1
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441 DOI: 10.12688/wellcomeopenres.16168.1] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
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Ahouidi A, Ali M, Almagro-Garcia J, Amambua-Ngwa A, Amaratunga C, Amato R, Amenga-Etego L, Andagalu B, Anderson TJC, Andrianaranjaka V, Apinjoh T, Ariani C, Ashley EA, Auburn S, Awandare GA, Ba H, Baraka V, Barry AE, Bejon P, Bertin GI, Boni MF, Borrmann S, Bousema T, Branch O, Bull PC, Busby GBJ, Chookajorn T, Chotivanich K, Claessens A, Conway D, Craig A, D'Alessandro U, Dama S, Day NPJ, Denis B, Diakite M, Djimdé A, Dolecek C, Dondorp AM, Drakeley C, Drury E, Duffy P, Echeverry DF, Egwang TG, Erko B, Fairhurst RM, Faiz A, Fanello CA, Fukuda MM, Gamboa D, Ghansah A, Golassa L, Goncalves S, Hamilton WL, Harrison GLA, Hart L, Henrichs C, Hien TT, Hill CA, Hodgson A, Hubbart C, Imwong M, Ishengoma DS, Jackson SA, Jacob CG, Jeffery B, Jeffreys AE, Johnson KJ, Jyothi D, Kamaliddin C, Kamau E, Kekre M, Kluczynski K, Kochakarn T, Konaté A, Kwiatkowski DP, Kyaw MP, Lim P, Lon C, Loua KM, Maïga-Ascofaré O, Malangone C, Manske M, Marfurt J, Marsh K, Mayxay M, Miles A, Miotto O, Mobegi V, Mokuolu OA, Montgomery J, Mueller I, Newton PN, Nguyen T, Nguyen TN, Noedl H, Nosten F, Noviyanti R, Nzila A, Ochola-Oyier LI, Ocholla H, Oduro A, Omedo I, Onyamboko MA, Ouedraogo JB, Oyebola K, Pearson RD, Peshu N, Phyo AP, Plowe CV, Price RN, Pukrittayakamee S, Randrianarivelojosia M, Rayner JC, Ringwald P, Rockett KA, Rowlands K, Ruiz L, Saunders D, Shayo A, Siba P, Simpson VJ, Stalker J, Su XZ, Sutherland C, Takala-Harrison S, Tavul L, Thathy V, Tshefu A, Verra F, Vinetz J, Wellems TE, Wendler J, White NJ, Wright I, Yavo W, Ye H. An open dataset of Plasmodium falciparum genome variation in 7,000 worldwide samples. Wellcome Open Res 2021; 6:42. [PMID: 33824913 PMCID: PMC8008441.2 DOI: 10.12688/wellcomeopenres.16168.2] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2021] [Indexed: 02/02/2023] Open
Abstract
MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.
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Affiliation(s)
| | | | - Mozam Ali
- Wellcome Sanger Institute, Hinxton, UK
| | - Jacob Almagro-Garcia
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Alfred Amambua-Ngwa
- Wellcome Sanger Institute, Hinxton, UK,Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Chanaki Amaratunga
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Roberto Amato
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Lucas Amenga-Etego
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana,West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana
| | - Ben Andagalu
- United States Army Medical Research Directorate-Africa, Kenya Medical Research Institute/Walter Reed Project, Kisumu, Kenya
| | | | | | | | | | - Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Sarah Auburn
- Menzies School of Health Research, Darwin, Australia,Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Gordon A. Awandare
- West African Centre for Cell Biology of Infectious Pathogens (WACCBIP), University of Ghana, Accra, Ghana,University of Ghana, Legon, Ghana
| | - Hampate Ba
- Institut National de Recherche en Santé Publique, Nouakchott, Mauritania
| | - Vito Baraka
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,Department of Epidemiology, International Health Unit, University of Antwerp, Antwerp, Belgium
| | - Alyssa E. Barry
- Deakin University, Geelong, Australia,Burnet Institute, Melbourne, Australia,Walter and Eliza Hall Institute, Melbourne, Australia
| | - Philip Bejon
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Maciej F. Boni
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Steffen Borrmann
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Teun Bousema
- London School of Hygiene and Tropical Medicine, London, UK,Radboud University Medical Center, Nijmegen, The Netherlands
| | - Oralee Branch
- NYU School of Medicine Langone Medical Center, New York, USA
| | - Peter C. Bull
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Pathology, University of Cambridge, Cambridge, UK
| | - George B. J. Busby
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Antoine Claessens
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia,LPHI, MIVEGEC, INSERM, CNRS, IRD, University of Montpellier, Montpellier, France
| | - David Conway
- London School of Hygiene and Tropical Medicine, London, UK
| | - Alister Craig
- Liverpool School of Tropical Medicine, Liverpool, UK,Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Umberto D'Alessandro
- Medical Research Council Unit The Gambia, at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Souleymane Dama
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Nicholas PJ Day
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Brigitte Denis
- Malawi-Liverpool-Wellcome Trust Clinical Research, Blantyre, Malawi
| | - Mahamadou Diakite
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Djimdé
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali
| | | | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Chris Drakeley
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Patrick Duffy
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Diego F. Echeverry
- Centro Internacional de Entrenamiento e Investigaciones Médicas - CIDEIM, Cali, Colombia,Universidad Icesi, Cali, Colombia
| | | | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | | | | | - Mark M. Fukuda
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Anita Ghansah
- Nogouchi Memorial Institute for Medical Research, Legon-Accra, Ghana
| | - Lemu Golassa
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - William L. Hamilton
- Wellcome Sanger Institute, Hinxton, UK,Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | | | - Lee Hart
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Christa Henrichs
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | | | - Christina Hubbart
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Deus S. Ishengoma
- National Institute for Medical Research (NIMR), Dar es Salaam, Tanzania,East African Consortium for Clinical Research (EACCR), Dar es Salaam, Tanzania
| | - Scott A. Jackson
- Center for Applied Genetic Technologies, University of Georgia, Athens, GA, USA
| | | | - Ben Jeffery
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Anna E. Jeffreys
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Kimberly J. Johnson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | | | - Edwin Kamau
- Walter Reed Army Institute of Research, U.S. Military HIV Research Program, Silver Spring, MD, USA
| | | | - Krzysztof Kluczynski
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Theerarat Kochakarn
- Wellcome Sanger Institute, Hinxton, UK,Mahidol University, Bangkok, Thailand
| | | | - Dominic P. Kwiatkowski
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Myat Phone Kyaw
- The Myanmar Oxford Clinical Research Unit, University of Oxford, Yangon, Myanmar,University of Public Health, Yangon, Myanmar
| | - Pharath Lim
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA,Medical Care Development International, Maryland, USA
| | - Chanthap Lon
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | | | - Oumou Maïga-Ascofaré
- Malaria Research and Training Centre, University of Science, Techniques and Technologies of Bamako, Bamako, Mali,Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Research in Tropical Medicine, Kwame Nkrumah University of Sciences and Technology, Kumasi, Ghana
| | | | | | - Jutta Marfurt
- Menzies School of Health Research, Darwin, Australia
| | - Kevin Marsh
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,African Academy of Sciences, Nairobi, Kenya
| | - Mayfong Mayxay
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Vientiane, Lao People's Democratic Republic,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao People's Democratic Republic
| | - Alistair Miles
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Olivo Miotto
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK,Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Victor Mobegi
- School of Medicine, University of Nairobi, Nairobi, Kenya
| | - Olugbenga A. Mokuolu
- Department of Paediatrics and Child Health, University of Ilorin, Ilorin, Nigeria
| | - Jacqui Montgomery
- Institute of Vector-Borne Disease, Monash University, Clayton, Victoria, 3800, Australia
| | - Ivo Mueller
- Walter and Eliza Hall Institute, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Paul N. Newton
- Wellcome Trust-Mahosot Hospital-Oxford Tropical Medicine Research Collaboration, Vientiane, Lao People's Democratic Republic
| | | | - Thuy-Nhien Nguyen
