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2. Rhabdomyosarcoma targeting with tuned porous silicon nanoparticles

Author

Dominguez‐Gil, Sofia, primary, Sala, Rita, additional, Morel, Victoria Judith, additional, Nguyen, Christophe, additional, Cheikh, Khaled El, additional, Morère, Alain, additional, Durand, Jean‐Olivier, additional, Rössler, Jochen, additional, Bernasconi, Michele, additional, Cunin, Frédérique, additional, and Gary‐Bobo, Magali, additional

Published
2024
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4. Variation in Pyrethroid Resistance Phenotypes in Anopheles darlingi in an Area with Residual Malaria Transmission: Warning of Suspected Resistance in French Guiana

Author

Vezenegho, Samuel, primary, Carinci, Romuald, additional, Issaly, Jean, additional, Nguyen, Christophe, additional, Gaborit, Pascal, additional, Ferraro, Laetitia, additional, Lacour, Guillaume, additional, Mosnier, Emilie, additional, Pommier de Santi, Vincent, additional, Epelboin, Yanouk, additional, Girod, Romain, additional, Briolant, Sebastien, additional, and Dusfour, Isabelle, additional

Published
2023
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9. Malaria hyperendemicity and risk for artemisinin resistance among illegal gold miners, French Guiana

Author

de Santi, Vincent Pommier, Djossou, Felix, Barthes, Nicolas, Bogreau, Herve, Hyvert, Georges, Nguyen, Christophe, Pelleau, Stephane, Legrand, Eric, Musset, Lise, Nacher, Mathieu, and Briolant, Sebastien

Subjects
Gold miners -- Health aspects, Drug resistance -- Forecasts and trends, Antiparasitic agents -- Usage, Malaria -- Distribution, Market trend/market analysis, Company distribution practices, Health
Abstract

Malaria control programs on the Guiana Shield, a region of South America, are challenged by migrant populations looking for gold. Since 2008, the 'Harpie' operation to control and reduce illegal [...]

Published
2016
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11. Encapsulation of Hydrophobic Porphyrins into Biocompatible Nanoparticles: An Easy Way to Benefit of Their Two-Photon Phototherapeutic Effect without Hydrophilic Functionalization

Author

Shi, Limiao, primary, Nguyen, Christophe, additional, Daurat, Morgane, additional, Richy, Nicolas, additional, Gauthier, Corentin, additional, Rebecq, Estelle, additional, Gary-Bobo, Magali, additional, Cammas-Marion, Sandrine, additional, Mongin, Olivier, additional, Paul-Roth, Christine O., additional, and Paul, Frédéric, additional

Published
2022
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15. Loïc Pagès, founding scientist in root ecology and modelling

Author

Barczi, Jean-François, Beroueg, Amira, Buck-Sorlin, Gerhard, Couvreur, Valentin, Danjon, Frédéric, Delory, Benjamin M., Doussan, Claude, de Swaef, Tom, Draye, Xavier, Drouet, Jean-Louis, Dupuy, Lionel, Garre, Sarah, Gérard, Frédéric, Heymans, Adrien, Hinsinger, Philippe, Javaux, Mathieu, Koch, Axelle, Landl, Magdalena, Lecompte, François, Daniel, Leitner, Lobet, Guillaume, Lynch, Jonathan, Martre, Pierre, Meredieu, Céline, Meunier, Felicien, Mollier, Alain, Muller, Bertrand, Nguyen, Christophe, Picon-Cochard, Catherine, Postma, Johannes A., Pradal, Christophe, Rees, Frédéric, Richard-Molard, Céline, Roose, Tiina, Saint-Cast, Clément, Schnepf, Andrea, Thaler, Philippe, Vanderborght, Jan, Wu, Lianhai, Zhou, Xiaoran, Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut de Recherche en Horticulture et Semences (IRHS), Université d'Angers (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Université Catholique de Louvain = Catholic University of Louvain (UCL), Biodiversité, Gènes & Communautés (BioGeCo), Université de Bordeaux (UB)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Leuphana University of Lüneburg, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Research Institute for Agricultural, Fisheries and Food (ILVO), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ikerbasque - Basque Foundation for Science, Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Forschungszentrum Jülich GmbH | Centre de recherche de Juliers, Helmholtz-Gemeinschaft = Helmholtz Association, Simulationswerkstatt, Pennsylvania State University (Penn State), Penn State System, Écophysiologie des Plantes sous Stress environnementaux (LEPSE), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Universiteit Gent = Ghent University (UGENT), Interactions Sol Plante Atmosphère (UMR ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Unité Mixte de Recherche sur l'Ecosystème Prairial - UMR (UREP), VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Amélioration génétique et adaptation des plantes méditerranéennes et tropicales (UMR AGAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro, Département Systèmes Biologiques (Cirad-BIOS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), University of Southampton, Département Performances des systèmes de production et de transformation tropicaux (Cirad-PERSYST), Rothamsted Research, Biotechnology and Biological Sciences Research Council (BBSRC), UCL - SST/ELI/ELIE - Environmental Sciences, and UCL - SST/ELI/ELIA - Agronomy

Subjects
0106 biological sciences, [SDV]Life Sciences [q-bio], 04 agricultural and veterinary sciences, Plant Science, Genetics and Molecular Biology (miscellaneous), 01 natural sciences, Biochemistry, Genetics and Molecular Biology (miscellaneous), Biochemistry, Modeling and Simulation, 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, ddc:004, Agronomy and Crop Science, ComputingMilieux_MISCELLANEOUS, 010606 plant biology & botany
Abstract

Root system scientists strive to understand how a single root, emerging from a plant’s seed, can form a complex, dynamic and plastic network of thousands of individual roots. They investigate how such a network is ideally suited to perform a number of functions required for the harmonious development of the whole plant. Everyone in the community also knows how complicated it can be to study root systems, with tasks ranging from digging plants out of the soil, creating experimental set-ups that allow the observation of the roots, to quantifying the root network itself or the processes underlying its formation. Within the community, there is one person, Dr Loïc Pagès, who has been working on all these tasks for many years, and who has moved the field forward numerous times. On the occasion of his soon-to-be retirement, we would like to express our appreciation to him via this editorial.

