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Full-Text Articles in Medical Microbiology

Microbial Interactions Among Gardnerella, Prevotella And Fannyhessea Prior To Incident Bacterial Vaginosis: Protocol For A Prospective, Observational Study, Christina A. Muzny, Jacob H. Elnaggar, Lúcia G.V. Sousa, Ângela Lima, Kristal J. Aaron, Isaac C. Eastlund, Keonte J. Graves, Chaoling Dong, Olivia T. Van Gerwen, Meng Luo, Ashutosh Tamhane, Dustin Long, Nuno Cerca, Christopher M. Taylor Feb 2024

Microbial Interactions Among Gardnerella, Prevotella And Fannyhessea Prior To Incident Bacterial Vaginosis: Protocol For A Prospective, Observational Study, Christina A. Muzny, Jacob H. Elnaggar, Lúcia G.V. Sousa, Ângela Lima, Kristal J. Aaron, Isaac C. Eastlund, Keonte J. Graves, Chaoling Dong, Olivia T. Van Gerwen, Meng Luo, Ashutosh Tamhane, Dustin Long, Nuno Cerca, Christopher M. Taylor

School of Graduate Studies Faculty Publications

Introduction The aetiology of bacterial vaginosis (BV), a biofilm-associated vaginal infection, remains unknown. Epidemiologic data suggest that it is sexually transmitted. BV is characterised by loss of lactic acid-producing lactobacilli and an increase in facultative and strict anaerobic bacteria. Gardnerella spp are present in 95%–100% of cases; Gardnerella vaginalis has been found to be more virulent than other BV-associated bacteria (BVAB) in vitro. However, G. vaginalis is found in women with normal vaginal microbiota and colonisation is not sufficient for BV development. We hypothesise that Gardnerella spp initiate BV biofilm formation, but incident BV (iBV) requires incorporation of other key …


Autophagy And Cell Wall Integrity Pathways Coordinately Regulate The Development And Pathogenicity Through Moatg4 Phosphorylation In Magnaporthe Oryzae, Pusheng Guo, Yurong Wang, Jiayun Xu, Zhixiang Yang, Ziqi Zhang, Jinyi Qian, Jiexiong Hu, Ziyi Yin, Leiyun Yang, Muxing Liu, Xinyu Liu, Gang Li, Haifeng Zhang, Ryan Rumsey, Ping Wang, Zhengguang Zhang Jan 2024

Autophagy And Cell Wall Integrity Pathways Coordinately Regulate The Development And Pathogenicity Through Moatg4 Phosphorylation In Magnaporthe Oryzae, Pusheng Guo, Yurong Wang, Jiayun Xu, Zhixiang Yang, Ziqi Zhang, Jinyi Qian, Jiexiong Hu, Ziyi Yin, Leiyun Yang, Muxing Liu, Xinyu Liu, Gang Li, Haifeng Zhang, Ryan Rumsey, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

Autophagy and Cell wall integrity (CWI) signaling are critical stress-responsive processes during fungal infection of host plants. In the rice blast fungus Magnaporthe oryzae, autophagy-related (ATG) proteins phosphorylate CWI kinases to regulate virulence; however, how autophagy interplays with CWI signaling to coordinate such regulation remains unknown. Here, we have identified the phosphorylation of ATG protein MoAtg4 as an important process in the coordination between autophagy and CWI in M. oryzae. The ATG kinase MoAtg1 phosphorylates MoAtg4 to inhibit the deconjugation and recycling of the key ATG protein MoAtg8. At the same time, MoMkk1, a core kinase of CWI, also phosphorylates …


Targeted Repression Of Topa By Crispri Reveals A Critical Function For Balanced Dna Topoisomerase I Activity In The Chlamydia Trachomatis Developmental Cycle, Li Shen, Leiqiong Gao, Abigail R. Swoboda, Scot P. Ouellette Jan 2024

Targeted Repression Of Topa By Crispri Reveals A Critical Function For Balanced Dna Topoisomerase I Activity In The Chlamydia Trachomatis Developmental Cycle, Li Shen, Leiqiong Gao, Abigail R. Swoboda, Scot P. Ouellette

