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23 results on '"Audrey Lorthiois"'

1. Hemisynthetic alkaloids derived from trilobine are antimalarials with sustained activity in multidrug-resistant Plasmodium falciparum

Author

Flore Nardella, Irina Dobrescu, Haitham Hassan, Fabien Rodrigues, Sabine Thiberge, Liliana Mancio-Silva, Ambre Tafit, Corinne Jallet, Véronique Cadet-Daniel, Stéphane Goussin, Audrey Lorthiois, Yoann Menon, Nicolas Molinier, Dany Pechalrieu, Christophe Long, François Sautel, Mariette Matondo, Magalie Duchateau, Guillaume Médard, Benoit Witkowski, Artur Scherf, Ludovic Halby, and Paola B. Arimondo

Subjects
Multi-drug resistant organisms, Natural product chemistry, Applied microbiology, Microbiology parasite, Clinical microbiology, Science
Abstract

Summary: Malaria eradication requires the development of new drugs to combat drug-resistant parasites. We identified bisbenzylisoquinoline alkaloids isolated from Cocculus hirsutus that are active against Plasmodium falciparum blood stages. Synthesis of a library of 94 hemi-synthetic derivatives allowed to identify compound 84 that kills multi-drug resistant clinical isolates in the nanomolar range (median IC50 ranging from 35 to 88 nM). Chemical optimization led to compound 125 with significantly improved preclinical properties. 125 delays the onset of parasitemia in Plasmodium berghei infected mice and inhibits P. falciparum transmission stages in vitro (culture assays), and in vivo using membrane feeding assay in the Anopheles stephensi vector. Compound 125 also impairs P. falciparum development in sporozoite-infected hepatocytes, in the low micromolar range. Finally, by chemical pull-down strategy, we characterized the parasite interactome with trilobine derivatives, identifying protein partners belonging to metabolic pathways that are not targeted by the actual antimalarial drugs or implicated in drug-resistance mechanisms.

Published
2023
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2. The Host Protein Aquaporin-9 is Required for Efficient Plasmodium falciparum Sporozoite Entry into Human Hepatocytes

Author

Nadia Amanzougaghene, Shahin Tajeri, Samir Yalaoui, Audrey Lorthiois, Valérie Soulard, Audrey Gego, Armelle Rametti, Véronica Risco-Castillo, Alicia Moreno, Maurel Tefit, Geert-Jan van Gemert, Robert W. Sauerwein, Jean-Christophe Vaillant, Philippe Ravassard, Jean-Louis Pérignon, Patrick Froissard, Dominique Mazier, and Jean-François Franetich

Subjects
Plasmodium falciparum, sporozoites, liver stage, hepatocytes, Aquaporin-9, CD81, Microbiology, QR1-502
Abstract

Hepatocyte invasion by Plasmodium sporozoites represents a promising target for innovative antimalarial therapy, but the molecular events mediating this process are still largely uncharacterized. We previously showed that Plasmodium falciparum sporozoite entry into hepatocytes strictly requires CD81. However, CD81-overexpressing human hepatoma cells remain refractory to P. falciparum infection, suggesting the existence of additional host factors necessary for sporozoite entry. Here, through differential transcriptomic analysis of human hepatocytes and hepatoma HepG2-CD81 cells, the transmembrane protein Aquaporin-9 (AQP9) was found to be among the most downregulated genes in hepatoma cells. RNA silencing showed that sporozoite invasion of hepatocytes requires AQP9 expression. AQP9 overexpression in hepatocytes increased their permissiveness to P. falciparum. Moreover, chemical disruption with the AQP9 inhibitor phloretin markedly inhibited hepatocyte infection. Our findings identify AQP9 as a novel host factor required for P. falciparum sporozoite hepatocyte-entry and indicate that AQP9 could be a potential therapeutic target.

Published
2021
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3. Antiplasmodial activity of traditional polyherbal remedy from Odisha, India: Their potential for prophylactic use

Author

Prakash Bangalore Nagendrappa, Jean-François Franetich, Frederick Gay, Audrey Lorthiois, Padma Venkatasubramanian, and Dominique Mazier

Subjects
Polyherbal remedy, Plasmodium, Malaria prophylaxis, Antiplasmodial activity, Arctic medicine. Tropical medicine, RC955-962, Biology (General), QH301-705.5
Abstract

Objective: To evaluate the potential prophylactic activity of traditional polyherbal remedy against malaria. Methods: A traditional polyherbal remedy against malaria from Odisha, India was evaluated for its potential prophylactic activity using in vitro hepatic cell lines assay and the murine malaria system Plasmodium yoelii yoelii/Anopheles stephensi. Results: The polyherbal extract inhibited the Plasmodium yoelii hepatic stages in vitro (IC50 0.74 mg/mL), a therapeutic index of 9.54. In mice treated with the aqueous extract (2000 mg/kg/day), peak parasitaemia values were 81% lower in the experimental 2.35% ± 0.14% as compared to controls 12.62% ± 0.52% (P

Published
2015
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4. cAMP-Signalling Regulates Gametocyte-Infected Erythrocyte Deformability Required for Malaria Parasite Transmission.

Author

Ghania Ramdani, Bernina Naissant, Eloise Thompson, Florence Breil, Audrey Lorthiois, Florian Dupuy, Ross Cummings, Yoann Duffier, Yolanda Corbett, Odile Mercereau-Puijalon, Kenneth Vernick, Donatella Taramelli, David A Baker, Gordon Langsley, and Catherine Lavazec

Subjects
Immunologic diseases. Allergy, RC581-607, Biology (General), QH301-705.5
Abstract

Blocking Plasmodium falciparum transmission to mosquitoes has been designated a strategic objective in the global agenda of malaria elimination. Transmission is ensured by gametocyte-infected erythrocytes (GIE) that sequester in the bone marrow and at maturation are released into peripheral blood from where they are taken up during a mosquito blood meal. Release into the blood circulation is accompanied by an increase in GIE deformability that allows them to pass through the spleen. Here, we used a microsphere matrix to mimic splenic filtration and investigated the role of cAMP-signalling in regulating GIE deformability. We demonstrated that mature GIE deformability is dependent on reduced cAMP-signalling and on increased phosphodiesterase expression in stage V gametocytes, and that parasite cAMP-dependent kinase activity contributes to the stiffness of immature gametocytes. Importantly, pharmacological agents that raise cAMP levels in transmissible stage V gametocytes render them less deformable and hence less likely to circulate through the spleen. Therefore, phosphodiesterase inhibitors that raise cAMP levels in P. falciparum infected erythrocytes, such as sildenafil, represent new candidate drugs to block transmission of malaria parasites.

