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Alencar RM, Sepulveda CCP, Martinez-Villegas L, Bahia AC, Santana RA, de Souza IB, D'Elia GMA, Duarte APM, de Lacerda MVG, Monteiro WM, Secundino NFC, Pimenta PFP, Koerich LB. Unravelling the genome of the brackish water malaria vector Anopheles aquasalis. Sci Rep 2023; 13:20472. [PMID: 37993652 PMCID: PMC10665375 DOI: 10.1038/s41598-023-47830-1] [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: 02/09/2023] [Accepted: 11/19/2023] [Indexed: 11/24/2023] Open
Abstract
Malaria is a severe public health problem in several developing tropical and subtropical countries. Anopheles aquasalis is the primary coastal malaria vector in Central and South America and the Caribbean Islands, and it has the peculiar feature of living in water with large changes in salinity. Recent research has recognised An. aquasalis as an important model for studying the interactions of murine and human Plasmodium parasites. This study presents the complete genome of An. aquasalis and offers insights into its evolution and physiology. The genome is similar in size and gene content to other Neotropical anophelines, with 162 Mb and 12,446 protein-coding genes. There are 1387 single-copy orthologs at the Diptera level (eg. An. gambiae, An. darlingi and Drosophila melanogaster). An. aquasalis diverged from An. darlingi, the primary malaria vector in inland South America, nearly 20 million years ago. Proteins related to ion transport and metabolism belong to the most abundant gene families with 660 genes. We identified gene families relevant to osmosis control (e.g., aquaporins, vacuolar-ATPases, Na+/K+-ATPases, and carbonic anhydrases). Evolutionary analysis suggests that all osmotic regulation genes are under strong purifying selection. We also observed low copy number variation in insecticide resistance and immunity-related genes for all known classical pathways. The data provided by this study offers candidate genes for further studies of parasite-vector interactions and for studies on how anophelines of brackish water deal with the high fluctuation in water salinity. We also established data and insights supporting An. aquasalis as an emerging Neotropical malaria vector model for genetic and molecular studies.
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Affiliation(s)
- Rodrigo Maciel Alencar
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Cesar Camilo Prado Sepulveda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Luis Martinez-Villegas
- Instituto de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil
- Programa de Pós-Graduação em Ciências da Saúde, FIOCRUZ, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil
| | - Ana Cristina Bahia
- Laboratório de Bioquímica de Insetos e Parasitos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, CEP 21.941-170, Brazil
| | - Rosa Amélia Santana
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
- Instituto de Pesquisa Leônidas & Maria Deane, Fundação Oswaldo Cruz, Manaus, Amazonas, CEP 69.027-070, Brazil
| | - Igor Belém de Souza
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Gigliola Mayara Ayres D'Elia
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Ana Paula Marques Duarte
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Marcus Vinicius Guimarães de Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Instituto de Pesquisa Leônidas & Maria Deane, Fundação Oswaldo Cruz, Manaus, Amazonas, CEP 69.027-070, Brazil
- University of Texas Medical Branch, Galveston, United States of America
| | - Wuelton Marcelo Monteiro
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
| | - Nágila Francinete Costa Secundino
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil
- Instituto de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil
- Programa de Pós-Graduação em Ciências da Saúde, FIOCRUZ, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil
| | - Paulo Filemon Paolucci Pimenta
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, CEP 69.040-000, Brazil.
- Programa de Pós-Graduação em Medicina Tropical, Fundação de Medicina Tropical Heitor Vieira Dourado, Universidade do Estado do Amazonas, Manaus, Amazonas, CEP 69.040-000, Brazil.
- Instituto de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil.
- Programa de Pós-Graduação em Ciências da Saúde, FIOCRUZ, Belo Horizonte, Minas Gerais, CEP 30.190-009, Brazil.
| | - Leonardo Barbosa Koerich
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, CEP 31.270-901, Brazil.
