Novel mutations in K13 propeller gene of artemisinin-resistant Plasmodium falciparum.
Ontology highlight
ABSTRACT:
SUBMITTER: Isozumi R
PROVIDER: S-EPMC4344268 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The emergence of artemisinin resistance in Southeast Asia imperils efforts to reduce the global malaria burden. We genetically modified the Plasmodium falciparum K13 locus using zinc-finger nucleases and measured ring-stage survival rates after drug exposure in vitro; these rates correlate with parasite clearance half-lives in artemisinin-treated patients. With isolates from Cambodia, where resistance first emerged, survival rates decreased from 13 to 49% to 0.3 to 2.4% after the removal of K13 mutations. Conversely, survival rates in wild-type parasites increased from ≤0.6% to 2 to 29% after the insertion of K13 mutations. These mutations conferred elevated resistance to recent Cambodian isolates compared with that of reference lines, suggesting a contemporary contribution of additional genetic factors. Our data provide a conclusive rationale for worldwide K13-propeller sequencing to identify and eliminate artemisinin-resistant parasites.
| S-EPMC4349400 | biostudies-literature
Project description:BACKGROUND: Bangladesh is a malaria hypo-endemic country sharing borders with India and Myanmar. Artemisinin combination therapy (ACT) remains successful in Bangladesh. An increase of artemisinin-resistant malaria parasites on the Thai-Cambodia and Thai-Myanmar borders is worrisome. K13 propeller gene (PF3D7_1343700 or PF13_0238) mutations have been linked to both in vitro artemisinin resistance and in vivo slow parasite clearance rates. This group undertook to evaluate if mutations seen in Cambodia have emerged in Bangladesh where ACT use is now standard for a decade. METHODS: Samples were obtained from Plasmodium falciparum-infected malaria patients from Upazila health complexes (UHC) between 2009 and 2013 in seven endemic districts of Bangladesh. These districts included Khagrachari (Matiranga UHC), Rangamati (Rajasthali UHC), Cox's Bazar (Ramu and Ukhia UHC), Bandarban (Lama UHC), Mymensingh (Haluaghat UHC), Netrokona (Durgapur and Kalmakanda UHC), and Moulvibazar (Sreemangal and Kamalganj UHC). RESULTS: Out of 296 microscopically positive P. falciparum samples, 271 (91.6%) were confirmed as mono-infections by both real-time PCR and nested PCR. The K13 propeller gene from 253 (93.4%) samples was sequenced bi-directionally. One non-synonymous mutation (A578S) was found in Bangladeshi clinical isolates. The A578S mutation was confirmed and lies adjacent to the C580Y mutation, the major mutation causing delayed parasite clearance in Cambodia. Based on computational modeling A578S should have a significant effect on tertiary structure of the protein. CONCLUSION: The data suggest that P. falciparum in Bangladesh remains free of the C580Y mutation linked to delayed parasite clearance. However, the mutation A578S is present and based on structural analysis could affect K13 gene function. Further in vivo clinical studies are required to validate the effect of this mutation.
| S-EPMC4240861 | biostudies-literature
Project description:IntroductionArtemisinin-based combination therapies (ACTs) act as first-line antimalarial drugs and play a crucial role in the successful control of falciparum malaria. However, the recent emergence of resistance of Plasmodium falciparum to ACTs in South East Asia is of particular concern. Hence, there is an urgent need to identify the genetic determinants of and understand the molecular mechanisms underpinning such resistance. Artemisinin resistance (AR) is primarily driven by the mutations in the P. falciparum K13 protein, which is widely recognized as the major molecular marker of AR. However, association of K13 mutations with in vivo AR has been ambiguous due to the absence of a tractable model.MethodsIn this study, we have successfully produced artemisinin- and piperaquine-resistant P. berghei K173 following drug administrations. Prolonged parasite clearance and early recrudescence were found following daily exposure to high doses of artemisinin and piperaquine. We have also sequenced the DNA of artemisinin-resistant strains and piperaquine-resistant strains of P. berghei K173 to explore the relationship between PfK13 and AR.ResultsThe resistance index of P. berghei K173 reached 12.4 after 30 artemisinin-resistant generations, but AR declined gradually after 30 generations. On the 50th generation, the resistance index of artemisinin-resistant strains was only 5.0 compared with the severe drug resistance of piperaquine-resistant strains (I90=148.8). DNA sequencing of artemisinin-resistant strains showed that there were 9 meaningful mutations at P. berghei K13-propeller domain, but the above mutations did not include common clinical point mutations.ConclusionOur data show that artemisinin is less susceptible to severe resistance compared with other antimalarial drugs. In addition, mutation on P. berghei K13 has a multi-drug-resistant phenotype and may be used as a biomarker to monitor its resistance. More studies need to be conducted on the new mutations detected so as to understand their association, if any, with ACT resistance.
