable of causing severe hemorrhagic fever with up to 80–90% mortality rates. The most recent outbreak of EBOV in West Africa starting in 2014 resulted in over 11,300 deaths; however, long-lasting persistence and recurrence in survivors has been documented, potentially leading to further transmission of the virus. We have previously shown that exosomes from cells infected with HIV-1, HTLV-1 and Rift Valley Fever virus are able to transfer viral proteins and non-coding RNAs to naïve recipient cells, resulting in an altered cellular activity. In the current manuscript, we …

Transcriptomic Analysis Implicates The P53 Signaling Pathway In The Establishment Of Hiv-1 Latency In Central Memory Cd4 T Cells In An In Vitro Model, Cory White, Bastiaan Moesker, Nadejda Beliakova-Bethell, Laura Martins, Celsa Spina, Alberto Bosque, +4 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The search for an HIV-1 cure has been greatly hindered by the presence of a viral reservoir that persists despite antiretroviral therapy (ART). Studies of HIV-1 latency in vivo are also complicated by the low proportion of latently infected cells in HIV-1 infected individuals. A number of models of HIV-1 latency have been developed to examine the signaling pathways and viral determinants of latency and reactivation. A primary cell model of HIV-1 latency, which incorporates the generation of primary central memory CD4 T cells (TCM), full-length virus infection (HIVNL4-3) and ART to suppress virus replication, was used to investigate the …

Interleukin-17a Promotes Cd8 T Cell Cytotoxicity To Facilitate West Nile Virus Clearance, Amber M. Paul, Dhiraj Acharya, Penghua Wang, Jianfeng Dai, David Gate

Publications

CD8 T cells are crucial components of immunity and play a vital role in recovery from West Nile virus (WNV) infection. Here, we identify a previously unrecognized function of interleukin-17A (IL-17A) in inducing cytotoxic-mediator gene expression and promoting CD8 T cell cytotoxicity against WNV infection in mice. We find that IL-17A-deficient (Il17a/) mice are more susceptible to WNV infection and develop a higher viral burden than wild-type (WT) mice. Interestingly, the CD8 T cells isolated from Il17a/ mice are less cytotoxic and express lower levels of cytotoxic-mediator genes, which can be restored by supplying recombinant IL-17A in vitro and in …

Antiviral Cd8(+) T Cells Restricted By Human Leukocyte Antigen Class Ii Exist During Natural Hiv Infection And Exhibit Clonal Expansion., Srinika Ranasinghe, Pedro A Lamothe, Damien Z Soghoian, Samuel W Kazer, Michael B Cole, Alex K Shalek, Nir Yosef, R. Brad Jones, Faith Donaghey, Chioma Nwonu, Priya Jani, Gina M Clayton, Frances Crawford, Janice White, Alana Montoya, Karen Power, Todd M Allen, Hendrik Streeck, Daniel E Kaufmann, Louis J Picker, John W Kappler, Bruce D Walker

Microbiology, Immunology, and Tropical Medicine Faculty Publications

CD8(+) T cell recognition of virus-infected cells is characteristically restricted by major histocompatibility complex (MHC) class I, although rare examples of MHC class II restriction have been reported in Cd4-deficient mice and a macaque SIV vaccine trial using a recombinant cytomegalovirus vector. Here, we demonstrate the presence of human leukocyte antigen (HLA) class II-restricted CD8(+) T cell responses with antiviral properties in a small subset of HIV-infected individuals. In these individuals, T cell receptor β (TCRβ) analysis revealed that class II-restricted CD8(+) T cells underwent clonal expansion and mediated killing of HIV-infected cells. In one case, these cells comprised 12% …

An Ultrasensitive Electrogenerated Chemiluminescence-Based Immunoassay For Specific Detection Of Zika Virus, Amber M. Paul, Dhiraj Acharya, Pradip Bastola, Linda Le, Estenfani Fernandez, Michael S. Diamond, Wujian Miao, Fengwei Bai

Publications

Zika virus (ZIKV) is a globally emerging mosquito-transmitted flavivirus that can cause severe fetal abnormalities, including microcephaly. As such, highly sensitive, specific, and cost-effective diagnostic methods are urgently needed. Here, we report a novel electrogenerated chemiluminescence (ECL)-based immunoassay for ultrasensitive and specific detection of ZIKV in human biological fluids. We loaded polystyrene beads (PSB) with a large number of ECL labels and conjugated them with anti-ZIKV monoclonal antibodies to generate anti-ZIKV-PSBs. These anti-ZIKV-PSBs efficiently captured ZIKV in solution forming ZIKV-anti-ZIKV-PSB complexes, which were subjected to measurement of ECL intensity after further magnetic beads separation. Our results show that the anti-ZIKV-PSBs …

