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Full-Text Articles in Medical Specialties

Dynamic Transcriptomes Identify Biogenic Amines And Insect-Like Hormonal Regulation For Mediating Reproduction In Schistosoma Japonicum., Jipeng Wang, Ying Yu, Haimo Shen, Tao Qing, Yuanting Zheng, Qing Li, Xiaojin Mo, Shuqi Wang, Nana Li, Riyi Chai, Bin Xu, Mu Liu, Paul J Brindley, Donald P Mcmanus, Zheng Feng, Leming Shi, Wei Hu Mar 2017

Dynamic Transcriptomes Identify Biogenic Amines And Insect-Like Hormonal Regulation For Mediating Reproduction In Schistosoma Japonicum., Jipeng Wang, Ying Yu, Haimo Shen, Tao Qing, Yuanting Zheng, Qing Li, Xiaojin Mo, Shuqi Wang, Nana Li, Riyi Chai, Bin Xu, Mu Liu, Paul J Brindley, Donald P Mcmanus, Zheng Feng, Leming Shi, Wei Hu

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Eggs produced by the mature female parasite are responsible for the pathogenesis and transmission of schistosomiasis. Female schistosomes rely on a unique male-induced strategy to accomplish reproductive development, a process that is incompletely understood. Here we map detailed transcriptomic profiles of male and female Schistosoma japonicum across eight time points throughout the sexual developmental process from pairing to maturation. The dynamic gene expression pattern data reveal clear sex-related characteristics, indicative of an unambiguous functional division between males and females during their interplay. Cluster analysis, in situ hybridization and RNAi assays indicate that males likely use biogenic amine neurotransmitters through the …


The Role Of Estradiol Metabolism In Urogenital Schistosomiasis-Induced Bladder Cancer, Nuno Vale, Maria Gouveia, Gabriel Rinaldi, Julio Santos, Lucio Lara Santos, Paul J. Brindley, Jose Correia Da Costa Mar 2017

The Role Of Estradiol Metabolism In Urogenital Schistosomiasis-Induced Bladder Cancer, Nuno Vale, Maria Gouveia, Gabriel Rinaldi, Julio Santos, Lucio Lara Santos, Paul J. Brindley, Jose Correia Da Costa

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Urogenital schistosomiasis is a neglected tropical disease that can lead to bladder cancer. How urogenital schistosomiasis induces carcinogenesis remains unclear, although there is evidence that the human blood fluke Schistosoma haematobium, the infectious agent of urogenital schistosomiasis, releases estradiol-like metabolites. These kind of compounds have been implicated in other cancers. Aiming for enhanced understanding of the pathogenesis of the urogenital schistosomiasisinduced bladder cancer, here we review, interpret, and discuss findings of estradiol-like metabolites detected in both the parasite and in the human urine during urogenital schistosomiasis. Moreover, we predict pathways and enzymes that are involved in the production of these …


Elevated Prevalence Of Helicobacter Species And Virulence Factors In Opisthorchiasis And Associated Hepatobiliary Disease., Raksawan Deenonpoe, Eimorn Mairiang, Pisaln Mairiang, Chawalit Pairojkul, Yaovalux Chamgramol, Gabriel Rinaldi, Alex Loukas, Paul J. Brindley, Banchob Sripa Feb 2017

Elevated Prevalence Of Helicobacter Species And Virulence Factors In Opisthorchiasis And Associated Hepatobiliary Disease., Raksawan Deenonpoe, Eimorn Mairiang, Pisaln Mairiang, Chawalit Pairojkul, Yaovalux Chamgramol, Gabriel Rinaldi, Alex Loukas, Paul J. Brindley, Banchob Sripa

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Recent reports suggest that Opisthorchis viverrini serves as a reservoir of Helicobacter and implicate Helicobacter in pathogenesis of opisthorchiasis-associated cholangiocarcinoma (CCA). Here, 553 age-sex matched cases and controls, 293 and 260 positive and negative for liver fluke O. viverrini eggs, of residents in Northeastern Thailand were investigated for associations among infection with liver fluke, Helicobacter and hepatobiliary fibrosis. The prevalence of H. pylori infection was higher in O. viverrini-infected than uninfected participants. H. pylori bacterial load correlated positively with intensity of O. viverrini infection, and participants with opisthorchiasis exhibited higher frequency of virulent cagA-positive H. pylori than those free of …


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 Feb 2017

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 Feb 2017

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 Feb 2017

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 Jan 2017

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 Jan 2017

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 …


A Fashi Lymphoproliferative Phenotype Reveals Non-Apoptotic Fas Signalling In Htlv-1-Associated Neuroinflammation., Soraya Maria Menezes, Fabio E Leal, Tim Dierckx, Ricardo Khouri, Daniele Decanine, Gilvaneia Silva-Santos, +Several Additional Authors Jan 2017