Published
2021

16. Malaria in French Guiana linked to illegal gold mining

Author

de Santi, Vincent Pommier, Dia, Aissata, Adde, Antoine, Hyvert, Georges, Galant, Julien, Mazevet, Michel, Nguyen, Christophe, Vezenegho, Samuel B., Dusfour, Isabelle, Girod, Romain, and Briolant, Sebastien

Subjects
Gold mines and mining -- Health aspects, Malaria -- Distribution, Public health -- Forecasts and trends, Market trend/market analysis, Company distribution practices, Health
Abstract

To the Editor: French Guiana, an overseas territory of France and part of the European Union, is located on the northeast coast of South America (Figure). During 20082014, the number [...]

Published
2016

18. Phytoavailability of Cd, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Tl and Zn in Arable Crop Systems Amended for 13 to 15 Years with Organic Waste Products

Author

Michaud, Aurélia, Sappin-Didier, Valérie, Cambier, Philippe, Nguyen, Christophe, Janot, Noémie, Montenach, Denis, Filipovic, Lana, Deltreil, Valentin, Houot, Sabine, Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Sol Agro et hydrosystème Spatialisation (SAS), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Interactions Sol Plante Atmosphère (UMR ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Service d'expérimentation agronomique et viticole (COLM AGRO VITI UE), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Zagreb, Veolia Recherche et Innovation, and ANR-11-INBS-0001,ANAEE-FR,ANAEE-Services(2011)

Subjects
long-term field experiment, lcsh:Agriculture, organic waste recycling, micronutrients, [SDE]Environmental Sciences, [SDV.SA.AGRO]Life Sciences [q-bio]/Agricultural sciences/Agronomy, lcsh:S, trace elements, phytoavailability, [SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study
Abstract

International audience; Repeated applications of organic waste products (OWP) are a source of trace elements (TE) inputs to agricultural topsoils. The present study aimed at (i) assessing the effects of repeated OWP inputs on the chemical properties of topsoils in two long-term field experiments (13 and 15 years; calcareous and non-calcareous soils), (ii) evaluating TE phytoavailability and their transfer to grain (winter wheat and maize) and (iii) identifying the underlying factors causing alterations of TE phytoavailability. In both field experiments, receiving compliant or slightly high doses of OWP in compliance with regulations, OWP and soil physicochemical properties and TE concentrations in soils and grains were determined. In situ phytoavailability of TE was assessed at two juvenile crop growth stages by analyzing TE concentrations in shoot plantlets. Depending on the OWP input amount, results showed that compared to the soil receiving no organic amendment, repeated OWP inputs significantly increased soil organic carbon content, pH, cation exchange capacity, total soil Cu, Mo and Zn concentration and the phytoavailability of Mo, while the phytoavailability of Cd, Mn, Ni and Tl was significantly reduced. No notable effect was observed for Cr, Cu, Hg, Pb and Zn phytoavailability. Statistical approaches suggested that due to the repeated OWP applications, increased soil organic carbon content and pH, were likely responsible for decreased TE phytoavailability (e.g., Cd).

Published
2021

19. Loïc Pagès, founding scientist in root ecology and modelling

Author

UCL - SST/ELI/ELIE - Environmental Sciences, UCL - SST/ELI/ELIA - Agronomy, Barczi, Jean-François, Beroueg, Amira, Buck-Sorlin, Gerhard, Couvreur, Valentin, Danjon, Frédéric, Delory, Benjamin M., Doussan, Claude, De Swaef, Tom, Draye, Xavier, Drouet, Jean-Louis, Dupuy, Lionel, Garre, Sarah, Gérard, Frédéric, Heymans, Adrien, Hinsinger, Philippe, Javaux, Mathieu, Koch, Axelle, Landl, Magdalena, Lecompte, François, Leitner, Daniel, Lobet, Guillaume, Lynch, Jonathan, Martre, Pierre, Meredieu, Céline, Meunier, Felicien, Mollier, Alain, Muller, Bertrand, Nguyen, Christophe, Picon-Cochard, Catherine, Postma, Johannes A., Pradal, Christophe, Rees, Frédéric, Richard-Molard, Céline, Roose, Tiina, Saint Cast, Clément, Schnepf, Andrea, Thaler, Philippe, Vanderborght, Jan, Wu, Lianhai, Zhou, Xiaoran, UCL - SST/ELI/ELIE - Environmental Sciences, UCL - SST/ELI/ELIA - Agronomy, Barczi, Jean-François, Beroueg, Amira, Buck-Sorlin, Gerhard, Couvreur, Valentin, Danjon, Frédéric, Delory, Benjamin M., Doussan, Claude, De Swaef, Tom, Draye, Xavier, Drouet, Jean-Louis, Dupuy, Lionel, Garre, Sarah, Gérard, Frédéric, Heymans, Adrien, Hinsinger, Philippe, Javaux, Mathieu, Koch, Axelle, Landl, Magdalena, Lecompte, François, Leitner, Daniel, Lobet, Guillaume, Lynch, Jonathan, Martre, Pierre, Meredieu, Céline, Meunier, Felicien, Mollier, Alain, Muller, Bertrand, Nguyen, Christophe, Picon-Cochard, Catherine, Postma, Johannes A., Pradal, Christophe, Rees, Frédéric, Richard-Molard, Céline, Roose, Tiina, Saint Cast, Clément, Schnepf, Andrea, Thaler, Philippe, Vanderborght, Jan, Wu, Lianhai, and Zhou, Xiaoran