Published
2015
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5. A genetically attenuated malaria vaccine candidate based on P. falciparum b9/slarp gene-deficient sporozoites

Author

Ben C L van Schaijk, Ivo H J Ploemen, Takeshi Annoura, Martijn W Vos, Lander Foquet, Geert-Jan van Gemert, Severine Chevalley-Maurel, Marga van de Vegte-Bolmer, Mohammed Sajid, Jean-Francois Franetich, Audrey Lorthiois, Geert Leroux-Roels, Philip Meuleman, Cornelius C Hermsen, Dominique Mazier, Stephen L Hoffman, Chris J Janse, Shahid M Khan, and Robert W Sauerwein

Subjects
Plasmodium, sporozoite, genetically attenuated parasite, malaria, vaccine, Medicine, Science, Biology (General), QH301-705.5
Abstract

A highly efficacious pre-erythrocytic stage vaccine would be an important tool for the control and elimination of malaria but is currently unavailable. High-level protection in humans can be achieved by experimental immunization with Plasmodium falciparum sporozoites attenuated by radiation or under anti-malarial drug coverage. Immunization with genetically attenuated parasites (GAP) would be an attractive alternative approach. In this study, we present data on safety and protective efficacy using sporozoites with deletions of two genes, that is the newly identified b9 and slarp, which govern independent and critical processes for successful liver-stage development. In the rodent malaria model, PbΔb9ΔslarpGAP was completely attenuated showing no breakthrough infections while efficiently inducing high-level protection. The human PfΔb9ΔslarpGAP generated without drug resistance markers were infective to human hepatocytes in vitro and to humanized mice engrafted with human hepatocytes in vivo but completely aborted development after infection. These findings support the clinical development of a PfΔb9ΔslarpSPZ vaccine.

Published
2014
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6. P. falciparum isolate-specific distinct patterns of induced apoptosis in pulmonary and brain endothelial cells.

Author

Nadine N'Dilimabaka, Zacharie Taoufiq, Sergine Zougbédé, Serge Bonnefoy, Audrey Lorthiois, Pierre Oliver Couraud, Angelita Rebollo, Georges Snounou, Dominique Mazier, and Alicia Moreno Sabater

Subjects
Medicine, Science
Abstract

The factors implicated in the transition from uncomplicated to severe clinical malaria such as pulmonary oedema and cerebral malaria remain unclear. It is known that alterations in vascular integrity due to endothelial cell (EC) activation and death occur during severe malaria. In this study, we assessed the ability of different P. falciparum clinical isolates to induce apoptosis in ECs derived from human lung and brain. We observed that induction of EC apoptosis was sensitive to the environmental pH and required direct contact between the parasite and the cell, though it was not correlated to the ability of the parasite to cytoadhere. Moreover, the extent of induced apoptosis in the two EC types varied with the isolate. Analysis of parasite genes transcript led us to propose that the activation of different pathways, such as Plasmodium apoptosis-linked pathogenicity factors (PALPF), PALPF-2, PALPF-5 and PF11_0521, could be implied in EC death. These observations provide an experimental framework to decipher the molecular mechanism implicated in the genesis of severe malaria.

Published
2014
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7. Hemisynthetic derivatives of the natural alkaloid trilobine are fast-acting antimalarial compounds with sustained activity in multi-drug resistant P. falciparum isolates

Author

Flore Nardella, Irina Dobrescu, Haitham Hassan, Fabien Rodrigues, Sabine Thiberge, Liliana Mancio Silva, Ambre Tafit, Corinne Jallet, Véronique Cadet-Daniel, Stéphane Goussin, Audrey Lorthiois, Yoann Menon, Nicolas Molinier, Dany Pechalrieu, Christophe Long, François Sautel, Mariette Matondo, Magalie Duchateau, Guillaume Medard, Benoit Witkowski, Artur Scherf, Ludovic Halby, and Paola B. Arimondo

Abstract

Malaria eradication requires the development of new drugs to combat drug-resistant parasites. The search for new chemical scaffolds that target novel pathways of the human malaria parasite Plasmodium falciparum is of highest priority. We identified bisbenzylisoquinoline alkaloids isolated from Cocculus hirsutus. (trilobine derivatives) as active in the nanomolar range against P. falciparum blood stages. Synthesis of a library of 94 hemi-synthetic derivatives allowed us to identify compound 84 that kills multi-drug resistant clinical isolates in the nanomolar range (median IC50 ranging from 35-88nM). Efforts were made to obtain compounds with significantly improved preclinical properties. Out of those, compound 125 delays the onset of parasitemia in P. berghei infected mice and inhibits P. falciparum transmission stages in vitro (culture assays) and in vivo using membrane feeding assay in the Anopheles stephensi vector. Compound 125 also impairs P. falciparum development in sporozoite-infected hepatocytes, in the low micromolar range. Finally, we used a chemical pull-down strategy to identify potential protein targets of this chemical family. Mass spectrometry analysis identified the parasite interactome with trilobine derivatives, identifying protein partners belonging to metabolic pathways that have not been previously targeted by antimalarial drugs or implicated in drug-resistance mechanisms.

Published
2022

8. Plasmodium falciparum sexual parasites develop in human erythroblasts and affect erythropoiesis

Author

Nabih Azar, Rafael M Martins, Prativa Kumari Behera, Audrey Lorthiois, Amanda K. A. Silva, Jose-Juan Lopez-Rubio, Gaelle Neveu, Pradeep Annamalai Subramani, Florence Gazeau, Catherine Lavazec, Dominique Mazier, Benjamin Marcel-Zerrougui, Samuel C. Wassmer, Sanghamitra Satpathi, Cyrielle Richard, Patrice Vallin, Aruna Mukti Minz, Frédérique Verdier, Muriel Andrieu, Florian Dupuy, Fiona Volpe, Institut Cochin (IC UM3 (UMR 8104 / U1016)), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), ispat general hospital [Rourkela, India] (IGH), Centre d'Immunologie et de Maladies Infectieuses (CIMI), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Service d'Hématologie Biologique [CHU Pitié-Salpêtrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université, CNRS UMR 7057 - Laboratoire Matières et Systèmes Complexes (MSC) (MSC), Centre National de la Recherche Scientifique (CNRS), LPHI - Laboratory of Pathogen Host Interactions (LPHI), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), Institut Pasteur [Paris], Matière et Systèmes Complexes (MSC (UMR_7057)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Hi-Tech Medical College [Rourkela, India], Institut National de la Santé et de la Recherche Médicale (INSERM), London School of Hygiene and Tropical Medicine (LSHTM), This work was supported by Cnrs, Inserm, the French Ministère de l’Enseignement Supérieur et de la Recherche and the Laboratory of Excellence GR-Ex, reference ANR-11-LABX-0051, funded by the IdEx program 'Investissements d’avenir' of the French National Research Agency, reference ANR-18-IDEX0001 (to GN, CL and FV). This study was also funded by the Fondation pour la Recherche Médicale under award number 'Equipe FRM' EQ20170336722 (to CL), the National Institute of Allergy and Infectious Diseases of the National Institutes of Health under award number U19AI089676 (to SCW), and the UK Medical Research Council under award number MR/S009450/1 (to SCW). This work was partly supported by the French Parasitology consortium grant ParaFrap (ANR‐11‐LABX0024) to DM and PAS was supported by an ANR grant 'HypEpicC' to DM., The authors acknowledge the CYBIO Flow Cytometry core facility, the IMAG’IC imaging core facility and the Electron microscopy core facility of the Institut Cochin for technical help. The Electron Microscopy work was also carried out at ICM-QUANT Bioimaging core facility, ICM-Hospital Pitié Salpêtrière, Paris. We are grateful to Odile Mercereau-Puijalon and Micheline Guillotte for providing the anti-Pf11-1 antibodies and the VarO parasite line. We thank Jayamalini Jeremias for technical support. We thank Naomi Taylor, Silvia Portugal, Laurent Renia, Bjorn Kafsack, Robert Ménard and Frédéric Ariey for fruitful discussions., ANR-11-IDEX-0005-02/11-LABX-0051,GR-Ex,Biogenèse et pathologies du globule rouge(2011), ANR: 11-LABX-0024,ParaFrap,Alliance française contre les maladies parasitaires(2011), ANR-14-CE16-0013,HypEpiC,Développement d'une nouvelle stratégie 'wake and kill' pour une cure radicale basée sur le contrôle épigénétique de la quiescence des hypnozoïtes de Plasmodium(2014), Université de Paris (UP), Lorthiois, Audrey, Université Sorbonne Paris Cité - - USPC2011 - ANR-11-IDEX-0005 - IDEX - VALID, Laboratoires d'excellence - Alliance française contre les maladies parasitaires - - ParaFrap2011 - ANR-11-LABX-0024 - LABX - VALID, Appel à projets générique - Développement d'une nouvelle stratégie 'wake and kill' pour une cure radicale basée sur le contrôle épigénétique de la quiescence des hypnozoïtes de Plasmodium - - HypEpiC2014 - ANR-14-CE16-0013 - Appel à projets générique - VALID, Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre d'Immunologie et des Maladies Infectieuses (CIMI), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), ANR-11-IDEX-0005,USPC,Université Sorbonne Paris Cité(2011), ANR-11-LABX-0024,ParaFrap,Alliance française contre les maladies parasitaires(2011), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)

