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Fornace KM, Zorello Laporta G, Vythilingham I, Chua TH, Ahmed K, Jeyaprakasam NK, de Castro Duarte AMR, Amir A, Phang WK, Drakeley C, Sallum MAM, Lau YL. Simian malaria: a narrative review on emergence, epidemiology and threat to global malaria elimination. THE LANCET. INFECTIOUS DISEASES 2023; 23:e520-e532. [PMID: 37454671 DOI: 10.1016/s1473-3099(23)00298-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/19/2023] [Accepted: 04/28/2023] [Indexed: 07/18/2023]
Abstract
Simian malaria from wild non-human primate populations is increasingly recognised as a public health threat and is now the main cause of human malaria in Malaysia and some regions of Brazil. In 2022, Malaysia became the first country not to achieve malaria elimination due to zoonotic simian malaria. We review the global distribution and drivers of simian malaria and identify priorities for diagnosis, treatment, surveillance, and control. Environmental change is driving closer interactions between humans and wildlife, with malaria parasites from non-human primates spilling over into human populations and human malaria parasites spilling back into wild non-human primate populations. These complex transmission cycles require new molecular and epidemiological approaches to track parasite spread. Current methods of malaria control are ineffective, with wildlife reservoirs and primarily outdoor-biting mosquito vectors urgently requiring the development of novel control strategies. Without these, simian malaria has the potential to undermine malaria elimination globally.
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Affiliation(s)
- Kimberly M Fornace
- School of Biodiversity, One Health and Veterinary Medicine, University of Glasgow, Glasgow, UK; Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore, Singapore; Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | - Gabriel Zorello Laporta
- Graduate Research and Innovation Program, Centro Universitario FMABC, Santo André, São Paulo, Brazil
| | | | | | - Kamruddin Ahmed
- Department of Pathology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia; Borneo Medical and Health Research Centre, Universiti Malaysia Sabah, Kota Kinabalu, Malaysia
| | - Nantha K Jeyaprakasam
- Biomedical Science Programme, Center for Toxicology and Health Risk Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Ana Maria Ribeiro de Castro Duarte
- Laboratory of Protozoology, Institute of Tropical Medicine of São Paulo, Universidade de São Paulo, São Paulo, Brazil; Instituto Pasteur, Secretaria de Estado da Saude de São Paulo, São Paulo, Brazil
| | - Amirah Amir
- Department of Parasitology, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Wei Kit Phang
- Department of Parasitology, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Chris Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Maria Anice M Sallum
- Departamento de Epidemiologia, Faculdade de Saude Publica, Universidade de São Paulo, São Paulo, Brazil
| | - Yee Ling Lau
- Department of Parasitology, Universiti Malaya, Kuala Lumpur, Malaysia
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Sangsri R, Choowongkomon K, Tuntipaiboontana R, Sugaram R, Boondej P, Sudathip P, Dondorp AM, Imwong M. Limited Polymorphism in the Dihydrofolate Reductase (dhfr) and dihydropteroate synthase genes (dhps) of Plasmodium knowlesi isolate from Thailand. Acta Trop 2023; 248:107016. [PMID: 37683820 PMCID: PMC10632683 DOI: 10.1016/j.actatropica.2023.107016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/27/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023]
Abstract
BACKGROUND The 2022 malaria WHO reported around 4000 P. knowlesi infections in the South-East Asia region. In the same period, 72 positive cases were reported by the Department of Disease Control in Thailand, suggesting a persistent infection. Little is known about dihydrofolate reductase (pkdhfr) and dihydropteroate synthase (pkdhps), putative antimalarial resistance markers for P. knowlesi. The relevant amplification and sequencing protocol are presently unavailable. In this study, we developed a protocol for amplifying and evaluating pkdhps mutations. The haplotype pattern of pkdhfr-pkdhps in Thai isolates was analyzed, and the effects of these pkdhps mutations were predicted by using a computer program. METHODS Pkdhps were amplified and sequenced from 28 P. knowlesi samples collected in 2008 and 2020 from nine provinces across Thailand. Combining pkdhfr sequencing data from previous work with pkdhps data to analyze polymorphisms of pkdhfr and pkdhps haplotype. Protein modeling and molecular docking were constructed using two inhibitors, sulfadoxine and sulfamethoxazole, and further details were obtained through analyses of protein-ligand interactions by using the Genetic Optimisation for Ligand Docking program. A phylogenetic tree cluster analysis was reconstructed to compare the P. knowlesi Malaysia isolates. RESULTS Five nonsynonymous mutations in the pkdhps were detected outside the equivalence of the binding pocket sites to sulfadoxine and sulfamethoxazole, which are at N391S, E421G, I425R, A449S, and N517S. Based on the modeling and molecular docking analyses, the N391S and N517S mutations located close to the enzyme-binding pocket demonstrated a different docking score and protein-ligand interaction in loop 2 of the enzyme. These findings indicated that it was less likely to induce drug resistance. Of the four haplotypes of pkdhfr-pkdhps, the most common one is the R34L pkdhfr mutation and the pkdhps quadruple mutation (GRSS) at E421G, I425R, A449S, and N517S, which were observed in P. knowlesi in southern Thailand (53.57%). Based on the results of neighbor-joining analysis for pkdhfr and pkdhps, the samples isolated from eastern Thailand displayed a close relationship with Cambodia isolates, while southern Thailand isolates showed a long branch separated from the Malaysian isolates. CONCLUSIONS A new PCR protocol amplification and evaluation of dihydropteroate synthase mutations in Knowlesi (pkdhps) has been developed. The most prevalent pkdhfr-pkdhps haplotypes (53.57%) in southern Thailand are R34L pkdhfr mutation and pkdhps quadruple mutation. Further investigation requires additional phenotypic data from clinical isolates, transgenic lines expressing mutant alleles, or recombinant proteins.
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Affiliation(s)
- Raweewan Sangsri
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Kiattawee Choowongkomon
- Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok 10903, Thailand
| | - Runch Tuntipaiboontana
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Rungniran Sugaram
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
| | - Patcharida Boondej
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
| | - Prayuth Sudathip
- Division of Vector Borne Diseases, Department of Disease Control, Ministry of Public Health, Nonthaburi 11000, Thailand
| | - Arjen M Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Mallika Imwong
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand.
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3
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Ahmed MA, Baruah P, Saif A, Han JH, Al-Zharani M, Wazid SW, Alkahtani S, Patgiri SJ, Al-Eissa MS, Quan FS. In Silico Analysis Reveals High Levels of Genetic Diversity of Plasmodium knowlesi Cell Traversal Protein for Ookinetes and Sporozoites ( PkCelTOS) in Clinical Samples. Trop Med Infect Dis 2023; 8:380. [PMID: 37624318 PMCID: PMC10458480 DOI: 10.3390/tropicalmed8080380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 07/05/2023] [Accepted: 07/20/2023] [Indexed: 08/26/2023] Open
Abstract
The cell-traversal protein for ookinetes and sporozoites (CelTOS), expressed on the surface of ookinetes and sporozoitesin Plasmodium species, is a promising malaria vaccine candidate. CelTOS is essential for parasite invasion into mosquito midgut and human hepatocytes, thereby contributing to malaria transmission and disease pathogenesis. This study explores the genetic diversity, polymorphisms, haplotypes, natural selection, phylogenetic analysis, and epitope prediction in the full-length Plasmodium knowlesi CelTOS gene in clinical samples from Sarawak, Malaysian Borneo, and long-term laboratory strains from Peninsular Malaysia and the Philippines. Our analysis revealed a high level of genetic variation in the PkCelTOS gene, with a nucleotide diversity of π ~ 0.021, which was skewed towards the 3' end of the gene. This level of diversity is double that observed in PfCelTOS and 20 times that observed in PvCelTOS from worldwide clinical samples. Tests of natural selection revealed evidence for positive selection within clinical samples. Phylogenetic analysis of the amino acid sequence of PkCelTOS revealed the presence of two distinct groups, although no geographical clustering was observed. Epitope prediction analysis identified two potential epitopes (96AQLKATA102 and 124TIKPPRIKED133) using the IEDB server and one epitope (125IKPPRIKED133) by Bcepred server on the C' terminal region of PkCelTOS protein. Both the servers predicted a common epitope region of nine amino acid length (IKPPRIKED) peptide, which can be studied in the future as a potential candidate for vaccine development. These findings shed light on the genetic diversity, polymorphism, haplotypes, and natural selection within PkCelTOS in clinical samples and provide insights about its future prospects as a potential candidate for P. knowlesi malaria vaccine development.
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Affiliation(s)
- Md Atique Ahmed
- ICMR-Regional Medical Research Centre, NE Region, Dibrugarh 786010, Assam, India (S.J.P.)
| | - Pratisthita Baruah
- ICMR-Regional Medical Research Centre, NE Region, Dibrugarh 786010, Assam, India (S.J.P.)
| | - Ahmed Saif
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, King Khalid University, Abha 61321, Saudi Arabia
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon 24341, Republic of Korea
| | - Mohammed Al-Zharani
- Biology Department, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSU), Riyadh 11623, Saudi Arabia (M.S.A.-E.)
| | - Syeda Wasfeea Wazid
- Arogyo Society of Health, Welfare and Support (ASHWAS), Guwahati 785640, Assam, India;
| | - Saad Alkahtani
- Department of Zoology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Saurav J. Patgiri
- ICMR-Regional Medical Research Centre, NE Region, Dibrugarh 786010, Assam, India (S.J.P.)
| | - Mohammed S. Al-Eissa
- Biology Department, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSU), Riyadh 11623, Saudi Arabia (M.S.A.-E.)
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
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Turkiewicz A, Manko E, Oresegun DR, Nolder D, Spadar A, Sutherland CJ, Cox-Singh J, Moon RW, Lau YL, Campino S, Clark TG. Population genetic analysis of Plasmodium knowlesi reveals differential selection and exchange events between Borneo and Peninsular sub-populations. Sci Rep 2023; 13:2142. [PMID: 36750737 PMCID: PMC9905552 DOI: 10.1038/s41598-023-29368-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
The zoonotic Plasmodium knowlesi parasite is a growing public health concern in Southeast Asia, especially in Malaysia, where elimination of P. falciparum and P. vivax malaria has been the focus of control efforts. Understanding of the genetic diversity of P. knowlesi parasites can provide insights into its evolution, population structure, diagnostics, transmission dynamics, and the emergence of drug resistance. Previous work has revealed that P. knowlesi fall into three main sub-populations distinguished by a combination of geographical location and macaque host (Macaca fascicularis and M. nemestrina). It has been shown that Malaysian Borneo groups display profound heterogeneity with long regions of high or low divergence resulting in mosaic patterns between sub-populations, with some evidence of chromosomal-segment exchanges. However, the genetic structure of non-Borneo sub-populations is less clear. By gathering one of the largest collections of P. knowlesi whole-genome sequencing data, we studied structural genomic changes across sub-populations, with the analysis revealing differences in Borneo clusters linked to mosquito-related stages of the parasite cycle, in contrast to differences in host-related stages for the Peninsular group. Our work identifies new genetic exchange events, including introgressions between Malaysian Peninsular and M. nemestrina-associated clusters on various chromosomes, including in parasite invasion genes (DBP[Formula: see text], NBPX[Formula: see text] and NBPX[Formula: see text]), and important proteins expressed in the vertebrate parasite stages. Recombination events appear to have occurred between the Peninsular and M. fascicularis-associated groups, including in the DBP[Formula: see text] and DBP[Formula: see text] invasion associated genes. Overall, our work finds that genetic exchange events have occurred among the recognised contemporary groups of P. knowlesi parasites during their evolutionary history, leading to apparent mosaicism between these sub-populations. These findings generate new hypotheses relevant to parasite evolutionary biology and P. knowlesi epidemiology, which can inform malaria control approaches to containing the impact of zoonotic malaria on human communities.
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Affiliation(s)
- Anna Turkiewicz
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Emilia Manko
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Damiola R Oresegun
- Division of Infection, School of Medicine, University of St Andrews, St Andrews, UK
| | - Debbie Nolder
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
- UK Health Security Agency Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Anton Spadar
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Colin J Sutherland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
- UK Health Security Agency Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Janet Cox-Singh
- Division of Infection, School of Medicine, University of St Andrews, St Andrews, UK
| | - Robert W Moon
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | | | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
| | - Taane G Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
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Spatio-temporal distribution and hotspots of Plasmodium knowlesi infections in Sarawak, Malaysian Borneo. Sci Rep 2022; 12:17284. [PMID: 36241678 PMCID: PMC9568661 DOI: 10.1038/s41598-022-21439-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 09/27/2022] [Indexed: 01/10/2023] Open
Abstract
Plasmodium knowlesi infections in Malaysia are a new threat to public health and to the national efforts on malaria elimination. In the Kapit division of Sarawak, Malaysian Borneo, two divergent P. knowlesi subpopulations (termed Cluster 1 and Cluster 2) infect humans and are associated with long-tailed macaque and pig-tailed macaque hosts, respectively. It has been suggested that forest-associated activities and environmental modifications trigger the increasing number of knowlesi malaria cases. Since there is a steady increase of P. knowlesi infections over the past decades in Sarawak, particularly in the Kapit division, we aimed to identify hotspots of knowlesi malaria cases and their association with forest activities at a geographical scale using the Geographic Information System (GIS) tool. A total of 1064 P. knowlesi infections from 2014 to 2019 in the Kapit and Song districts of the Kapit division were studied. Overall demographic data showed that males and those aged between 18 and 64 years old were the most frequently infected (64%), and 35% of infections involved farming activities. Thirty-nine percent of Cluster 1 infections were mainly related to farming surrounding residential areas while 40% of Cluster 2 infections were associated with activities in the deep forest. Average Nearest Neighbour (ANN) analysis showed that humans infected with both P. knowlesi subpopulations exhibited a clustering distribution pattern of infection. The Kernel Density Analysis (KDA) indicated that the hotspot of infections surrounding Kapit and Song towns were classified as high-risk areas for zoonotic malaria transmission. This study provides useful information for staff of the Sarawak State Vector-Borne Disease Control Programme in their efforts to control and prevent zoonotic malaria.
