Digital Commons Network^™

The Role Of Cd4 T Cells In The Pathogenesis Of Murine Aids, Wen Li, William R. Green

Dartmouth Scholarship

LP-BM5, a retroviral isolate, induces a disease featuring retrovirus-induced immunodeficiency, designated murine AIDS (MAIDS). Many of the features of the LP-BM5-induced syndrome are shared with human immunodeficiency virus-induced disease. For example, CD4 T cells are critical to the development of MAIDS. In vivo depletion of CD4 T cells before LP-BM5 infection rendered genetically susceptible B6 mice MAIDS resistant. Similarly, MAIDS did not develop in B6.nude mice. However, if reconstituted with CD4 T cells, B6.nude mice develop full-blown MAIDS. Our laboratory has shown that the interaction of B and CD4 T cells that is central to MAIDS pathogenesis requires ligation of …

Conjugative Transfer Pathways Of High-Level Mupirocin Resistance And Conjugative Transfer Genes In Staphylococcus., Danielle Barnard

Electronic Theses and Dissertations

To combat widespread infections caused by Staphylococcus aureus, mupirocin was introduced at the Veterans Affairs Medical Center, Mountain Home, Tennessee. Soon after introduction, high-level mupirocin-resistance emerged. The rapid emergence was hypothesized to be due to conjugative transfer of the mupA resistance gene from S. epidermidis to S. aureus. Results have shown that transfer of high-level mupirocin-resistance from S. aureus donors commonly occurs. However, transfer from naturally-occurring S. epidermidis donors was not attainable. Staphylococcus epidermidis transconjugants, however, were capable of serving as donors. Further examination of non-transmissibility included PCR analysis of conjugative transfer genes (tra genes) in capable …

The Cost Of Mupirocin Resistance In Staphylococcus., Susan D. Reynolds

Electronic Theses and Dissertations

Control of antibiotic resistance in bacteria is based on the concept that resistance incurs a fitness cost in non-selective conditions. Fitness costs were assessed for low- and high-level mupirocin resistance in locally-derived Staphylococcus aureus and S. epidermidis. Costs of resistance were assessed in pure cultures by comparing growth curve characteristics and in mixed culture as the proportion of resistant cells surviving. Costs were not present in comparisons of growth rates among groups of naturally-occurring isolates from the different resistance categories. However, in S. aureus, growth rates within resistance categories differed by approximately 30 – 90%. Among near-isogenic pairs …

In Vitro Expression And Purification Of Class I Mhc Molecules, Loi Cheng

Honors Scholar Theses

The major histocompatibility complex (MHC) is a gene family responsible for many critical functions of the immune system in most vertebrates. The MHC consists of three classes differentiated by their structure and function, and MHC class I encodes antigen binding proteins as well as chaperone and accessory proteins such as tapasin. The purpose of this project is to reconstitute several human MHC class I molecules in their peptide-filled and peptide-deficient forms, and to purify these proteins for biochemical study. The expressed proteins include wild type and mutant variants of the fusion protein human leukocyte antigen HLA-B*0801-fos, and human beta-2-microglobulin (β2m). …

The Latent Membrane Protein 1 Of Epstein-Barr Virus (Ebv) Primes Ebv Latency Cells For Type I Interferon Production, Dongsheng Xu, Kristen Brumm, Luwen Zhang

Nebraska Center for Virology: Faculty Publications

Epstein-Barr virus (EBV) latency has been associated with a variety of human cancers. Latent membrane protein 1 (LMP-1) is one of the key viral proteins required for transformation of primary B cells in vitro and establishment of EBV latency. We have previously shown that LMP-1 induces the expression of several interferon (IFN)-stimulated genes and has antiviral effect (Zhang, J., Das, S. C., Kotalik, C., Pattnaik, A. K., and Zhang, L. (2004) J. Biol. Chem. 279, 46335–46342). In this report, a novel mechanism related to the antiviral effect of LMP-1 is identified. We show that EBV type III latency cells, in …

Keeping Their Options Open: Acute Versus Persistent Infections, S. Furukawa, S. L. Kuchma, G. A. O'Toole

Dartmouth Scholarship

No abstract provided.