School of Medicine Faculty Publications

Chlamydia trachomatis is an obligate intracellular bacterium that is responsible for the most prevalent bacterial sexually transmitted infection. Changes in DNA topology in this pathogen have been linked to its pathogenicity-associated developmental cycle. Here, evidence is provided that the balanced activity of DNA topoisomerases contributes to controlling Chlamydia developmental processes. Utilizing catalytically inactivated Cas12 (dCas12)-based clustered regularly interspaced short palindromic repeats interference (CRISPRi) technology, we demonstrate targeted knockdown of chromosomal topA transcription in C. trachomatis without detected toxicity of dCas12. Repression of topA impaired the developmental cycle of C. trachomatis mostly through disruption of its differentiation from a replicative form …


Interplay Between Acetylation And Ubiquitination Of Imitation Switch Chromatin Remodeler Isw1 Confers Multidrug Resistance In Cryptococcus Neoformans, Yang Meng, Yue Ni, Zhuoran Li, Tianhang Jiang, Tianshu Sun, Yanjian Li, Xindi Gao, Hailong Li, Chenhao Suo, Chao Li, Sheng Yang, Tian Lan, Guojian Liao, Tongbao Liu, Ping Wang, Chen Ding Jan 2024

Interplay Between Acetylation And Ubiquitination Of Imitation Switch Chromatin Remodeler Isw1 Confers Multidrug Resistance In Cryptococcus Neoformans, Yang Meng, Yue Ni, Zhuoran Li, Tianhang Jiang, Tianshu Sun, Yanjian Li, Xindi Gao, Hailong Li, Chenhao Suo, Chao Li, Sheng Yang, Tian Lan, Guojian Liao, Tongbao Liu, Ping Wang, Chen Ding

School of Medicine Faculty Publications

Cryptococcus neoformans poses a threat to human health, but anticryptococcal therapy is hampered by the emergence of drug resistance, whose underlying mechanisms remain poorly understood. Herein, we discovered that Isw1, an imitation switch chromatin remodeling ATPase, functions as a master modulator of genes responsible for in vivo and in vitro multidrug resistance in C. neoformans. Cells with the disrupted ISW1 gene exhibited profound resistance to multiple antifungal drugs. Mass spectrometry analysis revealed that Isw1 is both acetylated and ubiquitinated, suggesting that an interplay between these two modification events exists to govern Isw1 function. Mutagenesis studies of acetylation and ubiquitination sites …


Genital Tract Infections, The Vaginal Microbiome And Gestational Age At Birth Among Pregnant Women In South Africa: A Cohort Study Protocol, Ranjana M.S. Gigi, Mandisa M. Mdingi, Hyunsul Jung, Shantelle Claassen-Weitz, Lukas Bütikofer, Jeffrey D. Klausner, Christina A. Muzny, Christopher M. Taylor, Janneke H.H.M. Van De Wijgert, Remco P.H. Peters, Nicola Low Dec 2023

Genital Tract Infections, The Vaginal Microbiome And Gestational Age At Birth Among Pregnant Women In South Africa: A Cohort Study Protocol, Ranjana M.S. Gigi, Mandisa M. Mdingi, Hyunsul Jung, Shantelle Claassen-Weitz, Lukas Bütikofer, Jeffrey D. Klausner, Christina A. Muzny, Christopher M. Taylor, Janneke H.H.M. Van De Wijgert, Remco P.H. Peters, Nicola Low

School of Medicine Faculty Publications

Introduction Preterm birth complications are the most common cause of death in children under 5 years. The presence of multiple microorganisms and genital tract inflammation could be the common mechanism driving early onset of labour. South Africa has high levels of preterm birth, genital tract infections and HIV infection among pregnant women. We plan to investigate associations between the presence of multiple lower genital tract microorganisms in pregnancy and gestational age at birth. Methods and analysis This cohort study enrols around 600 pregnant women at one public healthcare facility in East London, South Africa. Eligible women are ≥18 years and …


