12 results on '"Decrem Y"'
Search Results
2. Ixodes ticks belonging to the Ixodes ricinus complex encode a family of anticomplement proteins
- Author
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Daix, V., Schroeder, H., Praet, N., Georgin, J.-P., Chiappino, I., Gillet, L., de Fays, K., Decrem, Y., Leboulle, G., Godfroid, E., Bollen, A., Pastoret, P.-P., Gern, Lise, Sharp, P. M., Vanderplasschen, A., Daix, V., Schroeder, H., Praet, N., Georgin, J.-P., Chiappino, I., Gillet, L., de Fays, K., Decrem, Y., Leboulle, G., Godfroid, E., Bollen, A., Pastoret, P.-P., Gern, Lise, Sharp, P. M., and Vanderplasschen, A.
- Abstract
The alternative pathway of complement is an important innate defence against pathogens including ticks. This component of the immune system has selected for pathogens that have evolved countermeasures. Recently, a salivary protein able to inhibit the alternative pathway was cloned from the American tick Ixodes scapularis (Valenzuela et al., 2000; J. Biol. Chem. 275, 18717–18723). Here, we isolated two different sequences, similar to Isac, from the transcriptome of I. ricinus salivary glands. Expression of these sequences revealed that they both encode secreted proteins able to inhibit the complement alternative pathway. These proteins, called I. ricinus anticomplement (IRAC) protein I and II, are coexpressed constitutively in I. ricinus salivary glands and are upregulated during blood feeding. Also, we demonstrated that they are the products of different genes and not of alleles of the same locus. Finally, phylogenetic analyses demonstrate that ticks belonging to the Ixodes ricinus complex encode a family of relatively small anticomplement molecules undergoing diversification by positive Darwinian selection.
- Published
- 2009
3. Electrochemical DNA hybridization detection using peptide nucleic acids and [Ru(NH3)6]3+ on gold electrodes
- Author
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Steichen, M., primary, Decrem, Y., additional, Godfroid, E., additional, and Buess-Herman, C., additional
- Published
- 2007
- Full Text
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4. Ixodes ticks belonging to the Ixodes ricinus complex encode a family of anticomplement proteins
- Author
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Daix, V., primary, Schroeder, H., additional, Praet, N., additional, Georgin, J.-P., additional, Chiappino, I., additional, Gillet, L., additional, de Fays, K., additional, Decrem, Y., additional, Leboulle, G., additional, Godfroid, E., additional, Bollen, A., additional, Pastoret, P.-P., additional, Gern, L., additional, Sharp, P. M., additional, and Vanderplasschen, A., additional
- Published
- 2007
- Full Text
- View/download PDF
5. Electrochemical DNA hybridization detection using peptide nucleic acids and [Ru(NH3)6]3+ on gold electrodes
- Author
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Steichen, M., Decrem, Y., Godfroid, E., and Buess-Herman, C.
- Subjects
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BIOSENSORS , *DNA , *NUCLEIC acid hybridization , *ELECTRODES - Abstract
Abstract: An electrochemical DNA hybridization detection method based on the electrostatic interactions of [Ru(NH3)6]3+ cations with the anionic phosphate backbone of DNA is proposed. PNA molecules are immobilized as capture probes on the gold substrate. The cationic ruthenium complexes do not interact electrostatically with the PNA probes due to the absence of the anionic phosphate groups on the PNA probes. But after hybridization, [Ru(NH3)6]3+ is adsorbed on the DNA backbone, giving a clear hybridization detection signal in ac voltammetry. The analytical parameters (sensitivity, selectivity and reproducibility) are evaluated. Very good discrimination against the single-base mismatch A2143G, internal to the 23S rRNA gene of Helicobacter pylori, is observed. Moreover the system is successfully applied to the detection of complementary PCR amplicons. [Copyright &y& Elsevier]
- Published
- 2007
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6. Ir-CPI, a coagulation contact phase inhibitor from the tick Ixodes ricinus, inhibits thrombus formation without impairing hemostasis.
