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Full-Text Articles in Virology

Biology And Ecology Of Aedes (Stegomyia) Aegypti In The Northern Chihuahuan Desert, Adam Joseph Vera Dec 2022

Biology And Ecology Of Aedes (Stegomyia) Aegypti In The Northern Chihuahuan Desert, Adam Joseph Vera

Open Access Theses & Dissertations

Aedes aegypti is a medically important mosquito species that transmits multiple arboviruses, including dengue, chikungunya, Zika, and yellow fever. This mosquito species has expanded its geographical range into expanded into the Northern Chihuahuan Desert to further increase the risk of infection by these viruses in naïve human populations. Although Ae. aegypti is abundant along the U.S.â??Mexico border, the biology and ecology of this mosquito species in this temperate/arid climate region is not understood. The objective of this study was to understand the environmental factors that influence the invasive species of Ae. aegypti abundance, breeding habitat selection, host feeding behavior, and …


Identifying Essential Viral Genes Through Genomic Engineering, Amber Carroll Jan 2020

Identifying Essential Viral Genes Through Genomic Engineering, Amber Carroll

Mahurin Honors College Capstone Experience/Thesis Projects

Bacteria developed resistance to penicillin a mere four years after the groundbreaking antibiotic was first mass produced (Casadevall, 2010). Since then, the development of antibiotic-resistant bacteria has steadily risen, causing millions of difficult to treat infections annually. The challenge is to identify ways to combat these menacing microbes. Bacteriophages are viruses that infect bacteria and can potentially be used to eliminate deadly antibiotic-resistant bacteria. The number of sequenced bacteriophage genomes has increased tremendously over the past 10 years, but little is known about the function of most bacteriophage genes. The purpose of this study was to expand our understanding of …


Genetic Diversity Of Mycobacteriophages And The Unique Abilities Of Cluster K, Shea A. Morris Jun 2017

Genetic Diversity Of Mycobacteriophages And The Unique Abilities Of Cluster K, Shea A. Morris

The Corinthian

Mycobacteriophage are a diverse set of viruses that infect a broad host range of mycobacterium. Genome analysis of this phage group reveals its diversity and provides evidence that they have experienced substantial horizontal gene transfer Collectively they have a large range of host bacteria they can infect, although each viral type may have a limited host range. However, this range is easily expanded and constantly changing in nature by mutation within and between virus types. These phages can lytically destroy their host mycobacteria, and it is this viral ability that have many mycobacteriophage researchers excited about the potential that phage …


Role Of The Dna Sensor Sting In Protection From Lethal Infection Following Corneal And Intracerebral Challenge With Herpes Simplex Virus 1, Zachary M. Parker, Aisling A. Murphy, David. A. Leib Aug 2015

Role Of The Dna Sensor Sting In Protection From Lethal Infection Following Corneal And Intracerebral Challenge With Herpes Simplex Virus 1, Zachary M. Parker, Aisling A. Murphy, David. A. Leib

Dartmouth Scholarship

STING is a protein in the cytosolic DNA and cyclic dinucleotide sensor pathway that is critical for the initiation of innate responses to infection by various pathogens. Consistent with this, herpes simplex virus 1 (HSV-1) causes invariable and rapid lethality in STING-deficient (STING(-/-)) mice following intravenous (i.v.) infection. In this study, using real-time bioluminescence imaging and virological assays, as expected, we demonstrated that STING(-/-) mice support greater replication and spread in ocular tissues and the nervous system. In contrast, they did not succumb to challenge via the corneal route even with high titers of a virus that was routinely lethal …


Selective Involvement Of The Checkpoint Regulator Vista In Suppression Of B-Cell, But Not T-Cell, Responsiveness By Monocytic Myeloid-Derived Suppressor Cells From Mice Infected With An Immunodeficiency-Causing Retrovirus, Kathy A. Green, Li Wang, Randolph J. Noelle, William R. Green Jul 2015

Selective Involvement Of The Checkpoint Regulator Vista In Suppression Of B-Cell, But Not T-Cell, Responsiveness By Monocytic Myeloid-Derived Suppressor Cells From Mice Infected With An Immunodeficiency-Causing Retrovirus, Kathy A. Green, Li Wang, Randolph J. Noelle, William R. Green

