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Lichtenbergová L, Lassmann H, Jones MK, Kolářová L, Horák P. Trichobilharzia regenti: host immune response in the pathogenesis of neuroinfection in mice. Exp Parasitol 2011; 128:328-35. [PMID: 21554878 DOI: 10.1016/j.exppara.2011.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 04/18/2011] [Accepted: 04/26/2011] [Indexed: 10/18/2022]
Abstract
Besides their natural bird hosts, Trichobilharzia regenti cercariae are able to penetrate skin of mammals, including humans. Experimental infections of mice showed that schistosomula of this species are able to avoid the immune response in skin of their non-specific mammalian host and escape the skin to migrate to the CNS. Schistosomula do not mature in mammals, but can survive in nervous tissue for several days post infection. Neuroinfections of specific bird hosts as well as accidental mammalian hosts can lead to neuromotor effects, for example, leg paralysis and thus this parasite serves as a model of parasite invasion of the CNS. Here, we show by histological and immunohistochemical investigation of CNS invasion of immunocompetent (BALB/c) and immunodeficient (SCID) mice by T. regenti schistosomula that the presence of parasites in the nervous tissue initiated an influx of immune cells, activation of microglia, astrocytes and development of inflammatory lesions. Schistosomula elimination in the tissue depended on the host immune status. In the absence of CD3+ T-cells in immunodeficient SCID mice, parasite destruction was slower than that in immunocompetent BALB/c mice. Axon injury and subsequent secondary demyelination in the CNS were associated with mechanical damage due to migration of schistosomula through the nervous tissue, and not by host immune processes. Immunoreactivity of the parasite intestinal content for specific antigens of oligodendrocytes/myelin and neurofilaments showed for the first time that schistosomula ingest the nervous tissue components during their migration.
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Nawaratna SSK, McManus DP, Moertel L, Gobert GN, Jones MK. Gene Atlasing of digestive and reproductive tissues in Schistosoma mansoni. PLoS Negl Trop Dis 2011; 5:e1043. [PMID: 21541360 PMCID: PMC3082511 DOI: 10.1371/journal.pntd.0001043] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 03/25/2011] [Indexed: 11/30/2022] Open
Abstract
Background While considerable genomic and transcriptomic data are available for
Schistosoma mansoni, many of its genes lack significant
annotation. A transcriptomic study of individual tissues and organs of
schistosomes could play an important role in functional annotation of the
unknown genes, particularly by providing rapid localisation data and thus
giving insight into the potential roles of these molecules in parasite
development, reproduction and homeostasis, and in the complex host-parasite
interaction. Methodology/Principal Findings Quantification of gene expression in tissues of S. mansoni
was achieved by a combination of laser microdissection microscopy (LMM) and
oligonucleotide microarray analysis. We compared the gene expression profile
of the adult female gastrodermis and male and female reproductive tissues
with whole worm controls. The results revealed a total of 393 genes
(contigs) that were up-regulated two-fold or more in the gastrodermis, 4,450
in the ovary, 384 in the vitelline tissues of female parasites, and 2,171 in
the testes. We have also supplemented these data with the identification of
highly expressed genes in different regions of manually dissected male and
female S. mansoni. Though relatively crude, this dissection
strategy provides low resolution localisation data for critical regions of
the adult parasites that are not amenable to LMM isolation. Conclusions This is the first detailed transcriptomic study of the reproductive tissues
and gastrodermis of S. mansoni. The results obtained will
help direct future research on the functional aspects of these tissues,
expediting the characterisation of currently unannotated gene products of
S. mansoni and the discovery of new drug and vaccine
targets. There is currently only one drug available for treatment of
schistosomiasis mansoni and no vaccine. The searches for
possible new drug and vaccine candidates remain two major areas of current
research in schistosomiasis. There are considerable amounts of data available on
the genomics, transcriptomics and proteomics of Schistosoma
mansoni from which useful candidates for future drug and vaccine
development can be identified. Arranging these data into a biologically relevant
context through the characterisation of gene expression profiles of the
different tissues of this complex metazoan parasite, is an essential step in
identifying molecules with potential therapeutic value. We have used laser
microdissection microscopy and microarray analysis to show that many
tissue-specific genes are up-regulated in the digestive and reproductive tissues
of S. mansoni. This new knowledge provides an avenue to
investigate the molecular components associated with fundamental aspects of
schistosome biology.
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Meziane M, Brash EJ, Gilman R, Jones MK, Luo W, Pentchev L, Perdrisat CF, Puckett AJR, Punjabi V, Wesselmann FR, Ahmidouch A, Albayrak I, Aniol KA, Arrington J, Asaturyan A, Ates O, Baghdasaryan H, Benmokhtar F, Bertozzi W, Bimbot L, Bosted P, Boeglin W, Butuceanu C, Carter P, Chernenko S, Christy E, Commisso M, Cornejo JC, Covrig S, Danagoulian S, Daniel A, Davidenko A, Day D, Dhamija S, Dutta D, Ent R, Frullani S, Fenker H, Frlez E, Garibaldi F, Gaskell D, Gilad S, Goncharenko Y, Hafidi K, Hamilton D, Higinbotham DW, Hinton W, Horn T, Hu B, Huang J, Huber GM, Jensen E, Kang H, Keppel C, Khandaker M, King P, Kirillov D, Kohl M, Kravtsov V, Kumbartzki G, Li Y, Mamyan V, Margaziotis DJ, Markowitz P, Marsh A, Matulenko Y, Maxwell J, Mbianda G, Meekins D, Melnik Y, Miller J, Mkrtchyan A, Mkrtchyan H, Moffit B, Moreno O, Mulholland J, Narayan A, Nedev S, Piasetzky E, Pierce W, Piskunov NM, Prok Y, Ransome RD, Razin DS, Reimer PE, Reinhold J, Rondon O, Shabestari M, Shahinyan A, Shestermanov K, Širca S, Sitnik I, Smykov L, Smith G, Solovyev L, Solvignon P, Subedi R, Suleiman R, Tomasi-Gustafsson E, Vasiliev A, Vanderhaeghen M, Veilleux M, Wojtsekhowski BB, Wood S, Ye Z, Zanevsky Y, Zhang X, Zhang Y, Zheng X, Zhu L. Search for effects beyond the born approximation in polarization transfer observables in e(over→)p elastic scattering. PHYSICAL REVIEW LETTERS 2011; 106:132501. [PMID: 21520982 DOI: 10.1103/physrevlett.106.132501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Indexed: 05/30/2023]
Abstract
Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, G(E)/G(M), obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic H(e[over →],e(')p[over →]) reaction for three different beam energies at a Q(2)=2.5 GeV(2), spanning a wide range of the kinematic parameter ε. The ratio R, which equals μ(p)G(E)/G(M) in the Born approximation, is found to be independent of ε at the 1.5% level. The ε dependence of the longitudinal polarization transfer component P(ℓ) shows an enhancement of (2.3±0.6)% relative to the Born approximation at large ε.