| S-EPMC9653030 | biostudies-literature
Project description:Artemisinin-based combination therapies (ACTs) have been recommended by the World Health Organization (WHO) as first-line treatment of uncomplicated Plasmodium falciparum (P. falciparum) malaria since 2005 in Democratic Republic of Congo (DRC) and a regular surveillance of the ACT efficacy is required to ensure the treatment effectiveness. Mutations in the propeller domain of the pfk13 gene were identified as molecular markers of artemisinin resistance (ART-R). This study investigated the pfk13-propeller gene polymorphism in clinical isolates of P. falciparum collected in the DRC. In 2017, ten geographical sites across DRC were selected for a cross-sectional study that was conducted first in Kinshasa from January to March, then in the nine other sites from September to December. Dried blood samples were collected from patients attending health centers for fever where diagnosis of Malaria was first made by rapid diagnostic test (RDT) available on site (SD Bioline malaria Ag Pf or CareStart Malaria Pf) or by thick blood smear and then confirmed by a P. falciparum real-time PCR assay. A pfk13-propeller segment containing a fragment that codes for amino acids at positions 427-595 was amplified by conventional PCR before sequencing. In total, 1070 patients were enrolled in the study. Real-time PCR performed confirmed the initial diagnosis of P. falciparum infection in 806 samples (75.3%; 95% CI: 72.6%- 77.9%). Of the 717 successfully sequenced P. falciparum isolates, 710 (99.0%; 95% CI: 97.9% - 99.6) were wild-type genotypes and 7 (1.0%; 95% CI: 0.4% - 2.1%) carried non-synonymous (NS) mutations in pfk13-propeller including 2 mutations (A578S and V534A) previously detected and 2 other (M472I and A569T) not yet detected in the DRC. Mutations associated with ART-R in Southeast Asia were not observed in DRC. However, the presence of other mutations in pfk13-propeller gene calls for further investigations to assess their implication in drug resistance.
| S-EPMC7446852 | biostudies-literature
Project description:Artemisinin-resistant Plasmodium falciparum malaria has been documented in southeast Asia and may already be spreading in that region. Molecular markers are important tools for monitoring the spread of antimalarial drug resistance. Recently, single-nucleotide polymorphisms (SNPs) in the PF3D7_1343700 kelch propeller (K13-propeller) domain were shown to be associated with artemisinin resistance in vivo and in vitro. The prevalence and role of K13-propeller mutations are poorly known in sub-Saharan Africa. K13-propeller mutations were genotyped by direct sequencing of nested polymerase chain reaction (PCR) amplicons from dried blood spots of pre-treatment falciparum malaria infections collected before and after the use of artemisinin-based combination therapy (ACT) as first-line therapy in Mali. Although K13-propeller mutations previously associated with delayed parasite clearance in Cambodia were not identified, 26 K13-propeller mutations were identified in both recent samples and pre-ACT infections. Parasite clearance time was comparable between infections with non-synonymous K13-propeller mutations and infections with the reference allele. These findings suggest that K13-propeller mutations are present in artemisinin-sensitive parasites and that they preceded the wide use of ACTs in Mali.
| S-EPMC4458826 | biostudies-literature
Project description:Antimalarial drugs are a key tool in malaria elimination programs. With the emergence of artemisinin resistance in southeast Asia, an effort to identify molecular markers for surveillance of resistant malaria parasites is underway. Non-synonymous mutations in the kelch propeller domain (K13-propeller) in Plasmodium falciparum have been associated with artemisinin resistance in samples from southeast Asia, but additional studies are needed to characterize this locus in other P. falciparum populations with different levels of artemisinin use. Here, we sequenced the K13-propeller locus in 82 samples from Haiti, where limited government oversight of non-governmental organizations may have resulted in low-level use of artemisinin-based combination therapies. We detected a single-nucleotide polymorphism (SNP) at nucleotide 1,359 in a single isolate. Our results contribute to our understanding of the global genomic diversity of the K13-propeller locus in P. falciparum populations.