- Oxford University Clinical Research Unit (OUCRU), Ho Chi Minh City, Vietnam
| | - Harald Noedl
- MARIB - Malaria Research Initiative Bandarban, Bandarban, Bangladesh
| | - Francois Nosten
- Nuffield Department of Medicine, University of Oxford, Oxford, UK,Shoklo Malaria Research Unit, Bangkok, Thailand
| | | | - Alexis Nzila
- King Fahid University of Petroleum and Minerals (KFUMP), Dharhran, Saudi Arabia
| | | | - Harold Ocholla
- KEMRI - Centres for Disease Control and Prevention (CDC) Research Program, Kisumu, Kenya,Centre for Bioinformatics and Biotechnology, University of Nairobi, Nairobi, Kenya
| | - Abraham Oduro
- Navrongo Health Research Centre, Ghana Health Service, Navrongo, Ghana
| | - Irene Omedo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Marie A. Onyamboko
- Kinshasa School of Public Health, University of Kinshasa, Kinshasa, Congo, Democratic Republic
| | | | - Kolapo Oyebola
- Nigerian Institute of Medical Research, Lagos, Nigeria,Parasitology and Bioinformatics Unit, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Richard D. Pearson
- Wellcome Sanger Institute, Hinxton, UK,MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - Norbert Peshu
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | - Aung Pyae Phyo
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Shoklo Malaria Research Unit, Bangkok, Thailand
| | - Chris V. Plowe
- School of Medicine, University of Maryland, Baltimore, MD, USA
| | - Ric N. Price
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand,Menzies School of Health Research, Darwin, Australia,Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Milijaona Randrianarivelojosia
- Institut Pasteur de Madagascar, Antananarivo, Madagascar,Universités d'Antananarivo et de Mahajanga, Antananarivo, Madagascar
| | | | | | - Kirk A. Rockett
- Wellcome Sanger Institute, Hinxton, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | | | - Lastenia Ruiz
- Universidad Nacional de la Amazonia Peruana, Iquitos, Peru
| | - David Saunders
- Department of Immunology and Medicine, US Army Medical Component, Armed Forces Research Institute of Medical Sciences (USAMC-AFRIMS), Bangkok, Thailand
| | - Alex Shayo
- Nelson Mandela Institute of Science and Technology, Arusha, Tanzania
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Victoria J. Simpson
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | | | - Xin-zhuan Su
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | | | - Shannon Takala-Harrison
- Center for Vaccine Development and Global Health, University of Maryland, School of Medicine, Baltimore, MD, USA
| | - Livingstone Tavul
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Vandana Thathy
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya,Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York, USA
| | | | | | - Joseph Vinetz
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacion y Desarrollo, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru,Yale School of Medicine, New Haven, CT, USA
| | - Thomas E. Wellems
- National Institute of Allergy and Infectious Diseases (NIAID), NIH, Bethesda, USA
| | - Jason Wendler
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Bangkok, Thailand
| | - Ian Wright
- MRC Centre for Genomics and Global Health, Big Data Institute, University of Oxford, Oxford, UK
| | - William Yavo
- University Félix Houphouët-Boigny, Abidjan, Cote d'Ivoire,Malaria Research and Control Center of the National Institute of Public Health, Abidjan, Cote d'Ivoire
| | - Htut Ye
- Department of Medical Research, Yangon, Myanmar
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3
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Epstein JE, Tewari K, Lyke KE, Sim BKL, Billingsley PF, Laurens MB, Gunasekera A, Chakravarty S, James ER, Sedegah M, Richman A, Velmurugan S, Reyes S, Li M, Tucker K, Ahumada A, Ruben AJ, Li T, Stafford R, Eappen AG, Tamminga C, Bennett JW, Ockenhouse CF, Murphy JR, Komisar J, Thomas N, Loyevsky M, Birkett A, Plowe CV, Loucq C, Edelman R, Richie TL, Seder RA, Hoffman SL. Live Attenuated Malaria Vaccine Designed to Protect Through Hepatic CD8+ T Cell Immunity. Science 2011; 334:475-80. [PMID: 21903775 DOI: 10.1126/science.1211548] [Citation(s) in RCA: 384] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- J E Epstein
- U.S. Military Malaria Vaccine Program, Naval Medical Research Center, Silver Spring, MD 20910, USA
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4
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Lyke KE, Fernández-Viňa MA, Cao K, Hollenbach J, Coulibaly D, Kone AK, Guindo A, Burdett LA, Hartzman RJ, Wahl AR, Hildebrand WH, Doumbo OK, Plowe CV, Sztein MB. Association of HLA alleles with Plasmodium falciparum severity in Malian children. ACTA ACUST UNITED AC 2011; 77:562-71. [PMID: 21447146 PMCID: PMC3152196 DOI: 10.1111/j.1399-0039.2011.01661.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Pre-erythrocytic immunity to Plasmodium falciparum malaria is likely to be mediated by T-cell recognition of malaria epitopes presented on infected host cells via class I and II major histocompatibility complex (MHC) antigens. To test for associations of human leukocyte antigen (HLA) alleles with disease severity, we performed high-resolution typing of HLA class I and II loci and compared the distributions of alleles of HLA-A, -B, -C and -DRB1 loci in 359 Malian children of Dogon ethnicity with uncomplicated or severe malaria. We observed that alleles A*30:01 and A*33:01 had higher frequency in the group of patients with cerebral disease compared to patients with uncomplicated disease [A*30:01: gf = 0.2031 vs gf = 0.1064, odds ratio (OR) = 3.17, P = 0.004, confidence interval (CI) (1.94-5.19)] and [A*33:01: gf = 0.0781 vs gf = 0.0266, 4.21, P = 0.005, CI (1.89-9.84)], respectively. The A*30:01 and A*33:01 alleles share some sequence motifs and A*30:01 appears to have a unique peptide binding repertoire compared to other A*30 group alleles. Computer algorithms predicted malaria peptides with strong binding affinity for HLA-A*30:01 and HLA-A*33:01 but not to closely related alleles. In conclusion, we identified A*30:01 and A*33:01 as potential susceptibility factors for cerebral malaria, providing further evidence that polymorphism of MHC genes results in altered malaria susceptibility.
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Affiliation(s)
- K E Lyke
- Department of Medicine, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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5
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Abstract
The development of effective malaria vaccines may be hindered by extensive genetic diversity in the surface proteins being employed as vaccine antigens. Understanding of the extent and dynamics of genetic diversity in vaccine antigens is needed to guide rational vaccine design and to interpret the results of vaccine efficacy trials conducted in malaria endemic areas. Molecular epidemiological, population genetic, and structural approaches are being employed to try to identify immunologically relevant polymorphism in vaccine antigens. The results of these studies will inform choices of which alleles to include in multivalent or chimeric vaccines; however, additional molecular and immuno-epidemiological studies in a variety of geographic locations will be necessary for these approaches to succeed. Alternative means of overcoming antigenic diversity are also being explored, including boosting responses to critical conserved regions of current vaccine antigens, identifying new, more conserved and less immunodominant antigens, and developing whole-organism vaccines. Continued creative application and integration of tools from multiple disciplines, including epidemiology, immunology, molecular biology, and evolutionary genetics and genomics, will likely be required to develop broadly protective vaccines against Plasmodium and other antigenically complex pathogens.
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Affiliation(s)
- S L Takala
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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6
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Abstract
Combination drug therapy for malaria is recommended both to prevent and to overcome drug resistance. Drug combinations developed for use in Asia are being deployed in Africa, where higher rates of malaria affect the therapeutic and public health objectives of malaria chemotherapy as well as drug safety. Rational consideration of drug mechanisms, pharmacokinetics (PK), pharmacodynamics (PD), and malaria epidemiology should result in more effective combination regimens that retain therapeutic and prophylactic efficacy in the face of resistance.