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Hofmann A, Osman A, Leow CY, Driguez P, McManus DP, Jones MK. Parasite annexins--new molecules with potential for drug and vaccine development. Bioessays 2011; 32:967-76. [PMID: 21105292 DOI: 10.1002/bies.200900195] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In the last few years, annexins have been discovered in several nematodes and other parasites, and distinct differences between the parasite annexins and those of the hosts make them potentially attractive targets for anti-parasite therapeutics. Annexins are ubiquitous proteins found in almost all organisms across all kingdoms.Here, we present an overview of novel annexins from parasitic organisms, and summarize their phylogenetic and biochemical properties, with a view to using them as drug or vaccine targets. Building on structural and biological information that has been accumulated for mammalian and plant annexins, we describe a predicted additional secondary structure element found in many parasite annexins that may confer unique functional properties, and present a specific antigenic epitope for use as a vaccine.
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Schroder WA, Gardner J, Le TT, Duke M, Burke ML, Jones MK, McManus DP, Suhrbier A. SerpinB2 deficiency modulates Th1⁄Th2 responses after schistosome infection. Parasite Immunol 2011; 32:764-8. [PMID: 21086717 DOI: 10.1111/j.1365-3024.2010.01241.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
SerpinB2, also known as plasminogen activator inhibitor type-2, is a major product of macrophages and is upregulated during many infections. Although SerpinB2 inhibits urokinase plasminogen activator in vitro, evidence that this represents its physiological role in vivo is not compelling. We have recently shown that SerpinB2-/-mice generate enhanced Th1 responses after immunization with a Th1 immunogen. Herein,we show that Schistosoma japonicum granulomas induced liver SerpinB2 mRNA expression by >600-fold in wild-type mice. In SerpinB2-/- mice, worm and egg burden, and granuloma number and volume were unaffected. However, granulomas in these mice were associated with reduced fibrosis (as determined by Sirius red staining and image analysis) and increased iNOS, IL-6, IL-10 and TNFa and decreased Arg 1 and IL-13 mRNA expression. SerpinB2-/- mice immunized with soluble egg antigen (SEA) also showed reduced levels of SEA-specific IgG1. SerpinB2 deficiency thus promoted certain Th1 and reduced certain Th2 responses in response to this Th2 immunogen.
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Malace SP, Paolone M, Strauch S, Albayrak I, Arrington J, Berman BL, Brash EJ, Briscoe B, Camsonne A, Chen JP, Christy ME, Chudakov E, Cisbani E, Craver B, Cusanno F, Ent R, Garibaldi F, Gilman R, Glamazdin O, Glister J, Higinbotham DW, Hyde-Wright CE, Ilieva Y, de Jager CW, Jiang X, Jones MK, Keppel CE, Khrosinkova E, Kuchina E, Kumbartzki G, Lee B, Lindgren R, Margaziotis DJ, Meekins D, Michaels R, Park K, Pentchev L, Perdrisat CF, Piasetzky E, Punjabi VA, Puckett AJR, Qian X, Qiang Y, Ransome RD, Saha A, Sarty AJ, Schulte E, Solvignon P, Subedi RR, Tang L, Tedeschi D, Tvaskis V, Udias JM, Ulmer PE, Vignote JR, Wesselmann FR, Wojtsekhowski B, Zhan X. Precise extraction of the induced polarization in the 4He(e,e'p)3H reaction. PHYSICAL REVIEW LETTERS 2011; 106:052501. [PMID: 21405386 DOI: 10.1103/physrevlett.106.052501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 05/30/2023]
Abstract
We measured with unprecedented precision the induced polarization P(y) in (4)He(e,e'p)(3)H at Q(2)=0.8 and 1.3 (GeV/c)(2). The induced polarization is indicative of reaction-mechanism effects beyond the impulse approximation. Our results are in agreement with a relativistic distorted-wave impulse approximation calculation but are overestimated by a calculation with strong charge-exchange effects. Our data are used to constrain the strength of the spin-independent charge-exchange term in the latter calculation.
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You H, Gobert GN, Jones MK, Zhang W, McManus DP. Signalling pathways and the host-parasite relationship: putative targets for control interventions against schistosomiasis: signalling pathways and future anti-schistosome therapies. Bioessays 2011; 33:203-14. [PMID: 21290396 DOI: 10.1002/bies.201000077] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A better understanding of how schistosomes exploit host nutrients, neuro-endocrine hormones and signalling pathways for growth, development and maturation may provide new insights for improved interventions in the control of schistosomiasis. This paper describes recent advances in the identification and characterisation of schistosome tyrosine kinase and signalling pathways. It discusses the potential intervention value of insulin signalling, which may play an important role in glucose uptake and carbohydrate metabolism in schistosomes, providing the nutrients essential for parasite growth, development and, notably, female fecundity. Significant progress has also been made in the characterisation of other schistosome growth factor receptors, such as transforming growth factor beta receptor and epidermal growth factor receptor, and in our understanding of their roles in the host-parasite molecular dialogue and parasite development. The use of parasite signal transduction components as novel vaccine or drug targets may prove invaluable in prevention, treatment and control strategies to combat schistosomiasis.
