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Yersinia Pestis Virulence Factor Yopm Undermines The Function Of Distinct Ccr2+Gr1+ Cells In Spleen And Liver During Systemic Plague, Zhan Ye

University of Kentucky Doctoral Dissertations

Yersinia pestis, the infective agent of bubonic and pneumonic plague, is classified as a category A agent of bioterrorism. YopM, a protein toxin of Y. pestis, is necessary for full virulence in a systemic plague mouse model with ambient-temperature grown bacteria. We used this model to identify the cells undermined by YopM. Natural killer (NK) cells were previously reported to be lost in spleen and blood in a YopM-associated way; however, NK cell depletion was found not to occur in liver, and ablation of NK cells had no effect on bacterial growth, indicating that NK cells are redundant …

Antimicrobial Potential Of Selected Actinomycetes Isolated From The Marine Ecosystem., Nur Rahimatul Hayati Abdul Rahman

Student Works (2010-2019)

Actinomycetes are widespread in marine ecosystem. They are of interest in research field as they are capable to produce bioactive secondary metabolites which can be developed into useful pharmaceutical products. An example of the product is antibiotics which can be used to treat infectious diseases. The potential of antibacterial and antifungal activity of eleven marine derived actinomycetes from the genus Streptomyces were studied. They were tested against bacteria Enterobacter faecalis, Staphylococcus aureus, Bacillus subtilis, Pleisiomonas shigelloides and Pseudomonas aeruginosa and fungi Candida parapsilosis and Candida albicans. Primary screening by the cross streak method and secondary screening by diffusion using paper …

Immunomodulatory Effect Of Host And Fungal Eicosanoids During Host-Pathogen Interactions With Candida Albicans, Gitanjali Kundu

Wayne State University Dissertations

Candida albicans, an opportunistic fungal pathogen, poses a significant clinical threat to immunocompromised patients. Diseases associated with this fungus ranges from superficial mucosal infection to life-threatening systemic candidiasis. The mechanisms by which Candida persists at mucosal surfaces in the face of an adaptive response are unclear. Candida produces immunomodulatory oxylipins that cross-react functionally with host eicosanoids, which are considered to play important role in regulating innate and adaptive immune responses. Our objective was to characterize the role of prostaglandins produced by the host and this fungus during host pathogen interactions, both in vitro with dendritic cells (DCs) and macrophages, and …

Detection And Molecular Characterisation Of Rotavirus, Adenovirus And Bocavirus Circulating In Southern Ireland, Olivia Cashman

Theses

This study reports the detection and molecular characterisation of group A rotavirus circulating in the south of Ireland in both the bovine and human population. Characterisation of the group A rotavirus was carried out through the extraction of viral nucleic acid in faecal specimens collected from hospitals in the Cork and Waterford area and Cork regional veterinary laboratory from 2006-2009. Other gastroenteritis viruses characterised during this study include adenovirus type 41, and the newly identified gastrointestinal virus, human bocavirus, which was identified for the first time in Ireland during this study. The human bocaviruses identified in children in the south …

Phage Lysins - Structure, Genetics And Applications, Jennifer Garry

Theses

Antibiotics are of the utmost importance in the fight against pathogenic bacteria, however, in recent years there has been a continual increase in the development of antibiotic resistance among bacteria. As a result it has become essential to develop new technologies to combat these pathogens. One such technology is the application of phage lysins as antimicrobial agents against pathogenic infections. A promising phage lysin is LysK, a 495 amino-acid protein derived from Staphylococcal Phage K. LysK can lyse a wide range of staphylococcal species including MRSA. It is also capable of killing both live and dead cells increasing its potential …

Isolation And Molecular Characterization Of Mycobacterium Avium Subsp. Paratuberculosis In Ireland, Pierre Emmanuel Douarre

Theses

MAP is a proven animal pathogen causing Johne's disease, one of the most widespread and economically important diseases of ruminants. Since 1992 and the opening of the European market, the prevalence of MAP in Ireland has increased considerably. Improvements in diagnostic strategies for Ireland and elsewhere are urgently required. MAP infects a wide host range and has emerged as a potential threat to human health and has been associated with Crohn's disease. The control of paratuberculosis infection requires a better understanding of the genetic diversity of the pathogen. The objective of this study was to isolate and characterize this enteric …