Abstract

Root system scientists strive to understand how a single root, emerging from a plant’s seed, can form a complex, dynamic and plastic network of thousands of individual roots. They investigate how such a network is ideally suited to perform a number of functions required for the harmonious development of the whole plant. Everyone in the community also knows how complicated it can be to study root systems, with tasks ranging from digging plants out of the soil, creating experimental set-ups that allow the observation of the roots, to quantifying the root network itself or the processes underlying its formation. Within the community, there is one person, Dr Loïc Pagès, who has been working on all these tasks for many years, and who has moved the field forward numerous times. On the occasion of his soon-to-be retirement, we would like to express our appreciation to him via this editorial.

Published
2021

20. Variation in Pyrethroid Resistance Phenotypes in Anopheles darlingi in an Area with Residual Malaria Transmission: Warning of Suspected Resistance in French Guiana

Author

Vezenegho, Samuel, Carinci, Romuald, Issaly, Jean, Nguyen, Christophe, Gaborit, Pascal, Ferraro, Laetitia, Lacour, Guillaume, Mosnier, Emilie, Pommier de Santi, Vincent, Epelboin, Yanouk, Girod, Romain, Briolant, Sebastien, Dusfour, I., Vectopôle Amazonien Emile Abonnenc [Cayenne, Guyane française], Institut Pasteur de la Guyane, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), Institut de Recherche Biomédicale des Armées [Antenne Marseille] (IRBA), Vecteurs - Infections tropicales et méditerranéennes (VITROME), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut de Recherche Biomédicale des Armées [Brétigny-sur-Orge] (IRBA), Sciences Economiques et Sociales de la Santé & Traitement de l'Information Médicale (SESSTIM - U1252 INSERM - Aix Marseille Univ - UMR 259 IRD), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier Andrée Rosemon [Cayenne, Guyane Française], Centre d'épidémiologie et de santé publique des armées [Marseille] (CESPA), Service de Santé des Armées, Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP), Maladies infectieuses et vecteurs : écologie, génétique, évolution et contrôle (MIVEGEC), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Université de Montpellier (UM), Département de Santé Globale - Department Global Health, Institut Pasteur [Paris] (IP)-Université Paris Cité (UPCité), and This work was funded by the 'Agence Régionalede Santé de la Guyane' through a yearly grant to support vector control and by the French Army (Grant LR607e). YE and GL salaries were funded by FEDER 'CONTROLE,' project n° Synergie: GY0010695.

Subjects
[SDV.MHEP.ME]Life Sciences [q-bio]/Human health and pathology/Emerging diseases, Infectious Diseases, [SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, Virology, [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology, Parasitology, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology
Abstract

Anopheles darlingi is the main vector of malaria in South America. In French Guiana, malaria transmission occurs inland and along the rivers with a regular reemergence in the lower Oyapock area. Control against malaria vectors includes indoor residual spraying of deltamethrin and the distribution of long-lasting impregnated bednets. In this context, the level of resistance to pyrethroids was monitored for 4 years using CDC bottle tests in An. darlingi populations. A loss of susceptibility to pyrethroids was recorded with 30-minute knock-down measured as low as 81%. However, no pyrethroid molecular resistance was found by sequencing a 170 base pair fragment of the S6 segment of domain II of the voltage-gated sodium channel gene. Fluctuation of resistance phenotypes may be influenced by the reintroduction of susceptible alleles from sylvatic populations or by other mechanisms of metabolic resistance.

Published
2020

26. Polythiophenes with Cationic Phosphonium Groups as Vectors for Imaging, siRNA Delivery, and Photodynamic Therapy

Author

Lichon, Laure, primary, Kotras, Clément, additional, Myrzakhmetov, Bauyrzhan, additional, Arnoux, Philippe, additional, Daurat, Morgane, additional, Nguyen, Christophe, additional, Durand, Denis, additional, Bouchmella, Karim, additional, Ali, Lamiaa Mohamed Ahmed, additional, Durand, Jean-Olivier, additional, Richeter, Sébastien, additional, Frochot, Céline, additional, Gary-Bobo, Magali, additional, Surin, Mathieu, additional, and Clément, Sébastien, additional

Published
2020
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30. Encapsulation of upconversion nanoparticles in periodic mesoporous organosilicas

Author

Agencia Estatal de Investigación (España), Agence Nationale de la Recherche (France), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Rahmani, Saher, Mauriello Jimenez, Chiara, Aggad, Dina, González-Mancebo, Daniel, Ocaña, Manuel, Ali, Lamiaa M. A., Nguyen, Christophe, Becerro, Ana Isabel, Francolon, Nadège, Oliveiro, Erwan, Boyer, Damien, Mahiou, Rachid, Raehm, Laurence, Gary-Bobo, Magali, Durand, Jean-Olivier, Charnay, Clarence, Agencia Estatal de Investigación (España), Agence Nationale de la Recherche (France), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Rahmani, Saher, Mauriello Jimenez, Chiara, Aggad, Dina, González-Mancebo, Daniel, Ocaña, Manuel, Ali, Lamiaa M. A., Nguyen, Christophe, Becerro, Ana Isabel, Francolon, Nadège, Oliveiro, Erwan, Boyer, Damien, Mahiou, Rachid, Raehm, Laurence, Gary-Bobo, Magali, Durand, Jean-Olivier, and Charnay, Clarence