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108
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Schulte L, Glanfield A, Nawaratna S, Gobert GN, McManus DP, Jones MK. Molecular analysis of zinc transporters in Schistosoma japonicum. Exp Parasitol 2011; 127:768-76. [PMID: 21255570 DOI: 10.1016/j.exppara.2011.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2010] [Revised: 11/19/2010] [Accepted: 01/11/2011] [Indexed: 11/30/2022]
Abstract
Members of the zinc-regulated transporter/iron-regulated transporter-like protein (ZIP) family of proteins transport metal ions across cell membranes. Genes encoding ZIPs are present in the genomes of schistosomes. Here, we describe molecular characterisation of six ZIPs (SjZIPA-F) from Schistosoma japonicum. Quantitative PCR analyses of these ZIPs through the lifecycle showed that each is expressed predominantly during the intramammalian stage and are particularly enriched in adult females. Using laser microdissected tissue as template, SjZIPA-D were transcriptionally enriched in female reproductive tissues, SjZIPE was not expressed in specific tissues and SjZIPF was expressed similarly in each tissue. Whole mount in situ hybridization revealed that SjZIPA and SjZIPB were localised to the oesophageal gland of adults and the vitellaria. We have shown that multiple ZIPs are expressed by schistosomes during the intramammalian parasitic phases and propose that the encoded products perform diverse cellular functions related to metal transport in different cells of S. japonicum.
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Riordan S, Abrahamyan S, Craver B, Kelleher A, Kolarkar A, Miller J, Cates GD, Liyanage N, Wojtsekhowski B, Acha A, Allada K, Anderson B, Aniol KA, Annand JRM, Arrington J, Averett T, Beck A, Bellis M, Boeglin W, Breuer H, Calarco JR, Camsonne A, Chen JP, Chudakov E, Coman L, Crowe B, Cusanno F, Day D, Degtyarenko P, Dolph PAM, Dutta C, Ferdi C, Fernández-Ramírez C, Feuerbach R, Fraile LM, Franklin G, Frullani S, Fuchs S, Garibaldi F, Gevorgyan N, Gilman R, Glamazdin A, Gomez J, Grimm K, Hansen JO, Herraiz JL, Higinbotham DW, Holmes R, Holmstrom T, Howell D, de Jager CW, Jiang X, Jones MK, Katich J, Kaufman LJ, Khandaker M, Kelly JJ, Kiselev D, Korsch W, LeRose J, Lindgren R, Markowitz P, Margaziotis DJ, Beck SMT, Mayilyan S, McCormick K, Meziani ZE, Michaels R, Moffit B, Nanda S, Nelyubin V, Ngo T, Nikolenko DM, Norum B, Pentchev L, Perdrisat CF, Piasetzky E, Pomatsalyuk R, Protopopescu D, Puckett AJR, Punjabi VA, Qian X, Qiang Y, Quinn B, Rachek I, Ransome RD, Reimer PE, Reitz B, Roche J, Ron G, Rondon O, Rosner G, Saha A, Sargsian MM, Sawatzky B, Segal J, Shabestari M, Shahinyan A, Shestakov Y, Singh J, Sirca S, Souder P, Stepanyan S, Stibunov V, Sulkosky V, Tajima S, Tobias WA, Udias JM, Urciuoli GM, Vlahovic B, Voskanyan H, Wang K, Wesselmann FR, Vignote JR, Wood SA, Wright J, Yao H, Zhu X. Measurements of the electric form factor of the neutron up to Q2=3.4 GeV2 using the reaction 3He(e,e'n)pp. PHYSICAL REVIEW LETTERS 2010; 105:262302. [PMID: 21231649 DOI: 10.1103/physrevlett.105.262302] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Indexed: 02/05/2023]
Abstract
The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively.
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110
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Fomin N, Arrington J, Day DB, Gaskell D, Daniel A, Seely J, Asaturyan R, Benmokhtar F, Boeglin W, Boillat B, Bosted P, Bruell A, Bukhari MHS, Christy ME, Chudakov E, Clasie B, Connell SH, Dalton MM, Dutta D, Ent R, El Fassi L, Fenker H, Filippone BW, Garrow K, Hill C, Holt RJ, Horn T, Jones MK, Jourdan J, Kalantarians N, Keppel CE, Kiselev D, Kotulla M, Lindgren R, Lung AF, Malace S, Markowitz P, McKee P, Meekins DG, Miyoshi T, Mkrtchyan H, Navasardyan T, Niculescu G, Okayasu Y, Opper AK, Perdrisat C, Potterveld DH, Punjabi V, Qian X, Reimer PE, Roche J, Rodriguez VM, Rondon O, Schulte E, Segbefia E, Slifer K, Smith GR, Solvignon P, Tadevosyan V, Tajima S, Tang L, Testa G, Trojer R, Tvaskis V, Vulcan WF, Wasko C, Wesselmann FR, Wood SA, Wright J, Zheng X. Scaling of the F2 structure function in nuclei and quark distributions at x>1. PHYSICAL REVIEW LETTERS 2010; 105:212502. [PMID: 21231294 DOI: 10.1103/physrevlett.105.212502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 05/30/2023]
Abstract
We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.