Expression Of Heterologous Proteins In Transgenic Tobacco Chloroplasts To Produce A Biopharmaceutical And Biopolymer, Andrew Leon Devine

Electronic Theses and Dissertations

The chloroplast has been demonstrated to be an ideal compartment to accumulate certain proteins or their biosynthetic products that would be harmful if they were accumulated in the cytoplasm. Hyper-expression of foreign proteins in chloroplast transgenics has accumulated up to 46% total soluble protein, this is possible due to the ~100 chloroplast genomes per chloroplast and ~100 chloroplasts per cell which can therefore, contain up to 10,000 copies of the transgene. Maternal gene inheritance of plastids in most crop plants results in natural gene containment. Chloroplast transformation also eliminates positional effects that are frequently observed with nuclear transformation and no …

Prevalence And Serovars Of Salmonella In The Feces Of Free-Ranging White-Tailed Deer (Odocoileus Virginianus) In Nebraska, David G. Renter, David P. Gnad, Jan M. Sargeant, Scott E. Hygnstrom

School of Natural Resources: Faculty Publications

To determine the prevalence and serovars of Salmonella in free-ranging deer, we cultured feces from white-tailed deer (Odocoileus virginianus) harvested by hunters during a regular firearm season in southeastern Nebraska (USA). We recovered Salmonella from 5 (1%; 95% confidence interval: 0.37– 2.20%) of 500 samples and identified four different Salmonella enterica serovars [Litchfield (1), Dessau (1), Infantis (2), and Enteritidis (1)]. Although the prevalence of Salmonella in free-ranging deer appears to be low, the serovars recovered are known to be pathogenic to humans and animals.

Antibiotic Resistant And Coliform Bacteria In The Ohio River; 2002 To 2004, Lisa Marie Smith

Theses, Dissertations and Capstones

During 2002 and 2003 samples, collected every five miles along the Ohio River, were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, erythromycin resistant bacteria, tetracycline resistant bacteria, and fecal coliforms. During 2004 samples were analyzed for total cultivable bacteria, ciprofloxacin resistant bacteria, sulfamethizole resistant bacteria, tetracycline resistant bacteria, Virginiamycin resistant bacteria, total coliforms, and Escherichia coli. The objectives of this study were to systematically collect data on fecal coliforms, E. coli, and antibiotic resistant bacteria in the Ohio River and its major tributaries; to determine if antibiotic resistance populations are correlated to each other or to coliforms; and …

Concomitant Antibiotic And Mercury Resistance Among Gastrointestinal Microflora Of Feral Brook Trout, Salvelinus Fontinalis, Matt Meredith

Undergraduate Research Symposium (UGRS)

No abstract provided.

A Group M Consensus Envelope Glycoprotein Induces Antibodies That Neutralize Subsets Of Subtype B And C Hiv-1 Primary Viruses, Hua-Xin Lin, Laura L. Sutherland, Shi-Mao Xia, Mary E. Brock, Richard M. Scearce, Stacie Vanleeuwen, S. Munir Alam, Mildred Mcadams, Eric A. Weaver, Zenaido T. Camacho, Ben-Jiang Ma, Yingying Li, Julie M. Decker, Gary J. Nabel, David C. Montefiori, Beatrice H. Hahn, Bette T. Korber, Feng Gao, Barton F. Haynes

Nebraska Center for Virology: Faculty Publications

HIV-1 subtype C is the most common HIV-1 group M subtype in Africa and many parts of Asia. However, to date HIV-1 vaccine candidate immunogens have not induced potent and broadly neutralizing antibodies against subtype C primary isolates. We have used a centralized gene strategy to address HIV-1 diversity, and generated a group M consensus envelope gene with shortened consensus variable loops (CON-S) for comparative studies with wildtype (WT) Env immunogens. Our results indicate that the consensus HIV-1 group M CON-S Env elicited cross-subtype neutralizing antibodies of similar or greater breadth and titer than the WT Envs tested, indicating the …

Matrix Metalloproteinase-9 Amplifies The Immune Response To Pseudomonas Aeruginosa Corneal Infection, Sharon A. Mcclellan, Xi Huang, Ronald P. Barrett, Shahrzad Lighvani, Yunfan Zhang, Dawn Richiert, Linda D. Hazlett

Peer Reviewed Articles

PURPOSE. The purpose of this study was to determine the role of matrix metalloproteinases (MMP) in Pseudomonas aeruginosa keratitis.

