Medical Pathology Commons^™

An Aged Canid With Behavioral Deficits Exhibits Blood And Cerebrospinal Fluid Amyloid Beta Oligomers, Clare Rusbridge, Francisco J. Salguero, Monique Antoinette David, Kiterie M. E. Faller, Jose T. Bras, Rita J. Guerreiro, Angela C. Richard-Londt, Duncan Grainger, Elizabeth Head, Sebastian G. P. Brandner, Brian Summers, John Hardy, Mourad Tayebi

Pharmacology and Nutritional Sciences Faculty Publications

Many of the molecular and pathological features associated with human Alzheimer disease (AD) are mirrored in the naturally occurring age-associated neuropathology in the canine species. In aged dogs with declining learned behavior and memory the severity of cognitive dysfunction parallels the progressive build up and location of Aβ in the brain. The main aim of this work was to study the biological behavior of soluble oligomers isolated from an aged dog with cognitive dysfunction through investigating their interaction with a human cell line and synthetic Aβ peptides. We report that soluble oligomers were specifically detected in the dog's blood and …

A Functional Signature Ontology (Fusion) Screen Detects An Ampk Inhibitor With Selective Toxicity Toward Human Colon Tumor Cells, Binita Das, Beth K. Neilsen, Kurt W. Fisher, Drew Gehring, Youcai Hu, Deanna J. Volle, Hyun Seok Kim, Jamie L. Mccall, David L. Kelly, John B. Macmillian, Michael A. White, Robert E. Lewis

Faculty & Staff Scholarship

AMPK is a serine threonine kinase composed of a heterotrimer of a catalytic, kinase-containing α and regulatory β and γ subunits. Here we show that individual AMPK subunit expression and requirement for survival varies across colon cancer cell lines. While AMPKα1 expression is relatively consistent across colon cancer cell lines, AMPKα1 depletion does not induce cell death. Conversely, AMPKα2 is expressed at variable levels in colon cancer cells. In high expressing SW480 and moderate expressing HCT116 colon cancer cells, siRNA-mediated depletion induces cell death. These data suggest that AMPK kinase inhibition may be a useful component of future therapeutic strategies. …

A Tangled Web: Origins Of Reproductive Parasitism, Joseph J. Gillespie, Timothy P. Driscoll, Victoria I. Verhoeve, Mohammed Sayeedur Rahman, Kevin R. Macaluso

Faculty & Staff Scholarship

While typically a flea parasite and opportunistic human pathogen, the presence of Rickettsia felis (strain LSU-Lb) in the non-blood- feeding, parthenogenetically reproducing booklouse, Liposcelis bostrychophila, provides a system to ascertain factors governing not only host transitions but also obligate reproductive parasitism (RP). Analysis of plasmid pLbAR, unique to R. felis str. LSU-Lb, revealed a toxin–antitoxin module with similar features to prophage-encoded toxin–antitoxin modules utilized by parasitic Wolbachia strains to induce another form of RP, cytoplasmic incompatibility, in their arthropod hosts. Curiously, multiple deubiquitinase and nuclease domains of the large (3,841 aa) pLbAR toxin, as well the entire antitoxin, facilitated the …

Altered Ratio Of T Follicular Helper Cells To T Follicular Regulatory Cells Correlates With Autoreactive Antibody Response In Simian Immunodeficiency Virus–Infected Rhesus Macaques, Wenjin Fan, Andrew James Demers, Yanmin Wan, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

Individuals with chronic HIV-1 infection have an increased prevalence of autoreactive Abs. Many of the isolated HIV broadly neutralizing Abs from these individuals are also autoreactive. However, the underlying mechanism(s) that produce these autoreactive broadly neutralizing Abs remains largely unknown. The highly regulated coordination among B cells, T follicular helper (T_FH) cells, and T follicular regulatory (T_FR) cells in germinal centers (GCs) of peripheral lymphatic tissues (LTs) is essential for defense against pathogens while also restricting autoreactive responses. We hypothesized that an altered ratio of T_FH/T_FR cells in the GC contributes to the …