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Toh SQ, Glanfield A, Gobert GN, Jones MK. Heme and blood-feeding parasites: friends or foes? Parasit Vectors 2010; 3:108. [PMID: 21087517 PMCID: PMC2999593 DOI: 10.1186/1756-3305-3-108] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 11/18/2010] [Indexed: 12/01/2022] Open
Abstract
Hemoparasites, like malaria and schistosomes, are constantly faced with the challenges of storing and detoxifying large quantities of heme, released from their catabolism of host erythrocytes. Heme is an essential prosthetic group that forms the reactive core of numerous hemoproteins with diverse biological functions. However, due to its reactive nature, it is also a potentially toxic molecule. Thus, the acquisition and detoxification of heme is likely to be paramount for the survival and establishment of parasitism. Understanding the underlying mechanism involved in this interaction could possibly provide potential novel targets for drug and vaccine development, and disease treatment. However, there remains a wide gap in our understanding of these mechanisms. This review summarizes the biological importance of heme for hemoparasite, and the adaptations utilized in its sequestration and detoxification.
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Glanfield A, McManus DP, Smyth DJ, Lovas EM, Loukas A, Gobert GN, Jones MK. A cytochrome b561 with ferric reductase activity from the parasitic blood fluke, Schistosoma japonicum. PLoS Negl Trop Dis 2010; 4:e884. [PMID: 21103361 PMCID: PMC2982821 DOI: 10.1371/journal.pntd.0000884] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 10/18/2010] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Iron has an integral role in numerous cellular reactions and is required by virtually all organisms. In physiological conditions, iron is abundant in a largely insoluble ferric state. Ferric reductases are an essential component of iron uptake by cells, reducing iron to the soluble ferrous form. Cytochromes b561 (cyts-b561) are a family of ascorbate reducing transmembrane proteins found in most eukaryotic cells. The identification of the ferric reductase duodenal cytochrome b (dcytb) and recent observations that other cyts-b561 may be involved in iron metabolism have opened novel perspectives for elucidating their physiological function. METHODOLOGY/PRINCIPAL FINDINGS Here we have identified a new member of the cytochrome b561 (Sjcytb561) family in the pathogenic blood fluke Schistosoma japonicum that localises to the outer surface of this parasitic trematode. Heterologous expression of recombinant Sjcyt-b561 in a Saccharomyces cerevisiae mutant strain that lacks plasma membrane ferrireductase activity demonstrated that the molecule could rescue ferric reductase activity in the yeast. SIGNIFICANCE/CONCLUSIONS This finding of a new member of the cytochrome b561 family further supports the notion that a ferric reductase function is likely for other members of this protein family. Additionally, the localisation of Sjcytb561 in the surface epithelium of these blood-dwelling schistosomes contributes further to our knowledge concerning nutrient acquisition in these parasites and may provide novel targets for therapeutic intervention.
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Slifer K, Rondón OA, Aghalaryan A, Ahmidouch A, Asaturyan R, Bloch F, Boeglin W, Bosted P, Carasco C, Carlini R, Cha J, Chen JP, Christy ME, Cole L, Coman L, Crabb D, Danagoulian S, Day D, Dunne J, Elaasar M, Ent R, Fenker H, Frlez E, Gaskell D, Gan L, Gomez J, Hu B, Jourdan J, Jones MK, Keith C, Keppel CE, Khandaker M, Klein A, Kramer L, Liang Y, Lichtenstadt J, Lindgren R, Mack D, McKee P, McNulty D, Meekins D, Mkrtchyan H, Nasseripour R, Niculescu I, Normand K, Norum B, Pocanic D, Prok Y, Raue B, Reinhold J, Roche J, Kiselev D, Savvinov N, Sawatzky B, Seely M, Sick I, Smith C, Smith G, Stepanyan S, Tang L, Tajima S, Testa G, Vulcan W, Wang K, Warren G, Wesselmann FR, Wood S, Yan C, Yuan L, Yun J, Zeier M, Zhu H. Probing quark-gluon interactions with transverse polarized scattering. PHYSICAL REVIEW LETTERS 2010; 105:101601. [PMID: 20867509 DOI: 10.1103/physrevlett.105.101601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2009] [Revised: 08/24/2010] [Indexed: 05/29/2023]
Abstract
We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.
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Paolone M, Malace SP, Strauch S, Albayrak I, Arrington J, Berman BL, Brash EJ, Briscoe B, Camsonne A, Chen JP, Christy ME, Chudakov E, Cisbani E, Craver B, Cusanno F, Ent R, Garibaldi F, Gilman R, Glamazdin O, Glister J, Higinbotham DW, Hyde-Wright CE, Ilieva Y, de Jager CW, Jiang X, Jones MK, Keppel CE, Khrosinkova E, Kuchina E, Kumbartzki G, Lee B, Lindgren R, Margaziotis DJ, Meekins D, Michaels R, Park K, Pentchev L, Perdrisat CF, Piasetzky E, Punjabi VA, Puckett AJR, Qian X, Qiang Y, Ransome RD, Saha A, Sarty AJ, Schulte E, Solvignon P, Subedi RR, Tang L, Tedeschi D, Tvaskis V, Udias JM, Ulmer PE, Vignote JR, Wesselmann FR, Wojtsekhowski B, Zhan X. Polarization transfer in the 4He(e,e'p)3H reaction at Q2=0.8 and 1.3 (GeV/c)2. PHYSICAL REVIEW LETTERS 2010; 105:072001. [PMID: 20868031 DOI: 10.1103/physrevlett.105.072001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Indexed: 05/29/2023]
Abstract
Proton recoil polarization was measured in the quasielastic 4He(e,e'p)3H reaction at Q{2}=0.8 and 1.3 (GeV/c){2} with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e,e'p) reaction, contradicting a relativistic distorted-wave approximation and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton.
