Parasitic Diseases Commons^™

Molecular Characterization Of A Tetraspanin From The Human Liver Fluke, Opisthorchis Viverrini, Supawadee Piratae, Smarn Tesana, Malcolm K. Jones, Paul J. Brindley, Alex Loukas, Erica Lovas, Veerachai Eursitthichai, Banchob Sripa, Sirikanda Thanasuwan, Thewarach Laha

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

The human liver fluke, Opisthorchis viverrini, is designated as a group 1 carcinogen, and is the major risk factor for cholangiocarcinoma in endemic countries throughout Southeast Asia. Proteins in the excretory-secretory products and tegumental surface membranes of the fluke have been proposed to play pivotal roles in parasite survival in the host, and subsequent pathogenesis. These macromolecules are therefore valid targets for the development of vaccines and new drugs to control the infection. Tetraspanins (TSP) are prominent components of the tegument of blood flukes where they are essential for tegument formation, are directly exposed to the immune system, …

Gastrointestinal Cell Mediated Immunity And The Microsporidia, Magali M. Moretto, Imtiaz A. Khan, Louis M. Weiss

Microbiology, Immunology, and Tropical Medicine Faculty Publications

No abstract provided.

Germline Transgenesis And Insertional Mutagenesis In Schistosoma Mansoni Mediated By Murine Leukemia Virus, Gabriel Rinaldi, Sabine E. Eckert, Isheng J. Tsai, Suttas Suttiprapa, Kristine J. Kines, Jose F. Tort, Victoria H. Mann, Daniel J. Turner, Matthew Berriman, Paul J. Brindley

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Functional studies will facilitate characterization of role and essentiality of newly available genome sequences of the human schistosomes, Schistosoma mansoni, S. japonicum and S. haematobium. To develop transgenesis as a functional approach for these pathogens, we previously demonstrated that pseudotyped murine leukemia virus (MLV) can transduce schistosomes leading to chromosomal integration of reporter transgenes and short hairpin RNA cassettes. Here we investigated vertical transmission of transgenes through the developmental cycle of S. mansoni after introducing transgenes into eggs. Although MLV infection of schistosome eggs from mouse livers was efficient in terms of snail infectivity, >10-fold higher transgene copy …

Vasa-Like Dead-Box Rna Helicases Of Schistosoma Mansoni, Danielle E. Skinner, Gabriel Rinaldi, Sutas Suttiprapa, Victoria H. Mann, Pablo Smircich, Alexis A. Cogswell, David L. Williams, Paul J. Brindley

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Genome sequences are available for the human blood flukes, Schistosoma japonicum, S. mansoni and S. haematobium. Functional genomic approaches could aid in identifying the role and importance of these newly described schistosome genes. Transgenesis is established for functional genomics in model species, which can lead to gain- or loss-of-functions, facilitate vector-based RNA interference, and represents an effective forward genetics tool for insertional mutagenesis screens. Progress toward routine transgenesis in schistosomes might be expedited if germ cells could be reliably localized in cultured schistosomes. Vasa, a member of the ATP-dependent DEAD-box RNA helicase family, is a prototypic marker of …

Elevated Plasma Il-6 Associates With Increased Risk Of Advanced Fibrosis And Cholangiocarcinoma In Individuals Infected By Opisthorchis Viverrini, Banchob Sripa, Bandit Thinkhamrop, Eimorn Mairiang, Thewarach Laha, Sasithorn Kaewkes, Paiboon Sithithaworn, Maria V. Periago, Vajarabhongsa Bhudhisawasdi, Ponlapat Yonglitthipagon, Jason Mulvenna, Paul J. Brindley, Alex Loukas, Jeffrey M. Bethony

