1
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Jennison C, Armstrong JM, Dankwa DA, Hertoghs N, Kumar S, Abatiyow BA, Naung M, Minkah NK, Swearingen KE, Moritz R, Barry AE, Kappe SHI, Vaughan AM. Plasmodium GPI-anchored micronemal antigen is essential for parasite transmission through the mosquito host. Mol Microbiol 2024; 121:394-412. [PMID: 37314965 PMCID: PMC11076100 DOI: 10.1111/mmi.15078] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/03/2023] [Accepted: 05/08/2023] [Indexed: 06/16/2023]
Abstract
Plasmodium parasites, the eukaryotic pathogens that cause malaria, feature three distinct invasive forms tailored to the host environment they must navigate and invade for life cycle progression. One conserved feature of these invasive forms is the micronemes, apically oriented secretory organelles involved in egress, motility, adhesion, and invasion. Here we investigate the role of GPI-anchored micronemal antigen (GAMA), which shows a micronemal localization in all zoite forms of the rodent-infecting species Plasmodium berghei. ∆GAMA parasites are severely defective for invasion of the mosquito midgut. Once formed, oocysts develop normally, however, sporozoites are unable to egress and exhibit defective motility. Epitope-tagging of GAMA revealed tight temporal expression late during sporogony and showed that GAMA is shed during sporozoite gliding motility in a similar manner to circumsporozoite protein. Complementation of P. berghei knockout parasites with full-length P. falciparum GAMA partially restored infectivity to mosquitoes, indicating conservation of function across Plasmodium species. A suite of parasites with GAMA expressed under the promoters of CTRP, CAP380, and TRAP, further confirmed the involvement of GAMA in midgut infection, motility, and vertebrate infection. These data show GAMA's involvement in sporozoite motility, egress, and invasion, implicating GAMA as a regulator of microneme function.
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Affiliation(s)
- Charlie Jennison
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Janna M. Armstrong
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Dorender A. Dankwa
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Nina Hertoghs
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Sudhir Kumar
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Biley A. Abatiyow
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Myo Naung
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Victoria, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Victoria, Carlton, Australia
- Department of Global Health, University of Washington, Washington, Seattle, USA
| | - Nana K. Minkah
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
| | - Kristian E. Swearingen
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Victoria, Geelong, Australia
| | - Robert Moritz
- Institute of Mental and Physical Health and Clinical Translation (IMPACT), School of Medicine, Deakin University, Victoria, Geelong, Australia
| | - Alyssa E. Barry
- Department of Global Health, University of Washington, Washington, Seattle, USA
- Institute for Systems Biology, Washington, Seattle, USA
| | - Stefan H. I. Kappe
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
- Burnet Institute, Victoria, Melbourne, Australia
- Department of Pediatrics, University of Washington, Washington, Seattle, USA
| | - Ashley M. Vaughan
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Washington, Seattle, USA
- Burnet Institute, Victoria, Melbourne, Australia
- Department of Pediatrics, University of Washington, Washington, Seattle, USA
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2
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Reber S, Singer M, Frischknecht F. Cytoskeletal dynamics in parasites. Curr Opin Cell Biol 2024; 86:102277. [PMID: 38048658 DOI: 10.1016/j.ceb.2023.102277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 10/12/2023] [Accepted: 10/17/2023] [Indexed: 12/06/2023]
Abstract
Cytoskeletal dynamics are essential for cellular homeostasis and development for both metazoans and protozoans. The function of cytoskeletal elements in protozoans can diverge from that of metazoan cells, with microtubules being more stable and actin filaments being more dynamic. This is particularly striking in protozoan parasites that evolved to enter metazoan cells. Here, we review recent progress towards understanding cytoskeletal dynamics in protozoan parasites, with a focus on divergent properties compared to classic model organisms.
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Affiliation(s)
- Simone Reber
- Max Planck Institute for Infection Biology, 10117 Berlin, Germany; University of Applied Sciences Berlin, 13353 Berlin, Germany
| | - Mirko Singer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical Faculty, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; German Center for Infection Research, DZIF Partner Site Heidelberg, Heidelberg, Germany.
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical Faculty, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany; German Center for Infection Research, DZIF Partner Site Heidelberg, Heidelberg, Germany
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3
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Deligianni E, Pizzi E, Kavelaki I, Siden-Kiamos I, Sapienza FU, Fioravanti R, Garzoli S, Pace T, Ponzi M, Ragno R, Currà C. Screening of the activity of sixty essential oils against plasmodium early mosquito stages in vitro and machine learning analysis reveals new putative inhibitors of malaria parasites. Int J Parasitol Drugs Drug Resist 2023; 23:87-93. [PMID: 38000094 PMCID: PMC10709126 DOI: 10.1016/j.ijpddr.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 10/20/2023] [Accepted: 11/08/2023] [Indexed: 11/26/2023]
Abstract
Malaria, an infectious disease with a tremendous impact on human health is caused by Plasmodium parasites, and transmitted by Anopheles mosquitoes. New approaches to control the disease involve transmission blocking strategies aiming to target the parasite in the mosquito. Here, we investigated the putative inhibitory activity of essential oils and their components on the early mosquito stages of the parasite. We employed an in vitro assay of gametocyte-to-ookinete development of the rodent model parasite Plasmodium berghei combined with high content screening. 60 essential oils with known composition were tested. The results revealed that fifteen EOs had inhibitory activity. Furthermore, a machine learning approach was used to identify the putative inhibitory components. Five of the most important chemical components indicated by the machine learning-based models were actually confirmed by the experimental approach. This combined approach was used for the first time to identify the potential transmission blocking activity of essential oils and single components at the zygote and ookinete stages.
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Affiliation(s)
- Elena Deligianni
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece
| | - Elisabetta Pizzi
- Servizio Grandi Strumentazioni e Core Facilities, Istituto Superiore di Sanità, Rome, Italy
| | - Ioanna Kavelaki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece
| | - Filippo Umberto Sapienza
- Rome Center for Molecular Design-RCMD, Department of Drug Chemistry and Technology, University Sapienza of Rome, Italy
| | - Rossella Fioravanti
- Department of Drug Chemistry and Technology, University Sapienza of Rome, Rome, Italy
| | - Stefania Garzoli
- Department of Drug Chemistry and Technology, University Sapienza of Rome, Rome, Italy
| | - Tomasino Pace
- Dipartimento di Malattie Infettive, Istituto Superiore di Sanità, Rome, Italy
| | - Marta Ponzi
- Dipartimento di Malattie Infettive, Istituto Superiore di Sanità, Rome, Italy
| | - Rino Ragno
- Department of Drug Chemistry and Technology, University Sapienza of Rome, Rome, Italy.
| | - Chiara Currà
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology - Hellas, Heraklion, Greece.
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4
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Ouologuem DT, Dara A, Kone A, Ouattara A, Djimde AA. Plasmodium falciparum Development from Gametocyte to Oocyst: Insight from Functional Studies. Microorganisms 2023; 11:1966. [PMID: 37630530 PMCID: PMC10460021 DOI: 10.3390/microorganisms11081966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/06/2023] [Accepted: 07/14/2023] [Indexed: 08/27/2023] Open
Abstract
Malaria elimination may never succeed without the implementation of transmission-blocking strategies. The transmission of Plasmodium spp. parasites from the human host to the mosquito vector depends on circulating gametocytes in the peripheral blood of the vertebrate host. Once ingested by the mosquito during blood meals, these sexual forms undergo a series of radical morphological and metabolic changes to survive and progress from the gut to the salivary glands, where they will be waiting to be injected into the vertebrate host. The design of effective transmission-blocking strategies requires a thorough understanding of all the mechanisms that drive the development of gametocytes, gametes, sexual reproduction, and subsequent differentiation within the mosquito. The drastic changes in Plasmodium falciparum shape and function throughout its life cycle rely on the tight regulation of stage-specific gene expression. This review outlines the mechanisms involved in Plasmodium falciparum sexual stage development in both the human and mosquito vector, and zygote to oocyst differentiation. Functional studies unravel mechanisms employed by P. falciparum to orchestrate the expression of stage-specific functional products required to succeed in its complex life cycle, thus providing us with potential targets for developing new therapeutics. These mechanisms are based on studies conducted with various Plasmodium species, including predominantly P. falciparum and the rodent malaria parasites P. berghei. However, the great potential of epigenetics, genomics, transcriptomics, proteomics, and functional genetic studies to improve the understanding of malaria as a disease remains partly untapped because of limitations in studies using human malaria parasites and field isolates.
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Affiliation(s)
- Dinkorma T. Ouologuem
- Malaria Research and Training Center, Faculty of Pharmacy, Faculty of Medicine and Dentistry, University of Sciences, Techniques, and Technologies of Bamako, Bamako 1805, Mali
| | - Antoine Dara
- Malaria Research and Training Center, Faculty of Pharmacy, Faculty of Medicine and Dentistry, University of Sciences, Techniques, and Technologies of Bamako, Bamako 1805, Mali
| | - Aminatou Kone
- Malaria Research and Training Center, Faculty of Pharmacy, Faculty of Medicine and Dentistry, University of Sciences, Techniques, and Technologies of Bamako, Bamako 1805, Mali
| | - Amed Ouattara
- Malaria Research Program, Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Abdoulaye A. Djimde
- Malaria Research and Training Center, Faculty of Pharmacy, Faculty of Medicine and Dentistry, University of Sciences, Techniques, and Technologies of Bamako, Bamako 1805, Mali
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5
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Parres-Mercader M, Pance A, Gómez-Díaz E. Novel systems to study vector-pathogen interactions in malaria. Front Cell Infect Microbiol 2023; 13:1146030. [PMID: 37305421 PMCID: PMC10253182 DOI: 10.3389/fcimb.2023.1146030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 04/04/2023] [Indexed: 06/13/2023] Open
Abstract
Some parasitic diseases, such as malaria, require two hosts to complete their lifecycle: a human and an insect vector. Although most malaria research has focused on parasite development in the human host, the life cycle within the vector is critical for the propagation of the disease. The mosquito stage of the Plasmodium lifecycle represents a major demographic bottleneck, crucial for transmission blocking strategies. Furthermore, it is in the vector, where sexual recombination occurs generating "de novo" genetic diversity, which can favor the spread of drug resistance and hinder effective vaccine development. However, understanding of vector-parasite interactions is hampered by the lack of experimental systems that mimic the natural environment while allowing to control and standardize the complexity of the interactions. The breakthrough in stem cell technologies has provided new insights into human-pathogen interactions, but these advances have not been translated into insect models. Here, we review in vivo and in vitro systems that have been used so far to study malaria in the mosquito. We also highlight the relevance of single-cell technologies to progress understanding of these interactions with higher resolution and depth. Finally, we emphasize the necessity to develop robust and accessible ex vivo systems (tissues and organs) to enable investigation of the molecular mechanisms of parasite-vector interactions providing new targets for malaria control.
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Affiliation(s)
- Marina Parres-Mercader
- Instituto de Parasitología y Biomedicina López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN, CSIC), Granada, Spain
| | - Alena Pance
- School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom
| | - Elena Gómez-Díaz
- Instituto de Parasitología y Biomedicina López-Neyra, Consejo Superior de Investigaciones Científicas (IPBLN, CSIC), Granada, Spain
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6
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Dans MG, Piirainen H, Nguyen W, Khurana S, Mehra S, Razook Z, Geoghegan ND, Dawson AT, Das S, Parkyn Schneider M, Jonsdottir TK, Gabriela M, Gancheva MR, Tonkin CJ, Mollard V, Goodman CD, McFadden GI, Wilson DW, Rogers KL, Barry AE, Crabb BS, de Koning-Ward TF, Sleebs BE, Kursula I, Gilson PR. Sulfonylpiperazine compounds prevent Plasmodium falciparum invasion of red blood cells through interference with actin-1/profilin dynamics. PLoS Biol 2023; 21:e3002066. [PMID: 37053271 PMCID: PMC10128974 DOI: 10.1371/journal.pbio.3002066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 04/25/2023] [Accepted: 03/06/2023] [Indexed: 04/15/2023] Open
Abstract
With emerging resistance to frontline treatments, it is vital that new antimalarial drugs are identified to target Plasmodium falciparum. We have recently described a compound, MMV020291, as a specific inhibitor of red blood cell (RBC) invasion, and have generated analogues with improved potency. Here, we generated resistance to MMV020291 and performed whole genome sequencing of 3 MMV020291-resistant populations. This revealed 3 nonsynonymous single nucleotide polymorphisms in 2 genes; 2 in profilin (N154Y, K124N) and a third one in actin-1 (M356L). Using CRISPR-Cas9, we engineered these mutations into wild-type parasites, which rendered them resistant to MMV020291. We demonstrate that MMV020291 reduces actin polymerisation that is required by the merozoite stage parasites to invade RBCs. Additionally, the series inhibits the actin-1-dependent process of apicoplast segregation, leading to a delayed death phenotype. In vitro cosedimentation experiments using recombinant P. falciparum proteins indicate that potent MMV020291 analogues disrupt the formation of filamentous actin in the presence of profilin. Altogether, this study identifies the first compound series interfering with the actin-1/profilin interaction in P. falciparum and paves the way for future antimalarial development against the highly dynamic process of actin polymerisation.