A Fashi Lymphoproliferative Phenotype Reveals Non-Apoptotic Fas Signalling In Htlv-1-Associated Neuroinflammation., Soraya Maria Menezes, Fabio E Leal, Tim Dierckx, Ricardo Khouri, Daniele Decanine, Gilvaneia Silva-Santos, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Human T-cell lymphotropic virus (HTLV)-1 was the first human retrovirus to be associated to cancer, namely Adult T-cell Leukemia (ATL), but its pathogenesis remains enigmatic, since only a minority of infected individuals develops either ATL or the neuroinflammatory disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A functional FAS -670 polymorphism in an interferon (IFN)-regulated STAT1-binding site has been associated to both ATL and HAM/TSP susceptibility. Fashi T stem cell memory (Tscm) cells have been identified as the hierarchical apex of ATL, but have not been investigated in HAM/TSP. In addition, both FAS and STAT1 have been identified in an IFN-inducible HAM/TSP …


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 Jan 2017

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. …


Mait Cells Are Reduced In Frequency And Functionally Impaired In Human T Lymphotropic Virus Type 1 Infection: Potential Clinical Implications., Dominic Paquin-Proulx, Benjamin C Greenspun, Emanuela A S Costa, Aluisio C Segurado, Esper G Kallas, Douglas F Nixon, Fabio E Leal Jan 2017

Mait Cells Are Reduced In Frequency And Functionally Impaired In Human T Lymphotropic Virus Type 1 Infection: Potential Clinical Implications., Dominic Paquin-Proulx, Benjamin C Greenspun, Emanuela A S Costa, Aluisio C Segurado, Esper G Kallas, Douglas F Nixon, Fabio E Leal

Microbiology, Immunology, and Tropical Medicine Faculty Publications

HTLV-1 infection is associated with several inflammatory disorders, including the neurodegenerative condition HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). It is unclear why a minority of infected subjects develop HAM/TSP. The cellular immune response has been implicated in the development of inflammatory alterations in these patients; however the pathogenic mechanisms for disease progression remain unclear. Furthermore, HTLV-1-infected individuals have an increase incidence of Mycobacterium tuberculosis (Mtb) infection, suggesting that immunological defect are associated with HTLV-1 infection. Evidence suggests an important role for Mucosal-associated invariant T (MAIT) cells in the early control of Mtb infection. Chronic viral infections like HIV and HCV have …


The Herpevac Trial For Women: Sequence Analysis Of Glycoproteins From Viruses Obtained From Infected Subjects., Miguel A Minaya, Maria Korom, Hong Wang, Robert B Belshe, Lynda A Morrison Jan 2017

The Herpevac Trial For Women: Sequence Analysis Of Glycoproteins From Viruses Obtained From Infected Subjects., Miguel A Minaya, Maria Korom, Hong Wang, Robert B Belshe, Lynda A Morrison

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The Herpevac Trial for Women revealed that three dose HSV-2 gD vaccine was 58% protective against culture-positive HSV-1 genital disease, but it was not protective against HSV-2 infection or disease. To determine whether vaccine-induced immune responses had selected for a particular gD sequence in strains infecting vaccine recipients compared with viruses infecting control subjects, genetic sequencing studies were carried out on viruses isolated from subjects infected with HSV-1 or HSV-2. We identified naturally occurring variants among the gD sequences obtained from 83 infected subjects. Unique or low frequency amino acid substitutions in the ectodomain of gD were found in 6 …


T-Cell Responses In Individuals Infected With Zika Virus And In Those Vaccinated Against Dengue Virus, Dominic Paquin-Proulx, Douglas F. Nixon, +Several Additional Authors Jan 2017

T-Cell Responses In Individuals Infected With Zika Virus And In Those Vaccinated Against Dengue Virus, Dominic Paquin-Proulx, Douglas F. Nixon, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background: The outbreak of Zika virus (ZIKV) infection in Brazil has raised concerns that infection during pregnancy could cause microcephaly and other severe neurodevelopmental malformations in the fetus. The mechanisms by which ZIKV causes fetal abnormalities are largely unknown. The importance of pre-infection with dengue virus (DENV), or other flaviviruses endemic to Brazil, remains to be investigated. It has been reported that antibodies directed against DENV can increase ZIKV infectivity by antibody dependent enhancement (ADE), suggesting that a history of prior DENV infection might worsen the outcome of ZIKV infection.