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Opisthorchis viverrini is considered among the most important of the food-borne trematodes due to its strong association with advanced periductal fibrosis and bile duct cancer (cholangiocarcinoma). We investigated the relationship between plasma levels of Interleukin (IL)-6 and the risk of developing advanced fibrosis and bile duct cancer from chronic Opisthorchis infection. We show that IL-6 circulates in plasma at concentrations 58 times higher in individuals with advanced fibrosis than age, sex, and nearest-neighbor matched controls and 221 times higher in individuals with bile duct cancer than controls. We also observed a dose-response relationship between increasing levels of plasma IL-6 and …

Five-Year Longitudinal Assessment Of The Downstream Impact On Schistosomiasis Transmission Following Closure Of The Three Gorges Dam., Darren J. Gray, Aaron P. Thrift, Gail M. Williams, Feng Zheng, Yue-Sheng Li, Jiagang Guo, Honggen Chen, Tianping Wang, Xin J. Xu, Rong Zhu, Hongqing Zhu, Chun Li Cao, Dan D. Lin, Zhen Y. Zhao, Robert S. Li, George M. Davis, Donald P. Mcmanus

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Background

Schistosoma japonicum is a major public health concern in the Peoples' Republic of China (PRC), with about 800,000 people infected and another 50 million living in areas at risk of infection. Based on ecological, environmental, population genetic and molecular factors, schistosomiasis transmission in PRC can be categorised into four discrete ecosystems or transmission modes. It is predicted that, long-term, the Three Gorges Dam (TGD) will impact upon the transmission of schistosomiasis in the PRC, with varying degree across the four transmission modes.

Methodology/Principal Findings

We undertook longitudinal surveillance from 2002 to 2006 in sentinel villages of the three transmission …

Enhanced Protective Efficacy Of A Chimeric Form Of The Schistosomiasis Vaccine Antigen Sm-Tsp-2, Mark S. Pearson, Darren A. Pickering, Henry J. Mcsorley, Jeffrey M. Bethony, Leon Tribolet, Annette M. Dougall, Peter J. Hotez, Alex Loukas

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG1 and IgG3 from putatively resistant individuals resident in S. mansoniendemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to …

Characterising The Mucosal And Systemic Immune Responses To Experimental Human Hookworm Infection., Soraya Gaze, Henry J. Mcsorley, James Daveson, Di Jones, Jeffrey M. Bethony, Luciana M. Oliveira, Richard Speare, James S. Mccarthy, Christian R. Engwerda, John Croese, Alex Loukas

Microbiology, Immunology, and Tropical Medicine Faculty Publications

The mucosal cytokine response of healthy humans to parasitic helminths has never been reported. We investigated the systemic and mucosal cytokine responses to hookworm infection in experimentally infected, previously hookworm naive individuals from non-endemic areas. We collected both peripheral blood and duodenal biopsies to assess the systemic immune response, as well as the response at the site of adult worm establishment. Our results show that experimental hookworm infection leads to a strong systemic and mucosal Th2 (IL-4, IL-5, IL-9 and IL-13) and regulatory (IL-10 and TGF-β) response, with some evidence of a Th1 (IFN-γ and IL-2) response. Despite upregulation after …

Redefining Chronic Toxoplasmosis: A T Cell Exhaustion Perspective, Rajarshi Bhadra, Imtiaz A. Khan

Microbiology, Immunology, and Tropical Medicine Faculty Publications

No abstract provided.

Comparative Immunogenicity Of Na-Gst-1 Human Hookworm Vaccine With Synthetic Glucopyranosyl Lipid Adjuvant (Gla) In Balb/C Mice, Amar R. Jariwala, Brian Keegan, Jordan L. Plieskatt, Maria Elena Bottazzi, Peter J. Hotez, Jeffrey M. Bethony