METHODS. Gene array and selective real-time PCR examined MMP expression in the cornea of susceptible (C57BL/6, B6) versus resistant (BALB/c) mice before and after infection; zymography tested enzyme activity for MMP-2 and -9. Clinical score, Langerhans cell (LC), and Neutrophil (PMN) quantitation were done in recombinant (r) MMP-9, antibody neutralized, and MMP-9^−/− mice. The chemotactic potential of MMP-9 was tested in a Boyden chamber assay; light and transmission microscopy and immunostaining for collagen IV and MMP-9 were used …

Susceptibility Of Primary Eosinophils To Infection With Hiv-1 Strain Htlv-Iiib, Jai Govind Marathe

Browse all Theses and Dissertations

Over the past two decades, much research has been done in the field of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). However, many of the aspects of pathogenesis of HIV infection and its persistence in the body, despite treatment, remain a mystery. Recent evidence suggests that HIV positive patients develop eosinophilia, especially in the later stages of infection and AIDS. Eosinophils are CD4 positive cells that have the potential to be infected by HIV. Studies have shown that an eosinophilic cell line, AML14.3D10, can be productively infected with a T-cell tropic, CXCR4-using (X4) strain of HIV-1. In this …

Phenotypic Characterization Of Escherichia Coli Strains Taken From Human Intestinal And Urinary Tracts, Kruthi Murthy

Browse all Theses and Dissertations

Escherichia coli (E. coli) is a gram negative bacterium commonly found as a commensal in the intestinal tract of humans and other warm blooded animals. The commensal strains of E. coli are non-pathogenic and do not cause an infection in the host. However, some strains of E. coli are pathogenic and can cause several diseases in humans that include neonatal meningitis, intestinal infections and urinary tract infections. Almost 80-85% of the uncomplicated urinary tract infections are caused by uropathogenic E. coli. Our project involved the characterization of 12 strains of E. coli, isolated from humans in health and disease. These …

Myxozoan Genera: Definition And Notes On Taxonomy, Life-Cycle Terminology And Pathogenic Species, Jiří Lom, Iva Dyková

Harold W. Manter Laboratory of Parasitology: Library Materials

A list of myxozoan genera is presented in the current taxonomical scheme. These genera are defined; their type species and most important pathogens along with their hosts are listed. Simultaneously, definitions of actinospore stages representing sexual stages of the myxosporean life cycle are given; altogether, 17 actinospore collective groups with 180 types have been described. Life cycles of the two classes of the phylum Myxozoa, Malacosporea and Myxosporea, are briefly outlined with specification of the appropriate terms. Up to now, 4 malacosporean and 2,180 myxosporean species assigned to a total of 62 genera, have been established. The surviving classification of …

Design Clues From Functional Constraints And Broadly Neutralizing Antibodies, Tongqing Zhou, Ling Xu, Barna Dey, Ann J. Hessell, Shahzad Majeed, Donald Van Ryk, Shi-Hua Xiang, Xinzhen Yang, Mei-Yun Zhang, Michael B. Zwick, James Arthos, Dennis R. Burton, Dimiter S. Dimitrov, Joseph Sodroski, Richard Wyatt, Gary J. Nabel, Peter D. Kwong

Nebraska Center for Virology: Faculty Publications

No abstract provided.

Cross-Subtype T-Cell Immune Responses Induced By A Human Immunodeficiency Virus Type 1 Group M Consensus Env Immunogen, Eric A. Weaver, Zenaido T. Camacho, Fatiha Moukdar, Hua-Xin Liao, Ben-Jiang Ma, Mark Muldoon, James Theiler, Gary J. Nabel, Norman L. Letvin, Bette T. Korber, Beatrice H. Hahn, Barton F. Haynes, Feng Gao, Zhongjing Lu