Mucosal Antibody Responses To Vaccines Targeting Siv Protease Cleavage Sites Or Fulllength Gag And Env Proteins In Mauritian Cynomolgus Macaques, Hongzhao Li, Yan Hai, So-Yon Lim, Nikki Toledo, Jose Crecente-Campo, Dane Schalk, Lin Li, Robert W. Omange, Tamara G. Dacoba, Lewis R. Liu, Mohammad Abul Kashem, Yanmin Wan, Binhua Liang, Qingsheng Li, Eva Rakasz, Nancy Schultz-Darken, Maria J. Alonso, Francis A. Plummer, James B. Whitney, Ma Luo

Nebraska Center for Virology: Faculty Publications

HIV mutates rapidly and infects CD4⁺ T cells, especially when they are activated. A vaccine targeting conserved, essential viral elements while limiting CD4⁺ T cell activation could be effective. Learning from natural immunity observed in a group of highly HIV-1 exposed seronegative Kenyan female sex workers, we are testing a novel candidate HIV vaccine targeting the 12 viral protease cleavage sites (PCSs) (the PCS vaccine), in comparison with a vaccine targeting full-length Gag and Env (the Gag/Env vaccine) in a Mauritian cynomolgus macaque/SIV model. In this study we evaluated these vaccines for induction of mucosal antibodies to SIV …

Sivcpz Closely Related To The Ancestral Hiv-1 Is Less Or Non-Pathogenic To Humans In A Hu-Blt Mouse Model, Zhe Yuan, Guobin Kang, Lance Daharsh, Wenjin Fan, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The HIV-1 pandemic is a consequence of the cross-species transmission of simian immunodeficiency virus in wild chimpanzees (SIVcpz) to humans. Our previous study demonstrated SIVcpz strains that are closely related to the ancestral viruses of HIV-1 groups M (SIVcpzMB897) and N (SIVcpzEK505) and two SIVcpz lineages that are not associated with any known HIV-1 infections in humans (SIVcpzMT145 and SIVcpzBF1167), all can readily infect and robustly replicate in the humanized-BLT mouse model of humans. However, the comparative pathogenicity of different SIVcpz strains remains unknown. Herein, we compared the pathogenicity of the above four SIVcpz strains with HIV-1 using humanized-BLT mice. …

Identification Of Unequally Represented Founder Viruses Among Tissues In Very Early Siv Rectal Transmission, Jian Chen, Yanqin Ren, Lance Daharsh, Lu Liu, Guobin Kang, Qingsheng Li, Qiang Wei, Yanmin Wu, Jianqing Xu

Nebraska Center for Virology: Faculty Publications

Characterizing the transmitted/founder (T/F) viruses of multi-variant SIV infection may shed new light on the understanding of mucosal transmission.We intrarectally inoculated six Chinese rhesus macaques with a single high dose of SIVmac251 (3.1 × 10⁴ TCID₅₀) and obtained 985 full-length env sequences from multiple tissues at 6 and 10 days post-infection by single genome amplification (SGA). All 6 monkeys were infected with a range of 2 to 8 T/F viruses and the dominant variants from the inoculum were still dominant in different tissues from each monkey. Interestingly, our data showed that a cluster of rare T/F viruses …

Analytical Performance Of A Low‐Cost Multiplex Polymerase Chain Reaction Human Papillomavirus Genotyping Assay For Use In Sub‐Saharan Africa, Kandali Samwel, Crispin Kahesa, Julius Mwaiselage, Daniela Gonzalez, John T. West, Charles Wood, Joel Palefsky, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

We have tested a multiplex polymerase chain reaction (PCR) human papillomavirus (HPV) genotyping assay to fill the need for rapid and low‐cost HPV detection in Sub‐ Saharan Africa. This method allows high throughput genotyping and simultaneous detection of 14 high‐risk and two low‐risk HPV types, by PCR amplification of HPV DNAs in a single reaction tube. In this study, we describe stepwise experiments to validate the multiplex HPV PCR assay for determination of HPV genotypes from 104 cervical brush samples from Tanzanian women. Assay performance was evaluated by determination of intra‐laboratory reproducibility, sensitivity, and specificity. Further performance was assessed by …

