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Mizushima D, Yamamoto DS, Tabbabi A, Arai M, Kato H. A rare sugar, allose, inhibits the development of Plasmodium parasites in the Anopheles mosquito independently of midgut microbiota. Front Cell Infect Microbiol 2023; 13:1162918. [PMID: 37545855 PMCID: PMC10400720 DOI: 10.3389/fcimb.2023.1162918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 06/28/2023] [Indexed: 08/08/2023] Open
Abstract
A rare sugar, allose, was reported to inhibit the development of Plasmodium parasites in Anopheles mosquitoes; however, the mechanism remains unknown. The present study addressed the inhibitory mechanism of allose on the development of the Plasmodium parasite by connecting it with bacteria involvement in the midgut. In addition, further inhibitory sugars against Plasmodium infection in mosquitoes were explored. Antibiotic-treated and antibiotic-untreated Anopheles stephensi were fed fructose with or without allose. The mosquitoes were infected with luciferase-expressing Plasmodium berghei, and parasite development was evaluated by luciferase activity. Bacterial composition analysis in gut of their mosquitoes was performed with comprehensive 16S ribosomal RNA sequencing. As the result, allose inhibited the development of oocysts in mosquitoes regardless of prior antibiotic treatment. Microbiome analysis showed that the midgut bacterial composition in mosquitoes before and after blood feeding was not affected by allose. Although allose inhibited transient growth of the midgut microbiota of mosquitoes after blood feeding, neither toxic nor inhibitory effects of allose on the dominant midgut bacteria were observed. Ookinete development in the mosquito midgut was also not affected by allose feeding. Additional 15 sugars including six monosaccharides, four polyols, and five polysaccharides were tested; however, no inhibitory effect against Plasmodium development in mosquitoes was observed. These results indicated that allose inhibits parasite development in midgut stage of the mosquito independently of midgut microbiota. Although further studies are needed, our results suggest that allose may be a useful material for the vector control of malaria as a "transmission-blocking sugar."
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Affiliation(s)
- Daiki Mizushima
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Daisuke S. Yamamoto
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Ahmed Tabbabi
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
| | - Meiji Arai
- Department of International Medical Zoology, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Hirotomo Kato
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Tochigi, Japan
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Amer NR, Lawler SP, Zohdy NM, Younes A, ElSayed WM, Connon RE. Effect of long-term exposure to copper on survival and development of two successive generations of Culex pipiens (Diptera, Culicidae). ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:351-360. [PMID: 33566271 DOI: 10.1007/s10646-021-02358-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Aquatic invertebrates can be exposed to copper from various sources, including agricultural applications. For example, concentrations up to 1000 µg L-1 are found within rice fields, where copper-containing formulations are used as fungicides and algaecides. We conducted toxicity tests to study lethal and sublethal effects of copper sulfate pentahydrate on all immature stages across two generations of Culex pipiens mosquitoes as our model organism. Mortality was dose-dependent at concentrations of 500 µg L-1 and above in the first generation, and 125 µg L-1 and above in the second generation. The median lethal concentrations (LC50) of copper sulfate pentahydrate for larval Cx. pipiens were 476 ± 30.60 µg L-1 and 348.67 ± 23.20 µg L-1 for the first and second generations, respectively. Generation one pupation decreased from 96% in controls to 48% at 500 µg L-1, while the second-generation pupation decreased from 96% in controls to 17.5% at 500 µg L-1. Mortality during the pupal stage varied from 2 to 10% at 500 µg L-1 of first and second generations, respectively. Higher levels also delayed development to adulthood in both generations. The duration of the immature period was 14.8 days in controls in both generations, but when exposed at 500 µg L-1 it increased to 18.8 days in the first generation and to 20.5 days in the second generation. The chronic, multi-generation exposures in this study showed greater toxicity than reported for shorter exposures of Cx. pipiens, and confamilial taxa like Culex hortensis and Anopheles hispaniola.
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Affiliation(s)
- Nermeen R Amer
- Department of Entomology, Faculty of Science, Cairo University, Giza, 11311, Egypt.
