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Tavul L, Hetzel MW, Teliki A, Walsh D, Kiniboro B, Rare L, Pulford J, Siba PM, Karl S, Makita L, Robinson L, Kattenberg JH, Laman M, Oswyn G, Mueller I. Efficacy of artemether-lumefantrine and dihydroartemisinin-piperaquine for the treatment of uncomplicated malaria in Papua New Guinea. Malar J 2018; 17:350. [PMID: 30290825 PMCID: PMC6173938 DOI: 10.1186/s12936-018-2494-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 09/27/2018] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND In 2009, the Papua New Guinea (PNG) Department of Health adopted artemether-lumefantrine (AL) and dihydroartemisinin-piperaquine (DHA-PPQ) as the first- and second-line treatments for uncomplicated malaria, respectively. This study was conducted to assess the efficacy of both drugs following adoption of the new policy. METHODS Between June 2012 and September 2014, a therapeutic efficacy study was conducted in East Sepik and Milne Bay Provinces of PNG in accordance with the standard World Health Organization (WHO) protocol for surveillance of anti-malarial drug efficacy. Patients ≥ 6 months of age with microscopy confirmed Plasmodium falciparum or Plasmodium vivax mono-infections were enrolled, treated with AL or DHA-PPQ, and followed up for 42 days. Study endpoints were adequate clinical and parasitological response (ACPR) on days 28 and 42. The in vitro efficacy of anti-malarials and the prevalence of selected molecular markers of resistance were also determined. RESULTS A total of 274 P. falciparum and 70 P. vivax cases were enrolled. The day-42 PCR-corrected ACPR for P. falciparum was 98.1% (104/106) for AL and 100% (135/135) for DHA-PPQ. The day-42 PCR-corrected ACPR for P. vivax was 79.0% (15/19) for AL and 92.3% (36/39) for DHA-PPQ. Day 3 parasite clearance of P. falciparum was 99.2% with AL and 100% with DHA-PPQ. In vitro testing of 96 samples revealed low susceptibility to chloroquine (34% of samples above IC50 threshold) but not to lumefantrine (0%). Molecular markers assessed in a sub-set of the study population indicated high rates of chloroquine resistance in P. falciparum (pfcrt SVMNT: 94.2%, n = 104) and in P. vivax (pvmdr1 Y976F: 64.8%, n = 54). CONCLUSIONS AL and DHA-PPQ were efficacious as first- and second-line treatments for uncomplicated malaria in PNG. Continued in vivo efficacy monitoring is warranted considering the threat of resistance to artemisinin and partner drugs in the region and scale-up of artemisinin-based combination therapy in PNG.
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Affiliation(s)
- Livingstone Tavul
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea.
| | - Manuel W Hetzel
- Swiss Tropical and Public Health Institute, PO Box, 4002, Basel, Switzerland.,University of Basel, Petersplatz 1, 4003, Basel, Switzerland
| | - Albina Teliki
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Dorish Walsh
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Benson Kiniboro
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Lawrence Rare
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Justin Pulford
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea.,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L35QA, UK
| | - Peter M Siba
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Stephan Karl
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea.,Infection and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Leo Makita
- National Department of Health, PO Box 807, Waigani, NCD, Papua New Guinea
| | - Leanne Robinson
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea.,Infection and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Johanna H Kattenberg
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea.,Institute of Tropical Medicine in Antwerp, Kronenburgstraat 43, 2000, Antwerp, Belgium
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, PO Box 378, Madang, Papua New Guinea
| | - Gilchrist Oswyn
- Milne Bay Provincial Health Authority, Lock Bag 402, Alotau, Papua New Guinea
| | - Ivo Mueller
- Infection and Immunity Division, Walter and Eliza Hall Institute, Melbourne, Australia.,Department of Medical Biology, University of Melbourne, Melbourne, Australia.,Institut Pasteur, 25-28, rue du Docteur-Roux, Cedex 15, 75724, Paris, France
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2
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Barnadas C, Timinao L, Javati S, Iga J, Malau E, Koepfli C, Robinson LJ, Senn N, Kiniboro B, Rare L, Reeder JC, Siba PM, Zimmerman PA, Karunajeewa H, Davis TM, Mueller I. Significant geographical differences in prevalence of mutations associated with Plasmodium falciparum and Plasmodium vivax drug resistance in two regions from Papua New Guinea. Malar J 2015; 14:399. [PMID: 26452541 PMCID: PMC4600278 DOI: 10.1186/s12936-015-0879-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 08/31/2015] [Indexed: 12/22/2022] Open
Abstract
Background Drug resistance remains a major obstacle to malaria treatment and control. It can arise and spread rapidly, and vary substantially even at sub-national level. National malaria programmes require cost-effective and timely ways of characterizing drug-resistance at multiple sites within their countries. Methods An improved multiplexed post-PCR ligase detection reaction—fluorescent microsphere assay (LDR-FMA) was used to simultaneously determine the presence of mutations in chloroquine resistance transporter (crt), multidrug resistance 1 (mdr1), dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes in Plasmodium falciparum (n = 727) and Plasmodium vivax (n = 574) isolates collected in 2006 from cross-sectional community population surveys in two geographically distinct regions (Madang and East Sepik) of Papua New Guinea (PNG) where strong regional differences in in vivo aminoquinoline and antifolate therapeutic efficacy had previously been observed. Data were compared to those of a follow-up survey conducted in 2010. Results Despite some very low parasite densities, the assay successfully amplified all P. falciparum and P. vivax loci in 77 and 69 % of samples, respectively. In 2006, prevalences of pfdhfr (59R-108 N) double mutation/wild type pfdhps haplotype, pfcrt SVMNT haplotype (72S-76T double mutation), and 86Y pfmdr1 mutation all exceeded 90 %. For P. vivax, 65 % carried at least two pvdhfr mutations, 97 % the 647P pvdhps mutation and 54 % the 976F pvmdr1 mutation. Prevalence of mutant haplotypes was higher in Madang than East Sepik for pfcrt SVMNT (97.4 vs 83.3 %, p = 0.001), pfdhfr (59R-108 N) (100 vs 90.6 %, p = 0.001), pvdhfr haplotypes (75.8 vs 47.6 %, p = 0.001) and pvmdr1 976F (71.2 vs 26.2 %, p < 0.001). Data from a subsequent Madang survey in 2010 showed that the prevalence of pfdhps mutations increased significantly from <5 % to >30 % (p < 0.001) as did the prevalence of pvdhfr mutant haplotypes (from 75.8 to 97.4 %, p = 0.012). Conclusions This LDR-FMA multiplex platform shows feasibility for low-cost, high-throughput, rapid characterization of a broad range of drug-resistance markers in low parasitaemia infections. Significant geographical differences in mutation prevalence correlate with previous genotyping surveys and in vivo trials and may reflect variable drug pressure and differences in health-care access in these two PNG populations. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0879-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Céline Barnadas
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea. .,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Lincoln Timinao
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | - Sarah Javati
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | - Jonah Iga
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | - Elisheba Malau
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Cristian Koepfli
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Leanne J Robinson
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea. .,Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Nicolas Senn
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea. .,Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | - Benson Kiniboro
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | - Lawrence Rare
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | | | - Peter M Siba
- Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea.
| | - Peter A Zimmerman
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, USA.
| | - Harin Karunajeewa
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
| | - Timothy M Davis
- School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.
| | - Ivo Mueller
- Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia. .,Centre de Recerca en Salut Internacional de Barcelona, Barcelona, Spain.
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Dogovski C, Xie SC, Burgio G, Bridgford J, Mok S, McCaw JM, Chotivanich K, Kenny S, Gnädig N, Straimer J, Bozdech Z, Fidock DA, Simpson JA, Dondorp AM, Foote S, Klonis N, Tilley L. Targeting the cell stress response of Plasmodium falciparum to overcome artemisinin resistance. PLoS Biol 2015; 13:e1002132. [PMID: 25901609 PMCID: PMC4406523 DOI: 10.1371/journal.pbio.1002132] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 03/16/2015] [Indexed: 11/30/2022] Open
Abstract
Successful control of falciparum malaria depends greatly on treatment with artemisinin combination therapies. Thus, reports that resistance to artemisinins (ARTs) has emerged, and that the prevalence of this resistance is increasing, are alarming. ART resistance has recently been linked to mutations in the K13 propeller protein. We undertook a detailed kinetic analysis of the drug responses of K13 wild-type and mutant isolates of Plasmodium falciparum sourced from a region in Cambodia (Pailin). We demonstrate that ART treatment induces growth retardation and an accumulation of ubiquitinated proteins, indicative of a cellular stress response that engages the ubiquitin/proteasome system. We show that resistant parasites exhibit lower levels of ubiquitinated proteins and delayed onset of cell death, indicating an enhanced cell stress response. We found that the stress response can be targeted by inhibiting the proteasome. Accordingly, clinically used proteasome inhibitors strongly synergize ART activity against both sensitive and resistant parasites, including isogenic lines expressing mutant or wild-type K13. Synergy is also observed against Plasmodium berghei in vivo. We developed a detailed model of parasite responses that enables us to infer, for the first time, in vivo parasite clearance profiles from in vitro assessments of ART sensitivity. We provide evidence that the clinical marker of resistance (delayed parasite clearance) is an indirect measure of drug efficacy because of the persistence of unviable parasites with unchanged morphology in the circulation, and we suggest alternative approaches for the direct measurement of viability. Our model predicts that extending current three-day ART treatment courses to four days, or splitting the doses, will efficiently clear resistant parasite infections. This work provides a rationale for improving the detection of ART resistance in the field and for treatment strategies that can be employed in areas with ART resistance. Resistance to artemisinin antimalarial drugs is jeopardizing malaria control. This study shows that proteasome-mediated stress responses can be targeted to overcome artemisinin resistance and suggests alternate therapeutic regimens and monitoring strategies. Resistance to artemisinin antimalarials, some of the most effective antimalarial drugs, has emerged in Southeast Asia, jeopardizing malaria control. We have undertaken a detailed study of artemisinin-sensitive and-resistant strains of Plasmodium falciparum, the parasite responsible for malaria, taken directly from the field in a region where resistance is developing. We compared these strains to lab strains engineered with either mutant or wild-type resistance alleles. We demonstrate that in sensitive P. falciparum, artemisinin induces growth retardation and accumulation of ubiquitinated proteins, indicating that the drugs activate the cellular stress response. Resistant parasites, on the other hand, exhibit reduced protein ubiquitination and delayed onset of cell death following drug exposure. We show that proteasome inhibitors strongly synergize artemisinin activity, offering a means of overcoming artemisinin resistance. We have developed a detailed model of parasite responses and have modelled in vivo clearance profiles. Our data indicate that extending artemisinin treatment from the standard three-day treatment to a four-day treatment will clear resistant parasites, thus preserving the use of this critical therapy in areas experiencing artemisinin resistance.