Methods: We used bioinformatics tools to design 18 peptides from …


Inhibiting Dna Methylation Activates Cancer Testis Antigens And Expression Of The Antigen Processing And Presentation Machinery In Colon And Ovarian Cancer Cells., Cornelia Siebenkäs, Katherine B Chiappinelli, Angela A Guzzetta, Anup Sharma, Jana Jeschke, Rajita Vatapalli, Stephen B Baylin, Nita Ahuja Jan 2017

Inhibiting Dna Methylation Activates Cancer Testis Antigens And Expression Of The Antigen Processing And Presentation Machinery In Colon And Ovarian Cancer Cells., Cornelia Siebenkäs, Katherine B Chiappinelli, Angela A Guzzetta, Anup Sharma, Jana Jeschke, Rajita Vatapalli, Stephen B Baylin, Nita Ahuja

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Innovative therapies for solid tumors are urgently needed. Recently, therapies that harness the host immune system to fight cancer cells have successfully treated a subset of patients with solid tumors. These responses have been strong and durable but observed in subsets of patients. Work from our group and others has shown that epigenetic therapy, specifically inhibiting the silencing DNA methylation mark, activates immune signaling in tumor cells and can sensitize to immune therapy in murine models. Here we show that colon and ovarian cancer cell lines exhibit lower expression of transcripts involved in antigen processing and presentation to immune cells …


Enriched Environment And Stress Exposure Influence Splenic B Lymphocyte Composition., Blake T Gurfein, Burcu Hasdemir, Jeffrey M Milush, Chadi Touma, Rupert Palme, Douglas F Nixon, Nicholas Darcel, Frederick M Hecht, Aditi Bhargava Jan 2017

Enriched Environment And Stress Exposure Influence Splenic B Lymphocyte Composition., Blake T Gurfein, Burcu Hasdemir, Jeffrey M Milush, Chadi Touma, Rupert Palme, Douglas F Nixon, Nicholas Darcel, Frederick M Hecht, Aditi Bhargava

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Prolonged chronic stress has deleterious effects on immune function and is associated with numerous negative health outcomes. The spleen harbors one-fourth of the body’s lymphocytes and mediates both innate and adaptive immune responses. However, the subset of splenic lymphocytes that respond, either adaptively or maladaptively, to various stressors remains largely unknown. Here we investigated the effects of unpredictable chronic mild stress (CMS) exposure on spleen composition in male mice housed in two different caging conditions: standard caging (Cntl) and enriched environment (EE). EE-caged mice exhibited the greatest absolute number of splenocytes and CMS exposure significantly lowered splenocyte numbers in both …


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 Jan 2017

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 …


A Modified Fasp Protocol For High-Throughput Preparation Of Protein Samples For Mass Spectrometry., Jeremy Potriquet, Marut Laohaviroj, Jeffrey M Bethony, Jason Mulvenna Jan 2017

A Modified Fasp Protocol For High-Throughput Preparation Of Protein Samples For Mass Spectrometry., Jeremy Potriquet, Marut Laohaviroj, Jeffrey M Bethony, Jason Mulvenna

Microbiology, Immunology, and Tropical Medicine Faculty Publications

o facilitate high-throughput proteomic analyses we have developed a modified FASP protocol which improves the rate at which protein samples can be processed prior to mass spectrometry. Adapting the original FASP protocol to a 96-well format necessitates extended spin times for buffer exchange due to the low centrifugation speeds tolerated by these devices. However, by using 96-well plates with a more robust polyethersulfone molecular weight cutoff membrane, instead of the cellulose membranes typically used in these devices, we could use isopropanol as a wetting agent, decreasing spin times required for buffer exchange from an hour to 30 minutes. In a …


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 Jan 2017

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 …


Mycobacterium Tuberculosis Reactivates Latent Hiv-1 In T Cells In Vitro, Erica Larson, Camille Novis, Laura Martins, Amanda Macedo, Kadyn Kimball, Alberto Bosque, Vincent Planelles, Louis Barrows Jan 2017

Mycobacterium Tuberculosis Reactivates Latent Hiv-1 In T Cells In Vitro, Erica Larson, Camille Novis, Laura Martins, Amanda Macedo, Kadyn Kimball, Alberto Bosque, Vincent Planelles, Louis Barrows

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Following proviral integration into the host cell genome and establishment of a latent state, the human immunodeficiency virus type 1 (HIV-1) can reenter a productive life cycle in response to various stimuli. HIV-1 reactivation occurs when transcription factors, such as nuclear factor-κB (NF-κB), nuclear factor of activated T cells (NFAT), and activator protein -1 (AP-1), bind cognate sites within the long terminal repeat (LTR) region of the HIV-1 provirus to promote transcription. Interestingly, pattern recognition receptors (PRRs) that recognize pathogen-associated molecular patterns (PAMPs) can reactivate latent HIV-1 through activation of the transcription factor NF-κB. Some PRRs are expressed on central …


Downregulated Il-21 Response And T Follicular Helper Cell Exhaustion Correlate With Compromised Cd8 T Cell Immunity During Chronic Toxoplasmosis, Magali M. Moretto, Sujin Hwang, Imtiaz A. Khan Jan 2017