Dartmouth Scholarship

Inhibition of T-cell responses in tumor microenvironments by myeloid-derived suppressor cells (MDSCs) is widely accepted. We demonstrated augmentation of monocytic MDSCs whose suppression of not only T-cell, but also B-cell, responsiveness paralleled the immunodeficiency during LP-BM5 retrovirus infection. MDSCs inhibited T cells by inducible nitric oxide synthase (iNOS)/nitric oxide (NO), but uniquely, inhibition of B cells was ~50% dependent each on iNOS/NO and the MDSC-expressed negative-checkpoint regulator VISTA. Blockade with a combination of iNOS/NO and VISTA caused additive or synergistic abrogation of MDSC-mediated suppression of B-cell responsiveness.


Mcl1 Enhances The Survival Of Cd8+ Memory T Cells After Viral Infection, Jingang Gui, Zhuting Hu, Ching-Yi Tsai, Tian Ma, Yan Song, Amanda Morales, Li-Hao Huang, Ethan Dmitrovsky, Ruth Craig, Edward Usherwood Jan 2015

Mcl1 Enhances The Survival Of Cd8+ Memory T Cells After Viral Infection, Jingang Gui, Zhuting Hu, Ching-Yi Tsai, Tian Ma, Yan Song, Amanda Morales, Li-Hao Huang, Ethan Dmitrovsky, Ruth Craig, Edward Usherwood

Dartmouth Scholarship

Viral infection results in the generation of massive numbers of activated effector CD8+ T cells that recognize viral components. Most of these are short-lived effector T cells (SLECs) that die after clearance of the virus. However, a small proportion of this population survives and forms antigen-specific memory precursor effector cells (MPECs), which ultimately develop into memory cells. These can participate in a recall response upon reexposure to antigen even at protracted times postinfection. Here, antiapoptotic myeloid cell leukemia 1 (MCL1) was found to prolong survival upon T cell stimulation, and mice expressing human MCL1 as a transgene exhibited a skewing …


Host Species Restriction Of Middle East Respiratory Syndrome Coronavirus Through Its Receptor, Dipeptidyl Peptidase 4, Neeltje Van Doremalen, Kerri L. Miazgowicz, Shauna Milne-Price, Trenton Bushmaker, Shelly Robertson, Dana Scott, Joerg Kinne, Jason S. Mclellan Jun 2014

Host Species Restriction Of Middle East Respiratory Syndrome Coronavirus Through Its Receptor, Dipeptidyl Peptidase 4, Neeltje Van Doremalen, Kerri L. Miazgowicz, Shauna Milne-Price, Trenton Bushmaker, Shelly Robertson, Dana Scott, Joerg Kinne, Jason S. Mclellan

Dartmouth Scholarship

Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012. Recently, the MERS-CoV receptor dipeptidyl peptidase 4 (DPP4) was identified and the specific interaction of the receptor-binding domain (RBD) of MERS-CoV spike protein and DPP4 was determined by crystallography. Animal studies identified rhesus macaques but not hamsters, ferrets, or mice to be susceptible for MERS-CoV. Here, we investigated the role of DPP4 in this observed species tropism. Cell lines of human and nonhuman primate origin were permissive of MERS-CoV, whereas hamster, ferret, or mouse cell lines were not, despite the presence of DPP4. Expression of human DPP4 in nonsusceptible BHK and …


Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman Dec 2013

Divergent Antibody Subclass And Specificity Profiles But Not Protective Hla-B Alleles Are Associated With Variable Antibody Effector Function Among Hiv-1 Controllers, Jennifer I. Lai, Anna F. Licht, Anne-Sophie Dugast, Todd Suscovich, Ickwon Choi, Chris Bailey-Kellogg, Galit Alter, Margaret E. Ackerman