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van de Vegte-Bolmer M, Graumans W, Stoter R, van Gemert GJ, Sauerwein R, Collins KA, Bousema T. A portfolio of geographically distinct laboratory-adapted Plasmodium falciparum clones with consistent infection rates in Anopheles mosquitoes. Malar J 2021; 20:381. [PMID: 34565372 PMCID: PMC8474906 DOI: 10.1186/s12936-021-03912-x] [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: 05/27/2021] [Accepted: 09/09/2021] [Indexed: 12/18/2022] Open
Abstract
Background The ability to culture Plasmodium falciparum continuously in vitro has enabled stable access to asexual and sexual parasites for malaria research. The portfolio of isolates has remained limited and research is still largely based on NF54 and its derived clone 3D7. Since 1978, isolates were collected and cryopreserved at Radboudumc from patients presenting at the hospital. Here, procedures are described for culture adaptation of asexual parasites, cloning and production of sexual stage parasites responsible for transmission (gametocytes) and production of oocysts in Anopheles mosquitoes. This study aimed to identify new culture-adapted transmissible P. falciparum isolates, originating from distinct geographical locations. Methods Out of a collection of 121 P. falciparum isolates stored in liquid nitrogen, 21 from different geographical origin were selected for initial testing. Isolates were evaluated for their ability to be asexually cultured in vitro, their gametocyte production capacity, and consistent generation of oocysts. Results Out of 21 isolates tested, twelve were excluded from further analysis due to lack of mature gametocyte production (n = 1) or generation of satisfactory numbers of oocysts in mosquitoes (n = 11). Nine isolates fulfilled selection criteria and were cloned by limiting dilution and retested. After cloning, one isolate was excluded for not showing transmission. The remaining eight isolates transmitted to Anopheles stephensi or Anopheles coluzzii mosquitoes and were categorized into two groups with a reproducible mean oocyst infection intensity above (n = 5) or below five (n = 3). Conclusions These new P. falciparum culture-adapted isolates with reproducible transmission to Anopheles mosquitoes are a valuable addition to the malaria research tool box. They can aid in the development of malaria interventions and will be particularly useful for those studying malaria transmission. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03912-x.
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Affiliation(s)
- Marga van de Vegte-Bolmer
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Wouter Graumans
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rianne Stoter
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Geert-Jan van Gemert
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | | | - Katharine A Collins
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Teun Bousema
- Radboud Institute for Health Sciences and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, The Netherlands. .,Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK.
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Coelho CH, Nadakal ST, Gonzales Hurtado P, Morrison R, Galson JD, Neal J, Wu Y, King CR, Price V, Miura K, Wong-Madden S, Alamou Doritchamou JY, Narum DL, MacDonald NJ, Snow-Smith M, Vignali M, Taylor JJ, Lefranc MP, Trück J, Long CA, Sagara I, Fried M, Duffy PE. Antimalarial antibody repertoire defined by plasma IG proteomics and single B cell IG sequencing. JCI Insight 2020; 5:143471. [PMID: 33048842 PMCID: PMC7710313 DOI: 10.1172/jci.insight.143471] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 10/07/2020] [Indexed: 01/15/2023] Open
Abstract
Plasma antimalarial Ab can mediate antiparasite immunity but has not previously been characterized at the molecular level. Here, we develop an innovative strategy to characterize humoral responses by integrating profiles of plasma immunoglobulins (IGs) or Abs with those expressed on B cells as part of the B cell receptor. We applied this strategy to define plasma IG and to determine variable (V) gene usage after vaccination with the Plasmodium falciparum zygote antigen Pfs25. Using proteomic tools coupled with bulk immunosequencing data, we determined human antigen-binding fragment [F(ab')2] peptide sequences from plasma IG of adults who received 4 doses of Pfs25-EPA/Alhydrogel. Specifically, Pfs25 antigen-specific F(ab')2 peptides (Pfs25-IG) were aligned to cDNA sequences of IG heavy (IGH) chain complementarity determining region 3 from a data set generated by total peripheral B cell immunosequencing of the entire vaccinated population. IGHV4 was the most commonly identified IGHV subgroup of Pfs25-IG, a pattern that was corroborated by V heavy/V light chain sequencing of Pfs25-specific single B cells from 5 vaccinees and by matching plasma Pfs25-IG peptides and V-(D)-J sequences of Pfs25-specific single B cells from the same donor. Among 13 recombinant human mAbs generated from IG sequences of Pfs25-specific single B cells, a single IGHV4 mAb displayed strong neutralizing activity, reducing the number of P. falciparum oocysts in infected mosquitoes by more than 80% at 100 μg/mL. Our approach characterizes the human plasma Ab repertoire in response to the Pfs25-EPA/Alhydrogel vaccine and will be useful for studying circulating Abs in response to other vaccines as well as those induced during infections or autoimmune disorders.