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Brashear AM, Cui L. Population genomics in neglected malaria parasites. Front Microbiol 2022; 13:984394. [PMID: 36160257 PMCID: PMC9493318 DOI: 10.3389/fmicb.2022.984394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Malaria elimination includes neglected human malaria parasites Plasmodium vivax, Plasmodium ovale spp., and Plasmodium malariae. Biological features such as association with low-density infection and the formation of hypnozoites responsible for relapse make their elimination challenging. Studies on these parasites rely primarily on clinical samples due to the lack of long-term culture techniques. With improved methods to enrich parasite DNA from clinical samples, whole-genome sequencing of the neglected malaria parasites has gained increasing popularity. Population genomics of more than 2200 P. vivax global isolates has improved our knowledge of parasite biology and host-parasite interactions, identified vaccine targets and potential drug resistance markers, and provided a new way to track parasite migration and introduction and monitor the evolutionary response of local populations to elimination efforts. Here, we review advances in population genomics for neglected malaria parasites, discuss how the rich genomic information is being used to understand parasite biology and epidemiology, and explore opportunities for the applications of malaria genomic data in malaria elimination practice.
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Oresegun DR, Thorpe P, Benavente ED, Campino S, Muh F, Moon RW, Clark TG, Cox-Singh J. De Novo Assembly of Plasmodium knowlesi Genomes From Clinical Samples Explains the Counterintuitive Intrachromosomal Organization of Variant SICAvar and kir Multiple Gene Family Members. Front Genet 2022; 13:855052. [PMID: 35677565 PMCID: PMC9169567 DOI: 10.3389/fgene.2022.855052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/15/2022] [Indexed: 12/31/2022] Open
Abstract
Plasmodium knowlesi, a malaria parasite of Old World macaque monkeys, is used extensively to model Plasmodium biology. Recently, P. knowlesi was found in the human population of Southeast Asia, particularly Malaysia. P. knowlesi causes uncomplicated to severe and fatal malaria in the human host with features in common with the more prevalent and virulent malaria caused by Plasmodium falciparum. As such, P. knowlesi presents a unique opportunity to develop experimental translational model systems for malaria pathophysiology informed by clinical data from same-species human infections. Experimental lines of P. knowlesi represent well-characterized genetically stable parasites, and to maximize their utility as a backdrop for understanding malaria pathophysiology, genetically diverse contemporary clinical isolates, essentially wild-type, require comparable characterization. The Oxford Nanopore PCR-free long-read sequencing platform was used to sequence and de novo assemble P. knowlesi genomes from frozen clinical samples. The sequencing platform and assembly pipelines were designed to facilitate capturing data and describing, for the first time, P. knowlesi schizont-infected cell agglutination (SICA) var and Knowlesi-Interspersed Repeats (kir) multiple gene families in parasites acquired from nature. The SICAvar gene family members code for antigenically variant proteins analogous to the virulence-associated P. falciparum erythrocyte membrane protein (PfEMP1) multiple var gene family. Evidence presented here suggests that the SICAvar family members have arisen through a process of gene duplication, selection pressure, and variation. Highly evolving genes including PfEMP1family members tend to be restricted to relatively unstable sub-telomeric regions that drive change with core genes protected in genetically stable intrachromosomal locations. The comparable SICAvar and kir gene family members are counter-intuitively located across chromosomes. Here, we demonstrate that, in contrast to conserved core genes, SICAvar and kir genes occupy otherwise gene-sparse chromosomal locations that accommodate rapid evolution and change. The novel methods presented here offer the malaria research community not only new tools to generate comprehensive genome sequence data from small clinical samples but also new insight into the complexity of clinically important real-world parasites.
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Affiliation(s)
- Damilola R. Oresegun
- Division of Infection and Global Health, School of Medicine, University of St Andrews, Scotland, United Kingdom
| | - Peter Thorpe
- Division of Infection and Global Health, School of Medicine, University of St Andrews, Scotland, United Kingdom
| | - Ernest Diez Benavente
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Fauzi Muh
- Division of Infection and Global Health, School of Medicine, University of St Andrews, Scotland, United Kingdom
| | - Robert William Moon
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Taane Gregory Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Janet Cox-Singh
- Division of Infection and Global Health, School of Medicine, University of St Andrews, Scotland, United Kingdom
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Lee WC, Cheong FW, Amir A, Lai MY, Tan JH, Phang WK, Shahari S, Lau YL. Plasmodium knowlesi: the game changer for malaria eradication. Malar J 2022; 21:140. [PMID: 35505339 PMCID: PMC9066973 DOI: 10.1186/s12936-022-04131-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 03/18/2022] [Indexed: 11/12/2022] Open
Abstract
Plasmodium knowlesi is a zoonotic malaria parasite that has gained increasing medical interest over the past two decades. This zoonotic parasitic infection is prevalent in Southeast Asia and causes many cases with fulminant pathology. Despite several biogeographical restrictions that limit its distribution, knowlesi malaria cases have been reported in different parts of the world due to travelling and tourism activities. Here, breakthroughs and key information generated from recent (over the past five years, but not limited to) studies conducted on P. knowlesi were reviewed, and the knowledge gap in various research aspects that need to be filled was discussed. Besides, challenges and strategies required to control and eradicate human malaria with this emerging and potentially fatal zoonosis were described.
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Affiliation(s)
- Wenn-Chyau Lee
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Fei Wen Cheong
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Amirah Amir
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Meng Yee Lai
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Jia Hui Tan
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Wei Kit Phang
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Shahhaziq Shahari
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Yee-Ling Lau
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia.
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Lempang MEP, Dewayanti FK, Syahrani L, Permana DH, Malaka R, Asih PBS, Syafruddin D. Primate malaria: An emerging challenge of zoonotic malaria in Indonesia. One Health 2022; 14:100389. [PMID: 35686151 PMCID: PMC9171520 DOI: 10.1016/j.onehlt.2022.100389] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/01/2022] [Accepted: 04/03/2022] [Indexed: 12/23/2022] Open
Abstract
The emergence of zoonotic malaria in different parts of the world, including Indonesia poses a challenge to the current malaria control and elimination program that target global malaria elimination at 2030. The reported cases in human include Plasmodium knowlesi, P. cynomolgi and P. inui, in South and Southeast Asian region and P. brazilianum and P. simium in Latin America. All are naturally found in the Old and New-world monkeys, macaques spp. This review focuses on the currently available data that may represent primate malaria as an emerging challenge of zoonotic malaria in Indonesia, the distribution of non-human primates and the malaria parasites it carries, changes in land use and deforestation that impact the habitat and intensifies interaction between the non-human primate and the human which facilitate spill-over of the pathogens. Although available data in Indonesia is very limited, a growing body of evidence indicate that the challenge of zoonotic malaria is immense and alerts to the need to conduct mitigation efforts through multidisciplinary approach involving environmental management, non-human primates conservation, disease management and vector control.
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Affiliation(s)
| | - Farahana Kresno Dewayanti
- Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia
| | - Lepa Syahrani
- Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia
| | - Dendi Hadi Permana
- Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia
| | - Ratmawati Malaka
- Faculty of Animal Husbandry, Hasanuddin University, Makassar, Indonesia
| | - Puji Budi Setia Asih
- Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia
| | - Din Syafruddin
- Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia
- Department of Parasitology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia
- Corresponding author at: Eijkman Institute for Molecular Biology, National Research and Innovation Agency, Jakarta, Indonesia.
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Ruiz Cuenca P, Key S, Lindblade KA, Vythilingam I, Drakeley C, Fornace K. Is there evidence of sustained human-mosquito-human transmission of the zoonotic malaria Plasmodium knowlesi? A systematic literature review. Malar J 2022; 21:89. [PMID: 35300703 PMCID: PMC8929260 DOI: 10.1186/s12936-022-04110-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/27/2022] [Indexed: 12/03/2022] Open
Abstract
Background The zoonotic malaria parasite Plasmodium knowlesi has emerged across Southeast Asia and is now the main cause of malaria in humans in Malaysia. A critical priority for P. knowlesi surveillance and control is understanding whether transmission is entirely zoonotic or is also occurring through human-mosquito-human transmission. Methods A systematic literature review was performed to evaluate existing evidence which refutes or supports the occurrence of sustained human-mosquito-human transmission of P. knowlesi. Possible evidence categories and study types which would support or refute non-zoonotic transmission were identified and ranked. A literature search was conducted on Medline, EMBASE and Web of Science using a broad search strategy to identify any possible published literature. Results were synthesized using the Synthesis Without Meta-analysis (SWiM) framework, using vote counting to combine the evidence within specific categories. Results Of an initial 7,299 studies screened, 131 studies were included within this review: 87 studies of P. knowlesi prevalence in humans, 14 studies in non-human primates, 13 studies in mosquitoes, and 29 studies with direct evidence refuting or supporting non-zoonotic transmission. Overall, the evidence showed that human-mosquito-human transmission is biologically possible, but there is limited evidence of widespread occurrence in endemic areas. Specific areas of research were identified that require further attention, notably quantitative analyses of potential transmission dynamics, epidemiological and entomological surveys, and ecological studies into the sylvatic cycle of the disease. Conclusion There are key questions about P. knowlesi that remain within the areas of research that require more attention. These questions have significant implications for malaria elimination and eradication programs. This paper considers limited but varied research and provides a methodological framework for assessing the likelihood of different transmission patterns for emerging zoonotic diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-022-04110-z.
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Affiliation(s)
- Pablo Ruiz Cuenca
- Centre for Health Informatics, Computing, and Statistics (CHICAS), Lancaster University Medical School, Lancaster, UK. .,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
| | - Stephanie Key
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Kim A Lindblade
- Global Malaria Programme, World Health Organization, Geneva, Switzerland
| | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, Universiti Malaya, 50603, Kuala Lumpur, Malaysia
| | - Chris Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Kimberly Fornace
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
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11
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Voinson M, Nunn CL, Goldberg A. Primate malarias as a model for cross-species parasite transmission. eLife 2022; 11:e69628. [PMID: 35086643 PMCID: PMC8798051 DOI: 10.7554/elife.69628] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 01/14/2022] [Indexed: 12/16/2022] Open
Abstract
Parasites regularly switch into new host species, representing a disease burden and conservation risk to the hosts. The distribution of these parasites also gives insight into characteristics of ecological networks and genetic mechanisms of host-parasite interactions. Some parasites are shared across many species, whereas others tend to be restricted to hosts from a single species. Understanding the mechanisms producing this distribution of host specificity can enable more effective interventions and potentially identify genetic targets for vaccines or therapies. As ecological connections between human and local animal populations increase, the risk to human and wildlife health from novel parasites also increases. Which of these parasites will fizzle out and which have the potential to become widespread in humans? We consider the case of primate malarias, caused by Plasmodium parasites, to investigate the interacting ecological and evolutionary mechanisms that put human and nonhuman primates at risk for infection. Plasmodium host switching from nonhuman primates to humans led to ancient introductions of the most common malaria-causing agents in humans today, and new parasite switching is a growing threat, especially in Asia and South America. Based on a wild host-Plasmodium occurrence database, we highlight geographic areas of concern and potential areas to target further sampling. We also discuss methodological developments that will facilitate clinical and field-based interventions to improve human and wildlife health based on this eco-evolutionary perspective.