Microbiology, Immunology, and Tropical Medicine Posters and Presentations

More than 740 million people worldwide are infected with Hookworm. Hookworm infection is most prevalent in the poorest of the poor populations of the world, and has serious health effects. Hookworm infection causes blood loss leading to iron deficiency anemia and protein energy malnutrition, which results in a compromised immune response. Consequently, the target human population suffers from an increased susceptibility to infectious diseases including hookworm infection. We have developed recombinant adult hookworm vaccines against hookworm infection to break this vicious cycle. Toll-like receptor (TLR) 4 agonist are known to boost immune response in healthy and immunocompromised individuals. We believe …

Campylobacter Ureolyticus: An Emerging Gastrointestinal Pathogen?, Susan Bullman, Daniel Corcoran, James O'Leary, Brigid Lucey, Deirdre Byrne, Roy D. Sleator

Department of Biological Sciences Publications

A total of 7194 faecal samples collected over a 1-year period from patients presenting with diarrhoea were screened for Campylobacter spp. using EntericBios, a multiplex-PCR system. Of 349 Campylobacter-positive samples, 23.8% were shown to be Campylobacter ureolyticus, using a combination of 16S rRNA gene analysis and highly specific primers targeting the HSP60 gene of this organism. This is, to the best of our knowledge, the first report of C. ureolyticus in the faeces of patients presenting with gastroenteritis and may suggest a role for this organism as an emerging enteric pathogen.

Lack Of Il-15 Results In The Suboptimal Priming Of Cd4+ T Cell Response Against An Intracellular Parasite, Crescent L. Combe, Magali M. Moretto, Joseph D. Schwartzman, Jason P. Gigley, David J. Bzik, Imtiaz A. Khan

Dartmouth Scholarship

IFN-gamma-producing CD4+ T cells, although important for protection against acute Toxoplasma gondii infection, can cause gut pathology, which may prove to be detrimental for host survival. Here we show that mice lacking IL-15 gene develop a down-regulated IFN-gamma-producing CD4+ T cell response against the parasite, which leads to a reduction in gut necrosis and increased level of survival against infection. Moreover, transfer of immune CD4+ T cells from WT to IL-15-/- mice reversed inhibition of gut pathology and caused mortality equivalent to levels of parental WT mice. Down-regulated CD4+ T cell response in the absence of IL-15, manifested as reduced …

Interleukin-17/Interleukin-17 Receptor-Mediated Signaling Is Important For Generation Of An Optimal Polymorphonuclear Response Against Toxoplasma Gondii Infection, Michelle N. Kelly, Jay K. Kolls, Kyle Happel, Joseph D. Schwartzman

Dartmouth Scholarship

We investigated the role of interleukin-17 (IL-17)/IL-17 receptor (IL-17R)-mediated signaling in the protective immunity against Toxoplasma gondii. IL-17R−/− mice developed a normal adaptive immunity against the parasite. However, increased mortality in the knockout animals can be attributed to a defect in the migration of polymorphonuclear leukocytes to infected sites during early infection.

Immune Responses Of Different Mouse Strains After Challenge With Equivalent Lethal Doses Of Toxoplasma Gondii, Y. H. Lee, L. H. Kasper

Dartmouth Scholarship

Most immunological studies that utilize different strains of inbred mice following T. gondii infection fail to compensate for differences in host susceptibility to the size of the parasite innoculum. To address this concern, susceptible C57BL/6 and resistant CBA/J mice were orally infected with either an equivalent 50 % lethal dose (LD₅₀) of brain cysts of the 76K strain of T. gondii (15 cysts in C57BL/6, 400 cysts in CBA/J) or the same dose of parasites in each mouse strain. C57BL/6 mice receiving 400 cysts (LD₅₀ of CBA/J mice) died post infection, whereas CBA/J mice that received 15 …

Attachment Of Toxoplasma Gondii To A Specific Membrane Fraction Of Cho Cells, Chaitali Dutta, Jane Grimwood, Lloyd H. Kasper