Abstract

1) Background: Nanomedicine has recently emerged as a promising field, particularly for cancer theranostics. In this context, nanoparticles designed for imaging and therapeutic applications are of interest. We, therefore, studied the encapsulation of upconverting nanoparticles in mesoporous organosilica nanoparticles. Indeed, mesoporous organosilica nanoparticles have been shown to be very efficient for drug delivery, and upconverting nanoparticles are interesting for near-infrared and X-ray computed tomography imaging, depending on the matrix used. (2) Methods: Two different upconverting-based nanoparticles were synthesized with Yb3+-Er3+ as the upconverting system and NaYF4 or BaLuF5 as the matrix. The encapsulation of these nanoparticles was studied through the sol-gel procedure with bis(triethoxysilyl)ethylene and bis(triethoxysilyl)ethane in the presence of CTAB. (3) Results: with bis(triethoxysilyl)ethylene, BaLuF5: Yb3+-Er3+, nanoparticles were not encapsulated, but anchored on the surface of the obtained mesoporous nanorods BaLuF5: Yb3+-Er3+@Ethylene. With bis(triethoxysilyl)ethane, BaLuF5: Yb3+-Er3+ and NaYF4: Yb3+-Er3+nanoparticles were encapsulated in the mesoporous cubic structure leading to BaLuF5: Yb3+-Er3+@Ethane and NaYF4: Yb3+-Er3+@Ethane, respectively. (4) Conclusions: upconversion nanoparticles were located on the surface of mesoporous nanorods obtained by hydrolysis polycondensation of bis(triethoxysilyl)ethylene, whereas encapsulation occurred with bis(triethoxysilyl)ethane. The later nanoparticles NaYF4: Yb3+-Er3+@Ethane or BaLuF5: Yb3+-Er3+@Ethane were promising for applications with cancer cell imaging or X-ray-computed tomography respectively.

Published
2019

31. PEPOP: new approaches to mimic non-continous epitopes

Author

Demolombe, Vincent, de Brevern, Alexandre, Felicori, Liza, NGuyen, Christophe, de Avila, Ricardo Andrez Machado, Valera, Lionel, Jardin-Watelet, Bénédicte, Lavigne, Géraldine, Lebreton, Aurélien, Molina, Franck, and Moreau, Violaine

Subjects
Vegetal Biology, Peptide design, discontinuous and continuous epitope, B-cell epitope, Ag-Ab interaction, IPP, protein surface, structural bioinformatics, immunogenicity, antigenicity, molecular mimicry, Biologie végétale
Abstract

Bioinformatics methods are helpful to identify new molecules for diagnostic or therapeutic applications. For example, the use of peptides capable of mimicking binding sites has several benefits as replacing a protein difficult to produce, or toxic. Using peptides is less expensive. Peptides are easier to manipulate, and can be used as drugs. Continuous epitope predicted by bioinformatics tools are commonly used and these sequential epitopes are used as such in further experiments. Numerous discontinuous epitope predictors have been developed but only two bioinformatics tools proposed so far to predict peptide sequences: Superficial and PEPOP. PEPOP can generate series of peptide sequences that can replace continuous or discontinuous epitopes in their interaction with their cognate antibody. We have developed an improved version of PEPOP dedicated to answer to the experimentalists' need for a tool able to handle proteins and to turn them into peptides. The PEPOP web site has been reorganized by peptide prediction category and is therefore better formulated to experimental designs. Since the first version of PEPOP, 32 new methods of peptide design were developed. In total, PEPOP proposes 35 methods in which 34 deal specifically with discontinuous epitopes, the most represented epitope type in nature. We present the user-friendly, well-structured web-site of PEPOP and its validation through the use of predicted immunogenic or antigenic peptides mimicking discontinuous epitopes in different experimental ways. PEPOP proposes 35 methods of peptide design to guide experimentalists in using peptides potentially capable of replacing the cognate protein in its interaction with an Ab.

Published
2018

32. Les éléments traces : bilan des contaminations des parcelles et des récoltes sur le réseau Quasaprove

Author

Denaix, Laurence, Nguyen, Christophe, Vivien, Emma, Donnat, Emilie, Meleard, Benoît, Grignon, Guénolé, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Association de Coordination Technique Agricole (ACTA), ARVALIS - Institut du végétal [Paris], and CASDAR QUASAGRO

Subjects
[SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
2018

33. Encapsulation of Upconversion Nanoparticles in Periodic Mesoporous Organosilicas

Author

Rahmani, Saher, primary, Mauriello Jimenez, Chiara, additional, Aggad, Dina, additional, González-Mancebo, Daniel, additional, Ocaña, Manuel, additional, M. A. Ali, Lamiaa, additional, Nguyen, Christophe, additional, Becerro Nieto, Ana Isabel, additional, Francolon, Nadège, additional, Oliveiro, Erwan, additional, Boyer, Damien, additional, Mahiou, Rachid, additional, Raehm, Laurence, additional, Gary-Bobo, Magali, additional, Durand, Jean-Olivier, additional, and Charnay, Clarence, additional

Published
2019
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34. Efficient Photodynamic Therapy of Prostate Cancer Cells through an Improved Targeting of the Cation-Independent Mannose 6-Phosphate Receptor