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Affiliation(s)
- M M Nyunt
- Division of Clinical Pharmacology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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7
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Djimde AA, Kirkman L, Kassambara L, Diallo M, Plowe CV, Wellems TE, Doumbo OK. [In vitro cultivation of fields isolates of Plasmodium falciparum in Mali]. ACTA ACUST UNITED AC 2007; 100:3-5. [PMID: 17402683 DOI: 10.3185/pathexo2883] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Malaria immunology, molecular biology and pathogenicity studies often require the adaptation of Plasmodium falciparum field isolates to continuous in vitro cultivation. For this purpose we have established propagation protocols of asexual erythrocytic stages of P. falciparum samples from malaria patients or asymptomatic carriers in Mali. The parasites were grown in standard culture medium supplemented by human serum and in a culture medium without human serum but supplemented by AlbuMax 1. The candle jar environment and tissue culture flasks gassed with 5% CO2, 5% O2 and 90% N2 obtained from a portable gas mixer were used. Protocols for parasite cultivation in a resource-poor setting were developed. These protocols were successfully applied to fresh isolates in Mali as well as to blood samples frozen in liquid nitrogen and shipped to a laboratory in U.S.A.
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Affiliation(s)
- A A Djimde
- Centre de recherche et de formation sur le paludisme, Département d'épidemiologie des affections parasitaires, Faculté de medecine, de pharmacie et d'odonto-stomatologie, Université de Bamako, Mali.
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8
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Abstract
Despite the initiation in 1998 by the World Health Organization of a campaign to 'Roll Back Malaria', the rates of disease and death caused by Plasmodium falciparum malaria in sub-Saharan Africa are growing. Drug resistance has been implicated as one of the main factors in this disturbing trend. The efforts of international agencies, governments, public health officials, advocacy groups and researchers to devise effective strategies to deter the spread of drug resistant malaria and to ameliorate its heavy burden on the people of Africa have not succeeded. This review will not attempt to describe the regional distribution of drug resistant malaria in Africa in detail, mainly because information on resistance is limited and has been collected using different methods, making it difficult to interpret. Instead, the problems of defining and monitoring resistance and antimalarial drug treatment outcomes will be discussed in hopes of clarifying the issues and identifying ways to move forward in a more coordinated fashion. Strategies to improve measurement of resistance and treatment outcomes, collection and use of information on resistance, and potential approaches to deter and reduce the impact of resistance, will all be considered. The epidemiological setting and the goals of monitoring determine how antimalarial treatment responses should be measured. Longitudinal studies, with incidence of uncomplicated malaria episodes as the primary endpoint, provide the best information on which to base treatment policy changes, while simpler standard in vivo efficacy studies are better suited for ongoing efficacy monitoring. In the absence of an ideal antimalarial combination regimen, different treatment alternatives are appropriate in different settings. But where chloroquine has failed, policy changes are long overdue and action must be taken now.
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Affiliation(s)
- C V Plowe
- Malaria Section, Center for Vaccine Development, University of Maryland School of Medicine, 685 West Baltimore Street, HSF1-480, Baltimore, MA 21201, USA.
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9
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Lyke KE, Burges R, Cissoko Y, Sangare L, Dao M, Diarra I, Kone A, Harley R, Plowe CV, Doumbo OK, Sztein MB. Serum levels of the proinflammatory cytokines interleukin-1 beta (IL-1beta), IL-6, IL-8, IL-10, tumor necrosis factor alpha, and IL-12(p70) in Malian children with severe Plasmodium falciparum malaria and matched uncomplicated malaria or healthy controls. Infect Immun 2004; 72:5630-7. [PMID: 15385460 PMCID: PMC517593 DOI: 10.1128/iai.72.10.5630-5637.2004] [Citation(s) in RCA: 310] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Inflammatory cytokines play an important role in human immune responses to malarial disease. However, the role of these mediators in disease pathogenesis, and the relationship between host protection and injury remains unclear. A total of 248 cases of severe Plasmodium falciparum malaria among children aged 3 months to 14 years residing in Bandiagara, Mali, were matched to cases of uncomplicated malaria and healthy controls. Using modified World Health Organization criteria for defining severe malaria, we identified 100 cases of cerebral malaria (coma, seizure, and obtundation), 17 cases of severe anemia (hemoglobin, <5 g/dl), 18 cases combined cerebral malaria with severe anemia, and 92 cases with hyperparasitemia (asexual trophozoites, >500,000/mm3). Significantly elevated levels (given as geometric mean concentrations in picograms/milliliter) of interleukin-6 (IL-6; 485.2 versus 54.1; P = <0.001), IL-10 (1,099.3 versus 14.1; P = <0.001), tumor necrosis factor alpha (10.1 versus 7.7; P = <0.001), and IL-12(p70) (48.9 versus 31.3; P = 0.004) in serum were found in severe cases versus healthy controls. Significantly elevated levels of IL-6 (485.2 versus 141.0; P = <0.001) and IL-10 (1,099.3 versus 133.9; P = <0.001) were seen in severe malaria cases versus uncomplicated malaria controls. Cerebral malaria was associated with significantly elevated levels of IL-6 (754.5 versus 311.4; P = <0.001) and IL-10 (1,405.6 versus 868.6; P = 0.006) compared to severe malaria cases without cerebral manifestations. Conversely, lower levels of IL-6 (199.2 versus 487.6; P = 0.03) and IL-10 (391.1 versus 1,160.9; P = 0.002) were noted in children with severe anemia compared to severe malaria cases with hemoglobin at >5 g/dl. Hyperparasitemia was associated with significantly lower levels of IL-6 (336.6 versus 602.1; P = 0.002). These results illustrate the complex relationships between inflammatory cytokines and disease in P. falciparum malaria.
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Affiliation(s)
- K E Lyke
- Center for Vaccine Development, The University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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10
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Cao K, Moormann AM, Lyke KE, Masaberg C, Sumba OP, Doumbo OK, Koech D, Lancaster A, Nelson M, Meyer D, Single R, Hartzman RJ, Plowe CV, Kazura J, Mann DL, Sztein MB, Thomson G, Fernández-Viña MA. Differentiation between African populations is evidenced by the diversity of alleles and haplotypes of HLA class I loci. ACTA ACUST UNITED AC 2004; 63:293-325. [PMID: 15009803 DOI: 10.1111/j.0001-2815.2004.00192.x] [Citation(s) in RCA: 148] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The allelic and haplotypic diversity of the HLA-A, HLA-B, and HLA-C loci was investigated in 852 subjects from five sub-Saharan populations from Kenya (Nandi and Luo), Mali (Dogon), Uganda, and Zambia. Distributions of genotypes at all loci and in all populations fit Hardy-Weinberg equilibrium expectations. There was not a single allele predominant at any of the loci in these populations, with the exception of A*3002 [allele frequency (AF) = 0.233] in Zambians and Cw*1601 (AF = 0.283) in Malians. This distribution was consistent with balancing selection for all class I loci in all populations, which was evidenced by the homozygosity F statistic that was less than that expected under neutrality. Only in the A locus in Zambians and the C locus in Malians, the AF distribution was very close to neutrality expectations. There were six instances in which there were significant deviations of allele distributions from neutrality in the direction of balancing selection. All allelic lineages from each of the class I loci were found in all the African populations. Several alleles of these loci have intermediate frequencies (AF = 0.020-0.150) and seem to appear only in the African populations. Most of these alleles are widely distributed in the African continent and their origin may predate the separation of linguistic groups. In contrast to native American and other populations, the African populations do not seem to show extensive allelic diversification within lineages, with the exception of the groups of alleles A*02, A*30, B*57, and B*58. The alleles of human leukocyte antigen (HLA)-B are in strong linkage disequilibrium (LD) with alleles of the C locus, and the sets of B/C haplotypes are found in several populations. The associations between A alleles with C-blocks are weaker, and only a few A/B/C haplotypes (A*0201-B*4501-Cw*1601; A*2301-B*1503-Cw*0202; A*7401-B* 1503-Cw*0202; A*2902-B*4201-Cw*1701; A*3001-B*4201-Cw*1701; and A*3601-B*5301-Cw*0401) are found in multiple populations with intermediate frequencies [haplotype frequency (HF) = 0.010-0.100]. The strength of the LD associations between alleles of HLA-A and HLA-B loci and those of HLA-B and HLA-C loci was on average of the same or higher magnitude as those observed in other non-African populations for the same pairs of loci. Comparison of the genetic distances measured by the distribution of alleles at the HLA class I loci in the sub-Saharan populations included in this and other studies indicate that the Luo population from western Kenya has the closest distance with virtually all sub-Saharan population so far studied for HLA-A, a finding consistent with the putative origin of modern humans in East Africa. In all African populations, the genetic distances between each other are greater than those observed between European populations. The remarkable current allelic and haplotypic diversity in the HLA system as well as their variable distribution in different sub-Saharan populations is probably the result of evolutionary forces and environments that have acted on each individual population or in their ancestors. In this regard, the genetic diversity of the HLA system in African populations poses practical challenges for the design of T-cell vaccines and for the transplantation medical community to find HLA-matched unrelated donors for patients in need of an allogeneic transplant.