Association Of Chlamydia Trachomatis Burden With The Vaginal Microbiota, Bacterial Vaginosis, And Metronidazole Treatment, Caleb M. Ardizzone, Christopher M. Taylor, Evelyn Toh, Rebecca A. Lillis, Jacob H. Elnaggar, John W. Lammons, Patricia Dehon Mott, Emily L. Duffy, Li Shen, Alison J. Quayle Dec 2023

Association Of Chlamydia Trachomatis Burden With The Vaginal Microbiota, Bacterial Vaginosis, And Metronidazole Treatment, Caleb M. Ardizzone, Christopher M. Taylor, Evelyn Toh, Rebecca A. Lillis, Jacob H. Elnaggar, John W. Lammons, Patricia Dehon Mott, Emily L. Duffy, Li Shen, Alison J. Quayle

School of Graduate Studies Faculty Publications

Bacterial vaginosis (BV), a dysbiosis of the vaginal microbiota, is a common coinfection with Chlamydia trachomatis (Ct), and BV-associated bacteria (BVAB) and their products have been implicated in aiding Ct evade natural immunity. Here, we determined if a non-optimal vaginal microbiota was associated with a higher genital Ct burden and if metronidazole, a standard treatment for BV, would reduce Ct burden or aid in natural clearance of Ct infection. Cervicovaginal samples were collected from women at enrollment and, if testing positive for Ct infection, at a follow-up visit approximately one week later. Cervical Ct burden was assessed by inclusion forming …


Methionine Biosynthesis Enzyme Momet2 Is Required For Rice Blast Fungus Pathogenicity By Promoting Virulence Gene Expression Via Reducing 5mc Modification, Huimin Li, Pengcheng Mo, Jun Zhang, Zhuoer Xie, Xinyu Liu, Han Chen, Leiyun Yang, Muxing Liu, Haifeng Zhang, Ping Wang, Zhengguang Zhang Sep 2023

Methionine Biosynthesis Enzyme Momet2 Is Required For Rice Blast Fungus Pathogenicity By Promoting Virulence Gene Expression Via Reducing 5mc Modification, Huimin Li, Pengcheng Mo, Jun Zhang, Zhuoer Xie, Xinyu Liu, Han Chen, Leiyun Yang, Muxing Liu, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

The emergence of fungicide resistance severely threatens crop production by limiting the availability and application of established fungicides. Therefore, it is urgent to identify new fungicidal targets for controlling plant diseases. Here, we characterized the function of a conserved homoserine O-acetyltransferase (HOA) from the rice blast fungus Magnaporthe oryzae that could serve as the candidate antifungal target. Deletion of the MoMET2 and MoCYS2 genes encoding HOAs perturbed the biosynthesis of methionine and S-adenyl methionine, a methyl group donor for epigenetic modifications, and severely attenuated the development and virulence of M. oryzae. The ΔMomet2 mutant is significantly increased in 5-methylcytosine (5mC) …


Impact Of Testosterone Use On The Vaginal Microbiota Of Transgender Men, Including Susceptibility To Bacterial Vaginosis: Study Protocol For A Prospective, Observational Study, Christina A. Muzny, Olivia T. Van Gerwen, Julia A. Schroeder, Emma Sophia Kay-Duncan, Krishmita Siwakoti, Kristal J. Aaron, Isaac C. Eastlund, Keonte J. Graves, Jacob H. Elnaggar, Ashutosh Tamhane, Dustin Long, Nicholas Van Wagoner, Evelyn Toh, Christopher M. Taylor Mar 2023

Impact Of Testosterone Use On The Vaginal Microbiota Of Transgender Men, Including Susceptibility To Bacterial Vaginosis: Study Protocol For A Prospective, Observational Study, Christina A. Muzny, Olivia T. Van Gerwen, Julia A. Schroeder, Emma Sophia Kay-Duncan, Krishmita Siwakoti, Kristal J. Aaron, Isaac C. Eastlund, Keonte J. Graves, Jacob H. Elnaggar, Ashutosh Tamhane, Dustin Long, Nicholas Van Wagoner, Evelyn Toh, Christopher M. Taylor

