Medical Microbiology Commons^™

Association Between Symptomatic Vulvovaginal Candidiasis And Hiv Rna Levels In Plasma And Genital Secretions Among Women On Haart, Teke Apalata, William H. Carr, Benjamin Longo-Mbenza, Willem A. Sturm, P. Moodley

Publications and Research

Background. Genital tract (GT) inflammation plays a major role in HIV transmission. We aimed to determine the association between symptomatic vulvovaginal candidiasis (VVC) and HIV RNA levels in plasma and GTs of HIV-infected women on highly active antiretroviral therapy (HAART).

Method. Women with VVC on HAART were recruited from a primary healthcare clinic in KwaZulu-Natal Province, South Africa, between June 2011 and December 2011. VVC was diagnosed clinically, supported by Gram staining and culture of genital secretions. HIV RNA load was determined by reverse transcription polymerase chain reaction. CD4+ counts were obtained from patients’ medical records.

Results. Plasma HIV RNA …

Urinary Estrogen Metabolites And Self-Reported Infertility In Women Infected With Schistosoma Haematobium, Julio Santos, Maria Joao Gouveia, Nuno Vale, Maria De Lurdes Delgado, Ana Goncalves, Gabriel Rinaldi, Paul J. Brindley, +10 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Schistosomiasis is a neglected tropical disease, endemic in 76 countries, that afflicts more than 240 million people. The impact of schistosomiasis on infertility may be underestimated according to recent literature. Extracts of Schistosoma haematobium include estrogen-like metabolites termed catechol-estrogens that down regulate estrogen receptors alpha and beta in estrogen responsive cells. In addition, schistosome derived catechol-estrogens induce genotoxicity that result in estrogen-DNA adducts. These catechol estrogens and the catechol-estrogen-DNA adducts can be isolated from sera of people infected with S. haematobium. The aim of this study was to study infertility in females infected with S. haematobium and its …

Structural Features Of The Pseudomonas Fluorescens Biofilm Adhesin Lapa Required For Lapg-Dependent Cleavage, Biofilm Formation, And Cell Surface Localization, Chelsea D. Boyd, T. Jarrod Smith, Sofiane El-Kirat-Chatel, Peter D. Newell, Yves F. Dufrêne, George A. O'Toole

Dartmouth Scholarship

The localization of the LapA protein to the cell surface is a key step required by Pseudomonas fluorescens Pf0-1 to irreversibly attach to a surface and form a biofilm. LapA is a member of a diverse family of predicted bacterial adhesins, and although lacking a high degree of sequence similarity, family members do share common predicted domains. Here, using mutational analysis, we determine the significance of each domain feature of LapA in relation to its export and localization to the cell surface and function in biofilm formation. Our previous work showed that the N terminus of LapA is required for …

Human Antimicrobial Peptides And Proteins, Guangshun Wang

Journal Articles: Pathology and Microbiology

As the key components of innate immunity, human host defense antimicrobial peptides and proteins (AMPs) play a critical role in warding off invading microbial pathogens. In addition, AMPs can possess other biological functions such as apoptosis, wound healing, and immune modulation. This article provides an overview on the identification, activity, 3D structure, and mechanism of action of human AMPs selected from the antimicrobial peptide database. Over 100 such peptides have been identified from a variety of tissues and epithelial surfaces, including skin, eyes, ears, mouths, gut, immune, nervous and urinary systems. These peptides vary from 10 to 150 amino acids …

The Use Of Nanotrap Particles Technology In Capturing Hiv-1 Virions And Viral Proteins From Infected Cells, Elizabeth Jaworski, Mohammed Saifuddin, Gavin C. Sampey, Nazly Shafagati, Rachel Van Duyne, Sergey N. Iordanskiy, Kylene Kehn-Hall, Lance Liotta, Emanuel F. Petricoin Iii, Mary Young, Benjamin Lepene

Microbiology, Immunology, and Tropical Medicine Faculty Publications

HIV-1 infection results in a chronic but incurable illness since long-term HAART can keep the virus to an undetectable level. However, discontinuation of therapy rapidly increases viral burden. Moreover, patients under HAART frequently develop various metabolic disorders and HIV-associated neuronal disease. Today, the main challenge of HIV-1 research is the elimination of the residual virus in infected individuals. The current HIV-1 diagnostics are largely comprised of serological and nucleic acid based technologies. Our goal is to integrate the nanotrap technology into a standard research tool that will allow sensitive detection of HIV-1 infection. This study demonstrates that majority of HIV-1 …

Cd27high/Klrg1low Cd8+ T Cells That Persist Throughout Mcmv Infection Are Highly Expansive And Have The Ability To Reestablish Mcmv Immunity, Michael Quinn, Holly Turula, Christopher M. Snyder

Department of Microbiology and Immunology Faculty Papers

Abstract

Cytomegalovirus (CMV) is a herpesvirus that establishes life-long latency in 60-80% of Americans. Constant immune surveillance is necessary to prevent viral reactivation from latency and results in the accumulation of functional CMV-specific CD8+ T cells (CD8s) over time, a process termed memory inflation. As such, CMV reactivations remain a clinical concern for immunosuppressed patients and reconstituting CMV immunity is critical for the long-term prevention of CMV disease. Understanding the maintenance of memory inflation may reveal novel approaches to restore CMV immunity.