Dartmouth Scholarship

Understanding the coordination between humoral and cellular immune responses may be the key to developing protective vaccines, and because genetic studies of long-term HIV-1 nonprogressors have associated specific HLA-B alleles with spontaneous control of viral replication, this subject group presents an opportunity to investigate relationships between arms of the adaptive immune system. Given evidence suggesting that cellular immunity may play a role in viral suppression, we sought to determine whether and how the humoral immune response might vary among controllers. Significantly, Fc-mediated antibody effector functions have likewise been associated with durable viral control. In this study, we compared the effector …


Use Of Irf-3 And/Or Irf-7 Knockout Mice To Study Viral Pathogenesis: Lessons From A Murine Retrovirus-Induced Aids Model, Megan A. O'Connor, William R. Green Dec 2013

Use Of Irf-3 And/Or Irf-7 Knockout Mice To Study Viral Pathogenesis: Lessons From A Murine Retrovirus-Induced Aids Model, Megan A. O'Connor, William R. Green

Dartmouth Scholarship

Interferon regulatory factor (IRF) regulation of the type I interferon response has not been extensively explored in murine retroviral infections. IRF-3(-/-) and select IRF-3/7(-/-) mice were resistant to LP-BM5-induced pathogenesis. However, further analyses strongly suggested that resistance could be attributed to strain 129-specific contamination of the known retrovirus resistance gene Fv1. Therefore, caution should be taken when interpreting phenotypes observed in these knockout mice, as strain 129-derived genetic polymorphisms may explain observed differences.


In Vitro Characterization Of Avian Influenza Virus Isolates With A Truncated Ns1 Gene Segment, Aaron Dick May 2013

In Vitro Characterization Of Avian Influenza Virus Isolates With A Truncated Ns1 Gene Segment, Aaron Dick

Honors Scholar Theses

Avian Influenza Virus represents a significant threat to the world poultry population, and is a potential threat to humans due to the possibility of cross-species AIV infection. Our approach is to characterize a number of avian virus populations with respect to their content of biologically active particles that include hemagglutinating particles (HAP), plaque forming particles (PFP), interferon inducing particles (IFP), interferon induction-suppressing particles (ISP), defective-interfering particles (DIP), cell-killing particles (CKP) and non-infectious cell killing particles (niCKP) using unique in vitro assays developed for avian influenza virus in the Marcus-Sekellick Laboratory. Specifically, we will use a strain of Avian influenza virus, …


Inhibition Of The Host Translation Shutoff Response By Herpes Simplex Virus 1 Triggers Nuclear Envelope-Derived Autophagy, Kerstin Radtke, Luc English, Christiane Rondeau, David Leib Jan 2013

Inhibition Of The Host Translation Shutoff Response By Herpes Simplex Virus 1 Triggers Nuclear Envelope-Derived Autophagy, Kerstin Radtke, Luc English, Christiane Rondeau, David Leib

Dartmouth Scholarship

Macroautophagy is a cellular pathway that degrades intracellular pathogens and contributes to antigen presentation. Herpes simplex virus 1 (HSV-1) infection triggers both macroautophagy and an additional form of autophagy that uses the nuclear envelope as a source of membrane. The present study constitutes the first in-depth analysis of nuclear envelope-derived autophagy (NEDA). We established LC3a as a marker that allowed us to distinguish between NEDA and macroautophagy in both immunofluorescence and flow cytometry. NEDA was observed in many different cell types, indicating that it is a general response to HSV-1 infection. This autophagic pathway is known to depend on the …


Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib May 2012

Corneal Replication Is An Interferon Response-Independent Bottleneck For Virulence Of Herpes Simplex Virus 1 In The Absence Of Virion Host Shutoff, Tracy J. Pasieka, Vineet D. Menachery, Pamela C. Rosato, David A. Leib

Dartmouth Scholarship

Herpes simplex viruses lacking the virion host shutoff function (Δvhs) are avirulent and hypersensitive to type I and type II interferon (IFN). In this study, we demonstrate that even in the absence of IFN responses in AG129 (IFN-αβγR−/−) mice, Δvhs remains highly attenuated via corneal infection but is fully virulent via intracranial infection. The data demonstrate that the interferon-independent inherent replication defect of Δvhs has a significant impact upon peripheral replication and neuroinvasion.