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Affiliation(s)
- Marina Voinson
- Department of Evolutionary Anthropology, Duke UniversityDurhamUnited States
| | - Charles L Nunn
- Department of Evolutionary Anthropology, Duke UniversityDurhamUnited States
- Duke Global Health, Duke UniversityDurhamUnited States
| | - Amy Goldberg
- Department of Evolutionary Anthropology, Duke UniversityDurhamUnited States
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12
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Ahmed MA, Deshmukh GY, Zaidi RH, Saif A, Alshahrani MA, Wazid SW, Patgiri SJ, Quan FS. Identification, Mapping, and Genetic Diversity of Novel Conserved Cross-Species Epitopes of RhopH2 in Plasmodium knowlesi With Plasmodium vivax. Front Cell Infect Microbiol 2022; 11:810398. [PMID: 35096656 PMCID: PMC8793677 DOI: 10.3389/fcimb.2021.810398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 12/22/2021] [Indexed: 11/13/2022] Open
Abstract
Malaria is a major public health concern, and any tangible intervention during the pre-elimination phase can result in a significant reduction in infection rates. Recent studies have reported that antigens producing cross-protective immunity can play an important role as vaccines and halt malaria transmission in different endemic regions. In this study, we studied the genetic diversity, natural selection, and discovered novel conserved epitopes of a high molecular weight rhoptry protein 2 (RhopH2) in clinical samples of Plasmodium knowlesi and Plasmodium vivax cross-protective domains, which has been proven to produce cross-protective immunity in both species. We found low levels of nucleotide diversity (P. knowlesi; π ~ 0.0093, SNPs = 49 and P. vivax π ~ 0.0014, SNPs = 23) in P. knowlesi (n = 40) and P. vivax (n = 65) samples in the PkRhopH2 cross-protective domain. Strong purifying selection was observed for both species (P. knowlesi; dS - dN = 2.41, p < 0.009, P. vivax; dS - dN = 1.58, p < 0.050). In silico epitope prediction in P. knowlesi identified 10 potential epitopes, of which 7 epitopes were 100% conserved within clinical samples. Of these epitopes, an epitope with 10 amino acids (QNSKHFKKEK) was found to be fully conserved within all P. knowlesi and P. vivax clinical samples and 80%–90% conservation within simian malaria ortholog species, i.e., P. coatneyi and P. cynomolgi. Phylogenetic analysis of the PkRhopH2 cross-protective domain showed geographical clustering, and three subpopulations of P. knowlesi were identified of which two subpopulations originated from Sarawak, Malaysian Borneo, and one comprised only the laboratory lines from Peninsular Malaysia. This study suggests that RhopH2 could be an excellent target for cross-protective vaccine development with potential for outwitting strain as well as species-specific immunity. However, more detailed studies on genetic diversity using more clinical samples from both species as well as the functional role of antibodies specific to the novel conserved epitope identified in this study can be explored for protection against infection.
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Affiliation(s)
- Md Atique Ahmed
- Indian Council of Medical Research (ICMR)-Regional Medical Research Centre, North East Region (NER), Dibrugarh, India
- *Correspondence: Md Atique Ahmed, ; Fu-Shi Quan,
| | | | - Rehan Haider Zaidi
- Department of Biotechnology and Microbiology, National College, Tiruchirapalli, India
| | - Ahmed Saif
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Najran University, Narjan, Saudi Arabia
| | | | | | - Saurav Jyoti Patgiri
- Indian Council of Medical Research (ICMR)-Regional Medical Research Centre, North East Region (NER), Dibrugarh, India
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, South Korea
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, South Korea
- *Correspondence: Md Atique Ahmed, ; Fu-Shi Quan,
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13
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Hu TH, Rosli N, Mohamad DSA, Kadir KA, Ching ZH, Chai YH, Ideris NN, Ting LSC, Dihom AA, Kong SL, Wong EKY, Sia JEH, Ti T, Chai IPF, Tang WY, Hii KC, Divis PCS, Davis TME, Daneshvar C, Singh B. A comparison of the clinical, laboratory and epidemiological features of two divergent subpopulations of Plasmodium knowlesi. Sci Rep 2021; 11:20117. [PMID: 34635723 PMCID: PMC8505493 DOI: 10.1038/s41598-021-99644-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/24/2021] [Indexed: 11/25/2022] Open
Abstract
Plasmodium knowlesi, a simian malaria parasite responsible for all recent indigenous cases of malaria in Malaysia, infects humans throughout Southeast Asia. There are two genetically distinct subpopulations of Plasmodium knowlesi in Malaysian Borneo, one associated with long-tailed macaques (termed cluster 1) and the other with pig-tailed macaques (cluster 2). A prospective study was conducted to determine whether there were any between-subpopulation differences in clinical and laboratory features, as well as in epidemiological characteristics. Over 2 years, 420 adults admitted to Kapit Hospital, Malaysian Borneo with knowlesi malaria were studied. Infections with each subpopulation resulted in mostly uncomplicated malaria. Severe disease was observed in 35/298 (11.7%) of single cluster 1 and 8/115 (7.0%) of single cluster 2 infections (p = 0.208). There was no clinically significant difference in outcome between the two subpopulations. Cluster 1 infections were more likely to be associated with peri-domestic activities while cluster 2 were associated with interior forest activities consistent with the preferred habitats of the respective macaque hosts. Infections with both P. knowlesi subpopulations cause a wide spectrum of disease including potentially life-threatening complications, with no implications for differential patient management.
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Affiliation(s)
- Ting Huey Hu
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Nawal Rosli
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Dayang S A Mohamad
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Khamisah A Kadir
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | | | | | | | | | | | | | | | | | - Tiana Ti
- Kapit Hospital, Kapit, Sarawak, Malaysia
| | | | | | | | - Paul C S Divis
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Timothy M E Davis
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.,University of Western Australia, Medical School, Fremantle, WA, Australia
| | - Cyrus Daneshvar
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.,Department of Respiratory Medicine, University Hospitals Plymouth NHS Trust, Plymouth, UK
| | - Balbir Singh
- Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.
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14
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Cuenca PR, Key S, Jumail A, Surendra H, Ferguson HM, Drakeley CJ, Fornace K. Epidemiology of the zoonotic malaria Plasmodium knowlesi in changing landscapes. ADVANCES IN PARASITOLOGY 2021; 113:225-286. [PMID: 34620384 DOI: 10.1016/bs.apar.2021.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Within the past two decades, incidence of human cases of the zoonotic malaria Plasmodium knowlesi has increased markedly. P. knowlesi is now the most common cause of human malaria in Malaysia and threatens to undermine malaria control programmes across Southeast Asia. The emergence of zoonotic malaria corresponds to a period of rapid deforestation within this region. These environmental changes impact the distribution and behaviour of the simian hosts, mosquito vector species and human populations, creating new opportunities for P. knowlesi transmission. Here, we review how landscape changes can drive zoonotic disease emergence, examine the extent and causes of these changes across Southeast and identify how these mechanisms may be impacting P. knowlesi dynamics. We review the current spatial epidemiology of reported P. knowlesi infections in people and assess how these demographic and environmental changes may lead to changes in transmission patterns. Finally, we identify opportunities to improve P. knowlesi surveillance and develop targeted ecological interventions within these landscapes.
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Affiliation(s)
- Pablo Ruiz Cuenca
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Stephanie Key
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Henry Surendra
- Eijkman-Oxford Clinical Research Unit, Jakarta, Indonesia; Centre for Tropical Medicine, Faculty of Medicine, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Heather M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Chris J Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kimberly Fornace
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, United Kingdom.
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15
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Barber BE, Grigg MJ, Cooper DJ, van Schalkwyk DA, William T, Rajahram GS, Anstey NM. Clinical management of Plasmodium knowlesi malaria. ADVANCES IN PARASITOLOGY 2021; 113:45-76. [PMID: 34620385 DOI: 10.1016/bs.apar.2021.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The zoonotic parasite Plasmodium knowlesi has emerged as an important cause of human malaria in parts of Southeast Asia. The parasite is indistinguishable by microscopy from the more benign P. malariae, but can result in high parasitaemias with multiorgan failure, and deaths have been reported. Recognition of severe knowlesi malaria, and prompt initiation of effective therapy is therefore essential to prevent adverse outcomes. Here we review all studies reporting treatment of uncomplicated and severe knowlesi malaria. We report that although chloroquine is effective for the treatment of uncomplicated knowlesi malaria, artemisinin combination treatment is associated with faster parasite clearance times and lower rates of anaemia during follow-up, and should be considered the treatment of choice, particularly given the risk of administering chloroquine to drug-resistant P. vivax or P. falciparum misdiagnosed as P. knowlesi malaria in co-endemic areas. For severe knowlesi malaria, intravenous artesunate has been shown to be highly effective and associated with reduced case-fatality rates, and should be commenced without delay. Regular paracetamol may also be considered for patients with severe knowlesi malaria or for those with acute kidney injury, to attenuate the renal damage resulting from haemolysis-induced lipid peroxidation.
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Affiliation(s)
- Bridget E Barber
- QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia; Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia.
| | - Matthew J Grigg
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Daniel J Cooper
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia; Department of Medicine, University of Cambridge School of Medicine, Cambridge, United Kingdom
| | | | - Timothy William
- Gleneagles Medical Centre, Kota Kinabalu, Malaysia; Clinical Research Centre, Queen Elizabeth Hospital 1, Kota Kinabalu, Malaysia
| | - Giri S Rajahram
- Clinical Research Centre, Queen Elizabeth Hospital 1, Kota Kinabalu, Malaysia; Queen Elizabeth Hospital 2, Kota Kinabalu, Malaysia
| | - Nicholas M Anstey
- Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
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16
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Knowlesi malaria: Human risk factors, clinical spectrum, and pathophysiology. ADVANCES IN PARASITOLOGY 2021; 113:1-43. [PMID: 34620381 DOI: 10.1016/bs.apar.2021.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Plasmodium knowlesi is endemic across Southeast Asia, and is the commonest cause of zoonotic malaria. The spectrum of clinical disease from P. knowlesi infection ranges from asymptomatic infection, through to severe malaria and death. Over 90% of clinical disease occurs in adults, mostly living in forest edge areas undergoing intensive land use change. With a 24-h asexual life cycle in humans, high parasite counts are possible, but most clinical cases of knowlesi malaria are uncomplicated with low parasitaemia. In co-endemic areas, median parasitaemia in knowlesi malaria is lower than that seen in vivax and falciparum malaria, suggesting a lower fever threshold. Severe malaria occurs in 6-9% of symptomatic adults. Manifestations of severe malaria from P. knowlesi are similar to those seen with falciparum malaria, with the notable absence of coma. Age, parasitaemia, cardiovascular comorbidities and delayed diagnosis are risk factors for severe disease and death, which are only seen in adults. Thrombocytopenia is near-universal in adults, likely related to platelet-red cell binding and clearance. Mechanisms underlying the microvascular sludging seen in fatal disease in non-natural primate hosts and the microvascular accumulation of parasites in fatal human disease are not clear. Marked reductions in deformability of both infected and uninfected red blood cells are associated with disease severity in both humans and other non-natural primate hosts, likely contributing to impaired microvascular perfusion and organ dysfunction. Endothelial activation, endothelial dysfunction, glycocalyx degradation and haemolysis are also associated with, and likely contribute to, severe disease and organ dysfunction, particularly acute kidney injury.
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17
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Molecular epidemiology and population genomics of Plasmodium knowlesi. ADVANCES IN PARASITOLOGY 2021; 113:191-223. [PMID: 34620383 DOI: 10.1016/bs.apar.2021.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular epidemiology has been central to uncovering P. knowlesi as an important cause of human malaria in Southeast Asia, and to understanding the complex nature of this zoonosis. Species-specific parasite detection and characterization of sequences were vital to show that P. knowlesi was distinct from the human parasite species that had been presumed to cause all malaria. With established sensitive and specific molecular detection tools, surveys subsequently indicated the distribution of P. knowlesi infections in humans, wild primate reservoir host species, and mosquito vector species. The importance of studying P. knowlesi genetic polymorphism was indicated initially by analysing a few nuclear gene loci as well as the mitochondrial genome, and subsequently by multi-locus microsatellite analyses and whole-genome sequencing. Different human infections generally have unrelated P. knowlesi genotypes, acquired from the diverse local parasite reservoirs in macaques. However, individual human infections are usually less genetically complex than those of wild macaques which experience more frequent superinfection with different P. knowlesi genotypes. Multi-locus analyses have revealed deep population subdivisions within P. knowlesi, which are structured both geographically and in relation to different macaque reservoir host species. Simplified genotypic discrimination assays now enable efficient large-scale surveillance of the sympatric P. knowlesi subpopulations within Malaysian Borneo. The whole-genome sequence analyses have also identified loci under recent positive natural selection in the P. knowlesi genome, with evidence that different loci are affected in different populations. These provide a foundation to understand recent adaptation of the zoonotic parasite populations, and to track and interpret future changes as they emerge.
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18
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Divis PCS, Hu TH, Kadir KA, Mohammad DSA, Hii KC, Daneshvar C, Conway DJ, Singh B. Efficient Surveillance of Plasmodium knowlesi Genetic Subpopulations, Malaysian Borneo, 2000-2018. Emerg Infect Dis 2021; 26:1392-1398. [PMID: 32568035 PMCID: PMC7323547 DOI: 10.3201/eid2607.190924] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Population genetic analysis revealed that Plasmodium knowlesi infections in Malaysian Borneo are caused by 2 divergent parasites associated with long-tailed (cluster 1) and pig-tailed (cluster 2) macaques. Because the transmission ecology is likely to differ for each macaque species, we developed a simple genotyping PCR to efficiently distinguish between and survey the 2 parasite subpopulations. This assay confirmed differences in the relative proportions in areas of Kapit division of Sarawak state, consistent with multilocus microsatellite analyses. Analyses of 1,204 human infections at Kapit Hospital showed that cluster 1 caused approximately two thirds of cases with no significant temporal changes from 2000 to 2018. We observed an apparent increase in overall numbers in the most recent 2 years studied, driven mainly by increased cluster 1 parasite infections. Continued monitoring of the frequency of different parasite subpopulations and correlation with environmental alterations are necessary to determine whether the epidemiology will change substantially.