- Department of Entomology and Nematology, University of California, Davis, CA, 95616, USA.
| | - Sharon P Lawler
- Department of Entomology and Nematology, University of California, Davis, CA, 95616, USA
| | - Nawal M Zohdy
- Department of Entomology, Faculty of Science, Cairo University, Giza, 11311, Egypt
| | - Aly Younes
- Department of Entomology, Faculty of Science, Cairo University, Giza, 11311, Egypt
| | - Wael M ElSayed
- Department of Entomology, Faculty of Science, Cairo University, Giza, 11311, Egypt
| | - Richard E Connon
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, Davis, CA, 95616, USA
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Reza M, Ilmiawati C. Laboratory testing of low concentration (<1 ppm) of copper to prolong mosquito pupation and adult emergence time: An alternative method to delay mosquito life cycle. PLoS One 2020; 15:e0226859. [PMID: 32437348 PMCID: PMC7241823 DOI: 10.1371/journal.pone.0226859] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 05/07/2020] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Larvicide application in ovitrap is one of the currently available methods used in mosquito eradication campaign. We previously reported that copper in liquid form is a promising candidate due to its potent larvicide properties in a laboratory setting and in the field. In the field study, several larvae survived in outdoor ovitrap due to the dilution of copper concentration by rainwater. The surviving larvae were smaller and less motile. This led our interest to study the effect of a sub-lethal dose of copper in ovitrap on mosquito larval development, pupation time and lifespan in the adult stage. METHODS First instar larvae of Aedes albopictus, Anopheles stephensi, and Culex pipiens were put in water containing 0.15 ppm, 0.30 ppm, and 0.60 ppm of copper. The surviving larvae, the emerging pupae, and adult mosquitoes were observed and counted every 24-hour and statistically analyzed by t-test or Mann-Whitney U test. Inter-species difference in response to different concentration of copper were also analyzed. RESULTS Copper showed a potent larvicide effect at 0.60 ppm concentration. Prolonged pupation time and a lower number of adult mosquitoes were observed at 0.15 ppm concentration. Copper exposure did not affect adult mosquitoes' lifespan. Culex pipiens was the most susceptible species to copper exposure. CONCLUSION This study demonstrates the efficacy of copper at <1 ppm to kill mosquito larvae and to prolong pupation and adult emergence time. Utilization of copper at a low concentration is cost-efficient in the public health setting and remains an open option as an environmentally safe vector control strategy.
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Affiliation(s)
- Mohamad Reza
- Department of Biology, Faculty of Medicine, Andalas University, Padang, West Sumatra, Indonesia
- * E-mail:
| | - Cimi Ilmiawati
- Division of Environmental Toxicology, Department of Pharmacology, Faculty of Medicine, Andalas University, Padang, West Sumatra, Indonesia
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Shimada M, Hirose Y, Shimizu K, Yamamoto DS, Hayakawa EH, Matsuoka H. Upper gastrointestinal pathophysiology due to mouse malaria Plasmodium berghei ANKA infection. Trop Med Health 2019; 47:18. [PMID: 30872946 PMCID: PMC6399856 DOI: 10.1186/s41182-019-0146-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 02/20/2019] [Indexed: 12/11/2022] Open
Abstract
Background Epigastric pain, vomiting, and other gastrointestinal problems are among the most important symptoms of malaria infection as they suggest the possibility that the condition is serious. Pathophysiologies such as gastric mucosal changes and delayed gastric emptying have been reported in serious cases of malaria infection. However, it is unclear whether or not pathophysiological involvement of the upper gastrointestinal tract occurs in Plasmodium berghei ANKA (PbA)-infected mice. Methods PbA-infective Anopheles mosquitoes were used to infect mice via the natural route of infection. Fifteen PbA-C57BL/6 mice were used as a cerebral malaria model and the same numbers of PbA-BALB/c mice were used as a cerebral malaria-resistant model, and then we investigated the pathophysiological involvement of the stomach and small intestine. Results On day 8 post infection, six PbA-C57BL/6 mice showed cerebral malaria and nine others had uncomplicated infection. All the PbA-C57BL/6 mice on that same day showed severe weight loss with multiple, red gastric patches and changes to the course of the small intestine with villus goblet cell enlargement. In addition, cerebral malaria cases showed gastric gas retention with submucosal edema and small intestinal shortening. In PbA-BALB/c mice, overextension of the stomach and gas retention were evident from week 2 after PbA infection, as well as changes to the course of the small intestine and mesenteric thinning with fragility. Conclusions We described the upper gastrointestinal pathophysiology representing new findings directly linked to malarial severity and subsequent death in PbA-infected mice as a mouse model of malaria infection.