| S-EPMC4350547 | biostudies-literature
Project description:Recent gains in reducing the global burden of malaria are threatened by the emergence of Plasmodium falciparum resistance to artemisinins. The discovery that mutations in portions of a P. falciparum gene encoding kelch (K13)-propeller domains are the major determinant of resistance has provided opportunities for monitoring such resistance on a global scale.We analyzed the K13-propeller sequence polymorphism in 14,037 samples collected in 59 countries in which malaria is endemic. Most of the samples (84.5%) were obtained from patients who were treated at sentinel sites used for nationwide surveillance of antimalarial resistance. We evaluated the emergence and dissemination of mutations by haplotyping neighboring loci.We identified 108 nonsynonymous K13 mutations, which showed marked geographic disparity in their frequency and distribution. In Asia, 36.5% of the K13 mutations were distributed within two areas--one in Cambodia, Vietnam, and Laos and the other in western Thailand, Myanmar, and China--with no overlap. In Africa, we observed a broad array of rare nonsynonymous mutations that were not associated with delayed parasite clearance. The gene-edited Dd2 transgenic line with the A578S mutation, which expresses the most frequently observed African allele, was found to be susceptible to artemisinin in vitro on a ring-stage survival assay.No evidence of artemisinin resistance was found outside Southeast Asia and China, where resistance-associated K13 mutations were confined. The common African A578S allele was not associated with clinical or in vitro resistance to artemisinin, and many African mutations appear to be neutral. (Funded by Institut Pasteur Paris and others.).
| S-EPMC4955562 | biostudies-literature
Project description:The emergence of mutant K13-mediated artemisinin (ART) resistance in Plasmodium falciparum malaria parasites has led to widespread treatment failures across Southeast Asia. In Africa, K13-propeller genotyping confirms the emergence of the R561H mutation in Rwanda and highlights the continuing dominance of wild-type K13 elsewhere. Using gene editing, we show that R561H, along with C580Y and M579I, confer elevated in vitro ART resistance in some African strains, contrasting with minimal changes in ART susceptibility in others. C580Y and M579I cause substantial fitness costs, which may slow their dissemination in high-transmission settings, in contrast with R561H that in African 3D7 parasites is fitness neutral. In Cambodia, K13 genotyping highlights the increasing spatio-temporal dominance of C580Y. Editing multiple K13 mutations into a panel of Southeast Asian strains reveals that only the R561H variant yields ART resistance comparable to C580Y. In Asian Dd2 parasites C580Y shows no fitness cost, in contrast with most other K13 mutations tested, including R561H. Editing of point mutations in ferredoxin or mdr2, earlier associated with resistance, has no impact on ART susceptibility or parasite fitness. These data underline the complex interplay between K13 mutations, parasite survival, growth and genetic background in contributing to the spread of ART resistance.
| S-EPMC8321553 | biostudies-literature
Project description:Molecular markers associated with artemisinin resistance in Plasmodium falciparum are yet to be well defined. Recent studies showed that polymorphisms in K13 gene are associated with artemisinin resistance. The present study was designed to know the pattern of polymorphisms in propeller region of K13 gene among the clinical isolates collected from urban Kolkata after five years of ACT implementation. We collected 59 clinical isolates from urban Kolkata and sequenced propeller region of K13 gene in 51 isolates successfully. We did not find any mutation in any isolate. All patients responded to the ACT, a combination of artesunate + sulphadoxine-pyrimethamine. The drug regimen is still effective in the study area and there is no sign of emergence of resistance against artemisinin as evidenced by wild genotype of K13 gene in all isolates studied.
| S-EPMC4673352 | biostudies-literature
Project description:Mutations in the Plasmodium falciparum K13-propeller domain have recently been shown to be important determinants of artemisinin resistance in Southeast Asia. This study investigated the prevalence of K13-propeller polymorphisms across sub-Saharan Africa. A total of 1212 P. falciparum samples collected from 12 countries were sequenced. None of the K13-propeller mutations previously reported in Southeast Asia were found, but 22 unique mutations were detected, of which 7 were nonsynonymous. Allele frequencies ranged between 1% and 3%. Three mutations were observed in >1 country, and the A578S was present in parasites from 5 countries. This study provides the baseline prevalence of K13-propeller mutations in sub-Saharan Africa.
| S-EPMC4827505 | biostudies-literature