Previous work has shown that the majority of inflationary CD8s express a terminally-differentiated “effector” (T_EFF) phenotype, …

Suppression Of Basophil Histamine-Release And Other Ige-Dependent Responses In Childhood Schistosoma Mansoni Hookworm Co-Infection, Angela Pinot De Moira, Colin M. Fitzsimmons, Frances M. Jones, Shona Wilson, Pierre Cahen, Edridah Tukahebwa, Harriet Mpairwe, Joseph K. Mwatha, Jeffrey M. Bethony, Per S. Skov, Narcis B. Kabatereine, David W. Dunne

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background. The poor correlation between allergen-specific-IgE (asIgE) and clinical signs of allergy in helminth infected populations suggests that helminth infections could protect against allergy by uncoupling asIgE from its effector mechanisms. We investigated this hypothesis in Ugandan schoolchildren coinfected with Schistosoma mansoni and hookworm.

Methods. Skin prick test (SPT) sensitivity to house dust mite allergen (HDM) and current wheeze were assessed pre-anthelmintic treatment. Non-specific (anti-IgE), helminth-specific and HDM-allergen-specific basophil histamine release (HR), plus helminth- and HDM-specific IgE and IgG4 responses were measured pre- and post-treatment.

Results. Non-specific- and helminth-specific-HR, and associations between helminth-specific-IgE and helminth-specific-HR increased post-treatment. Hookworm infection appeared …

Avirulent Strains Of Toxoplasma Gondii Infect Macrophages By Active Invasion From The Phagosome, Yanlin Zhao, Andrew H. Marple, David J. P. Ferguson, David J. Bzik, George S. Yap

Dartmouth Scholarship

Unlike most intracellular pathogens that gain access into host cells through endocytic pathways, Toxoplasma gondii initiates infection at the cell surface by active penetration through a moving junction and subsequent formation of a parasitophorous vacuole. Here, we describe a noncanonical pathway for T. gondii infection of macrophages, in which parasites are initially internalized through phagocytosis, and then actively invade from within a phagosomal compartment to form a parasitophorous vacuole. This phagosome to vacuole invasion (PTVI) pathway may represent an intermediary link between the endocytic and the penetrative routes for host cell entry by intracellular pathogens. The PTVI pathway is preferentially …

The Microbiome In Pediatric Cystic Fibrosis Patients: The Role Of Shared Environment Suggests A Window Of Intervention, Thomas H. Hampton, Deanna M. Green, Garry R. Cutting, Hilary G. Morrison, Mitchell L. Sogin, Alex H. Gifford, Bruce A. Stanton, George A. O’Toole

Dartmouth Scholarship

Cystic fibrosis (CF) is caused by mutations in the CFTR gene that predispose the airway to infection. Chronic infection by pathogens such as Pseudomonas aeruginosa leads to inflammation that gradually degrades lung function, resulting in morbidity and early mortality. In a previous study of CF monozygotic twins, we demonstrate that genetic modifiers significantly affect the establishment of persistent P. aeruginosa colonization in CF. Recognizing that bacteria other than P. aeruginosa contribute to the CF microbiome and associated pathology, we used deep sequencing of sputum from pediatric monozygotic twins and nontwin siblings with CF to characterize pediatric bacterial communities and the …

Limited Brain Metabolism Changes Differentiate Between The Progression And Clearance Of Rabies Virus., Keith Schutsky, Carla Portocarrero, D Craig Hooper, Bernhard Dietzschold, Milosz Faber

Department of Microbiology and Immunology Faculty Papers

Central nervous system (CNS) metabolic profiles were examined from rabies virus (RABV)-infected mice that were either mock-treated or received post-exposure treatment (PET) with a single dose of the live recombinant RABV vaccine TriGAS. CNS tissue harvested from mock-treated mice at middle and late stage infection revealed numerous changes in energy metabolites, neurotransmitters and stress hormones that correlated with replication levels of viral RNA. Although the large majority of these metabolic changes were completely absent in the brains of TriGAS-treated mice most likely due to the strong reduction in virus spread, TriGAS treatment resulted in the up-regulation of the expression of …

Resolving The Titer Of Murine Cytomegalovirus By Plaque Assay Using The M2-10b4 Cell Line And A Low Viscosity Overlay., Katherine A Zurbach, Toktam Moghbeli, Christopher M Snyder