Nebraska Center for Virology: Faculty Publications

The genetic diversity among globally circulating human immunodeficiency virus type 1 (HIV-1) strains is a serious challenge for HIV-1 vaccine design. We have generated a synthetic group M consensus env gene (CON6) for induction of cross-subtype immune responses and report here a comparative study of T-cell responses to this and natural strain env immunogens in a murine model. Three different strains of mice were immunized with CON6 as well as subtype A, B, or C env immunogens, using a DNA prime-recombinant vaccinia virus boost strategy. T-cell epitopes were mapped by gamma interferon enzyme-linked immunospot analysis using five overlapping Env peptide …

Transposon Disruption Of The Complex I Nadh Oxidoreductase Gene (Snod) In Staphylococcus Aureus Is Associated With Reduced Susceptibility To The Microbicidal Activity Of Thrombin-Induced Platelet Microbicidal Protein 1, Arnold S. Bayer, Peter Mcnamara, Michael R. Yeaman, Natalie Lucindo, Tiffanny Jones, Ambrose L. Cheung

Dartmouth Scholarship

The cationic molecule thrombin-induced platelet microbicidal protein 1 (tPMP-1) exerts potent activity against Staphylococcus aureus. We previously reported that a Tn551 S. aureus transposon mutant, ISP479R, and two bacteriophage back-transductants, TxA and TxB, exhibit reduced in vitro susceptibility to tPMP-1 (tPMP-1(r)) compared to the parental strain, ISP479C (V. Dhawan, M. R. Yeaman, A. L. Cheung, E. Kim, P. M. Sullam, and A. S. Bayer, Infect. Immun. 65:3293-3299, 1997). In the current study, the genetic basis for tPMP-1(r) in these mutants was identified. GenBank homology searches using sequence corresponding to chromosomal DNA flanking Tn551 mutant strains showed that the fourth gene …

Extraneural Prion Neuroinvasion Without Lymphoreticular System Infection, Jason C. Bartz, Crista Dejoia, Tammy Tucker, Anthony E. Kincaid, Richard A. Bessen

Nebraska Center for Virology: Faculty Publications

While prion infection of the lymphoreticular system (LRS) is necessary for neuroinvasion in many prion diseases, in bovine spongiform encephalopathy and atypical cases of sheep scrapie there is evidence to challenge that LRS infection is required for neuroinvasion. Here we investigated the role of prion infection of LRS tissues in neuroinvasion following extraneural inoculation with the HY and DY strains of the transmissible mink encephalopathy (TME) agent. DY TME agent infectivity was not detected in spleen or lymph nodes following intraperitoneal inoculation and clinical disease was not observed following inoculation into the peritoneum or lymph nodes, or after oral ingestion. …

Mannose Binding Lectin Genotypes Influence Recovery From Hepatitis B Virus Infection, Chloe L. Thio, Timothy L. Mosbruger, Jacquie Astemborski, Spencer Greer, Gregory D. Kirk, Stephen J. O'Brien, David L. Thomas

Biology Faculty Articles

Mannose binding lectin (MBL) is a central component of the innate immune response and thus may be important for determining hepatitis B virus (HBV) persistence. Since single-nucleotide polymorphisms (SNPs) in the gene encoding MBL (mbl2) alter the level of functional MBL, we hypothesized that mbl2 genotypes are a determinant of HBV persistence or recovery from viral infection. We tested this hypothesis by using a nested case control design with 189 persons with HBV persistence matched to 338 individuals who had naturally recovered from HBV infection. We determined genotypes of two promoter and three exon 1 SNPs in mbl2 …

Functional Mimicry Of A Human Immunodeficiency Virus Type 1 Coreceptor By A Neutralizing Monoclonal Antibody, Shi-Hua Xiang, Michael Farzan, Zhihai Si, Navid Madani, Liping Wang, Eric Rosenberg, James Robinson, Joseph Sodroski

Nebraska Center for Virology: Faculty Publications

Interaction of the human immunodeficiency virus type 1 (HIV-1) gp120 envelope glycoprotein with the primary receptor, CD4, promotes binding to a chemokine receptor, either CCR5 or CXCR4. The chemokine receptor-binding site on gp120 elicits CD4-induced (CD4i) antibodies in some HIV-1-infected individuals. Like CCR5 itself, the CD4i antibody 412d exhibits a preference for CCR5-using HIV-1 strains and utilizes sulfated tyrosines to achieve binding to gp120. Here, we show that 412d binding requires the gp120 β19 strand and the base of the V3 loop, elements that are important for the binding of the CCR5 N terminus. Two gp120 residues in the V3 …