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Affiliation(s)
- Mizuho Shimada
- 1Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, 3311-1, Yakushiji, Shimotsuke City, Tochigi 329-0498 Japan
| | - Yoshie Hirose
- 2Department of Pathology, Ashikaga Red Cross Hospital, 284-1, Yobe-cho, Ashikaga City, Tochigi 326-0843 Japan
| | - Kazuhiko Shimizu
- 2Department of Pathology, Ashikaga Red Cross Hospital, 284-1, Yobe-cho, Ashikaga City, Tochigi 326-0843 Japan
| | - Daisuke S Yamamoto
- 1Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, 3311-1, Yakushiji, Shimotsuke City, Tochigi 329-0498 Japan
| | - Eri H Hayakawa
- 1Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, 3311-1, Yakushiji, Shimotsuke City, Tochigi 329-0498 Japan
| | - Hiroyuki Matsuoka
- 1Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, 3311-1, Yakushiji, Shimotsuke City, Tochigi 329-0498 Japan
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Emran TB, Iyori M, Ono Y, Amelia F, Yusuf Y, Islam A, Alam A, Tamura M, Ogawa R, Matsuoka H, Yamamoto DS, Yoshida S. Baculovirus-Induced Fast-Acting Innate Immunity Kills Liver-Stage Plasmodium. THE JOURNAL OF IMMUNOLOGY 2018; 201:2441-2451. [PMID: 30209187 DOI: 10.4049/jimmunol.1800908] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/15/2018] [Indexed: 12/14/2022]
Abstract
Baculovirus (BV), an enveloped insect virus with a circular dsDNA genome, possesses unique characteristics that induce strong innate immune responses in mammalian cells. In this study, we show that BV administration in BALB/c mice not only provides complete protection against a subsequent Plasmodium berghei sporozoite infection for up to 7 d after the injection but also eliminates existing liver-stage parasites completely. The elimination of sporozoites by BV was superior to that by primaquine, and this effect occurred in a TLR9-independent manner. At 6 h after BV administration, IFN-α and IFN-γ were robustly produced in the serum, and RNA transcripts of IFN-stimulated genes were markedly upregulated in the liver compared with control mice. The in vivo passive transfer of serum after BV administration effectively eliminated liver-stage parasites, and IFN-α neutralization abolished this effect, indicating that the BV liver-stage parasite-killing mechanism is downstream of the type I IFN signaling pathway. These findings provide evidence that BV-induced, fast-acting innate immunity completely kills liver-stage parasites and, thus, may lead to new malaria drug and vaccine strategies.
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Affiliation(s)
- Talha Bin Emran
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Mitsuhiro Iyori
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Yuki Ono
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Fitri Amelia
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Yenni Yusuf
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Ashekul Islam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Asrar Alam
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Megumi Tamura
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Ryohei Ogawa
- Department of Radiological Sciences, University of Toyama, Toyama 930-0194, Japan; and
| | - Hiroyuki Matsuoka
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0431, Japan
| | - Daisuke S Yamamoto
- Division of Medical Zoology, Department of Infection and Immunity, Jichi Medical University, Shimotsuke 329-0431, Japan
| | - Shigeto Yoshida
- Laboratory of Vaccinology and Applied Immunology, Kanazawa University School of Pharmacy, Kakuma-machi, Kanazawa 920-1192, Japan;
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Emran TB, Iyori M, Ono Y, Amelia F, Yusuf Y, Islam A, Alam A, Ogawa R, Matsuoka H, Yamamoto D, Yoshida S. Baculovirus-inducing fast-acting innate immunity kills Plasmodium liver stages.. [DOI: 10.1101/320036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
ABSTRACTBaculovirus (BV), an enveloped insect virus with a circular double-stranded DNA genome, possesses unique characteristics that induce strong innate immune responses in mammalian cells. Here, we show that BV administration not only sterilely protects BALB/c mice for at least 7 days from subsequent Plasmodium berghei sporozoite infection but also eliminates existing liver-stage parasites completely, effects superior to those of primaquine, and does so in a TLR9-independent manner. Six hours post-BV administration, IFN-α and IFN-γ were robustly produced in serum, and RNA transcripts of interferon-stimulated genes were drastically upregulated in the liver. The in vivo passive transfer of post-BV administration serum effectively eliminated liver-stage parasites, and IFN-α neutralization abolished this effect, indicating that the BV liver-stage parasite killing mechanism is downstream of the type I IFN signaling pathway. Our results demonstrate that BV is a potent IFN-inducing prophylactic and therapeutic agent with great potential for further development as a new malaria vaccine and/or anti-hypnozoite drug.