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Affiliation(s)
- Madeline G Dans
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Henni Piirainen
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - William Nguyen
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Sachin Khurana
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Somya Mehra
- Burnet Institute, Melbourne, Victoria, Australia
| | - Zahra Razook
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | | | | | - Sujaan Das
- Ludwig Maximilian University, Faculty of Veterinary Medicine, Munich, Germany
| | | | - Thorey K Jonsdottir
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Mikha Gabriela
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Maria R Gancheva
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | | | - Vanessa Mollard
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | | | - Geoffrey I McFadden
- School of Biosciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Danny W Wilson
- Research Centre for Infectious Diseases, The University of Adelaide, Adelaide, Australia
| | - Kelly L Rogers
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Alyssa E Barry
- Burnet Institute, Melbourne, Victoria, Australia
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brendan S Crabb
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
| | - Tania F de Koning-Ward
- School of Medicine and Institute for Mental and Physical Health and Clinical Translation, Deakin University, Waurn Ponds, Victoria, Australia
| | - Brad E Sleebs
- Walter and Eliza Hall Institute, Parkville, Victoria, Australia
| | - Inari Kursula
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Paul R Gilson
- Burnet Institute, Melbourne, Victoria, Australia
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
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7
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San Anselmo M, Lantero E, Avalos-Padilla Y, Bouzón-Arnáiz I, Ramírez M, Postigo A, Serrano JL, Sierra T, Hernández-Ainsa S, Fernàndez-Busquets X. Heparin-Coated Dendronized Hyperbranched Polymers for Antimalarial Targeted Delivery. ACS APPLIED POLYMER MATERIALS 2023; 5:381-390. [PMID: 36686062 PMCID: PMC9844211 DOI: 10.1021/acsapm.2c01553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 12/08/2022] [Indexed: 06/17/2023]
Abstract
The rampant evolution of resistance in Plasmodium to all existing antimalarial drugs calls for the development of improved therapeutic compounds and of adequate targeted delivery strategies for them. Loading antimalarials in nanocarriers specifically targeted to the parasite will contribute to the administration of lower overall doses, with reduced side effects for the patient, and of higher local amounts to parasitized cells for an increased lethality toward the pathogen. Here, we report the development of dendronized hyperbranched polymers (DHPs), with capacity for antimalarial loading, that are coated with heparin for their specific targeting to red blood cells parasitized by Plasmodium falciparum. The resulting DHP-heparin complexes exhibit the intrinsic antimalarial activity of heparin, with an IC50 of ca. 400 nM, added to its specific targeting to P. falciparum-infected (vs noninfected) erythrocytes. DHP-heparin nanocarriers represent a potentially interesting contribution to the limited family of structures described so far for the loading and targeted delivery of current and future antimalarial compounds.
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Affiliation(s)
- María San Anselmo
- Instituto
de Nanociencia y Materiales de Aragón (INMA), Departamento
de Química Orgánica-Facultad de Ciencias, CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain
| | - Elena Lantero
- Nanomalaria
Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Barcelona
Institute for Global Health (ISGlobal, Hospital Clínic-Universitat
de Barcelona), Rosselló
149-153, Barcelona 08036, Spain
- Nanoscience
and Nanotechnology Institute (IN2UB), University
of Barcelona, Martí
I Franquès 1, Barcelona 08028, Spain
| | - Yunuen Avalos-Padilla
- Nanomalaria
Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Barcelona
Institute for Global Health (ISGlobal, Hospital Clínic-Universitat
de Barcelona), Rosselló
149-153, Barcelona 08036, Spain
- Nanoscience
and Nanotechnology Institute (IN2UB), University
of Barcelona, Martí
I Franquès 1, Barcelona 08028, Spain
| | - Inés Bouzón-Arnáiz
- Nanomalaria
Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Barcelona
Institute for Global Health (ISGlobal, Hospital Clínic-Universitat
de Barcelona), Rosselló
149-153, Barcelona 08036, Spain
- Nanoscience
and Nanotechnology Institute (IN2UB), University
of Barcelona, Martí
I Franquès 1, Barcelona 08028, Spain
| | - Miriam Ramírez
- Nanomalaria
Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Barcelona
Institute for Global Health (ISGlobal, Hospital Clínic-Universitat
de Barcelona), Rosselló
149-153, Barcelona 08036, Spain
- Nanoscience
and Nanotechnology Institute (IN2UB), University
of Barcelona, Martí
I Franquès 1, Barcelona 08028, Spain
| | - Alejandro Postigo
- Instituto
de Nanociencia y Materiales de Aragón (INMA), Departamento
de Química Orgánica-Facultad de Ciencias, CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain
| | - José Luis Serrano
- Instituto
de Nanociencia y Materiales de Aragón (INMA), Departamento
de Química Orgánica-Facultad de Ciencias, CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain
| | - Teresa Sierra
- Instituto
de Nanociencia y Materiales de Aragón (INMA), Departamento
de Química Orgánica-Facultad de Ciencias, CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain
| | - Silvia Hernández-Ainsa
- Instituto
de Nanociencia y Materiales de Aragón (INMA), Departamento
de Química Orgánica-Facultad de Ciencias, CSIC-Universidad de Zaragoza, Zaragoza 50009, Spain
- ARAID
Foundation, Government of Aragón, Zaragoza 50018, Spain
| | - Xavier Fernàndez-Busquets
- Nanomalaria
Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, Barcelona 08028, Spain
- Barcelona
Institute for Global Health (ISGlobal, Hospital Clínic-Universitat
de Barcelona), Rosselló
149-153, Barcelona 08036, Spain
- Nanoscience
and Nanotechnology Institute (IN2UB), University
of Barcelona, Martí
I Franquès 1, Barcelona 08028, Spain
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8
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Transcending Dimensions in Apicomplexan Research: from Two-Dimensional to Three-Dimensional In Vitro Cultures. Microbiol Mol Biol Rev 2022; 86:e0002522. [PMID: 35412359 PMCID: PMC9199416 DOI: 10.1128/mmbr.00025-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Parasites belonging to the Apicomplexa phylum are among the most successful pathogens known in nature. They can infect a wide range of hosts, often remain undetected by the immune system, and cause acute and chronic illness. In this phylum, we can find parasites of human and veterinary health relevance, such as Toxoplasma, Plasmodium, Cryptosporidium, and Eimeria. There are still many unknowns about the biology of these pathogens due to the ethical and practical issues of performing research in their natural hosts. Animal models are often difficult or nonexistent, and as a result, there are apicomplexan life cycle stages that have not been studied. One recent alternative has been the use of three-dimensional (3D) systems such as organoids, 3D scaffolds with different matrices, microfluidic devices, organs-on-a-chip, and other tissue culture models. These 3D systems have facilitated and expanded the research of apicomplexans, allowing us to explore life stages that were previously out of reach and experimental procedures that were practically impossible to perform in animal models. Human- and animal-derived 3D systems can be obtained from different organs, allowing us to model host-pathogen interactions for diagnostic methods and vaccine development, drug testing, exploratory biology, and other applications. In this review, we summarize the most recent advances in the use of 3D systems applied to apicomplexans. We show the wide array of strategies that have been successfully used so far and apply them to explore other organisms that have been less studied.
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9
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Stadler RV, Nelson SR, Warshaw DM, Ward GE. A circular zone of attachment to the extracellular matrix provides directionality to the motility of Toxoplasma gondii in 3D. eLife 2022; 11:85171. [PMID: 36519527 PMCID: PMC9839348 DOI: 10.7554/elife.85171] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
Toxoplasma gondii is a protozoan parasite that infects 30-40% of the world's population. Infections are typically subclinical but can be severe and, in some cases, life threatening. Central to the virulence of T. gondii is an unusual form of substrate-dependent motility that enables the parasite to invade cells of its host and to disseminate throughout the body. A hetero-oligomeric complex of proteins that functions in motility has been characterized, but how these proteins work together to drive forward motion of the parasite remains controversial. A key piece of information needed to understand the underlying mechanism(s) is the directionality of the forces that a moving parasite exerts on the external environment. The linear motor model of motility, which has dominated the field for the past two decades, predicts continuous anterior-to-posterior force generation along the length of the parasite. We show here using three-dimensional traction force mapping that the predominant forces exerted by a moving parasite are instead periodic and directed in toward the parasite at a fixed circular location within the extracellular matrix. These highly localized forces, which are generated by the parasite pulling on the matrix, create a visible constriction in the parasite's plasma membrane. We propose that the ring of inward-directed force corresponds to a circumferential attachment zone between the parasite and the matrix, through which the parasite propels itself to move forward. The combined data suggest a closer connection between the mechanisms underlying parasite motility and host cell invasion than previously recognized. In parasites lacking the major surface adhesin, TgMIC2, neither the inward-directed forces nor the constriction of the parasite membrane are observed. The trajectories of the TgMIC2-deficient parasites are less straight than those of wild-type parasites, suggesting that the annular zone of TgMIC2-mediated attachment to the extracellular matrix normally constrains the directional options available to the parasite as it migrates through its surrounding environment.
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Affiliation(s)
- Rachel V Stadler
- Department of Microbiology and Molecular Genetics, University of Vermont Larner College of MedicineBurlingtonUnited States
| | - Shane R Nelson
- Department of Molecular Physiology and Biophysics, University of Vermont Larner College of MedicineBurlingtonUnited States
| | - David M Warshaw
- Department of Molecular Physiology and Biophysics, University of Vermont Larner College of MedicineBurlingtonUnited States
| | - Gary E Ward
- Department of Microbiology and Molecular Genetics, University of Vermont Larner College of MedicineBurlingtonUnited States
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10
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Ridgway MC, Cihalova D, Brown SHJ, Tran P, Mitchell TW, Maier AG. Analysis of sex-specific lipid metabolism of P. falciparum points to importance of sphingomyelin for gametocytogenesis. J Cell Sci 2021; 135:273669. [PMID: 34881783 DOI: 10.1242/jcs.259592] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 11/18/2021] [Indexed: 11/20/2022] Open
Abstract
Male and female Plasmodium falciparum gametocytes are the parasite lifecycle stage responsible for transmission of malaria from the human host to mosquito vector. Not only are gametocytes able to survive in radically different host environments, but they are also precursors for male and female gametes that reproduce sexually soon after ingestion by the mosquito. Here we investigate the sex-specific lipid metabolism of gametocytes within their host red blood cell. Comparison of the male and female lipidome identifies cholesteryl esters and dihydrosphingomyelin enrichment in female gametocytes. Chemical inhibition of each of these lipid types in mature gametocytes suggests dihydrosphingomyelin synthesis but not cholesteryl ester synthesis is important for gametocyte viability. Genetic disruption of each of the two sphingomyelin synthase gene points towards sphingomyelin synthesis contributing to gametocytogenesis. This study shows that gametocytes are distinct from asexual stages, and that the lipid composition is also vastly different between male and female gametocytes, reflecting the different cellular roles these stages play. Together our results highlight the sex-specific nature of gametocyte lipid metabolism that has the potential to be targeted to block malaria transmission.
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Affiliation(s)
- Melanie C Ridgway
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Daniela Cihalova
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Simon H J Brown
- Molecular Horizons and School of Chemistry and Molecular Biology, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Phuong Tran
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Todd W Mitchell
- Illawarra Health and Medical Research Institute and School of Medicine, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Alexander G Maier
- Research School of Biology, Australian National University, Canberra, Australian Capital Territory 2601, Australia
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11
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Bantuchai S, Imad H, Nguitragool W. Plasmodium vivax gametocytes and transmission. Parasitol Int 2021; 87:102497. [PMID: 34748969 DOI: 10.1016/j.parint.2021.102497] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 08/14/2021] [Accepted: 10/30/2021] [Indexed: 10/19/2022]
Abstract
Malaria elimination means cessation of parasite transmission. At present, the declining malaria incidence in many countries has made elimination a feasible goal. Transmission control has thus been placed at the center of the national malaria control programs. The efficient transmission of Plasmodium vivax from humans to mosquitoes is a key factor that helps perpetuate malaria in endemic areas. A better understanding of transmission is crucial to the success of elimination efforts. Biological delineation of the parasite transmission process is important for identifying and prioritizing new targets of intervention. Identification of the infectious parasite reservoir in the community is key to devising an effective elimination strategy. Here we describe the fundamental characteristics of P. vivax gametocytes - the dynamics of their production, longevity, and the relationship with the total parasitemia - as well as recent advances in the molecular understanding of parasite sexual development. In relation to malaria elimination, factors influencing the human infectivity and the current evidence for a role of asymptomatic carriers in transmission are presented.
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Affiliation(s)
- Sirasate Bantuchai
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand.
| | - Hisham Imad
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand.
| | - Wang Nguitragool
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand; Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand.
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12
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Nakayama K, Kimura Y, Kitahara Y, Soga A, Haraguchi A, Hakozaki J, Sugiyama M, Kusakisako K, Fukumoto S, Ikadai H. Role of Plasmodium berghei ookinete surface and oocyst capsule protein, a novel oocyst capsule-associated protein, in ookinete motility. Parasit Vectors 2021; 14:373. [PMID: 34289894 PMCID: PMC8296654 DOI: 10.1186/s13071-021-04868-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 06/30/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Plasmodium sp., which causes malaria, must first develop in mosquitoes before being transmitted. Upon ingesting infected blood, gametes form in the mosquito lumen, followed by fertilization and differentiation of the resulting zygotes into motile ookinetes. Within 24 h of blood ingestion, these ookinetes traverse mosquito epithelial cells and lodge below the midgut basal lamina, where they differentiate into sessile oocysts that are protected by a capsule. METHODS We identified an ookinete surface and oocyst capsule protein (OSCP) that is involved in ookinete motility as well as oocyst capsule formation. RESULTS We found that knockout of OSCP in parasite decreases ookinete gliding motility and gradually reduces the number of oocysts. On day 15 after blood ingestion, the oocyst wall was significantly thinner. Moreover, adding anti-OSCP antibodies decreased the gliding speed of wild-type ookinetes in vitro. Adding anti-OSCP antibodies to an infected blood meal also resulted in decreased oocyst formation. CONCLUSION These findings may be useful for the development of a transmission-blocking tool for malaria.