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Affiliation(s)
- K Cao
- Department of Oncology, Georgetown University, Washington, DC, USA
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11
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Moulds JM, Thomas BJ, Doumbo O, Diallo DA, Lyke KE, Plowe CV, Rowe JA, Birmingham DJ. Identification of the Kna/Knb polymorphism and a method for Knops genotyping. Transfusion 2004; 44:164-9. [PMID: 14962306 PMCID: PMC2877259 DOI: 10.1111/j.1537-2995.2004.00615.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND DNA mutations resulting in the McCoy and Swain-Langley polymorphisms have been identified on complement receptor 1 (CR1)-a ligand for rosetting of Plasmodium falciparum-infected RBCs. The molecular identification of the Kna/Knb polymorphism was sought to develop a genotyping method for use in the study of the Knops blood group and malaria. STUDY DESIGN AND METHODS CR1 deletion constructs were used in inhibition studies of anti-Kna. PCR amplification of Exon 29 was followed by DNA sequencing. A PCR-RFLP was developed with NdeI, BsmI, and MfeI for the detection of Kna/Knb, McCa/McCb, and Sl1/Sl2, respectively. Knops phenotypes were determined with standard serologic techniques. RESULTS A total of 310 Malian persons were phenotyped for Kna with 200 (64%) Kn(a+) and 110 (36%) Kn(a-). Many of the Kn(a-) exhibited the Knops-null phenotype, that is, Helgeson. The Kna/b DNA polymorphism was identified as a V1561M mutation with allele frequencies of Kna (V1561) 0.9 and Knb (M1561) 0.1. CONCLUSION The high frequency (18%) of Knb in West African persons suggests that it is not solely a Caucasian trait. Furthermore, because of the high incidence of heterozygosity as well as amorphs, accurate Knops typing of donors of African descent is best accomplished by a combination of molecular and serologic techniques.
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Affiliation(s)
- J M Moulds
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129, USA.
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12
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Rowe JA, Raza A, Diallo DA, Baby M, Poudiougo B, Coulibaly D, Cockburn IA, Middleton J, Lyke KE, Plowe CV, Doumbo OK, Moulds JM. Erythrocyte CR1 expression level does not correlate with a HindIII restriction fragment length polymorphism in Africans; implications for studies on malaria susceptibility. Genes Immun 2002; 3:497-500. [PMID: 12486610 DOI: 10.1038/sj.gene.6363899] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2002] [Accepted: 04/25/2002] [Indexed: 01/10/2023]
Abstract
Complement receptor 1 (CR1) expression level on erythrocytes is genetically determined, and in Caucasian populations is linked to high (H) and low (L) expression alleles identified by a HindIII restriction fragment length polymorphism (RFLP). Erythrocyte CR1 may be an important factor in determining malaria susceptibility, as low expression of CR1 reduces the rosetting of uninfected erythrocytes with Plasmodium falciparum-infected cells, a process that contributes to malaria pathogenesis. Prior to studying CR1 expression and malaria susceptibility, we have investigated whether the quantity of erythrocyte CR1 correlates with the H and L alleles in an African population. Mean erythrocyte CR1 in 149 Malian adults was 415 molecules per cell, which is comparable to Caucasian populations; however, there was no relationship between erythrocyte CR1 level and genotype for the HindIII RFLP (mean CR1 per erythrocyte HH = 414, HL = 419 and LL = 403, P > 0.1, Student's t-test). The conclusions of a previous study of erythrocyte CR1 expression level and malaria susceptibility in West Africa that was based on HindIII RFLP genotyping may therefore need to be re-evaluated.
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Affiliation(s)
- J A Rowe
- Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, UK.
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13
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Sulo J, Chimpeni P, Hatcher J, Kublin JG, Plowe CV, Molyneux ME, Marsh K, Taylor TE, Watkins WM, Winstanley PA. Chlorproguanil-dapsone versus sulfadoxine-pyrimethamine for sequential episodes of uncomplicated falciparum malaria in Kenya and Malawi: a randomised clinical trial. Lancet 2002; 360:1136-43. [PMID: 12387962 DOI: 10.1016/s0140-6736(02)11198-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Chlorproguanil-dapsone exerts lower resistance pressure on Plasmodium falciparum than does sulfadoxine-pyrimethamine, but is rapidly eliminated. We aimed to find out whether chlorproguanil-dapsone results in a higher retreatment rate for malaria than sulfadoxine-pyrimethamine. METHODS In a randomised trial of paediatric outpatients with uncomplicated falciparum malaria, patients received either chlorproguanil-dapsone or sulfadoxine-pyrimethamine and were followed up for up to 1 year. Sites were in Kenya (n=410) and Malawi (n=500). We used per-protocol analysis to assess the primary outcome of annual malaria incidence. FINDINGS Drop-outs were 117 of 410 (28.5%) in Kenya, and 342 of 500 (68.4%) in Malawi. Follow-up was for a median of 338 days (IQR 128-360) and 342 days (152-359) in Kilifi (chlorproguanil-dapsone and sulfadoxine-pyrimethamine, respectively), and for 120 days (33-281) and 84 days (26-224) in Blantyre. Mean annual malaria incidence was 2.5 versus 2.1 in Kenya (relative risk 1.16, 95% CI 0.98-1.37), and 2.2 versus 2.8 in Malawi (0.77, 0.63-0.94). 4.3% versus 12.8%, and 5.4% versus 20.1%, of patients were withdrawn for treatment failure in Kenya and Malawi, respectively. In Kenya haemoglobin concentration of 50 g/L or less caused exit in 6.9% of chlorproguanil-dapsone patients and 1.5% of sulfadoxine-pyrimethamine patients, but most anaemia occurred before re-treatment. In Malawi only one patient exited because of anaemia. INTERPRETATION Despite the rapid elimination of chlorproguanil-dapsone, children treated with this drug did not have a higher incidence of malaria episodes than those treated with sulfadoxine-pyrimethamine. Treatment failure was more common with sulfadoxine-pyrimethamine. Cause of anaemia in Kenya was probably not adverse reaction to chlorproguanil-dapsone, but this observation requires further study.
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Affiliation(s)
- J Sulo
- Centre for Geographical Medicine, Kenya Medical Research Institute, Kilifi, Kenya
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Sibley CH, Hyde JE, Sims PF, Plowe CV, Kublin JG, Mberu EK, Cowman AF, Winstanley PA, Watkins WM, Nzila AM. Pyrimethamine-sulfadoxine resistance in Plasmodium falciparum: what next? Trends Parasitol 2001; 17:582-8. [PMID: 11756042 DOI: 10.1016/s1471-4922(01)02085-2] [Citation(s) in RCA: 252] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Chemotherapy remains the only practicable tool to control falciparum malaria in sub-Saharan Africa, where >90% of the world's burden of malaria mortality and morbidity occurs. Resistance is rapidly eroding the efficacy of chloroquine, and the combination pyrimethamine-sulfadoxine is the most commonly chosen alternative. Resistant populations of Plasmodium falciparum were selected extremely rapidly in Southeast Asia and South America. If this happens in sub-Saharan Africa, it will be a public health disaster because no inexpensive alternative is currently available. This article reviews the molecular mechanisms of this resistance and discusses how to extend the therapeutic life of antifolate drugs.
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Affiliation(s)
- C H Sibley
- Department of Genetics, Box 357360, University of Washington, Seattle, WA 98195-7360, USA.
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15
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Abstract
Trimethoprim-sulfamethoxazole has been recommended as part of the standard package of care for people with HIV and AIDS in Africa. A similar antifolate combination, sulfadoxine-pyrimethamine, is now the first-line antimalarial drug in several of the African countries with the highest rates of HIV infection. We present evidence of Plasmodium falciparum cross-resistance between trimethoprim and pyrimethamine at the molecular level. The impact of trimethoprim-sulfamethoxazole on the efficacy of sulfadoxine-pyrimethamine needs to be assessed urgently, and alternative antimalarial treatment should be considered for people on trimethoprim-sulfamethoxazole prophylaxis.