Hepatic Fibrosis And Immune Phenotype Vary By Hcv Viremia In Hcv/Hiv Co-Infected Subjects: A Women's Interagency Hiv Study., Seema N Desai, Jennifer L Dodge, Alan L Landay, Marshall J Glesby, Patricia S. Latham, Maria C Villacres, Audrey L French, Stephen J Gange, Ruth M Greenblatt, Marion G Peters

Pathology Faculty Publications

HCV and HIV independently lead to immune dysregulation. The mechanisms leading to advanced liver disease progression in HCV/HIV coinfected subjects remain unclear.

In this cross-sectional study, we assessed the association of HCV viremia, liver fibrosis, and immune response patterns in well-characterized HIV phenotypes: Elite controllers (Elites), HIV controlled (ARTc), and HIV uncontrolled (ARTuc) matched by age and race. Groups were stratified by HCV RNA status. Regulatory T-cell frequencies, T-cell activation (HLADR+CD38+), apoptosis (Caspase-3+), and intracellular cytokines (interferon-γ, IL-2, IL-17) were assessed using multiparametric flow-cytometry. Liver fibrosis was scored by AST to platelet ratio index (APRI).

We found liver fibrosis (APRI) …

Mucosal Vaccination By Adenoviruses Displaying Reovirus Sigma 1, Eric A. Weaver, Zenaido T. Camacho, Matthew L. Hillestad, Catherine M. Crosby, Mallory A. Turner, Adam J. Guenzel, Hind J. Fadel, George T. Mercier, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

We previously developed adenovirus serotype 5 (Ad5) vectors displaying the sigma 1 protein from reovirus as mucosal vaccines. Ad5-sigma retargets to JAM-1 and sialic acid, but had 40-fold reduced gene delivery when compared to Ad5. While weaker at transduction, Ad5-sigma generated stronger T cell responses than Ad5 when used for mucosal immunization. New Ad5-fiber-sigma vectors were generated here by varying the number of fiber β-spiral shaft repeats (R) fused between fiber tail and the sigma. Ad5 virions encoding R3, R14, and R20 chimeras were rescued. Increasing chimera length led to their decreasing encapsidation of these proteins in the virions. Ad5-R3 …

The Frequency Of Influenza And Bacterial Co-Infection: A Systematic Review And Meta-Analysis., Eili Y. Klein, Bradley Monteforte, Alisha Gupta, Wendi Jiang, Larissa May, Yu-Hsiang Hsieh, Andrea Freyer Dugas

Emergency Medicine Faculty Publications

AIM: Co-infecting bacterial pathogens are a major cause of morbidity and mortality in influenza. However, there remains a paucity of literature on the magnitude of co-infection in influenza patients.

METHOD: A systematic search of MeSH, Cochrane Library, Web of Science, SCOPUS, EMBASE, and PubMed was performed. Studies of humans in which all individuals had laboratory confirmed influenza, and all individuals were tested for an array of common bacterial species, met inclusion criteria.

RESULTS: Twenty-seven studies including 3,215 participants met all inclusion criteria. Common etiologies were defined from a subset of eight articles. There was high heterogeneity in the results (I(2) …

A Single Exercise Bout Enhances The Manufacture Of Viral-Specific T-Cells From Healthy Donors: Implications For Allogeneic Adoptive Transfer Immunotherapy, Guillaume Spielmann, Catherine Bollard, Hawley Kunz, Patrick J. Hanley, Richard J. Simpson

Pediatrics Faculty Publications

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections remain a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). The adoptive transfer of donor-derived viral-specific cytotoxic T-cells (VSTs) is an effective treatment for controlling CMV and EBV infections after HSCT; however, new practical methods are required to augment the ex vivo manufacture of multi-VSTs from healthy donors. This study investigated the effects of a single exercise bout on the ex vivo manufacture of multi-VSTs. PBMCs isolated from healthy CMV/EBV seropositive participants before (PRE) and immediately after (POST) 30-minutes of cycling exercise were stimulated with CMV (pp65 and …

Stabilization Of Gp120 Outer Domain For Hiv-1-1 Vaccine Immunogen Design, Duoyi Hu

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

The sole envelope glycoprotein spike on the surface of Human Immunodeficiency Virus (HIV-1) is composed of two subunits: gp120 and gp41. The gp120 consists of three domains: the inner domain, outer domain and bridging sheet, to which the viral primary receptor CD4 binds and induces a conformational change in gp120 to expose the co-receptor binding site. Previous studies have found that the outer domain of gp120 is relatively more stable than the inner domain and bridging sheet. When superimposed, the co-crystal structures of CD4-gp120 complex and VRC01-gp120 complex revealed that the CD4-binding site (CD4-BS) antibody VRC01 actually mainly bound to …