Discovery Of A Non-Nucleoside Rna Polymerase Inhibitor For Blocking Zika Virus Replication Through In Silico Screening, Aryamav Pattnaik, Nicholas Palermo, Bikash R. Sahoo, Zhe Yuan, Duoyi Hu, Arun S. Annamalai, Hiep L. X. Vu, Ignacio Correas, Pavan Kumar Prathipati, Christopher J. Destache, Qingsheng Li, Fernando A. Osorio, Asit K. Pattnaik, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

Zika virus (ZIKV), an emerging arbovirus, has become a major human health concern globally due to its association with congenital abnormalities and neurological diseases. Licensed vaccines or antivirals against ZIKV are currently unavailable. Here, by employing a structure-based approach targeting the ZIKV RNA-dependent RNA polymerase (RdRp), we conducted in silico screening of a library of 100,000 small molecules and tested the top ten lead compounds for their ability to inhibit the virus replication in cell-based in vitro assays. One compound, 3-chloro-N-[({4-[4-(2-thienylcarbonyl)-1-piperazinyl]phenyl}amino)carbonothioyl]-1-benzothiophene-2-carboxamide (TPB), potently inhibited ZIKV replication at submicromolar concentrations. Molecular docking analysis suggests that …

Non-Naturally Occurring Porcine Reproductive And Respiratory Syndrome Virus (Prrsv) And Methods Of Using, Hiep Lai Xuan Vu, Fernando Osorio, William W. Laegreid, Asit K. Pattnaik, Fangrui Ma

Nebraska Center for Virology: Faculty Publications

A non-naturally occurring porcine reproductive and respiratory syndrome virus (PRRSV) is provided herein, and methods of making and using the non-naturally occurring PRRSV also are provided.

Brain Is A Potential Sanctuary For Subtype C Hiv-1 Irrespective Of Art Treatment Outcome, For Yue Tso, Guobin Kang, Eun Hee Kwon, Peter Julius, Qingsheng Li, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of …

Brain Is A Potential Sanctuary For Subtype C Hiv-1 Irrespective Of Art Treatment Outcome, For Yue Tso, Guobin Kang, Peter Julius, Qingsheng Li, John T. West, Charles Wood

Nebraska Center for Virology: Faculty Publications

Subtype C HIV-1 is responsible for the largest proportion of people living with HIV-1 infection. However, there is limited information about the roles of the brain and its cell types as a potential sanctuary for this subtype and how the sanctuary may be affected by the administration of anti-retroviral therapy (ART). To address this issue, we collected postmortem brain tissues from ART treated HIV-1 infected Zambian individuals who experienced complete viral suppression and those who did not. Tissues from various brain compartments were collected from each individual as frozen and formalin-fixed paraffin embedded brain specimens, for detection and quantification of …

Contribution Of The Gp120 V3 Loop To Envelope Glycoprotein Trimer Stability In Primate Immunodeficiency Viruses, Dane Bowder, Haley Hollingsead, Kate Durst, Duoyi Hu, Wenzhong Wei, Joshua Wiggins, Halima Medjahed, Andrés Finzi, Joseph Sodroski, Shi-Hua Xiang

Nebraska Center for Virology: Faculty Publications

The V3 loop of the human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein (Env) becomes exposed after CD4 binding and contacts the coreceptor to mediate viral entry. Prior to CD4 engagement, a hydrophobic patch located at the tip of the V3 loop stabilizes the non-covalent association of gp120 with the Env trimer of HIV-1 subtype B strains. Here, we show that this conserved hydrophobic patch (amino acid residues 307, 309 and 317) contributes to gp120-trimer association in HIV-1 subtype C, HIV-2 and SIV. Changes that reduced the hydrophobicity of these V3 residues resulted in increased gp120 shedding and …

Ultrastructure Of Meelsvirus: A Nuclear Virus Of Arrow Worms (Phylum Chaetognatha) Producing Giant "Tailed" Virions, George L. Shinn, Brianna L. Bullard

Nebraska Center for Virology: Faculty Publications

Most known giant viruses, i.e., viruses producing giant virions, parasitize amoebae and other unicellular eukaryotes. Although they vary in the level of dependence on host nuclear functions, their virions self-assemble in the host cell's cytoplasm. Here we report the discovery of a new prototype of giant virus infecting epidermal cells of the marine arrow worm Adhesisagitta hispida. Its 1.25 μm-long virions self-assemble and accumulate in the host cell's nucleus. Conventional transmission electron microscopy reveals that the virions have a unique bipartite structure. An ovoid nucleocapsid, situated in a broad "head" end of the virion is surrounded by a thin …