- Author
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Decrem Y, Rath G, Blasioli V, Cauchie P, Robert S, Beaufays J, Frère JM, Feron O, Dogné JM, Dessy C, Vanhamme L, and Godfroid E
- Subjects
- Animals, Blood Coagulation Factor Inhibitors chemistry, Disease Models, Animal, Factor XIIa metabolism, Factor XIa metabolism, Fibrinolysin metabolism, Fibrinolysis drug effects, Humans, Kallikreins metabolism, Male, Mice, Partial Thromboplastin Time, Protein Binding drug effects, Rats, Recombinant Proteins isolation & purification, Recombinant Proteins pharmacology, Sequence Analysis, Protein, Thrombin biosynthesis, Thrombosis pathology, Venous Thrombosis pathology, Venous Thrombosis prevention & control, Blood Coagulation drug effects, Blood Coagulation Factor Inhibitors pharmacology, Ixodes chemistry, Thrombosis prevention & control
- Abstract
Blood coagulation starts immediately after damage to the vascular endothelium. This system is essential for minimizing blood loss from an injured blood vessel but also contributes to vascular thrombosis. Although it has long been thought that the intrinsic coagulation pathway is not important for clotting in vivo, recent data obtained with genetically altered mice indicate that contact phase proteins seem to be essential for thrombus formation. We show that recombinant Ixodes ricinus contact phase inhibitor (Ir-CPI), a Kunitz-type protein expressed by the salivary glands of the tick Ixodes ricinus, specifically interacts with activated human contact phase factors (FXIIa, FXIa, and kallikrein) and prolongs the activated partial thromboplastin time (aPTT) in vitro. The effects of Ir-CPI were also examined in vivo using both venous and arterial thrombosis models. Intravenous administration of Ir-CPI in rats and mice caused a dose-dependent reduction in venous thrombus formation and revealed a defect in the formation of arterial occlusive thrombi. Moreover, mice injected with Ir-CPI are protected against collagen- and epinephrine-induced thromboembolism. Remarkably, the effective antithrombotic dose of Ir-CPI did not promote bleeding or impair blood coagulation parameters. To conclude, our results show that a contact phase inhibitor is an effective and safe antithrombotic agent in vivo.
- Published
- 2009
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7. The impact of gene knock-down and vaccination against salivary metalloproteases on blood feeding and egg laying by Ixodes ricinus.
- Author
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Decrem Y, Mariller M, Lahaye K, Blasioli V, Beaufays J, Zouaoui Boudjeltia K, Vanhaeverbeek M, Cérutti M, Brossard M, Vanhamme L, and Godfroid E
- Subjects
- Amino Acid Sequence, Animals, Feeding Behavior, Female, Fibrinolysis, Gene Library, Gene Silencing, Ixodes enzymology, Ixodes immunology, Male, Metalloproteases immunology, Metalloproteases metabolism, Molecular Sequence Data, Multigene Family, Oviposition, RNA Interference, Rabbits, Reverse Transcriptase Polymerase Chain Reaction methods, Salivary Proteins and Peptides genetics, Salivary Proteins and Peptides immunology, Sequence Alignment, Tick Infestations immunology, Weight Gain, Ixodes genetics, Metalloproteases genetics, Salivary Glands enzymology, Tick Infestations prevention & control, Vaccination methods
- Abstract
Two cDNAs coding homologous putative metalloproteases (Metis 1 and Metis 2, expected molecular weights of 55.6 and 56.0kDa, respectively) were identified from the hard tick Ixodes ricinus. The expression of Metis genes was induced in salivary glands during tick blood meal. RNA interference was used to assess the role of both Metis 1 and Metis 2 in tick feeding. It was found that salivary gland extracts lacking Metis 1-2 had a restricted ability to interfere with fibrinolysis. RNAi against Metis 1-2 also induced a high mortality rate. An immune reaction was raised in repeatedly bitten animals against Metis 1 and 2. Vaccination of hosts with the recombinant Metis 1 protein produced in a eukaryotic system partially interfered with completion of the blood meal. Although vaccination did not alter the survival rate or feeding time of ticks, their weight gain and oviposition rate were reduced. This will affect their reproductive fitness in the field. We believe this is the first report of an anti-tick vaccine trial using a metalloprotease derived from I. ricinus.
- Published
- 2008
- Full Text
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8. A family of putative metalloproteases in the salivary glands of the tick Ixodes ricinus.
- Author
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Decrem Y, Beaufays J, Blasioli V, Lahaye K, Brossard M, Vanhamme L, and Godfroid E
- Subjects
- Amino Acid Sequence, Animals, Arachnid Vectors enzymology, Arachnid Vectors genetics, Evolution, Molecular, Female, Ixodes genetics, Male, Metalloproteases genetics, Mice, Molecular Sequence Data, Rabbits, Salivary Glands enzymology, Salivary Proteins and Peptides genetics, Ixodes enzymology, Metalloproteases physiology, Multigene Family, Salivary Proteins and Peptides physiology
- Abstract
Ticks are obligate blood-feeding arachnids. During their long-lasting blood meal, they have to counteract the protective barriers and defense mechanisms of their host. These include tissue integrity, pain, hemostasis, and the inflammatory and immune reactions. Here, we describe a multigene family coding for five putative salivary metalloproteases induced during the blood meal of Ixodes ricinus. The evolutionary divergence inside the family was driven by positive Darwinian selection. This came together with individual variation of expression, functional heterogeneity, and antigenic diversification. Inhibition of the expression of some of these genes by RNA interference prevented completion of the tick blood meal and affected the ability of the tick saliva to interfere with host fibrinolysis. This family of proteins could therefore participate in the inhibition of wound healing after the tick bite, thereby facilitating the completion of the blood meal.