Subjects
0301 basic medicine, Adult, [SDV.MHEP.HEM] Life Sciences [q-bio]/Human health and pathology/Hematology, Erythroblasts, Iron, [SDV]Life Sciences [q-bio], Immunology, Plasmodium falciparum, Red Cells, Biochemistry, Plasmodium, Host-Parasite Interactions, 03 medical and health sciences, Young Adult, 0302 clinical medicine, Nucleated cell, Bone Marrow, parasitic diseases, medicine, Gametocyte, Humans, Erythropoiesis, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Malaria, Falciparum, Cells, Cultured, ComputingMilieux_MISCELLANEOUS, biology, [SDV.MHEP.HEM]Life Sciences [q-bio]/Human health and pathology/Hematology, Cell Biology, Hematology, medicine.disease, biology.organism_classification, 3. Good health, Cell biology, [SDV] Life Sciences [q-bio], Haematopoiesis, 030104 developmental biology, medicine.anatomical_structure, 030220 oncology & carcinogenesis, Female, Bone marrow, Malaria, [SDV.MP.PAR] Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology
Abstract

Plasmodium falciparum gametocytes, the sexual stage responsible for malaria parasite transmission from humans to mosquitoes, are key targets for malaria elimination. Immature gametocytes develop in the human bone marrow parenchyma, where they accumulate around erythroblastic islands. Notably though, the interactions between gametocytes and this hematopoietic niche have not been investigated. Here, we identify late erythroblasts as a new host cell for P falciparum sexual stages and show that gametocytes can fully develop inside these nucleated cells in vitro and in vivo, leading to infectious mature gametocytes within reticulocytes. Strikingly, we found that infection of erythroblasts by gametocytes and parasite-derived extracellular vesicles delay erythroid differentiation, thereby allowing gametocyte maturation to coincide with the release of their host cell from the bone marrow. Taken together, our findings highlight new mechanisms that are pivotal for the maintenance of immature gametocytes in the bone marrow and provide further insights on how Plasmodium parasites interfere with erythropoiesis and contribute to anemia in malaria patients.

Published
2020

9. Role of a patatin-like phospholipase in Plasmodium falciparum gametogenesis and malaria transmission

Author

Aditi Alaganan, Chetan E. Chitnis, Lhousseine Touqui, Julien Guglielmini, Kunal R. More, Micheline Guillotte Blisnick, Sabine Thiberge, Shailja Singh, Audrey Lorthiois, Olivier Gorgette, Pallavi Singh, Shivani Shankar Aguilera, Biologie de Plasmodium et Vaccins - Malaria Parasite Biology and Vaccines, Institut Pasteur [Paris], ED 515 - Complexité du vivant, Sorbonne Université (SU), Centre de Production et Infection des Anophèles (plateforme) - Center for the Production and Infection of Anopheles (platform) (CEPIA), Plateforme BioImagerie Ultrastructurale – Ultrastructural BioImaging Platform (UTechS UBI), Hub Bioinformatique et Biostatistique - Bioinformatics and Biostatistics HUB, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Mucoviscidose et bronchopathies chroniques : biopathologie et phénotype cliniques - Cystic Fibrosis and Bronchial Diseases, CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Pasteur [Paris], Service de Pédiatrie et Réanimations néonatales [Béclère], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-AP-HP - Hôpital Antoine Béclère [Clamart], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Jawaharlal Nehru University (JNU), This work was supported by a grant from Agence Nationale de la Recherche (ANR-17-CE15-0010) (C.E.C.) and internal funds from Institut Pasteur (C.E.C.). P.S. was a student of the Pasteur Paris Universities International Doctoral Program and was supported by a fellowship from Chronopost. P.S. was also supported by an Institut Carnot postdoctoral fellowship. A.A. was supported by a European Molecular Biology Organization (EMBO) postdoctoral fellowship., We thank Catherine Lavazec, Institut Cochin, Paris, for providing us P. falciparum NF54 strain and helping us initiate work on gametocytes. We thank Ellen Knuepfer and Tony Holder, Francis Crick Institute, London, for providing the CRISPR-Cas9 plasmids and Marta Tiburcio and Moritz Treeck, Francis Crick Institute, London, for providing the P. falciparum NF54 DiCre line. We also thank Jacomine Krijnse-Locker, of the electron microscopy Ultrastructural Bioimaging (UBI) platform, Insitut Pasteur, Paris, for providing ready access to the electron microscopy facility and Pietro Alano, Istituto Superiore di Sanita, Rome, for rabbit antisera against Pfg377., ANR-17-CE15-0010,MolSigMal,Evènements moléculaires de la signalisation induite par l'invasion des globules rouges par les parasites paludéens(2017), Institut Pasteur [Paris] (IP), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Lorthiois, Audrey, and Evènements moléculaires de la signalisation induite par l'invasion des globules rouges par les parasites paludéens - - MolSigMal2017 - ANR-17-CE15-0010 - AAPG2017 - VALID

Subjects
MESH: Plasmodium falciparum / physiology, MESH: Malaria, Falciparum / parasitology, [SDV]Life Sciences [q-bio], malaria, MESH: Protozoan Proteins / genetics, Phospholipase, MESH: Gametogenesis, MESH: Malaria, Falciparum / transmission, MESH: Phospholipases / genetics, 03 medical and health sciences, MESH: Protozoan Proteins / metabolism, parasitic diseases, medicine, Gametocyte, Secretion, malaria transmission, MESH: Life Cycle Stages, Gametogenesis, Plasmodium gametogenesis, 030304 developmental biology, 0303 health sciences, Multidisciplinary, MESH: Humans, biology, MESH: Computational Biology / methods, 030302 biochemistry & molecular biology, Anopheles, Plasmodium falciparum, MESH: Sequence Deletion, biology.organism_classification, 3. Good health, Cell biology, [SDV] Life Sciences [q-bio], patatin-like phospholipases, medicine.anatomical_structure, MESH: Plasmodium falciparum / ultrastructure, Patatin-like phospholipase, Gamete, MESH: Phospholipases / metabolism
Abstract

International audience; Transmission of Plasmodium falciparum involves a complex process that starts with the ingestion of gametocytes by female Anopheles mosquitoes during a blood meal. Activation of gametocytes in the mosquito midgut triggers "rounding up" followed by egress of both male and female gametes. Egress requires secretion of a perforin-like protein, PfPLP2, from intracellular vesicles to the periphery, which leads to destabilization of peripheral membranes. Male gametes also develop flagella, which assist in binding female gametes for fertilization. This process of gametogenesis, which is key to malaria transmission, involves extensive membrane remodeling as well as vesicular discharge. Phospholipase A2 enzymes (PLA2) are known to mediate membrane remodeling and vesicle secretion in diverse organisms. Here, we show that a P. falciparum patatin-like phospholipase (PfPATPL1) with PLA2 activity plays a key role in gametogenesis. Conditional deletion of the gene encoding PfPATPL1 does not affect P. falciparum blood stage growth or gametocyte development but reduces efficiency of rounding up, egress, and exflagellation of gametocytes following activation. Interestingly, deletion of the PfPATPL1 gene inhibits secretion of PfPLP2, reducing the efficiency of gamete egress. Deletion of PfPATPL1 also reduces the efficiency of oocyst formation in mosquitoes. These studies demonstrate that PfPATPL1 plays a role in gametogenesis, thereby identifying PLA2 phospholipases such as PfPATPL1 as potential targets for the development of drugs to block malaria transmission.