Development Of A Broadly Protective Modified-Live Virus Vaccine Candidate Against Porcine Reproductive And Respiratory Syndrome Virus, Haiyan Sun, Aspen Workman, Fernando A. Osorio, David J. Steffen, Hiep L.X. Vu

Nebraska Center for Virology: Faculty Publications

Modified-live virus (MLV) vaccines are widely used to protect pigs against porcine reproductive and respiratory syndrome virus (PRRSV). However, current MLV vaccines do not confer adequate levels of heterologous protection, presumably due to the substantial genetic diversity of PRRSV isolates circulating in the field. To overcome this genetic variation challenge, we recently generated a synthetic PRRSV strain containing a consensus genomic sequence of PRRSV-2. We demonstrated that our synthetic PRRSV strain confers unprecedented levels of heterologous protection. However, the synthetic PRRSV strain at passage 1 (hereafter designated CON-P1) is highly virulent and therefore, is not suitable to be used as …

Efficacy Of An Adenoviral Vectored Multivalent Centralized Influenza Vaccine, Amy Lingel, Brianna L. Bullard, Eric A. Weaver

Nebraska Center for Virology: Faculty Publications

Mice were immunized with Adenovirus expressing the H1-con, H2-con, H3-con and H5-con HA consensus genes in combination (multivalent) and compared to mice immunized with the traditional 2010–2011 FluZone and FluMist seasonal vaccines. Immunized mice were challenged with 10–100 MLD50 of H1N1, H3N1, H3N2 and H5N1 influenza viruses. The traditional vaccines induced robust levels of HA inhibition (HI) titers, but failed to protect against five different heterologous lethal influenza challenges. Conversely, the multivalent consensus vaccine (1 × 1010 virus particles (vp)/mouse) induced protective HI titers of ≥40 against 8 of 10 influenza viruses that represent a wide degree of divergence within …

Characterization Of Different Molecular Markers For Identification Of Salmonella Enterica Serovar Typhi In Pakistani Population, Faizan Muttiullah, Fida Muhammad Khan, Fakhar-I- Abbas, Sabiha Shamim

Journal of Bioresource Management

Typhoid is caused by Salmonella enterica serovar Typhi that is usually diagnosed by using serologic and immuno-chromatographic techniques in developing counties including Pakistan, which is thought to be an unreliable diagnostic method. For accurate diagnosis we used molecular techniques to amplify 204 bp StyR-36 and 498 bp flagellin gene for the identification of Salmonella enterica serovar Typhi. This study was done on 58 individuals diagnosed positive of typhoid via serologic tests and 50 healthy individuals as a control group. Success rate of amplification for flagellin gene was 77.58% while that for StyR-36 gene was 68.97% showing that flagellin gene primer …

Prevalence Of Kaposi’S Sarcoma-Associated Herpesvirus In Uygur And Han Populations From The Urumqi And Kashgar Regions Of Xinjiang, China, Jun Zheng, Yang Yang, Meng Cui, Zhan-Jun Shu, Li-Li Han, Zhen-Qiu Liu, Charles Wood, Tiejun Zhang, Yan Zeng

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) is the infectious etiologic agent associated with Kaposi’s sarcoma (KS), primary effusion lymphoma, and multicentric Castleman disease. It has been shown that high KSHV prevalence and high incidence of both classic KS and AIDSassociated KS are found mostly among people of Uygur ethnicity in Xinjiang, while people of Han ethnicity in Xinjiang have a higher KSHV seroprevalence than those of other Han populations in mainland China. However, it is still unclear why there is such geographical and population variation in KSHV distribution in China. In this work, we focused on the populations in the Kashgar region …

Relative Contribution Of Porcine Reproductive And Respiratory Syndrome Virus Open Reading Frames 2–4 To The Induction Of Protective Immunity, Katherine Kimpston-Burkgren, Ignacio Correas, Fernando A. Osorio, David Steffen, Asit K. Pattnaik, Ying Fang, Hiep L. X. Vu