Detection And Molecular Characterization Of Canine Enteric Viruses In Southern Ireland., Susan Mcelligott

Theses

Enteric viruses, such as canine parvovirus (CPV) and canine coronavirus (CCoV), are a major cause of gastroenteritis in dogs. More serious clinical symptoms occur in young pups, or when both of these viruses infect an animal simultaneously. Caliciviruses and rotaviruses can also cause gastroenteritis in dogs, but these viruses, while causing significant problems in other animal species and humans, are considered to be less significant pathogens of canines. However, on occasion, these viruses have been reported to produce severe clinical symptoms such as vomiting, haemorrhagic enteritis and severe dehydration.

Many viral vaccines for canines are formulated using old vaccine viral …

The Im-9 Cell Line: A Model For Evaluating Tcdd-Induced Modulation Of The Polymorphic Human Hs1,2 Enhancer Within The 3' Immunoglobulin Heavy Chain Regulatory Region, Ruth C. Chambers-Turner

Browse all Theses and Dissertations

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a disrupter, of B-cell differentiation, induces binding of the aryl hydrocarbon receptor (AhR) nuclear complex to dioxin responsive elements (DRE) within the mouse immunoglobulin heavy chain regulatory region (3'IgHRR), and produces a marked inhibition of 3'IgHRR activation, IgH expression, and antibody secretion in a well-characterized mouse B-cell line (CH12.LX). The mouse 3'IgHRR consists of at least four enhancers (hs3a; hs1,2; hs3b; hs4), and is highly homologous with the three enhancers (hs3; hs1,2; hs4) of the human 3'IgHRR. A polymorphism of the human hs1,2 enhancer (resulting in varying numbers of tandem repeats containing a DRE and κB site) has …

Rev Interacts With Tubulin Heterodimers To Cause Cell Cycle Defects, Poornima Kotha Lakshmi Narayan

Browse all Theses and Dissertations

Rev is a regulatory protein that plays an important role in the replication of HIV virus by post-transcriptionally promoting expression of viral proteins late in infection. Rev expression also slows cell growth, leads to an accumulation of cells in G2/M specifically before the spindle checkpoint, and can produce changes in ploidy. Because Rev is capable of depolymerizing microtubules (MTs) in vitro, possibly by a mechanism shared with Kinesin-13 proteins, themselves potent cellular MT depolymerases, I tested the hypothesis that these cellular defects were due to an interaction between Rev and tubulin.

To this end, Rev and select Rev mutants defective …

Primary Gamma-Herpesviral Infection In Zambian Children, Veenu Minhas, Brad P. Brayfield, Kay L. Crabtree, Chipepo Kankasa, Charles D. Mitchell, Charles Wood

Nebraska Center for Virology: Faculty Publications

Background: HHV-8 is closely related to Epstein-Barr virus (EBV), but the clinical presentations of these two infections in early childhood are not well understood. Also, it is not known whether infection by one virus correlates with another. Here, we compare the natural history of infection by these two viruses along with the clinical manifestations and risk factors that are associated with early childhood infection in Zambia, which is an endemic area for HHV-8.

Methods: This study was conducted in a cohort of 12 month old Zambian children (N = 677). Data on socio-economic status and a wide range …

Topological Layers In The Hiv-1 Gp120 Inner Domain Regulate Gp41 Interaction And Cd4-Triggered Conformational Transitions, Andrés Finzi, Shi-Hua Xiang, Beatriz Pacheco, Dana-Farber Cancer Institute Wang, Jessica Haight, Aemro Kassa, Brenda Danek, Marie Pancera, Peter D. Kwong, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

The entry of human immunodeficiency virus (HIV-1) into cells is initiated by binding of the gp120 exterior envelope glycoprotein to the receptor, CD4. How does CD4 binding trigger conformational changes in gp120 that allow the gp41 transmembrane envelope glycoprotein to mediate viral-cell membrane fusion? The transition from the unliganded to the CD4-bound state is regulated by two potentially flexible topological layers (layers 1 and 2) in the gp120 inner domain. Both layers apparently contribute to the noncovalent association of unliganded gp120 with gp41. After CD4 makes initial contact with the gp120 outer domain, layer 1-layer 2 interactions strengthen gp120-CD4 binding …

