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Sasaki H, Sekiguchi H, Sugiyama M, Ikadai H. Plasmodium berghei Cap93, a novel oocyst capsule-associated protein, plays a role in sporozoite development. Parasit Vectors 2017; 10:399. [PMID: 28841886 PMCID: PMC5574095 DOI: 10.1186/s13071-017-2337-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 08/16/2017] [Indexed: 11/20/2022] Open
Affiliation(s)
- Hanae Sasaki
- Hokusan Co. Ltd., 27-4, Kitanosato, Kitahiroshima, Hokkaido, 061-111, Japan
| | - Harumi Sekiguchi
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Makoto Sugiyama
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan
| | - Hiromi Ikadai
- Laboratory of Veterinary Parasitology, School of Veterinary Medicine, Kitasato University, Towada, Aomori, 034-8628, Japan.
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2
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Abstract
Protective immunity against preerythrocytic malaria parasite infection is difficult to achieve. Intracellular Plasmodium parasites likely minimize antigen presentation by surface-expressed major histocompatibility complex class I (MHC-I) molecules on infected cells, yet they actively remodel their host cells by export of parasite factors. Whether exported liver-stage proteins constitute better candidates for MHC-I antigen presentation to CD8+ T lymphocytes remains unknown. Here, we systematically characterized the contribution of protein export to the magnitude of antigen-specific T-cell responses against Plasmodium berghei liver-stage parasites in C57BL/6 mice. We generated transgenic sporozoites that secrete a truncated ovalbumin (OVA) surrogate antigen only in the presence of an amino-terminal protein export element. Immunization with live attenuated transgenic sporozoites revealed that antigen export was not critical for CD8+ T-cell priming but enhanced CD8+ T-cell proliferation in the liver. Upon transfer of antigen-specific CD8+ T cells, liver-stage parasites secreting the target protein were eliminated more efficiently. We conclude that Plasmodium parasites strictly control protein export during liver infection to minimize immune recognition. Strategies that enhance the discharge of parasite proteins into infected hepatocytes could improve the efficacy of candidate preerythrocytic malaria vaccines. Vaccine development against Plasmodium parasites remains a priority in malaria research. The most advanced malaria subunit vaccine candidates contain Plasmodium surface proteins with important roles for parasite vital functions. A fundamental question is whether recognition by effector CD8+ T cells is restricted to sporozoite surface antigens or extends to parasite proteins that are synthesized during the extensive parasite expansion phase in the liver. Using a surrogate model antigen, we found that a cytoplasmic antigen is able to induce robust protective CD8+ T-cell responses, but protein export further enhances immunogenicity and protection. Our results show that a cytoplasmic localization does not exclude a protein’s candidacy for malaria subunit vaccines and that protein secretion can enhance protective immunity.
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3
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Sinden RE, Blagborough AM, Churcher T, Ramakrishnan C, Biswas S, Delves MJ. The design and interpretation of laboratory assays measuring mosquito transmission of Plasmodium. Trends Parasitol 2012; 28:457-65. [DOI: 10.1016/j.pt.2012.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 07/20/2012] [Accepted: 07/24/2012] [Indexed: 12/14/2022]
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4
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Matuschewski K. Getting infectious: formation and maturation of Plasmodium sporozoites in the Anopheles vector. Cell Microbiol 2006; 8:1547-56. [PMID: 16984410 DOI: 10.1111/j.1462-5822.2006.00778.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Research on Plasmodium sporozoite biology aims at understanding the developmental program steering the formation of mature infectious sporozoites - the transmission stage of the malaria parasite. The recent identification of genes that are vital for sporozoite egress from oocysts and subsequent targeting and transmigration of the mosquito salivary glands allows the identification of mosquito factors required for life cycle completion. Mature sporozoites appear to be equipped with the entire molecular repertoire for successful transmission and subsequent initiation of liver stage development. Innovative malaria intervention strategies that target the early, non-pathogenic phases of the life cycle will crucially depend on our insights into sporozoite biology and the underlying molecular mechanisms that lead the parasite from the mosquito midgut to the liver.