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Affiliation(s)
- Con Dogovski
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Stanley C Xie
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Gaetan Burgio
- John Curtin School of Medical Research, the Australian National University, Canberra, Australian Capital Territory, Australia; Australian School of Advanced Medicine, Macquarie University, Sydney, New South Wales, Australia
| | - Jess Bridgford
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Sachel Mok
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - James M McCaw
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia; Murdoch Childrens Research Institute, Royal Childrens Hospital, Victoria, Australia
| | | | - Shannon Kenny
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Nina Gnädig
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
| | - Judith Straimer
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, Singapore
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America; Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York, United States of America
| | - Julie A Simpson
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia
| | - Arjen M Dondorp
- Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford, United Kingdom
| | - Simon Foote
- John Curtin School of Medical Research, the Australian National University, Canberra, Australian Capital Territory, Australia
| | - Nectarios Klonis
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Leann Tilley
- Department of Biochemistry and Molecular Biology and ARC Centre of Excellence for Coherent X-ray Science, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, Victoria, Australia
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Liu H, Yang HL, Tang LH, Li XL, Huang F, Wang JZ, Li CF, Wang HY, Nie RH, Guo XR, Lin YX, Li M, Wang J, Xu JW. In vivo monitoring of dihydroartemisinin-piperaquine sensitivity in Plasmodium falciparum along the China-Myanmar border of Yunnan Province, China from 2007 to 2013. Malar J 2015; 14:47. [PMID: 25652213 PMCID: PMC4333884 DOI: 10.1186/s12936-015-0584-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/25/2015] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Artemisinin-based combination therapy (ACT) is the recommended first-line treatment of falciparum malaria in all endemic countries. Artemisinin resistance in Plasmodium falciparum has been confirmed in the Greater Mekong subregion (GMS). Dihydroartemisinin-piperaquine (DAPQ) is the most commonly used ACT in China. To understand the DAPQ sensitivity of P. falciparum, DAPQ resistance was monitored in vivo along the China-Myanmar border from 2007 to 2013. METHODS Eligible patients with mono-infections of P. falciparum were recruited to this study after obtaining full informed consent. DAPQ tablets for different categories of kg body weight ranges were given once a day for three days. Patients were followed up for 42 days. Polymerase chain reaction (PCR) was conducted to distinguish between re-infection and recrudescence, to confirm the Plasmodium species. The data were entered and analysed by the Kaplan-Meier method. Treatment outcome was assessed according to the WHO recommended standards. RESULTS 243 patients were completed valid follow-up. The fever clearance time (FCT) and asexual parasite clearance times (APCT) were, respectively, 36.5 ± 10.9 and 43.5 ± 11.8 hours, and there was an increasing trend of both FCT (F = 268.41, P < 0.0001) and APCT (F = 88.6, P < 0.0001) from 2007 to 2013. Eight (3.3%, 95% confidence interval, 1.4-6.4%) patients present parasitaemia on day three after medication; however they were spontaneous cure on day four. 241 (99.2%; 95% CI, 97.1-99.9%) of the patients were adequate clinical and parasitological response (ACPR) and the proportions of ACPR had not changed significantly from 2007 to 2013 (X(2) = 2.81, P = 0.7288). CONCLUSION In terms of efficacy, DAPQ is still an effective treatment for falciparum malaria. DAPQ sensitivity in P. falciparum had not significantly changed along the China-Myanmar border of Yunnan Province, China. However more attentions should be given to becoming slower fever and parasite clearance.