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Affiliation(s)
- Kazuhiko Nakayama
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Yuta Kimura
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Yu Kitahara
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Akira Soga
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, 080-8555, Japan
| | - Asako Haraguchi
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Jun Hakozaki
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Makoto Sugiyama
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Kodai Kusakisako
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Shinya Fukumoto
- National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada, Obihiro, 080-8555, Japan
| | - Hiromi Ikadai
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
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13
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Ripp J, Kehrer J, Smyrnakou X, Tisch N, Tavares J, Amino R, Ruiz de Almodovar C, Frischknecht F. Malaria parasites differentially sense environmental elasticity during transmission. EMBO Mol Med 2021; 13:e13933. [PMID: 33666362 PMCID: PMC8033522 DOI: 10.15252/emmm.202113933] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 12/13/2022] Open
Abstract
Transmission of malaria-causing parasites to and by the mosquito relies on active parasite migration and constitutes bottlenecks in the Plasmodium life cycle. Parasite adaption to the biochemically and physically different environments must hence be a key evolutionary driver for transmission efficiency. To probe how subtle but physiologically relevant changes in environmental elasticity impact parasite migration, we introduce 2D and 3D polyacrylamide gels to study ookinetes, the parasite forms emigrating from the mosquito blood meal and sporozoites, the forms transmitted to the vertebrate host. We show that ookinetes adapt their migratory path but not their speed to environmental elasticity and are motile for over 24 h on soft substrates. In contrast, sporozoites evolved more short-lived rapid gliding motility for rapidly crossing the skin. Strikingly, sporozoites are highly sensitive to substrate elasticity possibly to avoid adhesion to soft endothelial cells on their long way to the liver. Hence, the two migratory stages of Plasmodium evolved different strategies to overcome the physical challenges posed by the respective environments and barriers they encounter.
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Affiliation(s)
- Johanna Ripp
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Jessica Kehrer
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Xanthoula Smyrnakou
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
- Gene Therapy for Hearing Impairment and DeafnessDepartment of OtolaryngologyHead & Neck SurgeryUniversity of Tübingen Medical CenterTübingenGermany
| | - Nathalie Tisch
- Biochemistry CenterHeidelberg UniversityHeidelbergGermany
- European Center for Angioscience (ECAS)Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Joana Tavares
- IBMC‐Institute for Molecular and Cell Biologyi3S ‐ Institute for Research and Innovation in HealthUniversity of PortoPortoPortugal
- Malaria Infection and Immunity UnitDepartment of Parasites and Insect VectorsInstitut PasteurParisFrance
| | - Rogerio Amino
- Malaria Infection and Immunity UnitDepartment of Parasites and Insect VectorsInstitut PasteurParisFrance
| | - Carmen Ruiz de Almodovar
- Biochemistry CenterHeidelberg UniversityHeidelbergGermany
- European Center for Angioscience (ECAS)Medical Faculty MannheimHeidelberg UniversityMannheimGermany
| | - Friedrich Frischknecht
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
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14
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Lozano JM, Rodríguez Parra Z, Hernández-Martínez S, Yasnot-Acosta MF, Rojas AP, Marín-Waldo LS, Rincón JE. The Search of a Malaria Vaccine: The Time for Modified Immuno-Potentiating Probes. Vaccines (Basel) 2021; 9:vaccines9020115. [PMID: 33540947 PMCID: PMC7913233 DOI: 10.3390/vaccines9020115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 12/25/2022] Open
Abstract
Malaria is a deadly disease that takes the lives of more than 420,000 people a year and is responsible for more than 229 million clinical cases globally. In 2019, 95% of malaria morbidity occurred in African countries. The development of a highly protective vaccine is an urgent task that remains to be solved. Many vaccine candidates have been developed, from the use of the entire attenuated and irradiated pre-erythrocytic parasite forms (or recombinantly expressed antigens thereof) to synthetic candidates formulated in a variety of adjuvants and delivery systems, however these have unfortunately proven a limited efficacy. At present, some vaccine candidates are finishing safety and protective efficacy trials, such as the PfSPZ and the RTS,S/AS01 which are being introduced in Africa. We propose a strategy for introducing non-natural elements into target antigens representing key epitopes of Plasmodium spp. Accordingly, chemical strategies and knowledge of host immunity to Plasmodium spp. have served as the basis. Evidence is obtained after being tested in experimental rodent models for malaria infection and recognized for human sera from malaria-endemic regions. This encourages us to propose such an immune-potentiating strategy to be further considered in the search for new vaccine candidates.
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Affiliation(s)
- José Manuel Lozano
- Grupo de Investigación Mimetismo Molecular de los Agentes Infecciosos, Departamento de Farmacia, Universidad Nacional de Colombia—Sede Bogotá, 111321 Bogota, Colombia;
- Correspondence: ; Tel.: +57-3102-504-657
| | - Zully Rodríguez Parra
- Grupo de Investigación Mimetismo Molecular de los Agentes Infecciosos, Departamento de Farmacia, Universidad Nacional de Colombia—Sede Bogotá, 111321 Bogota, Colombia;
| | - Salvador Hernández-Martínez
- Dirección de Infección e Inmunidad, Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, 62508 Cuernavaca, Morelos, Mexico;
| | - Maria Fernanda Yasnot-Acosta
- Grupo de Investigaciones Microbiológicas y Biomédicas de Córdoba, Universidad de Córdoba, 230002 Monteria, Colombia;
| | - Angela Patricia Rojas
- Grupo de Investigación Biología Celular y Autoinmuniad, Departamento de Farmacia, Universidad Nacional de Colombia-Sede Bogotá, 111321 Bogota, Colombia;
| | | | - Juan Edilberto Rincón
- Departamento de Ingeniería y Mecatrónica, Universidad Nacional de Colombia-Sede Bogotá, 111321 Bogota, Colombia;
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15
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McCrea AR, Edgerton EB, Oliver GT, O'Neill FM, Nolan TJ, Lok JB, Povelones M. A novel assay to isolate and quantify third-stage Dirofilaria immitis and Brugia malayi larvae emerging from individual Aedes aegypti. Parasit Vectors 2021; 14:30. [PMID: 33413579 PMCID: PMC7789620 DOI: 10.1186/s13071-020-04529-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 12/07/2020] [Indexed: 11/11/2022] Open
Abstract
Background Mosquitoes transmit filarial nematodes to both human and animal hosts, with worldwide health and economic consequences. Transmission to a vertebrate host requires that ingested microfilariae develop into infective third-stage larvae capable of emerging from the mosquito proboscis onto the skin of the host during blood-feeding. Determining the number of microfilariae that successfully develop to infective third-stage larvae in the mosquito host is key to understanding parasite transmission potential and to developing new strategies to block these worms in their vector. Methods We developed a novel method to efficiently assess the number of infective third-stage filarial larvae that emerge from experimentally infected mosquitoes. Following infection, individual mosquitoes were placed in wells of a multi-well culture plate and warmed to 37 °C to stimulate parasite emergence. Aedes aegypti infected with Dirofilaria immitis were used to determine infection conditions and assay timing. The assay was also tested with Brugia malayi-infected Ae. aegypti. Results Approximately 30% of Ae. aegypti infected with D. immitis and 50% of those infected with B. malayi produced emerging third-stage larvae. Once D. immitis third-stage larvae emerged at 13 days post infection, the proportion of mosquitoes producing them and the number produced per mosquito remained stable until at least day 21. The prevalence and intensity of emerging third-stage B. malayi were similar on days 12–14 post infection. Increased uptake of D. immitis microfilariae increased the fitness cost to the mosquito but did not increase the number of emerging third-stage larvae. Conclusions We provide a new assay with an associated set of infection conditions that will facilitate assessment of the filarial transmission potential of mosquito vectors and promote preparation of uniformly infectious third-stage larvae for functional assays. The ability to quantify infection outcome will facilitate analyses of molecular interactions between vectors and filariae, ultimately allowing for the establishment of novel methods to block disease transmission. ![]()
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Affiliation(s)
- Abigail R McCrea
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Elizabeth B Edgerton
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Genevieve T Oliver
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Fiona M O'Neill
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Thomas J Nolan
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - James B Lok
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Michael Povelones
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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16
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Afifi MA. The Parasites Caught In-Action: Imaging at the Host-Parasite Interface. J Microsc Ultrastruct 2021; 9:1-6. [PMID: 33850705 PMCID: PMC8030542 DOI: 10.4103/jmau.jmau_1_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 01/02/2020] [Accepted: 01/21/2020] [Indexed: 11/24/2022] Open
Abstract
For many decades, scientists were unable to expose the invisible existence of the parasites in their living hosts, except by scarification and then dissection of the animal model. This process just demonstrates a dead parasite in a dead host. Using this approach, very limited information can be obtained concerning the dynamics of infection and the pathways utilized by the parasite to survive within a hostile host's environment. Introduction of ultra-high-speed imaging techniques, with a time domain of barely few microseconds or even less, has revolutionized the "in vivo dissection" of the parasites. Such methods provide platforms for imaging host-parasite interactions at diverse scales, down to the molecular level. These have complementary advantages and relative assets in investigating host-parasite interactions. Therefore, better elucidation of such interaction may require the usage of more than one approach. Precise in vivo quantification, of the parasite load within the host, and better insight into the kinetics of infection are the two main advantages of the novel imaging procedures. However, imaging parasite-host interplay is still a challenging approach due to many constraints related to the parasite biology, the tissue environment within which the parasites exist, and the logistic technical limitations. This review was planned to assist better understanding of how much the new imaging techniques impacted the recent advances in parasite biology, especially the immunobiology of protozoan parasites.
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Affiliation(s)
- Mohammed A. Afifi
- Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Medical Parasitology, Faculty of Medicine, Beni-Suef University, Beni-Suef, Egypt
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17
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Egarter S, Santos JM, Kehrer J, Sattler J, Frischknecht F, Mair GR. Gliding motility protein LIMP promotes optimal mosquito midgut traversal and infection by Plasmodium berghei. Mol Biochem Parasitol 2021; 241:111347. [PMID: 33347893 PMCID: PMC7856051 DOI: 10.1016/j.molbiopara.2020.111347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 12/02/2022]
Abstract
Substrate-dependent gliding motility is key to malaria transmission. It mediates host cell traversal, invasion and infection by Plasmodium and related apicomplexan parasites. The 110 amino acid-long cell surface protein LIMP is essential for P. berghei sporozoites where it is required for the invasion of the mosquito's salivary glands and the liver cells of the rodent host. Here we define an additional role for LIMP during mosquito invasion by the ookinete. limp mRNA is provided as a translationally repressed mRNP (messenger ribonucleoprotein) by the female gametocyte and the protein translated in the ookinete. Parasites depleted of limp (Δlimp) develop ookinetes with apparent normal morphology and no defect during in vitro gliding motility, and yet display a pronounced reduction in oocyst numbers; compared to wildtype 82 % more Δlimp ookinetes remain within the mosquito blood meal explaining the decrease in oocysts. As in the sporozoite, LIMP exerts a profound role on ookinete infection of the mosquito.
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Affiliation(s)
- Saskia Egarter
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Jorge M Santos
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal
| | - Jessica Kehrer
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Julia Sattler
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Friedrich Frischknecht
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Gunnar R Mair
- Parasitology, Department of Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina da Universidade de Lisboa, Edifício Egas Moniz, Av. Prof. Egas Moniz, Lisbon, Portugal; Iowa State University, Biomedical Sciences, Ames, IA, United States.
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18
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Recio-Tótoro B, Condé R, Claudio-Piedras F, Lanz-Mendoza H. Affinity purification of Plasmodium ookinetes from in vitro cultures using extracellular matrix gel. Parasitol Int 2020; 80:102242. [PMID: 33152548 DOI: 10.1016/j.parint.2020.102242] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 10/19/2020] [Accepted: 10/31/2020] [Indexed: 12/26/2022]
Abstract
Malaria transmission depends on the parasites' successful invasion of the mosquito. This is achieved by the ookinete, a motile zygote that forms in the blood bolus after the mosquito takes an infectious blood meal. The ookinete invades the midgut epithelium and strongly attaches to the basal lamina, differentiating into an oocyst that produces the vertebrate-invasive sporozoites. Despite their importance, the ookinete and the oocyst are the least studied stages of the parasite. Much of what we know about the ookinete comes from in vitro experiments, which are hindered by the concomitant contamination with blood cells and other parasite stages. Although methods to purify them exist, they vary in terms of yield, costs, and difficulty to perform. A method for ookinete purification taking advantage of their adhesive properties was herein developed. The method consists of covering any culture-suitable surface with extracellular matrix gel, after which the ookinete culture is incubated on the gel to allow for ookinete attachment. The contaminant cells are then simply washed away. This procedure results in purer and less stressed ookinete preparations, which, by the nature of the method, are ready for oocyst production. Furthermore, it allows for micro-purifications using only 1 μl of blood, opening the possibility to make axenic ookinete cultures without sacrificing mice.
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Affiliation(s)
- Benito Recio-Tótoro
- Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, 62100 Cuernavaca, Morelos, Mexico; Instituto de Biotecnología, Universidad Nacional Autónoma de México, 62210 Cuernavaca, Morelos, Mexico
| | - Renaud Condé
- Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, 62100 Cuernavaca, Morelos, Mexico
| | - Fabiola Claudio-Piedras
- Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, 62100 Cuernavaca, Morelos, Mexico
| | - Humberto Lanz-Mendoza
- Centro de Investigaciones Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, 62100 Cuernavaca, Morelos, Mexico.
