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Nature Immunology Sep 2023Malaria is caused by Plasmodium species transmitted by Anopheles mosquitoes. Following a mosquito bite, Plasmodium sporozoites migrate from skin to liver, where...
Malaria is caused by Plasmodium species transmitted by Anopheles mosquitoes. Following a mosquito bite, Plasmodium sporozoites migrate from skin to liver, where extensive replication occurs, emerging later as merozoites that can infect red blood cells and cause symptoms of disease. As liver tissue-resident memory T cells (Trm cells) have recently been shown to control liver-stage infections, we embarked on a messenger RNA (mRNA)-based vaccine strategy to induce liver Trm cells to prevent malaria. Although a standard mRNA vaccine was unable to generate liver Trm or protect against challenge with Plasmodium berghei sporozoites in mice, addition of an agonist that recruits T cell help from type I natural killer T cells under mRNA-vaccination conditions resulted in significant generation of liver Trm cells and effective protection. Moreover, whereas previous exposure of mice to blood-stage infection impaired traditional vaccines based on attenuated sporozoites, mRNA vaccination was unaffected, underlining the potential for such a rational mRNA-based strategy in malaria-endemic regions.
Topics: Animals; Mice; Memory T Cells; Malaria; Liver; Malaria Vaccines; Plasmodium berghei; CD8-Positive T-Lymphocytes
PubMed: 37474653
DOI: 10.1038/s41590-023-01562-6 -
Cell Host & Microbe Feb 2023Malaria transmission to mosquitoes requires a developmental switch in asexually dividing blood-stage parasites to sexual reproduction. In Plasmodium berghei, the...
Malaria transmission to mosquitoes requires a developmental switch in asexually dividing blood-stage parasites to sexual reproduction. In Plasmodium berghei, the transcription factor AP2-G is required and sufficient for this switch, but how a particular sex is determined in a haploid parasite remains unknown. Using a global screen of barcoded mutants, we here identify genes essential for the formation of either male or female sexual forms and validate their importance for transmission. High-resolution single-cell transcriptomics of ten mutant parasites portrays the developmental bifurcation and reveals a regulatory cascade of putative gene functions in the determination and subsequent differentiation of each sex. A male-determining gene with a LOTUS/OST-HTH domain as well as the protein interactors of a female-determining zinc-finger protein indicate that germ-granule-like ribonucleoprotein complexes complement transcriptional processes in the regulation of both male and female development of a malaria parasite.
Topics: Animals; Female; Male; Parasites; Malaria; Plasmodium berghei; Sexual Development; Culicidae; Protozoan Proteins
PubMed: 36634679
DOI: 10.1016/j.chom.2022.12.011 -
Science (New York, N.Y.) Aug 2019Malaria parasites adopt a remarkable variety of morphological life stages as they transition through multiple mammalian host and mosquito vector environments. We...
Malaria parasites adopt a remarkable variety of morphological life stages as they transition through multiple mammalian host and mosquito vector environments. We profiled the single-cell transcriptomes of thousands of individual parasites, deriving the first high-resolution transcriptional atlas of the entire life cycle. We then used our atlas to precisely define developmental stages of single cells from three different human malaria parasite species, including parasites isolated directly from infected individuals. The Malaria Cell Atlas provides both a comprehensive view of gene usage in a eukaryotic parasite and an open-access reference dataset for the study of malaria parasites.
Topics: Animals; Anopheles; Atlases as Topic; Genes, Protozoan; HeLa Cells; Humans; Life Cycle Stages; Malaria; Plasmodium berghei; Single-Cell Analysis; Transcriptome
PubMed: 31439762
DOI: 10.1126/science.aaw2619 -
Cell Reports Nov 2023Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized...
Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized subcellular compartments to extensively remodel the host cell for its survival. The information to fully understand these compartments is likely hidden in the so far poorly characterized Plasmodium species spatial proteome. To address this question, we determined the steady-state subcellular location of more than 12,000 parasite proteins across five different species by extensive subcellular fractionation of erythrocytes infected by Plasmodium falciparum, Plasmodium knowlesi, Plasmodium yoelii, Plasmodium berghei, and Plasmodium chabaudi. This comparison of the pan-species spatial proteomes and their expression patterns indicates increasing species-specific proteins associated with the more external compartments, supporting host adaptations and post-transcriptional regulation. The spatial proteome offers comprehensive insight into the different human, simian, and rodent Plasmodium species, establishing a powerful resource for understanding species-specific host adaptation processes in the parasite.
Topics: Humans; Proteomics; Malaria; Proteome; Plasmodium berghei; Erythrocytes
PubMed: 37952150
DOI: 10.1016/j.celrep.2023.113419 -
Journal of Visualized Experiments : JoVE May 2023Malaria is a deadly disease caused by the parasite Plasmodium and is transmitted through the bite of female Anopheles mosquitoes. The sporozoite stage of Plasmodium...
Malaria is a deadly disease caused by the parasite Plasmodium and is transmitted through the bite of female Anopheles mosquitoes. The sporozoite stage of Plasmodium deposited by mosquitoes in the skin of vertebrate hosts undergoes a phase of mandatory development in the liver before initiating clinical malaria. We know little about the biology of Plasmodium development in the liver; access to the sporozoite stage and the ability to genetically modify such sporozoites are critical tools for studying the nature of Plasmodium infection and the resulting immune response in the liver. Here, we present a comprehensive protocol for the generation of transgenic Plasmodium berghei sporozoites. We genetically modify blood-stage P. berghei and use this form to infect Anopheles mosquitoes when they take a blood meal. After the transgenic parasites undergo development in the mosquitoes, we isolate the sporozoite stage of the parasite from the mosquito salivary glands for in vivo and in vitro experimentation. We demonstrate the validity of the protocol by generating sporozoites of a novel strain of P. berghei expressing the green fluorescent protein (GFP) subunit 11 (GFP11), and show how it could be used to investigate the biology of liver-stage malaria.
Topics: Animals; Female; Sporozoites; Plasmodium berghei; Animals, Genetically Modified; Anopheles; Malaria
PubMed: 37212590
DOI: 10.3791/64992 -
Current Drug Discovery Technologies 2022Turmeric (Curcuma longa L.) is a popular spice containing curcumin that is responsible for its therapeutic effects. Curcumin with anti-inflammatory, antioxidant,... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Turmeric (Curcuma longa L.) is a popular spice containing curcumin that is responsible for its therapeutic effects. Curcumin with anti-inflammatory, antioxidant, anti-cancer, and antimicrobial activities has led to a lot of research focusing on it over the years. This systematic review aimed to evaluate research on the anti-Plasmodium berghei activity of curcumin and its derivatives.
METHODS
Our study was performed according to PRISMA guidelines and was recorded in the database of a systematic review and preclinical meta-analysis of CAMARADESNC3Rs (SyRF). The search was performed in five databases, namely Scopus, PubMed, Web of Science, EMBASE, and Google Scholar, from 2010 to 2020. The following keywords were searched: "Plasmodium berghei", "Medicinal Plants", "Curcumin", "Concentration", Animals kind", "Treatment Durations", "Routes of Administration" and "in vivo".
RESULTS
Of the 3,500 papers initially obtained, 14 articles were reliable and were thus scrutinized. Animal models were included in all studies. The most commonly used animal strain was Albino (43%), followed by C57BL/6 (22%). The other studies used various murine strains, including BALB/c (14%) and ICR (7%). Two (14%) studies did not mention the strain of animal model used. Curcumin alone or in combination with other compounds depending on the dose used, route of administration, and animal model showed a moderate to strong anti-Plasmodium berghei effect.
CONCLUSION
According to the studies, curcumin has anti-malarial effects on Plasmodium berghei, and, however, its effect on human Plasmodium is unclear. Due to the side effects and drug resistance of current drugs in the treatment of human malaria, the use of new compounds with few or no side effects, such as curcumin, is recommended as an alternative or complementary treatment.