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Tavares J, Costa DM, Teixeira AR, Cordeiro-da-Silva A, Amino R. In vivo imaging of pathogen homing to the host tissues. Methods 2017; 127:37-44. [PMID: 28522323 DOI: 10.1016/j.ymeth.2017.05.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/19/2017] [Accepted: 05/10/2017] [Indexed: 12/19/2022] Open
Abstract
Hematogenous dissemination followed by tissue tropism is a characteristic of the infectious process of many pathogens including those transmitted by blood-feeding vectors. After entering into the blood circulation, these pathogens must arrest in the target organ before they infect a specific tissue. Here, we describe a non-invasive method to visualize and quantify the homing of pathogens to the host tissues. By using in vivo bioluminescence imaging we quantify the accumulation of luciferase-expressing parasites in the host organs during the first minutes following their intravascular inoculation in mice. Using this technique we show that in the malarial infection, once in the blood circulation, most of bioluminescent Plasmodium berghei sporozoites, the parasite stage transmitted to the host skin by a mosquito bite, rapidly home to the liver where they invade and develop inside hepatocytes. This homing is specific to this developmental stage since blood stage parasites do not accumulate in the liver, as well as extracellular Trypanosoma brucei bloodstream forms and liver-infecting Leishmania infantum amastigotes. Finally, this method can be used to study the dynamics of tissue tropism of parasites, dissect the molecular and cellular basis of their increased arrest in organs and to evaluate immune interventions designed to block this targeted interaction.
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Affiliation(s)
- Joana Tavares
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.
| | - David Mendes Costa
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Ana Rafaela Teixeira
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Anabela Cordeiro-da-Silva
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal; IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal; Faculdade de Farmácia da Universidade do Porto, Departamento de Ciências Biológicas, Portugal
| | - Rogerio Amino
- Unit of Malaria Infection and Immunity, Institut Pasteur, Paris, France.
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Mezzanotte L, van 't Root M, Karatas H, Goun EA, Löwik CWGM. In Vivo Molecular Bioluminescence Imaging: New Tools and Applications. Trends Biotechnol 2017; 35:640-652. [PMID: 28501458 DOI: 10.1016/j.tibtech.2017.03.012] [Citation(s) in RCA: 199] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 03/07/2017] [Accepted: 03/27/2017] [Indexed: 12/19/2022]
Abstract
in vivo bioluminescence imaging (BLi) is an optical molecular imaging technique used to visualize molecular and cellular processes in health and diseases and to follow the fate of cells with high sensitivity using luciferase-based gene reporters. The high sensitivity of this technique arises from efficient photon production, followed by the reaction between luciferase enzymes and luciferin substrates. Novel discoveries and developments of luciferase reporters, substrates, and gene-editing techniques, and emerging fields of applications, promise a new era of deeper and more sensitive molecular imaging.
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Affiliation(s)
- Laura Mezzanotte
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands.