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Abstract
The development of chloroquine as an antimalarial drug and the subsequent evolution of drug-resistant Plasmodium strains had major impacts on global public health in the 20th century. In P. falciparum, the cause of the most lethal human malaria, chloroquine resistance is linked to multiple mutations in PfCRT, a protein that likely functions as a transporter in the parasite's digestive vacuole membrane. Rapid diagnostic assays for PfCRT mutations are already employed as surveillance tools for drug resistance. Here, we review recent field studies that support the central role of PfCRT mutations in chloroquine resistance. These studies suggest chloroquine resistance arose in > or = 4 distinct geographic foci and substantiate an important role of immunity in the outcomes of resistant infections after chloroquine treatment. P. vivax, which also causes human malaria, appears to differ from P. falciparum in its mechanism of chloroquine resistance. Investigation of the resistance mechanisms and of the role of immunity in therapeutic outcomes will support new approaches to drugs that can take the place of chloroquine or augment its efficiency.
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Affiliation(s)
- T E Wellems
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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17
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18
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Carlton JM, Fidock DA, Djimdé A, Plowe CV, Wellems TE. Conservation of a novel vacuolar transporter in Plasmodium species and its central role in chloroquine resistance of P. falciparum. Curr Opin Microbiol 2001; 4:415-20. [PMID: 11495804 DOI: 10.1016/s1369-5274(00)00228-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Chloroquine resistance in Plasmodium falciparum has recently been shown to result from mutations in the novel vacuolar transporter, PfCRT. Field studies have demonstrated the importance of these mutations in clinical resistance. Although a pfcrt ortholog has been identified in Plasmodiumvivax, there is no association between in vivo chloroquine resistance and codon mutations in the P. vivax gene. This is consistent with lines of evidence that suggest alternative mechanisms of chloroquine resistance among various malaria parasite species.
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Affiliation(s)
- J M Carlton
- National Center for Biotechnology Research, National Library of Medicine, National Institutes of Health, Building 45, 45 Center Drive, Bethesda, MD 20892-6510, USA
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19
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Plowe CV, Doumbo OK, Djimde A, Kayentao K, Diourte Y, Doumbo SN, Coulibaly D, Thera M, Wellems TE, Diallo DA. Chloroquine treatment of uncomplicated Plasmodium falciparum malaria in Mali: parasitologic resistance versus therapeutic efficacy. Am J Trop Med Hyg 2001; 64:242-6. [PMID: 11463110 DOI: 10.4269/ajtmh.2001.64.242] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Whether and when to replace chloroquine with other antimalarial drugs is an urgent public health question in much of Africa, where Plasmodium falciparum, which is increasingly resistant to chloroquine, continues to kill millions each year. Antimalarial drug efficacy has traditionally been measured as parasitologic resistance, but recent guidelines use both clinical and parasitologic criteria to monitor therapeutic efficacy. To assess the new efficacy protocol, we measured parasitologic and therapeutic outcomes in 514 patients treated with chloroquine for uncomplicated P. falciparum malaria in Mali. There was a general agreement between parasitologic and therapeutic outcomes at two sites, with 13-17% parasitologic resistance rates and 10-15% treatment failure rates. However, the new protocol overestimated early treatment failure rates (21-71% of cases classified as early treatment failure had sensitive or RI parasitologic responses), particularly where resistance was rare, and missed low-level parasitologic resistance. Modifications of the protocol for monitoring antimalarial therapeutic efficacy are recommended.
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Affiliation(s)
- C V Plowe
- Center for Vaccine Development, Department of Medicine, University of Maryland School of Medicine, Baltimore 21201, USA.
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20
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Salcedo E, Cortese JF, Plowe CV, Sims PF, Hyde JE. A bifunctional dihydrofolate synthetase--folylpolyglutamate synthetase in Plasmodium falciparum identified by functional complementation in yeast and bacteria. Mol Biochem Parasitol 2001; 112:239-52. [PMID: 11223131 DOI: 10.1016/s0166-6851(00)00370-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Folate metabolism in the human malaria parasite Plasmodium falciparum is an essential activity for cell growth and replication, and the target of an important class of therapeutic agents in widespread use. However, resistance to antifolate drugs is a major health problem in the developing world. To date, only two activities in this complex pathway have been targeted by antimalarials. To more fully understand the mechanisms of antifolate resistance and to identify promising targets for new chemotherapies, we have cloned genes encoding as yet uncharacterised enzymes in this pathway. By means of complementation experiments using 1-carbon metabolism mutants of both Escherichia coli and Saccharomyces cerevisiae, we demonstrate here that one of these parasite genes encodes both dihydrofolate synthetase (DHFS) and folylpolyglutamate synthetase (FPGS) activities, which catalyse the synthesis and polyglutamation of folate derivatives, respectively. The malaria parasite is the first known example of a eukaryote encoding both DHFS and FPGS activities in a single gene. DNA sequencing of this gene in antifolate-resistant strains of P. falciparum, as well as drug-inhibition assays performed on yeast and bacteria expressing PfDHFS--FPGS, indicate that current antifolate regimes do not target this enzyme. As PfDHFS--FPGS harbours two activities critical to folate metabolism, one of which has no human counterpart, this gene product offers a novel chemotherapeutic target with the potential to deliver a powerful blockage to parasite growth.
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Affiliation(s)
- E Salcedo
- Department of Biomolecular Sciences, University of Manchester Institute of Science and Technology, PO Box 88, Manchester M60 1QD, UK
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21
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Djimdé A, Doumbo OK, Cortese JF, Kayentao K, Doumbo S, Diourté Y, Coulibaly D, Dicko A, Su XZ, Nomura T, Fidock DA, Wellems TE, Plowe CV. A molecular marker for chloroquine-resistant falciparum malaria. N Engl J Med 2001; 344:257-63. [PMID: 11172152 DOI: 10.1056/nejm200101253440403] [Citation(s) in RCA: 693] [Impact Index Per Article: 30.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Chloroquine-resistant Plasmodium falciparum malaria is a major health problem, particularly in sub-Saharan Africa. Chloroquine resistance has been associated in vitro with point mutations in two genes, pfcrt and pfmdr 1, which encode the P. falciparum digestive-vacuole transmembrane proteins PfCRT and Pgh1, respectively. METHODS To assess the value of these mutations as markers for clinical chloroquine resistance, we measured the association between the mutations and the response to chloroquine treatment in patients with uncomplicated falciparum malaria in Mali. The frequencies of the mutations in patients before and after treatment were compared for evidence of selection of resistance factors as a result of exposure to chloroquine. RESULTS The pfcrt mutation resulting in the substitution of threonine (T76) for lysine at position 76 was present in all 60 samples from patients with chloroquine-resistant infections (those that persisted or recurred after treatment), as compared with a base-line prevalence of 41 percent in samples obtained before treatment from 116 randomly selected patients (P<0.001), indicating absolute selection for this mutation. The pfmdr 1 mutation resulting in the substitution of tyrosine for asparagine at position 86 was also selected for, since it was present in 48 of 56 post-treatment samples from patients with chloroquine-resistant infections (86 percent), as compared with a base-line prevalence of 50 percent in 115 samples obtained before treatment (P<0.001). The presence of pfcrt T76 was more strongly associated with the development of chloroquine resistance (odds ratio, 18.8; 95 percent confidence interval, 6.5 to 58.3) than was the presence of pfmdr 1 Y86 (odds ratio, 3.2; 95 percent confidence interval, 1.5 to 6.8) or the presence of both mutations (odds ratio, 9.8; 95 percent confidence interval, 4.4 to 22.1). CONCLUSIONS This study shows an association between the pfcrt T76 mutation in P. falciparum and the development of chloroquine resistance during the treatment of malaria. This mutation can be used as a marker in surveillance for chloroquine-resistant falciparum malaria.