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19
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Hocking SE, Divis PCS, Kadir KA, Singh B, Conway DJ. Population Genomic Structure and Recent Evolution of Plasmodium knowlesi, Peninsular Malaysia. Emerg Infect Dis 2021; 26:1749-1758. [PMID: 32687018 PMCID: PMC7392424 DOI: 10.3201/eid2608.190864] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Most malaria in Malaysia is caused by Plasmodium knowlesi parasites through zoonotic infection from macaque reservoir hosts. We obtained genome sequences from 28 clinical infections in Peninsular Malaysia to clarify the emerging parasite population structure and test for evidence of recent adaptation. The parasites all belonged to a major genetic population of P. knowlesi (cluster 3) with high genomewide divergence from populations occurring in Borneo (clusters 1 and 2). We also observed unexpected local genetic subdivision; most parasites belonged to 2 subpopulations sharing a high level of diversity except at particular genomic regions, the largest being a region of chromosome 12, which showed evidence of recent directional selection. Surprisingly, we observed a third subpopulation comprising P. knowlesi infections that were almost identical to each other throughout much of the genome, indicating separately maintained transmission and recent genetic isolation. Each subpopulation could evolve and present a broader health challenge in Asia.
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20
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Goh XT, Lim YAL, Lee PC, Nissapatorn V, Chua KH. Diversity and natural selection of Merozoite surface Protein-1 in three species of human malaria parasites: Contribution from South-East Asian isolates. Mol Biochem Parasitol 2021; 244:111390. [PMID: 34087264 DOI: 10.1016/j.molbiopara.2021.111390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 05/28/2021] [Accepted: 05/28/2021] [Indexed: 11/19/2022]
Abstract
The present study aimed to examine the genetic diversity of human malaria parasites (i.e., P. falciparum, P. vivax and P. knowlesi) in Malaysia and southern Thailand targeting the 19-kDa C-terminal region of Merozoite Surface Protein-1 (MSP-119). This region is essential for the recognition and invasion of erythrocytes and it is considered one of the leading candidates for asexual blood stage vaccines. However, the genetic data of MSP-119 among human malaria parasites in Malaysia is limited and there is also a need to update the current sequence diversity of this gene region among the Thailand isolates. In this study, genomic DNA was extracted from 384 microscopy-positive blood samples collected from patients who attended the hospitals or clinics in Malaysia and malaria clinics in Thailand from the year 2008 to 2016. The MSP-119 was amplified using PCR followed by bidirectional sequencing. DNA sequences identified in the present study were subjected to Median-joining network analysis with sequences of MSP-119 obtained from GenBank. DNA sequence analysis revealed that PfMSP-119 of Malaysian and Thailand isolates was not genetically conserved as high number of haplotypes were detected and positive selection was prevalent in PfMSP-119, hence questioning its suitability to be used as a vaccine candidate. A novel haplotype (Q/TNG/L) was also detected in Thailand P. falciparum isolate. In contrast, PvMSP-119 was highly conserved, however for the first time, a non-synonymous substitution (A1657S) was reported among Malaysian isolates. As for PkMSP-119, the presence of purifying selection and low nucleotide diversity indicated that it might be a potential vaccine target for P. knowlesi.
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Affiliation(s)
- Xiang Ting Goh
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Yvonne A L Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Ping Chin Lee
- School of Science and Technology, University Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Veeranoot Nissapatorn
- Research Excellence Center for Innovation and Health Products (RECIHP) and School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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21
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New vectors that are early feeders for Plasmodium knowlesi and other simian malaria parasites in Sarawak, Malaysian Borneo. Sci Rep 2021; 11:7739. [PMID: 33833272 PMCID: PMC8032675 DOI: 10.1038/s41598-021-86107-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 03/09/2021] [Indexed: 02/01/2023] Open
Abstract
Plasmodium knowlesi is the main cause of malaria in Sarawak, where studies on vectors of P. knowlesi have been conducted in only two districts. Anopheles balabacensis and An. donaldi were incriminated as vectors in Lawas and An. latens in Kapit. We studied a third location in Sarawak, Betong, where of 2169 mosquitoes collected over 36 days using human-landing catches, 169 (7.8%) were Anopheles spp. PCR and phylogenetic analyses identified P. knowlesi and/or P. cynomolgi, P. fieldi, P. inui, P. coatneyi and possibly novel Plasmodium spp. in salivary glands of An. latens and An. introlatus from the Leucosphyrus Group and in An. collessi and An. roperi from the Umbrosus Group. Phylogenetic analyses of cytochrome oxidase subunit I sequences indicated three P. knowlesi-positive An. introlatus had been misidentified morphologically as An. latens, while An. collessi and An. roperi could not be delineated using the region sequenced. Almost all vectors from the Leucosphyrus Group were biting after 1800 h but those belonging to the Umbrosus Group were also biting between 0700 and 1100 h. Our study incriminated new vectors of knowlesi malaria in Sarawak and underscores the importance of including entomological studies during the daytime to obtain a comprehensive understanding of the transmission dynamics of malaria.
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22
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Oresegun DR, Daneshvar C, Cox-Singh J. Plasmodium knowlesi - Clinical Isolate Genome Sequencing to Inform Translational Same-Species Model System for Severe Malaria. Front Cell Infect Microbiol 2021; 11:607686. [PMID: 33738266 PMCID: PMC7960762 DOI: 10.3389/fcimb.2021.607686] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/27/2021] [Indexed: 12/03/2022] Open
Abstract
Malaria is responsible for unacceptably high morbidity and mortality, especially in Sub-Saharan African Nations. Malaria is caused by member species' of the genus Plasmodium and despite concerted and at times valiant efforts, the underlying pathophysiological processes leading to severe disease are poorly understood. Here we describe zoonotic malaria caused by Plasmodium knowlesi and the utility of this parasite as a model system for severe malaria. We present a method to generate long-read third-generation Plasmodium genome sequence data from archived clinical samples using the MinION platform. The method and technology are accessible, affordable and data is generated in real-time. We propose that by widely adopting this methodology important information on clinically relevant parasite diversity, including multiple gene family members, from geographically distinct study sites will emerge. Our goal, over time, is to exploit the duality of P. knowlesi as a well-used laboratory model and human pathogen to develop a representative translational model system for severe malaria that is informed by clinically relevant parasite diversity.
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Affiliation(s)
| | | | - Janet Cox-Singh
- Division of Infection, School of Medicine, University of St Andrews, St Andrews, United Kingdom
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Scott J. Proposed Integrated Control of Zoonotic Plasmodium knowlesi in Southeast Asia Using Themes of One Health. Trop Med Infect Dis 2020; 5:E175. [PMID: 33233871 PMCID: PMC7709578 DOI: 10.3390/tropicalmed5040175] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/15/2020] [Accepted: 11/18/2020] [Indexed: 01/28/2023] Open
Abstract
Zoonotic malaria, Plasmodium knowlesi, threatens the global progression of malaria elimination. Southeast Asian regions are fronting increased zoonotic malaria rates despite the control measures currently implemented-conventional measures to control human-malaria neglect P. knowlesi's residual transmission between the natural macaque host and vector. Initiatives to control P. knowlesi should adopt themes of the One Health approach, which details that the management of an infectious disease agent should be scrutinized at the human-animal-ecosystem interface. This review describes factors that have conceivably permitted the emergence and increased transmission rates of P. knowlesi to humans, from the understanding of genetic exchange events between subpopulations of P. knowlesi to the downstream effects of environmental disruption and simian and vector behavioral adaptations. These factors are considered to advise an integrative control strategy that aligns with the One Health approach. It is proposed that surveillance systems address the geographical distribution and transmission clusters of P. knowlesi and enforce ecological regulations that limit forest conversion and promote ecosystem regeneration. Furthermore, combining individual protective measures, mosquito-based feeding trapping tools and biocontrol strategies in synergy with current control methods may reduce mosquito population density or transmission capacity.
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Affiliation(s)
- Jessica Scott
- College of Public Health and Medical and Veterinary Sciences, Australian Institute of Tropical Health and Medicine, James Cook University, Townsville 4811, Australia
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24
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Kassegne K, Komi Koukoura K, Shen HM, Chen SB, Fu HT, Chen YQ, Zhou XN, Chen JH, Cheng Y. Genome-Wide Analysis of the Malaria Parasite Plasmodium falciparum Isolates From Togo Reveals Selective Signals in Immune Selection-Related Antigen Genes. Front Immunol 2020; 11:552698. [PMID: 33193320 PMCID: PMC7645038 DOI: 10.3389/fimmu.2020.552698] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 09/02/2020] [Indexed: 12/19/2022] Open
Abstract
Malaria is a public health concern worldwide, and Togo has proven to be no exception. Effective approaches to provide information on biological insights for disease elimination are therefore a research priority. Local selection on malaria pathogens is due to multiple factors including host immunity. We undertook genome-wide analysis of sequence variation on a sample of 10 Plasmodium falciparum (Pf) clinical isolates from Togo to identify local-specific signals of selection. Paired-end short-read sequences were mapped and aligned onto > 95% of the 3D7 Pf reference genome sequence in high fold coverage. Data on 266 963 single nucleotide polymorphisms were obtained, with average nucleotide diversity π = 1.79 × 10−3. Both principal component and neighbor-joining tree analyses showed that the Togo parasites clustered according to their geographic (Africa) origin. In addition, the average genome-wide diversity of Pf from Togo was much higher than that from other African samples. Tajima’s D value of the Togo isolates was −0.56, suggesting evidence of directional selection and/or recent population expansion. Against this background, within-population analyses identifying loci of balancing and recent positive selections evidenced that host immunity has been the major selective agent. Importantly, 87 and 296 parasite antigen genes with Tajima’s D values > 1 and in the top 1% haplotype scores, respectively, include a significant representation of membrane proteins at the merozoite stage that invaded red blood cells (RBCs) and parasitized RBCs surface proteins that play roles in immunoevasion, adhesion, or rosetting. This is consistent with expectations that elevated signals of selection due to allele-specific acquired immunity are likely to operate on antigenic targets. Collectively, our data suggest a recent expansion of Pf population in Togo and evidence strong host immune selection on membrane/surface antigens reflected in signals of balancing/positive selection of important gene loci. Findings from this study provide a fundamental basis to engage studies for effective malaria control in Togo.
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Affiliation(s)
- Kokouvi Kassegne
- Laboratory of Pathogen Infection and Immunity, Department of Public Health and Preventive Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
| | - Komi Komi Koukoura
- Laboratoire des Sciences Biomédicales, Alimentaires et Santé Environnementale, Département des Analyses Biomédicales, Ecole Supérieure des Techniques Biologiques et Alimentaires, Université de Lomé, Lomé, Togo
| | - Hai-Mo Shen
- National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention, Chinese Centre for Tropical Diseases Research, WHO Collaborating Centre for Tropical Diseases, National Centre for International Research on Tropical Diseases, Ministry of Science and Technology, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention-Shenzhen Centre for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China.,The School of Global Health, Chinese Centre for Tropical Diseases Research, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Shen-Bo Chen
- National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention, Chinese Centre for Tropical Diseases Research, WHO Collaborating Centre for Tropical Diseases, National Centre for International Research on Tropical Diseases, Ministry of Science and Technology, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention-Shenzhen Centre for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China.,The School of Global Health, Chinese Centre for Tropical Diseases Research, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Hai-Tian Fu
- Laboratory of Pathogen Infection and Immunity, Department of Public Health and Preventive Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
| | - Yong-Quan Chen
- Laboratory of Pathogen Infection and Immunity, Department of Public Health and Preventive Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China.,School of Food Science and Technology, State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention, Chinese Centre for Tropical Diseases Research, WHO Collaborating Centre for Tropical Diseases, National Centre for International Research on Tropical Diseases, Ministry of Science and Technology, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention-Shenzhen Centre for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China.,The School of Global Health, Chinese Centre for Tropical Diseases Research, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention, Chinese Centre for Tropical Diseases Research, WHO Collaborating Centre for Tropical Diseases, National Centre for International Research on Tropical Diseases, Ministry of Science and Technology, Key Laboratory of Parasite and Vector Biology, Ministry of Health, Shanghai, China.,National Institute of Parasitic Diseases, Chinese Centre for Disease Control and Prevention-Shenzhen Centre for Disease Control and Prevention Joint Laboratory for Imported Tropical Disease Control, Shanghai, China.,The School of Global Health, Chinese Centre for Tropical Diseases Research, Shanghai JiaoTong University School of Medicine, Shanghai, China
| | - Yang Cheng
- Laboratory of Pathogen Infection and Immunity, Department of Public Health and Preventive Medicine, Wuxi School of Medicine, Jiangnan University, Wuxi, China
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25
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Galinski MR. Functional genomics of simian malaria parasites and host-parasite interactions. Brief Funct Genomics 2020; 18:270-280. [PMID: 31241151 PMCID: PMC6859816 DOI: 10.1093/bfgp/elz013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/21/2019] [Accepted: 05/20/2019] [Indexed: 12/15/2022] Open
Abstract
Two simian malaria parasite species, Plasmodium knowlesi and Plasmodium cynomolgi, cause zoonotic infections in Southeast Asia, and they have therefore gained recognition among scientists and public health officials. Notwithstanding, these species and others including Plasmodium coatneyi have served for decades as sources of knowledge on the biology, genetics and evolution of Plasmodium, and the diverse ramifications and outcomes of malaria in their monkey hosts. Experimental analysis of these species can help to fill gaps in knowledge beyond what may be possible studying the human malaria parasites or rodent parasite species. The genome sequences for these simian malaria parasite species were reported during the last decade, and functional genomics research has since been pursued. Here research on the functional genomics analysis involving these species is summarized and their importance is stressed, particularly for understanding host–parasite interactions, and potentially testing novel interventions. Importantly, while Plasmodium falciparum and Plasmodium vivax can be studied in small New World monkeys, the simian malaria parasites can be studied more effectively in the larger Old World monkey macaque hosts, which are more closely related to humans. In addition to ex vivo analyses, experimental scenarios can include passage through Anopheline mosquito hosts and longitudinal infections in monkeys to study acute and chronic infections, as well as relapses, all in the context of the in vivo host environment. Such experiments provide opportunities for understanding functional genomic elements that govern host–parasite interactions, immunity and pathogenesis in-depth, addressing hypotheses not possible from in vitro cultures or cross-sectional clinical studies with humans.