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Zhang W, Li J, Jones MK, Zhang Z, Zhao L, Blair D, McManus DP. The Echinococcus granulosus antigen B gene family comprises at least 10 unique genes in five subclasses which are differentially expressed. PLoS Negl Trop Dis 2010; 4:e784. [PMID: 20706625 PMCID: PMC2919375 DOI: 10.1371/journal.pntd.0000784] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 07/07/2010] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Antigen B (EgAgB) is a major protein produced by the metacestode cyst of Echinococcus granulosus, the causative agent of cystic hydatid disease. This protein has been shown to play an important role in modulating host immune responses, although its precise biological function still remains unknown. It is generally accepted that EgAgB is comprised of a gene family of five subfamilies which are highly polymorphic, but the actual number of genes present is unknown. METHODOLOGY/PRINCIPAL FINDINGS Based on published sequences for the family, we designed specific primers for each subfamily and used PCR to amplify them from genomic DNA isolated from individual mature adult worms (MAW) taken from an experimentally infected dog in China and individual larval protoscoleces (PSC) excised from a single hydatid cyst taken from an Australian kangaroo. We then used real-time PCR to measure expression of each of the genes comprising the five EgAgB subfamilies in all life-cycle stages including the oncosphere (ONC). CONCLUSIONS/SIGNIFICANCE Based on sequence alignment analysis, we found that the EgAgB gene family comprises at least ten unique genes. Each of the genes was identical in both larval and adult E. granulosus isolates collected from two geographical areas (different continents). DNA alignment comparisons with EgAgB sequences deposited in GenBank databases showed that each gene in the gene family is highly conserved within E. granulosus, which contradicts previous studies claiming significant variation and polymorphism in EgAgB. Quantitative PCR analysis revealed that the genes were differentially expressed in different life-cycle stages of E. granulosus with EgAgB3 expressed predominantly in all stages. These findings are fundamental for determining the expression and the biological function of antigen B.
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Puckett AJR, Brash EJ, Jones MK, Luo W, Meziane M, Pentchev L, Perdrisat CF, Punjabi V, Wesselmann FR, Ahmidouch A, Albayrak I, Aniol KA, Arrington J, Asaturyan A, Baghdasaryan H, Benmokhtar F, Bertozzi W, Bimbot L, Bosted P, Boeglin W, Butuceanu C, Carter P, Chernenko S, Christy E, Commisso M, Cornejo JC, Covrig S, Danagoulian S, Daniel A, Davidenko A, Day D, Dhamija S, Dutta D, Ent R, Frullani S, Fenker H, Frlez E, Garibaldi F, Gaskell D, Gilad S, Gilman R, Goncharenko Y, Hafidi K, Hamilton D, Higinbotham DW, Hinton W, Horn T, Hu B, Huang J, Huber GM, Jensen E, Keppel C, Khandaker M, King P, Kirillov D, Kohl M, Kravtsov V, Kumbartzki G, Li Y, Mamyan V, Margaziotis DJ, Marsh A, Matulenko Y, Maxwell J, Mbianda G, Meekins D, Melnik Y, Miller J, Mkrtchyan A, Mkrtchyan H, Moffit B, Moreno O, Mulholland J, Narayan A, Nedev S, Piasetzky E, Pierce W, Piskunov NM, Prok Y, Ransome RD, Razin DS, Reimer P, Reinhold J, Rondon O, Shabestari M, Shahinyan A, Shestermanov K, Sirca S, Sitnik I, Smykov L, Smith G, Solovyev L, Solvignon P, Subedi R, Tomasi-Gustafsson E, Vasiliev A, Veilleux M, Wojtsekhowski BB, Wood S, Ye Z, Zanevsky Y, Zhang X, Zhang Y, Zheng X, Zhu L. Recoil polarization measurements of the proton electromagnetic form factor ratio to Q2 = 8.5 GeV2. PHYSICAL REVIEW LETTERS 2010; 104:242301. [PMID: 20873943 DOI: 10.1103/physrevlett.104.242301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Indexed: 05/29/2023]
Abstract
Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this Letter, we report new measurements of the proton electromagnetic form factor ratio using the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5 GeV2. By extending the range of Q2 for which G(E)(p) is accurately determined by more than 50%, these measurements will provide significant constraints on models of nucleon structure in the nonperturbative regime.
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Jones MK, Padilla OR, Zhu E. Survivin is a key factor in the differential susceptibility of gastric endothelial and epithelial cells to alcohol-induced injury. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2010; 61:253-264. [PMID: 20610854 PMCID: PMC2953945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 05/25/2010] [Indexed: 05/29/2023]
Abstract
We previously demonstrated that the anti-apoptosis protein, survivin, plays a protective role against alcohol-induced gastric injury. Since the endothelium is a primary target of alcohol-induced gastric damage, we investigated whether survivin expression is a key factor in the greater susceptibility of gastric endothelial vs. epithelial cells to alcohol-induced injury. Here, we demonstrate that rat gastric epithelial cells (RGM1 cells, an epithelial cell line derived from normal rat gastric mucosa) expressed 7.5-fold greater survivin protein levels vs. rat gastric endothelial cells. Survivin expression correlated with resistance of gastric epithelial vs. endothelial cells to both alcohol-induced cell damage and alcohol-induced apoptosis. Suppression of survivin protein expression levels using siRNA rendered the gastric epithelial cells as susceptible to both alcohol-induced cell damage and apoptosis as the gastric endothelial cells. Conversely, forced overexpression of survivin by transient transfection rendered gastric endothelial cells as resistant to both alcohol-induced cell damage and apoptosis as mock-transfected gastric epithelial cells. Moreover, overexpression of a threonine-34 to glutamate phosphorylation mimic mutant survivin construct rendered gastric endothelial cells significantly more resistant to alcohol-induced damage and apoptosis vs. mock-transfected gastric epithelial cells. These findings indicate that disparate survivin expression levels can explain the discrepancy between gastric epithelial and endothelial cell susceptibility to alcohol-induced injury; and, that a negative charge at amino acid residue 34 on survivin, such as that which naturally occurs by phosphorylation of threonine-34, enhances its property in conferring gastric mucosal protection.