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Affiliation(s)
- Kai Matuschewski
- Department of Parasitology, Heidelberg University School of Medicine, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
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5
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Carvalho TG, Thiberge S, Sakamoto H, Ménard R. Conditional mutagenesis using site-specific recombination in Plasmodium berghei. Proc Natl Acad Sci U S A 2004; 101:14931-6. [PMID: 15465918 PMCID: PMC522007 DOI: 10.1073/pnas.0404416101] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2004] [Indexed: 01/14/2023] Open
Abstract
Reverse genetics in Plasmodium, the genus of parasites that cause malaria, still faces major limitations. Only red blood cell stages of this haploid parasite can be transfected. Consequently, the function of many essential genes in these and subsequent stages, including those encoding vaccine candidates, cannot be addressed genetically. Here, we establish conditional mutagenesis in Plasmodium by using site-specific recombination and the Flp/FRT system of yeast. Site-specific recombination is induced after cross-fertilization in the mosquito vector of two clones containing either the target sequence flanked by two FRT sites or the Flp recombinase. Parasites that have undergone recombination are recognized in the cross progeny through the expression of a fluorescence marker. This approach should permit to dissect the function of any essential gene of Plasmodium during the haploid phase of its life, i.e., during infection of salivary glands in the mosquito and infection of both the liver and red blood cells in the mammal.
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Affiliation(s)
- Teresa Gil Carvalho
- Unité de Biologie et Génétique du Paludisme, Institut Pasteur, 25 Rue du Docteur Roux, 75724 Paris Cedex 15, France
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6
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Sidén-Kiamos I, Vlachou D, Margos G, Beetsma A, Waters AP, Sinden RE, Louis C. Distinct roles for pbs21 and pbs25 in the in vitro ookinete to oocyst transformation of Plasmodium berghei. J Cell Sci 2000; 113 Pt 19:3419-26. [PMID: 10984433 DOI: 10.1242/jcs.113.19.3419] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have developed an in vitro culture system for early sporogonic stages of Plasmodium berghei, which can be used to study developmental events normally taking place in the midgut of an infected mosquito. These include penetration of insect cells by the mature ookinete, transformation into oocysts and the early development of the latter, sustained through several rounds of nuclear division. The system, based upon co-culture of enriched ookinetes with several established insect cell lines, was used to study the development of mutant ookinetes lacking both the Pbs21 and Pbs25 surface proteins. Motility and entry of double knockout and Pbs21 single knockout ookinetes into the insect cells are normal, but the number of ookinetes successfully transforming into oocysts expressing the CSP protein are substantially reduced. Finally, using the yeast two-hybrid system we also show that Pbs25 has the capacity to homodimerise as well as to form heterodimers with Pbs21.
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Affiliation(s)
- I Sidén-Kiamos
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Crete, Greece
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7
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Gonzalez-Ceron L, Rodriguez MH, Wirtz RA, Sina BJ, Palomeque OL, Nettel JA, Tsutsumi V. Plasmodium vivax: a monoclonal antibody recognizes a circumsporozoite protein precursor on the sporozoite surface. Exp Parasitol 1998; 90:203-11. [PMID: 9806864 DOI: 10.1006/expr.1998.4334] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The major surface circumsporozoite (CS) proteins are known to play a role in malaria sporozoite development and invasion of invertebrate and vertebrate host cells. Plasmodium vivax CS protein processing during mosquito midgut oocyst and salivary gland sporozoite development was studied using monoclonal antibodies which recognize different CS protein epitopes. Monoclonal antibodies which react with the CS amino acid repeat sequences by ELISA recognized a 50-kDa precursor protein in immature oocyst and additional 47- and 42-kDa proteins in older oocysts. A 42-kDa CS protein was detected after initial sporozoite invasion of mosquito salivary glands and an additional 50-kDa precursor CS protein observed later in infected salivary glands. These data confirm previous results with other Plasmodium species, in which more CS protein precursors were detected in oocysts than in salivary gland sporozoites. A monoclonal antibody (PvPCS) was characterized which reacts with an epitope found only in the 50-kDa precursor CS protein. PvPCS reacted with all P. vivax sporozoite strains tested by indirect immunofluorescent assay, homogeneously staining the sporozoite periphery with much lower intensity than that produced by anti-CS repeat antibodies. Immunoelectron microscopy using PvPCS showed that the CS protein precursor was associated with peripheral cytoplasmic vacuoles and membranes of sporoblast and budding sporozoites in development oocysts. In salivary gland sporozoites, the CS protein precursor was primarily associated with micronemes and sporozoite membranes. Our results suggest that the 50-kDa CS protein precursor is synthesized intracellularly and secreted on the membrane surface, where it is proteolytically processed to form the 42-kDa mature CS protein. These data indicate that differences in CS protein processing in oocyst and salivary gland sporozoites development may occur.