Nebraska Center for Virology: Faculty Publications

The minor glycoproteins (GPs) of PRRSV, GP2, GP3, and GP4, form a heterotrimer that is required for viral infectivity, presumably due to its interaction with the key cellular receptor CD163. These 3 GPs are encoded by open reading frames (ORFs) 2a, 3, and 4 (herein referred to as ORFs 2–4), respectively. The goal of this study was to investigate the immunogenicity of the PRRSV-2 minor GPs. Through the use of reverse genetics, a chimeric virus (designated SDFL24) was constructed by replacing ORFs 2–4 of the PRRSV-1 strain SD01-08 with the corresponding genes of the PRRSV-2 strain FL12. While the parental …

Towards A Personalized Cancer Gene Therapy: A Case Of Clear Cell Renal Cell Carcinoma, Dumitru Iacobas, Sanda Iacobas

NYMC Faculty Publications

No abstract provided.

Seroprevalence Of Antibodies Against Kaposi's Sarcoma-Associated Herpesvirus Among Hiv-Negative People In China, Tiejun Zhang, Zhenqiu Liu, Jun Wang, Veenu Minhas, Charles Wood, Gary M. Clifford, Na He, Silvia Franceschi

Nebraska Center for Virology: Faculty Publications

Background: Little information on the prevalence of Kaposi’s sarcoma associated herpesvirus (KSHV) among HIV-negative individuals is available from Asia.

Methods: In the present study, we report findings from a new survey of KSHV in 983 HIV-negative male migrants from Shanghai and their combination with previous similar surveys of 600 female migrants, 600 female sex-workers (FSW), 1336 sexually transmitted infection (STI) clinic male patients, 439 intravenous drug-users (IVDU), and 226 men having sex with men (MSM) from China. KSHV-specific antibodies against latent and lytic antigens were assessed using Sf9 and BC3 monoclonal immunofluorescence assay. Age-adjusted prevalence ratios (PR) and 95% confidence …

The Transcriptional Regulation Of The Human Angiotensinogen Gene After High-Fat Diet Is Haplotype-Dependent: Novel Insights Into The Gene-Regulatory Networks And Implications For Human Hypertension, A Rana, S Jain, N Puri, M Kaw, N Sirianni, D Eren, Brahma Mopidevi, Anand Kumar

NYMC Faculty Publications

Single nucleotide polymorphisms (SNPs) in the human angiotensinogen (hAGT) gene may modulate its transcription and affect the regulation of blood pressure via activation of the renin-angiotensin aldosterone system (RAAS). In this regard, we have identified polymorphisms in the 2.5 Kb promoter of the hAGT gene that form two haplotype (Hap) blocks: -6A/G (-1670A/G, -1562C/T, -1561T/C) and -217A/G (-532T/C, -793A/G, -1074T/C & -1178G/A). hAGT gene with Hap -6A/-217A (Hap I) is associated with increased blood pressure whereas, Hap -6G/-217G (Hap II) is associated with normal blood pressure in human subjects. Since RAAS over activity contributes to hypertension in obesity, we have …

Lysine Residues Of Interferon Regulatory Factor 7 Affect The Replication And Transcription Activatormediated Lytic Replication Of Kaposi’S Sarcomaassociated Herpesvirus/Human Herpesvirus 8, Tianzheng Zhang, Ying Wang, Li Zhang, Bin Liu, Jinhui Xie, Charles Wood, Jinzhong Wang

Nebraska Center for Virology: Faculty Publications

Kaposi’s sarcoma-associated herpesvirus (KSHV) infection goes through latent and lytic phases, which are controlled by the viral replication and transcription activator (RTA). Upon KSHV infection, the host responds by suppressing RTA-activated lytic gene expression through interferon regulatory factor 7 (IRF-7), a key regulator of host innate immune response. Lysine residues are potential sites for post-translational modification of IRF-7, and were suggested to be critical for its activity. In this study, we analysed the 15 lysine residues for their effects on IRF-7 function by site-directed mutagenesis. We found that some mutations affect the ability of IRF-7 to activate interferon (IFN)-a1 and …

Exploring Therapeutic Approaches For Marfan Syndrome Associated Aortic Aneurysm, Mitra Esfandiarei

Science Seminar Series

Esfandiearei will be discussing her research on understanding the underlying mechanisms contributing to the progression of aortic aneurysm in Marfan syndrome and the protective effects that exercise may have on the disease process in both laboratory animal models and human patients. Her research has been supported by the Canadian Institutes of Health Research (CIHR), Rare Diseases Foundation, and the Marfan Foundation.