Author

Bouffard, Elise, primary, Mauriello Jimenez, Chiara, additional, El Cheikh, Khaled, additional, Maynadier, Marie, additional, Basile, Ilaria, additional, Raehm, Laurence, additional, Nguyen, Christophe, additional, Gary-Bobo, Magali, additional, Garcia, Marcel, additional, Durand, Jean-Olivier, additional, and Morère, Alain, additional

Published
2019
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35. Porphyrin‐based bridged silsesquioxane nanoparticles for targeted two‐photon photodynamic therapy of zebrafish xenografted with human tumor

Author

Dib, Soraya, primary, Aggad, Dina, additional, Mauriello Jimenez, Chiara, additional, Lakrafi, Ahmed, additional, Hery, Guillaume, additional, Nguyen, Christophe, additional, Durand, Denis, additional, Morère, Alain, additional, El Cheikh, Khaled, additional, Sol, Vincent, additional, Chaleix, Vincent, additional, Dominguez Gil, Sofia, additional, Bouchmella, Karim, additional, Raehm, Laurence, additional, Durand, Jean‐Olivier, additional, Boufatit, Makhlouf, additional, Cattoën, Xavier, additional, Wong Chi Man, Michel, additional, Bettache, Nadir, additional, and Gary‐Bobo, Magali, additional

Published
2019
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36. PEPOP: Computational design of immunogenic peptides

Author

Laune Daniel, Villard Sylvie, Novali Nicolas, Nguyen Christophe, Piquer Dominique, Fleury Cécile, Moreau Violaine, Granier Claude, and Molina Franck

Subjects
Computer applications to medicine. Medical informatics, R858-859.7, Biology (General), QH301-705.5
Abstract

Abstract Background Most methods available to predict protein epitopes are sequence based. There is a need for methods using 3D information for prediction of discontinuous epitopes and derived immunogenic peptides. Results PEPOP uses the 3D coordinates of a protein both to predict clusters of surface accessible segments that might correspond to epitopes and to design peptides to be used to raise antibodies that target the cognate antigen at specific sites. To verify the ability of PEPOP to identify epitopes, 13 crystallographically defined epitopes were compared with PEPOP clusters: specificity ranged from 0.75 to 1.00, sensitivity from 0.33 to 1.00, and the positive predictive value from 0.19 to 0.89. Comparison of these results with those obtained with two other prediction algorithms showed comparable specificity and slightly better sensitivity and PPV. To prove the capacity of PEPOP to predict immunogenic peptides that induce protein cross-reactive antibodies, several peptides were designed from the 3D structure of model antigens (IA-2, TPO, and IL8) and chemically synthesized. The reactivity of the resulting anti-peptides antibodies with the cognate antigens was measured. In 80% of the cases (four out of five peptides), the flanking protein sequence process (sequence-based) of PEPOP successfully proposed peptides that elicited antibodies cross-reacting with the parent proteins. Polyclonal antibodies raised against peptides designed from amino acids which are spatially close in the protein, but separated in the sequence, could also be obtained, although they were much less reactive. The capacity of PEPOP to design immunogenic peptides that induce antibodies suitable for a sandwich capture assay was also demonstrated. Conclusion PEPOP has the potential to guide experimentalists that want to localize an epitope or design immunogenic peptides for raising antibodies which target proteins at specific sites. More successful predictions of immunogenic peptides were obtained when a peptide was continuous as compared with peptides corresponding to discontinuous epitopes. PEPOP is available for use at http://diagtools.sysdiag.cnrs.fr/PEPOP/.

Published
2008
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37. Outflow mechanisms after deep sclerectomy with two different designs of collagen implant in an animal model

Author

Nguyen, Christophe, Boldea, Radu, Roy, Sylvain, Shaarawy, Tarek, Uffer, Sylvie, Mermoud, André, Nguyen, Christophe, Boldea, Radu, Roy, Sylvain, Shaarawy, Tarek, Uffer, Sylvie, and Mermoud, André

Abstract

Background: To study experimentally two different shapes of collagen implants (CI) used in deep sclerectomy (DS). The ability to promote drainage vessels, outflow mechanisms, success rates, and biodegradability, were studied prospectively in an animal model. Materials and methods: DS was performed in 20 eyes of ten rabbits. Each rabbit randomly received a cylindrical CI in one eye, while the other eye received a flat CI. Intraocular pressure (IOP) measurement, ultrasound biomicroscopy (UBM) examination of DS site and simultaneous fluorescein and indocyanin green anterior-segment angiography were performed preoperatively, at 1 and 2 weeks, 1, 2, 3, 6 and 9 months for each eye. At the end of the follow-up period, outflow facility (OF) was measured and histological examinations of the filtration site were performed. Results: In the cylindrical implant group, IOP significantly dropped from a mean preoperative value of 14.8±2.2mmHg to a mean postoperative values of 10.9±3.3, 12.5±2.2, 11.8±2.6, 11.2±2.3, 10.7±1.9, 14.0± 3.2, 12.6±2.4mmHg at 1, 2 weeks, and 1, 2, 3, 6, and 9 months, respectively. In the flat CI group, IOP significantly dropped from a mean preoperative value of 14.1±1.8mmHg to a mean postoperative values of 10.4±2.7, 12.7±1.9, 12.5±3.2, 11.2±1.6, 11.6±1.8, 11.5±2.3, 11.0±2.2mmHg at 1, 2 weeks, and at 1, 2, 3, 6, and 9 months, respectively. UBM images showed a gradual resorption of both type of CI during the first 3 months, and angiographies showed progressive growth of drainage vessels around the filtration site in both groups. The mean OF 9 months postoperatively for the cylindrical CI was 0.53 (SD ± 0.23) ml/min per mmHg and was 0.56 (SD±0.17) ml/min per mmHg for the flat CI (P=0.6). Histological examination revealed excellent biocompatibilty and a high density of drainage vessels in the sclera around the operative site in both groups. Conclusion: Using IOP and OF measurements, UBM, angiography, and histology, we were able to compare two types of CI used