Cd80 And Cd86 Control Antiviral Cd8+ T-Cell Function And Immune Surveillance Of Murine Gammaherpesvirus 68, Shinichiro Fuse, Joshua J. Obar, Sarah Bellfy, Erica K. Leung, Weijun Zhang, Edward J. Usherwood Sep 2006

Cd80 And Cd86 Control Antiviral Cd8+ T-Cell Function And Immune Surveillance Of Murine Gammaherpesvirus 68, Shinichiro Fuse, Joshua J. Obar, Sarah Bellfy, Erica K. Leung, Weijun Zhang, Edward J. Usherwood

Dartmouth Scholarship

The interactions between CD80 and CD86 on antigen-presenting cells and CD28 on T cells serve as an important costimulatory signal in the activation of T cells. Although the simplistic two-signal hypothesis has been challenged in recent years by the identification of different costimulators, this classical pathway has been shown to significantly impact antiviral humoral and cellular immune responses. How the CD80/CD86-CD28 pathway affects the control of chronic or latent infections has been less well characterized. In this study, we investigated its role in antiviral immune responses against murine gammaherpesvirus 68 (MHV-68) and immune surveillance using CD80/CD86−/− mice. In the …


Gammaherpesvirus Persistence Alters Key Cd8 T-Cell Memory Characteristics And Enhances Antiviral Protection, Joshua J. Obar, Shinichiro Fuse, Erica K. Leung, Sarah C. Bellfy, Edward J. Usherwood Sep 2006

Gammaherpesvirus Persistence Alters Key Cd8 T-Cell Memory Characteristics And Enhances Antiviral Protection, Joshua J. Obar, Shinichiro Fuse, Erica K. Leung, Sarah C. Bellfy, Edward J. Usherwood

Dartmouth Scholarship

In herpesvirus infections, the virus persists for life but is contained through T-cell-mediated immune surveillance. How this immune surveillance operates is poorly understood. Recent studies of other persistent infections have indicated that virus persistence is associated with functional deficits in the CD8(+) T-cell response. To test whether this is the case in a herpesvirus infection, we used a mutant murine gammaherpesvirus that is defective in its ability to persist in the host. By comparing the immune response to this virus with a revertant virus that can persist, we were able to dissect the changes in the antiviral CD8(+) T-cell response …


Transformation Of A Continuous Rat Embryo Fibroblast Cell Line Requires Three Separate Domains Of Simian Virus 40 Large T Antigen., Jiyue Zhu, Philip W. Rice, Lisa Gorsch, Marina Abate, Charles N. Cole May 1992

Transformation Of A Continuous Rat Embryo Fibroblast Cell Line Requires Three Separate Domains Of Simian Virus 40 Large T Antigen., Jiyue Zhu, Philip W. Rice, Lisa Gorsch, Marina Abate, Charles N. Cole

Dartmouth Scholarship

Mouse C3H 10T1/2 cells and the established rat embryo fibroblast cell line REF-52 are two cell lines widely used in studies of viral transformation. Studies have shown that transformation of 10T1/2 cells requires only the amino-terminal 121 amino acids of simian virus 40 (SV40) large T antigen, while transformation of REF-52 cells requires considerably more of large T antigen, extending from near the N terminus to beyond residue 600. The ability of a large set of linker insertion, small deletion, and point mutants of SV40 T antigen to transform these two cell lines and to bind p105Rb was determined. Transformation …


The Growth Of Simian Virus 40 (Sv40) Host Range/Adenovirus Helper Function Mutants In An African Green Monkey Cell Line That Constitutively Expresses The Sv40 Agnoprotein., Terryl P. Stacy, Michele Chamberlain, Susan Carswell, Charles N. Cole Jul 1990

The Growth Of Simian Virus 40 (Sv40) Host Range/Adenovirus Helper Function Mutants In An African Green Monkey Cell Line That Constitutively Expresses The Sv40 Agnoprotein., Terryl P. Stacy, Michele Chamberlain, Susan Carswell, Charles N. Cole