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Affiliation(s)
- Hui Liu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Heng-lin Yang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Lin-hua Tang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Xing-liang Li
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Fang Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Jia-zhi Wang
- Tengchong County Center for Disease Control and Prevention, Tengchong, 679100, China.
| | - Chun-fu Li
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Heng-ye Wang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Ren-hua Nie
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Xiang-rui Guo
- Yangjiang County Center for Disease Control and Prevention, Yingjiang, 679300, China.
| | - Ying-xue Lin
- Yangjiang County Center for Disease Control and Prevention, Yingjiang, 679300, China.
| | - Mei Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, 200025, PR China.
| | - Jian Wang
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
| | - Jian-wei Xu
- Yunnan Institute of Parasitic Diseases, Yunnan Provincial Center of Malaria Research, Yunnan Provincial Collaborative Innovation Center for Public Health and Disease Prevention and Control, Yunnan Provincial Key Laboratory of Vector-borne Diseases Control and Research, Puer, 665000, China.
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Mideo N, Kennedy DA, Carlton JM, Bailey JA, Juliano JJ, Read AF. Ahead of the curve: next generation estimators of drug resistance in malaria infections. Trends Parasitol 2013; 29:321-8. [PMID: 23746748 PMCID: PMC3694767 DOI: 10.1016/j.pt.2013.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 12/16/2022]
Abstract
Drug resistance is a major obstacle to controlling infectious diseases. A key challenge is detecting the early signs of drug resistance when little is known about its genetic basis. Focusing on malaria parasites, we propose a way to do this. Newly developing or low level resistance at low frequency in patients can be detected through a phenotypic signature: individual parasite variants clearing more slowly following drug treatment. Harnessing the abundance and resolution of deep sequencing data, our 'selection differential' approach addresses some limitations of extant methods of resistance detection, should allow for the earliest detection of resistance in malaria or other multi-clone infections, and has the power to uncover the true scale of the drug resistance problem.
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Affiliation(s)
- Nicole Mideo
- Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA.
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Detection of copy number variation and single nucleotide polymorphisms in genes involved in drug resistance and other phenotypic traits in P. falciparum clinical isolates collected from Uganda. Acta Trop 2013; 125:269-75. [PMID: 23220229 DOI: 10.1016/j.actatropica.2012.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 11/28/2012] [Accepted: 11/29/2012] [Indexed: 02/04/2023]
Abstract
There is an increasing interest in mapping the genes of pathogens which underlie important phenotypic traits such as virulence and drug resistance. The Plasmodium falciparum genome exhibits sequence variation that contributes to the pathogenic mechanisms of the parasite. Determining the prevalence of resistance markers could provide a prediction about drug efficacy. Copy number polymorphism (CNP) of genes has been shown to influence important parasite phenotypes. In this work, CNPs within genes involved in drug resistance and other phenotypic traits namely P. falciparum multidrug resistance 1 (pfmdr-1), GTP cyclo hydrolase (gch1), Ring infected erythrocyte surface antigen precursor (resa) and a hypothetical protein coding gene were analyzed by quantitative real time-polymerase reaction (qRT-PCR) among clinical isolates collected from Uganda. The pfmdr-1 codons 86 and 1246 and P. falciparum chloroquine resistance (pfcrt) codon 76 were genotyped for single nucleotide polymorphisms (SNPs) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and the proportion of resistance associated mutations were determined among mild and severe malaria cases using the chi-square test. Forty and 42 P. falciparum isolates collected from children with mild and severe malaria respectively were analyzed for CNPs. Seventy five and 81 P. falciparum isolates from children with mild or severe malaria were analyzed for SNPs. No pfmdr-1, gch1 or novel gene amplifications were identified among the P. falciparum clinical isolates. Although chloroquine was officially withdrawn from policy use since 7 years, all P. falciparum isolates presented the associated pfcrt K76T mutation, whatever the clinical status and no specific mutation in the pfmdr-1 gene was associated with disease type. In conclusion, this study provides baseline measures for continued surveillance for changes in copy number and SNP types among genes implicated in drug resistance and other important phenotypes that may have a potential role in parasite virulence mechanisms or drug treatment outcomes.
