Tropical Medicine Commons^™

Advances In Neglected Tropical Disease Vaccines: Developing Relative Potency And Functional Assays For The Na-Gst-1/Alhydrogel Hookworm Vaccine., Jill B. Brelsford, Jordan L Plieskatt, Anna Yakovleva, Amar Jariwala, Brian P Keegan, Jin Peng, Pengjun Xia, Guangzhao Li, Doreen Campbell, Maria Victoria Periago, Rodrigo Correa-Oliveira, Maria Elena Bottazzi, Peter J. Hotez, David Diemert, Jeffrey M. Bethony

Microbiology, Immunology, and Tropical Medicine Faculty Publications

A new generation of vaccines for the neglected tropical diseases (NTDs) have now advanced into clinical development, with the Na-GST-1/Alhydrogel Hookworm Vaccine already being tested in Phase 1 studies in healthy adults. The current manuscript focuses on the often overlooked critical aspects of NTD vaccine product development, more specifically, vaccine stability testing programs. A key measure of vaccine stability testing is "relative potency" or the immunogenicity of the vaccine during storage. As with most NTD vaccines, the Na-GST-1/Alhydrogel Hookworm Vaccine was not developed by attenuation or inactivation of the pathogen (Necator americanus), so conventional methods for measuring relative potency are …

Parasite Infection, Carcinogenesis And Human Malignancy., Hoang Van Tong, Paul J. Brindley, Christian G Meyer, Thirumalaisamy P Velavan

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Cancer may be induced by many environmental and physiological conditions. Infections with viruses, bacteria and parasites have been recognized for years to be associated with human carcinogenicity. Here we review current concepts of carcinogenicity and its associations with parasitic infections. The helminth diseases schistosomiasis, opisthorchiasis, and clonorchiasis are highly carcinogenic while the protozoan Trypanosoma cruzi, the causing agent of Chagas disease, has a dual role in the development of cancer, including both carcinogenic and anticancer properties. Although malaria per se does not appear to be causative in carcinogenesis, it is strongly associated with the occurrence of endemic Burkitt lymphoma in …

Yeast Help Identify Cytopathic Factors Of Zika Virus, Michael I. Bukrinsky

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Accumulating evidence implicates Zika virus (ZIKV) in pathogenesis of microcephaly in newborns and Guillain-Barré syndrome in adults. However, it remains unclear which viral proteins are responsible for these effects and what are the underlying mechanisms of their pathogenic activity. A recent paper by Drs. Zhao and Gallo, and their colleagues at University of Maryland in Baltimore used fission yeast for genome-wide analysis of ZIKV proteins. They demonstrated cytopathogenic activity for seven ZIKV proteins, anaC, C, prM, M, E, NS2B and NS4A. This activity was shown to be dependent on oxidative stress, and for NS4A they demonstrated involvement of the TOR …

A Comparison Of The Quality Of Informed Consent For Clinical Trials Of An Experimental Hookworm Vaccine Conducted In Developed And Developing Countries., David J. Diemert, Lucas Lobato, Ashley Styczynski, Maria Zumer, Amanda Soares, Maria Flávia Gazzinelli

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Informed consent is one of the principal ethical requirements of conducting clinical research, regardless of the study setting. Breaches in the quality of the informed consent process are frequently described in reference to clinical trials conducted in developing countries, due to low levels of formal education, a lack of familiarity with biomedical research, and limited access to health services in these countries. However, few studies have directly compared the quality of the informed consent process in developed and developing countries using the same tool and in similar clinical trials. This study was conducted to compare the quality of the informed …

Identification Of Candidate Infection Genes From The Model Entomopathogenic Nematode Heterorhabditis Bacteriophora., Jonathan Vadnal, Ramesh Ratnappan, Melissa Keaney, Eric Kenney, Ioannis Eleftherianos, Damien O'Halloran, John M. Hawdon

Microbiology, Immunology, and Tropical Medicine Faculty Publications

BACKGROUND: Despite important progress in the field of innate immunity, our understanding of host immune responses to parasitic nematode infections lags behind that of responses to microbes. A limiting factor has been the obligate requirement for a vertebrate host which has hindered investigation of the parasitic nematode infective process. The nematode parasite Heterorhabditis bacteriophora offers great potential as a model to genetically dissect the process of infection. With its mutualistic Photorhabdus luminescens bacteria, H. bacteriophora invades multiple species of insects, which it kills and exploits as a food source for the development of several nematode generations. The ability to culture …