Dartmouth Scholarship

We have observed previously that attachment of Toxoplasma gondii to synchronized host cells is considerably increased at the mid-S phase (4 h postrelease). Synchronized CHO host cells at the mid-S phase were fractionated by molecular weight, and the antigens were used to produce a panel of polyclonal mouse antisera. The polyclonal antisera raised against fraction 4 with molecular mass ranging approximately from 18 to 40 kDa significantly reduced attachment to mid-S-phase host cells. Immunofluorescence assays demonstrated strong reactivity to mid-S-phase host cells and identified a number of potential receptors on Western blots. These data indicate that there is a specific …

Lack Of Cd4+ T Cells Does Not Affect Induction Of Cd8+ T-Cell Immunity Against Encephalitozoon Cuniculi Infection, Magali Moretto, Lori Casciotti, Brigit Durell, Imtiaz A. Khan

Dartmouth Scholarship

Cell-mediated immunity has been reported to play an important role in defense against Encephalitozoon cuniculi infection. Previous studies from our laboratory have underlined the importance of cytotoxic CD8⁺ T lymphocytes (CTL) in survival of mice infected with E. cuniculi. In the present study, immune response against E. cuniculi infection in CD4⁺T-cell-deficient mice was evaluated. Similar to resistant wild-type animals, CD4^−/− mice were able to resolve E. cuniculi infection even at a very high challenge dose (5 × 10⁷ spores/mouse). Tissues from infected CD4^−/−mice did not exhibit higher parasite loads in comparison to …

Differential Infectivity And Division Of Toxoplasma Gondii In Human Peripheral Blood Leukocytes, Jacqueline Y. Channon, Rosanne M. Seguin, Lloyd H. Kasper

Dartmouth Scholarship

When tachyzoites were incubated with human peripheral blood leukocytes in vitro, more monocytes and dendritic cells than neutrophils or lymphocytes were infected. Although tachyzoites were able to divide in each of these cell types, monocytes and dendritic cells were more permissive to rapid tachyzoite division than neutrophils or lymphocytes.

Immune Responses Induced By Gene Gun Or Intramuscular Injection Of Dna Vaccines That Express Immunogenic Regions Of The Serine Repeat Antigen From Plasmodium Falciparum, Alexia A. Belperron, David Feltquate, Barbara A. Fox, Toshihiro Horii, David J. Bzik

Dartmouth Scholarship

The liver- and blood-stage-expressed serine repeat antigen (SERA) of Plasmodium falciparum is a candidate protein for a human malaria vaccine. We compared the immune responses induced in mice immunized with SERA-expressing plasmid DNA vaccines delivered by intramuscular (i.m.) injection or delivered intradermally by Gene Gun immunization. Mice were immunized with a pcdna3 plasmid encoding the entire 47-kDa domain of SERA (amino acids 17 to 382) or the N-terminal domain (amino acids 17 to 110) of SERA. Minimal antibody responses were detected following DNA vaccination with the N-terminal domain of SERA, suggesting that the N-terminal domain alone is not highly immunogenic …

Attachment Ligands Of Viable Toxoplasma Gondii Induce Soluble Immunosuppressive Factors In Human Monocytes, Jacqueline Y. Channon, Edward I. Suh, Rosanne M. Seguin, Lloyd H. Kasper

Dartmouth Scholarship

Previous studies have demonstrated that surface antigen proteins, in particular SAG-1, of Toxoplasma gondii are important to this parasite as attachment ligands for the host cell. An in vitro assay was developed to test whether these ligands and other secretory proteins are involved in the immune response of human cells to toxoplasma. Human monocytes were infected with tachyzoites in the presence of antiparasite antibodies, and their effect on mitogen-induced lymphoproliferation was examined. The presence of antibody to either parasite-excreted proteins (MIC-1 and MIC-2) or surface proteins (SAG-1 and SAG-2) during infection neutralized the marked decrease seen in mitogen-induced lymphoproliferation in …

Role Of Gamma Interferon In Cellular Immune Response Against Murine Encephalitozoon Cuniculi Infection, Imtiaz A. Khan, Magali Moretto