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Ng CL, Fidock DA. No evidence of decreased artemisinin efficacy in a high-transmission malaria setting in Mali. Am J Trop Med Hyg 2012; 87:16-17. [PMID: 22764285 PMCID: PMC3391042 DOI: 10.4269/ajtmh.2012.12-0344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
| | - David A. Fidock
- *Address correspondence to David A. Fidock, Department of Microbiology and Immunology, Columbia University Medical Center, 701 West 168th Street, Hammer HSC Room 1502, New York, NY 10032. E-mail:
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Rueangweerayut R, Phyo AP, Uthaisin C, Poravuth Y, Binh TQ, Tinto H, Pénali LK, Valecha N, Tien NT, Abdulla S, Borghini-Fuhrer I, Duparc S, Shin CS, Fleckenstein L. Pyronaridine-artesunate versus mefloquine plus artesunate for malaria. N Engl J Med 2012; 366:1298-309. [PMID: 22475593 DOI: 10.1056/nejmoa1007125] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Pyronaridine-artesunate is an artemisinin-based combination therapy under evaluation for the treatment of Plasmodium falciparum and P. vivax malaria. METHODS We conducted a phase 3, open-label, multicenter, noninferiority trial that included 1271 patients between 3 and 60 years of age from Asia (81.3%) or Africa (18.7%) with microscopically confirmed, uncomplicated P. falciparum malaria. Patients underwent randomization for treatment with a fixed-dose combination of 180 mg of pyronaridine and 60 mg of artesunate or with 250 mg of mefloquine plus 100 mg of artesunate. Doses were calculated according to body weight and administered once daily for 3 days. RESULTS Pyronaridine-artesunate was noninferior to mefloquine plus artesunate for the primary outcome: adequate clinical and parasitologic response in the per-protocol population on day 28, corrected for reinfection with the use of polymerase-chain-reaction (PCR) genotyping. For this outcome, efficacy in the group receiving pyronaridine-artesunate was 99.2% (743 of 749 patients; 95% confidence interval [CI], 98.3 to 99.7) and that in the group receiving mefloquine plus artesunate was 97.8% (360 of 368 patients; 95% CI, 95.8 to 99.1), with a treatment difference of 1.4 percentage points (95% CI, 0.0 to 3.5; P=0.05). In the intention-to-treat population, efficacy on day 42 in the group receiving pyronaridine-artesunate was 83.1% (705 of 848 patients; 95% CI, 80.4 to 85.6) and that in the group receiving mefloquine plus artesunate was 83.9% (355 of 423 patients; 95% CI, 80.1 to 87.3). In Cambodia, where there were 211 study patients, the median parasite clearance time was prolonged for both treatments: 64 hours versus 16.0 to 38.9 hours in other countries (P<0.001, on the basis of Kaplan-Meier estimates). Kaplan-Meier estimates of the recrudescence rate in the intention-to-treat population in Cambodia until day 42 were higher with pyronaridine-artesunate than with mefloquine plus artesunate (10.2% [95% CI, 5.4 to 18.6] vs. 0%; P=0.04 as calculated with the log-rank test), but similar for the other countries combined (4.7% [95% CI, 3.3 to 6.7] and 2.8% [95% CI, 1.5 to 5.3], respectively; P=0.24). Elevated levels of aminotransferases were observed in those receiving pyronaridine-artesunate. Two patients receiving mefloquine plus artesunate had seizures. CONCLUSIONS Fixed-dose pyronaridine-artesunate was efficacious in the treatment of uncomplicated P. falciparum malaria. In Cambodia, extended parasite clearance times were suggestive of in vivo resistance to artemisinin. (Funded by Shin Poong Pharmaceutical Company and the Medicines for Malaria Venture; ClinicalTrials.gov number, NCT00403260.).
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Pešić D, Starčević K, Toplak A, Herreros E, Vidal J, Almela MJ, Jelić D, Alihodžić S, Spaventi R, Perić M. Design, Synthesis, and in Vitro Activity of Novel 2′-O-Substituted 15-Membered Azalides. J Med Chem 2012; 55:3216-27. [DOI: 10.1021/jm201676t] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dijana Pešić
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Kristina Starčević
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Ana Toplak
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Esperanza Herreros
- Tres Cantos Medicines Development
Campus, Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos (Madrid), Spain
| | - Jaume Vidal
- Tres Cantos Medicines Development
Campus, Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos (Madrid), Spain
| | - Maria Jesus Almela
- Tres Cantos Medicines Development
Campus, Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, 28760 Tres Cantos (Madrid), Spain
| | - Dubravko Jelić
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Sulejman Alihodžić
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Radan Spaventi
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
| | - Mihaela Perić
- GlaxoSmithKline Research Centre Zagreb Ltd., Prilaz baruna Filipovića
29, 10000 Zagreb, Croatia
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Ashley EA, Lubell Y, White NJ, Turner P. Antimicrobial susceptibility of bacterial isolates from community acquired infections in Sub-Saharan Africa and Asian low and middle income countries. Trop Med Int Health 2011; 16:1167-79. [PMID: 21707879 PMCID: PMC3469739 DOI: 10.1111/j.1365-3156.2011.02822.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE Antimicrobial resistance has arisen across the globe in both nosocomial and community settings as a consequence of widespread antibiotic consumption. Poor availability of laboratory diagnosis means that resistance frequently goes unrecognised and may only be detected as clinical treatment failure. In this review, we provide an overview of the reported susceptibility of common community acquired bacterial pathogens in Sub-Saharan Africa and Asia to the antibiotics that are most widely used in these areas. METHODS We reviewed the literature for reports of the susceptibility of prevalent pathogens in the community in SSA and Asia to a range of commonly prescribed antibiotics. Inclusion criteria required that isolates were collected since 2004 and that they were obtained from either normally sterile sites or urine. The data were aggregated by region and by age group. RESULTS Eighty-three studies were identified since 2004 which reported the antimicrobial susceptibilities of common bacterial pathogens. Different methods were used to assess in-vitro susceptibility in the different studies. The quality of testing (evidenced by resistance profiles) also varied considerably. For Streptococcus pneumoniae and Neisseria meningitidis most drugs maintained relatively high efficacy, apart from co-trimoxazole to which there were high levels of resistance in most of the pathogens surveyed. CONCLUSIONS Compared with the enormous infectious disease burden and widespread use of antibiotics there are relatively few reliable data on antimicrobial susceptibility from tropical Asia and Africa upon which to draw firm conclusions, although it is evident that many commonly used antibiotics face considerable resistance in prevalent bacterial pathogens. This is likely to exacerbate morbidity and mortality. Investment in improved antimicrobial susceptibility testing and surveillance systems is likely to be a highly cost-effective strategy and should be complemented by centralized and readily accessible information resources.