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19
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The Riveting Cellular Structures of Apicomplexan Parasites. Trends Parasitol 2020; 36:979-991. [PMID: 33011071 DOI: 10.1016/j.pt.2020.09.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/31/2020] [Accepted: 09/03/2020] [Indexed: 12/21/2022]
Abstract
Parasitic protozoa of the phylum Apicomplexa cause a range of human and animal diseases. Their complex life cycles - often heteroxenous with sexual and asexual phases in different hosts - rely on elaborate cytoskeletal structures to enable morphogenesis and motility, organize cell division, and withstand diverse environmental forces. This review primarily focuses on studies using Toxoplasma gondii and Plasmodium spp. as the best studied apicomplexans; however, many cytoskeletal adaptations are broadly conserved and predate the emergence of the parasitic phylum. After decades cataloguing the constituents of such structures, a dynamic picture is emerging of the assembly and maintenance of apicomplexan cytoskeletons, illuminating how they template and orient critical processes during infection. These observations impact our view of eukaryotic diversity and offer future challenges for cell biology.
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20
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Volohonsky G, Paul-Gilloteaux P, Štáfková J, Soichot J, Salamero J, Levashina EA. Kinetics of Plasmodium midgut invasion in Anopheles mosquitoes. PLoS Pathog 2020; 16:e1008739. [PMID: 32946522 PMCID: PMC7526910 DOI: 10.1371/journal.ppat.1008739] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 09/30/2020] [Accepted: 06/23/2020] [Indexed: 01/06/2023] Open
Abstract
Malaria-causing Plasmodium parasites traverse the mosquito midgut cells to establish infection at the basal side of the midgut. This dynamic process is a determinant of mosquito vector competence, yet the kinetics of the parasite migration is not well understood. Here we used transgenic mosquitoes of two Anopheles species and a Plasmodium berghei fluorescence reporter line to track parasite passage through the mosquito tissues at high spatial resolution. We provide new quantitative insight into malaria parasite invasion in African and Indian Anopheles species and propose that the mosquito complement-like system contributes to the species-specific dynamics of Plasmodium invasion. The traversal of the mosquito midgut cells is one of the critical stages in the life cycle of malaria parasites. Motile parasite forms, called ookinetes, traverse the midgut epithelium in a dynamic process which is not fully understood. Here, we harnessed transgenic reporters to track invasion of Plasmodium parasites in African and Indian mosquito species. We found important differences in parasite dynamics between the two Anopheles species and demonstrated a role of the mosquito complement-like system in regulation of parasite invasion of the midgut cells.
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Affiliation(s)
- Gloria Volohonsky
- INSERM U963, CNRS UPR9022, University of Strasbourg, Strasbourg, France
| | - Perrine Paul-Gilloteaux
- SERPICO Inria Team/CNRS UMR 144, Institut Curie, Paris, France.,National Biology and Health Infrastructure "France Bioimaging", Institut Curie, Paris, France.,Cell and Tissue Imaging Facility, IBiSA, Institut Curie, Paris, France
| | - Jitka Štáfková
- INSERM U963, CNRS UPR9022, University of Strasbourg, Strasbourg, France
| | - Julien Soichot
- INSERM U963, CNRS UPR9022, University of Strasbourg, Strasbourg, France
| | - Jean Salamero
- SERPICO Inria Team/CNRS UMR 144, Institut Curie, Paris, France.,National Biology and Health Infrastructure "France Bioimaging", Institut Curie, Paris, France.,Cell and Tissue Imaging Facility, IBiSA, Institut Curie, Paris, France
| | - Elena A Levashina
- INSERM U963, CNRS UPR9022, University of Strasbourg, Strasbourg, France.,Vector Biology Unit, Max Planck Institute for Infection Biology, Berlin, Germany
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21
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Abstract
The mosquito midgut is a critical barrier that Plasmodium parasites must overcome to complete their developmental cycle and be transmitted to a new vertebrate host. Previous confocal studies with fixed infected midguts showed that ookinetes traverse midgut epithelial cells and cause irreversible tissue damage. Here, we investigated the spatiotemporal dynamics of ookinete midgut traversal and the response of midgut cells to invasion. A novel mounting strategy was established, suitable fluorescent dye combinations were identified and protocols optimized to label mosquito tissues in vivo, and live imaging protocols using confocal microscopy were developed. Tracking data showed that ookinetes gliding on the midgut surface travel faster and farther than those that remain in the lumen or those that have invaded the epithelium. Image analysis confirmed that parasite invasion and cell traversal occur within a couple of minutes, while caspase activity in damaged cells, indicative of cellular apoptosis, and F-actin cytoskeletal rearrangements in cells extruded into the gut lumen persist for several hours. This temporal difference highlights the importance of hemocyte-mediated cellular immunity and the mosquito complement system to mount a coordinated and effective antiplasmodial response. This novel in vivo imaging protocol allowed us to continuously observe individual ookinetes in live mosquitoes within the gut lumen and during cell traversal and to capture the subsequent cellular responses to invasion in real time for several hours, without loss of tissue integrity.IMPORTANCE Malaria is one of the most devastating parasitic diseases in humans and is transmitted by anopheline mosquitoes. The mosquito midgut is a critical barrier that Plasmodium parasites must overcome to complete their developmental cycle and be transmitted to a new host. Here, we developed a new strategy to visualize Plasmodium ookinetes as they traverse the mosquito midgut and to follow the response of damaged epithelial cells by imaging live mosquitoes. Understanding the spatial and temporal aspects of these interactions is critical when developing novel strategies to disrupt disease transmission.
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Heparin Administered to Anopheles in Membrane Feeding Assays Blocks Plasmodium Development in the Mosquito. Biomolecules 2020; 10:biom10081136. [PMID: 32752200 PMCID: PMC7463908 DOI: 10.3390/biom10081136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/16/2020] [Accepted: 07/29/2020] [Indexed: 12/15/2022] Open
Abstract
Innovative antimalarial strategies are urgently needed given the alarming evolution of resistance to every single drug developed against Plasmodium parasites. The sulfated glycosaminoglycan heparin has been delivered in membrane feeding assays together with Plasmodium berghei-infected blood to Anopheles stephensi mosquitoes. The transition between ookinete and oocyst pathogen stages in the mosquito has been studied in vivo through oocyst counting in dissected insect midguts, whereas ookinete interactions with heparin have been followed ex vivo by flow cytometry. Heparin interferes with the parasite's ookinete-oocyst transition by binding ookinetes, but it does not affect fertilization. Hypersulfated heparin is a more efficient blocker of ookinete development than native heparin, significantly reducing the number of oocysts per midgut when offered to mosquitoes at 5 µg/mL in membrane feeding assays. Direct delivery of heparin to mosquitoes might represent a new antimalarial strategy of rapid implementation, since it would not require clinical trials for its immediate deployment.
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Soré H, Lopatriello A, Ebstie YA, Tenoh Guedoung AR, Hilou A, Pereira JA, Kijjoa A, Habluetzel A, Taglialatela-Scafati O. Plasmodium stage-selective antimalarials from Lophira lanceolata stem bark. PHYTOCHEMISTRY 2020; 174:112336. [PMID: 32192964 DOI: 10.1016/j.phytochem.2020.112336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/26/2020] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Targeting the transmissible stages of the Plasmodium parasite that develop in the human and mosquito host is a crucial strategy for malaria control and elimination. Medicinal plants offer a prolific source for the discovery of new antimalarial compounds. The recent identification of the gametocytocidal activity of lophirone E, obtained from the African plant Lophira lanceolata (Ochnaceae), inspired the evaluation of the plant also against early sporogonic stages of the parasite development. The bioassay-guided phytochemical study led to the isolation of two known lanceolins and of a new glycosylated bichalcone, named glucolophirone C. Its stereostructure, including absolute configuration of the bichalcone moiety, was elucidated by means of NMR, HRMS, ECD and computational calculations. Lanceolin B proved to be a potent inhibitor of the development of Plasmodium early sporogonic stages indicating that the plant produces two different stage-specific antimalarial agents acting on transmissible stages in the human and mosquito host.
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Affiliation(s)
- Harouna Soré
- Centre National de Recherche et de Formation sur le Paludisme, Ouagadougou, 01 BP 2208, Burkina Faso; Laboratoire de Biochimie et Chimie Appliquées (LABIOCA), Université Joseph Ki Zerbo de Ouagadougou, 03 BP: 7021, Burkina Faso
| | - Annalisa Lopatriello
- Department of Pharmacy, School of Medicine and Surgery, University of Naples Federico II, Via D. Montesano 49, 80131, Naples, Italy
| | - Yehenew A Ebstie
- Scuola di Scienze del Farmaco e dei Prodotti della Salute, Università di Camerino Macerata, Via Madonna delle Carceri 9, 62032, Camerino, Italy
| | - Alain R Tenoh Guedoung
- Scuola di Scienze del Farmaco e dei Prodotti della Salute, Università di Camerino Macerata, Via Madonna delle Carceri 9, 62032, Camerino, Italy
| | - Adama Hilou
- Laboratoire de Biochimie et Chimie Appliquées (LABIOCA), Université Joseph Ki Zerbo de Ouagadougou, 03 BP: 7021, Burkina Faso
| | - José A Pereira
- ICBAS-Instituto de Ciencias Biomedicas Abel Salazar and CIIMAR, Rua de Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Anake Kijjoa
- ICBAS-Instituto de Ciencias Biomedicas Abel Salazar and CIIMAR, Rua de Jorge Viterbo Ferreira, 228, 4050-313, Porto, Portugal
| | - Annette Habluetzel
- Scuola di Scienze del Farmaco e dei Prodotti della Salute, Università di Camerino Macerata, Via Madonna delle Carceri 9, 62032, Camerino, Italy; Centro Interuniversitario di Ricerca Sulla Malaria / Italian Malaria Network, University of Milan, Milan, Italy.
| | - Orazio Taglialatela-Scafati
- Department of Pharmacy, School of Medicine and Surgery, University of Naples Federico II, Via D. Montesano 49, 80131, Naples, Italy; Centro Interuniversitario di Ricerca Sulla Malaria / Italian Malaria Network, University of Milan, Milan, Italy.
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24
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Detection of Protein Aggregation in Live Plasmodium Parasites. Antimicrob Agents Chemother 2020; 64:AAC.02135-19. [PMID: 32284383 DOI: 10.1128/aac.02135-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 04/06/2020] [Indexed: 02/08/2023] Open
Abstract
The rapid evolution of resistance in the malaria parasite to every single drug developed against it calls for the urgent identification of new molecular targets. Using a stain specific for the detection of intracellular amyloid deposits in live cells, we have detected the presence of abundant protein aggregates in Plasmodium falciparum blood stages and female gametes cultured in vitro, in the blood stages of mice infected by Plasmodium yoelii, and in the mosquito stages of the murine malaria species Plasmodium berghei Aggregated proteins could not be detected in early rings, the parasite form that starts the intraerythrocytic cycle. A proteomics approach was used to pinpoint actual aggregating polypeptides in functional P. falciparum blood stages, which resulted in the identification of 369 proteins, with roles particularly enriched in nuclear import-related processes. Five aggregation-prone short peptides selected from this protein pool exhibited different aggregation propensity according to Thioflavin-T fluorescence measurements, and were observed to form amorphous aggregates and amyloid fibrils in transmission electron microscope images. The results presented suggest that generalized protein aggregation might have a functional role in malaria parasites. Future antimalarial strategies based on the upsetting of the pathogen's proteostasis and therefore affecting multiple gene products could represent the entry to new therapeutic approaches.
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25
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King JG. Developmental and comparative perspectives on mosquito immunity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 103:103458. [PMID: 31377103 DOI: 10.1016/j.dci.2019.103458] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 07/30/2019] [Accepted: 07/30/2019] [Indexed: 06/10/2023]
Abstract
Diseases spread by mosquitoes have killed more people than those spread by any other group of arthropod vectors and remain an important factor in determining global health and economic stability. The mosquito innate immune system can act to either modulate infection with human pathogens or fight off entomopathogens and increase the fitness and longevity of infected mosquitoes. While work remains towards understanding the larval immune system and the development of the mosquito immune system, it has recently become clearer that environmental factors heavily shape the developing mosquito immune system and continue to influence the adult immune system as well. The adult immune system has been well-studied and is known to involve multiple tissues and diverse molecular mechanisms. This review summarizes and synthesizes what is currently understood about the development of the mosquito immune system and includes comparisons of immune components unique to mosquitoes among the blood-feeding arthropods as well as important distinguishing factors between the anopheline and culicine mosquitoes. An explanation is included for how mosquito immunity factors into vector competence and vectorial capacity is presented along with a model for the interrelationships between nutrition, microbiome, pathogen interactions and behavior as they relate to mosquito development, immune status, adult female fitness and ultimately, vectorial capacity. Novel discoveries in the fields of mosquito ecoimmunology, neuroimmunology, and intracellular antiviral responses are highlighted.
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Affiliation(s)
- Jonas G King
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, 32 Creelman Street, Dorman 402, Mississippi State, MS 39762, USA.