Neuroaids In Africa, Kevin Robertson, Jeff Liner, James Hakim, Jean-Louis Sankalé, Igor Grant, Scott Letendre, David Clifford, Amadou Gallo Diop, Assan Jaye, Georgette Kanmogne, Alfred Njamnshi, T. Dianne Langford, Tufa Gemechu Weyessa, Charles Wood, Mwanza Banda, Mina Hosseinipour, Ned Sacktor, Noeline Nakasuja, Paul Bangirana, Robert Paul, John Joska, Joseph Wong, Michael Boivin, Penny Holding, Betsy Kammerer, Annelies Van Rie, Prudence Ive, Avindra Nath, Kathy Lawler, Clement Adebamowo, Walter Royal Iii, Jeymohan Joseph

Nebraska Center for Virology: Faculty Publications

In July 2009, the Center for Mental Health Research on AIDS at the National Institute of Mental Health organized and supported the meeting “NeuroAIDS in Africa.” This meeting was held in Cape Town, South Africa, and was affiliated with the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention. Presentations began with an overview of the epidemiology of HIV in sub-Saharan Africa, the molecular epidemiology of HIV, HIV-associated neurocognitive disorders (HANDs), and HAND treatment. These introductory talks were followed by presentations on HAND research and clinical care in Botswana, Cameroon, Ethiopia, The Gambia, Kenya, Malawi, Nigeria, Senegal, South Africa, Uganda, …

Functional Properties Of The Hiv-1 Subtype C Envelope Glycoprotein Associated With Mother-To-Child Transmission, Hong Zhang, Marzena Rola, John T. West, Damien C. Tully, Piotr Kubis, Jun He, Chipepo Kankasa, Charles Wood

Nebraska Center for Virology: Faculty Publications

Understanding the properties of viruses capable of establishing infection during perinatal transmission of HIV-1 is critical for designing effective means of limiting transmission. We previously demonstrated that the newly transmitted viruses (in infant) were more fit in growth, as imparted by their envelope glycoproteins, than those in their corresponding mothers. Here, we further characterized the viral envelope glycoproteins from six mother-infant transmission pairs and determined whether any specific envelope functions correlate with HIV-1 subtype C perinatal transmission. We found that most newly transmitted viruses were less susceptible to neutralization by their maternal plasma compared to contemporaneous maternal viruses. However, the …

Chronology And Evolution Of The Hiv-1 Subtype C Epidemic In Ethiopia, Damien C. Tully, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To reconstruct the onset date and evolutionary history of the HIV-1 subtype C epidemic in Ethiopia - one of the earliest recorded subtype C epidemics in the world.

Design—HIV-1 C env sequences with a known sampling year isolated from HIV-1 positive patients from Ethiopia between 1984 and 2003.

Methods—Evolutionary parameters including origin and demographic growth patterns were estimated using a Bayesian coalescent-based approach under either strict or relaxed molecular clock models.

Results—Bayesian evolutionary analysis indicated a most recent common ancestor date of 1965 with three distinct epidemic growth phases. Regression analysis of root-to-tip distances revealed a highly similar estimate for …

Enhancement Of Autophagy During Lytic Replication By The Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator, Hui-Ju Wen, Zhilong Yang, You Zhou, Charles Wood

Nebraska Center for Virology: Faculty Publications

Autophagy is one of two major degradation systems in eukaryotic cells. The degradation mechanism of autophagy is required to maintain the balance between the biosynthetic and catabolic processes and also contributes to defense against invading pathogens. Recent studies suggest that a number of viruses can evade or subvert the host cell autophagic pathway to enhance their own replication. Here, we investigated the effect of autophagy on the KSHV (Kaposi’s sarcoma-associated herpesvirus) life cycle. We found that the inhibition of autophagy reduces KSHV lytic reactivation from latency, and an enhancement of autophagy can be detected during KSHV lytic replication. In addition, …

Evolutionary Aspects Of Urea Utilization By Fungi, Dhammika H. M. L. P Navarathna, Steven D. Harris, David D. Roberts, Kenneth W. Nickerson