Department of Microbiology and Immunology Faculty Papers

BACKGROUND: Murine cytomegalovirus (MCMV) is increasingly used as an infectious model to investigate host-pathogen interactions in mice. Detailed methods have been published for using primary murine embryonic fibroblasts (MEFs) for preparing stocks and determining viral titers of MCMV. For determining the titer of MCMV by plaque assay, these methods rely on a high viscosity media that restricts viral spreading through the supernatant of the culture, but is also usually too viscous to pipet. Moreover, MEFs must be repeatedly generated and can vary widely from batch-to-batch in purity, proliferation rates, and the development of senescence. In contrast, the M2-10B4 bone marrow …

Evidence For Aberrant Astrocyte Hemichannel Activity In Juvenile Neuronal Ceroid Lipofuscinosis (Jncl)., Maria Burkovetskaya, Nikolay Karpuk, Juan Xiong, Megan Bosch, Michael D. Boska, Hideyuki Takeuchi, Akio Suzumura, Tammy Kielian

Journal Articles: Pathology and Microbiology

Juvenile Neuronal Ceroid Lipofuscinosis (JNCL) is a lysosomal storage disease caused by an autosomal recessive mutation in CLN3 that leads to vision loss, progressive cognitive and motor decline, and premature death. Morphological evidence of astrocyte activation occurs early in the disease process and coincides with regions where neuronal loss eventually ensues. However, the consequences of CLN3 mutation on astrocyte function remain relatively ill-defined. Astrocytes play a critical role in CNS homeostasis, in part, by their ability to regulate the extracellular milieu via the formation of extensive syncytial networks coupled by gap junction (GJ) channels. In contrast, unopposed hemichannels (HCs) have …

Interleukin-7-Dependent B Lymphocytes Are Required For The Anti-Pneumococcal Polysaccharide Response And Protective Immunity To Streptococcus Pneumoniae, Gregory S. Dickinson, Phd, Raja Vuyyuru, Timothy L. Manser, Phd, John F. Kerney, Kishore Alugupalli, Phd

Department of Microbiology and Immunology Faculty Papers

Unlike human adults or adult mice, young children or young mice respond poorly to pneumococcal polysaccharides (PPS). In mice, B1b lymphocytes are the major responders to a variety of bacterial polysaccharides including PPS. Despite having B1b cells, young mice are severely impaired in responding to PPS, suggesting that B cells in the young are distinct from those in adults. Since B lymphopoeisis early in life is largely Interleukin-7 (IL-7)-independent, while in adults it is IL-7-dependent, we hypothesize that B cells developed in the presence of IL-7 are required for generating anti-PPS antibody responses. In support of this, we found that …

Relating The Metatranscriptome And Metagenome Of The Human Gut, Eric A. Franzosa, Xochitl C. Morgan, Nicola Segata, Levi Waldron, Joshua Reyes, Ashlee M. Earl, Georgia Giannoukos, Matthew R. Boylan, Dawn Ciulla, Dirk Gevers, Jacques Izard, Wendy S. Garrett, Andrew T. Chan, Curtis Huttenhower

Department of Food Science and Technology: Faculty Publications

Although the composition of the human microbiome is now well-studied, the microbiota’s > 8 million genes and their regulation remain largely uncharacterized. This knowledge gap is in part because of the difficulty of acquiring large numbers of samples amenable to functional studies of the microbiota. We conducted what is, to our knowledge, one of the first human microbiome studies in a well-phenotyped prospective cohort incorporating taxonomic, metagenomic, and metatranscriptomic profiling at multiple body sites using self-collected samples. Stool and saliva were provided by eight healthy subjects, with the former preserved by three different methods (freezing, ethanol, and RNAlater) to validate self-collection. …

Shape Validated Secondary Structures Of Mason-Pfizer Monkey Virus (Mpmv) And Mouse Mammary Tumor Virus (Mmtv) Packaging Signal Rnas Reveal Pal Helix Loops Functioning As Dimerization Initiation Sites (Dis) Controlling Their Genomic Rna (Grna) Packaging, Suriya Jahan Aktar

Dissertations

The “diploid” genome of retroviruses consists of two strands of RNA that are non-covalently linked as a “dimer” at their 5’ ends. The ubiquitous presence of a dimeric genome among retroviruses suggests that dimerization plays a crucial role in gRNA packaging during viral life-cycle. For almost all retroviruses, determinants of gRNA dimerization and packaging, which are for the most part physically and genetically indistinguishable, reside at the 5’ end of the gRNAs and have been shown to assume higher order structures. Employing a combination of genetic and structural prediction approaches, we have earlier shown that Mason-Pfizer monkey virus (MPMV) and …