Genomes Of Fasciola Hepatica From The Americas Reveal Colonization With Neorickettsia Endobacteria Related To The Agents Of Potomac Horse And Human Sennetsu Fevers., Samantha N Mcnulty, Jose F Tort, Gabriel Rinaldi, Bruce A Rosa, Victoria H. Mann, Patricia S. Latham, Paul J. Brindley, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Food borne trematodes (FBTs) are an assemblage of platyhelminth parasites transmitted through the food chain, four of which are recognized as neglected tropical diseases (NTDs). Fascioliasis stands out among the other NTDs due to its broad and significant impact on both human and animal health, as Fasciola sp., are also considered major pathogens of domesticated ruminants. Here we present a reference genome sequence of the common liver fluke, Fasciola hepatica isolated from sheep, complementing previously reported isolate from cattle. A total of 14,642 genes were predicted from the 1.14 GB genome of the liver fluke. Comparative genomics indicated that F. …

Fit For Genomic And Proteomic Purposes: Sampling The Fitness Of Nucleic Acid And Protein Derivatives From Formalin Fixed Paraffin Embedded Tissue., Anna Yakovleva, Jordan L Plieskatt, Sarah Jensen, Razan Humeida, Jonathan Lang, Guangzhao Li, Paige Bracci, Sylvia Silver, Jeffrey Michael Bethony

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The demand for nucleic acid and protein derivatives from formalin-fixed paraffin-embedded (FFPE) tissue has greatly increased due to advances in extraction and purification methods, making these derivatives available for numerous genomic and proteomic platforms. Previously, DNA, RNA, microRNA (miRNA), or protein derived from FFPE tissue blocks were considered “unfit” for such platforms, as the process of tissue immobilization by FFPE resulted in cross-linked, fragmented, and chemically modified macromolecules. We conducted a systematic examination of nucleic acids and proteins co-extracted from 118 FFPE blocks sampled from the AIDS and Cancer Specimen Resource (ACSR) at The George Washington University after stratification by …

Schistosoma Mansoni Reinfection: Analysis Of Risk Factors By Classification And Regression Tree (Cart) Modeling., Andréa Gazzinelli, Roberta Oliveira-Prado, Leonardo Ferreira Matoso, Bráulio M Veloso, Gisele Andrade, Helmut Kloos, Jeffrey M Bethony, Renato M Assunção, Rodrigo Correa-Oliveira

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Praziquantel (PZQ) is an effective chemotherapy for schistosomiasis mansoni and a mainstay for its control and potential elimination. However, it does not prevent against reinfection, which can occur rapidly in areas with active transmission. A guide to ranking the risk factors for Schistosoma mansoni reinfection would greatly contribute to prioritizing resources and focusing prevention and control measures to prevent rapid reinfection. The objective of the current study was to explore the relationship among the socioeconomic, demographic, and epidemiological factors that can influence reinfection by S. mansoni one year after successful treatment with PZQ in school-aged children in Northeastern Minas …

Ancylostoma Ceylanicum Infective Third-Stage Larvae Are Activated By Co-Culture With Ht-29-Mtx Intestinal Epithelial Cells, Caitlin Feather, John M. Hawdon, John March

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Human hookworm larvae arrest development until they enter an appropriate host. This makes it difficult to access the larvae for studying larval development or host-parasite interactions. While there are in vivo and in vitro animal models of human hookworm infection, there is currently no human, in vitro model. While animal models have provided much insight into hookworm biology, there are limitations to how closely this can replicate human infection. Therefore, we have developed a human, in vitro model of the initial phase of hookworm infection using intestinal epithelial cell culture.