- Published
- 2008
- Full Text
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9. Variability and action mechanism of a family of anticomplement proteins in Ixodes ricinus.
- Author
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Couvreur B, Beaufays J, Charon C, Lahaye K, Gensale F, Denis V, Charloteaux B, Decrem Y, Prévôt PP, Brossard M, Vanhamme L, and Godfroid E
- Subjects
- Animals, Enzyme-Linked Immunosorbent Assay, Insect Proteins classification, Phylogeny, Properdin metabolism, Protein Binding, Reverse Transcriptase Polymerase Chain Reaction, Sepharose, Complement Inactivator Proteins metabolism, Insect Proteins metabolism, Ixodes metabolism
- Abstract
Background: Ticks are blood feeding arachnids that characteristically take a long blood meal. They must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. This is achieved by expressing batteries of salivary proteins coded by multigene families., Methodology/principal Findings: We report the in-depth analysis of a tick multigene family and describe five new anticomplement proteins in Ixodes ricinus. Compared to previously described Ixodes anticomplement proteins, these segregated into a new phylogenetic group or subfamily. These proteins have a novel action mechanism as they specifically bind to properdin, leading to the inhibition of C3 convertase and the alternative complement pathway. An excess of non-synonymous over synonymous changes indicated that coding sequences had undergone diversifying selection. Diversification was not associated with structural, biochemical or functional diversity, adaptation to host species or stage specificity but rather to differences in antigenicity., Conclusions/significance: Anticomplement proteins from I. ricinus are the first inhibitors that specifically target a positive regulator of complement, properdin. They may provide new tools for the investigation of role of properdin in physiological and pathophysiological mechanisms. They may also be useful in disorders affecting the alternative complement pathway. Looking for and detecting the different selection pressures involved will help in understanding the evolution of multigene families and hematophagy in arthropods.
- Published
- 2008
- Full Text
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10. Ir-LBP, an ixodes ricinus tick salivary LTB4-binding lipocalin, interferes with host neutrophil function.
- Author
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Beaufays J, Adam B, Menten-Dedoyart C, Fievez L, Grosjean A, Decrem Y, Prévôt PP, Santini S, Brasseur R, Brossard M, Vanhaeverbeek M, Bureau F, Heinen E, Lins L, Vanhamme L, and Godfroid E
- Subjects
- Amino Acid Sequence, Animals, Animals, Genetically Modified, Computer Simulation, Female, Host-Parasite Interactions genetics, Lipocalins genetics, Lipocalins metabolism, Lipocalins physiology, Models, Molecular, Molecular Sequence Data, Neutrophil Activation physiology, Protein Binding, Rabbits, Receptors, Leukotriene B4 chemistry, Receptors, Leukotriene B4 genetics, Receptors, Leukotriene B4 metabolism, Salivary Proteins and Peptides genetics, Salivary Proteins and Peptides metabolism, Salivary Proteins and Peptides physiology, Sequence Homology, Amino Acid, Tick Infestations immunology, Host-Parasite Interactions immunology, Ixodes immunology, Ixodes metabolism, Leukotriene B4 metabolism, Neutrophils physiology, Receptors, Leukotriene B4 physiology
- Abstract
Background: During their blood meal, ticks secrete a wide variety of proteins that can interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response., Methodology/principal Findings: We previously identified 14 new lipocalin genes in the tick Ixodes ricinus. One of them codes for a protein that specifically binds leukotriene B4 with a very high affinity (Kd: +/-1 nM), similar to that of the neutrophil transmembrane receptor BLT1. By in silico approaches, we modeled the 3D structure of the protein and the binding of LTB4 into the ligand pocket. This protein, called Ir-LBP, inhibits neutrophil chemotaxis in vitro and delays LTB4-induced apoptosis. Ir-LBP also inhibits the host inflammatory response in vivo by decreasing the number and activation of neutrophils located at the tick bite site. Thus, Ir-LBP participates in the tick's ability to interfere with proper neutrophil function in inflammation., Conclusions/significance: These elements suggest that Ir-LBP is a "scavenger" of LTB4, which, in combination with other factors, such as histamine-binding proteins or proteins inhibiting the classical or alternative complement pathways, permits the tick to properly manage its blood meal. Moreover, with regard to its properties, Ir-LBP could possibly be used as a therapeutic tool for illnesses associated with an increased LTB4 production.