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MESH Headings
- Adjuvants, Immunologic
- Adolescent
- Adult
- Antibodies, Monoclonal/blood
- Antibodies, Monoclonal/immunology
- Antibodies, Protozoan/blood
- Antibodies, Protozoan/immunology
- Antigens, Protozoan/immunology
- Antimalarials/administration & dosage
- Antimalarials/immunology
- B-Lymphocytes/immunology
- Clinical Trials as Topic
- Female
- Humans
- Immunoglobulins/blood
- Immunoglobulins/immunology
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/immunology
- Malaria, Falciparum/blood
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Male
- Middle Aged
- Plasmodium falciparum/immunology
- Protozoan Proteins/immunology
- Vaccination
- Young Adult
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Affiliation(s)
- Camila H. Coelho
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Steven T. Nadakal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Patricia Gonzales Hurtado
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Robert Morrison
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Jacob D. Galson
- University Children’s Hospital Zurich, Zurich, Switzerland
- Alchemab Therapeutics Ltd, London, United Kingdom
| | - Jillian Neal
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Yimin Wu
- PATH’s Malaria Vaccine Initiative, Washington, DC, USA
| | | | | | - Kazutoyo Miura
- Laboratory of Malaria and Vector and Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, USA
| | - Sharon Wong-Madden
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Justin Yai Alamou Doritchamou
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - David L. Narum
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Nicholas J. MacDonald
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Maryonne Snow-Smith
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Marissa Vignali
- Laboratory of Malaria and Vector and Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, USA
- Adaptive Biotechnologies Corp, Seattle, Washington, USA
| | - Justin J. Taylor
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Marie-Paule Lefranc
- IMGT, the International ImMunoGeneTics Information System, Laboratoire d’ImmunoGénétique Moléculaire, Institut de Génétique Humaine, UMR9002 CNRS, Université de Montpellier, Montpellier, France
| | - Johannes Trück
- University Children’s Hospital Zurich, Zurich, Switzerland
| | - Carole A. Long
- Laboratory of Malaria and Vector and Research, National Institute of Allergy and Infectious Diseases, NIH, Rockville, Maryland, USA
| | - Issaka Sagara
- Malaria Research and Training Center, University of Sciences, Techniques, and Technologies, Bamako, Mali
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Patrick E. Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
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High Plasmodium infection intensity in naturally infected malaria vectors in Africa. Int J Parasitol 2020; 50:985-996. [PMID: 32681932 DOI: 10.1016/j.ijpara.2020.05.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 05/14/2020] [Accepted: 05/17/2020] [Indexed: 01/18/2023]
Abstract
The population dynamics of human to mosquito malaria transmission in the field has important implications for the genetics, epidemiology and control of malaria. The number of oocysts in oocyst-positive mosquitoes developing from a single, naturally acquired infectious blood meal (herein referred to as a single-feed infection load) greatly influences the efficacy of transmission blocking interventions but still remains poorly documented. During a year-long analysis of malaria parasite transmission in Burkina Faso we caught and dissected wild malaria vectors to assess Plasmodium oocyst prevalence and load (the number of oocysts counted in mosquitoes with detectable oocysts) and the prevalence of salivary gland sporozoites. This was compared with malaria endemicity in the human population, assessed in cross-sectional surveys. Data were analysed using a novel transmission mathematical model to estimate the per bite transmission probability and the average single-feed infection load for each location. The observed oocyst load and the estimated single-feed infection load in naturally infected mosquitoes were substantially higher than previous estimates (means ranging from 3.2 to 24.5 according to seasons and locations) and indicate a strong positive association between the single-feed infection load and parasite prevalence in humans. This work suggests that highly infected mosquitoes are not rare in the field and might have a greater influence on the epidemiology and genetics of the parasite, and on the efficacy of novel transmission blocking interventions.