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Affiliation(s)
- Mary R Galinski
- Emory Vaccine Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA.,Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
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26
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Ahmed MA, Saif A, Quan FS. Diversity pattern of Plasmodium knowlesi merozoite surface protein 4 (MSP4) in natural population of Malaysia. PLoS One 2019; 14:e0224743. [PMID: 31751362 PMCID: PMC6872184 DOI: 10.1371/journal.pone.0224743] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 10/21/2019] [Indexed: 01/20/2023] Open
Abstract
Human infections due to the monkey malaria parasite Plasmodium knowlesi are increasingly being reported from Malaysia. The parasite causes high parasitaemia, severe and fatal malaria in humans thus there is a need for urgent measures for its control. The MSP4 is a potential vaccine candidate, which is well studied in Plasmodium falciparum and Plasmodium vivax; however, no study has been conducted in the orthologous gene of P. knowlesi. In this study, we investigated the level of polymorphisms, haplotypes, natural selection and population structure of full-length pkmsp4 in 32 clinical samples from Malaysian Borneo along with 4 lab-adapted strains. We found low levels of polymorphism across the gene with exon I showing higher diversity than the exon II. The C- terminal epidermal growth factor (EGF) domains and GPI-anchored region within exon II were mostly conserved with only 2 non-synonymous substitutions. Although 21 amino acid haplotypes were found, the frequency of mutation at the majority of the polymorphic positions was low. We found evidence of negative selection at the exon II of the gene indicating existence of functional constraints. Phylogenetic haplotype network analysis identified shared haplotypes and indicated geographical clustering of samples originating from Peninsular Malaysia and Malaysian Borneo. High population differentiation values were observed within parasite populations originating from Malaysian Borneo (Kapit, Sarikei and Betong) and laboratory-adapted strains obtained from Peninsular Malaysia and Philippines indicating distinct population structure. This is the first study to genetically characterize the full-length msp4 gene from clinical isolates of P. knowlesi from Malaysia and thus would be very useful for future rational vaccine studies. Further studies with higher number of samples and functional characterization of the protein will be necessary.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Ahmed Saif
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Najran University, Najran, Saudi Arabia
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea.,Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate school, Kyung Hee University, Seoul, Republic of Korea
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27
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Atique Ahmed M, Kang HJ, Quan FS. Low Levels of Polymorphisms and Negative Selection in Plasmodum knowlesi Merozoite Surface Protein 8 in Malaysian Isolates. THE KOREAN JOURNAL OF PARASITOLOGY 2019; 57:445-450. [PMID: 31533414 PMCID: PMC6753297 DOI: 10.3347/kjp.2019.57.4.445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 07/17/2019] [Indexed: 11/23/2022]
Abstract
Human infections due to the monkey malaria parasite Plasmodium knowlesi is increasingly being reported from most Southeast Asian countries specifically Malaysia. The parasite causes severe and fatal malaria thus there is a need for urgent measures for its control. In this study, the level of polymorphisms, haplotypes and natural selection of full-length pkmsp8 in 37 clinical samples from Malaysian Borneo along with 6 lab-adapted strains were investigated. Low levels of polymorphism were observed across the full-length gene, the double epidermal growth factor (EGF) domains were mostly conserved, and non-synonymous substitutions were absent. Evidence of strong negative selection pressure in the non-EGF regions were found indicating functional constrains acting at different domains. Phylogenetic haplotype network analysis identified shared haplotypes and indicated geographical clustering of samples originating from Peninsular Malaysia and Malaysian Borneo. This is the first study to genetically characterize the full-length msp8 gene from clinical isolates of P. knowlesi from Malaysia; however, further functional characterization would be useful for future rational vaccine design.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Hae-Ji Kang
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Korea.,Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
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28
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Wilcox JS, Kerschner A, Hollocher H. Indel-informed Bayesian analysis suggests cryptic population structure between Plasmodium knowlesi of humans and long-tailed macaques (Macaca fascicularis) in Malaysian Borneo. INFECTION GENETICS AND EVOLUTION 2019; 75:103994. [PMID: 31421245 DOI: 10.1016/j.meegid.2019.103994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 08/01/2019] [Accepted: 08/03/2019] [Indexed: 01/02/2023]
Abstract
Plasmodium knowlesi is an important causative agent of malaria in humans of Southeast Asia. Macaques are natural hosts for this parasite, but little is conclusively known about its patterns of transmission within and between these hosts. Here, we apply a comprehensive phylogenetic approach to test for patterns of cryptic population genetic structure between P. knowlesi isolated from humans and long-tailed macaques from the state of Sarawak in Malaysian Borneo. Our approach differs from previous investigations through our exhaustive use of archival 18S Small Subunit rRNA (18S) gene sequences from Plasmodium and Hepatocystis species, our inclusion of insertion and deletion information during phylogenetic inference, and our application of Bayesian phylogenetic inference to this problem. We report distinct clades of P. knowlesi that predominantly contained sequences from either human or macaque hosts for paralogous A-type and S-type 18S gene loci. We report significant partitioning of sequence distances between host species across both types of loci, and confirmed that sequences of the same locus type showed significantly biased assortment into different clades depending on their host species. Our results support the zoonotic potential of Plasmodium knowlesi, but also suggest that humans may be preferentially infected with certain strains of this parasite. Broadly, such patterns could arise through preferential zoonotic transmission of some parasite lineages or a disposition of parasites to transmit within, rather than between, human and macaque hosts. Available data are insufficient to address these hypotheses. Our results suggest that the epidemiology of P. knowlesi may be more complicated than previously assumed, and highlight the need for renewed and more vigorous explorations of transmission patterns in the fifth human malarial parasite.
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Affiliation(s)
- JustinJ S Wilcox
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA.
| | - Abigail Kerschner
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA
| | - Hope Hollocher
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA
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29
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Benavente ED, Gomes AR, De Silva JR, Grigg M, Walker H, Barber BE, William T, Yeo TW, de Sessions PF, Ramaprasad A, Ibrahim A, Charleston J, Hibberd ML, Pain A, Moon RW, Auburn S, Ling LY, Anstey NM, Clark TG, Campino S. Whole genome sequencing of amplified Plasmodium knowlesi DNA from unprocessed blood reveals genetic exchange events between Malaysian Peninsular and Borneo subpopulations. Sci Rep 2019; 9:9873. [PMID: 31285495 PMCID: PMC6614422 DOI: 10.1038/s41598-019-46398-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 06/28/2019] [Indexed: 12/19/2022] Open
Abstract
The zoonotic Plasmodium knowlesi parasite is the most common cause of human malaria in Malaysia. Genetic analysis has shown that the parasites are divided into three subpopulations according to their geographic origin (Peninsular or Borneo) and, in Borneo, their macaque host (Macaca fascicularis or M. nemestrina). Whilst evidence suggests that genetic exchange events have occurred between the two Borneo subpopulations, the picture is unclear in less studied Peninsular strains. One difficulty is that P. knowlesi infected individuals tend to present with low parasitaemia leading to samples with insufficient DNA for whole genome sequencing. Here, using a parasite selective whole genome amplification approach on unprocessed blood samples, we were able to analyse recent genomes sourced from both Peninsular Malaysia and Borneo. The analysis provides evidence that recombination events are present in the Peninsular Malaysia parasite subpopulation, which have acquired fragments of the M. nemestrina associated subpopulation genotype, including the DBPβ and NBPXa erythrocyte invasion genes. The NBPXb invasion gene has also been exchanged within the macaque host-associated subpopulations of Malaysian Borneo. Our work provides strong evidence that exchange events are far more ubiquitous than expected and should be taken into consideration when studying the highly complex P. knowlesi population structure.
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Affiliation(s)
- Ernest Diez Benavente
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ana Rita Gomes
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Centre Hospitalier Universitaire de Montpellier, Montpellier, France
| | | | - Matthew Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Harriet Walker
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia.,Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, 88300, Kota Kinabalu, Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, 88300, Kota Kinabalu, Sabah, Malaysia.,Clinical Research Centre, Queen Elizabeth Hospital, 88300, Kota Kinabalu, Sabah, Malaysia.,Jesselton Medical Centre, 88300, Kota Kinabalu, Sabah, Malaysia
| | - Tsin Wen Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | | | - Abhinay Ramaprasad
- King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Amy Ibrahim
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - James Charleston
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin L Hibberd
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Genomics Institute, Biopolis, Singapore
| | - Arnab Pain
- King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Robert W Moon
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Sarah Auburn
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | | | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Taane G Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom. .,Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.
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30
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Saleh Huddin A, Md Yusuf N, Razak MRMA, Ogu Salim N, Hisam S. Genetic diversity of Plasmodium knowlesi among human and long-tailed macaque populations in Peninsular Malaysia: The utility of microsatellite markers. INFECTION GENETICS AND EVOLUTION 2019; 75:103952. [PMID: 31279818 DOI: 10.1016/j.meegid.2019.103952] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/29/2019] [Accepted: 07/03/2019] [Indexed: 11/16/2022]
Abstract
It has been discovered that Plasmodium knowlesi (P. knowlesi) is transmitted from macaque to man. Thus, the aim of the present study was to determine P. knowlesi genetic diversity in both human (n = 147) and long-tailed macaque (n = 26) samples from high- and low-endemicity localities. Genotyping was performed using seven neutral microsatellite loci markers. The size of the alleles, multiplicity of infection (MOI), mean number of alleles (Na), expected heterozygosity (HE), linkage disequilibrium (LD), and genetic differentiation (FST) were determined. In highly endemic P. knowlesi localities, the MOI for human and long-tailed macaque isolates was 1.04 and 1.15, respectively, while the Na was 11.14 and 7.86, respectively. Based on the allele frequency distribution for all loci, and with FST < 0.1, no genetic differentiation was seen between human and long-tailed macaque. In localities characterised by lower P. knowlesi endemicity, the MOI for human and long-tailed macaque isolates was 1.05 and 1.11, respectively, while the Na was 6.14 and 2.71, respectively. Further molecular analysis of the allele frequencies indicated that there was a significant genetic differentiation in human P. knowlesi isolates as compared to long-tailed macaque isolates, with a very low fixation index (FST = 0.016, p < .05) based on multiple loci analysis. Our results further indicate that, in Peninsular Malaysia, humans are mostly affected by P. knowlesi of a single genotype, while long-tailed macaque tend to acquire polyclonal infections, which supports the assumption that there is a higher rate of transmission among long-tailed macaque. Understanding the genetic diversity of P. knowlesi isolates can provide invaluable information for characterising patterns of the population structure and the migration rate of P. knowlesi in peninsular Malaysia.
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Affiliation(s)
- Afiqah Saleh Huddin
- Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Malaysia
| | - NoorAzian Md Yusuf
- Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Malaysia.
| | | | - Nurhainis Ogu Salim
- Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Malaysia
| | - Shamilah Hisam
- Parasitology Unit, Infectious Disease Research Centre, Institute for Medical Research, Jalan Pahang, 50588 Kuala Lumpur, Malaysia
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31
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Ahmed MA, Quan FS. Plasmodium knowlesi clinical isolates from Malaysia show extensive diversity and strong differential selection pressure at the merozoite surface protein 7D (MSP7D). Malar J 2019; 18:150. [PMID: 31035999 PMCID: PMC6489361 DOI: 10.1186/s12936-019-2782-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 04/16/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The high proportion of human cases due to the simian malaria parasite Plasmodium knowlesi in Malaysia is a cause of concern, as they can be severe and even fatal. Merozoite surface protein 7 (MSP7) is a multigene family which forms a non-covalent complex with MSP-1 prior to receptor-ligand recognition in Plasmodium falciparum and thus an important antigen for vaccine development. However, no study has been done in any of the ortholog family members in P. knowlesi from clinical samples. This study investigates the level of polymorphism, haplotypes, and natural selection acting at the pkmsp-7D gene in clinical samples from Malaysia. METHODS Thirty-six full-length pkmsp7D gene sequences (along with the reference H-strain: PKNH_1266000) obtained from clinical isolates of Malaysia, which were orthologous to pvmsp7H (PVX_082680) were downloaded from public databases. Population genetic, evolutionary and phylogenetic analyses were performed to determine the level of genetic diversity, polymorphism, recombination and natural selection. RESULTS Analysis of 36 full-length pkmsp7D sequences identified 147 SNPs (91 non-synonymous and 56 synonymous substitutions). Nucleotide diversity across the full-length gene was higher than its ortholog in Plasmodium vivax (msp7H). Region-wise analysis of the gene indicated that the nucleotide diversity at the central region was very high (π = 0.14) compared to the 5' and 3' regions. Most hyper-variable SNPs were detected at the central domain. Multiple test for natural selection indicated the central region was under strong positive natural selection however, the 5' and 3' regions were under negative/purifying selection. Evidence of intragenic recombination were detected at the central region of the gene. Phylogenetic analysis using full-length msp7D genes indicated there was no geographical clustering of parasite population. CONCLUSIONS High genetic diversity with hyper-variable SNPs and strong evidence of positive natural selection at the central region of MSP7D indicated exposure of the region to host immune pressure. Negative selection at the 5' and the 3' regions of MSP7D might be because of functional constraints at the unexposed regions during the merozoite invasion process of P. knowlesi. No evidence of geographical clustering among the clinical isolates from Malaysia indicated uniform selection pressure in all populations. These findings highlight the further evaluation of the regions and functional characterization of the protein as a potential blood stage vaccine candidate for P. knowlesi.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea. .,Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul, Republic of Korea.