Circulating Fibroblast Growth Factor-2, Hiv-Tat, And Vascular Endothelial Cell Growth Factor-A In Hiv-Infected Children With Renal Disease Activate Rho-A And Src In Cultured Renal Endothelial Cells., Jharna R Das, J Silvio Gutkind, Patricio E. Ray

Pediatrics Faculty Publications

Renal endothelial cells (REc) are the first target of HIV-1 in the kidney. The integrity of REc is maintained at least partially by heparin binding growth factors that bind to heparan sulfate proteoglycans located on their cell surface. However, previous studies showed that the accumulation of two heparin-binding growth factors, Vascular Endothelial Cell Growth Factor-A (VEGF-A) and Fibroblast Growth Factor-2 (FGF-2), in combination with the viral protein Tat, can precipitate the progression of HIV-renal diseases. Nonetheless, very little is known about how these factors affect the behavior of REc in HIV+ children. We carried out this study to determine how …

Lineage-Specific Differences In The Gp120 Inner Domain Layer 3 Of Human And Simian Immunodeficiency Viruses, Shilei Ding, Halima Medjahed, Jérémie Prévost, Mathieu Coutu, Shi-Hua Xiang, Andrés Finzi

Nebraska Center for Virology: Faculty Publications

Binding of HIV-1 and SIV gp120 exterior envelope glycoprotein to CD4 triggers conformational changes in gp120 that promote its interaction with one of the chemokine receptors, usually CCR5, ultimately leading to gp41-mediated virus-cell membrane fusion and entry. We previously described that topological Layers (Layer 1, Layer 2 and Layer 3) in the gp120 inner domain contribute to gp120-trimer association in the unliganded state but also help secure CD4 binding. Relative to Layer 1 of HIV-1 gp120, the SIVmac239 gp120 Layer 1 plays a more prominent role in maintaining gp120-trimer association but is minimally involved in promoting CD4 binding, which could …

Human Herpesvirus Multiplex Ddpcr Detection In Brain Tissue From Low- And High-Grade Astrocytoma Cases And Controls., Cheng-Te Major Lin, Emily C. Leibovitch, M. Isabel Almira-Suarez, Steven Jacobson

Pathology Faculty Publications

BACKGROUND: Glioblastoma (GBM) is a fatal CNS malignancy, representing 50 % of all gliomas with approximately 12-18 months survival time after initial diagnosis. Recently, the human herpesvirus cytomegalovirus (CMV) has been suggested to have an oncogenic role, yet this association remains controversial. In addition, human herpesvirus 6 (HHV-6) and Epstein-Barr virus (EBV) have also been associated with low-grade gliomas, but few studies have examined HHV-6 and EBV in glioblastomas. Droplet digital PCR (ddPCR) is a highly precise diagnostic tool that enables the absolute quantification of target DNA. This study examines the association between multiple human herpesviruses and astrocytomas.

METHODS: This …

Giant Chloroviruses: Five Easy Questions, James L. Van Etten, David Dunigan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large, icosahedral, dsDNA-containing viruses that replicate in certain unicellular, chlorella-like green algae [1,2]. They exist in freshwater throughout the world with titers as high as thousands of plaque-forming units (PFU) per ml of indigenous water although titers are typically 1–100 PFU/ml. Titers fluctuate during the year with the highest titers typically occurring in the spring and late fall. Known chlorovirus hosts, which are normally symbionts and are often referred to as zoochlorellae, are associated with either the protozoan Paramecium bursaria (Fig 1A), the coelenterate Hydra viridis, or the heliozoan Acanthocystis turfacea. Zoochlorellae are resistant to viruses …

Genetic Barrier To Direct Acting Antivirals In Hcv Sequences Deposited In The European Databank, Dimas Alexandre Kliemann, Cristiane Valle Tovo, Ana Beatriz Gorini Da Veiga, André Luiz Machado, John T. West

Nebraska Center for Virology: Faculty Publications

Background & Aims: Development of resistance results from mutations in the viral genome, and the presence of selective drug pressure leads to the emergence of a resistant virus population. The aim of this study was to analyze the impact of genetic variability on the genetic barrier to drug resistance to DAAs.