Kenneth Nickerson Papers

The higher fungi exhibit a dichotomy with regard to urea utilization. The hemiascomycetes use urea amidolyase (DUR1,2), whereas all other higher fungi use the nickel-containing urease. Urea amidolyase is an energy-dependent biotincontaining enzyme. It likely arose before the Euascomycete/Hemiascomycete divergence c. 350 million years ago by insertion of an unknown gene into one copy of a duplicated methylcrotonyl CoA carboxylase (MccA). The dichotomy between urease and urea amidolyase coincides precisely with that for the Ni/Co transporter (Nic1p), which is present in the higher fungi that use urease and is absent in those that do not. We suggest that …

Phocine Distemper Virus Induced Demyelination In The Spinal Cord Of Infected Harbor Seals (Phoca Vitulina), Thomas Siemens

All Theses And Dissertations

Phocine Distemper Virus (PDV) is a Morbillivirus that has been responsible for the death of approximately 40,000 phocid seals in the last three decades. The most commonly reported pathology is virally induced demyelination of the cerebrum and brainstem which leaves axons bare and limits their conductivity of action potentials. While these conditions have been studied at length, there is little mention of spinal cord involvement. This study aims to determine whether demyelination found in the brainstem continues into the cervical spinal cord. The results indicate that demyelination in the cervical spinal cord does not occur alongside the brainstem. It is …

Interactions Of The Cellular Sumoylation System With Influenza A Virus And Its Non-Structural Protein Ns1a (Ns1a), Sangita Pal

Open Access Theses & Dissertations

The most important current anti-influenza weapons, vaccination and antiviral drugs, can be rapidly rendered fully ineffective thanks to the virus's high mutational rate, which produces viruses exhibiting new antigenic properties and structural proteins insensitive to the drug's mechanism of action. One attractive alternative is to develop drugs that modulate the activity of cellular systems either required for viral growth or able to neutralize viral growth. Here we demonstrate that the cellular SUMOylation system, a post-translational modification involving the conjugation of the Small Ubiquitin-like MOdifier (SUMO) to specific protein targets using a Ubiquitin-like enzymatic cascade, interacts closely with influenza virus during …

Characterization Of Tram, A Required Bacteroides Fragilis Conjugal Apparatus Protein That Interacts With The B. Fragilis Putative Coupling Protein Bcta And The B. Fragilis Relaxase Protein Bmph, Mai Thi Thanh Nguyen

Dissertations

Bacteroides spp. organisms, the most prominent bacteria of the human colon, are reservoirs of antibiotic resistance genes which promiscuously transfer within and from the genus via conjugation. The B. fragilis clinical isolate LV23 harbors a 37kb conjugative transposon, BTF-37. Two important conjugal apparatus proteins encoded by BTF-37 are BctA, a predicted coupling protein (CP) that powers DNA translocation, and ORF7 (TraM). In this study, we demonstrated that TraM exhibits characteristics of a required conjugal apparatus protein including 1) upregulated expression under conjugation conditions; 2) localization to the bacterial inner membrane; 3) interaction with the putative coupling protein BctA and the …

Real-Time Pcr Method For The Quantification Of Burkholderia Cepacia Complex Attached To Lung Epithelial Cells And Inhibitionn Of That Attachment, Ciara Wight, Gillian Herbert, Ruth Pilkington, Máire Callaghan, Siobhan Mcclean

Articles

To develop a rapid method to quantify the attachment of the cystic fibrosis pathogen, Burkholderia multivorans, to lung epithelial cells (16HBE14o(-)) using real-time PCR with a view to monitoring potential inhibition of lung cell attachment. Mammalian and bacterial DNA were purified from bacteria attached to lung epithelial cells. The relative amount of bacteria attached was determined by amplification of the recA gene relative to the human GAPDH gene, in the presence of SYBR Green. The method was thoroughly validated and shown to correlate well with traditional plating techniques. Inhibition of bacterial attachment with simple sugars was then evaluated by real-time …