School of Graduate Studies Faculty Publications

Introduction The effect of testosterone (T) therapy on the vaginal microbiota of transgender men (TGM) is not well characterised, although one cross-sectional study comparing the vaginal microbiota of cisgender women to TGM on T≥1 year found that, in 71% of the TGM, the vaginal microbiota was less likely to be Lactobacillus-dominated and more likely to be enriched with >30 other bacterial species, many associated with bacterial vaginosis (BV). This prospective study aims to investigate changes in the composition of the vaginal microbiota over time in TGM who retain their natal genitalia (ie, vagina) and initiate T. In addition, we will …


Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis Aug 2022

Infection And Transmission Determinants Of Flea-Borne Rickettsioses, Hanna J. Laukaitis

<strong> Theses and Dissertations </strong>

The genus Rickettsia is comprised of Gram-negative, obligate intracellular bacteria that are spread by hematophagous arthropods. Elucidating the factors conferring rickettsial virulence has perplexed investigators for decades, complicated by the lack of efficient genetic tools necessary to uncover rickettsial- and vector-specific factors contributing to persistence. The advent of transposon mutagenesis has enabled the field to make vast developments in uncovering novel rickettsial mechanisms utilized in various host backgrounds. Thus, the aim of this study was to generate Rickettsia felis transposon mutants and characterize novel phenotypes associated with genetic disruption in an arthropod background. Distribution of rickettsiae is reliant on the …


Solid-State Nmr Analysis Of Unlabeled Fungal Cell Walls From Aspergillus And Candida Species, Liyanage D. Fernando, Malitha C. Dickwella Widanage, S. Chandra Shekar, Frederic Mentink-Vigier, Ping Wang, Sungsool Wi, Tuo Wang Jul 2022

Solid-State Nmr Analysis Of Unlabeled Fungal Cell Walls From Aspergillus And Candida Species, Liyanage D. Fernando, Malitha C. Dickwella Widanage, S. Chandra Shekar, Frederic Mentink-Vigier, Ping Wang, Sungsool Wi, Tuo Wang

School of Medicine Faculty Publications

Fungal infections cause high mortality in immunocompromised individuals, which has emerged as a significant threat to human health. The efforts devoted to the development of antifungal agents targeting the cell wall polysaccharides have been hindered by our incomplete picture of the assembly and remodeling of fungal cell walls. High-resolution solid-state nuclear magnetic resonance (ss NMR) studies have substantially revised our understanding of the polymorphic structure of polysaccharides and the nanoscale organization of cell walls in Aspergillus fumigatus and multiple other fungi. However, this approach requires 13C/15N-enrichment of the sample being studied, severely restricting its application. Here we employ the dynamic …


Moerv29 Promotes Apoplastic Effector Secretion Contributing To Virulence Of The Rice Blast Fungus Magnaporthe Oryzae, Bin Qian, Xiaotong Su, Ziyuan Ye, Xinyu Liu, Muxing Liu, Danyu Shen, Han Chen, Haifeng Zhang, Ping Wang, Zhengguang Zhang Nov 2021

Moerv29 Promotes Apoplastic Effector Secretion Contributing To Virulence Of The Rice Blast Fungus Magnaporthe Oryzae, Bin Qian, Xiaotong Su, Ziyuan Ye, Xinyu Liu, Muxing Liu, Danyu Shen, Han Chen, Haifeng Zhang, Ping Wang, Zhengguang Zhang

School of Medicine Faculty Publications

During plant-pathogenic fungi and host plants interactions, numerous pathogen-derived proteins are secreted resulting in the activation of the unfolded protein response (UPR) pathway. For efficient trafficking of secretory proteins, including those important in disease progression, the cytoplasmic coat protein complex II (COPII) exhibits a multifunctional role whose elucidation remains limited. Here, we discovered that the COPII cargo receptor MoErv29 functions as a target of MoHac1, a previously identified transcription factor of the UPR pathway. In Magnaporthe oryzae, deletion of MoERV29 severely affected the vegetative growth, conidiation and biotrophic invasion of the fungus in susceptible rice hosts. We demonstrated that MoErv29 …