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26
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Delves M, Lafuente-Monasterio MJ, Upton L, Ruecker A, Leroy D, Gamo FJ, Sinden R. Fueling Open Innovation for Malaria Transmission-Blocking Drugs: Hundreds of Molecules Targeting Early Parasite Mosquito Stages. Front Microbiol 2019; 10:2134. [PMID: 31572339 PMCID: PMC6753678 DOI: 10.3389/fmicb.2019.02134] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 08/30/2019] [Indexed: 11/13/2022] Open
Abstract
Background Despite recent successes at controlling malaria, progress has stalled with an estimated 219 million cases and 435,000 deaths in 2017 alone. Combined with emerging resistance to front line antimalarial therapies in Southeast Asia, there is an urgent need for new treatment options and novel approaches to halt the spread of malaria. Plasmodium, the parasite responsible for malaria propagates through mosquito transmission. This imposes an acute bottleneck on the parasite population and transmission-blocking interventions exploiting this vulnerability are recognized as vital for malaria elimination. Methods 13,533 small molecules with known activity against Plasmodium falciparum asexual parasites were screened for additional transmission-blocking activity in an ex vivo Plasmodium berghei ookinete development assay. Active molecules were then counterscreened in dose response against HepG2 cells to determine their activity/cytotoxicity window and selected non-toxic representative molecules were fully profiled in a range of transmission and mosquito infection assays. Furthermore, the entire dataset was compared to other published screens of the same molecules against P. falciparum gametocytes and female gametogenesis. Results 437 molecules inhibited P. berghei ookinete formation with an IC50 < 10 μM. of which 273 showed >10-fold parasite selectivity compared to activity against HepG2 cells. Active molecules grouped into 49 chemical clusters of three or more molecules, with 25 doublets and 94 singletons. Six molecules representing six major chemical scaffolds confirmed their transmission-blocking activity against P. falciparum male and female gametocytes and inhibited P. berghei oocyst formation in the standard membrane feeding assay at 1 μM. When screening data in the P. berghei development ookinete assay was compared to published screens of the same library in assays against P. falciparum gametocytes and female gametogenesis, it was established that each assay identified distinct, but partially overlapping subsets of transmission-blocking molecules. However, selected molecules unique to each assay show transmission-blocking activity in mosquito transmission assays. Conclusion The P. berghei ookinete development assay is an excellent high throughput assay for efficiently identifying antimalarial molecules targeting early mosquito stage parasite development. Currently no high throughput transmission-blocking assay is capable of identifying all transmission-blocking molecules.
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Affiliation(s)
- Michael Delves
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom.,Department of Life Sciences, Imperial College London, London, United Kingdom
| | | | - Leanna Upton
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Andrea Ruecker
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland
| | | | - Robert Sinden
- Department of Life Sciences, Imperial College London, London, United Kingdom
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27
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Cappelli A, Valzano M, Cecarini V, Bozic J, Rossi P, Mensah P, Amantini C, Favia G, Ricci I. Killer yeasts exert anti-plasmodial activities against the malaria parasite Plasmodium berghei in the vector mosquito Anopheles stephensi and in mice. Parasit Vectors 2019; 12:329. [PMID: 31266522 PMCID: PMC6604151 DOI: 10.1186/s13071-019-3587-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 06/27/2019] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Wickerhamomyces anomalus is a yeast associated with different insects including mosquitoes, where it is proposed to be involved in symbiotic relationships with hosts. Different symbiotic strains of W. anomalus display a killer phenotype mediated by protein toxins with broad-spectrum antimicrobial activities. In particular, a killer toxin purified from a W. anomalus strain (WaF17.12), previously isolated from the malaria vector mosquito Anopheles stephensi, has shown strong in vitro anti-plasmodial activity against early sporogonic stages of the murine malaria parasite Plasmodium berghei. RESULTS Here, we provide evidence that WaF17.12 cultures, properly stimulated to induce the expression of the killer toxin, can directly affect in vitro P. berghei early sporogonic stages, causing membrane damage and parasite death. Moreover, we demonstrated by in vivo studies that mosquito dietary supplementation with activated WaF17.12 cells interfere with ookinete development in the midgut of An. stephensi. Besides the anti-sporogonic action of WaF17.12, an inhibitory effect of purified WaF17.12-killer toxin was observed on erythrocytic stages of P. berghei, with a consequent reduction of parasitaemia in mice. The preliminary safety tests on murine cell lines showed no side effects. CONCLUSIONS Our findings demonstrate the anti-plasmodial activity of WaF17.12 against different developmental stages of P. berghei. New studies on P. falciparum are needed to evaluate the use of killer yeasts as innovative tools in the symbiotic control of malaria.
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Affiliation(s)
- Alessia Cappelli
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Matteo Valzano
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Valentina Cecarini
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Jovana Bozic
- Florida Medical Entomology Laboratory, University of Florida, Vero Beach, FL, USA
| | - Paolo Rossi
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Priscilla Mensah
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Consuelo Amantini
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Guido Favia
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Irene Ricci
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy.
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28
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Santana RAG, Oliveira MC, Cabral I, Junior RCAS, de Sousa DRT, Ferreira L, Lacerda MVG, Monteiro WM, Abrantes P, Guerra MDGVB, Silveira H. Anopheles aquasalis transcriptome reveals autophagic responses to Plasmodium vivax midgut invasion. Parasit Vectors 2019; 12:261. [PMID: 31126324 PMCID: PMC6534896 DOI: 10.1186/s13071-019-3506-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 05/14/2019] [Indexed: 01/23/2023] Open
Abstract
Background Elimination of malaria depends on mastering transmission and understanding the biological basis of Plasmodium infection in the vector. The first mosquito organ to interact with the parasite is the midgut and its transcriptomic characterization during infection can reveal effective antiplasmodial responses able to limit the survival of the parasite. The vector response to Plasmodium vivax is not fully characterized, and its specificities when compared with other malaria parasites can be of fundamental interest for specific control measures. Methods Experimental infections were performed using a membrane-feeding device. Three groups were used: P. vivax-blood-fed, blood-fed on inactivated gametocytes, and unfed mosquitoes. Twenty-four hours after feeding, the mosquitoes were dissected and the midgut collected for transcriptomic analysis using RNAseq. Nine cDNA libraries were generated and sequenced on an Illumina HiSeq2500. Readings were checked for quality control and analysed using the Trinity platform for de novo transcriptome assembly. Transcript quantification was performed and the transcriptome was functionally annotated. Differential expression gene analysis was carried out. The role of the identified mechanisms was further explored using functional approaches. Results Forty-nine genes were identified as being differentially expressed with P. vivax infection: 34 were upregulated and 15 were downregulated. Half of the P. vivax-related differentially expressed genes could be related to autophagy; therefore, the effect of the known inhibitor (wortmannin) and activator (spermidine) was tested on the infection outcome. Autophagic activation significantly reduced the intensity and prevalence of infection. This was associated with transcription alterations of the autophagy regulating genes Beclin, DRAM and Apg8. Conclusions Our data indicate that P. vivax invasion of An. aquasalis midgut epithelium triggers an autophagic response and its activation reduces infection. This suggests a novel mechanism that mosquitoes can use to fight Plasmodium infection. Electronic supplementary material The online version of this article (10.1186/s13071-019-3506-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rosa Amélia Gonçalves Santana
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Maurício Costa Oliveira
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Iria Cabral
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Rubens Celso Andrade Silva Junior
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Débora Raysa Teixeira de Sousa
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Lucas Ferreira
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Marcus Vinícius Guimarães Lacerda
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil.,Instituto Leônidas & Maria Deane, Fundação Oswaldo Cruz, Manaus, Brazil
| | - Wuelton Marcelo Monteiro
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Patrícia Abrantes
- Instituto de Higiene e Medicina Tropical, Global Health and Tropical Medicine, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Maria das Graças Vale Barbosa Guerra
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil
| | - Henrique Silveira
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Brazil. .,Instituto de Higiene e Medicina Tropical, Global Health and Tropical Medicine, Universidade Nova de Lisboa, Lisboa, Portugal.
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29
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McCaffery JN, Fonseca JA, Singh B, Cabrera-Mora M, Bohannon C, Jacob J, Arévalo-Herrera M, Moreno A. A Multi-Stage Plasmodium vivax Malaria Vaccine Candidate Able to Induce Long-Lived Antibody Responses Against Blood Stage Parasites and Robust Transmission-Blocking Activity. Front Cell Infect Microbiol 2019; 9:135. [PMID: 31119106 PMCID: PMC6504793 DOI: 10.3389/fcimb.2019.00135] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/15/2019] [Indexed: 12/13/2022] Open
Abstract
Malaria control and interventions including long-lasting insecticide-treated nets, indoor residual spraying, and intermittent preventative treatment in pregnancy have resulted in a significant reduction in the number of Plasmodium falciparum cases. Considerable efforts have been devoted to P. falciparum vaccines development with much less to P. vivax. Transmission-blocking vaccines, which can elicit antibodies targeting Plasmodium antigens expressed during sexual stage development and interrupt transmission, offer an alternative strategy to achieve malaria control. The post-fertilization antigen P25 mediates several functions essential to ookinete survival but is poorly immunogenic in humans. Previous clinical trials targeting this antigen have suggested that conjugation to a carrier protein could improve the immunogenicity of P25. Here we report the production, and characterization of a vaccine candidate composed of a chimeric P. vivax Merozoite Surface Protein 1 (cPvMSP1) genetically fused to P. vivax P25 (Pvs25) designed to enhance CD4+ T cell responses and its assessment in a murine model. We demonstrate that antibodies elicited by immunization with this chimeric protein recognize both the erythrocytic and sexual stages and are able to block the transmission of P. vivax field isolates in direct membrane-feeding assays. These findings provide support for the continued development of multi-stage transmission blocking vaccines targeting the life-cycle stage responsible for clinical disease and the sexual-stage development accountable for disease transmission simultaneously.
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Affiliation(s)
- Jessica N. McCaffery
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
| | - Jairo A. Fonseca
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, GA, United States
| | - Balwan Singh
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
| | - Monica Cabrera-Mora
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
| | - Caitlin Bohannon
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
| | - Joshy Jacob
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, United States
| | - Myriam Arévalo-Herrera
- Caucaseco Scientific Research Center, Malaria Vaccine and Drug Development Center, Cali, Colombia
| | - Alberto Moreno
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, United States
- Division of Infectious Diseases, Department of Medicine, Emory University, Atlanta, GA, United States
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30
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Diaz-Albiter HM, Regnault C, Alpizar-Sosa EA, McGuinness D, Barrett M, Dillon RJ. Non-invasive visualisation and identification of fluorescent Leishmania tarentolae in infected sand flies. Wellcome Open Res 2018; 3:160. [PMID: 30756095 PMCID: PMC6367660 DOI: 10.12688/wellcomeopenres.14910.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2018] [Indexed: 12/01/2022] Open
Abstract
Background: The leishmaniases are neglected diseases that affect some of the most vulnerable populations in the tropical and sub-tropical world. The parasites are transmitted by sand flies and novel strategies to control this neglected vector-borne disease are needed. Blocking transmission by targeting the parasite inside the phlebotomine vector offers potential in this regard. Some experimental approaches can be best performed by longitudinal study of parasites within flies, for which non-destructive methods to identify infected flies and to follow parasite population changes are required. Methods: Lutzomyia longipalpis were reared under standard insectary conditions at the Wellcome Centre for Molecular Parasitology. Flies were artificially infected with L. tarentolae expressing green fluorescent protein (GFP. Parasite counts were carried out 5 days post-infection and the percentage of infected flies and survival of infected females was established up to days 5 post-infection. Whole living females were visualised using an epifluorescence inverted microscope to detect the presence parasites inferred by a localised green fluorescent region in the upper thorax. Confirmation of infection was performed by localised-fluorescence of dissected flies and estimates of the parasite population. Results : Leishmania tarentolae was successfully transfected and expressed GFP in vitro. L. tarentolae-GFP Infected flies showed similar parasite populations when compared to non-transfected parasites ( L. tarentolae-WT). Survival of non-infected females was higher than L. tarentolae-infected groups, (Log-rank (Mantel-Cox) test, p<0.05). L. tarentolae-GFP infected females displayed an intense localised fluorescence in the thorax while other specimens from the same infected group did not. Localised fluorescent flies were dissected and showed higher parasite populations compared to those that did not demonstrate high concentrations in this region (t-test, p<0.005). Conclusion : These results demonstrate the feasibility of establishing a safe non-human infectious fluorescent Leishmania-sand fly infection model by allowing non-destructive imaging to signal the establishment of Leishmania infections in living sand flies.
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Affiliation(s)
- Hector M. Diaz-Albiter
- El Colegio de la Frontera Sur, Villahermosa, Tabasco, 86280, Mexico
- Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow, G12 8TA, UK
| | - Clément Regnault
- Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow, G12 8TA, UK
| | | | - Dagmara McGuinness
- Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow, G12 8TA, UK
| | - Michael Barrett
- Wellcome Centre for Molecular Parasitology, University of Glasgow, Glasgow, G12 8TA, UK
| | - Rod J. Dillon
- Faculty of Health and Medicine, Lancaster University, Lancaster, Lancashire, LA1 4YQ, UK
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31
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Delves MJ, Miguel-Blanco C, Matthews H, Molina I, Ruecker A, Yahiya S, Straschil U, Abraham M, León ML, Fischer OJ, Rueda-Zubiaurre A, Brandt JR, Cortés Á, Barnard A, Fuchter MJ, Calderón F, Winzeler EA, Sinden RE, Herreros E, Gamo FJ, Baum J. A high throughput screen for next-generation leads targeting malaria parasite transmission. Nat Commun 2018; 9:3805. [PMID: 30228275 PMCID: PMC6143625 DOI: 10.1038/s41467-018-05777-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/26/2018] [Indexed: 01/22/2023] Open
Abstract
Spread of parasite resistance to artemisinin threatens current frontline antimalarial therapies, highlighting the need for new drugs with alternative modes of action. Since only 0.2–1% of asexual parasites differentiate into sexual, transmission-competent forms, targeting this natural bottleneck provides a tangible route to interrupt disease transmission and mitigate resistance selection. Here we present a high-throughput screen of gametogenesis against a ~70,000 compound diversity library, identifying seventeen drug-like molecules that target transmission. Hit molecules possess varied activity profiles including male-specific, dual acting male–female and dual-asexual-sexual, with one promising N-((4-hydroxychroman-4-yl)methyl)-sulphonamide scaffold found to have sub-micromolar activity in vitro and in vivo efficacy. Development of leads with modes of action focussed on the sexual stages of malaria parasite development provide a previously unexplored base from which future therapeutics can be developed, capable of preventing parasite transmission through the population. Sexual forms of malaria parasites are responsible for transmission to the mosquito. Anti-malarial drug resistance remains a serious problem and requires advent of new drug therapies. Here, the authors present a high-throughput screen of potential antimalarial compounds, identifying seventeen drug-like molecules specifically targeting transmission.