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Affiliation(s)
- A Djimdé
- Malaria Section, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore 21201, USA
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22
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Agarwal A, Guindo A, Cissoko Y, Taylor JG, Coulibaly D, Koné A, Kayentao K, Djimde A, Plowe CV, Doumbo O, Wellems TE, Diallo D. Hemoglobin C associated with protection from severe malaria in the Dogon of Mali, a West African population with a low prevalence of hemoglobin S. Blood 2000; 96:2358-63. [PMID: 11001883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
The malaria hypothesis proposes a survival advantage for individuals with hemoglobin variants in areas of endemic Plasmodium falciparum malaria. Hemoglobin C (HbC) is a possible example in West Africa, where this hemoglobin has a centric distribution with high frequencies among certain populations including the Dogon ethnic group. To test whether HbC is associated with protection from malaria, we performed a case-control study in the Dogon of Bandiagara, Mali. HbC was present in 68 of 391 (17.4%) of uncomplicated malaria control cases, whereas it was detected in only 3 of 67 cases (4.5%) of severe malaria (odds ratio [OR], 0.22; P =. 01). Further, HbC was present in only 1 of 34 cases (2.9%) with cerebral manifestations, the most common presentation of severe malaria in this population (OR, 0.14; P =.03). Episodes of uncomplicated malaria and parasitemias (4800-205 050/microL) were identified in cases of homozygous HbC (HbCC), which indicates that P falciparum parasites are able to efficiently replicate within HbCC erythrocytes in vivo. These findings suggest that HbC does not protect against infection or uncomplicated malaria but can protect against severe malaria in the Dogon population of Bandiagara, Mali. The data also suggest that the protective effect associated with HbC may be greater than that of HbS in this population.
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Affiliation(s)
- A Agarwal
- National Institute of Allergy and Infectious Diseases and the National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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23
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Vasconcelos KF, Plowe CV, Fontes CJ, Kyle D, Wirth DF, Pereira da Silva LH, Zalis MG. Mutations in Plasmodium falciparum dihydrofolate reductase and dihydropteroate synthase of isolates from the Amazon region of Brazil. Mem Inst Oswaldo Cruz 2000; 95:721-8. [PMID: 10998224 DOI: 10.1590/s0074-02762000000500020] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Since the late 1970s pyrimethamine-sulfadoxine (PS; FansidarTM Hoffman-LaRoche, Basel) has been used as first line therapy for uncomplicated malaria in the Amazon basin. Unfortunately, resistance has developed over the last ten years in many regions of the Amazon and PS is no longer recommended for use in Brazil. In vitro resistance to pyrimethamine and cycloguanil (the active metabolite of proguanil) is caused by specific point mutations in Plasmodium falciparum dihydrofolate reductase (DHFR), and in vitro resistance to sulfadoxine has been associated with mutations in dihydropteroate synthase (DHPS). In association with a proguanil-sulfamethoxazole clinical trial in Brazil, we performed a nested mutation-specific polymerase chain reaction to measure the prevalence of DHFR mutations at codons 50, 51, 59, 108 and 164 and DHPS mutations at codons 436, 437, 540, 581 and 613 at three sites in the Brazilian Amazon. Samples from two isolated towns showed a high degree of homogeneity, with the DHFR Arg-50/Ile-51/Asn-108 and DHPS Gly-437/Glu-540/Gly-581 mutant genotype accounting for all infections in Peixoto de Azevedo (n = 15) and 60% of infections in Apiacás (n = 10), State of Mato Grosso. The remaining infections in Apiacás differed from this predominant genotype only by the addition of the Bolivia repeat at codon 30 and the Leu-164 mutation in DHFR. By contrast, 17 samples from Porto Velho, capital city of the State of Rondônia, with much in- and out-migration, showed a wide variety of DHFR and DHPS genotypes.
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Affiliation(s)
- K F Vasconcelos
- Laboratório de Biologia da Malária, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 21949-900, Brasil
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24
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Doumbo OK, Kayentao K, Djimde A, Cortese JF, Diourte Y, Konaré A, Kublin JG, Plowe CV. Rapid selection of Plasmodium falciparum dihydrofolate reductase mutants by pyrimethamine prophylaxis. J Infect Dis 2000; 182:993-6. [PMID: 10950805 DOI: 10.1086/315787] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2000] [Revised: 06/08/2000] [Indexed: 11/03/2022] Open
Abstract
A prospective study was conducted to measure the selective effect of pyrimethamine prophylaxis on point mutations in Plasmodium falciparum dihydrofolate reductase (DHFR). A total of 109 Malian children were given pyrimethamine weekly for 5 weeks. P. falciparum infections were analyzed by polymerase chain reaction for DHFR mutations, which were dramatically more frequent among prophylaxis-breakthrough infections than at baseline: the prevalence of Asn-108 rose from 13% to 100%, Ile-51 from 4% to 50%, and Arg-59 from 11% to 90%. Eight persistent infections lacking detectable DHFR mutations at baseline developed multiple mutations within 1 week of the patients' starting pyrimethamine prophylaxis. Microsatellite analysis found no evidence of clonal identity among baseline and breakthrough infections. Analysis of these data demonstrates that under prophylaxis conditions, pyrimethamine is strongly selective for DHFR mutations, which arise extremely rapidly under drug pressure, even when undetectable in the initial infection. These findings have implications for prophylaxis regimens with other antifolate drugs.
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Affiliation(s)
- O K Doumbo
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy, and Odonto-stomatology, University of Mali, Bamako, Mali
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25
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Affiliation(s)
- W M Watkins
- Kenya Medical Research Institute (KEMRI), Nairobi, Kenya and the Wellcome Trust Research Laboratories, Nairobi, Kenya.
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26
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Diourté Y, Djimdé A, Doumbo OK, Sagara I, Coulibaly Y, Dicko A, Diallo M, Diakité M, Cortese JF, Plowe CV. Pyrimethamine-sulfadoxine efficacy and selection for mutations in Plasmodium falciparum dihydrofolate reductase and dihydropteroate synthase in Mali. Am J Trop Med Hyg 1999; 60:475-8. [PMID: 10466980 DOI: 10.4269/ajtmh.1999.60.475] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
To assess pyrimethamine-sulfadoxine (PS) efficacy in Mali, and the role of mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) in in vivo PS resistance, 190 patients with uncomplicated P. falciparum malaria were treated with PS and monitored for 56 days. Mutation-specific polymerase chain reactions and digestion with restriction endonucleases were used to detect DHFR and DHPS mutations on filter paper blood samples from pretreatment and post-treatment infections. Only one case each of RI and RII level resistance and no cases of RIII resistance or therapeutic failure were observed. Post-PS treatment infections had significantly higher rates of DHFR mutations at codons 108 and 59. No significant selection for DHPS mutations was seen. Pyrimethamine-sulfadoxine is highly efficacious in Mali, and while the low level of resistance precludes assessing the utility of molecular assays for in vivo PS resistance, rapid selection of DHFR mutations supports their role in PS failure.
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Affiliation(s)
- Y Diourté
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odontostomatology, Bamako, Mali
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27
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Abstract
Inappropriate use of antimalarial drugs undermines therapeutic efficacy and promotes the emergence and spread of drug-resistant malaria. Strategies for improving compliance require accurate information about current practices. Here we describe Knowledge-Attitude-Practice surveys conducted among health providers and consumers in two Malian villages, one rural and one periurban. All sanctioned providers limited their first choices of antimalarial drug to those recommended by the national malaria control program and reported using correct dosing regimens. However, the majority of consumers in the two villages chose non-recommended treatments for malaria and reported suboptimal treatment regimens when they did use recommended drugs. Antimalarial drugs were also widely available from unsanctioned sources, often accompanied by erroneous advice on dosing regimens. This study demonstrates that even when the most peripheral health providers are well-trained in correct use of antimalarial drugs, additional measures directly targeting consumers will be required to improve drug use practices.