Results

Co-culture of the human hookworm Ancylostoma ceylanicum with …

Ebola Vp40 In Exosomes Can Cause Immune Cell Dysfunction, Michelle Pleet, Allison Mathiesen, Catherine Demarino, Yao Akpamagbo, Robert Barclay, Sergey N. Iordanskiy, +6 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Ebola virus (EBOV) is an enveloped, ssRNA virus from the family Filoviridae capable of causing severe hemorrhagic fever with up to 80–90% mortality rates. The most recent outbreak of EBOV in West Africa starting in 2014 resulted in over 11,300 deaths; however, long-lasting persistence and recurrence in survivors has been documented, potentially leading to further transmission of the virus. We have previously shown that exosomes from cells infected with HIV-1, HTLV-1 and Rift Valley Fever virus are able to transfer viral proteins and non-coding RNAs to naïve recipient cells, resulting in an altered cellular activity. In the current manuscript, we …

Transcriptomic Analysis Implicates The P53 Signaling Pathway In The Establishment Of Hiv-1 Latency In Central Memory Cd4 T Cells In An In Vitro Model, Cory White, Bastiaan Moesker, Nadejda Beliakova-Bethell, Laura Martins, Celsa Spina, Alberto Bosque, +4 Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The search for an HIV-1 cure has been greatly hindered by the presence of a viral reservoir that persists despite antiretroviral therapy (ART). Studies of HIV-1 latency in vivo are also complicated by the low proportion of latently infected cells in HIV-1 infected individuals. A number of models of HIV-1 latency have been developed to examine the signaling pathways and viral determinants of latency and reactivation. A primary cell model of HIV-1 latency, which incorporates the generation of primary central memory CD4 T cells (TCM), full-length virus infection (HIVNL4-3) and ART to suppress virus replication, was used to investigate the …

Antiviral Cd8(+) T Cells Restricted By Human Leukocyte Antigen Class Ii Exist During Natural Hiv Infection And Exhibit Clonal Expansion., Srinika Ranasinghe, Pedro A Lamothe, Damien Z Soghoian, Samuel W Kazer, Michael B Cole, Alex K Shalek, Nir Yosef, R. Brad Jones, Faith Donaghey, Chioma Nwonu, Priya Jani, Gina M Clayton, Frances Crawford, Janice White, Alana Montoya, Karen Power, Todd M Allen, Hendrik Streeck, Daniel E Kaufmann, Louis J Picker, John W Kappler, Bruce D Walker

Microbiology, Immunology, and Tropical Medicine Faculty Publications

CD8(+) T cell recognition of virus-infected cells is characteristically restricted by major histocompatibility complex (MHC) class I, although rare examples of MHC class II restriction have been reported in Cd4-deficient mice and a macaque SIV vaccine trial using a recombinant cytomegalovirus vector. Here, we demonstrate the presence of human leukocyte antigen (HLA) class II-restricted CD8(+) T cell responses with antiviral properties in a small subset of HIV-infected individuals. In these individuals, T cell receptor β (TCRβ) analysis revealed that class II-restricted CD8(+) T cells underwent clonal expansion and mediated killing of HIV-infected cells. In one case, these cells comprised 12% …

Hiv-1 Integrates Widely Throughout The Genome Of The Human Blood Fluke Schistosoma Mansoni., Sutas Suttiprapa, Gabriel Rinaldi, Isheng J Tsai, Victoria H. Mann, Larisa Dubrovsky, Hong-Bin Yan, Nancy Holroyd, Thomas Huckvale, Caroline Durrant, Anna V Protasio, Tatiana Pushkarsky, Sergey Iordanskiy, Matthew Berriman, Michael I. Bukrinsky, Paul J. Brindley

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the …

The Nih-Niaid Schistosomiasis Resource Center At The Biomedical Research Institute: Molecular Redux., James J Cody, Wannaporn Ittiprasert, André N Miller, Lucie Henein, Margaret M Mentink-Kane, Michael H. Hsieh

Urology Faculty Publications

Schistosomiasis remains a health burden in many parts of the world. The complex life cycle of Schistosoma parasites and the economic and societal conditions present in endemic areas make the prospect of eradication unlikely in the foreseeable future. Continued and vigorous research efforts must therefore be directed at this disease, particularly since only a single World Health Organization (WHO)-approved drug is available for treatment. The National Institutes of Health (NIH)-National Institute of Allergy and Infectious Diseases (NIAID) Schistosomiasis Resource Center (SRC) at the Biomedical Research Institute provides investigators with the critical raw materials needed to carry out this important research. …

The Global Economic And Health Burden Of Human Hookworm Infection., Sarah M Bartsch, Peter J. Hotez, Lindsey Asti, Kristina M Zapf, Maria Elena Bottazzi, David J. Diemert, Bruce Y Lee

Microbiology, Immunology, and Tropical Medicine Faculty Publications

BACKGROUND: Even though human hookworm infection is highly endemic in many countries throughout the world, its global economic and health impact is not well known. Without a better understanding of hookworm's economic burden worldwide, it is difficult for decision makers such as funders, policy makers, disease control officials, and intervention manufacturers to determine how much time, energy, and resources to invest in hookworm control.