Methods: The genetic barrier was quantified based on the number and type of nucleotide mutations required to impart resistance, considering full-length HCV NS3, NS5A and NS5B regions segregated by genotype into subtypes 1a, 1b, 2a, 2b and 3a. This study analyzed 789 NS3 sequences, 708 sequences and 536 NS5B …

Kaposi’S Sarcoma-Associated Herpesvirus Reduces Cellular Myeloid Differentiation Primary-Response Gene 88 (Myd88) Expression Via Modulation Of Its Rna, Amy Lingel, Erica Ehlers, Qianli Wang, Mingxia Cao, Charles Wood, Rongtuan Lin, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma (KS)-associated herpesvirus (KSHV) is a human gammaherpesvirus associated with several human malignancies. The replication and transcription activator (RTA) is necessary and sufficient for the switch from KSHV latency to lytic replication. Interleukin 1 (IL-1) is a major mediator for inflammation and plays an important role in both innate and adaptive immunity. Myeloid differentiation primary response gene 88 (MyD88) is an essential adaptor molecule for IL-1 as well as most Toll-like receptor signaling. In this study, we identified a novel mechanism by which KSHV interferes with host inflammation and immunity. KSHV RTA specifically reduces the steady-state protein levels of …

Nf45 And Nf90 Bind Hiv-1 Rna And Modulate Hiv Gene Expression, Yan Li, Michael Belshan

Nebraska Center for Virology: Faculty Publications

A previous proteomic screen in our laboratory identified nuclear factor 45 (NF45) and nuclear factor 90 (NF90) as potential cellular factors involved in human immunodeficiency virus type 1 (HIV-1) replication. Both are RNA binding proteins that regulate gene expression; and NF90 has been shown to regulate the expression of cyclin T1 which is required for Tat-dependent trans-activation of viral gene expression. In this study the roles of NF45 and NF90 in HIV replication were investigated through overexpression studies. Ectopic expression of either factor potentiated HIV infection, gene expression, and virus production. Deletion of the RNA binding domains of NF45 …

Mucosal Vaccination By Adenoviruses Displaying Reovirus Sigma 1, Eric A. Weaver, Zenaido T. Camacho, Matthew L. Hillestad, Catherine M. Crosby, Mallory A. Turner, Adam J. Guenzel, Hind J. Fadel, George T. Mercier, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

We previously developed adenovirus serotype 5 (Ad5) vectors displaying the sigma 1 protein from reovirus as mucosal vaccines. Ad5-sigma retargets to JAM-1 and sialic acid, but had 40-fold reduced gene delivery when compared to Ad5. While weaker at transduction, Ad5-sigma generated stronger T cell responses than Ad5 when used for mucosal immunization. New Ad5- fiber-sigma vectors were generated here by varying the number of fiber β-spiral shaft repeats (R) fused between fiber tail and the sigma. Ad5 virions encoding R3, R14, and R20 chimeras were rescued. Increasing chimera length led to their decreasing encapsidation of these proteins in the virions. …

Recapitulating Cross-Species Transmission Of Sivcpz To Humans Using Humanized-Blt Mice, Zhe Yuan, Guobin Kang, Fangrui Ma, Wuxun Lu, Wenjin Fan, Christine M. Fennessey, Brandon F. Keele, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The origins of HIV-1 have been widely accepted to be the consequence of simian immunodeficiency viruses from wild chimpanzees (SIVcpz) crossing over to humans. However, there has not been any in vivo study of SIVcpz infection of humans. Also, it remains largely unknown why only specific SIVcpz strains have achieved cross-species transmission and what transmission risk might exist for those SIVcpz strains that have not been found to infect humans. Closing this knowledge gap is essential for better understanding cross-species transmission and predicting the likelihood of additional cross-species transmissions of SIV into humans. Here we show hu-BLT mice are susceptible …

High Glucose Induces Reactivation Of Latent Kaposi’S Sarcoma-Associated Herpesvirus, Fengchun Ye, Yan Zeng, Jingfeng Sha, Tiffany Jones, Kurt Kuhne, Charles Wood, Shou-Jiang Gao

Nebraska Center for Virology: Faculty Publications

High prevalence of Kaposi’s sarcoma (KS) is seen in diabetic patients. It is unknown if the physiological condition of diabetes contributes to KS development. We found elevated levels of viral lytic gene expression when Kaposi’s sarcoma-associated herpesvirus (KSHV) infected cells were cultured in high glucose medium. To demonstrate the association between high glucose and KSHV replication, we xeno29

grafted telomerase-immortalized human umbilical vein endothelial cells that are infected with KSHV (TIVE-KSHV) into hyperglycemic and normal nude mice. The injected cells expressed significantly higher levels of KSHV lytic genes in hyperglycemic mice than in normal mice. We further demonstrated that high …