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Affiliation(s)
- Michael J Delves
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Celia Miguel-Blanco
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK.,Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Holly Matthews
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Irene Molina
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Andrea Ruecker
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Sabrina Yahiya
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Ursula Straschil
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Matthew Abraham
- School of Medicine, University of California San Diego, 9500 Gilman Drive 0760, La Jolla, CA, 92093, USA
| | - María Luisa León
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Oliver J Fischer
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Ainoa Rueda-Zubiaurre
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Jochen R Brandt
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Álvaro Cortés
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Anna Barnard
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Matthew J Fuchter
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Félix Calderón
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Elizabeth A Winzeler
- School of Medicine, University of California San Diego, 9500 Gilman Drive 0760, La Jolla, CA, 92093, USA
| | - Robert E Sinden
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK
| | - Esperanza Herreros
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain
| | - Francisco J Gamo
- Diseases of the Developing World (DDW), GlaxoSmithKline, 28760, Tres Cantos, Madrid, Spain.
| | - Jake Baum
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, Exhibition Road, South Kensington, London, SW7 2AZ, UK.
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Deligianni E, Silmon de Monerri NC, McMillan PJ, Bertuccini L, Superti F, Manola M, Spanos L, Louis C, Blackman MJ, Tilley L, Siden-Kiamos I. Essential role of Plasmodium perforin-like protein 4 in ookinete midgut passage. PLoS One 2018; 13:e0201651. [PMID: 30102727 PMCID: PMC6089593 DOI: 10.1371/journal.pone.0201651] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 07/19/2018] [Indexed: 01/22/2023] Open
Abstract
Pore forming proteins such as those belonging to the membrane attack/perforin (MACPF) family have important functions in many organisms. Of the five MACPF proteins found in Plasmodium parasites, three have functions in cell passage and one in host cell egress. Here we report an analysis of the perforin-like protein 4, PPLP4, in the rodent parasite Plasmodium berghei. We found that the protein is expressed only in the ookinete, the invasive stage of the parasite formed in the mosquito midgut. Transcriptional analysis revealed that expression of the pplp4 gene commences during ookinete development. The protein was detected in retorts and mature ookinetes. Using two antibodies, the protein was found localized in a dotted pattern, and 3-D SIM super-resolution microcopy revealed the protein in the periphery of the cell. Analysis of a C-terminal mCherry fusion of the protein however showed mainly cytoplasmic label. A pplp4 null mutant formed motile ookinetes, but these were unable to invade and traverse the midgut epithelium resulting in severely impaired oocyst formation and no transmission to naïve mice. However, when in vitro cultured ookinetes were injected into the thorax of the mosquito, thus by-passing midgut passage, sporozoites were formed and the mutant parasites were able to infect naïve mice. Taken together, our data show that PPLP4 is required only for ookinete invasion of the mosquito midgut. Thus PPLP4 has a similar role to the previously studied PPLP3 and PPLP5, raising the question why three proteins with MACPF domains are needed for invasion by the ookinete of the mosquito midgut epithelium.
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Affiliation(s)
- Elena Deligianni
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
- * E-mail:
| | | | - Paul J. McMillan
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia
- ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
- Biological Optical Microcopy Platform, The University of Melbourne, Melbourne, VIC, Australia
| | - Lucia Bertuccini
- National Centre for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Fabiana Superti
- National Centre for Innovative Technologies in Public Health, National Institute of Health, Rome, Italy
| | - Maria Manola
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Lefteris Spanos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Christos Louis
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
| | - Michael J. Blackman
- The Francis Crick Institute, London, United Kingdom
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Melbourne, VIC, Australia
- ARC Centre of Excellence for Coherent X-ray Science, The University of Melbourne, Melbourne, VIC, Australia
- Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, Australia
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology—Hellas, Heraklion, Greece
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Goulielmaki E, Kaforou S, Venugopal K, Loukeris TG, Siden-Kiamos I, Koussis K. Distinct effects of HIV protease inhibitors and ERAD inhibitors on zygote to ookinete transition of the malaria parasite. Mol Biochem Parasitol 2018; 220:10-14. [DOI: 10.1016/j.molbiopara.2017.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 12/18/2017] [Accepted: 12/22/2017] [Indexed: 02/02/2023]
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Bartholomay LC, Michel K. Mosquito Immunobiology: The Intersection of Vector Health and Vector Competence. ANNUAL REVIEW OF ENTOMOLOGY 2018; 63:145-167. [PMID: 29324042 DOI: 10.1146/annurev-ento-010715-023530] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
As holometabolous insects that occupy distinct aquatic and terrestrial environments in larval and adult stages and utilize hematophagy for nutrient acquisition, mosquitoes are subjected to a wide variety of symbiotic interactions. Indeed, mosquitoes play host to endosymbiotic, entomopathogenic, and mosquito-borne organisms, including protozoa, viruses, bacteria, fungi, fungal-like organisms, and metazoans, all of which trigger and shape innate infection-response capacity. Depending on the infection or interaction, the mosquito may employ, for example, cellular and humoral immune effectors for septic infections in the hemocoel, humoral infection responses in the midgut lumen, and RNA interference and programmed cell death for intracellular pathogens. These responses often function in concert, regardless of the infection type, and provide a robust front to combat infection. Mosquito-borne pathogens and entomopathogens overcome these immune responses, employing avoidance or suppression strategies. Burgeoning methodologies are capitalizing on this concerted deployment of immune responses to control mosquito-borne disease.
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Affiliation(s)
- Lyric C Bartholomay
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Wisconsin 53706;
| | - Kristin Michel
- Division of Biology, Kansas State University, Manhattan, Kansas 66506;
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Curra C, McMillan PJ, Spanos L, Mollard V, Deligianni E, McFadden G, Tilley L, Siden-Kiamos I. Structured illumination microscopy reveals actin I localization in discreet foci in Plasmodium berghei gametocytes. Exp Parasitol 2017; 181:82-87. [PMID: 28803903 DOI: 10.1016/j.exppara.2017.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 06/30/2017] [Accepted: 08/08/2017] [Indexed: 11/26/2022]
Abstract
Actin has important roles in Plasmodium parasites but its exact function in different life stages is not yet fully elucidated. Here we report the localization of ubiquitous actin I in gametocytes of the rodent model parasite P. berghei. Using an antibody specifically recognizing F-actin and deconvolution microscopy we detected actin I in a punctate pattern in gametocytes. 3D-Structured Illumination Microscopy which allows sub-diffraction limit imaging resolved the signal into structures of less than 130 nm length. A portion of actin I was soluble, but the protein was also found complexed in a stabilized form which could only be completely solubilized by treatment with SDS. An additional population of actin was pelleted at 100 000 × g, consistent with F-actin. Our results suggest that actin in this non-motile form of the parasite is present in short filaments cross-linked to other structures in a cytoskeleton.
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Affiliation(s)
- Chiara Curra
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Paul J McMillan
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, 3051 VIC, Australia; Biological Optical Microscopy Platform, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Lefteris Spanos
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Vanessa Mollard
- School of BioSciences, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Elena Deligianni
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece
| | - Geoffrey McFadden
- School of BioSciences, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, 3051 VIC, Australia
| | - Inga Siden-Kiamos
- Institute of Molecular Biology and Biotechnology, FORTH, Heraklion, Greece.
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Plasmodium berghei PIMMS2 Promotes Ookinete Invasion of the Anopheles gambiae Mosquito Midgut. Infect Immun 2017; 85:IAI.00139-17. [PMID: 28559405 PMCID: PMC5520436 DOI: 10.1128/iai.00139-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/11/2017] [Indexed: 12/21/2022] Open
Abstract
Mosquito midgut stages of the malaria parasite present an attractive biological system to study host-parasite interactions and develop interventions to block disease transmission. Mosquito infection ensues upon oocyst development that follows ookinete invasion and traversal of the mosquito midgut epithelium. Here, we report the characterization of PIMMS2 (Plasmodium invasion of mosquito midgut screen candidate 2), a Plasmodium berghei protein with structural similarities to subtilisin-like proteins. PIMMS2 orthologs are present in the genomes of all plasmodia and are mapped between the subtilisin-encoding genes SUB1 and SUB3. P. berghei PIMMS2 is specifically expressed in zygotes and ookinetes and is localized on the ookinete surface. Loss of PIMMS2 function through gene disruption by homologous recombination leads to normal development of motile ookinetes that exhibit a severely impaired capacity to traverse the mosquito midgut and transform to oocysts. Genetic complementation of the disrupted locus with a mutated PIMMS2 allele reveals that amino acid residues corresponding to the putative subtilisin-like catalytic triad are important but not essential for protein function. Our data demonstrate that PIMMS2 is a novel ookinete-specific protein that promotes parasite traversal of the mosquito midgut epithelium and establishment of mosquito infection.
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Tardieux I, Baum J. Reassessing the mechanics of parasite motility and host-cell invasion. J Cell Biol 2017; 214:507-15. [PMID: 27573462 PMCID: PMC5004448 DOI: 10.1083/jcb.201605100] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 08/09/2016] [Indexed: 12/20/2022] Open
Abstract
The capacity to migrate is fundamental to multicellular and single-celled life. Apicomplexan parasites, an ancient protozoan clade that includes malaria parasites (Plasmodium) and Toxoplasma, achieve remarkable speeds of directional cell movement. This rapidity is achieved via a divergent actomyosin motor system, housed within a narrow compartment that lies underneath the length of the parasite plasma membrane. How this motor functions at a mechanistic level during motility and host cell invasion is a matter of debate. Here, we integrate old and new insights toward refining the current model for the function of this motor with the aim of revitalizing interest in the mechanics of how these deadly pathogens move.
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Affiliation(s)
- Isabelle Tardieux
- Institute of Advanced BioSciences, Institut National de la Santé et de la Recherche Médicale U1209, Centre National de la Recherche Scientifique UMR 5309, Université Grenoble Alpes, 38000, Grenoble, France
| | - Jake Baum
- Department of Life Sciences, Imperial College London, London SW7 2AZ, England, UK
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Moreau CA, Bhargav SP, Kumar H, Quadt KA, Piirainen H, Strauss L, Kehrer J, Streichfuss M, Spatz JP, Wade RC, Kursula I, Frischknecht F. A unique profilin-actin interface is important for malaria parasite motility. PLoS Pathog 2017; 13:e1006412. [PMID: 28552953 PMCID: PMC5464670 DOI: 10.1371/journal.ppat.1006412] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 06/08/2017] [Accepted: 05/16/2017] [Indexed: 11/30/2022] Open
Abstract
Profilin is an actin monomer binding protein that provides ATP-actin for incorporation into actin filaments. In contrast to higher eukaryotic cells with their large filamentous actin structures, apicomplexan parasites typically contain only short and highly dynamic microfilaments. In apicomplexans, profilin appears to be the main monomer-sequestering protein. Compared to classical profilins, apicomplexan profilins contain an additional arm-like β-hairpin motif, which we show here to be critically involved in actin binding. Through comparative analysis using two profilin mutants, we reveal this motif to be implicated in gliding motility of Plasmodium berghei sporozoites, the rapidly migrating forms of a rodent malaria parasite transmitted by mosquitoes. Force measurements on migrating sporozoites and molecular dynamics simulations indicate that the interaction between actin and profilin fine-tunes gliding motility. Our data suggest that evolutionary pressure to achieve efficient high-speed gliding has resulted in a unique profilin-actin interface in these parasites. The malaria parasite Plasmodium has two invasive forms that migrate across different tissue barriers, the ookinete and the very rapidly migrating sporozoite. Previous work has shown that the motility of these and related parasites (e.g. Toxoplasma gondii) depends on a highly dynamic actin cytoskeleton and retrograde flow of surface adhesins. These unusual actin dynamics are due to the divergent structure of protozoan actins and the actions of actin-binding proteins, which can have non-canonical functions in these parasites. Profilin is one of the most important and most investigated actin-binding proteins, which binds ADP-actin and catalyzes ADP-ATP exchange to then promote actin polymerization. Parasite profilins bind monomeric actin and contain an additional domain compared to canonical profilins. Here we show that this additional domain of profilin is critical for actin binding and rapid sporozoite motility but has little impact on the slower ookinete. Sporozoites of a parasite line carrying mutations in this domain cannot translate force production and retrograde flow into optimal parasite motility. Using molecular dynamics simulations, we find that differences between mutant parasites in their capacity to migrate can be traced back to a single hydrogen bond at the actin-profilin interface.