Dartmouth Scholarship

Microsporidia are obligate intracellular protozoan parasites that cause a wide variety of opportunistic infection in patients with AIDS. Because it is able to grow in vitro, Encephalitozoon cuniculi is currently the best-studied microsporidian. T cells mediate protective immunity against this parasite. Splenocytes obtained from infected mice proliferate in vitro in response to irradiated parasites. A transient state of hyporesponsiveness to parasite antigen and mitogen was observed at day 17 postinfection. This downregulatory response could be partially reversed by addition of nitric oxide (NO) antagonist to the culture. Mice infected withE. cuniculi secrete significant levels of gamma interferon (IFN-γ). Treatment …

Fas-Fasl Interaction Involved In Pathogenesis Of Ocular Toxoplasmosis In Mice, Mark S. Hu, Joseph D. Schwartzman, Grant R. Yeaman, Jane Collins, Rosanne Seguin, Imtiaz A. Khan, Lloyd H. Kasper

Dartmouth Scholarship

Ocular toxoplasmosis is a potentially blinding intraocular inflammation. The intent of this study was to investigate the role of Fas-FasL interaction in a murine model of acquired ocular toxoplasmosis induced by intracameral inoculation of Toxoplasma gondii. Intraocular inflammation, Fas and FasL expression on lymphocytes and on ocular tissues, the occurrence of apoptosis, and the frequency of CD8⁺ and CD4⁺ T cells in the infected eyes were analyzed in C57BL/6 (B6) mice. Susceptibility to parasite-induced intraocular inflammation was observed in Fas-deficient (B6-lpr) and FasL-deficient (B6-gld) mice. Inoculation of 5,000 T. gondii tachyzoites induced significant …

Antigen-Specific Cd8+ T Cells Protect Against Lethal Toxoplasmosis In Mice Infected With Neospora Caninum, Lloyd H. Kasper, Imtiaz A. Khan

Dartmouth Scholarship

Neospora caninum is a coccidial protozoan parasite that appears morphologically indistinguishable from Toxoplasma gondii and that infects a large range of mammals. Both inbred and outbred strains of mice exhibit a high degree of resistance to infection with N. caninum. Three inbred strains of mice (A/J, BALB/c, and C57BL/6) that were infected intraperitoneally with N. caninum were protected against a lethal challenge from T. gondii. Vaccine-induced protection was Neospora dose dependent. A rise in the CD8+ T-cell population in mice that had been vaccinated with N. caninum and challenged with T. gondii was observed. Adoptive transfer of CD8+ T-cell splenocytes …

Attachment Of Toxoplasma Gondii To Host Cells Is Host Cell Cycle Dependent., Jane Grimwood, Jose R. Mineo, Lloyd H. Kasper

Dartmouth Scholarship

The initial attachment of Toxoplasma tachyzoites to target host cells is an important event in the life cycle of the parasite and hence critical in the pathogenesis of this infection. The efficiency of Toxoplasma attachment to synchronized populations of Chinese hamster ovary cells and bovine kidney cells was investigated by using a glutaraldehyde-fixed host cell assay system. For both cell lines, parasite attachment increased as the synchronized host cells proceeded from the G1 phase to the mid-S phase and then decreased as the cells entered the G2-M boundary. Postulating that these differences in attachment reflect the upregulation of a specific …

Murine Gamma Interferon Fails To Inhibit Toxoplasma Gondii Growth In Murine Fibroblasts., Joseph D. Schwartzman, Steven L. Gonias, E R. Pfefferkorn

Dartmouth Scholarship

Although treatment of human macrophages or fibroblasts with human gamma interferon results in the inhibition of intracellular Toxoplasma gondii, murine gamma interferon stimulated only murine macrophages, not murine fibroblasts, to inhibit T. gondii. This species difference may be important in understanding the control of acute and chronic toxoplasmosis.