| | - Moniek van 't Root
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
| | - Hacer Karatas
- Laboratory of Bioorganic Chemistry and Molecular Imaging, Institute of Chemical Sciences and Engineering (ISIC), Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Elena A Goun
- Laboratory of Bioorganic Chemistry and Molecular Imaging, Institute of Chemical Sciences and Engineering (ISIC), Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Clemens W G M Löwik
- Optical Molecular imaging, Department of Radiology, Erasmus MC, Rotterdam, The Netherlands
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Salivary Gland Proteome during Adult Development and after Blood Feeding of Female Anopheles dissidens Mosquitoes (Diptera: Culicidae). PLoS One 2016; 11:e0163810. [PMID: 27669021 PMCID: PMC5036837 DOI: 10.1371/journal.pone.0163810] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 09/14/2016] [Indexed: 12/28/2022] Open
Abstract
Understanding changes in mosquito salivary proteins during the time that sporozoite maturation occurs and after blood feeding may give information regarding the roles of salivary proteins during the malarial transmission. Anopheles dissidens (formerly Anopheles barbirostris species A1) is a potential vector of Plasmodium vivax in Thailand. In this study, analyses of the proteomic profiles of female An. dissidens salivary glands during adult development and after blood feeding were carried out using two-dimensional gel electrophoresis coupled with nano-liquid chromatography-mass spectrometry. Results showed at least 17 major salivary gland proteins present from day one to day 21 post emergence at 8 different time points sampled. Although there was variation observed, the patterns of protein expression could be placed into one of four groups. Fifteen protein spots showed significant depletion after blood feeding with the percentages of the amount of depletion ranging from 8.5% to 68.11%. The overall results identified various proteins, including a putative mucin-like protein, an anti-platelet protein, a long form D7 salivary protein, a putative gVAG protein precursor, a D7-related 3.2 protein, gSG7 salivary proteins, and a gSG6 protein. These results allow better understanding of the changes of the salivary proteins during the adult mosquito development. They also provide candidate proteins to investigate any possible link or not between sporozoite maturation, or survival of skin stage sporozoites, and salivary proteins.
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De Niz M, Stanway RR, Wacker R, Keller D, Heussler VT. An ultrasensitive NanoLuc-based luminescence system for monitoring Plasmodium berghei throughout its life cycle. Malar J 2016; 15:232. [PMID: 27102897 PMCID: PMC4840902 DOI: 10.1186/s12936-016-1291-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 04/13/2016] [Indexed: 01/08/2023] Open
Abstract
Background Bioluminescence imaging is widely used for cell-based assays and animal imaging studies, both in biomedical research and drug development. Its main advantages include its high-throughput applicability, affordability, high sensitivity, operational simplicity, and quantitative outputs. In malaria research, bioluminescence has been used for drug discovery in vivo and in vitro, exploring host-pathogen interactions, and studying multiple aspects of Plasmodium biology. While the number of fluorescent proteins available for imaging has undergone a great expansion over the last two decades, enabling simultaneous visualization of multiple molecular and cellular events, expansion of available luciferases has lagged behind. The most widely used bioluminescent probe in malaria research is the Photinus pyralis firefly luciferase, followed by the more recently introduced Click-beetle and Renilla luciferases. Ultra-sensitive imaging of Plasmodium at low parasite densities has not been previously achieved. With the purpose of overcoming these challenges, a Plasmodium berghei line expressing the novel ultra-bright luciferase enzyme NanoLuc, called PbNLuc has been generated, and is presented in this work. Results NanoLuc shows at least 150 times brighter signal than firefly luciferase in vitro, allowing single parasite detection in mosquito, liver, and sexual and asexual blood stages. As a proof-of-concept, the PbNLuc parasites were used to image parasite development in the mosquito, liver and blood stages of infection, and to specifically explore parasite liver stage egress, and pre-patency period in vivo. Conclusions PbNLuc is a suitable parasite line for sensitive imaging of the entire Plasmodium life cycle. Its sensitivity makes it a promising line to be used as a reference for drug candidate testing, as well as the characterization of mutant parasites to explore the function of parasite proteins, host-parasite interactions, and the better understanding of Plasmodium biology. Since the substrate requirements of NanoLuc are different from those of firefly luciferase, dual bioluminescence imaging for the simultaneous characterization of two lines, or two separate biological processes, is possible, as demonstrated in this work.
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Affiliation(s)
- Mariana De Niz
- Institute of Cell Biology, University of Bern, 3012, Bern, Switzerland.
| | - Rebecca R Stanway
- Institute of Cell Biology, University of Bern, 3012, Bern, Switzerland
| | - Rahel Wacker
- Institute of Cell Biology, University of Bern, 3012, Bern, Switzerland
| | - Derya Keller
- Institute of Cell Biology, University of Bern, 3012, Bern, Switzerland
| | - Volker T Heussler
- Institute of Cell Biology, University of Bern, 3012, Bern, Switzerland
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