Chain-Selective Isotopic Labeling Of The Heterodimeric Type Iii Secretion Chaperone, Scc4:Scc1, Reveals The Total Structural Rearrangement Of The Chlamydia Trachomatis Bi-Functional Protein, Scc4, Thilini O. Ukwaththage, Samantha M. Keane, Li Shen, Megan A. Macnaughtan Oct 2020

Chain-Selective Isotopic Labeling Of The Heterodimeric Type Iii Secretion Chaperone, Scc4:Scc1, Reveals The Total Structural Rearrangement Of The Chlamydia Trachomatis Bi-Functional Protein, Scc4, Thilini O. Ukwaththage, Samantha M. Keane, Li Shen, Megan A. Macnaughtan

School of Medicine Faculty Publications

Scc4 is an unusual bi-functional protein from Chlamydia trachomatis (CT) that functions as a type III secretion system (T3SS) chaperone and an RNA polymerase (RNAP)-binding protein. Both functions require interactions with protein partners during specific stages of the CT developmental cycle. As a T3SS chaperone, Scc4 binds Scc1 during the late stage of development to form a heterodimer complex, which chaperones the essential virulence effector, CopN. During the early-middle stage of development, Scc4 regulates T3SS gene expression by binding the σ66-containing RNAP holoenzyme. In order to study the structure and association mechanism of the Scc4:Scc1 T3SS chaperone complex using nuclear …


Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding Aug 2020

Plasmodium Impairs Antibacterial Innate Immunity To Systemic Infections In Part Through Hemozoin-Bound Bioactive Molecules., Christopher Lynn Harding

Electronic Theses and Dissertations

Despite efforts to decrease the global health burden of malaria, infections with Plasmodium species continue to cause over 200 million episodes of malaria each year which resulted in 405,000 deaths in 2018 [1]. One complication of malaria is increased susceptibility to invasive bacterial infections. Plasmodium infections impair host immunity to non-Typhoid Salmonella (NTS) through activities of heme oxygenase I (HO-I) )-induced release of immature granulocytes and myeloid cell-derived IL-10. Yet, it is not known if these mechanisms are specific to NTS. We show here, that Plasmodium yoelii 17XNL (Py) infected mice had impaired clearance of systemic Listeria monocytogenes (Lm) during …


The Small Rna Complement Of Adult Schistosoma Haematobium., Andreas J Stroehlein, Neil D Young, Pasi K Korhonen, Ross S Hall, Aaron R Jex, Bonnie L Webster, David Rollinson, Paul J Brindley, Robin B Gasser May 2018

The Small Rna Complement Of Adult Schistosoma Haematobium., Andreas J Stroehlein, Neil D Young, Pasi K Korhonen, Ross S Hall, Aaron R Jex, Bonnie L Webster, David Rollinson, Paul J Brindley, Robin B Gasser

Microbiology, Immunology, and Tropical Medicine Faculty Publications

BACKGROUND: Blood flukes of the genus Schistosoma cause schistosomiasis-a neglected tropical disease (NTD) that affects more than 200 million people worldwide. Studies of schistosome genomes have improved our understanding of the molecular biology of flatworms, but most of them have focused largely on protein-coding genes. Small non-coding RNAs (sncRNAs) have been explored in selected schistosome species and are suggested to play essential roles in the post-transcriptional regulation of genes, and in modulating flatworm-host interactions. However, genome-wide small RNA data are currently lacking for key schistosomes including Schistosoma haematobium-the causative agent of urogenital schistosomiasis of humans.