Coccolithoviruses: A Review Of Cross-Kingdom Genomic Thievery And Metabolic Thuggery, Jozef I. Nissimov, António Pagarete, Fangrui Ma, Sean Cody, David D. Dunigan, Susan A. Kimmance, Michael J. Allen

Nebraska Center for Virology: Faculty Publications

Coccolithoviruses (Phycodnaviridae) infect and lyse the most ubiquitous and successful coccolithophorid in modern oceans, Emiliania huxleyi. So far, the genomes of 13 of these giant lytic viruses (i.e., Emiliania huxleyi viruses—EhVs) have been sequenced, assembled, and annotated. Here, we performed an in-depth comparison of their genomes to try and contextualize the ecological and evolutionary traits of these viruses. The genomes of these EhVs have from 444 to 548 coding sequences (CDSs). Presence/absence analysis of CDSs identified putative genes with particular ecological significance, namely sialidase, phosphate permease, and sphingolipid biosynthesis. The viruses clustered into distinct clades, based on their DNA polymerase …

Diagnosis Of Lchad/Tfp Deficiency In An At Risk Newborn Using Umbilical Cord Blood Acylcarnitine Analysis, Donna Raval, Kristina Cusmano-Ozog, Omar Ayyub, Callie Jenevein, Laura Kofman, Brendan Lanpher, Natalie Hauser, Debra Regier

Pathology Faculty Publications

Trifunctional protein deficiency/Long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHAD/TFP) deficiency is a disorder of fatty acid oxidation and ketogenesis. Severe neonatal lactic acidosis, cardiomyopathy, and hepatic dysfunction are caused by the accumulation of toxic long-chain acylcarnitines. The feasibility of umbilical cord blood use in screening for acylcarnitine analysis and free carnitine has been hypothesized but not reported in LCHAD/TFP neonates.

We present a 4 week old female who was at risk of inheriting LCHAD/TFP deficiency and was diagnosed at the time of delivery using umbilical cord blood. Umbilical cord blood was collected at delivery and sent for acylcarnitine analysis. Treatment was started …

Distinct Transcriptome Profiles Of Gag-Specific Cd8+ T Cells Temporally Correlated With The Protection Elicited By Sivδnef Live Attenuated Vaccine, Wuxun Lu, Yanmin Wu, Fangrui Ma, R. Paul Johnson, Qingsheng Li

Nebraska Center for Virology: Faculty Publications

The live attenuated vaccine (LAV) SIVmac239Δnef (SIVΔnef) confers the best protection among all the vaccine modalities tested in rhesus macaque model of HIV-1 infection. This vaccine has a unique feature of time-dependent protection: macaques are not protected at 3±5 weeks post vaccination (WPV), whereas immune protection emerges between 15 and 20 WPV. Although the exact mechanisms of the time-dependent protection remain incompletely understood, studies suggested that both cellular and humoral immunities contribute to this time-dependent protection. To further elucidate the mechanisms of protection induced by SIVΔnef, we longitudinally compared the global gene expression profiles of SIV Gag-CM9+ CD8+ (Gag-specific CD8+) …

Chloroviruses Have A Sweet Tooth, James L. Van Etten, Irina V. Agarkova, David D. Dunigan, Michela Tonetti, Cristina De Castro, Garry A. Duncan

Nebraska Center for Virology: Faculty Publications

Chloroviruses are large double-stranded DNA (dsDNA) viruses that infect certain isolates of chlorella-like green algae. They contain up to approximately 400 protein-encoding genes and 16 transfer RNA (tRNA) genes. This review summarizes the unexpected finding that many of the chlorovirus genes encode proteins involved in manipulating carbohydrates. These include enzymes involved in making extracellular polysaccharides, such as hyaluronan and chitin, enzymes that make nucleotide sugars, such as GDP-L-fucose and GDP-D-rhamnose and enzymes involved in the synthesis of glycans attached to the virus major capsid proteins. This latter process differs from that of all other glycoprotein containing viruses that traditionally use …

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 …

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 …