Topics: Animals; Anti-Inflammatory Agents; Antimalarials; Curcumin; Malaria; Mice; Plasmodium berghei
PubMed: 35293297
DOI: 10.2174/1570163819666220315140736 -
Annual Review of Microbiology Sep 2022The malaria parasite life cycle alternates between two hosts: a vertebrate and the female mosquito vector. Cell division, proliferation, and invasion are essential for... (Review)
Review
The malaria parasite life cycle alternates between two hosts: a vertebrate and the female mosquito vector. Cell division, proliferation, and invasion are essential for parasite development, transmission, and survival. Most research has focused on development in the vertebrate, which causes disease; however, knowledge of malaria parasite development in the mosquito (the sexual and transmission stages) is now rapidly accumulating, gathered largely through investigation of the rodent malaria model, with In this review, we discuss the seminal genome-wide screens that have uncovered key regulators of cell proliferation, invasion, and transmission during sexual development. Our focus is on the roles of transcription factors, reversible protein phosphorylation, and molecular motors. We also emphasize the still-unanswered important questions around key pathways in cell division during the vector transmission stages and how they may be targeted in future studies.
Topics: Animals; Anopheles; Female; Malaria; Mosquito Vectors; Parasites; Plasmodium berghei
PubMed: 35609946
DOI: 10.1146/annurev-micro-041320-010046 -
Frontiers in Cellular and Infection... 2023Malaria is one of the leading health problems globally. Plasmodium infection causes pronounced sexual dimorphism, and the lethality and severity are more remarkable in...
INTRODUCTION
Malaria is one of the leading health problems globally. Plasmodium infection causes pronounced sexual dimorphism, and the lethality and severity are more remarkable in males than in females. To study the role of testosterone in the susceptibility and mortality of males in malaria, it is common to increase its concentration. However, this strategy does not consider the enzyme CYP19A1 aromatase, which can transform it into oestrogens.
METHODS
To avoid the interference of oestrogens, we inhibited in vivo CYP19A1 aromatase with letrozole and increased the testosterone level by exogen administration before infection with Plasmodium berghei ANKA. We measured the impact on free testosterone, 17β-oestradiol and dehydroepiandrosterone levels in plasma; additionally, we evaluated parasitaemia, body temperature, body mass, glucose levels and haemoglobin concentration. Furthermore, we evaluated the effects of testosterone on the immune response; we quantified the CD3+/CD4+, CD3+/CD8+, CD19+, Mac-3+ and NK cells in the spleen and the plasma concentrations of the cytokines IL-2, IL-4, IL-6, IFN-, IL-10, TNF-α and IL-17A. Finally, we quantified the levels of antibodies.
RESULTS
We found that mice treated with the combination of letrozole and testosterone and infected with Plasmodium berghei ANKA had increased concentrations of free testosterone and DHEA but decreased levels of 17β-oestradiol. As a result, parasitaemia increased, leading to severe anaemia. Interestingly, testosterone increased temperature and decreased glucose concentration as a possible testosterone-mediated regulatory mechanism. The severity of symptomatology was related to critical immunomodulatory effects generated by free testosterone; it selectively increased CD3+CD8+ T and CD19+ cells but decreased Mac-3+. Remarkably, it reduced IL-17A concentration and increased IL-4 and TNF-α. Finally, it increased IgG1 levels and the IgG1/IgG2a ratio. In conclusion, free testosterone plays an essential role in pathogenesis in male mice by increasing CD8+ and decreasing Mac3+ cells and mainly reducing IL-17A levels, which is critical in the development of anaemia. Our results are important for understanding the mechanisms that regulate the exacerbated inflammatory response in infectious diseases and would be useful for the future development of alternative therapies to reduce the mortality generated by inflammatory processes.
Topics: Male; Female; Animals; Mice; Testosterone; Letrozole; Aromatase; Interleukin-17; Plasmodium berghei; Interleukin-4; Tumor Necrosis Factor-alpha; Immunoglobulin G; Estradiol; Estrogens; Immunity
PubMed: 37384220
DOI: 10.3389/fcimb.2023.1146356 -
Nature Communications Sep 2023The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities...