METHODOLOGY: MicroRNAs (miRNAs) and other …


Drug Repurposing For Schistosomiasis: Combinations Of Drugs Or Biomolecules., Maria João Gouveia, Paul J Brindley, Fátima Gärtner, José M Correia Da Costa, Nuno Vale Feb 2018

Drug Repurposing For Schistosomiasis: Combinations Of Drugs Or Biomolecules., Maria João Gouveia, Paul J Brindley, Fátima Gärtner, José M Correia Da Costa, Nuno Vale

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Schistosomiasis is a major neglected tropical disease. Control of schistosomiasis currently relies on a single drug, praziquantel, and despite its efficacy against the all schistosome species that parasitize humans, it displays some problematic drawbacks and alone is ineffective in counteracting adverse pathologies associated with infection. Moreover, due to the development of the potential emergence of PZQ-resistant strains, the search for additional or alternative antischistosomal drugs have become a public health priority. The current drug discovery for schistosomiasis has been slow and uninspiring. By contrast, repurposing of existing approved drugs may offer a safe, rapid and cost-effective alternative. Combined treatment with …


Sertraline, Paroxetine, And Chlorpromazine Are Rapidly Acting Anthelmintic Drugs Capable Of Clinical Repurposing., Janis C Weeks, William M Roberts, Caitlyn Leasure, Brian M Suzuki, Kristin J Robinson, John M Hawdon, +Several Additional Authors Jan 2018

Sertraline, Paroxetine, And Chlorpromazine Are Rapidly Acting Anthelmintic Drugs Capable Of Clinical Repurposing., Janis C Weeks, William M Roberts, Caitlyn Leasure, Brian M Suzuki, Kristin J Robinson, John M Hawdon, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Parasitic helminths infect over 1 billion people worldwide, while current treatments rely on a limited arsenal of drugs. To expedite drug discovery, we screened a small-molecule library of compounds with histories of use in human clinical trials for anthelmintic activity against the soil nematode Caenorhabditis elegans. From this screen, we found that the neuromodulatory drugs sertraline, paroxetine, and chlorpromazine kill C. elegans at multiple life stages including embryos, developing larvae and gravid adults. These drugs act rapidly to inhibit C. elegans feeding within minutes of exposure. Sertraline, paroxetine, and chlorpromazine also decrease motility of adult Trichuris muris whipworms, prevent hatching …


Granulin Secreted By The Food-Borne Liver Fluke, Brandon Haugen, Shannon E Karinshak, Victoria H Mann, Anastas Popratiloff, Alex Loukas, Paul J Brindley, Michael J Smout Jan 2018

Granulin Secreted By The Food-Borne Liver Fluke, Brandon Haugen, Shannon E Karinshak, Victoria H Mann, Anastas Popratiloff, Alex Loukas, Paul J Brindley, Michael J Smout

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The liver fluke Opisthorchis viverrini is a food-borne, zoonotic pathogen endemic to Thailand and adjacent countries in Southeast Asia. The adult developmental stage of the O. viverrini parasite excretes and secretes numerous proteins within the biliary tract including the gall bladder. Lesions caused by the feeding activities of the liver fluke represent wounds that undergo protracted cycles of healing and re-injury during chronic infection, which can last for decades. Components of the excretory/secretory (ES) complement released by the worms capably drive proliferation of bile duct epithelial cells and are implicated in establishing the oncogenic milieu that leads to bile duct …


Granulin Secreted By The Food-Borne Liver Fluke Opisthorchis Viverrini Promotes Angiogenesis In Human Endothelial Cells, Brandon Haugen, Shannon Karinshak, Victoria H. Mann, Anastas Popratiloff, Alex Loukas, Paul J. Brindley, Michael J. Smout Jan 2018

Granulin Secreted By The Food-Borne Liver Fluke Opisthorchis Viverrini Promotes Angiogenesis In Human Endothelial Cells, Brandon Haugen, Shannon Karinshak, Victoria H. Mann, Anastas Popratiloff, Alex Loukas, Paul J. Brindley, Michael J. Smout

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The liver fluke Opisthorchis viverrini is a food-borne, zoonotic pathogen endemic to Thailand and adjacent countries in Southeast Asia. The adult developmental stage of the O. viverrini parasite excretes and secretes numerous proteins within the biliary tract including the gall bladder. Lesions caused by the feeding activities of the liver fluke represent wounds that undergo protracted cycles of healing and re-injury during chronic infection, which can last for decades. Components of the excretory/secretory (ES) complement released by the worms capably drive proliferation of bile duct epithelial cells and are implicated in establishing the oncogenic milieu that leads to bile duct …