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de Jong RM, Tebeje SK, Meerstein‐Kessel L, Tadesse FG, Jore MM, Stone W, Bousema T. Immunity against sexual stage Plasmodium falciparum and Plasmodium vivax parasites. Immunol Rev 2020; 293:190-215. [PMID: 31840844 PMCID: PMC6973022 DOI: 10.1111/imr.12828] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/30/2019] [Accepted: 11/14/2019] [Indexed: 12/25/2022]
Abstract
The efficient spread of malaria from infected humans to mosquitoes is a major challenge for malaria elimination initiatives. Gametocytes are the only Plasmodium life stage infectious to mosquitoes. Here, we summarize evidence for naturally acquired anti-gametocyte immunity and the current state of transmission blocking vaccines (TBV). Although gametocytes are intra-erythrocytic when present in infected humans, developing Plasmodium falciparum gametocytes may express proteins on the surface of red blood cells that elicit immune responses in naturally exposed individuals. This immune response may reduce the burden of circulating gametocytes. For both P. falciparum and Plasmodium vivax, there is a solid evidence that antibodies against antigens present on the gametocyte surface, when co-ingested with gametocytes, can influence transmission to mosquitoes. Transmission reducing immunity, reducing the burden of infection in mosquitoes, is a well-acknowledged but poorly quantified phenomenon that forms the basis for the development of TBV. Transmission enhancing immunity, increasing the likelihood or intensity of transmission to mosquitoes, is more speculative in nature but is convincingly demonstrated for P. vivax. With the increased interest in malaria elimination, TBV and monoclonal antibodies have moved to the center stage of malaria vaccine development. Methodologies to prioritize and evaluate products are urgently needed.
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MESH Headings
- Antibodies, Blocking/immunology
- Antibodies, Protozoan/immunology
- Host-Parasite Interactions/immunology
- Humans
- Immunity
- Immunomodulation
- Life Cycle Stages
- Malaria Vaccines/immunology
- Malaria, Falciparum/immunology
- Malaria, Falciparum/parasitology
- Malaria, Falciparum/prevention & control
- Malaria, Falciparum/transmission
- Malaria, Vivax/immunology
- Malaria, Vivax/parasitology
- Malaria, Vivax/prevention & control
- Malaria, Vivax/transmission
- Plasmodium falciparum/growth & development
- Plasmodium falciparum/immunology
- Plasmodium vivax/growth & development
- Plasmodium vivax/immunology
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Affiliation(s)
- Roos M. de Jong
- Radboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | | | - Lisette Meerstein‐Kessel
- Radboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
- Centre for Molecular and Biomolecular InformaticsRadboud Institute for Molecular Life SciencesNijmegenThe Netherlands
| | - Fitsum G. Tadesse
- Armauer Hansen Research InstituteAddis AbabaEthiopia
- Radboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - Matthijs M. Jore
- Radboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenThe Netherlands
| | - Will Stone
- Department of Immunology and InfectionLondon School of Hygiene and Tropical MedicineLondonUK
| | - Teun Bousema
- Radboud Institute for Health SciencesRadboud University Medical CenterNijmegenThe Netherlands
- Department of Immunology and InfectionLondon School of Hygiene and Tropical MedicineLondonUK
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6
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Pathak AK, Shiau JC, Thomas MB, Murdock CC. Field Relevant Variation in Ambient Temperature Modifies Density-Dependent Establishment of Plasmodium falciparum Gametocytes in Mosquitoes. Front Microbiol 2019; 10:2651. [PMID: 31803169 PMCID: PMC6873802 DOI: 10.3389/fmicb.2019.02651] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Accepted: 10/30/2019] [Indexed: 12/29/2022] Open
Abstract
The relationship between Plasmodium falciparum gametocyte density and infections in mosquitoes is central to understanding the rates of transmission with important implications for control. Here, we determined whether field relevant variation in environmental temperature could also modulate this relationship. Anopheles stephensi were challenged with three densities of P. falciparum gametocytes spanning a ~10-fold gradient, and housed under diurnal/daily temperature range ("DTR") of 9°C (+5°C and -4°C) around means of 20, 24, and 28°C. Vector competence was quantified as the proportion of mosquitoes infected with oocysts in the midguts (oocyst rates) or infectious with sporozoites in the salivary glands (sporozoite rates) at peak periods of infection for each temperature to account for the differences in development rates. In addition, oocyst intensities were also recorded from infected midguts and the overall study replicated across three separate parasite cultures and mosquito cohorts. While vector competence was similar at 20 DTR 9°C and 24 DTR 9°C, oocyst and sporozoite rates were also comparable, with evidence, surprisingly, for higher vector competence in mosquitoes challenged with intermediate gametocyte densities. For the same gametocyte densities however, severe reductions in the sporozoite rates was accompanied by a significant decline in overall vector competence at 28 DTR 9°C, with gametocyte density per se showing a positive and linear effect at this temperature. Unlike vector competence, oocyst intensities decreased with increasing temperatures with a predominantly positive and linear association with gametocyte density, especially at 28 DTR 9°C. Oocyst intensities across individual infected midguts suggested temperature-specific differences in mosquito susceptibility/resistance: at 20 DTR 9°C and 24 DTR 9°C, dispersion (aggregation) increased in a density-dependent manner but not at 28 DTR 9°C where the distributions were consistently random. Limitations notwithstanding, our results suggest that variation in temperature could modify seasonal dynamics of infectious reservoirs with implications for the design and deployment of transmission-blocking vaccines/drugs.