METHODOLOGY/PRINCIPLE FINDINGS: We developed a computational simulation model to estimate the economic and health burden of hookworm infection in every country, WHO region, and globally, in 2016 from the societal perspective. Globally, hookworm infection resulted in …

Microfluidic Platform For Electrophysiological Recordings From Host-Stage Hookworm And Ascaris Suum Larvae: A New Tool For Anthelmintic Research, Janis Weeks, William Roberts, Kristin Robinson, Melissa Keaney, Jon Vermiere, Joseph Urban, Shawn Lockery, John M. Hawdon

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The screening of candidate compounds and natural products for anthelmintic activity is important for discovering new drugs against human and animal parasites. We previously validated in Caenorhabditis elegans a microfluidic device (‘chip’) that records non-invasively the tiny electrophysiological signals generated by rhythmic contraction (pumping) of the worm's pharynx. These electropharyngeograms (EPGs) are recorded simultaneously from multiple worms per chip, providing a medium-throughput readout of muscular and neural activity that is especially useful for compounds targeting neurotransmitter receptors and ion channels. Microfluidic technologies have transformedC. elegans research and the goal of the current study was to validate hookworm andAscaris …

Opisthorchiasis: An Overlooked Danger., Ludmila M Ogorodova, Olga S Fedorova, Banchob Sripa, Viatcheslav A Mordvinov, Aleksei V Katokhin, Jennifer Keiser, Peter Odermatt, Paul J. Brindley, Oleg A Mayboroda, Thirumalaisamy P Velavan, Maxim B Freidin, Alexey E Sazonov, Irina V Saltykova, Mariya Y Pakharukova, Yulia V Kovshirina, Kostas Kaloulis, Olga Y Krylova, Maria Yazdanbakhsh

Microbiology, Immunology, and Tropical Medicine Faculty Publications

No abstract provided.

Saccharomyces Boulardii And Bismuth Subsalicylate As Low-Cost Interventions To Reduce The Duration And Severity Of Cholera, Johnathan Sheele, Jessica Cartowski, Angela Dart, Arjun Poddar, Shikha Gupta, Ajay Gupta

Computer Science Faculty Publications

We conducted a randomised single-blinded clinical trial of 100 cholera patients in Port-au-Prince, Haiti to determine if the probiotic Saccharomyces cerevisiae var. boulardii and the anti-diarrhoeal drug bismuth subsalicylate (BS) were able to reduce the duration and severity of cholera. Subjects received either: S. boulardii 250 mg, S. boulardii 250 mg capsule plus BS 524 mg tablet, BS 524 mg, or two placebo capsules every 6 hours alongside standard treatment for cholera. The length of hospitalisation plus the number and volume of emesis, stool and urine were recorded every 6 hours until the study subject was discharged (n=83), left against …

Enhancement Of Disease And Pathology By Synergy Of Trichuris Suis And Campylobacter Jejuni In The Colon Of Immunologically Naive Swine, Linda S. Mansfield, David T. Gauthier, Sheila R. Abner, Kathryn M. Jones, Stacey R. Wilder, Joseph F. Urban

Biological Sciences Faculty Publications

Campylobacter jejuni, a leading cause of bacterial gastroenteritis, has different age distribution and disease expression in developing and developed countries, which may be due to the endemnicity of infection and the age of acquisition of immunity. Differences in disease expression are not solely dependent on the C jejuni strain or virulence attributes. Another modulating factor in developing countries may be endemic nematode infections such as Trichuris, which drive type 2 cytokine responses and down-regulate type I immune responses. In this study, three-day-old germfree pigs given dual infections with Trichuris suis and C jejuni had more frequent, more severe …