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Affiliation(s)
- A Djimde
- Division of Geographic Medicine, University of Maryland School of Medicine, Baltimore 21201, USA
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28
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Abstract
Two new dihydrofolate reductase (DHFR) mutations were recently discovered in Plasmodium falciparum samples from an area of Bolivia with high rates of in vivo resistance to pyrimethamine-sulfadoxine: a Cys-->Arg point mutation in codon 50 and a five amino acid insertion after codon 30, termed the Bolivia repeat. We used a yeast expression system to screen these new DHFR mutants, as well as all of the other known DHFR mutant genotypes, against four antifolates: pyrimethamine, cycloguanil, chlorcycloguanil, and WR99210. The prodrug proguanil was also evaluated. The primary 108-Asn mutation, the known secondary mutations 51-Ile, 59-Arg and 164-Leu, as well as the 50-Arg mutation, all progressively enhanced pyrimethamine resistance in naturally observed combinations with one another, with the presence of 164-Leu most significantly increasing resistance. Cycloguanil and chlorcycloguanil resistance were most impacted by 164-Leu and the paired 16-Val/108-Thr. Proguanil had no effect on malaria DHFR. All DHFRs analyzed were sensitive to WR99210. The Bolivia repeat did not markedly affect drug sensitivity. We conclude that malaria DHFR can be reliably, rapidly and inexpensively analyzed in yeast for activity against a broad spectrum of antifolates. This system may be useful for initially characterizing newly discovered genotypes before proceeding to P. falciparum transfection; for large-scale geographic surveys of drug resistance; and for screening new antifolates or new antifolate combinations for their effectiveness against a large panel of DHFR mutants.
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Affiliation(s)
- J F Cortese
- Department of Medicine, University of Maryland School of Medicine, Baltimore 21201, USA
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29
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30
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Perry RT, Plowe CV, Koumaré B, Bougoudogo F, Kotloff KL, Losonsky GA, Wasserman SS, Levine MM. A single dose of live oral cholera vaccine CVD 103-HgR is safe and immunogenic in HIV-infected and HIV-noninfected adults in Mali. Bull World Health Organ 1998; 76:63-71. [PMID: 9615498 PMCID: PMC2305629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Despite considerable experience with single-dose, live, oral cholera vaccine CVD 103-HgR in Asia, Europe, and the Americas, the vaccine had not been evaluated in sub-Saharan Africa or on individuals infected with human immunodeficiency virus (HIV). We therefore conducted a randomized, placebo-controlled, double-blind, cross-over clinical trial in 38 HIV-seropositive (without clinical acquired immunodeficiency syndrome (AIDS)) and 387 HIV-seronegative adults in Mali to assess its safety and immunogenicity. Adverse reactions (fever, diarrhoea and vomiting) were observed with similar frequency among vaccine and placebo recipients. The vaccine strain was not isolated from the coprocultures of any subject. The baseline geometric mean titre (GMT) of serum vibriocidal antibody was significantly lower in HIV-seropositives (1:23) than in HIV-seronegatives (1:65) (P = 0.002). Significant rises in vibriocidal antibody were observed in 71% of HIV-seronegatives and 58% of HIV-seropositives, and in 40% of HIV-seropositives with CD4+ counts below 500 per microliter. Following immunization, the peak vibriocidal GMT in HIV-seronegatives was 1:584 versus 1:124 in HIV-seropositives (P = 0.0006); in HIV-seropositives with CD4+ counts < 500 per microliter, the peak vibriocidal GMT was 1:40 (P = 0.03 versus other HIV-seropositives). CVD 103-HgR was safe in HIV-infected Malian adults, although serological responses were significantly attenuated among HIV-seropositives (particularly in those with CD4+ counts < 500 per microliter) relative to HIV-seronegatives. These results encourage further evaluations of this single-dose, oral cholera vaccine in high-risk populations such as refugees in sub-Saharan Africa.
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Affiliation(s)
- R T Perry
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, USA
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31
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Plowe CV, Kublin JG, Doumbo OK. P. falciparum dihydrofolate reductase and dihydropteroate synthase mutations: epidemiology and role in clinical resistance to antifolates. Drug Resist Updat 1998; 1:389-96. [PMID: 17092820 DOI: 10.1016/s1368-7646(98)80014-9] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/1998] [Revised: 10/19/1998] [Accepted: 10/20/1998] [Indexed: 11/24/2022]
Abstract
Plasmodium falciparum resistance to the antifolates has arisen rapidly in Asia and South America, and threatens the usefulness of these drugs in Africa. In vitro resistance to the antifolates is determined by mutations in parasite dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS). The role of DHFR and DHPS mutations in therapeutic failure of antifolate antimalarials is less clear. This review summarizes molecular epidemiological surveys, studies of in vivo selection of mutant alleles by drug treatment, and prospective studies of the ability of mutation-specific assays to predict clinical outcomes, and discusses the potential use of these assays for surveillance of resistance.
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Affiliation(s)
- C V Plowe
- Molecular Parasitology and Malaria Field Studies Unit, Center for Vaccine Development/Division of Geographic Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
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32
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Nzila-Mounda A, Mberu EK, Sibley CH, Plowe CV, Winstanley PA, Watkins WM. Kenyan Plasmodium falciparum field isolates: correlation between pyrimethamine and chlorcycloguanil activity in vitro and point mutations in the dihydrofolate reductase domain. Antimicrob Agents Chemother 1998; 42:164-9. [PMID: 9449279 PMCID: PMC105474 DOI: 10.1128/aac.42.1.164] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Sixty-nine Kenyan Plasmodium falciparum field isolates were tested in vitro against pyrimethamine (PM), chlorcycloguanil (CCG), sulfadoxine (SD), and dapsone (DDS), and their dihydrofolate reductase (DHFR) genotypes were determined. The in vitro data show that CCG is more potent than PM and that DDS is more potent than SD. DHFR genotype is correlated with PM and CCG drug response. Isolates can be classified into three distinct groups based on their 50% inhibitory concentrations (IC50s) for PM and CCG (P < 0.01) and their DHFR genotypes. The first group consists of wild-type isolates with mean PM and CCG IC50s of 3.71 +/- 6.94 and 0.24 +/- 0.21 nM, respectively. The second group includes parasites which all have mutations at codon 108 alone or also at codons 51 or 59 and represents one homogeneous group for which 25- and 6-fold increases in PM and CCG IC50s, respectively, are observed. Parasites with mutations at codons 108, 51, and 59 (triple mutants) form a third distinct group for which nine- and eightfold increases in IC50s, respectively, of PM and CCG compared to the second group are observed. Surprisingly, there is a significant decrease (P < 0.01) of SD and DDS susceptibility in these triple mutants. Our data show that more than 92% of Kenyan field isolates have undergone at least one point mutation associated with a decrease in PM activity. These findings are of great concern because they may indicate imminent PM-SD failure, and there is no affordable antimalarial drug to replace PM-SD (Fansidar).
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Affiliation(s)
- A Nzila-Mounda
- Wellcome Trust Research Laboratories, Kenya Medical Research Institute, Nairobi.
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33
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Watkins WM, Mberu EK, Winstanley PA, Plowe CV. The efficacy of antifolate antimalarial combinations in Africa: a predictive model based on pharmacodynamic and pharmacokinetic analyses. ACTA ACUST UNITED AC 1997; 13:459-64. [PMID: 15275132 DOI: 10.1016/s0169-4758(97)01124-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
At present, effective treatment for non-severe malaria is the most important malaria control strategy in Africa. Pyrimethamine-sulfadoxine (PSD) is rapidly becoming the first-line treatment in areas of chloroquine resistance, although the parasite chemoresistance factors that dispose towards clinical failure with PSD are still unclear. Here, Bill Watkins and colleagues analyse the relationship between the pharmacokinetic properties of two treatment combinations (PSD and chlorproguanil-dapsone) in vivo and the respective in vitro isobolograms for parasites with specific drug-resistance patterns. From this relationship, they develop a hypothesis that may explain clinical drug failure and differential efficacy between treatments. The deductions can be tested in field studies to validate or refute the model.
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Affiliation(s)
- W M Watkins
- Department of Pharmacology and Therapeutics, University of Liverpool, UK.