Controlled Human Hookworm Infection: Accelerating Human Hookworm Vaccine Development, David Diemert, Doreen Campbell, Jill Brelsford, Caitlyn Leasure, Guangzhao Li, Naji Younes, +Several Additional Authors Jan 2018

Controlled Human Hookworm Infection: Accelerating Human Hookworm Vaccine Development, David Diemert, Doreen Campbell, Jill Brelsford, Caitlyn Leasure, Guangzhao Li, Naji Younes, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Controlled human hookworm infection (CHHI) is a central component of a proposed hookworm vaccination-challenge model (HVCM) to test the efficacy of candidate vaccines. Critical to CHHI is the manufacture of Necator americanus infective larvae (NaL3) according to current Good Manufacturing Practice (cGMP) and the determination of an inoculum of NaL3 that is safe and reliably induces patent infection. Methods

cGMP-grade NaL3 were produced for a phase 1 trial in 20 healthy, hookworm-naïve adults in the United States, who received either 25 or 50 NaL3. Participants were monitored for 12–18 weeks postinfection for safety, tolerability, …


Transplantation Of Schistosome Sporocysts Between Host Snails: A Video Guide., Gabriel Mouahid, Anne Rognon, Ronaldo De Carvalho Augusto, Patrick Driguez, Kathy Geyer, Shannon Karinshak, Nelia Luviano, Victoria Mann, Thomas Quack, Kate Rawlinson, George Wendt, Christoph Grunau, Hélène Moné Jan 2018

Transplantation Of Schistosome Sporocysts Between Host Snails: A Video Guide., Gabriel Mouahid, Anne Rognon, Ronaldo De Carvalho Augusto, Patrick Driguez, Kathy Geyer, Shannon Karinshak, Nelia Luviano, Victoria Mann, Thomas Quack, Kate Rawlinson, George Wendt, Christoph Grunau, Hélène Moné

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Schistosomiasis is an important parasitic disease, touching roughly 200 million people worldwide. The causative agents are different Schistosoma species. Schistosomes have a complex life cycle, with a freshwater snail as intermediate host. After infection, sporocysts develop inside the snail host and give rise to human dwelling larvae. We present here a detailed step-by-step video instruction in English, French, Spanish and Portuguese that shows how these sporocysts can be manipulated and transferred from one snail to another. This procedure provides a technical basis for different types of ex vivo modifications, such as those used in functional genomics studies.


Helminth Infection-Induced Malignancy., Paul J Brindley, Alex Loukas Jul 2017

Helminth Infection-Induced Malignancy., Paul J Brindley, Alex Loukas

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Infectious diseases cause more than 20% of cancers in the developing world [1]. About a dozen pathogens including Epstein-Barr virus and human T cell lymphocytotropic virus 1 are among the well-known examples. In addition, infection with several trematodes, which are eukaryotes, can cause malignancy. The International Agency for Research on Cancer categorizes infection with the fish-borne trematodes Opisthorchis viverrini and Clonorchis sinensis and the blood fluke Schistosoma haematobium as Group 1 biological carcinogens [2]. In addition to parasitism directly damaging development, health, and prosperity of infected populations, infection with these helminths leads to cholangiocarcinoma (CCA) (bile duct cancer) and squamous …


Subsets Of Inflammatory Cytokine Gene Polymorphisms Are Associated With Risk Of Carcinogenic Liver Fluke Opisthorchis Viverrini-Associated Advanced Periductal Fibrosis And Cholangiocarcinoma., Arpa Surapaitoon, Sutas Suttiprapa, Eimorn Mairiang, Narong Khuntikeo, Chawalit Pairojkul, Jeffrey Bethony, Paul J Brindley, Banchob Sripa Jun 2017