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Affiliation(s)
- Elizabeth A Ashley
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol UniversityBangkok, Thailand
- Imperial College NHS TrustLondon, UK
| | - Yoel Lubell
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol UniversityBangkok, Thailand
- Centre for Tropical Medicine, University of OxfordOxford, UK
| | - Nicholas J White
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol UniversityBangkok, Thailand
- Centre for Tropical Medicine, University of OxfordOxford, UK
| | - Paul Turner
- Mahidol-Oxford Tropical Medicine Research Unit, Mahidol UniversityBangkok, Thailand
- Centre for Tropical Medicine, University of OxfordOxford, UK
- Shoklo Malaria Research UnitMae Sot, Thailand
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11
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Lye DCB, Kwa ALH, Chlebicki P. World Health Day 2011: Antimicrobial Resistance and Practical Solutions. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2011. [DOI: 10.47102/annals-acadmedsg.v40n4p156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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12
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Lang T. Advancing Global Health Research Through Digital Technology and Sharing Data. Science 2011; 331:714-7. [DOI: 10.1126/science.1199349] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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13
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Chen DS, Barry AE, Leliwa-Sytek A, Smith TA, Peterson I, Brown SM, Migot-Nabias F, Deloron P, Kortok MM, Marsh K, Daily JP, Ndiaye D, Sarr O, Mboup S, Day KP. A molecular epidemiological study of var gene diversity to characterize the reservoir of Plasmodium falciparum in humans in Africa. PLoS One 2011; 6:e16629. [PMID: 21347415 PMCID: PMC3036650 DOI: 10.1371/journal.pone.0016629] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 01/06/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The reservoir of Plasmodium infection in humans has traditionally been defined by blood slide positivity. This study was designed to characterize the local reservoir of infection in relation to the diverse var genes that encode the major surface antigen of Plasmodium falciparum blood stages and underlie the parasite's ability to establish chronic infection and transmit from human to mosquito. METHODOLOGY/PRINCIPAL FINDINGS We investigated the molecular epidemiology of the var multigene family at local sites in Gabon, Senegal and Kenya which differ in parasite prevalence and transmission intensity. 1839 distinct var gene types were defined by sequencing DBLα domains in the three sites. Only 76 (4.1%) var types were found in more than one population indicating spatial heterogeneity in var types across the African continent. The majority of var types appeared only once in the population sample. Non-parametric statistical estimators predict in each population at minimum five to seven thousand distinct var types. Similar diversity of var types was seen in sites with different parasite prevalences. CONCLUSIONS/SIGNIFICANCE Var population genomics provides new insights into the epidemiology of P. falciparum in Africa where malaria has never been conquered. In particular, we have described the extensive reservoir of infection in local African sites and discovered a unique var population structure that can facilitate superinfection through minimal overlap in var repertoires among parasite genomes. Our findings show that var typing as a molecular surveillance system defines the extent of genetic complexity in the reservoir of infection to complement measures of malaria prevalence. The observed small scale spatial diversity of var genes suggests that var genetics could greatly inform current malaria mapping approaches and predict complex malaria population dynamics due to the import of var types to areas where no widespread pre-existing immunity in the population exists.