Published
2019

10. Role of a patatin-like phospholipase in

Author

Pallavi, Singh, Aditi, Alaganan, Kunal R, More, Audrey, Lorthiois, Sabine, Thiberge, Olivier, Gorgette, Micheline, Guillotte Blisnick, Julien, Guglielmini, Shivani Shankar, Aguilera, Lhousseine, Touqui, Shailja, Singh, and Chetan E, Chitnis

Subjects
Life Cycle Stages, PNAS Plus, Phospholipases, parasitic diseases, Plasmodium falciparum, Protozoan Proteins, Computational Biology, Humans, Malaria, Falciparum, Gametogenesis, Sequence Deletion
Abstract

Transmission of Plasmodium falciparum involves a complex process that starts with the ingestion of gametocytes by female Anopheles mosquitoes during a blood meal. Activation of gametocytes in the mosquito midgut triggers “rounding up” followed by egress of both male and female gametes. Egress requires secretion of a perforin-like protein, PfPLP2, from intracellular vesicles to the periphery, which leads to destabilization of peripheral membranes. Male gametes also develop flagella, which assist in binding female gametes for fertilization. This process of gametogenesis, which is key to malaria transmission, involves extensive membrane remodeling as well as vesicular discharge. Phospholipase A2 enzymes (PLA2) are known to mediate membrane remodeling and vesicle secretion in diverse organisms. Here, we show that a P. falciparum patatin-like phospholipase (PfPATPL1) with PLA2 activity plays a key role in gametogenesis. Conditional deletion of the gene encoding PfPATPL1 does not affect P. falciparum blood stage growth or gametocyte development but reduces efficiency of rounding up, egress, and exflagellation of gametocytes following activation. Interestingly, deletion of the PfPATPL1 gene inhibits secretion of PfPLP2, reducing the efficiency of gamete egress. Deletion of PfPATPL1 also reduces the efficiency of oocyst formation in mosquitoes. These studies demonstrate that PfPATPL1 plays a role in gametogenesis, thereby identifying PLA2 phospholipases such as PfPATPL1 as potential targets for the development of drugs to block malaria transmission.

Published
2019

11. Plasmodium falciparum STEVOR phosphorylation regulates host erythrocyte deformability enabling malaria parasite transmission

Author

Judith A. M. Scholz, Catherine Lavazec, Julien Duez, Florian Dupuy, Pierre Buffet, Bernina Naissant, Audrey Lorthiois, Yoann Duffier, Anna Bachmann, and Anais Merckx

Subjects
0301 basic medicine, Immunoprecipitation, Plasmodium falciparum, 030106 microbiology, Immunology, Protozoan Proteins, Antigens, Protozoan, Biochemistry, Host-Parasite Interactions, 03 medical and health sciences, Erythrocyte Deformability, Animals, Humans, Erythrocyte deformability, Ankyrin, Malaria, Falciparum, Phosphorylation, Protein kinase A, Cells, Cultured, chemistry.chemical_classification, biology, Phosphodiesterase, Cell Biology, Hematology, biology.organism_classification, Cyclic AMP-Dependent Protein Kinases, Cell biology, Open reading frame, 030104 developmental biology, chemistry
Abstract

Deformability of Plasmodium falciparum gametocyte-infected erythrocytes (GIEs) allows them to persist for several days in blood circulation and to ensure transmission to mosquitoes. Here, we investigate the mechanism by which the parasite proteins STEVOR (SubTElomeric Variable Open Reading frame) exert changes on GIE deformability. Using the microsphiltration method, immunoprecipitation, and mass spectrometry, we produce evidence that GIE stiffness is dependent on the cytoplasmic domain of STEVOR that interacts with ankyrin complex at the erythrocyte skeleton. Moreover, we show that GIE deformability is regulated by protein kinase A (PKA)–mediated phosphorylation of the STEVOR C-terminal domain at a specific serine residue (S324). Finally, we show that the increase of GIE stiffness induced by sildenafil (Viagra) is dependent on STEVOR phosphorylation status and on another independent mechanism. These data provide new insights into mechanisms by which phosphodiesterase inhibitors may block malaria parasite transmission.

Published
2016

12. De Novo Genome Assembly of a Plasmodium falciparum NF54 Clone Using Single-Molecule Real-Time Sequencing

Author

Jessica M. Bryant, Artur Scherf, Sebastian Baumgarten, Audrey Lorthiois, Christine Scheidig-Benatar, Aurélie Claes, Biologie des Interactions Hôte-Parasite - Biology of Host-Parasite Interactions, Institut Pasteur [Paris]-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut Cochin (IC UM3 (UMR 8104 / U1016)), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Biologie des Interactions Hôte-Parasite, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Gènes et pression artérielle (Inserm U772), Collège de France (CdF)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Pasteur [Paris] (IP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Gènes et pression artérielle (INSERM U772), Collège de France (CdF (institution))-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), and Centre National de la Recherche Scientifique (CNRS)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)

Subjects
0301 basic medicine, Eukaryotes, [SDV]Life Sciences [q-bio], 030106 microbiology, Clone (cell biology), Sequence assembly, Plasmodium falciparum, Computational biology, Biology, medicine.disease, biology.organism_classification, Genome, 3. Good health, 03 medical and health sciences, 030104 developmental biology, parasitic diseases, Genetics, medicine, Parasite hosting, Molecular Biology, ComputingMilieux_MISCELLANEOUS, Malaria, Single molecule real time sequencing, Sequence (medicine)
Abstract

Plasmodium falciparum is the species of human malaria parasite that causes the most severe form of the disease. Here, we used single-molecule real-time (SMRT) sequencing technology from Pacific Biosciences (PacBio) to sequence, assemble de novo , and annotate the genome of a P. falciparum NF54 clone.