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Affiliation(s)
- Ashutosh K. Pathak
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Ecology of Infectious Diseases, University of Georgia, Athens, GA, United States
- Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Justine C. Shiau
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
| | - Matthew B. Thomas
- The Department of Entomology, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, United States
| | - Courtney C. Murdock
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States
- Center for Ecology of Infectious Diseases, University of Georgia, Athens, GA, United States
- Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, United States
- Odum School of Ecology, University of Georgia, Athens, GA, United States
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, United States
- Riverbasin Center, University of Georgia, Athens, GA, United States
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7
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Julien JP, Wardemann H. Antibodies against Plasmodium falciparum malaria at the molecular level. Nat Rev Immunol 2019; 19:761-775. [DOI: 10.1038/s41577-019-0209-5] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2019] [Indexed: 12/11/2022]
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8
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Kooistra RL, David R, Ruiz AC, Powers SW, Haselton KJ, Kiernan K, Blagborough AM, Solamen L, Olsen KW, Putonti C, Kanzok SM. Characterization of a protozoan Phosducin-like protein-3 (PhLP-3) reveals conserved redox activity. PLoS One 2019; 13:e0209699. [PMID: 30596727 PMCID: PMC6312279 DOI: 10.1371/journal.pone.0209699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/09/2018] [Indexed: 11/18/2022] Open
Abstract
We recently identified three novel thioredoxin-like genes in the genome of the protozoan parasite Plasmodium that belong to the Phosducin-like family of proteins (PhLP). PhLPs are small cytosolic proteins hypothesized to function in G-protein signaling and protein folding. Although PhLPs are highly conserved in eukaryotes from yeast to mammals, only a few representatives have been experimentally characterized to date. In addition, while PhLPs contain a thioredoxin domain, they lack a CXXC motif, a strong indicator for redox activity, and it is unclear whether members of the PhLP family are enzymatically active. Here, we describe PbPhLP-3 as the first phosducin-like protein of a protozoan organism, Plasmodium berghei. Initial transcription analysis revealed continuous low-level expression of pbphlp-3 throughout the complex Plasmodium life cycle. Attempts to knockout pbphlp-3 in P. berghei did not yield live parasites, suggesting an essential role for the gene in Plasmodium. We cloned, expressed and purified PbPhLP-3 and determined that the recombinant protein is redox active in vitro in a thioredoxin-coupled redox assay. It also has the capacity to reduce the organic compound tert-Butyl hydroperoxide (TBHP) in vitro, albeit at low efficiency. Sequence analysis, structural modeling, and site-directed mutagenesis revealed a conserved cysteine in the thioredoxin domain to be the redox active residue. Lastly, we provide evidence that recombinant human PhLP-3 exhibits redox activity similar to that of PbPhLP-3 and suggest that redox activity may be conserved in PhLP-3 homologs of other species. Our data provide new insight into the function of PhLP-3, which is hypothesized to act as co-chaperones in the folding and regulation of cytoskeletal proteins. We discuss the potential implications of PhLP-3 as a thioredoxin-target protein and possible links between the cellular redox network and the eukaryotic protein folding machinery.