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Affiliation(s)
- Donald S. Chen
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Department of Medicine, New York University School of Medicine, New York, New York, United States of America
| | - Alyssa E. Barry
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
- Centre for Population Health, Burnet Institute, Melbourne, Australia
- Department of Medicine, Central and Eastern Clinical School, Monash University, Victoria, Australia
| | - Aleksandra Leliwa-Sytek
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Terry-Ann Smith
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Ingrid Peterson
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Stuart M. Brown
- Center for Health Informatics and Bioinformatics, New York University School of Medicine, New York, New York, United States of America
| | - Florence Migot-Nabias
- Institut de Recherche pour le Développement, Faculté de Pharmacie, Université Paris 5, Paris, France
| | - Philippe Deloron
- Institut de Recherche pour le Développement, Faculté de Pharmacie, Université Paris 5, Paris, France
| | - Moses M. Kortok
- Kenya Medical Research Institute, Centre for Geographic Medicine Research, Kilifi, Kenya
| | - Kevin Marsh
- Kenya Medical Research Institute, Centre for Geographic Medicine Research, Kilifi, Kenya
| | - Johanna P. Daily
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Daouda Ndiaye
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Ousmane Sarr
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Souleymane Mboup
- Faculty of Medicine and Pharmacy, Cheikh Anta Diop University, Dakar, Senegal
| | - Karen P. Day
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
- Peter Medawar Building for Pathogen Research and Department of Zoology, University of Oxford, Oxford, United Kingdom
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Hedt BL, Laufer MK, Cohen T. Drug resistance surveillance in resource-poor settings: current methods and considerations for TB, HIV, and malaria. Am J Trop Med Hyg 2011; 84:192-9. [PMID: 21292884 PMCID: PMC3029167 DOI: 10.4269/ajtmh.2011.10-0363] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 10/26/2010] [Indexed: 11/07/2022] Open
Abstract
In resource-constrained environments, monitoring the occurrence of tuberculosis (TB), human immunodeficiency virus (HIV), or malaria resistant to the limited number of available drugs is essential for national treatment program success. Countries with limited resources and technical capacity rely on survey designs and methods that are simple and easily integrated into routine clinical activities to minimize the impact on overburdened clinics. This paper reviews the most commonly used methods for drug-resistance surveillance of TB, HIV, and malaria and discusses the strengths and limitations of these different strategies.
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Affiliation(s)
- Bethany L Hedt
- Department of Biostatistics, Harvard School of Public Health, Boston, MA 02115, USA.
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15
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Bibliography. Genetics. Current world literature. Curr Opin Pediatr 2010; 22:833-5. [PMID: 21610333 DOI: 10.1097/mop.0b013e32834179f9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Derrer B, Windeisen V, Guédez Rodríguez G, Seidler J, Gengenbacher M, Lehmann WD, Rippe K, Sinning I, Tews I, Kappes B. Defining the structural requirements for ribose 5-phosphate-binding and intersubunit cross-talk of the malarial pyridoxal 5-phosphate synthase. FEBS Lett 2010; 584:4169-74. [PMID: 20837012 DOI: 10.1016/j.febslet.2010.09.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 07/23/2010] [Accepted: 09/02/2010] [Indexed: 11/28/2022]
Abstract
Most organisms synthesise the B(6) vitamer pyridoxal 5-phosphate (PLP) via the glutamine amidotransferase PLP synthase, a large enzyme complex of 12 Pdx1 synthase subunits with up to 12 Pdx2 glutaminase subunits attached. Deletion analysis revealed that the C-terminus has four distinct functionalities: assembly of the Pdx1 monomers, binding of the pentose substrate (ribose 5-phosphate), formation of the reaction intermediate I(320), and finally PLP synthesis. Deletions of distinct C-terminal regions distinguish between these individual functions. PLP formation is the only function that is conferred to the enzyme by the C-terminus acting in trans, explaining the cooperative nature of the complex.
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Affiliation(s)
- Bianca Derrer
- University Hospital Heidelberg, Department of Infectious Diseases, Parasitology, Heidelberg, Germany
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Nain V, Sahi S, Verma A. CPP-ZFN: a potential DNA-targeting anti-malarial drug. Malar J 2010; 9:258. [PMID: 20846404 PMCID: PMC2949742 DOI: 10.1186/1475-2875-9-258] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 09/16/2010] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Multidrug-resistant Plasmodium is of major concern today. Effective vaccines or successful applications of RNAi-based strategies for the treatment of malaria are currently unavailable. An unexplored area in the field of malaria research is the development of DNA-targeting drugs that can specifically interact with parasitic DNA and introduce deleterious changes, leading to loss of vital genome function and parasite death. PRESENTATION OF THE HYPOTHESIS Advances in the development of zinc finger nuclease (ZFN) with engineered DNA recognition domains allow us to design and develop nuclease of high target sequence specificity with a mega recognition site that typically occurs only once in the genome. Moreover, cell-penetrating peptides (CPP) can cross the cell plasma membrane and deliver conjugated protein, nucleic acid, or any other cargo to the cytoplasm, nucleus, or mitochondria. This article proposes that a drug from the combination of the CPP and ZFN systems can effectively enter the intracellular parasite, introduce deleterious changes in its genome, and eliminate the parasite from the infected cells. TESTING THE HYPOTHESIS Availability of a DNA-binding motif for more than 45 triplets and its modular nature, with freedom to change number of fingers in a ZFN, makes development of customized ZFN against diverse target DNA sequence of any gene feasible. Since the Plasmodium genome is highly AT rich, there is considerable sequence site diversity even for the structurally and functionally conserved enzymes between Plasmodium and humans. CPP can be used to deliver ZFN to the intracellular nucleus of the parasite. Signal-peptide-based heterologous protein translocation to Plasmodium-infected RBCs (iRBCs) and different Plasmodium organelles have been achieved. With successful fusion of CPP with mitochondrial- and nuclear-targeting peptides, fusion of CPP with 1 more Plasmodium cell membrane translocation peptide seems achievable. IMPLICATIONS OF THE HYPOTHESIS Targeting of the Plasmodium genome using ZFN has great potential for the development of anti-malarial drugs. It allows the development of a single drug against all malarial infections, including multidrug-resistant strains. Availability of multiple ZFN target sites in a single gene will provide alternative drug target sites to combat the development of resistance in the future.