Dartmouth Scholarship

The simian virus 40 T-antigen carboxy-terminal mutants, dlA2459 and dlA2475, are cell line and temperature dependent for growth and plaque formation in monkey kidney cells. Although these mutants did form plaques on BSC-1 cells at 37 degrees C, they were about fivefold less efficient for plaque formation than wild-type simian virus 40. These mutants did not grow in CV-1 cells and did not synthesize agnoprotein in those cells. CV-1 cells which constitutively express the agnoprotein were permissive for mutant plaque formation. However, late mRNAs, virion proteins, and progeny virion yields did not accumulate to wild-type levels during mutant infection of …


Mechanism Of Escape Of Endogenous Murine Leukemia Virus Emv-14 From Recognition By Anti-Akr/Gross Virus Cytolytic T Lymphocytes., Hillary D. White, Michael D. Robbins, William R. Green Jun 1990

Mechanism Of Escape Of Endogenous Murine Leukemia Virus Emv-14 From Recognition By Anti-Akr/Gross Virus Cytolytic T Lymphocytes., Hillary D. White, Michael D. Robbins, William R. Green

Dartmouth Scholarship

It was previously shown that spleen cells from endogenous ecotropic murine leukemia virus emv-14+ AKXL-5 mice fail to stimulate an anti-AKR/Gross virus cytolytic T-lymphocyte (CTL) response in a mixed lymphocyte culture with primed C57BL/6 responder spleen cells, whereas spleen cells from AKXL strains carrying the very similar emv-11 provirus do stimulate a response (Green and Graziano, Immunogenetics 23:106-110, 1986). We wished to determine whether the lack of response with AKXL-5 spleen cells was at the level of recognition between effector cell and target cell and whether the relevant mutation was within the emv-14 provirus. It is shown here that EMV-negative …


Absence Of A Structural Basis For Intracellular Recognition And Differential Localization Of Nuclear And Plasma Membrane-Associated Forms Of Simian Virus 40 Large Tumor Antigen., Donald L. Jarvis, Charles N. Cole, Janet S. Butel Mar 1986

Absence Of A Structural Basis For Intracellular Recognition And Differential Localization Of Nuclear And Plasma Membrane-Associated Forms Of Simian Virus 40 Large Tumor Antigen., Donald L. Jarvis, Charles N. Cole, Janet S. Butel

Dartmouth Scholarship

The simian virus 40 large tumor antigen (T-ag) is found in both the nuclei (nT-ag) and plasma membranes (mT-ag) of simian virus 40-infected or -transformed cells. It is not known how newly synthesized T-ag molecules are recognized, sorted, and transported to their ultimate subcellular destinations. One possibility is that these events depend upon structural differences between nT-ag and mT-ag. To test this possibility, we compared the structures of nT-ag and mT-ag from simian virus 40-infected cells. No differences between the two forms of T-ag were detected by migration in polyacrylamide gels, by Staphylococcus aureus V8 partial proteolytic mapping of methionine- …


Two Separable Functional Domains Of Simian Virus 40 Large T Antigen: Carboxyl-Terminal Region Of Simian Virus 40 Large T Antigen Is Required For Efficient Capsid Protein Synthesis., Joanne Tornow, Maryellen Polvino-Bodnar, George Santangelo, Charles N. Cole Feb 1985

Two Separable Functional Domains Of Simian Virus 40 Large T Antigen: Carboxyl-Terminal Region Of Simian Virus 40 Large T Antigen Is Required For Efficient Capsid Protein Synthesis., Joanne Tornow, Maryellen Polvino-Bodnar, George Santangelo, Charles N. Cole

Dartmouth Scholarship

The carboxyl-terminal portion of simian virus 40 large T antigen is essential for productive infection of CV-1 and CV-1p green monkey kidney cells. Mutant dlA2459, lacking 14 base pairs at 0.193 map units, was positive for viral DNA replication, but unable to form plaques in CV-1p cells (J. Tornow and C.N. Cole, J. Virol. 47:487-494, 1983). In this report, the defect of dlA2459 is further defined. Simian virus 40 late mRNAs were transcribed, polyadenylated, spliced, and transported in dlA2459-infected cells, but the level of capsid proteins produced in infected CV-1 green monkey kidney cells was extremely low. dlA2459 large T …