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Affiliation(s)
- Catherine A. Moreau
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Saligram P. Bhargav
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Hirdesh Kumar
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
| | - Katharina A. Quadt
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
| | - Henni Piirainen
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Léanne Strauss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Jessica Kehrer
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
| | - Martin Streichfuss
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
| | - Joachim P. Spatz
- Institute for Physical Chemistry, Biophysical Chemistry, Heidelberg University, Heidelberg, Germany
- Department of Cellular Biophysics, Max-Planck Institute for Medical Research, Heidelberg, Germany
| | - Rebecca C. Wade
- Molecular and Cellular Modeling Group, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance and Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University, Heidelberg, Germany
| | - Inari Kursula
- Biocenter Oulu and Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
- Department of Biomedicine, University of Bergen, Bergen, Norway
- * E-mail: (IK); (FF)
| | - Friedrich Frischknecht
- Integrative Parasitology, Center for Infectious Diseases, Heidelberg University Medical School, Heidelberg, Germany
- * E-mail: (IK); (FF)
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Pastrana-Mena R, Mathias DK, Delves M, Rajaram K, King JG, Yee R, Trucchi B, Verotta L, Dinglasan RR. A Malaria Transmission-Blocking (+)-Usnic Acid Derivative Prevents Plasmodium Zygote-to-Ookinete Maturation in the Mosquito Midgut. ACS Chem Biol 2016; 11:3461-3472. [PMID: 27978709 DOI: 10.1021/acschembio.6b00902] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The evolution of drug resistance is a recurrent problem that has plagued efforts to treat and control malaria. Recent emergence of artemisinin resistance in Southeast Asia underscores the need to develop novel antimalarials and identify new targetable pathways in Plasmodium parasites. Transmission-blocking approaches, which typically target gametocytes in the host bloodstream or parasite stages in the mosquito gut, are recognized collectively as a strategy that when used in combination with antimalarials that target erythrocytic stages will not only cure malaria but will also prevent subsequent transmission. We tested four derivatives of (+)-usnic acid, a metabolite isolated from lichens, for transmission-blocking activity against Plasmodium falciparum using the standard membrane feeding assay. For two of the derivatives, BT37 and BT122, we observed a consistent dose-response relationship between concentration in the blood meal and oocyst intensity in the midgut. To explore their mechanism of action, we used the murine model Plasmodium berghei and found that both derivatives prevent ookinete maturation. Using fluorescence microscopy, we demonstrated that in the presence of each compound zygote vitality was severely affected, and those that did survive failed to elongate and mature into ookinetes. The observed phenotypes were similar to those described for mutants of specific kinases (NEK2/NEK4) and of inner membrane complex 1 (IMC1) proteins, which are all vital to the zygote-to-ookinete transition. We discuss the implications of our findings and our high-throughput screening approach to identifying next generation, transmission-blocking antimalarials based on the scaffolds of these (+)-usnic acid derivatives.
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Affiliation(s)
- Rebecca Pastrana-Mena
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
| | - Derrick K. Mathias
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
| | - Michael Delves
- Department
of Life Sciences, Imperial College of London, London, United Kingdom
| | - Krithika Rajaram
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
| | - Jonas G. King
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
| | - Rebecca Yee
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
| | | | | | - Rhoel R. Dinglasan
- W.
Harry Feinstone Department of Molecular Microbiology and Immunology, Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States
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Dahiya N, Chianese G, Abay SM, Taglialatela-Scafati O, Esposito F, Lupidi G, Bramucci M, Quassinti L, Christophides G, Habluetzel A, Lucantoni L. In vitro and ex vivo activity of an Azadirachta indica A.Juss. seed kernel extract on early sporogonic development of Plasmodium in comparison with azadirachtin A, its most abundant constituent. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2016; 23:1743-1752. [PMID: 27912876 DOI: 10.1016/j.phymed.2016.10.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 10/12/2016] [Accepted: 10/26/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND NeemAzal® (NA) is a quantified extract from seed kernels of neem, Azadirachta indica A.Juss. (Meliaceae), with a wide spectrum of biological properties, classically ascribed to its limonoid content. NA contains several azadirachtins (A to L), azadirachtin A (AzaA) being its main constituent. AzaA has been shown to inhibit microgamete formation of the rodent malaria parasite Plasmodium berghei, and NA was found to completely inhibit the transmission of Plasmodium berghei to Anopheles stephensi mosquitoes when administered to gametocytemic mice at a corresponding AzaA dose of 50mg/kg before exposure to mosquitoes. PURPOSE The present study was aimed at i) assessing the pharmacodynamics and duration of action of NA and AzaA against P. berghei exflagellation in systemic circulation in mice and ii) elucidating the transmission blocking activity (TBA) of the main NA constituents. STUDY DESIGN The NA and AzaA pharmacodynamics on exflagellation were assessed through ex vivo exflagellation assays, while TBA of NA constituents was evaluated through in vitro ookinete development assay. METHODS Pharmacodynamics experiments: Peripheral blood from P. berghei infected BALB/c mice with circulating mature gametocytes, were treated i.p. with 50mg/kg and 100mg/kg pure AzaA and with NeemAzal® (Trifolio-M GmbH) at the corresponding AzaA concentrations. The effect magnitude and duration of action of compounds was estimated by counting exflagellation centers, formed by microgametocytes in process of releasing flagellated gametes, at various time points after treatment in ex vivo exflagellation tests. Ookinete Development Assay: The direct effects of NeemAzal® and AzaA on ookinete development were measured by fluorescence microscopy after incubation of gametocytemic blood with various concentrations of test substances in microplates for 24h. RESULTS The exflagellation tests revealed an half-life of NA anti-plasmodial compounds of up to 7h at a NA dose corresponding to 100mg/kg equivalent dose of AzaA. The ookinete development assay showed an increased activity of NA against early sporogonic stages compared to that of AzaA. The IC50 value determined for NA was 6.8µg/ml (CI95: 5.95-7.86), about half of the AzaA IC50 (12.4µg/ml; CI95: 11.0-14.04). CONCLUSION The stronger activity of NA, when compared to AzaA, could not be explained by an additive or synergistic effect by other azadirachtins (B, D and I) present in NA. In fact, the addition of these compounds at 50µM concentration to AzaA did not evidence any decrease of the IC50 against early sporogonic stages to that obtained with AzaA alone. It is likely that other non-limonoid compounds present in NA may contribute to AzaA activity and enhanced pharmacodynamics against exflagellation both in vitro and in vivo.
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Affiliation(s)
- Nisha Dahiya
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | - Giuseppina Chianese
- Department of Pharmacy, University of Naples Federico II, Via Montesano 49, 80131 Naples, Italy.
| | - Solomon Mequanente Abay
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy; School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | | | - Fulvio Esposito
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | - Giulio Lupidi
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | - Massimo Bramucci
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | - Luana Quassinti
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | | | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy.
| | - Leonardo Lucantoni
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, (MC) Italy; Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, 4111 Queensland, Australia.
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Tapanelli S, Habluetzel A, Pellei M, Marchiò L, Tombesi A, Capparè A, Santini C. Novel metalloantimalarials: Transmission blocking effects of water soluble Cu(I), Ag(I) and Au(I) phosphane complexes on the murine malaria parasite Plasmodium berghei. J Inorg Biochem 2016; 166:1-4. [PMID: 27815977 DOI: 10.1016/j.jinorgbio.2016.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/07/2016] [Accepted: 10/13/2016] [Indexed: 12/24/2022]
Abstract
The water soluble phosphane complexes [M(L)4]PF6 (M=Cu(I), Ag(I)) and [Au(L)4]Cl (L=thp (tris(hydroxymethyl)phosphane) or PTA (1,3,5-triaza-7-phosphaadamantane)) showed notable in vitro activity against Plasmodium early sporogonic stages, the sexual forms of the malaria parasite that are responsible for infection of the mosquito vector. Effects varied according to both, the type of metal and phosphane ligands. [Ag(thp)4]PF6 was the best performing complex exhibiting a half inhibitory concentration (IC50) value in the low micromolar range (0.3-15.6μM). The silver complex [Ag(thp)4]PF6 was characterized by X-ray crystallography revealing that the structure comprises the cationic complex [Ag(thp)4]+, the PF6- anion, and a water molecule of crystallization. Our results revealed that Cu(I), Ag(I) and Au(I) phosphanes complexes elicited similar activity profiles showing potential for the development of antimalarial, transmission blocking compounds. Molecules targeting the sexual parasite stages in the human and/or mosquito host are urgently needed to complement current artemisinin based treatments and next generation antimalarials in a vision not only to cure the disease but to interrupt its transmission.
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Affiliation(s)
- Sofia Tapanelli
- School of Pharmacy, University of Camerino, Piazza dei Costanti, Camerino, MC, Italy
| | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Piazza dei Costanti, Camerino, MC, Italy.
| | - Maura Pellei
- School of Science and Technology - Chemistry Division, University of Camerino, via S. Agostino 1, Camerino, MC, Italy.
| | - Luciano Marchiò
- Department of Chemistry, University of Parma, Parco Area delle Scienze 17A, Parma, Italy
| | - Alessia Tombesi
- School of Science and Technology - Chemistry Division, University of Camerino, via S. Agostino 1, Camerino, MC, Italy
| | - Ambra Capparè
- School of Science and Technology - Chemistry Division, University of Camerino, via S. Agostino 1, Camerino, MC, Italy
| | - Carlo Santini
- School of Science and Technology - Chemistry Division, University of Camerino, via S. Agostino 1, Camerino, MC, Italy
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42
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Tapanelli S, Chianese G, Lucantoni L, Yerbanga RS, Habluetzel A, Taglialatela-Scafati O. Transmission blocking effects of neem (Azadirachta indica) seed kernel limonoids on Plasmodium berghei early sporogonic development. Fitoterapia 2016; 114:122-126. [PMID: 27642038 DOI: 10.1016/j.fitote.2016.09.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 09/08/2016] [Accepted: 09/14/2016] [Indexed: 01/25/2023]
Abstract
Azadirachta indica, known as neem tree and traditionally called "nature's drug store" makes part of several African pharmacopeias and is widely used for the preparation of homemade remedies and commercial preparations against various illnesses, including malaria. Employing a bio-guided fractionation approach, molecules obtained from A. indica ripe and green fruit kernels were tested for activity against early sporogonic stages of Plasmodium berghei, the parasite stages that develop in the mosquito mid gut after an infective blood meal. The limonoid deacetylnimbin (3) was identified as one the most active compounds of the extract, with a considerably higher activity compared to that of the close analogue nimbin (2). Pure deacetylnimbin (3) appeared to interfere with transmissible Plasmodium stages at a similar potency as azadirachtin A. Considering its higher thermal and chemical stability, deacetylnimbin could represent a suitable alternative to azadirachtin A for the preparation of transmission blocking antimalarials.
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Affiliation(s)
- Sofia Tapanelli
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, MC, Italy
| | - Giuseppina Chianese
- Department of Pharmacy, University of Naples Federico II, Via Montesano 49, 80131 Naples, Italy
| | - Leonardo Lucantoni
- Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, 4111, Queensland, Australia
| | | | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032 Camerino, MC, Italy.
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Smith RC, Barillas-Mury C. Plasmodium Oocysts: Overlooked Targets of Mosquito Immunity. Trends Parasitol 2016; 32:979-990. [PMID: 27639778 DOI: 10.1016/j.pt.2016.08.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/26/2016] [Accepted: 08/30/2016] [Indexed: 12/18/2022]
Abstract
Although the ability of mosquitoes to limit Plasmodium infection is well documented, many questions remain as to how malaria parasites are recognized and killed by the mosquito host. Recent evidence suggests that anti-Plasmodium immunity is multimodal, with different immune mechanisms regulating ookinete and oocyst survival. However, most experiments determine the number of mature oocysts, without considering that different immune mechanisms may target different developmental stages of the parasite. Complement-like proteins have emerged as important determinants of early immunity targeting the ookinete stage, yet the mechanisms by which the mosquito late-phase immune response limits oocyst survival are less understood. Here, we describe the known components of the mosquito immune system that limit oocyst development, and provide insight into their possible mechanisms of action.
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Affiliation(s)
- Ryan C Smith
- Department of Entomology, Iowa State University, Ames, IA, USA.
| | - Carolina Barillas-Mury
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
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Bennink S, Kiesow MJ, Pradel G. The development of malaria parasites in the mosquito midgut. Cell Microbiol 2016; 18:905-18. [PMID: 27111866 PMCID: PMC5089571 DOI: 10.1111/cmi.12604] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/13/2016] [Accepted: 04/20/2016] [Indexed: 01/01/2023]
Abstract
The mosquito midgut stages of malaria parasites are crucial for establishing an infection in the insect vector and to thus ensure further spread of the pathogen. Parasite development in the midgut starts with the activation of the intraerythrocytic gametocytes immediately after take-up and ends with traversal of the midgut epithelium by the invasive ookinetes less than 24 h later. During this time period, the plasmodia undergo two processes of stage conversion, from gametocytes to gametes and from zygotes to ookinetes, both accompanied by dramatic morphological changes. Further, gamete formation requires parasite egress from the enveloping erythrocytes, rendering them vulnerable to the aggressive factors of the insect gut, like components of the human blood meal. The mosquito midgut stages of malaria parasites are unprecedented objects to study a variety of cell biological aspects, including signal perception, cell conversion, parasite/host co-adaptation and immune evasion. This review highlights recent insights into the molecules involved in gametocyte activation and gamete formation as well as in zygote-to-ookinete conversion and ookinete midgut exit; it further discusses factors that can harm the extracellular midgut stages as well as the measures of the parasites to protect themselves from any damage.