Downregulated Il-21 Response And T Follicular Helper Cell Exhaustion Correlate With Compromised Cd8 T Cell Immunity During Chronic Toxoplasmosis, Magali M. Moretto, Sujin Hwang, Imtiaz A. Khan

Microbiology, Immunology, and Tropical Medicine Faculty Publications

CD8 T cells are important for maintaining the chronicity of Toxoplasma gondii infection. In a T. gondii encephalitis susceptible model, we recently demonstrated that CD4 T cells play an essential helper role in the maintenance of the effector response and CD8 T cell dysfunctionality was linked to CD4 T cell exhaustion. However, CD4 T cells are constituted of different subsets with various functions and the population(s) providing help to the CD8 T cells has not yet been determined. In the present study, Tfh cells (T follicular helper), which are known to be essential for B cell maturation and are one …


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 Jan 2017

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 …


Severe Mortality Impact Of The 1957 Influenza Pandemic In Chile., Gerardo Chowell, Lone Simonsen, Rodrigo Fuentes, Jose Flores, Mark A Miller, Cécile Viboud Nov 2016

Severe Mortality Impact Of The 1957 Influenza Pandemic In Chile., Gerardo Chowell, Lone Simonsen, Rodrigo Fuentes, Jose Flores, Mark A Miller, Cécile Viboud

Microbiology, Immunology, and Tropical Medicine Faculty Publications

INTRODUCTION: Epidemiological studies of the 1957 influenza pandemic are scarce, particularly from lower-income settings.

METHODS: We analyzed the spatial-temporal mortality patterns of the 1957 influenza pandemic in Chile, including detailed age-specific mortality data from a large city, and investigated risk factors for severe mortality impact across regions.

RESULTS: Chile exhibited two waves of excess mortality in winter 1957 and 1959 with a cumulative excess mortality rate of 12 per 10 000, and a ~10-fold mortality difference across provinces. High excess mortality rates were associated with high baseline mortality (R(2) =41.8%; P=.02), but not with latitude (P>.7). Excess mortality rates …


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 Nov 2016

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 Nov 2016

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 Oct 2016

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 Oct 2016

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 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 Sep 2016

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 Sep 2016

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 …


Brief Report: Hiv-1 Gp120 T-Cell Responses Correspond To Infection Outcomes In The Global Iprex Chemoprophylaxis Trial., Peter J Kuebler, Brian I Shaw, Kaitlyn S Leadabrand, Megha L Mehrotra, Robert M Grant, Esper G Kallás, Douglas F Nixon Jun 2016

Brief Report: Hiv-1 Gp120 T-Cell Responses Correspond To Infection Outcomes In The Global Iprex Chemoprophylaxis Trial., Peter J Kuebler, Brian I Shaw, Kaitlyn S Leadabrand, Megha L Mehrotra, Robert M Grant, Esper G Kallás, Douglas F Nixon

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Association of HIV-1-specific T-cell responses to infection risk in seronegative individuals is controversial. We quantified and phenotypically characterized gp120-specific T-cell responses in HIV-1 exposed, but uninfected subjects enrolled in the global Pre-exposure Prophylaxis Initiative (iPrEx) chemoprophylaxis trial. IFNγ ELISpot responses were detected in 24% of subjects irrespective of infection outcome. HIV-1 gp120 envelope-specific T-cell responses were more uniformly IFN-γ+TNF-α+Mip-1β+ in persistently seronegative subjects relative to subjects who later seroconverted (median frequency of 76.5% and 66.5%, respectively). IFNγ responses targeted the V2 loop for subjects who remained seronegative. HIV-1 gp120 envelope V2 loop-specific CD8 T-cell responses may help to protect against …


A Conserved Dna Repeat Promotes Selection Of A Diverse Repertoire Of Trypanosoma Brucei Surface Antigens From The Genomic Archive., Galadriel Hovel-Miner, Monica R Mugnier, Benjamin Goldwater, George A M Cross, F Nina Papavasiliou May 2016

A Conserved Dna Repeat Promotes Selection Of A Diverse Repertoire Of Trypanosoma Brucei Surface Antigens From The Genomic Archive., Galadriel Hovel-Miner, Monica R Mugnier, Benjamin Goldwater, George A M Cross, F Nina Papavasiliou

Microbiology, Immunology, and Tropical Medicine Faculty Publications

African trypanosomes are mammalian pathogens that must regularly change their protein coat to survive in the host bloodstream. Chronic trypanosome infections are potentiated by their ability to access a deep genomic repertoire of Variant Surface Glycoprotein (VSG) genes and switch from the expression of one VSG to another. Switching VSG expression is largely based in DNA recombination events that result in chromosome translocations between an acceptor site, which houses the actively transcribed VSG, and a donor gene, drawn from an archive of more than 2,000 silent VSGs. One element implicated in these duplicative gene conversion events is a DNA repeat …