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MESH Headings
- Animals
- Anopheles/parasitology
- Antibodies, Monoclonal/immunology
- Antibodies, Protozoan/immunology
- Antibody Specificity
- Antigens, Protozoan/analysis
- Antigens, Protozoan/immunology
- Antigens, Surface/analysis
- Antigens, Surface/immunology
- Enzyme-Linked Immunosorbent Assay
- Epitopes/immunology
- Female
- Fluorescent Antibody Technique, Indirect
- Humans
- Hybridomas
- Immunoblotting
- Insect Vectors/parasitology
- Malaria, Vivax/blood
- Malaria, Vivax/parasitology
- Mice
- Microscopy, Immunoelectron
- Plasmodium vivax/immunology
- Plasmodium vivax/ultrastructure
- Protein Precursors/analysis
- Protein Precursors/immunology
- Protozoan Proteins/analysis
- Protozoan Proteins/immunology
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Affiliation(s)
- L Gonzalez-Ceron
- Centro de Investigación de Paludismo, Instituto Nacional de Salud Pública, 4 Norte and 19 Poniente, Tapachula, Chiapas, 30700, Mexico
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8
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Ménard R, Sultan AA, Cortes C, Altszuler R, van Dijk MR, Janse CJ, Waters AP, Nussenzweig RS, Nussenzweig V. Circumsporozoite protein is required for development of malaria sporozoites in mosquitoes. Nature 1997; 385:336-40. [PMID: 9002517 DOI: 10.1038/385336a0] [Citation(s) in RCA: 229] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Malaria parasites undergo a sporogonic cycle in the mosquito vector. Sporozoites, the form of the parasite injected into the host during a bloodmeal, develop inside oocysts in the insect midgut, then migrate to and eventually invade the salivary glands. The circumsporozoite protein (CS), one of the major proteins synthesized by salivary gland sporozoites, is a surface-associated molecule which is important in sporozoite infectivity to the host. Here, by gene targeting, we created Plasmodium berghei lines in which the single-copy CS gene was disrupted. The CS(-) and wild-type parasites produced similar numbers of oocysts of comparable size in the mosquito midgut. In the CS(-) oocysts, however, sporozoite formation was profoundly inhibited. CS therefore appears to have a pleiotropic role and to be vital for malaria parasites in both the vector and the host: in mosquitoes, CS is essential for sporozoite development within oocysts, and in the vertebrate host it promotes sporozoite attachment to hepatocytes.
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Affiliation(s)
- R Ménard
- Michael Heidelberger Division of Immunology, Department of Pathology, Kaplan Cancer Center, New York University Medical Center, 10016, USA.
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9
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Abstract
The purpose of this review is to summarize the biology of Plasmodium in the mosquito including recent data to contribute to better understanding of the developmental interaction between mosquito and malarial parasite. The entire sporogonic cycle is discussed taking into consideration different parasite/vector interactions and factors affecting parasite development to the mosquito.
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Affiliation(s)
- A B Simonetti
- Departamento de Microbiologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brasil.
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10
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Simonetti AB, Billingsley PF, Winger LA, Sinden RE. Kinetics of expression of two major Plasmodium berghei antigens in the mosquito vector, Anopheles stephensi. J Eukaryot Microbiol 1993; 40:569-76. [PMID: 8401470 DOI: 10.1111/j.1550-7408.1993.tb06109.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Expression of a 21 kDa determinant (Pbs21), first detected on the surface of ookinetes, and of the circumsporozoite protein (CSP) was studied by immunofluorescence and Western blots during the developmental cycle of Plasmodium berghei in the mosquito Anopheles stephensi. The expression of Pbs21 was predominantly localised on the ookinete surface one day after the infectious blood meal, and thereafter reactivity declined to a minimum on days 2 and 3, the time of onset of oocyst development. A gradual increase in fluorescence was observed on the oocysts from day 6 that was retained until day 17 post-infection. In contrast, sporozoites released from oocysts or salivary glands showed little or no antibody labelling with anti-Pbs21. Circumsporozoite protein was not detectable in any midgut preparations until 5-6 days after feeding, when reactivity was observed against immature oocysts. Expression then continued and increased throughout oocyst and sporozoite development. Western blots confirmed that Pbs21 was expressed minimally during the oocyst development but was not detectable in sporozoites. Co-localisation of anti-Pbs21 and anti-CSP monoclonal antibodies to the 50 kDa and 60 kDa bands in Western blots of sporozoite suggests immunological cross-reactivity between the CSP and the anti-21 kDa antibodies.