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32
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Davidson G, Chua TH, Cook A, Speldewinde P, Weinstein P. Defining the ecological and evolutionary drivers of Plasmodium knowlesi transmission within a multi-scale framework. Malar J 2019; 18:66. [PMID: 30849978 PMCID: PMC6408765 DOI: 10.1186/s12936-019-2693-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 03/01/2019] [Indexed: 01/12/2023] Open
Abstract
Plasmodium knowlesi is a zoonotic malaria parasite normally residing in long-tailed and pig-tailed macaques (Macaca fascicularis and Macaca nemestrina, respectively) found throughout Southeast Asia. Recently, knowlesi malaria has become the predominant malaria affecting humans in Malaysian Borneo, being responsible for approximately 70% of reported cases. Largely as a result of anthropogenic land use changes in Borneo, vectors which transmit the parasite, along with macaque hosts, are both now frequently found in disturbed forest habitats, or at the forest fringes, thus having more frequent contact with humans. Having access to human hosts provides the parasite with the opportunity to further its adaption to the human immune system. The ecological drivers of the transmission and spread of P. knowlesi are operating over many different spatial (and, therefore, temporal) scales, from the molecular to the continental. Strategies to prevent and manage zoonoses, such as P. knowlesi malaria require interdisciplinary research exploring the impact of land use change and biodiversity loss on the evolving relationship between parasite, reservoir hosts, vectors, and humans over multiple spatial scales.
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Affiliation(s)
- Gael Davidson
- School of Agriculture and Environment, University of Western Australia, Stirling Terrace, Albany, WA, 6330, Australia. .,School of Population and Global Health, University of Western Australia, Perth, Australia.
| | - Tock H Chua
- Faculty of Medicine and Health Sciences, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia
| | - Angus Cook
- School of Population and Global Health, University of Western Australia, Perth, Australia
| | - Peter Speldewinde
- School of Agriculture and Environment, University of Western Australia, Stirling Terrace, Albany, WA, 6330, Australia
| | - Philip Weinstein
- School of Biological Sciences, University of Adelaide, Adelaide, Australia
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Ahmed MA, Chu KB, Quan FS. The Plasmodium knowlesi Pk41 surface protein diversity, natural selection, sub population and geographical clustering: a 6-cysteine protein family member. PeerJ 2018; 6:e6141. [PMID: 30581686 PMCID: PMC6296336 DOI: 10.7717/peerj.6141] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 11/20/2018] [Indexed: 12/05/2022] Open
Abstract
Introduction The zoonotic malaria parasite Plasmodium knowlesi has currently become the most dominant form of infection in humans in Malaysia and is an emerging infectious disease in most Southeast Asian countries. The P41 is a merozoite surface protein belonging to the 6-cysteine family and is a well-characterized vaccine candidate in P. vivax and P. falciparum; however, no study has been done in the orthologous gene of P. knowlesi. This study investigates the level of polymorphism, haplotypes and natural selection of pk41 genes in clinical isolates from Malaysia. Method Thirty-five full-length pk41 sequences from clinical isolates of Malaysia along with four laboratory lines (along with H-strain) were downloaded from public databases. For comparative analysis between species, orthologous P41 genes from P. falciparum, P. vivax, P. coatneyi and P. cynomolgi were also downloaded. Genetic diversity, polymorphism, haplotype and natural selection were determined using DnaSP 5.10 software. Phylogenetic relationships between Pk41 genes were determined using MEGA 5.0 software. Results Analysis of 39 full-length pk41 sequences along with the H-strain identified 36 SNPs (20 non-synonymous and 16 synonymous substitutions) resulting in 31 haplotypes. Nucleotide diversity across the full-length gene was low and was similar to its ortholog in P. vivax; pv41. Domain-wise amino acid analysis of the two s48/45 domains indicated low level of polymorphisms for both the domains, and the glutamic acid rich region had extensive size variations. In the central domain, upstream to the glutamate rich region, a unique two to six (K-E)n repeat region was identified within the clinical isolates. Overall, the pk41 genes were indicative of negative/purifying selection due to functional constraints. Domain-wise analysis of the s48/45 domains also indicated purifying selection. However, analysis of Tajima’s D across the genes identified non-synonymous SNPs in the s48/45 domain II with high positive values indicating possible epitope binding regions. All the 6-cysteine residues within the s48/45 domains were conserved within the clinical isolates indicating functional conservation of these regions. Phylogenetic analysis of full-length pk41 genes indicated geographical clustering and identified three subpopulations of P. knowlesi; one originating in the laboratory lines and two originating from Sarawak, Malaysian Borneo. Conclusion This is the first study to report on the polymorphism and natural selection of pk41 genes from clinical isolates of Malaysia. The results reveal that there is low level of polymorphism in both s48/45 domains, indicating that this antigen could be a potential vaccine target. However, genetic and molecular immunology studies involving higher number of samples from various parts of Malaysia would be necessary to validate this antigen’s candidacy as a vaccine target for P. knowlesi.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea.,Biomedical Science Institute, Kyung Hee University, Seoul, Republic of Korea
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Yap NJ, Vythilingam I, Hoh BP, Goh XT, Muslim A, Ngui R, Rajoo Y, Choy SH, William T, Yeo TW, Lim YAL. Genetic polymorphism and natural selection in the C-terminal 42 kDa region of merozoite surface protein-1 (MSP-1) among Plasmodium knowlesi samples from Malaysia. Parasit Vectors 2018; 11:626. [PMID: 30518419 PMCID: PMC6282282 DOI: 10.1186/s13071-018-3234-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/26/2018] [Indexed: 12/19/2022] Open
Abstract
Background The merozoite surface protein-1 (MSP-1) gene encodes for a leading malaria vaccine candidate antigen. However, its extensive polymorphic nature represents a major obstacle to the development of a protective vaccine. Previously, a pilot study was carried out to explore the sequence variation of the C-terminal 42 kDa fragment within P. knowlesi MSP-1 gene (PkMSP-142) based on 12 clinical samples; however, further study on an adequate sample size is vital in estimating the genetic diversity of the parasite population. Methods In the present study, we included a larger sample size of P. knowlesi (83 samples) covering eight states of Malaysia to determine the genetic polymorphism, natural selection and haplotype groups of the gene fragment coding PkMSP-142. The region flanking PkMSP-142 was amplified by PCR and directly sequenced. Genetic diversity, haplotype diversity, population genetic differentiation and natural selection were determined in order to study the polymorphic characteristic of PkMSP-142. Results A high level of genetic diversity (Hd = 0.970 ± 0.007; л = 0.01079 ± 0.00033) was observed among the 83 P. knowlesi samples, confirming the extensive genetic polymorphism exhibited among the P. knowlesi population found in Malaysia. A total of 18 distinct haplotypes with 17 amino acid changes were identified, whereby 15 were new haplotypes. High population differentiation values were observed within samples from Peninsular Malaysia and Malaysian Borneo. The 42 kDa fragments of P. knowlesi from Malaysian Borneo were found to be acting on balancing selection whilst purifying selection was suggested to act on isolates from Peninsular Malaysia. The separation of PkMSP-142 haplotypes into two main groups based on geographical separation has further supported the existence of two distinct P. knowlesi lineages. Conclusions A high level of genetic diversity was observed among PkMSP-142 in Malaysia, whereby most of the polymorphisms were found within the 33 kDa region. Taken together, these data will be useful in order to understand the nature of P. knowlesi population in Malaysia as well as the design and development of a MSP-142 based knowlesi malaria vaccine. Electronic supplementary material The online version of this article (10.1186/s13071-018-3234-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nan Jiun Yap
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Indra Vythilingam
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Boon Peng Hoh
- Faculty of Medicine & Health Sciences, UCSI University Kuala Lumpur Campus, Cheras, Kuala Lumpur, Malaysia
| | - Xiang Ting Goh
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Azdayanti Muslim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.,Department of Medical Microbiology and Parasitology, Faculty of Medicine, Universiti Teknologi MARA (Sungai Buloh Campus), Sungai Buloh, Selangor, Malaysia
| | - Romano Ngui
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Yamuna Rajoo
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia.,International Medical University, Bukit Jalil, Kuala Lumpur, Malaysia
| | - Seow Huey Choy
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Timothy William
- Jesselton Medical Centre, 88300, Kota Kinabalu, Sabah, Malaysia
| | - Tsin Wen Yeo
- Communicable Diseases Centre, Institute of Infectious Disease and Epidemiology, Tan Tock Seng Hospital, Moulmein Road, Singapore, 308433, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, 11 Mandalay Road, Singapore, 308232, Singapore
| | - Yvonne Ai-Lian Lim
- Department of Parasitology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia. .,Centre of Excellence for Research in AIDS (CERiA), University of Malaya, 50603, Kuala Lumpur, Malaysia.
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Ahmed MA, Chu KB, Vythilingam I, Quan FS. Within-population genetic diversity and population structure of Plasmodium knowlesi merozoite surface protein 1 gene from geographically distinct regions of Malaysia and Thailand. Malar J 2018; 17:442. [PMID: 30497496 PMCID: PMC6267868 DOI: 10.1186/s12936-018-2583-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/21/2018] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The C-terminal 42 kDa domain of Plasmodium knowlesi merozoite surface protein 1 (PkMSP1) is a potential asexual blood-stage vaccine candidate, however, only a limited number of clinical isolates have been analysed from Malaysia and no inter-country comparative diversity study has been conducted. In the present study, nucleotide diversity, haplotypes and natural selection levels of pkmsp1 in clinical samples from geographically distinct regions of Malaysia and Thailand were investigated. The overall population structure of the parasite from the region was determined. METHODS Eleven full-length pkmsp1 sequences obtained from clinical isolates of Malaysia along with the H-strain were downloaded from the database for domain wise characterization of pkmsp1 gene. Additionally, 76 pkmsp-142 sequences from Thailand and Malaysia were downloaded from the database for intra and inter-population analysis. DnaSP 5.10 and MEGA 5.0 software were used to determine genetic diversity, polymorphism, haplotypes and natural selection. Genealogical relationships were determined using haplotype network tree in NETWORK software v5.0. Population genetic differentiation index (FST) of parasites were analysed using Arlequin v3.5. RESULTS Sequence analysis of 11 full-length pkmsp1 sequences along with the H-strain identified 477 (8.4%) polymorphic sites, of which 107 were singleton sites. The overall diversity observed in the full-length genes were high in comparison to its ortholog pvmsp1 and the 4 variable domains showed extensive size variations. The nucleotide diversity was low towards the pkmsp1-42 compared to the conserved domains. The 19 kDa domain was less diverse and completely conserved among isolates from Malaysian Borneo. The nucleotide diversity of isolates from Peninsular Malaysia and Thailand were higher than Malaysian Borneo. Network analysis of pkmsp1-42 haplotypes showed geographical clustering of the isolates from Malaysian Borneo and grouping of isolates from Peninsular Malaysia and Thailand. Population differentiation analysis indicated high FST values between parasite populations originating from Malaysian Borneo, Peninsular Malaysia and Thailand attributing to geographical distance. Moderate genetic differentiation was observed for parasite populations from Thailand and Peninsular Malaysia. Evidence of population expansion and purifying selection were observed in all conserved domains with strongest selection within the pkmsp1-42 domain. CONCLUSIONS This study is the first to report on inter country genetic diversity and population structure of P. knowlesi based on msp1. Strong evidence of negative selection was observed in the 42 kDa domain, indicating functional constrains. Geographical clustering of P. knowlesi and moderate to high genetic differentiation values between populations identified in this study highlights the importance of further evaluation using larger number of clinical samples from Southeast Asian countries.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Indra Vythilingam
- Parasitology Department, University of Malaya, Kuala Lumpur, Malaysia
| | - Fu-Shi Quan
- Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea. .,Biomedical Science Institute, Kyung Hee University, Seoul, 02447, Republic of Korea.