Genetic Diversity Among Plasmodium Falciparum Field Isolates In Pakistan Measured With Pcr Genotyping Of The Merozoite Surface Protein 1 And 2, Najia Ghanchi, Andreas Martensson, Johan Ursing, Sana Jafri, Sandor Bereczky, Rabia Hussain, Mohammad Asim Beg

Department of Pathology and Laboratory Medicine

Background:The genetic diversity of Plasmodium falciparum has been extensively studied in various parts of the world. However, limited data are available from Pakistan. This study aimed to establish molecular characterization of P. falciparum field isolates in Pakistan measured with two highly polymorphic genetic markers, i.e. the merozoite surface protein 1 (msp-1) and 2 (msp-2).
Methods:Between October 2005 and October 2007, 244 blood samples from Patients with symptomatic blood-slide confirmed P. falciparum mono-infections attending the Aga Khan University Hospital, Karachi, or its collection units located in Sindh and Baluchistan provinces, Pakistan were collected. The genetic diversity of P. falciparum …

Environmental Implications Of Francisella Tularensis Biofilms, Jeffrey J. Margolis '00

Doctoral Dissertations

Francisella tularensis survives in one of the widest environmental ranges of any pathogen. Numerous mammals and arthropod vectors are infected by this highly virulent organism. How this zoonotic pathogen persists outside of its many hosts remains unexplored. We aimed to examine how F. tularensis interacts with environmental surfaces, and hypothesized that biofilm formation may enable survival of this organism in nature. By understanding the role these surface-attached bacterial communities play in F. tularensis ecology, we hope to gain insight into the mechanisms of environmental persistence and transmission of this pathogen.

We identify chitin as a potential non-host niche for F. …

Gene Expression Profile Of Tumor Cell-Fused Or Noni (Morinda Citrifolia)-Treated Dendritic Cells, Melissa O'Connor

All Dissertations

Dendritic cell-mediated cancer immunotherapy employs several ways to engage tumor antigens. We have demonstrated both in pre-clinical animal studies and early clinical trials that dendritomas, highly purified hybrids between dendritic cells and tumor cells, are superior activators of anti-tumor immunity. In the present study, we examined the expression profile of several inflammatory chemokine and chemokine receptors of dendritomas by RNA microarray and real-time RT-PCR. The results indicate that dendritomas made from immature DCs and tumor cells express higher levels of CCL3, CCL5, and CCL22 and lower levels of CCR2 and CCR5, which mimics LPS matured DCs, while dendritomas made from …

Killing Of Treponema Denticola By Mouse Peritoneal Macrophages, P. Gaibani, C. Vocale, S. Ambretti, F. Cavrini, Jacques Izard, L. Miragliotta, M. T. Pellegrino, V. Sambri

Department of Food Science and Technology: Faculty Publications

Treponema denticola has been identified as an important cause of periodontal disease and hypothesized to be involved in extra-oral infections. The objective of this study was to investigate the role of T. denticola cell length and motility during mouse peritoneal macrophages in vitro uptake. Macrophages, incubated under aerobic and anaerobic conditions, produced a similar amount of TNF-α when stimulated with Escherichia coli LPS. The uptake of FlgE- and CfpA-deficient mutants of T. denticola was significantly increased compared with the wild-type strain, due to cell size or lack of motility. Opsonization with specific antibodies considerably improved the treponemes’ uptake. …

Human Uterine Natural Killer Cells But Not Blood Natural Killer Cells Inhibit Human Immunodeficiency Virus Type 1 Infection By Secretion Of Cxcl12, Teddy F. Mselle, Aexandra L. Howell, Mimi Ghosh, Charles R. Wira, Charles L. Sentman

Dartmouth Scholarship

Natural killer (NK) cells derived from the human female reproductive tract (FRT) are phenotypically and functionally distinct from those obtained from peripheral blood. Because the FRT is a primary site of human immunodeficiency virus type 1 (HIV-1) infection in women, we determined whether soluble factors secreted by uterine-derived NK (uNK) cells inhibit HIV-1 infection. Clonal populations of uNK cells were activated with interleukin-12 (IL-12) and IL-15, and conditioned media (CM) from these cultures evaluated for their ability to inhibit infection of cells by HIV-1_IIIB, HIV-1_NL4.3, and HIV-1_HC4 (X4-tropic) or HIV-1_BaL (R5-tropic) viruses. We found …