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Affiliation(s)
- A B Simonetti
- Department of Biology, Imperial College of Science, Technology and Medicine, London, United Kingdom
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11
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Abstract
A basic fact in malariology is that human malaria infections result from the bite of an infective anopheline mosquito. Without sporozoite transmission there is no malaria. Here, John Beier highlights our understanding of sporozoite biology from the perspective of how sporozoites develop and survive in mosquitoes, how they are transmitted during bloodfeeding, and how key elements in sporozoite-vector relationships present new opportunities for tackling critical questions relevant for disease control.
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Affiliation(s)
- J C Beier
- Department of Immunology and Infectious Diseases, School of Hygiene and Public Health, The Johns Hopkins University, 615 North Wolfe Street, Baltimore, MD 21205, USA
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12
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Warburg A, Touray M, Krettli AU, Miller LH. Plasmodium gallinaceum: antibodies to circumsporozoite protein prevent sporozoites from invading the salivary glands of Aedes aegypti. Exp Parasitol 1992; 75:303-7. [PMID: 1426132 DOI: 10.1016/0014-4894(92)90215-v] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A circumsporozoite protein-specific monoclonal antibody (N2H6D5) was injected into malaria-infected mosquitoes to determine its effect on the sporogonic cycle. After injection of antibody into mosquitoes (100 ng each), positive immunofluorescence (measured on air-dried sporozoites) reactions in hemolymph extracts were observed at a dilution of 1:1000. At 72 hr postinjection the levels dropped to 1:10. Sporozoites coinjected with antibody did not invade the salivary glands. In naturally infected mosquitoes, sporozoites were released over a period of 3 to 4 days. Therefore, mosquitoes were injected twice. The first injection was a day before the beginning of sporozoite release and the second, 2 days later. Sporozoite invasion of the salivary glands was assessed 3 days after the second injection, by microscopic examination of dissected glands. At this stage, all oocysts had completed maturation and released the sporozoites. Salivary gland infections were totally prevented in mosquitoes given two injections of 100 ng N2H6D5. Hence, sustained presence of anti-circumsporozoite antibodies in the hemolymph can render female Aedes aegypti refractory to Plasmodium gallinaceum.
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Affiliation(s)
- A Warburg
- Laboratory of Malaria Research, National Institute of Allergy & Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
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13
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Beier JC, Vaughan JA, Madani A, Noden BH. Plasmodium falciparum: release of circumsporozoite protein by sporozoites in the mosquito vector. Exp Parasitol 1992; 75:248-56. [PMID: 1516673 DOI: 10.1016/0014-4894(92)90185-d] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The release of circumsporozoite (CS) protein by Plasmodium falciparum sporozoites was investigated to identify factors regulating this process within infected Anopheles gambiae mosquitoes. The potential for sporozoites to release CS protein in vitro was not dependent upon their site-specific developmental stage (i.e., mature oocysts, hemolymph, salivary glands), their duration in the vector, or their exposure to mosquito-derived components such as salivary glands or hemolymph. The capacity of sporozoites to release CS protein was depressed by mosquito blood feeding during periods of sporozoite migration to the salivary glands, but the effect was only temporary and those sporozoites already in the glands were not affected. Free CS protein in the salivary glands was present in 93.3% of 45 infective mosquitoes. Sporozoites from these same, individual mosquitoes were also tested in vitro for CS protein release. In both cases, the amount of soluble CS protein increased as a function of sporozoite density but the total amount of CS protein per sporozoite became progressively less with increasing numbers of sporozoites. Further experiments showed that sporozoite contact with increasing amounts of soluble CS protein caused a down-regulation of CS protein release. Thus, a primary factor regulating the production and release of CS protein by sporozoites is their contact with soluble CS protein within the mosquito.