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Wilcox JJS, Kerschner A, Hollocher H. WITHDRAWN: Indel-informed bayesian analysis suggests cryptic divisions between Plasmodium knowlesi of humans and long-tailed macaques (Macaca fascicularis) in Malaysian Borneo. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2018:S1567-1348(18)30557-4. [PMID: 30481580 DOI: 10.1016/j.meegid.2018.11.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 10/24/2018] [Accepted: 11/23/2018] [Indexed: 06/09/2023]
Abstract
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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Affiliation(s)
- Justin J S Wilcox
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA.
| | - Abigail Kerschner
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA
| | - Hope Hollocher
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5688, USA
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Plasmodium genomics: an approach for learning about and ending human malaria. Parasitol Res 2018; 118:1-27. [PMID: 30402656 DOI: 10.1007/s00436-018-6127-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/19/2018] [Indexed: 12/31/2022]
Abstract
Malaria causes high levels of morbidity and mortality in human beings worldwide. According to the World Health Organization (WHO), about half a million people die of this disease each year. Malaria is caused by six species of parasites belonging to the Plasmodium genus: P. falciparum, P. knowlesi, P. vivax, P. malariae, P. ovale curtisi, and P. ovale wallikeri. Currently, malaria is being kept under control with varying levels of elimination success in different countries. The development of new molecular tools as well as the use of next-generation sequencing (NGS) technologies and novel bioinformatic approaches has improved our knowledge of malarial epidemiology, diagnosis, treatment, vaccine development, and surveillance strategies. In this work, the genetics and genomics of human malarias have been analyzed. Since the first P. falciparum genome was sequenced in 2002, various population-level genetic and genomic surveys, together with transcriptomic and proteomic studies, have shown the importance of molecular approaches in supporting malaria elimination.
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Amir A, Cheong FW, de Silva JR, Liew JWK, Lau YL. Plasmodium knowlesi malaria: current research perspectives. Infect Drug Resist 2018; 11:1145-1155. [PMID: 30127631 PMCID: PMC6089103 DOI: 10.2147/idr.s148664] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Originally known to cause simian malaria, Plasmodium knowlesi is now known as the fifth human malaria species. Since the publishing of a report that largely focused on human knowlesi cases in Sarawak in 2004, many more human cases have been reported in nearly all of the countries in Southeast Asia and in travelers returning from these countries. The zoonotic nature of this infection hinders malaria elimination efforts. In order to grasp the current perspective of knowlesi malaria, this literature review explores the different aspects of the disease including risk factors, diagnosis, treatment, and molecular and functional studies. Current studies do not provide sufficient data for an effective control program. Therefore, future direction for knowlesi research is highlighted here with a final aim of controlling, if not eliminating, the parasite.
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Affiliation(s)
- Amirah Amir
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia,
| | - Fei Wen Cheong
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia,
| | - Jeremy Ryan de Silva
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia,
| | - Jonathan Wee Kent Liew
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia,
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia,
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Ahmed MA, Lau YL, Quan FS. Diversity and natural selection on the thrombospondin-related adhesive protein (TRAP) gene of Plasmodium knowlesi in Malaysia. Malar J 2018; 17:274. [PMID: 30053885 PMCID: PMC6062916 DOI: 10.1186/s12936-018-2423-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 07/19/2018] [Indexed: 11/17/2022] Open
Abstract
Background Plasmodium knowlesi a parasite of the macaques is currently the most common cause of human malaria in Malaysia. The thrombospondin-related adhesive protein (TRAP) gene is pre-erythrocytic stage antigen. It is a well-characterized vaccine candidate in Plasmodium vivax and Plasmodium falciparum, however, no study has been done in the orthologous gene of P. knowlesi. This study investigates nucleotide diversity, haplotypes, natural selection and population differentiation of full-length pktrap genes in clinical samples from Malaysia. Methods Forty full-length pktrap sequences from clinical isolates of Malaysia along with the reference H-strain were downloaded from published databases. Genetic diversity, polymorphism, haplotype and natural selection were determined using DnaSP 5.10 software. McDonald–Kreitman test was conducted using P. vivax and Plasmodium coatneyi as ortholog sequence in DnaSP 5.10 software. Population genetic differentiation index (FST) of parasite populations was determined using Arlequin v3.5. Phylogenetic relationships between trap ortholog genes were determined using MEGA 5.0 software. Results Comparison of 40 full-length pktrap sequences along with the H-strain identified 74 SNPs (53 non-synonymous and 21 synonymous substitutions) resulting in 29 haplotypes. Analysis of the full-length gene showed that the nucleotide diversity was lower compared to its nearest ortholog pvtrap. Domain-wise analysis indicated that the proline/asparagine rich region had higher nucleotide diversity compared to the von Willebrand factor domain and the thrombospondin-type-1 domain. McDonald–Kreitman test identified that the ratio of the number of nonsynonymous to synonymous polymorphic sites within P. knowlesi was significantly higher than that of the number of nonsynonymous to synonymous fixed sites between P. knowlesi and P. vivax. The von Willebrand factor domain also indicated balancing selection using MK test, however, it did not give significant results when tested with P. coatneyi as an outgroup. Phylogenetic analysis of full-length genes identified three distinct sub-clusters of P. knowlesi, one originating from Peninsular Malaysia and two originating from Malaysian Borneo. High population differentiation values was observed within samples from Peninsular Malaysia and Malaysian Borneo. Conclusions This study is the first to report on the genetic diversity and natural selection of full-length pktrap. Low level of genetic diversity was found across the full-length gene of pktrap. Balancing selection of the von Willebrand factor domain indicated that TRAP could be a target in inducing immune response against P. knowlesi infections. However, higher number of samples would be necessary to further confirm the findings. Electronic supplementary material The online version of this article (10.1186/s12936-018-2423-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Md Atique Ahmed
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, 130-705, South Korea
| | - Yee Ling Lau
- Department of Parasitology, University of Malaya, Kuala Lumpur, Malaysia
| | - Fu-Shi Quan
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul, 130-705, South Korea. .,Biomedical Science Institute, Kyung Hee University, Seoul, 130-705, South Korea.
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van Schalkwyk DA, Moon RW, Blasco B, Sutherland CJ. Comparison of the susceptibility of Plasmodium knowlesi and Plasmodium falciparum to antimalarial agents. J Antimicrob Chemother 2018; 72:3051-3058. [PMID: 28961865 PMCID: PMC5890772 DOI: 10.1093/jac/dkx279] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 07/11/2017] [Indexed: 01/09/2023] Open
Abstract
Background The simian malaria parasite Plasmodium knowlesi is now a well-recognized pathogen of humans in South-East Asia. Clinical infections appear adequately treated with existing drug regimens, but the evidence base for this practice remains weak. The availability of P. knowlesi cultures adapted to continuous propagation in human erythrocytes enables specific studies of in vitro susceptibility of the species to antimalarial agents, and could provide a surrogate system for testing investigational compounds against Plasmodium vivax and other non-Plasmodium falciparum infections that cannot currently be propagated in vitro. Objectives We sought to optimize protocols for in vitro susceptibility testing of P. knowlesi and to contrast outputs with those obtained for P. falciparum under comparable test conditions. Methods Growth monitoring of P. knowlesi in vitro was by DNA quantification using a SYBR Green fluorescent assay or by colorimetric detection of the lactate dehydrogenase enzyme. For comparison, P. falciparum was tested under conditions identical to those used for P. knowlesi. Results The SYBR Green I assay proved the most robust format over one (27 h) or two (54 h) P. knowlesi life cycles. Unexpectedly, P. knowlesi displays significantly greater susceptibility to the dihydrofolate reductase inhibitors pyrimethamine, cycloguanil and trimethoprim than does P. falciparum, but is less susceptible to the selective agents blasticidin and DSM1 used in parasite transfections. Inhibitors of dihydroorotate dehydrogenase also demonstrate lower activity against P. knowlesi. Conclusions The fluorescent assay system validated here identified species-specific P. knowlesi drug susceptibility profiles and can be used for testing investigational compounds for activity against non-P. falciparum malaria.
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Affiliation(s)
- Donelly A van Schalkwyk
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Robert W Moon
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Benjamin Blasco
- Medicines for Malaria Venture, 20 rte de Pré Bois, Geneva CH 1215, Switzerland
| | - Colin J Sutherland
- Department of Immunology & Infection, Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK.,Department of Clinical Parasitology, Hospital for Tropical Diseases, Mortimer Market Centre, Capper Street, London WC1E 6JB, UK
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Herman LS, Fornace K, Phelan J, Grigg MJ, Anstey NM, William T, Moon RW, Blackman MJ, Drakeley CJ, Tetteh KKA. Identification and validation of a novel panel of Plasmodium knowlesi biomarkers of serological exposure. PLoS Negl Trop Dis 2018; 12:e0006457. [PMID: 29902183 PMCID: PMC6001954 DOI: 10.1371/journal.pntd.0006457] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 04/17/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Plasmodium knowlesi is the most common cause of malaria in Malaysian Borneo, with reporting limited to clinical cases presenting to health facilities and scarce data on the true extent of transmission. Serological estimations of transmission have been used with other malaria species to garner information about epidemiological patterns. However, there are a distinct lack of suitable serosurveillance tools for this neglected disease. METHODOLOGY/PRINCIPAL FINDINGS Using in silico tools, we designed and expressed four novel P. knowlesi protein products to address the distinct lack of suitable serosurveillance tools: PkSERA3 antigens 1 and 2, PkSSP2/TRAP and PkTSERA2 antigen 1. Antibody prevalence to these antigens was determined by ELISA for three time-points post-treatment from a hospital-based clinical treatment trial in Sabah, East Malaysia (n = 97 individuals; 241 total samples for all time points). Higher responses were observed for the PkSERA3 antigen 2 (67%, 65/97) across all time-points (day 0: 36.9% 34/92; day 7: 63.8% 46/72; day 28: 58.4% 45/77) with significant differences between the clinical cases and controls (n = 55, mean plus 3 SD) (day 0 p<0.0001; day 7 p<0.0001; day 28 p<0.0001). Using boosted regression trees, we developed models to classify P. knowlesi exposure (cross-validated AUC 88.9%; IQR 86.1-91.3%) and identified the most predictive antibody responses. CONCLUSIONS/SIGNIFICANCE The PkSERA3 antigen 2 had the highest relative variable importance in all models. Further validation of these antigens is underway to determine the specificity of these tools in the context of multi-species infections at the population level.
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Affiliation(s)
- Lou S. Herman
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kimberly Fornace
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jody Phelan
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Grigg
- Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Nicholas M. Anstey
- Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
- Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
- Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia
| | - Robert W. Moon
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael J. Blackman
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Malaria Biochemistry Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Chris J. Drakeley
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Kevin K. A. Tetteh
- Department Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
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Castillo LP, Osorio A, Vargas N, Sanjuan T, Grajales A, Restrepo S. Genetic diversity of the entomopathogenic fungus Cordyceps tenuipes in forests and butterfly gardens in Quindío, Colombia. Fungal Biol 2018; 122:891-899. [PMID: 30115323 DOI: 10.1016/j.funbio.2018.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 05/16/2018] [Accepted: 05/16/2018] [Indexed: 10/16/2022]
Abstract
Cordyceps tenuipes is an entomopathogenic fungus that infects mostly pupae of several lepidopteran families. In Colombia the species has been reported in non-disturbed tropical rain forests and more recently in butterfly gardens. The aim of this study was to assess the genetic diversity in populations of C. tenuipes present in natural (forests) and artificial (e.g. butterfly gardens) environments in the department of Quindío, Colombia, using three molecular nuclear markers ITS, TEF-1α and RPB1. All the samples evaluated corresponded morphologically and phylogenetically to C. tenuipes. The butterfly garden of Quindio Botanical Garden (QBG) showed the highest genetic diversity among all sampling localities and was very similar to that of its adjacent forest. The Amaranta Butterfly Garden (ABG), located north of QBG, showed lower genetic diversity as well as little genetic differentiation with QBG, consistent with the hypothesis of a pathogen transfer from QBG to ABG. Higher FST values were observed for TEF-1α and ITS, revealing genetic differentiation between all demes and the southern forest population. Our research constitutes the first study of the intraspecific diversity of C. tenuipes in Colombia and can serve as the first step in identifying diversity reservoirs and management of epizootic episodes caused by this fungal species.
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Affiliation(s)
- Leidy P Castillo
- Departmento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
| | - Alejandro Osorio
- Departmento de Biología y Educación Ambiental, Universidad del Quindío, Armenia, Colombia
| | - Natalia Vargas
- Departmento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
| | - Tatiana Sanjuan
- Laboratorio de Taxonomía y Ecología de Hongos, Universidad de Antioquia, Calle 67 No. 53 - 108, A.A. 1226, Medellin, Colombia
| | - Alejandro Grajales
- Departmento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
| | - Silvia Restrepo
- Departmento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia.