Published
2018

13. Infectivity of Plasmodium falciparum sporozoites determines emerging parasitemia in infected volunteers

Author

Matthew B. B. McCall, Marga van de Vegte, Sandra Chishimba, Robert W. Sauerwein, Jean-François Franetich, Dominique Mazier, Else M. Bijker, Linda J. Wammes, Max Gerdsen, Jaap J. van Hellemond, Jona Walk, Cornelus C. Hermsen, Perry J.J. van Genderen, Audrey Lorthiois, Marijke C. C. Langenberg, Rob Koelewijn, Geert-Jan van Gemert, Wouter Graumans, and Medical Microbiology & Infectious Diseases

Subjects
0301 basic medicine, Infectivity, biology, 030231 tropical medicine, lnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4], Heterologous, Plasmodium falciparum, General Medicine, Parasitemia, biology.organism_classification, medicine.disease, Virology, In vitro, 03 medical and health sciences, 030104 developmental biology, 0302 clinical medicine, In vivo, parasitic diseases, medicine, Parasite hosting, Malaria
Abstract

Contains fulltext : 177607.pdf (Publisher’s version ) (Closed access) Malaria sporozoites must first undergo intrahepatic development before a pathogenic blood-stage infection is established. The success of infection depends on host and parasite factors. In healthy human volunteers undergoing controlled human malaria infection (CHMI), we directly compared three clinical Plasmodium falciparum isolates for their ability to infect primary human hepatocytes in vitro and to drive the production of blood-stage parasites in vivo. Our data show a correlation between the efficiency of strain-specific sporozoite invasion of human hepatocytes and the dynamics of patent parasitemia in study subjects, highlighting intrinsic differences in infectivity among P. falciparum isolates from distinct geographical locales. The observed heterogeneity in infectivity among strains underscores the value of assessing the protective efficacy of candidate malaria vaccines against heterologous strains in the CHMI model.

Published
2017

14. A humanized mouse model for sequestration of Plasmodium falciparum sexual stages and in vivo evaluation of gametocytidal drugs OPEN

Author

Florian Dupuy, Yoann Duffier, Catherine Lavazec, Dominique Mazier, Audrey Lorthiois, Grégory Jouvion, Laurence Fiette, Pau Cisteró, Alfredo Mayor, Alicia Moreno Sabater, Institut Cochin, Université Paris Descartes - Paris 5 (UPD5) - Université Sorbonne Paris Cité (USPC) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Centre National de la Recherche Scientifique (CNRS), Barcelona Centre for International Health Research, Hospital Clinic (CRESIB), Universitat de Barcelona, Histopathologie humaine et Modèles animaux, Institut Pasteur [Paris], Centre d'Immunologie et de Maladies Infectieuses (CIMI), Université Pierre et Marie Curie - Paris 6 (UPMC) - Institut National de la Santé et de la Recherche Médicale (INSERM) - Centre National de la Recherche Scientifique (CNRS), Service de parasitologie - mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) - CHU Pitié-Salpêtrière [APHP], Génétique et Génomique des Insectes vecteurs, Institut Pasteur [Paris] - Centre National de la Recherche Scientifique (CNRS), CHU Saint-Antoine [APHP], Financial support from the Fonds Inkermann and the Cnrs (ATIP-Avenir grant), Institut Cochin (IC UM3 (UMR 8104 / U1016)), Centre National de la Recherche Scientifique (CNRS)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM), GR-Ex, Laboratoire d'Excellence, GR-Ex, Universitat de Barcelona (UB), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Service de Parasitologie - Mycologie [CHU Saint-Antoine], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Saint-Antoine [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Sorbonne Université (SU), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Institut Pasteur [Paris] (IP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), CHU Saint-Antoine [AP-HP], Institut Cochin ( UM3 (UMR 8104 / U1016) ), Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Barcelona Centre for International Health Research, Hospital Clinic ( CRESIB ), Universitat de Barcelona ( UB ), Centre d'Immunologie et de Maladies Infectieuses ( CIMI ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Pitié-Salpêtrière [APHP], Institut Pasteur [Paris]-Centre National de la Recherche Scientifique ( CNRS ), Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Saint-Antoine [APHP], HAL-UPMC, Gestionnaire, Service de Parasitologie - Mycologie [CHU Pitié-Salpétrière], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)

Subjects
0301 basic medicine, [ SDV.MP.PAR ] Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Erythrocytes, Primaquine, Plasmodium falciparum, Malària, Article, Antimalarials, Mice, 03 medical and health sciences, Bone Marrow, In vivo, parasitic diseases, medicine, Gametocyte, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, Animals, Humans, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Malaria, Falciparum, Life Cycle Stages, Multidisciplinary, biology, In vitro toxicology, [SDV.SP]Life Sciences [q-bio]/Pharmaceutical sciences, biology.organism_classification, medicine.disease, Virology, 3. Good health, Malaria, [SDV.SP] Life Sciences [q-bio]/Pharmaceutical sciences, Disease Models, Animal, 030104 developmental biology, medicine.anatomical_structure, [ SDV.SP ] Life Sciences [q-bio]/Pharmaceutical sciences, Humanized mouse, Immunology, Bone marrow, [SDV.MP.PAR] Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Injections, Intraperitoneal, Spleen, medicine.drug
Abstract

International audience; The development of new drugs to disrupt malaria transmission requires the establishment of an in vivo model to address the biology of Plasmodium falciparum sexual stages (gametocytes). Herein we show that chemically immune-modulated NSG mice grafted with human erythrocytes support complete sexual development of P. falciparum parasites and generate high gametocytemia. Immunohistochemistry and RT-qPCR analyses indicate an enrichment of immature gametocytes in the bone marrow and the spleen, suggesting a sequestration mechanism reminiscent to that observed in humans. Upon primaquine treatment, elimination of gametocytes from peripheral blood and from sequestration sites was observed, providing a proof of concept that these mice can be used for testing drugs. Therefore, this model allows the investigation of P. falciparum sexual commitment, gametocyte interactions with the bone marrow and spleen and provides the missing link between current in vitro assays and Phase I trials in humans for testing new malaria gametocytidal drugs. The eradication of malaria requires the development of new transmission-blocking drugs that have to be tested in animal models 1. Plasmodium falciparum transmission from humans to mosquitoes is ensured by the parasite sexual stages called gametocytes. Immature gametocytes, from stage I to IV, develop in erythrocytes that seques-ter approximately 10 days in internal organs. Only the mature stages (stage V) are found in the peripheral blood where they are available for ingestion by mosquitoes. Recent molecular and histological studies of post-mortem specimens and clinical studies from infected individuals revealed that immature gametocytes are present in the extravascular compartment of the human bone marrow 2–4. In addition, early post-mortem observations and a recent clinical case report on a splenectomized patient suggested that immature gametocytes might also sequester in the spleen 5–7. However, it is still unclear whether the spleen is a site for maturation or clearance of immature gametocytes. The molecular mechanisms underlying the sequestration of gametocytes, followed by their release upon maturation into the circulation, remains one of the unanswered questions in the biology of malaria parasites that needs to be addressed by in vivo studies 8. One of the major challenges in studying P. falciparum gametocytes in laboratory animals is the parasite's specificity for its human host and the important biological differences that exist between P. falciparum and rodent malaria gametocytes. Moreover, the use of non-human primates is limited due to economic and ethical considerations. In addition, P. falciparum infection with a gametocyte-producing parasite strain can only be achieved in

Published
2016

15. Infectivity of

Author

Matthew B B, McCall, Linda J, Wammes, Marijke C C, Langenberg, Geert-Jan, van Gemert, Jona, Walk, Cornelus C, Hermsen, Wouter, Graumans, Rob, Koelewijn, Jean-François, Franetich, Sandra, Chishimba, Max, Gerdsen, Audrey, Lorthiois, Marga, van de Vegte, Dominique, Mazier, Else M, Bijker, Jaap J, van Hellemond, Perry J J, van Genderen, and Robert W, Sauerwein