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Burke ML, McManus DP, Ramm GA, Duke M, Li Y, Jones MK, Gobert GN. Co-ordinated gene expression in the liver and spleen during Schistosoma japonicum infection regulates cell migration. PLoS Negl Trop Dis 2010; 4:e686. [PMID: 20502518 PMCID: PMC2872641 DOI: 10.1371/journal.pntd.0000686] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 03/26/2010] [Indexed: 12/15/2022] Open
Abstract
Determining the molecular events induced in the spleen during schistosome infection is an essential step in better understanding the immunopathogenesis of schistosomiasis and the mechanisms by which schistosomes modulate the host immune response. The present study defines the transcriptional and cellular events occurring in the murine spleen during the progression of Schistosoma japonicum infection. Additionally, we compared and contrasted these results with those we have previously reported for the liver. Microarray analysis combined with flow cytometry and histochemistry demonstrated that transcriptional changes occurring in the spleen were closely related to changes in cellular composition. Additionally, the presence of alternatively activated macrophages, as indicated by up-regulation of Chi3l3 and Chi3l4 and expansion of F4/80+ macrophages, together with enhanced expression of the immunoregulatory genes ANXA1 and CAMP suggests the spleen may be an important site for the control of S. japonicum-induced immune responses. The most striking difference between the transcriptional profiles of the infected liver and spleen was the contrasting expression of chemokines and cell adhesion molecules. Lymphocyte chemokines, including the homeostatic chemokines CXCL13, CCL19 and CCL21, were significantly down-regulated in the spleen but up-regulated in the liver. Eosinophil (CCL11, CCL24), neutrophil (CXCL1) and monocyte (CXCL14, CCL12) chemokines and the cell adhesion molecules VCAM1, NCAM1, PECAM1 were up-regulated in the liver but unchanged in the spleen. Chemokines up-regulated in both organs were expressed at significantly higher levels in the liver. Co-ordinated expression of these genes probably contributes to the development of a chemotactic signalling gradient that promotes recruitment of effector cells to the liver, thereby facilitating the development of hepatic granulomas and fibrosis. Together these data provide, for the first time, a comprehensive overview of the molecular events occurring in the spleen during schistosomiasis and will substantially further our understanding of the local and systemic mechanisms driving the immunopathogenesis of this disease. Schistosomiasis is a significant cause of illness and death in the developing world. Inflammation and scarring in the liver and enlargement of the spleen (splenomegaly) are common features of the disease. Changes occurring in the spleen have the potential to influence the way in which the body deals with infection but the mechanisms driving these changes are not well characterised. In the present study we determined, for the first time, the gene expression profile of the mouse spleen during infection with Schistosoma japonicum and compared these results to those previously reported for the liver to determine if processes occurring in these organs co-operate to promote hepatic inflammation and granuloma formation. Our data indicated that gene expression in the spleen is related to the types of cells present and suggest that the spleen might be important in controlling schistosome-induced inflammation. Comparison of the liver and spleen showed that expression of cell signalling molecules (chemokines) was much higher in the liver, potentially promoting the recruitment of specific cell types to this organ, causing inflammation and scarring. The results from this study enhance our knowledge of the mechanisms that drive schistosome-induced splenomegaly and liver inflammation.
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Jabbar A, Crawford S, Młocicki D, Swiderski ZP, Conn DB, Jones MK, Beveridge I, Lightowlers MW. Ultrastructural reconstruction of Taenia ovis oncospheres from serial sections. Int J Parasitol 2010; 40:1419-31. [PMID: 20478311 DOI: 10.1016/j.ijpara.2010.04.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 04/22/2010] [Accepted: 04/26/2010] [Indexed: 11/17/2022]
Abstract
The cellular organisation of Taenia ovis oncospheres is interpreted from ultrathin serial sections and transmission electron microscopy following high pressure freezing and freeze-substitution. The surface of a hatched, non-activated T. ovis oncosphere is covered by an oncospheral membrane below which is the tegument bearing microvilli. The basal lamina of the tegument is underlain by broad bands of peripheral somatic musculature. Three pairs of hooks and associated muscles are present in the somatophoric third of the oncosphere. Approximately 19 cells of seven different types were identified which include: (i) a quadri-nucleated syncytium of penetration gland type 1 containing two lateral pairs of cell bodies interconnected by narrow cytoplasmic bridges (PG1); (ii) a quadri-nucleated syncytium of penetration gland type 2 (PG2); (iii) a single-nucleated median mesophoric gland cell; (iv) 10 somatic cells; (v) two germinative cells; (vi) two nerve cells; and (vii) a pair of median somatophoric cells. This study provides a clear understanding of the morphology of T. ovis oncospheres and forms the basis for further investigations into the biology of taeniid oncospheres.
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Tran MH, Freitas TC, Cooper L, Gaze S, Gatton ML, Jones MK, Lovas E, Pearce EJ, Loukas A. Suppression of mRNAs encoding tegument tetraspanins from Schistosoma mansoni results in impaired tegument turnover. PLoS Pathog 2010; 6:e1000840. [PMID: 20419145 PMCID: PMC2855321 DOI: 10.1371/journal.ppat.1000840] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 03/03/2010] [Indexed: 12/22/2022] Open
Abstract
Schistosomes express a family of integral membrane proteins, called tetraspanins (TSPs), in the outer surface membranes of the tegument. Two of these tetraspanins, Sm-TSP-1 and Sm-TSP-2, confer protection as vaccines in mice, and individuals who are naturally resistant to S. mansoni infection mount a strong IgG response to Sm-TSP-2. To determine their functions in the tegument of S. mansoni we used RNA interference to silence expression of Sm-tsp-1 and Sm-tsp-2 mRNAs. Soaking of parasites in Sm-tsp dsRNAs resulted in 61% (p = 0.009) and 74% (p = 0.009) reductions in Sm-tsp-1 and Sm-tsp-2 transcription levels, respectively, in adult worms, and 67%–75% (p = 0.011) and 69%–89% (p = 0.004) reductions in Sm-tsp-1 and Sm-tsp-2 transcription levels, respectively, in schistosomula compared to worms treated with irrelevant control (luciferase) dsRNA. Ultrastructural morphology of adult worms treated in vitro with Sm-tsp-2 dsRNA displayed a distinctly vacuolated and thinner tegument compared with controls. Schistosomula exposed in vitro to Sm-tsp-2 dsRNA had a significantly thinner and more vacuolated tegument, and morphology consistent with a failure of tegumentary invaginations to close. Injection of mice with schistosomula that had been electroporated with Sm-tsp-1 and Sm-tsp-2 dsRNAs resulted in 61% (p = 0.005) and 83% (p = 0.002) reductions in the numbers of parasites recovered from the mesenteries four weeks later when compared to dsRNA-treated controls. These results imply that tetraspanins play important structural roles impacting tegument development, maturation or stability. Schistosomes, or blood flukes, reside in the blood vessels surrounding the liver and bowel of their human hosts. They infect 200 million people and kill many thousands each year in developing countries. The parasites cover themselves in a unique series of cell membranes called the tegument. Molecules in the tegument membranes are a major target for the development of new drugs and vaccines against the parasite. Here we show that at least one member of a family of tegument membrane proteins called tetraspanins, Sm-TSP-2, is integral to the proper formation of the tegument and subsequent survival of the parasite in its human host, providing a potential mechanism by which a vaccine based on Sm-TSP-2 protects immunized hosts.