Persistent Low-Level Replication Of Sivδnef Drives Maturation Of Antibody And Cd8 T Cell Responses To Induce Protective Immunity Against Vaginal Siv Infection, Sama Adnan, R. Keith Reeves, Jacqueline Gillis, Fay E. Wong, Yi Yu, Jeremy V. Camp, Qingsheng Li, Michelle Connole, Yuan Li, Michael Piatak Jr., Jeffrey D. Lifson, Wenjun Li, Brandon F. Keele, Pamela A. Kozlowski, Ronald C. Desrosiers, Ashley T. Haase, R. Paul Johnson

Nebraska Center for Virology: Faculty Publications

Defining the correlates of immune protection conferred by SIVΔnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVΔnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVΔnef …

Complete Genome Sequence Of Highly Virulent Porcine Reproductive And Respiratory Syndrome Virus Variants That Recently Emerged In The United States, Aspen M. Workman, Timothy P.L. Smith, Fernando A. Osorio, Hiep L.X. Vu

Nebraska Center for Virology: Faculty Publications

A recent outbreak of particularly virulent disease caused by porcine reproductive and respiratory syndrome virus has occurred in swine herds across the United States. We report here the complete genome sequence of eight viral isolates from four Nebraska herds experiencing an outbreak of severe disease in 2016.

Determining The Role Of Poly [Adp-Ribose] Polymerase 1 (Parp-1) In Retroviral Infection, Luis Valdes Rodriguez

Open Access Theses & Dissertations

Possible links between PARP-1 and HIV-1 have been previously reported but the role of this protein during viral infection has remained elusive. Based on the high evolutionary conservation of PARP-1, from Drosophila to humans, we have been able to counteract the difficulties related with the functional redundancy manifested in the PARP family by studying the influence of PARP-1 on the expression of an endogenous retrovirus using the chicken B lymphoblastoid cell line DT40, this cell line exhibits low PARP-1 functional redundancy and is viable after PARP-1 knockout. We have determined that the transcription level of the endogenous retrovirus RAV-1 is …

Domain I Of The 5′ Non-Translated Genomic Region In Coxsackievirus B3 Rna Is Not Required For Productive Replication, L. Jaramillo, S. Smithee, S. Tracy, N. M. Chapman

Nebraska Center for Virology: Faculty Publications

Domain I is a cloverleaf-like secondary structure at the 5′ termini of all enterovirus genomes, comprising part of a cis-acting replication element essential for efficient enteroviral replication. 5′ genomic terminal deletions up to as much as 55% of domain I can occur without lethality following coxsackie B virus infections. We report here that the entire CVB structural domain I can be deleted without lethality.

Reversion To Wildtype Of A Mutated And Nonfunctional Coxsackievirus B3cre(2c), Shane Smithee, Steven Tracy, Nora M. Chapman

Nebraska Center for Virology: Faculty Publications

The cis-acting replication element (CRE) in the 2C protein coding region [CRE(2C)] of enteroviruses (EV) facilitates the addition of two uridine residues (uridylylation) onto the virus-encoded protein VPg inorder for it to serve as the RNA replication primer. We demonstrated that coxsackievirus B3 (CVB3) is replication competent in the absence of a native (uridylylating) CRE(2C) and also demonstrated that lackof a functional CRE(2C) led to generation of 5’ terminal genomic deletions in the CVB3 CRE-knock-out (CVB3-CKO) population. We asked whether reversion of the mutated CRE(2C) occurred, thus permitting sustained replication, and when were 5’ terminal deletions generated during replication. Virions …

Replicating Single-Cycle Adenovirus Vectors Generate Amplified Influenza Vaccine Responses, Catherine M. Crosby, William E. Matchett, Stephanie S. Anguiano-Zarate, Christopher A. Parks, Eric A. Weaver, Larry R. Pease, Richard J. Webby, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Head-to-head comparisons of conventional influenza vaccines with ade- novirus (Ad) gene-based vaccines demonstrated that these viral vectors can mediate more potent protection against influenza virus infection in animal models. In most cases, Ad vaccines are engineered to be replication-defective (RD-Ad) vectors. In contrast, replication-competent Ad (RC-Ad) vaccines are markedly more potent but risk causing adenovirus diseases in vaccine recipients and health care workers. To harness antigen gene replication but avoid production of infectious virions, we de- veloped “single-cycle” adenovirus (SC-Ad) vectors. Previous work demonstrated that SC-Ads amplify transgene expression 100-fold and produce markedly stronger and more persistent immune responses than …