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Affiliation(s)
- Sandra Bennink
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Meike J Kiesow
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Gabriele Pradel
- Division of Cellular and Applied Infection Biology, Institute of Zoology, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
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The Nonartemisinin Sesquiterpene Lactones Parthenin and Parthenolide Block Plasmodium falciparum Sexual Stage Transmission. Antimicrob Agents Chemother 2016; 60:2108-17. [PMID: 26787692 DOI: 10.1128/aac.02002-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 01/11/2016] [Indexed: 01/17/2023] Open
Abstract
Parthenin and parthenolide are natural products that are closely related in structure to artemisinin, which is also a sesquiterpene lactone (SQL) and one of the most important antimalarial drugs available. Parthenin, like artemisinin, has an effect onPlasmodiumblood stage development. We extended the evaluation of parthenin as a potential therapeutic for the transmissible stages ofPlasmodium falciparumas it transitions between human and mosquito, with the aim of gaining potential mechanistic insight into the inhibitory activity of this compound. We posited that if parthenin targets different biological pathways in the parasite, this in turn could pave the way for the development of druggable compounds that could prevent the spread of artemisinin-resistant parasites. We examined parthenin's effect on male gamete activation and the ookinete-to-oocyst transition in the mosquito as well as on stage V gametocytes that are present in peripheral blood. Parthenin arrested parasite development for each of the stages tested. The broad inhibitory properties of parthenin on the evaluated parasite stages may suggest different mechanisms of action between parthenin and artemisinin. Parthenin's cytotoxicity notwithstanding, its demonstrated activity in this study suggests that structurally related SQLs with a better safety profile deserve further exploration. We used our battery of assays to test parthenolide, which has a more compelling safety profile. Parthenolide demonstrated activity nearly identical to that of parthenin againstP. falciparum, highlighting its potential as a possible transmission-blocking drug scaffold. We discuss the context of the evidence with respect to the next steps toward expanding the current antimalarial arsenal.
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46
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Gliding motility in apicomplexan parasites. Semin Cell Dev Biol 2015; 46:135-42. [DOI: 10.1016/j.semcdb.2015.09.020] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 09/25/2015] [Indexed: 11/22/2022]
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Wang B, Pakpour N, Napoli E, Drexler A, Glennon EKK, Surachetpong W, Cheung K, Aguirre A, Klyver JM, Lewis EE, Eigenheer R, Phinney BS, Giulivi C, Luckhart S. Anopheles stephensi p38 MAPK signaling regulates innate immunity and bioenergetics during Plasmodium falciparum infection. Parasit Vectors 2015; 8:424. [PMID: 26283222 PMCID: PMC4539710 DOI: 10.1186/s13071-015-1016-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 07/21/2015] [Indexed: 01/30/2023] Open
Abstract
Background Fruit flies and mammals protect themselves against infection by mounting immune and metabolic responses that must be balanced against the metabolic needs of the pathogens. In this context, p38 mitogen-activated protein kinase (MAPK)-dependent signaling is critical to regulating both innate immunity and metabolism during infection. Accordingly, we asked to what extent the Asian malaria mosquito Anopheles stephensi utilizes p38 MAPK signaling during infection with the human malaria parasite Plasmodium falciparum. Methods A. stephensi p38 MAPK (AsP38 MAPK) was identified and patterns of signaling in vitro and in vivo (midgut) were analyzed using phospho-specific antibodies and small molecule inhibitors. Functional effects of AsP38 MAPK inhibition were assessed using P. falciparum infection, quantitative real-time PCR, assays for reactive oxygen species and survivorship under oxidative stress, proteomics, and biochemical analyses. Results The genome of A. stephensi encodes a single p38 MAPK that is activated in the midgut in response to parasite infection. Inhibition of AsP38 MAPK signaling significantly reduced P. falciparum sporogonic development. This phenotype was associated with AsP38 MAPK regulation of mitochondrial physiology and stress responses in the midgut epithelium, a tissue critical for parasite development. Specifically, inhibition of AsP38 MAPK resulted in reduction in mosquito protein synthesis machinery, a shift in glucose metabolism, reduced mitochondrial metabolism, enhanced production of mitochondrial reactive oxygen species, induction of an array of anti-parasite effector genes, and decreased resistance to oxidative stress-mediated damage. Hence, P. falciparum-induced activation of AsP38 MAPK in the midgut facilitates parasite infection through a combination of reduced anti-parasite immune defenses and enhanced host protein synthesis and bioenergetics to minimize the impact of infection on the host and to maximize parasite survival, and ultimately, transmission. Conclusions These observations suggest that, as in mammals, innate immunity and mitochondrial responses are integrated in mosquitoes and that AsP38 MAPK-dependent signaling facilitates mosquito survival during parasite infection, a fact that may attest to the relatively longer evolutionary relationship of these parasites with their invertebrate compared to their vertebrate hosts. On a practical level, improved understanding of the balances and trade-offs between resistance and metabolism could be leveraged to generate fit, resistant mosquitoes for malaria control. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1016-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bo Wang
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Nazzy Pakpour
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Eleonora Napoli
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.
| | - Anna Drexler
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Elizabeth K K Glennon
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Win Surachetpong
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Kong Cheung
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Alejandro Aguirre
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - John M Klyver
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
| | - Edwin E Lewis
- Department of Entomology and Nematology, University of California Davis, Davis, CA, USA.
| | - Richard Eigenheer
- Genome and Biomedical Sciences Center, University of California Davis, Davis, CA, USA.
| | - Brett S Phinney
- Genome and Biomedical Sciences Center, University of California Davis, Davis, CA, USA.
| | - Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA. .,Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, CA, USA.
| | - Shirley Luckhart
- Department of Medical Microbiology and Immunology, School of Medicine, University of California Davis, 3437 Tupper Hall, One Shields Avenue, Davis, CA, 95616, USA.
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Ukegbu CV, Cho JS, Christophides GK, Vlachou D. Transcriptional silencing and activation of paternal DNA during Plasmodium berghei zygotic development and transformation to oocyst. Cell Microbiol 2015; 17:1230-40. [PMID: 25728487 PMCID: PMC4678591 DOI: 10.1111/cmi.12433] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 02/24/2015] [Accepted: 02/24/2015] [Indexed: 11/29/2022]
Abstract
The malaria parasite develops sexually in the mosquito midgut upon entry with the ingested blood meal before it can invade the midgut epithelium and embark on sporogony. Recent data have identified a number of distinct transcriptional programmes operating during this critical phase of the parasite life cycle. We aimed at characterizing the parental contribution to these transcriptional programmes and establish the genetic framework that would guide further studies of Plasmodium zygotic development and ookinete-to-oocyst transition. To achieve this we used in vitro and in vivo cross-fertilization experiments of various parasite lines expressing fluorescent reporters under the control of constitutive and stage-specific promoters. The results revealed that the zygote/ookinete stage exhibits a maternal phenotype with respect to constitutively expressed reporters, which is derived from either maternal mRNA inheritance or transcription of the maternal allele. The respective paternal alleles are silenced in the zygote/ookinete but reactivated after midgut invasion and transformation to oocyst. Transcripts specifically produced in the zygote/ookinete are synthesized de novo by both parental alleles. These findings highlight a putative role of epigenetic regulation of Plasmodium zygotic development and add substantially to the emerging picture of the molecular mechanisms regulating this important stage of malaria transmission.
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Affiliation(s)
| | - Jee-Sun Cho
- Department of Life Sciences, Imperial College London, London, UK
| | - George K Christophides
- Department of Life Sciences, Imperial College London, London, UK
- The Cyprus Institute, Nicosia, Cyprus
| | - Dina Vlachou
- Department of Life Sciences, Imperial College London, London, UK
- The Cyprus Institute, Nicosia, Cyprus
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49
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Abay SM, Lucantoni L, Dahiya N, Dori G, Dembo EG, Esposito F, Lupidi G, Ogboi S, Ouédraogo RK, Sinisi A, Taglialatela-Scafati O, Yerbanga RS, Bramucci M, Quassinti L, Ouédraogo JB, Christophides G, Habluetzel A. Plasmodium transmission blocking activities of Vernonia amygdalina extracts and isolated compounds. Malar J 2015. [PMID: 26208861 PMCID: PMC4513948 DOI: 10.1186/s12936-015-0812-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background Medicinal plants are a validated source for discovery of new leads and standardized herbal medicines. The aim of this study was to assess the activity of Vernoniaamygdalina leaf extracts and isolated compounds against gametocytes and sporogonic stages of Plasmodiumberghei and to validate the findings on field isolates of Plasmodium falciparum. Methods Aqueous (Ver-H2O) and ethanolic (Ver-EtOH) leaf extracts were tested in vivo for activity against sexual and asexual blood stage P. berghei parasites. In vivo transmission blocking effects of Ver-EtOH and Ver-H2O were estimated by assessing P. berghei oocyst prevalence and density in Anopheles stephensi mosquitoes. Activity targeting early sporogonic stages (ESS), namely gametes, zygotes and ookinetes was assessed in vitro using P. berghei CTRPp.GFP strain. Bioassay guided fractionation was performed to characterize V.amygdalina fractions and molecules for anti-ESS activity. Fractions active against ESS of the murine parasite were tested for ex vivo transmission blocking activity on P.falciparum field isolates. Cytotoxic effects of extracts and isolated compounds vernolide and vernodalol were evaluated on the human cell lines HCT116 and EA.hy926. Results Ver-H2O reduced the P. berghei macrogametocyte density in mice by about 50% and Ver-EtOH reduced P. berghei oocyst prevalence and density by 27 and 90%, respectively, in An.stephensi mosquitoes. Ver-EtOH inhibited almost completely (>90%) ESS development in vitro at 50 μg/mL. At this concentration, four fractions obtained from the ethylacetate phase of the methanol extract displayed inhibitory activity >90% against ESS. Three tested fractions were also found active against field isolates of the human parasite P. falciparum, reducing oocyst prevalence in Anopheles coluzzii mosquitoes to one-half and oocyst density to one-fourth of controls. The molecules and fractions displayed considerable cytotoxicity on the two tested cell-lines. Conclusions Vernonia amygdalina leaves contain molecules affecting multiple stages of Plasmodium, evidencing its potential for drug discovery. Chemical modification of the identified hit molecules, in particular vernodalol, could generate a library of druggable sesquiterpene lactones. The development of a multistage phytomedicine designed as preventive treatment to complement existing malaria control tools appears a challenging but feasible goal. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0812-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Solomon M Abay
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy. .,School of Medicine, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Leonardo Lucantoni
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy. .,Discovery Biology, Eskitis Institute for Drug Discovery, Griffith University, Nathan, QLD, 4111, Australia.
| | - Nisha Dahiya
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Geme Dori
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Edson G Dembo
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Fulvio Esposito
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Guilio Lupidi
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Sonny Ogboi
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Robert K Ouédraogo
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy. .,Institut de Recherche enSciences de la Santé, Direction Régionale de l'Ouest, Bobo-Dioulasso, Burkina Faso.
| | - Annamaria Sinisi
- Department of Pharmacy, University of Naples Federico II, Via Montesano 49, 80131, Naples, Italy.
| | | | - R Serge Yerbanga
- Institut de Recherche enSciences de la Santé, Direction Régionale de l'Ouest, Bobo-Dioulasso, Burkina Faso.
| | - Massimo Bramucci
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Luana Quassinti
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
| | - Jean Bosco Ouédraogo
- Institut de Recherche enSciences de la Santé, Direction Régionale de l'Ouest, Bobo-Dioulasso, Burkina Faso.
| | | | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Piazza dei Costanti, 62032, Camerino, MC, Italy.
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50
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Wirth CC, Bennink S, Scheuermayer M, Fischer R, Pradel G. Perforin-like protein PPLP4 is crucial for mosquito midgut infection by Plasmodium falciparum. Mol Biochem Parasitol 2015; 201:90-9. [PMID: 26166358 DOI: 10.1016/j.molbiopara.2015.06.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 02/05/2023]
Abstract
The genomes of Plasmodium parasites encode for five perforin-like proteins, PPLP1-5, and four of them have previously been demonstrated to be involved in disruption of host cell barriers. We now show that the fifth perforin, PPLP4, is crucial for infection of the mosquito vector by Plasmodium falciparum parasites. PPLP4 is expressed in the blood and mosquito midgut stages in granular structures. In gametocytes, PPLP4 expression is specific to the female gender, while ookinetes show a PPLP4 localization at the apical pole. Gene disruption of pplp4 results in no phenotypical change during blood stage replication, gametocyte development or gametogenesis, while mosquitoes fed with PPLP4-deficient gametocytes display a severe reduction in oocyst numbers, and an accumulation of ookinetes in the mosquito midguts was observed. In conclusion, we propose an essential role for PPLP4 in infection of the mosquito midgut, presumably by mediating ookinete traversal through the midgut epithelium.
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Affiliation(s)
- Christine C Wirth
- Cellular and Applied Infection Biology Section, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Sandra Bennink
- Cellular and Applied Infection Biology Section, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Matthias Scheuermayer
- Research Center for Infectious Diseases, University of Würzburg, Josef-Schneider-Str. 2/D15, 97080 Würzburg, Germany
| | - Rainer Fischer
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Forckenbeckstr. 6, 52074 Aachen, Germany
| | - Gabriele Pradel
- Cellular and Applied Infection Biology Section, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology, Forckenbeckstr. 6, 52074 Aachen, Germany.
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