- Published
- 2008
- Full Text
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11. Ixodes ricinus tick lipocalins: identification, cloning, phylogenetic analysis and biochemical characterization.
- Author
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Beaufays J, Adam B, Decrem Y, Prévôt PP, Santini S, Brasseur R, Brossard M, Lins L, Vanhamme L, and Godfroid E
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- Amino Acid Sequence, Animals, Cloning, Molecular, Conserved Sequence, Female, Gene Expression Profiling, Ixodes chemistry, Lipocalins isolation & purification, Molecular Sequence Data, Multigene Family, Rabbits, Sequence Homology, Amino Acid, Tick Infestations parasitology, Ticks genetics, Ixodes genetics, Lipocalins chemistry, Lipocalins genetics, Phylogeny
- Abstract
Background: During their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. Among these proteins, lipocalins play a major role in the modulation of the inflammatory response., Methodology/principal Findings: Screening a cDNA library in association with RT-PCR and RACE methodologies allowed us to identify 14 new lipocalin genes in the salivary glands of the Ixodes ricinus hard tick. A computational in-depth structural analysis confirmed that LIRs belong to the lipocalin family. These proteins were called LIR for "Lipocalin from I. ricinus" and numbered from 1 to 14 (LIR1 to LIR14). According to their percentage identity/similarity, LIR proteins may be assigned to 6 distinct phylogenetic groups. The mature proteins have calculated pM and pI varying from 21.8 kDa to 37.2 kDa and from 4.45 to 9.57 respectively. In a western blot analysis, all recombinant LIRs appeared as a series of thin bands at 50-70 kDa, suggesting extensive glycosylation, which was experimentally confirmed by treatment with N-glycosidase F. In addition, the in vivo expression analysis of LIRs in I. ricinus, examined by RT-PCR, showed homogeneous expression profiles for certain phylogenetic groups and relatively heterogeneous profiles for other groups. Finally, we demonstrated that LIR6 codes for a protein that specifically binds leukotriene B4., Conclusions/significance: This work confirms that, regarding their biochemical properties, expression profile, and sequence signature, lipocalins in Ixodes hard tick genus, and more specifically in the Ixodes ricinus species, are segregated into distinct phylogenetic groups suggesting potential distinct function. This was particularly demonstrated by the ability of LIR6 to scavenge leukotriene B4. The other LIRs did not bind any of the ligands tested, such as 5-hydroxytryptamine, ADP, norepinephrine, platelet activating factor, prostaglandins D2 and E2, and finally leukotrienes B4 and C4.
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- 2008
- Full Text
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12. Characterization of a novel salivary immunosuppressive protein from Ixodes ricinus ticks.
- Author
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Leboulle G, Crippa M, Decrem Y, Mejri N, Brossard M, Bollen A, and Godfroid E
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- Animals, CD28 Antigens biosynthesis, CD3 Complex biosynthesis, CHO Cells, Cell Division, Cells, Cultured, Cricetinae, Cytokines biosynthesis, DNA, Complementary metabolism, Dose-Response Relationship, Drug, Humans, Interferon-gamma biosynthesis, Interleukin-10 biosynthesis, Interleukin-5 biosynthesis, Ixodes, Macrophages metabolism, Mice, Mice, Inbred BALB C, Microscopy, Confocal, Protein Binding, Protein Structure, Tertiary, Salivary Glands metabolism, Spleen cytology, T-Lymphocytes metabolism, Th2 Cells metabolism, Immunosuppressive Agents pharmacology, Saliva metabolism, Salivary Proteins and Peptides biosynthesis, Salivary Proteins and Peptides chemistry
- Abstract
In tick salivary glands, several genes are induced during the feeding process, leading to the expression of new proteins. These proteins are typically secreted in tick saliva and are potentially involved in the modulation of the host immune and hemostatic responses. In a previous study, the construction and the analysis of a subtractive library led to the identification of Ixodes ricinus immunosuppressor (Iris), a novel protein, differentially expressed in I. ricinus salivary glands during the blood meal. In the present study, the data strongly suggest that this protein is secreted by tick salivary glands into the saliva. In addition, Iris is also found to modulate T lymphocyte and macrophage responsiveness by inducing a Th2 type response and by inhibiting the production of pro-inflammatory cytokines. In conclusion, these results suggest that Iris is an immunosuppressor, which might play an important role in the modulation of host immune response.
- Published
- 2002
- Full Text
- View/download PDF
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