The Aurora family of kinases orchestrates chromosome segregation and cytokinesis during cell division, with precise spatiotemporal regulation of its catalytic activities by distinct protein scaffolds. Plasmodium spp., the causative agents of malaria, are unicellular eukaryotes with three unique and highly divergent aurora-related kinases (ARK1-3) that are essential for asexual cellular proliferation but lack most canonical scaffolds/activators. Here we investigate the role of ARK2 during sexual proliferation of the rodent malaria Plasmodium berghei, using a combination of super-resolution microscopy, mass spectrometry, and live-cell fluorescence imaging. We find that ARK2 is primarily located at spindle microtubules in the vicinity of kinetochores during both mitosis and meiosis. Interactomic and co-localisation studies reveal several putative ARK2-associated interactors including the microtubule-interacting protein EB1, together with MISFIT and Myosin-K, but no conserved eukaryotic scaffold proteins. Gene function studies indicate that ARK2 and EB1 are complementary in driving endomitotic division and thereby parasite transmission through the mosquito. This discovery underlines the flexibility of molecular networks to rewire and drive unconventional mechanisms of chromosome segregation in the malaria parasite.
Topics: Animals; Chromosome Segregation; Cell Nucleus Division; Plasmodium berghei; Cell Proliferation; Meiosis; Aurora Kinases; Eukaryota
PubMed: 37704606
DOI: 10.1038/s41467-023-41395-3 -
Parasites & Vectors Jul 2022Malaria is a major global parasitic disease caused by species of the genus Plasmodium. Zygotes of Plasmodium spp. undergo meiosis and develop into tetraploid ookinetes,...
BACKGROUND
Malaria is a major global parasitic disease caused by species of the genus Plasmodium. Zygotes of Plasmodium spp. undergo meiosis and develop into tetraploid ookinetes, which differentiate into oocysts that undergo sporogony. Homologous recombination (HR) occurs during meiosis and introduces genetic variation. However, the mechanisms of HR in Plasmodium are unclear. In humans, the recombinases DNA repair protein Rad51 homolog 1 (Rad51) and DNA meiotic recombinase 1 (Dmc1) are required for HR and are regulated by breast cancer susceptibility protein 2 (BRCA2). Most eukaryotes harbor BRCA2 homologs. Nevertheless, these have not been reported for Plasmodium.
METHODS
A Brca2 candidate was salvaged from a database to identify Brca2 homologs in Plasmodium. To confirm that the candidate protein was Brca2, interaction activity between Plasmodium berghei (Pb) Brca2 (PbBrca2) and Rad51 (PbRad51) was investigated using a mammalian two-hybrid assay. To elucidate the functions of PbBrca2, PbBrca2 was knocked out and parasite proliferation and differentiation were assessed in mice and mosquitoes. Transmission electron microscopy was used to identify sporogony.
RESULTS
The candidate protein was conserved among Plasmodium species, and it was indicated that it harbors critical BRCA2 domains including BRC repeats, tower, and oligonucleotide/oligosaccharide-binding-fold domains. The P. berghei BRC repeats interacted with PbRad51. Hence, the candidate was considered a Brca2 homolog. PbBrca2 knockout parasites were associated with reduced parasitemia with increased ring stage and decreased trophozoite stage counts, gametocytemia, female gametocyte ratio, oocyst number, and ookinete development in both mice and mosquitoes. Nevertheless, the morphology of the blood stages in mice and the ookinete stage was comparable to those of the wild type parasites. Transmission electron microscopy results showed that sporogony never progressed in Brca2-knockout parasites.
CONCLUSIONS
Brca2 is implicated in nearly all Plasmodium life cycle stages, and especially in sporogony. PbBrca2 contributes to HR during meiosis.
Topics: Animals; Culicidae; Female; Homologous Recombination; Life Cycle Stages; Malaria; Mammals; Mice; Oocysts; Parasites; Plasmodium berghei
PubMed: 35804459
DOI: 10.1186/s13071-022-05357-w