Published
2018

38. Contamination of durum wheat by cadmium : lessons from the field

Author

Nguyen, Christophe, Gourdain, Emmanuelle, Grignon, Guénolé, Barrier-Guillot, Bruno, Meleard, Benoit, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), ARVALIS - Institut du végétal [Paris], and Interactions Sol Plante Atmosphère (ISPA)

Subjects
contamination, blé dur, [SDV]Life Sciences [q-bio], hard wheat, cadmiun, food and beverages
Abstract

Contamination of food crops by cadmium (Cd) is a major concern, particularly for durum wheat, which is widely consumed and which accumulates this toxic metal to a greater extent than bread wheat. Following the assessment of the risks to human health related to the presence of cadmium in foodstuffs, the European Commission intended to reduce the maximum content of Cd in wheat from 0.2 to 0.1 mg/kg grain. France is in the top 5 of European countries for the production of durum wheat and the project of a lower regulation limit for Cd stressed the urgent need i) to characterize the risk that harvests could exceed the new limit, ii) to identify, in the field, the major factors controlling the level of contamination. For that purpose, a specific project 'Cadur' was conducted between 2011 and 2014 in France. Samples of grains were collected in 2011, 2012 and 2013 among farmers of the different areas of production. The median value of Cd in durum wheat grain was 0.07 mg/kg with less than 5% of samples above the 0.2 mg/kg limit but 25% above 0.1 mg/kg (n=244). However, there were strong variations depending on the geographical areas and for some of them, up to 60% of the samples exceeded 0.1 mg Cd /kg. In order to understand the source of these variations, trials crossing cultivars and the areas of production were investigated. The cultivars were estimated to be responsible of 10-25% of the variation of the grain Cd concentration against 60-70% for the location of the culture. The effect of the location was mainly due to the concentration of Cd in the soil and to the soil pH. A statistical model with these two explanatory variables was able to explain 57% of the variability of the Cd concentration in the grains. Some of the durum wheat cultivars commonly grown in France were assessed with respect to their ability to accumulate Cd. It was found that the high:low ratio for the Cd content in grains was around 1.5 when cultivars were grown on the same soils. Contrary to Canadian cultivars, in France, no specific genetic selection has yet been performed to lower the contamination by Cd. Nitrogen fertilization was shown to have a significant effect, both by the dose and by the timing of application, presumably by modifying the mobility of Cd in the soil. Increasing N supply from 200 to 250 kg N/ha increased the Cd in grains by 20% and by 25% if the total N reached 300 kg N/ha. However, if the additional N was applied as two applications including a late one instead of a single dose, the increase in the grain contamination was not significant for a total of 250 kg N/ha. These studies confirm that both the soil conditions (Cd content, pH) and the cultivars are key points for controlling the contamination of durum wheat by Cd. French cultivars have the potential to be genetically selected to improve their ability to exclude Cd from the grain. They also have to be carefully chosen depending on the local bioavailability of Cd in soil, which can be in part, managed by controlling the pH and the nitrogen fertilisation. Funded by the projects 'Cadur', Arvalis-Inra and ANR-15-CE21-0001-04 'Cadon'

Published
2017

39. SimTraces a numerical simulator for predicting the accumulation of trace elements by crops

Author

Nguyen, Christophe, Bruchou, Claude, Cornu, Jean-Yves, Launay, Marie, Laporte, Marie-Aline, LIN, Zhongbing, Maron, Ronan, Liñero, Olaia, Pages, Loic, Ripoche, Dominique, Schneider, André, Sirguey, Catherine, Sterckeman, Thibault, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Biostatistique et Processus Spatiaux (BioSP), Institut National de la Recherche Agronomique (INRA), Agroclim (AGROCLIM), Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH), Laboratoire Sols et Environnement (LSE), and Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)

Subjects
[SDV]Life Sciences [q-bio], [SDE]Environmental Sciences
Abstract

International audience; General presentation of the Simtraces model to predict the soil to plant transfer of trace elements

Published
2017

40. Computational B-cell epitope identification and production of neutralizing murine antibodies against Atroxlysin-I

Author

Kozlova, Edgar Ernesto Gonzalez, primary, Cerf, Loïc, additional, Schneider, Francisco Santos, additional, Viart, Benjamin Thomas, additional, NGuyen, Christophe, additional, Steiner, Bethina Trevisol, additional, de Almeida Lima, Sabrina, additional, Molina, Franck, additional, Duarte, Clara Guerra, additional, Felicori, Liza, additional, Chávez-Olórtegui, Carlos, additional, and Machado-de-Ávila, Ricardo Andrez, additional

Published
2018
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41. Partitioning of nutrients and non-essential elements in Swiss chards cultivated in open-air plots

Author

Liñero, Olaia, Cidad, Maite, Carrero, Jose Antonio, Nguyen, Christophe, De Diego, Alberto, Liñero, Olaia, Cidad, Maite, Carrero, Jose Antonio, Nguyen, Christophe, and De Diego, Alberto