An Immunomics Approach To Schistosome Antigen Discovery: Antibody Signatures Of Naturally Resistant And Chronically Infected Individuals From Endemic Areas, Soraya Gaze, Patrick Driguez, Mark S. Pearson, Tiago Mendes, Denise L. Doolan, Jeffrey M. Bethony, +14 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Schistosomiasis is a neglected tropical disease that is responsible for almost 300,000 deaths annually. Mass drug administration (MDA) is used worldwide for the control of schistosomiasis, but chemotherapy fails to prevent reinfection with schistosomes, so MDA alone is not sufficient to eliminate the disease, and a prophylactic vaccine is required. Herein, we take advantage of recent advances in systems biology and longitudinal studies in schistosomiasis endemic areas in Brazil to pilot an immunomics approach to the discovery of schistosomiasis vaccine antigens. We selected mostly surface-derived proteins, produced them using an in vitro rapid translation system and then printed them to …

A Novel Multivalent, Single-Domain Antibody Targeting Tcda And Tcdb Prevents Fulminant Clostridium Difficile Infection In Mice, Zhiyong Yang, Diane Schmidt, Weilong Liu, Shan Li, Lianfa Shi, Jinliang Sheng, Kevin Chen, Hua Yu, Jacqueline M. Tremblay, Xinhua Chen, Kurt H. Piepenbrink, Eric J. Sundberg, Ciaran P. Kelly, Guang Bai, Charles B. Shoemaker, Hanping Feng

Food for Health: Publications

The incidence of Clostridium difficile infection (CDI) and associated mortality have increased rapidly worldwide in recent years. Therefore, it is critical to develop new therapies for CDI. In this study, we generated a novel, potently neutralizing, tetravalent, and bispecific antibody composed of 2 heavy-chain-only V_H (V_HH) binding domains against both TcdA and TcdB (designated “ABA”) that reverses fulminant CDI in mice infected with an epidemic 027 strain after a single injection of the antibody. We demonstrated that ABA bound to both toxins simultaneously and displayed a significantly enhanced neutralizing activity both in vitro and in vivo. Additionally, …

Microbiota, Oral Microbiome, And Pancreatic Cancer, Dominique S. Michaud, Jacques Izard

Department of Food Science and Technology: Faculty Publications

Only 30% of patients diagnosed with pancreatic cancer survive one year post-diagnosis. Progress in understanding the causes of pancreatic cancer has been made, including solidifying the associations with obesity and diabetes, and a proportion of cases should be preventable through lifestyle modifications. Unfortunately, identifying reliable biomarkers of early pancreatic cancer has been extremely challenging, and no effective screening modality is currently available for this devastating form of cancer. Recent data suggest the microbiota may play a role in the disease process, but many questions remain. Future studies focusing on the human microbiome, both etiologically and as a marker of disease …

Functional Proteomic Analysis Reveals The Involvement Of Kiaa1199 In Breast Cancer Growth, Motility And Invasiveness., Mohammad-Saeid Jami, Jinxuan Hou, Miao Liu, M L. Varney, Hesham Hassan, Jixin Dong, Liying Geng, J. Wang, Fang Yu, Xin Huang, Hong Peng, Kai Fu, Yan Li, Rakesh Singh, Shi-Jian Ding

Journal Articles: Pathology and Microbiology

BACKGROUND: KIAA1199 is a recently identified novel gene that is up-regulated in human cancer with poor survival. Our proteomic study on signaling polarity in chemotactic cells revealed KIAA1199 as a novel protein target that may be involved in cellular chemotaxis and motility. In the present study, we examined the functional significance of KIAA1199 expression in breast cancer growth, motility and invasiveness.

METHODS: We validated the previous microarray observation by tissue microarray immunohistochemistry using a TMA slide containing 12 breast tumor tissue cores and 12 corresponding normal tissues. We performed the shRNA-mediated knockdown of KIAA1199 in MDA-MB-231 and HS578T cells to …

Autoantibodies To Agrin In Myasthenia Gravis Patients, Bin Zhang, Chengyong Shen, Beverly Bealmear, Samia Ragheb, Wen-Cheng Xiong, Richard A. Lewis, Robert P. Lisak, Lin Mei

Immunology and Microbiology Faculty Research Publications

To determine if patients with myasthenia gravis (MG) have antibodies to agrin, a proteoglycan released by motor neurons and is critical for neuromuscular junction (NMJ) formation, we collected serum samples from 93 patients with MG with known status of antibodies to acetylcholine receptor (AChR), muscle specific kinase (MuSK) and lipoprotein-related 4 (LRP4) and samples from control subjects (healthy individuals and individuals with other diseases). Sera were assayed for antibodies to agrin. We found antibodies to agrin in 7 serum samples of MG patients. None of the 25 healthy controls and none of the 55 control neurological patients had agrin antibodies. …