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Affiliation(s)
- J C Beier
- Department of Immunology and Infectious Diseases, Johns Hopkins University, School of Hygiene and Public Health, Baltimore, Maryland 21205
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14
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Rudin W, Petignat C, Tanner M, Matile H. Distribution of repetitive and non-repetitive circumsporozoite protein epitopes on Plasmodium falciparum sporozoites and immunochemical characterization of human malaria antisera. Acta Trop 1992; 51:257-70. [PMID: 1279961 DOI: 10.1016/0001-706x(92)90044-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The presence and distribution of circumsporozoite protein (CSP) epitopes located in the repetitive and non-repetitive regions were studied in three Plasmodium falciparum strains, NF54, IFA5 and IFA6. It was found by immunofluorescence, Western blotting and immunoelectron microscopy that mAbs to epitopes of the repetitive domaine bound similarly to the CSP of all three strains. MAbs to epitopes of the flanking regions yielded either some strain differences (mAbs to the C-terminal end), or reacted only in immunofluorescence tests on whole sporozoites (mAbs to the N-terminal end). Human sera from an area endemic for malaria, two of them positive in ELISA on (NANP)40 and two negative, were tested for their reactivity with epitopes of the flanking regions of the CSP. The presence of antibodies to such epitopes could be demonstrated by Western blots and immunocytochemistry independent of the reactivity of the sera to recognize (NANP)40. All tested bound to salivary gland tissues but not to their secretory product in immunocytochemical experiments.
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Affiliation(s)
- W Rudin
- Swiss Tropical Institute, Basel
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15
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Meis JF, Croes H, Mons B, van Belkum A, Ponnudurai T. Localization of circumsporozoite protein in the sporogonic stages of Plasmodium vivax. Parasitol Res 1992; 78:165-7. [PMID: 1557329 DOI: 10.1007/bf00931660] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- J F Meis
- Department of Parasitology, University Hospital Nijmegen, The Netherlands
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16
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Stewart MJ, Vanderberg JP. Malaria sporozoites release circumsporozoite protein from their apical end and translocate it along their surface. THE JOURNAL OF PROTOZOOLOGY 1991; 38:411-21. [PMID: 1787427 DOI: 10.1111/j.1550-7408.1991.tb01379.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Plasmodium sporozoites, the causative agents of malaria, release circumsporozoite (CS) protein into medium when under conditions simulating those that the parasites encounter in the bloodstream of the vertebrate host. CS protein of the rodent parasite, Plasmodium berghei, is released as the lower molecular weight form, Pb44. This release is substratum- and antibody-independent. Previous studies show that CS protein is released at the trailing, posterior end of motile sporozoites. Video and electron microscopic studies now demonstrate that CS protein is released at the apical end of cytochalasin b-immobilized sporozoites. We propose that CS protein released from the apical end, the leading end of gliding sporozoites, adheres to the sporozoite surface and is translocated posteriorly by a cytochalasin-sensitive and apparently actin-mediated surface motor, which drives gliding motility. This model explains the mechanism of both the circumsporozoite precipitation (CSP) reaction and formation of the CS protein trail by gliding sporozoites.
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Affiliation(s)
- M J Stewart
- Department of Medical and Molecular Parasitology, New York University School of Medicine, NY 10016
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17
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Affiliation(s)
- M Aikawa
- Institute of Pathology, Case Western Reserve University, Cleveland, Ohio 44106
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18
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Hamilton AJ, Bartholomew MA, Hay RJ. Immunogold electron microscopical detection of tubulin and actin within mycelial phase Histoplasma capsulatum capsulatum and H. capsulatum duboisii. Mycoses 1989; 32:405-10. [PMID: 2797056 DOI: 10.1111/j.1439-0507.1989.tb02271.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Immunogold electron microscopy using LR Gold as a resin was undertaken to determine the distribution of actin and tubulin within the hyphae of Histoplasma capsulatum capsulatum and H. capsulatum duboisii. Both of these proteins were found throughout the cytoplasm when probed with the appropriate monoclonal antibodies.
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Abstract
This review represents a highly personal view of only some of the advances made on the biology of malaria in the period 1986-1987. Progress has stemmed largely from new or refined techniques applied to the logical demonstration of eukaryotic principles; and more rarely from either new conceptual advances, or the revelation of critical differences in the biology of Plasmodium from that of other eukaryotes. Significant steps have been made in the recognition of the complexity of interaction between the parasite and both its vertebrate and invertebrate hosts. It is this very complexity of interaction which warns against the presumption that the successful application of any single control strategy is imminent.
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Affiliation(s)
- R E Sinden
- Department of Pure and Applied Biology, Imperial College, London, UK
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