Abstract

The uptake of metals by plants and their partitioning between different organs is an important issue in fields like plant ecology, phytochemistry, phytoremediation and, in the case of plants with edible parts, food quality. In this work a five-month field experiment was carried out to investigate the uptake and partitioning of 20 elements (Mg, K, Ca, Na, Mn, Fe, Co, Cu, Zn, Mo, Sr, Ba, Al, Ti, V, Cr, As, Cd, TI and Pb) by Swiss chards (Beta vulgaris). The effect of the harvesting time on the accumulation of these elements in roots, stalks and leaf blades was studied using plants cultivated in two different but adjacent air-open plots subjected to conventional or organic farming techniques. Plants were collected at six growth stages during their production cycle and samples were analysed by ICP-MS after microwave assisted acid digestion. Toxic elements (except Cd) were mainly immobilised in roots, whereas essential elements were translocated to aboveground organs. In general, the element concentrations in plant organs decreased with time. The use of organic fertilisers promoted the presence of nutrients in blades and stalks. Pb and Cd concentrations in the edible parts were always below the maximum levels set by the European Union.

Published
2017

42. Variability in grain cadmium concentration among durum wheat cultivars: impact of aboveground biomass partitioning

Author

Yan, Bofang, Perrier, Fanny, Pokrovsky, Oleg S., Nguyen, Christophe, Cornu, Jean-Yves, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Géosciences Environnement Toulouse (GET), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Vegetal Biology, céréale, accumulation du cadmium, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, grain, ComputingMilieux_MISCELLANEOUS, Biologie végétale, Sciences agricoles, Agricultural sciences
Abstract

International audience

Published
2016

43. Does nitrogen supply impact the cadmium fluxes to developing durum wheat (Triticum turgidum L. subsp. durum) grains?

Author

Yan, Bofang, Nguyen, Christophe, Pokrovsky, Oleg, Cornu, Jean-Yves, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Géosciences Environnement Toulouse (GET), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
céréale, cadmium, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, traçage isotopique, grain, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

44. A meta-model to predict the phytoavailability of cadmium in French agricultural soils

Author

Schneider, André, LIN, Zhongbing, Sterckeman, Thibault, Nguyen, Christophe, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Laboratoire Sols et Environnement (LSE), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), and Interactions Sol Plante Atmosphère (ISPA)

Subjects
[SDV]Life Sciences [q-bio]
Abstract

Predicting the phytoavailability of toxic trace elements such as cadmium (M) in soils is an important issue for crop quality. A set of partial differential equations can be derived for simulating the root influx of M2+, the transport by diffusion and convection, the kinetics of sorption/desorption, and the kinetics of complexation in solution, for the free ionic species (M2+), for a mean ligand, and for the complex. The aim of this study was to develop a simple meta-model that would be easier to handle than these partial differential equations. d and are out of equilibrium in a reaction layer of thickness μ < d; in this reaction layer the concentration of the complex is assumed constant, and the association rate of the complex is neglected. Under these assumptions and for two extreme behaviors of the complex, i.e. when complex is totally labile (μ=0) or totally inert (μ=d), the analytical equation for calculating the concentration of trace element at the root surface, and therefore the uptake, was derived. For intermediate complex lability (0

Published
2015

45. Understanding the partitioning and concentration of trace elements in the plant organs of some food crops: influence of the plant allometry and of the growth stage

Author

Nguyen, Christophe, De Diego Rodríguez, Alberto, Química Analítica;;Kimika Analitikoa, Química analítica, Kimika analitikoa, Liñero Campo, Olaia, Nguyen, Christophe, De Diego Rodríguez, Alberto, Química Analítica;;Kimika Analitikoa, Química analítica, Kimika analitikoa, and Liñero Campo, Olaia

Abstract

246 p., This PhD Thesis has been carried out as a co-tutelle between the UPV/EHU and the University of Bordeaux, in the framework of the Cross-Border Euroregional Campus of International Excellence IdEx Bordeaux ¿ Euskampus. The work is focused on the accumulation of essential and non-essential elements, paying special attention to the edible part of the plants, in terms of food safety and human health. This Thesis work has been divided in two main parts: The first one is related to a field experiment performed in open-air plots, where Swiss chards and tomato plants were grown from seedlings to maturity in natural soil during five months, using organic or conventional agricultural practices. Plants were harvested at six different growth stages and the total concentrations of 27 elements were measured in all plant organs. The objective was to study the partitioning of the elements between the plant organs, depending on the plant age and on the cultivation practice. The second part of the Thesis is devoted to the understanding and modelling of the partitioning of Cd in sunflowers at the reproductive stages. Sunflowers were grown in a nutrient solution at low Cd availability consistent with that found in the field, from germination to maturity. During the reproductive period, five samplings were carried out to investigate the partitioning of the total Cd between plant organs and the origin of the Cd allocated to seeds (root uptake vs. remobilization from other plant organs). A the flower bud and grain filling stages, the partitioning of the Cd recently taken up between the different plant organs was followed and modelled by exposing several plants for three days to a 111Cd enriched nutrient solution. The roles of the transpiration and of the plant allometry were specially investigated.