Subjects
Volunteers, Sporozoites, Plasmodium falciparum, Hepatocytes, Humans, Female, Malaria, Falciparum, Parasitemia, Retrospective Studies
Abstract

Malaria sporozoites must first undergo intrahepatic development before a pathogenic blood-stage infection is established. The success of infection depends on host and parasite factors. In healthy human volunteers undergoing controlled human malaria infection (CHMI), we directly compared three clinical

Published
2016

16. Plasmodium falciparum full life cycle and Plasmodium ovale liver stages in humanized mice

Author

Jean François Franetich, Marc Thellier, Frédérique Capron, Georges Snounou, Maurel Tefit, Mallaury Bordessoulles, Gilles Le Naour, Alicia Moreno-Sabater, Gigliola Zanghi, Clémentine Roucher, Serban Morosan, Valérie Soulard, Henriette Bosson-Vanga, Audrey Lorthiois, Hiroshi Suemizu, Dominique Mazier, Centre d'Immunologie et de Maladies Infectieuses (CIMI), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), Departement de Parasitologie-Mycologie, Université Félix Houphouët-Boigny (UFHB), Service de parasitologie - mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), UMS28, Université Pierre et Marie Curie - Paris 6 (UPMC), Service d'Anatomie et cytologie pathologiques [CHU Pitié-Salpêtrière] (ACP), Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Central Institute for Experimental Animal, MaTuRe Project funded by the French National Agency for research (ANR), Fondation pour la Recherche Médicale (grant DPM20121125558), MultiMalVax project (Grant Agreement number: 305282), PathCo project (Grant Agreement HEALTH-F3-2012-305578), PARAFRAP LabEx of the French Parasitology Alliance For Health Care, DIM Malinf grant from the Ile-de-France region, ANR-10-BLAN-0726,MaTuRe,Mécanismes d'action et cibles de nouvelles molécules antipaludiques(2010), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Phénotypage du petit animal (UMS28), Bos, Mireille, BLANC - Mécanismes d'action et cibles de nouvelles molécules antipaludiques - - MaTuRe2010 - ANR-10-BLAN-0726 - BLANC - VALID, Service de Parasitologie - Mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), and Service d'Anatomie et cytologie pathologiques = Service de Pathologie [CHU Pitié-Salpêtrière] (ACP)

Subjects
Male, Period (gene), 030231 tropical medicine, Plasmodium falciparum, Plasmodium ovale, General Physics and Astronomy, Mice, Transgenic, Biology, Plasmodium, General Biochemistry, Genetics and Molecular Biology, Article, 03 medical and health sciences, 0302 clinical medicine, In vivo, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, medicine, Gametocyte, Animals, Humans, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, 030304 developmental biology, 0303 health sciences, Life Cycle Stages, Multidisciplinary, Transition (genetics), General Chemistry, medicine.disease, biology.organism_classification, Virology, 3. Good health, Malaria, Disease Models, Animal, Liver, Sporozoites, Hepatocytes, Female, Erythrocyte Transfusion
Abstract

Experimental studies of Plasmodium parasites that infect humans are restricted by their host specificity. Humanized mice offer a means to overcome this and further provide the opportunity to observe the parasites in vivo. Here we improve on previous protocols to achieve efficient double engraftment of TK-NOG mice by human primary hepatocytes and red blood cells. Thus, we obtain the complete hepatic development of P. falciparum, the transition to the erythrocytic stages, their subsequent multiplication, and the appearance of mature gametocytes over an extended period of observation. Furthermore, using sporozoites derived from two P. ovale-infected patients, we show that human hepatocytes engrafted in TK-NOG mice sustain maturation of the liver stages, and the presence of late-developing schizonts indicate the eventual activation of quiescent parasites. Thus, TK-NOG mice are highly suited for in vivo observations on the Plasmodium species of humans., Mice engrafted with human cells are useful models for research on human malaria parasites. Here the authors show that the complete life cycle of Plasmodium falciparum and the liver stages of Plasmodium ovale can be studied in mice doubly engrafted with human primary hepatocytes and red blood cells.

Published
2015

17. Discovery of new thienopyrimidinone derivatives displaying antimalarial properties toward both erythrocytic and hepatic stages of Plasmodium

Author

Audrey Lorthiois, Sylvain Rault, Anita Cohen, Pascal Rathelot, Carol Hopkins Sibley, Lucie Paloque, Maxime D. Crozet, Aurélien Lesnard, Pierre Verhaeghe, Peggy Suzanne, Eric Deharo, Nadine Azas, Patrice Vanelle, Louise Basmaciyan, Jean-Charles Lancelot, Patrick Dallemagne, Sébastien Hutter, Aurélien Dumètre, Michèle Laget, Dominique Mazier, Alexis Valentin, Infections Parasitaires : Transmission, Physiopathologie et Thérapeutiques (IP-TPT), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Service de Santé des Armées, Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Laboratoire de chimie de coordination (LCC), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-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-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Pharmacochimie et Biologie pour le Développement (PHARMA-DEV), Institut de Recherche pour le Développement (IRD)-Institut de Chimie de Toulouse (ICT-FR 2599), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut de Chimie Radicalaire (ICR), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre d'Immunologie et de Maladies Infectieuses (CIMI), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Pierre et Marie Curie - Paris 6 (UPMC), WorldWide Antimalarial Resistance Network (WWARN), Université de Washington Seattle, Department of Genome Sciences [Seattle] (GS), University of Washington [Seattle], Service de parasitologie - mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Normandie Université (NU), Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut de Chimie de Toulouse (ICT), Université de Toulouse (UT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), CHU Pitié-Salpêtrière [AP-HP], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)

Subjects
Male, Activity against Plasmodium liver stages, Erythrocytes, In vitro antiplasmodial profile, Parasitemia, Pharmacology, 01 natural sciences, Mice, Chloroquine, Cricetinae, Drug Discovery, Antiplasmodial mechanism of action, 0303 health sciences, biology, Chemistry, antiplasmodial profile, Hep G2 Cells, General Medicine, 3. Good health, Liver, Biochemistry, Thieno[3,2-dlpyrimidin-4(3H)-one, Plasmodium yoelii, medicine.drug, Plasmodium falciparum, CHO Cells, Antimalarials, Structure-Activity Relationship, 03 medical and health sciences, Cricetulus, In vitro, In vivo, parasitic diseases, medicine, Animals, Humans, [CHIM]Chemical Sciences, Trophozoites, IC50, Cell Proliferation, 030304 developmental biology, 2-d]pyrimidin-4(3H)-one, 010405 organic chemistry, Organic Chemistry, biology.organism_classification, medicine.disease, Malaria, 0104 chemical sciences, Pyrimidines, Specific activity, Pharmacomodulation, Thieno[3, Genotoxicity
Abstract

International audience; A preliminary in vitro screening of compounds belonging to various chemical families from our library revealed the thieno[3,2-d]pyrimidin-4(3H)-one scaffold displayed a promising profile against Plasmodium falciparum. Then, 120 new derivatives were synthesized and evaluated in vitro; compared to drug references, 40 showed good activity toward chloroquine sensitive (IC50 35-344 nM) and resistant (IC50 45-800 nM) P. falciparum strains. They were neither cytotoxic (CC50 15-50 mu M) toward HepG2 and CHO cells, nor mutagenic. Structure activity relationships were defined. The lead-compound also appeared active against the Plasmodium liver stages (Plasmodium yoelii IC50 = 35 nM) and a preliminary in vivo evaluation indicated the in vitro activity was preserved (45% reduction in parasitemia compared to untreated infected mice). A mechanistic study demonstrated these molecules do not involve any of the pathways described for commercial drugs and exert a specific activity on the ring and trophozoite stages. 2015 Elsevier Masson SAS. All rights reserved.