Subsets Of Inflammatory Cytokine Gene Polymorphisms Are Associated With Risk Of Carcinogenic Liver Fluke Opisthorchis Viverrini-Associated Advanced Periductal Fibrosis And Cholangiocarcinoma., Arpa Surapaitoon, Sutas Suttiprapa, Eimorn Mairiang, Narong Khuntikeo, Chawalit Pairojkul, Jeffrey Bethony, Paul J Brindley, Banchob Sripa

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Opisthorchis viverrini infection induces chronic inflammation, and a minor proportion of infected individuals develop advanced periductal fibrosis (APF) and cholangiocarcinoma (CCA). Inflammatory cytokines and/or their gene polymorphisms may link to these biliary pathologies. We therefore investigated associations among cytokine gene polymorphisms and cytokine production in 510 Thai cases infected with O. viverrini who presented with APF+ or APF−, as established by abdominal ultrasonography as well as in patients diagnosed with CCA. Levels of pro-inflammatory and anti-inflammatory cytokines were determined in culture supernatants after stimulation of peripheral blood mononuclear cells (PBMCs) with O. viverrini excretory-secretory (ES) products. Pro-inflammatory cytokines, IL-1β, IL-6, …


Whole Genome Analysis Of A Schistosomiasis-Transmitting Freshwater Snail., Coen M Adema, Ladeana W Hillier, Catherine S Jones, Eric S Loker, Matty Knight, Patrick Minx, +Several Additional Authors May 2017

Whole Genome Analysis Of A Schistosomiasis-Transmitting Freshwater Snail., Coen M Adema, Ladeana W Hillier, Catherine S Jones, Eric S Loker, Matty Knight, Patrick Minx, +Several Additional Authors

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Biomphalaria snails are instrumental in transmission of the human blood fluke Schistosoma mansoni. With the World Health Organization's goal to eliminate schistosomiasis as a global health problem by 2025, there is now renewed emphasis on snail control. Here, we characterize the genome of Biomphalaria glabrata, a lophotrochozoan protostome, and provide timely and important information on snail biology. We describe aspects of phero-perception, stress responses, immune function and regulation of gene expression that support the persistence of B. glabrata in the field and may define this species as a suitable snail host for S. mansoni. We identify …


Safety And Immunogenicity Of The Na-Gst-1 Hookworm Vaccine In Brazilian And American Adults., David J Diemert, Janaína Freire, Vanderson Valente, Carlos Geraldo Fraga, Frederico Talles, Shannon Grahek, Doreen Campbell, Amar Jariwala, Maria Victoria Periago, Martin Enk, Maria Flávia Gazzinelli, Maria Elena Bottazzi, Robert Hamilton, Jill Brelsford, Anna Yakovleva, Guangzhao Li, Jin Peng, Rodrigo Correa-Oliveira, Peter Hotez, Jeffrey Bethony May 2017

Safety And Immunogenicity Of The Na-Gst-1 Hookworm Vaccine In Brazilian And American Adults., David J Diemert, Janaína Freire, Vanderson Valente, Carlos Geraldo Fraga, Frederico Talles, Shannon Grahek, Doreen Campbell, Amar Jariwala, Maria Victoria Periago, Martin Enk, Maria Flávia Gazzinelli, Maria Elena Bottazzi, Robert Hamilton, Jill Brelsford, Anna Yakovleva, Guangzhao Li, Jin Peng, Rodrigo Correa-Oliveira, Peter Hotez, Jeffrey Bethony

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) plays a role in the digestion of host hemoglobin by adult N. americanus hookworms. Vaccination of laboratory animals with recombinant Na-GST-1 is associated with significant protection from challenge infection. Recombinant Na-GST-1 was expressed in Pichia pastoris and adsorbed to aluminum hydroxide adjuvant (Alhydrogel) according to current Good Manufacturing Practice. Two Phase 1 trials were conducted in 142 healthy adult volunteers in the United States and Brazil, first in hookworm-naïve individuals and then in residents of a N. americanus endemic area in Brazil. Volunteers received one of three doses of recombinant …


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 …


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 …


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 …