The Defensin Gene In Dermacentor Variabilis And Ixodes Scapularis, Katherine Corbett Seguin

Biological Sciences Theses & Dissertations

In response to microbial challenge, invertebrates rely on their innate immune response to recognize and destroy harmful pathogens. One of the primary proteins produced by the response and that has been observed in many invertebrates, including insects, mussels, and ticks, is defensin. These proteins are responsible for forming pores in the membranes of invading microbes thereby destroying them. This study examined the gene coding region for defensin in two important tick disease vectors, Dermacentor variabilis and Ixodes scapularis. PCR amplification of the genes from tick chromosomal DNA resulted in the amplification of a 225 base pair amplicon. Sequencing of …

Real Time Rt-Pcr For Direct Detection Of Viable Mycobacterium Avium Subspecies Paratuberculosis In Chron's Disease Patients And Association Of Map Infection With Downregulation In Interferon-Gamma Receptor (Infg1) Gene In Crohn's Disease Patients, Mounir Chehtane

Electronic Theses and Dissertations

Association of Mycobacterium avium subspecies paratuberculosis (MAP) with Crohn's disease (CD) and not with ulcerative colitis (UC), two forms of inflammatory bowel disease (IBD), has been vigorously debated in recent years. This theory has been strengthened by recent culture of MAP from breast milk, intestinal tissue and Blood from patients with active Crohn's disease. Culture of MAP from clinical samples remained challenging due to the fastidious nature of MAP including its lack of cell wall in infected patients. The advent of real time PCR has proven to be significant in infectious disease diagnostics. In this study, real time reverse transcriptase …

Etiology Of Oral Disease In View Of Microbial Complexity, Anne C. R. Tanner, Jacques Izard

Department of Food Science and Technology: Faculty Publications

The number of different microorganisms recognized in the oral cavity using molecular methods has more than doubled compared with the number isolated using cultural techniques. This finding necessitates a reevaluation of which species may be pathogens in dental infections. Molecular methods used to determine microbial diversity include broad range target Polymerase Chain Reaction with ‘universal primers,’ and cloning amplicons or denaturing gradient gel electrophoresis to separate DNA fragments before sequencing. These molecular methods have clarified and expanded the taxonomy of oral microbial species. Discrepancies between comprehensive molecular and cultural methods suggest that neither method alone can adequately evaluate associations of …

Replication And Encapsidation Of Papillomaviruses In Saccharomyces Cerevisiae, Peter C. Angeletti

Nebraska Center for Virology: Faculty Publications

Improvements in methodologies to recapitulate and study particular biological functions of the

papillomavirus life cycle have led to great advances in our knowledge of these viruses. Described in

this chapter are techniques that allow low-copy and high-copy replication of full-length human

papillomavirus (HPV) genomes, as well as assembly of virus-like particles, in Saccharomyces

cerevisiae (yeast). This system has several distinct advantages that make it an attractive complement

to the well-established raft-culturing system. First, yeast are inexpensive, rapid, and simple to culture

in the lab. Second, they provide an ever-widening array of genetic tools to analyze HPV functions

—most recently notable, …

Antigenicity And Immunogenicity Of A Synthetic Human Immunodeficiency Virus Type 1 Group M Consensus Envelope Glycoprotein, Feng Gao, Eric A. Weaver, Zhongjing Lu, Yingying Li, Hua-Xin Liao, Benjiang Ma, S. Munir Alam, Richard M. Scearce, Laura L. Sutherland, Jae-Sung Yu, Julie M. Decker, George M. Shaw, David C. Montefiori, Bette T. Korber, Beatrice H. Hahn, Barton F. Haynes