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Plowe CV, Cortese JF, Djimde A, Nwanyanwu OC, Watkins WM, Winstanley PA, Estrada-Franco JG, Mollinedo RE, Avila JC, Cespedes JL, Carter D, Doumbo OK. Mutations in Plasmodium falciparum dihydrofolate reductase and dihydropteroate synthase and epidemiologic patterns of pyrimethamine-sulfadoxine use and resistance. J Infect Dis 1997; 176:1590-6. [PMID: 9395372 DOI: 10.1086/514159] [Citation(s) in RCA: 283] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
To assess the relationship between mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) and clinical pyrimethamine-sulfadoxine resistance, polymerase chain reaction surveys and analyses for new mutations were conducted in four countries with increasing levels of pyrimethamine-sulfadoxine resistance: Mali, Kenya, Malawi, and Bolivia. Prevalence of mutations at DHFR codon 108 and a new mutation at DHPS 540 correlated with increased pyrimethamine-sulfadoxine resistance (P < .05). Mutations at DHFR 51, DHFR 59, and DHPS 437 correlated with resistance without achieving statistical significance. Mutations at DHFR 164 and DHPS 581 were common in Bolivia, where pyrimethamine-sulfadoxine resistance is widespread, but absent in African sites. Two new DHFR mutations, a point mutation at codon 50 and an insert at codon 30, were found only in Bolivia. DHFR and DHPS mutations occur in a progressive, stepwise fashion. Identification of specific sets of mutations causing in vivo drug failure may lead to the development of molecular surveillance methods for pyrimethamine-sulfadoxine resistance.
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Affiliation(s)
- C V Plowe
- Department of Medicine, University of Maryland School of Medicine, Baltimore 21201, USA
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Plowe CV, Djimde A, Wellems TE, Diop S, Kouriba B, Doumbo OK. Community pyrimethamine-sulfadoxine use and prevalence of resistant Plasmodium falciparum genotypes in Mali: a model for deterring resistance. Am J Trop Med Hyg 1996; 55:467-71. [PMID: 8940973 DOI: 10.4269/ajtmh.1996.55.467] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Pyrimethamine-sulfadoxine (PS, Fansidar; Hoffman-LaRoche, Basel, Switzerland) is now the first-line antimalarial therapy in parts of Africa with high rates of chloroquine-resistant Plasmodium falciparum. With PS resistance increasing and no suitably inexpensive and effective third antimalarial drug available, strategies for delaying the spread of PS resistance in Africa are needed. Community PS usage was measured in two Malian villages, one rural and one periurban, and prevalence of pyrimethamine-resistant P. falciparum genotypes was determined at these sites and two urban sites. The prevalence of resistant genotypes was 22.6% (n = 84) in the periurban village where PS was available from multiple sources and large stocks of PS were observed, and 13.5% (n = 89) and 23.4% (n = 77) in a large town and a city, respectively, where PS is widely available. No pyrimethamine-resistant genotypes (n = 58) were detected in Kolle, a rural village with a community-supported dispensary and clinic where PS is used sparingly and no PS was available in pharmacies or markets. The high rates of pyrimethamine resistant genotypes concurrent with higher PS usage argue for a policy of judicious PS use in Mali and in similar settings. A possible model for slowing the spread of drug-resistant malaria is illustrated by the example of the Kolle clinic.
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Affiliation(s)
- C V Plowe
- Department of Medicine, University of Maryland School of Medicine, Baltimore, USA
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36
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Plowe CV, Djimde A, Bouare M, Doumbo O, Wellems TE. Pyrimethamine and proguanil resistance-conferring mutations in Plasmodium falciparum dihydrofolate reductase: polymerase chain reaction methods for surveillance in Africa. Am J Trop Med Hyg 1995; 52:565-8. [PMID: 7611566 DOI: 10.4269/ajtmh.1995.52.565] [Citation(s) in RCA: 454] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
As chloroquine resistance spreads across Africa, the dihydrofolate reductase (DHFR) inhibitors pyrimethamine and proguanil are being used as alternative first-line drugs for the treatment and prevention of Plasmodium falciparum malaria. Resistance to these drugs is conferred by point mutations in parasite DHFR. These point mutations can be detected by polymerase chain reaction (PCR) assays, but better methods for sample collection, DNA extraction, and a diagnostic PCR are needed to make these assays useful in malaria-endemic areas. Here we report methods for collecting fingerstick blood onto filter paper strips that are air-dried, then stored and transported at room temperature. Cell lysis and DNA extraction are accomplished by boiling in Chelex-100. We also report a nested PCR technique that has improved sensitivity and specificity. These procedures readily detect mixed infections of parasites with both sensitive and resistant genotypes (confirmed by direct sequencing) and are reliable at parasite densities less than 250/mm3 in field surveys.
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Affiliation(s)
- C V Plowe
- Malaria Research and Training Center, National School of Medicine and Pharmacy, Bamaka, Mali
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Affiliation(s)
- C V Plowe
- Laboratory of Malaria Research, National Institute of Allergy & Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
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Vaidya AB, Morrisey J, Plowe CV, Kaslow DC, Wellems TE. Unidirectional dominance of cytoplasmic inheritance in two genetic crosses of Plasmodium falciparum. Mol Cell Biol 1993; 13:7349-57. [PMID: 8246955 PMCID: PMC364805 DOI: 10.1128/mcb.13.12.7349-7357.1993] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Malarial parasites have two highly conserved cytoplasmic DNA molecules: a 6-kb tandemly arrayed DNA that has characteristics of a mitochondrial genome, and a 35-kb circular DNA that encodes functions commonly found in chloroplasts. We examined the inheritance pattern of these elements in two genetic crosses of Plasmodium falciparum clones. Parent-specific oligonucleotide probes and single-strand conformation polymorphism analysis identified single nucleotide changes that distinguished the parental 6- and 35-kb DNA molecules in the progeny. In all 16 independent recombinant progeny of a cross between a Central American clone, HB3, and a Southeast Asian clone, Dd2, the 6- and 35-kb DNAs were inherited from the Dd2 parent. In all nine independent recombinant progeny of a cross between clone HB3 and a likely African clone, 3D7, the 6-kb DNA was inherited from the 3D7 parent. Inheritance of cytoplasmic genomes of the Dd2 and 3D7 parents was, therefore, dominant over that of the HB3 parent. Cytoplasmic DNA molecules were found almost exclusively in the female gametes of malarial parasites; hence, clone HB3 did not appear to have served as a maternal parent for the progeny of two crosses. Defective differentiation into male gametes by clone Dd2 is likely to be a reason for the cytoplasmic inheritance pattern seen in the HB3 x Dd2 cross. However, incompetence of male or female gametes is unlikely to explain the uniparental dominance in recombinant progeny of the HB3 x 3D7 cross, since both parents readily self-fertilized and completed the malaria life cycle on their own. Instead, the data suggest unidirectional parental incompatibility in cross-fertilization of these malarial parasites, where a usually cosexual parental clone can participate only as a male or as a female. Such an incompatibility may be speculated as indicating an early phase of reproductive isolation of P. falciparum clones from different geographical regions.
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Affiliation(s)
- A B Vaidya
- Department of Microbiology and Immunology, Hahnemann University, Philadelphia, Pennsylvania 19102
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Hoffman SL, Oster CN, Plowe CV, Woollett GR, Beier JC, Chulay JD, Wirtz RA, Hollingdale MR, Mugambi M. Naturally acquired antibodies to sporozoites do not prevent malaria: vaccine development implications. Science 1987; 237:639-42. [PMID: 3299709 DOI: 10.1126/science.3299709] [Citation(s) in RCA: 157] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The first human vaccines against the malaria parasite have been designed to elicit antibodies to the circumsporozoite protein of Plasmodium falciparum. However, it is not known whether any level of naturally acquired antibodies to the circumsporozoite protein can predict resistance to Plasmodium falciparum malaria. In this study, 83 adults in a malaria-endemic region of Kenya were tested for circumsporozoite antibodies and then treated for malaria. They were monitored for the development of new malaria infections for 98 days. Antibody levels, as determined by four assays in vitro, were indistinguishable between the 60 individuals who did and the 23 who did not develop parasitemia during follow-up, and there was no apparent relation between day of onset of parasitemia and level of antibodies to circumsporozoite protein. Unless immunization with sporozoite vaccines induces antibodies that are quantitatively or qualitatively superior to the circumsporozoite antibodies in these adults, it is unlikely that such antibodies will prevent infection in areas with as intense malaria transmission as western Kenya.
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