Antimicrobial Evaluation Of Novel Fatty Acid Derivatives And Other Natural Antimicrobials, Patricia Nobmann

Doctoral

The food industry has shown increased interest for novel natural antimicrobials due to consumer demand for foods with fewer synthetic additives, increased safety, quality and shelf-life. Concurrently, the emergence of drug resistant bacteria substantiates the need for newer antimicrobial agents. Alternative strategies include the use of novel antimicrobials, such as fatty acid derivatives, essential oils and bacteriocins, with proven antimicrobial properties against a diverse range of bacteria. This study investigated novel carbohydrate fatty acid (CF A) derivatives for their antibacterial activity against a range of pathogenic and spoilage bacteria. A series of mono-substituted CF A derivatives using lauric and caprylic …

Protection Against Mucosal Shiv Challenge By Peptide And Helper-Dependent Adenovirus Vaccines, Eric A. Weaver, Pramod N. Nehete, Bharti P. Nehete, Stephanie J. Buchl, Donna Palmer, David C. Montefiori, Philip Ng, K. Jagannadha Sastry, Michael A. Barry

Nebraska Center for Virology: Faculty Publications

Groups of rhesus macaques that had previously been immunized with HIV-1 envelope (env) peptides and first generation adenovirus serotype 5 (FG-Ad5) vaccines expressing the same peptides were immunized intramuscularly three times with helperdependent adenovirus (HD-Ad) vaccines expressing only the HIV-1 envelope from JRFL. No gag, pol, or other SHIV genes were used for vaccination. One group of the FG-Ad5- immune animals was immunized three times with HD-Ad5 expressing env. One group was immunized by serotype-switching with HD-Ad6, HD-Ad1, and HD-Ad2 expressing env. Previous work demonstrated that serum antibody levels against env were significantly higher in the serotype-switched group than in …

Transitions To And From The Cd4-Bound Conformation Are Modulated By A Single-Residue Change In The Human Immunodeficiency Virus Type 1 Gp120 Inner Domain, Aemro Kassa, Navid Madani, Arne Schön, Hillel Haim, Andrés Finzi, Shi-Hua Xiang, Liping Wang, Amy Princiotto, Marie Pancera, Joel Courter, Amos B. Smith Iii, Ernesto Freire, Peter D. Kwong, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Binding to the primary receptor CD4 induces conformational changes in the human immunodeficiency virus type 1 (HIV-1) gp120 envelope glycoprotein that allow binding to the coreceptor (CCR5 or CXCR4) and ultimately trigger viral membrane-cell membrane fusion mediated by the gp41 transmembrane envelope glycoprotein. Here we report the derivation of an HIV-1 gp120 variant, H66N, that confers envelope glycoprotein resistance to temperature extremes. The H66N change decreases the spontaneous sampling of the CD4-bound conformation by the HIV-1 envelope glycoproteins, thus diminishing CD4-independent infection. The H66N change also stabilizes the HIV-1 envelope glycoprotein complex once the CD4-bound state is achieved, decreasing the …

Overexpression Of A Mutant Form Of Ehraba, A Unique Rab Gtpase Of Entamoeba Histolytica, Alters Endoplasmic Reticulum Morphology And Localization Of The Gal/Galnac Adherence Lectin, B. H. Welter, Lesly A. Temesvari

Publications

Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. Vesicle trafficking events, such as phagocytosis and delivery of plasma membrane proteins, have been implicated in pathogenicity. Rab GTPases are proteins whose primary function is to regulate vesicle trafficking; therefore, understanding the function of Rabs in this organism may provide insight into virulence. E. histolytica possesses a number of unique Rabs that exhibit limited homology to host Rabs. In this study we examined the function of one such Rab, EhRabA, by characterizing a mutant overexpressing a constitutively GTP-bound version of the protein. Overexpression of mutant EhRabA resulted …

Section Abstracts: Biology And Microbiology & Molecular Biology

Virginia Journal of Science

Abstracts of the Biology Section and Microbiology & Molecular Biology for the 87th Annual Meeting of the Virginia Academy of Science, May 27th-29th, 2009, Virginia Commonwealth University, Richmond, VA.