Nebraska Center for Virology: Faculty Publications

Genetic variation of human immunodeficiency virus (HIV-1) represents a major obstacle for AIDS vaccine development. To decrease the genetic distances between candidate immunogens and field virus strains, we have designed and synthesized an artificial group M consensus env gene (CON6 gene) to be equidistant from contemporary HIV-1 subtypes and recombinants. This novel envelope gene expresses a glycoprotein that binds soluble CD4, utilizes CCR5 but not CXCR4 as a coreceptor, and mediates HIV-1 entry. Key linear, conformational, and glycan-dependent monoclonal antibody epitopes are preserved in CON6, and the glycoprotein is recognized equally well by sera from individuals infected with different HIV-1 …

Antigenicity And Immunogenicity Of A Synthetic Human Immunodeficiency Virus Type 1 Group M Consensus Envelope Glycoprotein, Feng Gao, Eric A. Weaver, Zhongjing Lu, Yingying Li, Hua-Xin Liao, Benjiang Ma, S. Munir Alam, Richard M. Scearce, Laura L. Sutherland, Jae-Sung Yu, Julie M. Decker, George M. Shaw, David C. Montefiori, Bette T. Korber, Beatrice H. Hahn, Barton F. Haynes

Nebraska Center for Virology: Faculty Publications

Genetic variation of human immunodeficiency virus (HIV-1) represents a major obstacle for AIDS vaccine development. To decrease the genetic distances between candidate immunogens and field virus strains, we have designed and synthesized an artificial group M consensus env gene (CON6 gene) to be equidistant from contemporary HIV-1 subtypes and recombinants. This novel envelope gene expresses a glycoprotein that binds soluble CD4, utilizes CCR5 but not CXCR4 as a coreceptor, and mediates HIV-1 entry. Key linear, conformational, and glycan-dependent monoclonal antibody epitopes are preserved in CON6, and the glycoprotein is recognized equally well by sera from individuals infected with different HIV-1 …

Ridding Ships' Ballast Water Of Microorganisms, Fred C. Dobbs, Andrew Rogerson

OES Faculty Publications

( First paragraph) A complex assemblage of microorganisms exists in nearly every aquatic system on earth. In lakes and oceans, every milliliter of water contains about 10² protists (single-celled eukaryotes), 10⁶ bacteria, and 10⁷–10⁹ viruses. Therefore, billions of microorganisms inevitably enter ships’ ballast tanks during normal operations. It has been argued that microorganisms must certainly be frequent invaders of coastal ecosystems, given the high densities of bacteria and viruses in ballast water—10⁸ and 10⁹ organisms per liter, respectively (1)—their potentially high reproductive rates, broad tolerances to physical conditions, and ability to form resting …

Association Of Dc-Sign Promoter Polymorphism With Increased Risk For Parenteral, But Not Mucosal, Acquisition Of Human Immunodeficiency Virus Type 1 Infection, Maureen P. Martin, Michael M. Lederman, Holli B. Hutcheson, James J. Goedert, George W. Nelson, Yvette Van Kooyk, Roger Detels, Susan Buchbinder, Keith Hoots, David Vlahov, Stephen J. O'Brien, Mary Carrington

Biology Faculty Articles

There is considerable debate about the fundamental mechanisms that underlie and restrict acquisition of human immunodeficiency virus type 1 (HIV-1) infection. In light of recent studies demonstrating the ability of C type lectins to facilitate infection with HIV-1, we explored the potential relationship between polymorphisms in the DC-SIGN promoter and risk for acquisition of HIV-1 according to route of infection. Using samples obtained from 1,611 European-American participants at risk for parenteral (n = 713) or mucosal (n = 898) infection, we identified single-nucleotide polymorphisms in the DC-SIGN promoter using single-strand conformation polymorphism. Individuals at risk for parenterally acquired …

The Potential Role Of Ledgf/P75 In Prostate Cancer, Tracy Ruth Daniels

Loma Linda University Electronic Theses, Dissertations & Projects

The serum autoantibody repertoire from cancer patients is currently being exploited for the identification of tumor associated antigens (TAA) and the design of TAA arrays. Such arrays would facilitate autoantibody profiling and potentially aid in the serological diagnosis and prognosis of tumors. The goal of this study was to identify and characterize prostate-specific TAA. We observed that while the general frequency and titers of autoantibodies in PCa patients were relatively similar to those in matched controls, significant differences could be detected between the two groups in the autoantibody response to the lens epithelial-derived growth factor p75 (LEDGF/p75). LEDGF/p75 is a …