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Ahluwalia A, Narula J, Jones MK, Deng X, Tarnawski AS. Impaired angiogenesis in aging myocardial microvascular endothelial cells is associated with reduced importin alpha and decreased nuclear transport of HIF1 alpha: mechanistic implications. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY : AN OFFICIAL JOURNAL OF THE POLISH PHYSIOLOGICAL SOCIETY 2010; 61:133-9. [PMID: 20436213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Accepted: 03/19/2010] [Indexed: 02/06/2023]
Abstract
Aging is associated with increased incidence of myocardial infarctions and impaired angiogenesis - new capillary blood vessel formation from preexisting vessels. The molecular mechanism(s) of aging-related impairment of angiogenesis are unknown. In the present study we focused on the mechanism of activation of the gene for vascular endothelial growth factor (VEGF - the most potent stimulator of angiogenesis) in young and aging myocardial microvascular endothelial cells (MMEC). Activation of VEGF gene in the cell nucleus is mediated in part by the transcription factor hypoxia-inducible factor 1 alpha (HIF1 alpha). In order to activate VEGF gene, HIF1 alpha must first be transported to the nucleus, but the mechanisms of this transport are unknown. We hypothesized that reduced VEGF gene activation and impaired angiogenesis in myocardium during aging can result from downregulation of the nuclear transport receptor - importin alpha that leads to decreased transport of HIF1 alpha to the nucleus. We examined in MMEC isolated from young (3 months of age) and aging (24 months old) Fisher F-344 rats: 1) in vitro angiogenesis; and 2) the expression of VEGF, importin alpha and HIF1 alpha. Aging MMEC exhibited a 3.7-fold reduction in angiogenesis and a corresponding reduction in VEGF (by 3-fold) and importin alpha (by 1.9-fold) levels compared to young MMEC. Aging MMEC also exhibited cytoplasmic accumulation (by 1.8-fold) of HIF1 alpha protein, reduced HIF1 alpha transport to the nucleus and decreased binding of HIF1 alpha protein to the VEGF gene promoter. This study is the first demonstration of the downregulation of importin alpha in aging MMEC and reduced nuclear transport of HIF1 alpha, which likely lead to decreased VEGF gene activation and impaired angiogenesis.
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You H, Zhang W, Jones MK, Gobert GN, Mulvenna J, Rees G, Spanevello M, Blair D, Duke M, Brehm K, McManus DP. Cloning and characterisation of Schistosoma japonicum insulin receptors. PLoS One 2010; 5:e9868. [PMID: 20352052 PMCID: PMC2844434 DOI: 10.1371/journal.pone.0009868] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2010] [Accepted: 03/02/2010] [Indexed: 11/30/2022] Open
Abstract
Background Schistosomes depend for growth and development on host hormonal signals, which may include the insulin signalling pathway. We cloned and assessed the function of two insulin receptors from Schistosoma japonicum in order to shed light on their role in schistosome biology. Methodology/Principal Findings We isolated, from S. japonicum, insulin receptors 1 (SjIR-1) and 2 (SjIR-2) sharing close sequence identity to their S. mansoni homologues (SmIR-1 and SmIR-2). SjIR-1 is located on the tegument basal membrane and the internal epithelium of adult worms, whereas SjIR-2 is located in the parenchyma of males and the vitelline tissue of females. Phylogenetic analysis showed that SjIR-2 and SmIR-2 are close to Echinococcus multilocularis insulin receptor (EmIR), suggesting that SjIR-2, SmIR-2 and EmIR share similar roles in growth and development in the three taxa. Structure homology modelling recovered the conserved structure between the SjIRs and Homo sapiens IR (HIR) implying a common predicted binding mechanism in the ligand domain and the same downstream signal transduction processing in the tyrosine kinase domain as in HIR. Two-hybrid analysis was used to confirm that the ligand domains of SjIR-1 and SjIR-2 contain the insulin binding site. Incubation of adult worms in vitro, both with a specific insulin receptor inhibitor and anti-SjIRs antibodies, resulted in a significant decrease in worm glucose levels, suggesting again the same function for SjIRs in regulating glucose uptake as described for mammalian cells. Conclusions Adult worms of S. japonicum possess insulin receptors that can specifically bind to insulin, indicating that the parasite can utilize host insulin for development and growth by sharing the same pathway as mammalian cells in regulating glucose uptake. A complete understanding of the role of SjIRs in the biology of S. japonicum may result in their use as new targets for drug and vaccine development against schistosomiasis.