Published
2016

46. Différences inter-variétales d’accumulation de Cd chez le blé dur (Triticum durum sp.)

Author

Perrier, Fanny, Bussiere, Sylvie, Coriou, Cécile, Candaudap, Frédéric, Pokrovsky, Oleg, Nguyen, Christophe, Cornu, Jean-Yves, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France

Subjects
blé dur, variétés, cadmium, répartition, dilution isotopique, [SDV.SA]Life Sciences [q-bio]/Agricultural sciences, Vegetal Biology, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, Sciences agricoles, Biologie végétale, ComputingMilieux_MISCELLANEOUS, Agricultural sciences
Abstract

National audience

Published
2014

47. Cadmium uptake and repartition over the vegetative growth in Helianthus annuus grown at Cd 2 and 20 nM

Author

Cornu, Jean-Yves, Bakoto, Rémi, Nguyen, Christophe, Interactions Sol Plante Atmosphère (UMR ISPA), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro), and International Phytotechnology Society.

Subjects
macrophyte, cuivre, biomasse racinaire, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, phytotoxicité, biomasse aquatique, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

48. Use of a Synthetic Biosensor for Neutralizing Activity-Biased Selection of Monoclonal Antibodies against Atroxlysin-I, an Hemorrhagic Metalloproteinase from Bothrops atrox Snake Venom

Author

Schneider, Francisco Santos, Nguyen, Dung Le, Castro, Karen Larissa, Cobo, Sandra, Machado de Avila, Ricardo Andrez, Ferreira, Nivia de Assis, Sanchez, Eladio Flores, Nguyen, Christophe, Granier, Claude, Galea, Pascale, Chávez-Olortegui, Carlos, Molina, Franck, Gutiérrez, José María, Sys2Diag-Modélisation et Ingénierie des Systèmes Complexes Biologiques pour le Diagnostic (Sys2Diag), Centre National de la Recherche Scientifique (CNRS)-Alcediag, UMR 9921, CNRS/UM1, Laboratoire Agronomie et Environnement (LAE), and Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)

Subjects
lcsh:Arctic medicine. Tropical medicine, lcsh:RC955-962, medicine.drug_class, [SDV]Life Sciences [q-bio], Immunology, Peptide, Venom, Biosensing Techniques, Monoclonal antibody, Biochemistry, Epitope, Immunochemistry, Fluorescence Resonance Energy Transfer, medicine, Animals, Humans, Mass Screening, Bothrops, Mass screening, ComputingMilieux_MISCELLANEOUS, chemistry.chemical_classification, biology, lcsh:Public aspects of medicine, Immunity, Public Health, Environmental and Occupational Health, Antibodies, Monoclonal, Metalloendopeptidases, Biology and Life Sciences, lcsh:RA1-1270, South America, biology.organism_classification, Antibodies, Neutralizing, Vaccination and Immunization, Molecular biology, 3. Good health, Infectious Diseases, chemistry, Snake venom, Humoral Immunity, Clinical Immunology, Antitoxins, Immunotherapy, Peptides, Snake Venoms, Research Article
Abstract

Background The snake Bothrops atrox is responsible for the majority of envenomings in the northern region of South America. Severe local effects, including hemorrhage, which are mainly caused by snake venom metalloproteinases (SVMPs), are not fully neutralized by conventional serum therapy. Little is known about the immunochemistry of the P-I SVMPs since few monoclonal antibodies (mAbs) against these molecules have been obtained. In addition, producing toxin-neutralizing mAbs remains very challenging. Methodology/Principal Findings Here, we report on the set-up of a functional screening based on a synthetic peptide used as a biosensor to select neutralizing mAbs against SVMPs and the successful production of neutralizing mAbs against Atroxlysin-I (Atr-I), a P-I SVMP from B. atrox. Hybridomas producing supernatants with inhibitory effect against the proteolytic activity of Atr-I towards the FRET peptide Abz-LVEALYQ-EDDnp were selected. Six IgG1 Mabs were obtained (named mAbatr1 to mAbatr6) and also two IgM. mAbatrs1, 2, 3 and 6 were purified. All showed a high specific reactivity, recognizing only Atr-I and B. atrox venom in ELISA and a high affinity, showing equilibrium constants in the nM range for Atr-I. These mAbatrs were not able to bind to Atr-I overlapping peptides, suggesting that they recognize conformational epitopes. Conclusions/Significance For the first time a functional screening based on a synthetic biosensor was successfully used for the selection of neutralizing mAbs against SVMPs., Author Summary In this work, we propose a new screening strategy to produce monoclonal antibodies against Atr-I, a P-I class SVMP from Bothrops atrox, which is the snake responsible for the majority of the accidents in South America. SVMPs are the main toxic factors in Bothrops venom causing systemic and local hemorrhage, which may evolve to inflammation and/or necrosis. Since the toxic effects of SVMPs are related to their proteolytic activity, we have produced a peptide which was used as a biosensor for Atr-I hydrolysis. Hydrolysis of this substrate was monitored and the clones possessing inhibitory activity against the proteolytic activity of Atr-I upon the peptide were selected. Using our new approach, we have obtained four monoclonal antibodies highly specific and with neutralizing capacity against the hemorrhagic activity of either Atr-I alone or Bothrops atrox whole venom. To the best of the authors' knowledge, this is the first time where a functional screening is used for the selection of neutralizing mAbs against SVMPs. It is also the first description of mAbs anti-Atr-I, with inhibitory potential against its toxic activities which may be useful for diagnosis and treatment in the future.

Published
2014

50. Malaria in French Guiana Linked to Illegal Gold Mining

Author

Pommier de Santi, Vincent, primary, Dia, Aissata, additional, Adde, Antoine, additional, Hyvert, Georges, additional, Galant, Julien, additional, Mazevet, Michel, additional, Nguyen, Christophe, additional, Vezenegho, Samuel B., additional, Dusfour, Isabelle, additional, Girod, Romain, additional, and Briolant, Sébastien, additional

Published
2016
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