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Muh F, Ahmed MA, Han JH, Nyunt MH, Lee SK, Lau YL, Kaneko O, Han ET. Cross-species analysis of apical asparagine-rich protein of Plasmodium vivax and Plasmodium knowlesi. Sci Rep 2018; 8:5781. [PMID: 29636493 PMCID: PMC5893618 DOI: 10.1038/s41598-018-23728-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 03/01/2018] [Indexed: 11/09/2022] Open
Abstract
The Plasmodium falciparum apical asparagine (Asn)-rich protein (AARP) is one of malarial proteins, and it has been studied as a candidate of malaria subunit vaccine. Basic characterization of PvAARP has been performed with a focus on its immunogenicity and localization. In this study, we further analyzed the immunogenicity of PvAARP, focusing on the longevity of the antibody response, cross-species immunity and invasion inhibitory activity by using the primate malaria parasite Plasmodium knowlesi. We found that vivax malaria patient sera retained anti-PvAARP antibodies for at least one year without re-infection. Recombinant PvAARP protein was strongly recognized by knowlesi malaria patients. Antibody raised against the P. vivax and P. knowlesi AARP N-termini reacted with the apical side of the P. knowlesi merozoites and inhibited erythrocyte invasion by P. knowlesi in a concentration-dependent manner, thereby suggesting a cross-species nature of anti-PvAARP antibody against PkAARP. These results can be explained by B cell epitopes predicted in conserved surface-exposed regions of the AARP N-terminus in both species. The long-lived anti-PvAARP antibody response, cross-reactivity, and invasion inhibitory activity of anti-PvAARP support a critical role of AARP during the erythrocyte invasion and suggest that PvAARP induces long-lived cross-species protective immunity against P. vivax and P. knowlesi.
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Affiliation(s)
- Fauzi Muh
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
| | - Md Atique Ahmed
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
| | - Myat Htut Nyunt
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
- Department of Medical Research, Yangon, Myanmar
| | - Seong-Kyun Lee
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea
| | - Yee Ling Lau
- Department of Parasitology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Osamu Kaneko
- Department of Protozoology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
| | - Eun-Taek Han
- Department of Medical Environmental Biology and Tropical Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do, Republic of Korea.
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Abstract
Plasmodium species cause malaria by proliferating in human erythrocytes. Invasion of immunologically privileged erythrocytes provides a relatively protective niche as well as access to a rich source of nutrients. Plasmodium spp. target erythrocytes of different ages, but share a common mechanism of invasion. Specific engagement of erythrocyte receptors defines target cell tropism, activating downstream events and resulting in the physical penetration of the erythrocyte, powered by the parasite's actinomyosin-based motor. Here we review the latest in our understanding of the molecular composition of this highly complex and fascinating biological process.
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45
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Ahmed MA, Fauzi M, Han ET. Genetic diversity and natural selection of Plasmodium knowlesi merozoite surface protein 1 paralog gene in Malaysia. Malar J 2018. [PMID: 29540177 PMCID: PMC5853062 DOI: 10.1186/s12936-018-2256-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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46
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Divis PCS, Duffy CW, Kadir KA, Singh B, Conway DJ. Genome-wide mosaicism in divergence between zoonotic malaria parasite subpopulations with separate sympatric transmission cycles. Mol Ecol 2018; 27:860-870. [PMID: 29292549 PMCID: PMC5918592 DOI: 10.1111/mec.14477] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/15/2017] [Accepted: 12/16/2017] [Indexed: 01/03/2023]
Abstract
Plasmodium knowlesi is a significant cause of human malaria transmitted as a zoonosis from macaque reservoir hosts in South‐East Asia. Microsatellite genotyping has indicated that human infections in Malaysian Borneo are an admixture of two highly divergent sympatric parasite subpopulations that are, respectively, associated with long‐tailed macaques (Cluster 1) and pig‐tailed macaques (Cluster 2). Whole‐genome sequences of clinical isolates subsequently confirmed the separate clusters, although fewer of the less common Cluster 2 type were sequenced. Here, to analyse population structure and genomic divergence in subpopulation samples of comparable depth, genome sequences were generated from 21 new clinical infections identified as Cluster 2 by microsatellite analysis, yielding a cumulative sample size for this subpopulation similar to that for Cluster 1. Profound heterogeneity in the level of intercluster divergence was distributed across the genome, with long contiguous chromosomal blocks having high or low divergence. Different mitochondrial genome clades were associated with the two major subpopulations, but limited exchange of haplotypes from one to the other was evident, as was also the case for the maternally inherited apicoplast genome. These findings indicate deep divergence of the two sympatric P. knowlesi subpopulations, with introgression likely to have occurred recently. There is no evidence yet of specific adaptation at any introgressed locus, but the recombinant mosaic types offer enhanced diversity on which selection may operate in a currently changing landscape and human environment. Loci responsible for maintaining genetic isolation of the sympatric subpopulations need to be identified in the chromosomal regions showing fixed differences.
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Affiliation(s)
- Paul C S Divis
- Faculty of Medicine and Health Sciences, Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.,Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Craig W Duffy
- Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, UK
| | - Khamisah A Kadir
- Faculty of Medicine and Health Sciences, Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - Balbir Singh
- Faculty of Medicine and Health Sciences, Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia
| | - David J Conway
- Faculty of Medicine and Health Sciences, Malaria Research Centre, Universiti Malaysia Sarawak, Kota Samarahan, Malaysia.,Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, UK
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47
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Lapp SA, Geraldo JA, Chien JT, Ay F, Pakala SB, Batugedara G, Humphrey J, DeBARRY JD, Le Roch KG, Galinski MR, Kissinger JC. PacBio assembly of a Plasmodium knowlesi genome sequence with Hi-C correction and manual annotation of the SICAvar gene family. Parasitology 2018; 145:71-84. [PMID: 28720171 PMCID: PMC5798397 DOI: 10.1017/s0031182017001329] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 06/09/2017] [Accepted: 06/20/2017] [Indexed: 12/20/2022]
Abstract
Plasmodium knowlesi has risen in importance as a zoonotic parasite that has been causing regular episodes of malaria throughout South East Asia. The P. knowlesi genome sequence generated in 2008 highlighted and confirmed many similarities and differences in Plasmodium species, including a global view of several multigene families, such as the large SICAvar multigene family encoding the variant antigens known as the schizont-infected cell agglutination proteins. However, repetitive DNA sequences are the bane of any genome project, and this and other Plasmodium genome projects have not been immune to the gaps, rearrangements and other pitfalls created by these genomic features. Today, long-read PacBio and chromatin conformation technologies are overcoming such obstacles. Here, based on the use of these technologies, we present a highly refined de novo P. knowlesi genome sequence of the Pk1(A+) clone. This sequence and annotation, referred to as the 'MaHPIC Pk genome sequence', includes manual annotation of the SICAvar gene family with 136 full-length members categorized as type I or II. This sequence provides a framework that will permit a better understanding of the SICAvar repertoire, selective pressures acting on this gene family and mechanisms of antigenic variation in this species and other pathogens.
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Affiliation(s)
- S A Lapp
- Emory Vaccine Center,Yerkes National Primate Research Center,Emory University,Atlanta, GA,USA
| | - J A Geraldo
- Federal University of Minas Gerais,Belo Horizonte, MG,Brazil
| | - J-T Chien
- Emory Vaccine Center,Yerkes National Primate Research Center,Emory University,Atlanta, GA,USA
| | - F Ay
- La Jolla Institute for Allergy and Immunology,La Jolla, CA 92037,USA
| | - S B Pakala
- Institute of Bioinformatics, University of Georgia,Athens, GA 30602,USA
| | - G Batugedara
- Center for Disease and Vector Research,Institute for Integrative Genome Biology,Department of Cell Biology & Neuroscience,University of California Riverside,CA 92521,USA
| | - J Humphrey
- Institute of Bioinformatics, University of Georgia,Athens, GA 30602,USA
| | - J D DeBARRY
- Institute of Bioinformatics, University of Georgia,Athens, GA 30602,USA
| | - K G Le Roch
- Center for Disease and Vector Research,Institute for Integrative Genome Biology,Department of Cell Biology & Neuroscience,University of California Riverside,CA 92521,USA
| | - M R Galinski
- Emory Vaccine Center,Yerkes National Primate Research Center,Emory University,Atlanta, GA,USA
| | - J C Kissinger
- Institute of Bioinformatics, University of Georgia,Athens, GA 30602,USA
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48
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Benavente ED, de Sessions PF, Moon RW, Grainger M, Holder AA, Blackman MJ, Roper C, Drakeley CJ, Pain A, Sutherland CJ, Hibberd ML, Campino S, Clark TG. A reference genome and methylome for the Plasmodium knowlesi A1-H.1 line. Int J Parasitol 2017; 48:191-196. [PMID: 29258833 DOI: 10.1016/j.ijpara.2017.09.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 08/10/2017] [Accepted: 09/26/2017] [Indexed: 10/18/2022]
Abstract
Plasmodium knowlesi, a common parasite of macaques, is recognised as a significant cause of human malaria in Malaysia. The P. knowlesi A1H1 line has been adapted to continuous culture in human erythrocytes, successfully providing an in vitro model to study the parasite. We have assembled a reference genome for the PkA1-H.1 line using PacBio long read combined with Illumina short read sequence data. Compared with the H-strain reference, the new reference has improved genome coverage and a novel description of methylation sites. The PkA1-H.1 reference will enhance the capabilities of the in vitro model to improve the understanding of P. knowlesi infection in humans.
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Affiliation(s)
- Ernest Diez Benavente
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Robert W Moon
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Munira Grainger
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Anthony A Holder
- The Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Michael J Blackman
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; The Francis Crick Institute, 1 Midland Road, London NW1 1AT, United Kingdom
| | - Cally Roper
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Christopher J Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Arnab Pain
- King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Colin J Sutherland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin L Hibberd
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; Genomics Institute Singapore, Singapore
| | - Susana Campino
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Taane G Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom; Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.
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49
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Lim C, Dankwa S, Paul AS, Duraisingh MT. Host Cell Tropism and Adaptation of Blood-Stage Malaria Parasites: Challenges for Malaria Elimination. Cold Spring Harb Perspect Med 2017; 7:a025494. [PMID: 28213436 PMCID: PMC5666624 DOI: 10.1101/cshperspect.a025494] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Plasmodium falciparum and Plasmodium vivax account for most of the mortality and morbidity associated with malaria in humans. Research and control efforts have focused on infections caused by P. falciparum and P. vivax, but have neglected other malaria parasite species that infect humans. Additionally, many related malaria parasite species infect nonhuman primates (NHPs), and have the potential for transmission to humans. For malaria elimination, the varied and specific challenges of all of these Plasmodium species will need to be considered. Recent advances in molecular genetics and genomics have increased our knowledge of the prevalence and existing diversity of the human and NHP Plasmodium species. We are beginning to identify the extent of the reservoirs of each parasite species in humans and NHPs, revealing their origins as well as potential for adaptation in humans. Here, we focus on the red blood cell stage of human infection and the host cell tropism of each human Plasmodium species. Determinants of tropism are unique among malaria parasite species, presenting a complex challenge for malaria elimination.
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Affiliation(s)
- Caeul Lim
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
| | - Selasi Dankwa
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
| | - Aditya S Paul
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115
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50
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Johri P, Krenek S, Marinov GK, Doak TG, Berendonk TU, Lynch M. Population Genomics of Paramecium Species. Mol Biol Evol 2017; 34:1194-1216. [PMID: 28204679 DOI: 10.1093/molbev/msx074] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Population-genomic analyses are essential to understanding factors shaping genomic variation and lineage-specific sequence constraints. The dearth of such analyses for unicellular eukaryotes prompted us to assess genomic variation in Paramecium, one of the most well-studied ciliate genera. The Paramecium aurelia complex consists of ∼15 morphologically indistinguishable species that diverged subsequent to two rounds of whole-genome duplications (WGDs, as long as 320 MYA) and possess extremely streamlined genomes. We examine patterns of both nuclear and mitochondrial polymorphism, by sequencing whole genomes of 10-13 worldwide isolates of each of three species belonging to the P. aurelia complex: P. tetraurelia, P. biaurelia, P. sexaurelia, as well as two outgroup species that do not share the WGDs: P. caudatum and P. multimicronucleatum. An apparent absence of global geographic population structure suggests continuous or recent dispersal of Paramecium over long distances. Intergenic regions are highly constrained relative to coding sequences, especially in P. caudatum and P. multimicronucleatum that have shorter intergenic distances. Sequence diversity and divergence are reduced up to ∼100-150 bp both upstream and downstream of genes, suggesting strong constraints imposed by the presence of densely packed regulatory modules. In addition, comparison of sequence variation at non-synonymous and synonymous sites suggests similar recent selective pressures on paralogs within and orthologs across the deeply diverging species. This study presents the first genome-wide population-genomic analysis in ciliates and provides a valuable resource for future studies in evolutionary and functional genetics in Paramecium.
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Affiliation(s)
- Parul Johri
- Department of Biology, Indiana University, Bloomington, IN
| | - Sascha Krenek
- Institute of Hydrobiology, Technische Universität Dresden, Dresden, Germany
| | | | - Thomas G Doak
- Department of Biology, Indiana University, Bloomington, IN.,National Center for Genome Analysis Support, Indiana University, Bloomington, IN
| | - Thomas U Berendonk
- Institute of Hydrobiology, Technische Universität Dresden, Dresden, Germany
| | - Michael Lynch
- Department of Biology, Indiana University, Bloomington, IN
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