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Affiliation(s)
- Vikrant Nain
- School of Biotechnology, Gautam Buddha University, Greater Noida-201308, India
| | - Shakti Sahi
- School of Biotechnology, Gautam Buddha University, Greater Noida-201308, India
| | - Anju Verma
- School of Biological Sciences, University of Missouri, Kansas City, MO- 64110, USA
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Monitoring antimalarial resistance: launching a cooperative effort. Trends Parasitol 2010; 26:221-4. [DOI: 10.1016/j.pt.2010.02.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 02/12/2010] [Accepted: 02/17/2010] [Indexed: 11/18/2022]
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Kafsack BF, Llinás M. Eating at the table of another: metabolomics of host-parasite interactions. Cell Host Microbe 2010; 7:90-9. [PMID: 20159614 PMCID: PMC2825149 DOI: 10.1016/j.chom.2010.01.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 01/27/2010] [Accepted: 01/28/2010] [Indexed: 01/07/2023]
Abstract
The application of metabolomics, the global analysis of metabolite levels, to the study of protozoan parasites has become an important tool for understanding the host-parasite relationship and holds promise for the development of direly needed therapeutics and improved diagnostics. Research advances over the past decade have opened the door for a systems biology approach to protozoan parasites with metabolomics, providing a crucial readout of metabolic activity. In this review, we highlight recent metabolomic approaches to protozoan parasites, including metabolite profiling, integration with genomics, transcription, and proteomic analysis, and the use of metabolic fingerprints for the diagnosis of parasitic infections.
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Affiliation(s)
- Björn F.C. Kafsack
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Manuel Llinás
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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Chaijaroenkul W, Wisedpanichkij R, Na-Bangchang K. Monitoring of in vitro susceptibilities and molecular markers of resistance of Plasmodium falciparum isolates from Thai-Myanmar border to chloroquine, quinine, mefloquine and artesunate. Acta Trop 2010; 113:190-4. [PMID: 19879850 DOI: 10.1016/j.actatropica.2009.10.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 10/22/2009] [Accepted: 10/22/2009] [Indexed: 11/15/2022]
Abstract
Malaria is one of the major causes of morbidity and mortality worldwide. The major factor which has aggravated the situation is the emergence of multidrug resistant Plasmodium falciparum malaria. To successfully deal with the problem, thorough understanding of the molecular bases for reduced parasite sensitivity to existing antimalarial drugs is of considerable importance. The objective of this work was to broaden the insight into the molecular mechanisms of resistance of P. falciparum to quinoline-containing antimalarials and artemisinin derivatives. Polymorphisms of the candidate genes pfmdr1 and pfcrt were investigated in relation to the susceptibility (in vitro sensitivity) of P. falciparum isolates to chloroquine (CQ), mefloquine (MQ), quinine (QN) and the artemisinin derivative - artesunate (AS). A total of 26 P. falciparum isolates were successful cultured. In vitro sensitivity results indicate the increase in susceptibility of P. falciparum strains in Thailand to CQ, while the susceptibility to MQ and QN was markedly declined. The pattern of cross-resistance was observed between MQ vs QN vs AS. Only one point mutation in the pfmdr1 gene, i.e., N86Y was observed with low prevalence of 7.7% (2/26). In contrast, the mutations at positions 76T, 220S, 271E, 326S, 356T and 371I in the pfcrt gene were identified in almost all isolates (25 isolates, 96.2%). The association between polymorphisms of the pfmdr1 and susceptibility of the parasite to MQ and QN was observed (increased susceptibilities to MQ and QN in isolates with mutations). Moreover, the correlation between pfmdr1 gene amplification and susceptibility of the parasite to MQ, QN and AS was observed (decreased susceptibilities to MQ, QN and AS in isolates with increased pfmdr1 copy number).
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Affiliation(s)
- Wanna Chaijaroenkul
- Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Rangsit, Patumthani 12121, Thailand
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