Published
2015

18. A genetically attenuated malaria vaccine candidate based on P. falciparum b9/slarp gene-deficient sporozoites

Author

Shahid M. Khan, Mohammed Sajid, Severine Chevalley-Maurel, Chris J. Janse, Ben C. L. van Schaijk, Robert W. Sauerwein, Stephen L. Hoffman, Ivo H J Ploemen, Jean-François Franetich, Takeshi Annoura, Cornelius C Hermsen, Audrey Lorthiois, Geert Leroux-Roels, Philip Meuleman, Martijn W. Vos, Lander Foquet, Dominique Mazier, Marga van de Vegte-Bolmer, and Geert-Jan van Gemert

Subjects
Plasmodium, PARASITES, PROTEIN, Drug resistance, Mice, GAMETOCYTES, vaccine, Biology (General), Malaria, Falciparum, PfSPZ, Mice, Inbred BALB C, Microbiology and Infectious Disease, Malaria vaccine, General Neuroscience, General Medicine, PROTECTIVE IMMUNITY, IMMUNIZATION, 3. Good health, LIVER-STAGE, Sporozoites, Medicine, Research Article, genetically attenuated parasite, QH301-705.5, Science, Plasmodium falciparum, malaria, Biology, Vaccines, Attenuated, liver, General Biochemistry, Genetics and Molecular Biology, In vivo, Malaria Vaccines, medicine, Gametocyte, Animals, Humans, sporozoite, INFECTIVITY, Plasmodium berghei, human, Human Biology and Medicine, PLASMODIUM-BERGHEI, mouse, General Immunology and Microbiology, other, genetically attenuated parasite (GAP), Biology and Life Sciences, medicine.disease, biology.organism_classification, Virology, HIGH-EFFICIENCY TRANSFECTION, Mice, Inbred C57BL, HUMAN HEPATOCYTES, Infectious disease (medical specialty), Immunology, Malaria
Abstract

A highly efficacious pre-erythrocytic stage vaccine would be an important tool for the control and elimination of malaria but is currently unavailable. High-level protection in humans can be achieved by experimental immunization with Plasmodium falciparum sporozoites attenuated by radiation or under anti-malarial drug coverage. Immunization with genetically attenuated parasites (GAP) would be an attractive alternative approach. In this study, we present data on safety and protective efficacy using sporozoites with deletions of two genes, that is the newly identified b9 and slarp, which govern independent and critical processes for successful liver-stage development. In the rodent malaria model, PbΔb9ΔslarpGAP was completely attenuated showing no breakthrough infections while efficiently inducing high-level protection. The human PfΔb9ΔslarpGAP generated without drug resistance markers were infective to human hepatocytes in vitro and to humanized mice engrafted with human hepatocytes in vivo but completely aborted development after infection. These findings support the clinical development of a PfΔb9ΔslarpSPZ vaccine. DOI: http://dx.doi.org/10.7554/eLife.03582.001, eLife digest Vaccines commonly contain a weakened or dead version of a disease-causing microorganism, or its toxins, or surface proteins. These prime the immune system to rapidly recognize, respond to, and eliminate the actual infectious pathogen if later encountered. While vaccines are currently available to help prevent a large number of diseases, vaccines for many deadly diseases, including malaria, do not yet exist. Malaria is caused by a group of parasites called Plasmodium, which are transferred to humans by mosquitoes. While measures to control mosquito populations and prevent mosquito bites have helped to reduce the incidence of malaria in some countries, the number of people—and especially children—that die of malaria every year remains very high. When a mosquito carrying Plasmodium in its salivary glands bites a human, the parasite is injected into the human's bloodstream and travels to the liver. The parasite reproduces in the liver cells until there are so many of them that the cells rupture, and the parasites are released back into the bloodstream. Any mosquito that then feeds on the blood of the infected individual may also suck up the parasite. The parasite then goes through a further stage of development in the mosquito, eventually migrating to the salivary glands, from where the parasite can be transmitted into a new human host. Recent work in rodents suggests that genetically altered or weakened Plasmodium falciparum sporozoites—the form of the parasite found in mosquito saliva—could be used to vaccinate humans against malaria caused by this parasite species. Now, van Schaijk, Ploemen et al. evaluate whether a safe and effective vaccine could be made from sporozoites that lack two genes, called b9 and slarp, which are critical for the parasites to develop inside liver cells. When mice were injected with the modified sporozoites, their immune cells were able to detect the parasites and respond against them. The mice subsequently did not develop malaria when they were infected with normal, unmodified parasites. Furthermore, none of the mice contracted malaria from the modified sporozoites. The modified sporozoites behaved similarly in human liver cells: after invading these cells, the parasites were unable to develop. Clinical testing and further development are now needed to see if a successful malaria vaccine can be made from these sporozoites. DOI: http://dx.doi.org/10.7554/eLife.03582.002

Published
2014

19. Author response: A genetically attenuated malaria vaccine candidate based on P. falciparum b9/slarp gene-deficient sporozoites

Author

Robert W. Sauerwein, Marga van de Vegte-Bolmer, Ivo H J Ploemen, Martijn W. Vos, Severine Chevalley-Maurel, Takeshi Annoura, Mohammed Sajid, Cornelius C Hermsen, Philip Meuleman, Ben C. L. van Schaijk, Dominique Mazier, Lander Foquet, Audrey Lorthiois, Geert-Jan van Gemert, Geert Leroux-Roels, Shahid M. Khan, Jean-François Franetich, Stephen L. Hoffman, and Chris J. Janse

Subjects
Malaria vaccine, Biology, Gene, Virology
Published
2014

20. P. falciparum Isolate-Specific Distinct Patterns of Induced Apoptosis in Pulmonary and Brain Endothelial Cells

Author

Alicia Moreno Sabater, Angelita Rebollo, Serge Bonnefoy, Nadine N'Dilimabaka, Georges Snounou, Sergine Zougbédé, Pierre Oliver Couraud, Dominique Mazier, Audrey Lorthiois, Zacharie Taoufiq, Immunité et Infection, Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR113-Université Pierre et Marie Curie - Paris 6 (UPMC), Immunologie moléculaire des parasites, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Institut Cochin (IC UM3 (UMR 8104 / U1016)), Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Service de parasitologie - mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), NN was supported by a fellowship from the Ministe`re des Affaires Etrange`res through the Ambassade de France at Libreville, Gabon., Université Pierre et Marie Curie - Paris 6 ( UPMC ) -IFR113-Institut National de la Santé et de la Recherche Médicale ( INSERM ), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique ( CNRS ), Institut Cochin ( UM3 (UMR 8104 / U1016) ), Université Paris Descartes - Paris 5 ( UPD5 ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ), Assistance publique - Hôpitaux de Paris (AP-HP)-CHU Pitié-Salpêtrière [APHP], Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR113-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Bos, Mireille, Service de Parasitologie - Mycologie [CHU Pitié-Salpétrière], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)