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McDonald CJ, Jones MK, Wallace DF, Summerville L, Nawaratna S, Subramaniam VN. Increased iron stores correlate with worse disease outcomes in a mouse model of schistosomiasis infection. PLoS One 2010; 5:e9594. [PMID: 20231891 PMCID: PMC2834747 DOI: 10.1371/journal.pone.0009594] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Accepted: 02/15/2010] [Indexed: 11/19/2022] Open
Abstract
Schistosomiasis is a significant parasitic infection creating disease burden throughout many of the world's developing nations. Iron deficiency anemia is also a significant health burden resulting from both nutritional deficit as well as parasitic infection in these countries. In this study we investigated the relationships between the disease outcomes of Schistosoma japonicum infection and iron homeostasis. We aimed to determine if host iron status has an effect on schistosome maturation or egg production, and to investigate the response of iron regulatory genes to chronic schistosomiasis infection. Wild-type C57BL/6 and Transferrin Receptor 2 null mice were infected with S. japonicum, and sacrificed at the onset of chronic disease. Transferrin Receptor 2 null mice are a model of type 3 hereditary hemochromatosis and develop significant iron overload providing increased iron stores at the onset of infection. The infectivity of schistosomes and egg production was assessed along with the subsequent development of granulomas and fibrosis. The response of the iron regulatory gene Hepcidin to infection and the changes in iron status were assessed by real-time PCR and Western blotting. Our results show that Hepcidin levels responded to the changing iron status of the animals, but were not significantly influenced by the inflammatory response. We also show that with increased iron availability at the time of infection there was greater development of fibrosis around granulomas. In conclusion, our studies indicate that chronic inflammation may not be the primary cause of the anemia seen in schistosomiasis, and suggest that increased availability of iron, such as through iron supplementation, may actually lead to increased disease severity.
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Mulvenna J, Sripa B, Brindley PJ, Gorman J, Jones MK, Colgrave ML, Jones A, Nawaratna S, Laha T, Suttiprapa S, Smout MJ, Loukas A. The secreted and surface proteomes of the adult stage of the carcinogenic human liver fluke Opisthorchis viverrini. Proteomics 2010; 10:1063-78. [PMID: 20049860 PMCID: PMC3038172 DOI: 10.1002/pmic.200900393] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Accepted: 11/30/2009] [Indexed: 01/30/2023]
Abstract
Infection with the human liver fluke, Opisthorchis viverrini, is a serious public health problem in Thailand, Laos and nearby locations in Southeast Asia. Both experimental and epidemiological evidence strongly implicate liver fluke infection in the etiology of one of the liver cancer subtypes, cholangiocarcinoma (CCA). To identify parasite proteins critical for liver fluke survival and the etiology of CCA, OFFGEL electrophoresis and multiple reaction monitoring were employed to characterize 300 parasite proteins from the O. viverrini excretory/secretory products and, utilizing selective labeling and sequential solubilization, from the host-exposed tegument. The excretory/secretory included a complex mixture of proteins that have been associated with cancers, including proteases of different mechanistic classes and orthologues of mammalian growth factors and anti-apoptotic proteins. Also identified was a cysteine protease inhibitor which, in other helminth pathogens, induces nitric oxide production by macrophages, and, hence may contribute to malignant transformation of inflamed cells. More than 160 tegumental proteins were identified using sequential solubilization of isolated teguments, and a subset of these was localized to the surface membrane of the tegument by labeling living flukes with biotin and confirming surface localization with fluorescence microscopy. These included annexins, which are potential immuno-modulators, and orthologues of the schistosomiasis vaccine antigens Sm29 and tetraspanin-2. Novel roles in pathogenesis were suggested for the tegument-host interface since more than ten surface proteins had no homologues in the public databases. The O. viverrini proteins identified here provide an extensive catalogue of novel leads for research on the pathogenesis of opisthorchiasis and the development of novel interventions for this disease and CCA, as well as providing a scaffold for sequencing the genome of this fluke.
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Gobert GN, Tran MH, Moertel L, Mulvenna J, Jones MK, McManus DP, Loukas A. Transcriptional changes in Schistosoma mansoni during early schistosomula development and in the presence of erythrocytes. PLoS Negl Trop Dis 2010; 4:e600. [PMID: 20161728 PMCID: PMC2817720 DOI: 10.1371/journal.pntd.0000600] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 12/17/2009] [Indexed: 12/27/2022] Open
Abstract
Background Schistosomes cause more mortality and morbidity than any other human helminth, but control primarily relies on a single drug that kills adult worms. The newly transformed schistosomulum stage is susceptible to the immune response and is a target for vaccine development and rational drug design. Methodology/Principal Findings To identify genes which are up-regulated during the maturation of Schistosoma mansoni schistosomula in vitro, we cultured newly transformed parasites for 3 h or 5 days with and without erythrocytes and compared their transcriptional profiles using cDNA microarrays. The most apparent changes were in the up-regulation of genes between 3 h and 5 day schistosomula involved in blood feeding, tegument and cytoskeletal development, cell adhesion, and stress responses. The most highly up-regulated genes included a tegument tetraspanin Sm-tsp-3 (1,600-fold up-regulation), a protein kinase, a novel serine protease and serine protease inhibitor, and intestinal proteases belonging to distinct mechanistic classes. The inclusion of erythrocytes in the culture medium resulted in a general but less pronounced increase in transcriptional activity, with the highest up-regulation of genes involved in iron metabolism, proteolysis, and transport of fatty acids and sugars. Conclusions We have identified the genes that are up-regulated during the first 5 days of schistosomula development in vitro. Using a combination of gene silencing techniques and murine protection studies, some of these highly up-regulated transcripts can be targeted for future development of new vaccines and drugs. Schistosome blood flukes cause more mortality and morbidity than any other human worm infection, but current control methods primarily rely on a single drug. There is a desperate need for new approaches to control this parasite, including vaccines. People become infected when the free-swimming larva, the cercaria, enters through the skin and becomes the schistosomulum. Schistosomula are susceptible to immune responses during their first few days in the host before they become adult parasites. We characterised the genes that these newly transformed parasites switch on when they enter the host to identify molecules that are critical for survival in the human host. Some of these highly up-regulated genes can be targeted for future development of new vaccines and drugs.
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