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Affiliation(s)
- Rachel L. Kooistra
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Robin David
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Ana C. Ruiz
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Sean W. Powers
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Kyle J. Haselton
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Kaitlyn Kiernan
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
| | - Andrew M. Blagborough
- Department of Life Sciences, Imperial College London, South Kensington Campus, London, United Kingdom
| | - Ligin Solamen
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
- Bioinformatics Program, Loyola University Chicago, Chicago, IL, United States of America
| | - Kenneth W. Olsen
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL, United States of America
| | - Catherine Putonti
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
- Bioinformatics Program, Loyola University Chicago, Chicago, IL, United States of America
- Department of Computer Science, Loyola University Chicago, Chicago, IL, United States of America
| | - Stefan M. Kanzok
- Department of Biology, Loyola University Chicago, Chicago, IL, United States of America
- Bioinformatics Program, Loyola University Chicago, Chicago, IL, United States of America
- * E-mail:
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9
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Pathak AK, Shiau JC, Thomas MB, Murdock CC. Cryogenically preserved RBCs support gametocytogenesis of Plasmodium falciparum in vitro and gametogenesis in mosquitoes. Malar J 2018; 17:457. [PMID: 30522507 PMCID: PMC6282341 DOI: 10.1186/s12936-018-2612-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 12/01/2018] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND The malaria Eradication Research Agenda (malERA) has identified human-to-mosquito transmission of Plasmodium falciparum as a major target for eradication. The cornerstone for identifying and evaluating transmission in the laboratory is standard membrane feeding assays (SMFAs) where mature gametocytes of P. falciparum generated in vitro are offered to mosquitoes as part of a blood-meal. However, propagation of "infectious" gametocytes requires 10-12 days with considerable physico-chemical demands imposed on host RBCs and thus, "fresh" RBCs that are ≤ 1-week old post-collection are generally recommended. However, in addition to the costs, physico-chemical characteristics unique to RBC donors may confound reproducibility and interpretation of SMFAs. Cryogenic storage of RBCs ("cryo-preserved RBCs") is accepted by European and US FDAs as an alternative to refrigeration (4 °C) for preserving RBC "quality" and while cryo-preserved RBCs have been used for in vitro cultures of other Plasmodia and the asexual stages of P. falciparum, none of the studies required RBCs to support parasite development for > 4 days. RESULTS Using the standard laboratory strain, P. falciparum NF54, 11 SMFAs were performed with RBCs from four separate donors to demonstrate that RBCs cryo-preserved in the gaseous phase of liquid nitrogen (- 196 °C) supported gametocytogenesis in vitro and subsequent gametogenesis in Anopheles stephensi mosquitoes. Overall levels of sporogony in the mosquito, as measured by oocyst and sporozoite prevalence, as well as oocyst burden, from each of the four donors thawed after varying intervals of cryopreservation (1, 4, 8, and 12 weeks) were comparable to using ≤ 1-week old refrigerated RBCs. Lastly, the potential for cryo-preserved RBCs to serve as a suitable alternative substrate is demonstrated for a Cambodian isolate of P. falciparum across two independent SMFAs. CONCLUSIONS Basic guidelines are presented for integrating cryo-preserved RBCs into an existing laboratory/insectary framework for P. falciparum SMFAs with significant potential for reducing running costs while achieving greater reliability. Lastly, scenarios are discussed where cryo-preserved RBCs may be especially useful in enhancing the understanding and/or providing novel insights into the patterns and processes underlying human-to-mosquito transmission.
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Affiliation(s)
- Ashutosh K Pathak
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, 30602, USA.
| | - Justine C Shiau
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, 30602, USA
| | - Matthew B Thomas
- Center for Infectious Disease Dynamics and the Department of Entomology, Pennsylvania State University, State College, PA, 16803, USA
| | - Courtney C Murdock
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, 30602, USA
- Odum School of Ecology, University of Georgia, Athens, GA, 30602, USA
- Center for Ecology of Infectious Diseases, University of Georgia, Athens, GA, 30602, USA
- Center for Tropical Emerging Global Diseases, University of Georgia, Athens, GA, 30602, USA
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, 30602, USA
- Riverbasin Center, University of Georgia, Athens, GA, 30602, USA
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10
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Plasmodium genomics: an approach for learning about and ending human malaria. Parasitol Res 2018; 118:1-27. [PMID: 30402656 DOI: 10.1007/s00436-018-6127-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/19/2018] [Indexed: 12/31/2022]
Abstract
Malaria causes high levels of morbidity and mortality in human beings worldwide. According to the World Health Organization (WHO), about half a million people die of this disease each year. Malaria is caused by six species of parasites belonging to the Plasmodium genus: P. falciparum, P. knowlesi, P. vivax, P. malariae, P. ovale curtisi, and P. ovale wallikeri. Currently, malaria is being kept under control with varying levels of elimination success in different countries. The development of new molecular tools as well as the use of next-generation sequencing (NGS) technologies and novel bioinformatic approaches has improved our knowledge of malarial epidemiology, diagnosis, treatment, vaccine development, and surveillance strategies. In this work, the genetics and genomics of human malarias have been analyzed. Since the first P. falciparum genome was sequenced in 2002, various population-level genetic and genomic surveys, together with transcriptomic and proteomic studies, have shown the importance of molecular approaches in supporting malaria elimination.
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