Subjects
Pulmonology, Cell, lcsh:Medicine, Apoptosis, Pathology and Laboratory Medicine, Epithelium, Pathogenesis, 0302 clinical medicine, Molecular Cell Biology, Medicine and Health Sciences, Malaria, Falciparum, lcsh:Science, Lung, Cells, Cultured, Protozoans, 0303 health sciences, Multidisciplinary, Cell Death, biology, Malarial Parasites, Brain, 3. Good health, Endothelial stem cell, Infectious Diseases, medicine.anatomical_structure, Neurology, Cell Processes, Cerebral Malaria, Anatomy, Cellular Types, Research Article, Clinical Pathology, Cerebrovascular Diseases, Plasmodium falciparum, 030231 tropical medicine, 03 medical and health sciences, parasitic diseases, Parasitic Diseases, Cell Adhesion, [SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology, medicine, Humans, Pulmonary Vascular Diseases, [SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology, Cell adhesion, [ SDV.BBM ] Life Sciences [q-bio]/Biochemistry, Molecular Biology, 030304 developmental biology, lcsh:R, Organisms, Biology and Life Sciences, Endothelial Cells, Epithelial Cells, Cell Biology, biology.organism_classification, medicine.disease, Parasitic Protozoans, Malaria, Biological Tissue, Immunology, lcsh:Q
Abstract

International audience; The factors implicated in the transition from uncomplicated to severe clinical malaria such as pulmonary oedema and cerebral malaria remain unclear. It is known that alterations in vascular integrity due to endothelial cell (EC) activation and death occur during severe malaria. In this study, we assessed the ability of different P. falciparum clinical isolates to induce apoptosis in ECs derived from human lung and brain. We observed that induction of EC apoptosis was sensitive to the environmental pH and required direct contact between the parasite and the cell, though it was not correlated to the ability of the parasite to cytoadhere. Moreover, the extent of induced apoptosis in the two EC types varied with the isolate. Analysis of parasite genes transcript led us to propose that the activation of different pathways, such as Plasmodium apoptosis–linked pathogenicity factors (PALPF), PALPF-2, PALPF-5 and PF11_0521, could be implied in EC death. These observations provide an experimental framework to decipher the molecular mechanism implicated in the genesis of severe malaria.

Published
2014

22. Persistence and activation of malaria hypnozoites in long-term primary hepatocyte cultures

Author

Jean-François Franetich, Audrey Lorthiois, Laurent Hannoun, Artur Scherf, Matthew J. Fuchter, Roger Le Grand, Thierry T. Diagana, Nicholas A. Malmquist, Jean-Christophe Vaillant, Dominique Mazier, Anne-Marie Zeeman, Geert-Jan van Gemert, Georges Snounou, Audrey Gego, Nathalie Dereuddre-Bosquet, Clemens H. M. Kocken, Robert W. Sauerwein, and Laurent Dembele

Subjects
Male, Time Factors, Primaquine, Green Fluorescent Proteins, Plasmodium vivax, lnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4], General Biochemistry, Genetics and Molecular Biology, Cell Line, Epigenesis, Genetic, Persistence (computer science), Histones, Mice, 03 medical and health sciences, Recurrence, parasitic diseases, medicine, Animals, Humans, Epigenetics, Cells, Cultured, 030304 developmental biology, Mice, Inbred BALB C, 0303 health sciences, biology, 030306 microbiology, Histone-Lysine N-Methyltransferase, General Medicine, biology.organism_classification, Plasmodium ovale, medicine.disease, Malaria, 3. Good health, medicine.anatomical_structure, Microscopy, Fluorescence, Sporozoites, Hepatocyte, Histone methyltransferase, Immunology, Hepatocytes, Histone Methyltransferases, Macaca, Female, Plasmodium cynomolgi, medicine.drug
Abstract

Malaria relapses, resulting from the activation of quiescent hepatic hypnozoites of Plasmodium vivax and Plasmodium ovale, hinder global efforts to control and eliminate malaria. As primaquine, the only drug capable of eliminating hypnozoites, is unsuitable for mass administration, an alternative drug is needed urgently. Currently, analyses of hypnozoites, including screening of compounds that would eliminate them, can only be made using common macaque models, principally Macaca rhesus and Macaca fascicularis, experimentally infected with the relapsing Plasmodium cynomolgi. Here, we present a protocol for long-term in vitro cultivation of P. cynomolgi-infected M. fascicularis primary hepatocytes during which hypnozoites persist and activate to resume normal development. In a proof-of-concept experiment, we obtained evidence that exposure to an inhibitor of histone modification enzymes implicated in epigenetic control of gene expression induces an accelerated rate of hypnozoite activation. The protocol presented may further enable investigations of hypnozoite biology and the search for compounds that kill hypnozoites or disrupt their quiescence.

Published
2014

23. Skin-draining lymph node priming is sufficient to induce sterile immunity against pre-erythrocytic malaria

Author

Michel Obeid, Jean-François Franetich, Georges Snounou, Audrey Gego, Maurel Tefit, Audrey Lorthiois, Claude Boucheix, Dominique Mazier, Anne Charlotte Grüner, Immunité et Infection, Université Pierre et Marie Curie - Paris 6 (UPMC)-IFR113-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Eco-Anthropologie et Ethnobiologie (EAE), Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Université Paris Diderot - Paris 7 (UPD7), Inserm UMR-S 1004, Université Paris-Sud - Paris 11 (UP11), Service de parasitologie - mycologie [CHU Pitié-Salpétrière], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Muséum national d'Histoire naturelle (MNHN)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), HAL UPMC, Gestionnaire, Service de Parasitologie - Mycologie [CHU Pitié-Salpétrière], and Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)

Subjects
liver-stage, Erythrocytes, Priming (immunology), Mice, Transgenic, Biology, 03 medical and health sciences, Mice, anti-malaria vaccination, [SDV.IMM.VAC] Life Sciences [q-bio]/Immunology/Vaccinology, 0302 clinical medicine, Immune system, Immunity, pre-erythrocytic immunity, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, Malaria Vaccines, medicine, Animals, Humans, dendritic cells, Lymph node, Research Articles, 030304 developmental biology, Skin, 0303 health sciences, Mice, Inbred BALB C, Plasmodium yoelii, skin vaccination approach, biochemical phenomena, metabolism, and nutrition, biology.organism_classification, Virology, 3. Good health, Malaria, Vaccination, medicine.anatomical_structure, Liver, Sporozoites, Hepatocyte, Immunology, [SDV.MHEP.MI] Life Sciences [q-bio]/Human health and pathology/Infectious diseases, Hepatocytes, Molecular Medicine, Female, Immunization, Lymph, Lymph Nodes, [SDV.IMM.VAC]Life Sciences [q-bio]/Immunology/Vaccinology, 030215 immunology
Abstract

International audience; The Plasmodium-infected hepatocyte has been considered necessary to prime the immune responses leading to sterile protection after vaccination with attenuated sporozoites. However, it has recently been demonstrated that priming also occurs in the skin. We wished to establish if sterile protection could be obtained in the absence of priming by infected hepatocytes. To this end, we developed a subcutaneous (s.c.) immunization protocol where few, possibly none, of the immunizing irradiated Plasmodium yoelii sporozoites infect hepatocytes, and also used CD81-deficient mice non-permissive to productive hepatocyte infections. We then compared and contrasted the patterns of priming with those obtained by intradermal immunization, where priming occurs in the liver. Using sterile immunity as a primary read-out, we exploited an inhibitor of T-cell migration, transgenic mice with conditional depletion of dendritic cells and adoptive transfers of draining lymph node-derived T cells, to provide evidence that responses leading to sterile immunity can be primed in the skin-draining lymph nodes with little, if any, contribution from the infected hepatocyte.

Published
2013

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