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Kolářová I, Valigurová A. Hide-and-Seek: A Game Played between Parasitic Protists and Their Hosts. Microorganisms 2021; 9:2434. [PMID: 34946036 PMCID: PMC8707157 DOI: 10.3390/microorganisms9122434] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/17/2021] [Accepted: 11/20/2021] [Indexed: 11/17/2022] Open
Abstract
After invading the host organism, a battle occurs between the parasitic protists and the host's immune system, the result of which determines not only whether and how well the host survives and recovers, but also the fate of the parasite itself. The exact weaponry of this battle depends, among others, on the parasite localisation. While some parasitic protists do not invade the host cell at all (extracellular parasites), others have developed successful intracellular lifestyles (intracellular parasites) or attack only the surface of the host cell (epicellular parasites). Epicellular and intracellular protist parasites have developed various mechanisms to hijack host cell functions to escape cellular defences and immune responses, and, finally, to gain access to host nutrients. They use various evasion tactics to secure the tight contact with the host cell and the direct nutrient supply. This review focuses on the adaptations and evasion strategies of parasitic protists on the example of two very successful parasites of medical significance, Cryptosporidium and Leishmania, while discussing different localisation (epicellular vs. intracellular) with respect to the host cell.
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Affiliation(s)
- Iva Kolářová
- Laboratory of Vector Biology, Department of Parasitology, Faculty of Science, Charles University, Albertov 6, 128 44 Prague, Czech Republic
| | - Andrea Valigurová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
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Nutrient Acquisition and Attachment Strategies in Basal Lineages: A Tough Nut to Crack in the Evolutionary Puzzle of Apicomplexa. Microorganisms 2021; 9:microorganisms9071430. [PMID: 34361866 PMCID: PMC8303630 DOI: 10.3390/microorganisms9071430] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/28/2021] [Accepted: 06/28/2021] [Indexed: 01/22/2023] Open
Abstract
Apicomplexa are unicellular eukaryotes that parasitise a wide spectrum of invertebrates and vertebrates, including humans. In their hosts, they occupy a variety of niches, from extracellular cavities (intestine, coelom) to epicellular and intracellular locations, depending on the species and/or developmental stages. During their evolution, Apicomplexa thus developed an exceptionally wide range of unique features to reach these diversified parasitic niches and to survive there, at least long enough to ensure their own transmission or that of their progeny. This review summarises the current state of knowledge on the attachment/invasive and nutrient uptake strategies displayed by apicomplexan parasites, focusing on trophozoite stages of their so far poorly studied basal representatives, which mostly parasitise invertebrate hosts. We describe their most important morphofunctional features, and where applicable, discuss existing major similarities and/or differences in the corresponding mechanisms, incomparably better described at the molecular level in the more advanced Apicomplexa species, of medical and veterinary significance, which mainly occupy intracellular niches in vertebrate hosts.
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Boisard J, Florent I. Why the -omic future of Apicomplexa should include gregarines. Biol Cell 2020; 112:173-185. [PMID: 32176937 DOI: 10.1111/boc.202000006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 03/03/2020] [Accepted: 03/10/2020] [Indexed: 12/15/2022]
Abstract
Gregarines, a polyphyletic group of apicomplexan parasites infecting mostly non-vertebrates hosts, remains poorly known at taxonomic, phylogenetic and genomic levels. However, it represents an essential group for understanding evolutionary history and adaptive capacities of apicomplexan parasites to the remarkable diversity of their hosts. Because they have a mostly extracellular lifestyle, gregarines have developed other cellular developmental forms and host-parasite interactions, compared with their much better studied apicomplexan cousins, intracellular parasites of vertebrates (Hemosporidia, Coccidia, Cryptosporidia). This review highlights the promises offered by the molecular exploration of gregarines, that have been until now left on the side of the road of the comparative -omic exploration of apicomplexan parasites. Elucidating molecular bases for both their ultrastructural, functional and behavioural similarities and differences, compared with those of the typical apicomplexan models, is expected to provide entirely novel clues on the adaptive capacities developed by Apicomplexa over evolution. A challenge remains to identify which gregarines should be explored in priority, as recent metadata from open and host-associated environments have confirmed how underestimated is our current view on true gregarine biodiversity. It is now time to turn to gregarines to widen the currently highly skewed view we have of adaptive mechanisms developed by Apicomplexa.
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Affiliation(s)
- Julie Boisard
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245), Département Adaptations du Vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, Paris, Cedex 05, France.,Structure et instabilité des génomes (STRING UMR 7196 CNRS / INSERM U1154), Département Adaptations du Vivant (AVIV), Muséum National d'Histoire Naturelle, Paris, Cedex 05, France
| | - Isabelle Florent
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245), Département Adaptations du Vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, Paris, Cedex 05, France
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Valigurova A, Peckova R, Dolezal K, Sak B, Kvetonova D, Kvac M, Nurcahyo W, Foitova I. Limitations in the screening of potentially anti-cryptosporidial agents using laboratory rodents with gastric cryptosporidiosis. Folia Parasitol (Praha) 2018; 65. [PMID: 30152784 DOI: 10.14411/fp.2018.010] [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: 09/19/2017] [Accepted: 05/31/2018] [Indexed: 11/19/2022]
Abstract
The emergence of cryptosporidiosis, a zoonotic disease of the gastrointestinal and respiratory tract caused by Cryptosporidium Tyzzer, 1907, triggered numerous screening studies of various compounds for potential anti-cryptosporidial activity, the majority of which proved ineffective. Extracts of Indonesian plants, Piper betle and Diospyros sumatrana, were tested for potential anti-cryptosporidial activity using Mastomys coucha (Smith), experimentally inoculated with Cryptosporidium proliferans Kváč, Havrdová, Hlásková, Daňková, Kanděra, Ježková, Vítovec, Sak, Ortega, Xiao, Modrý, Chelladurai, Prantlová et McEvoy, 2016. None of the plant extracts tested showed significant activity against cryptosporidia; however, the results indicate that the following issues should be addressed in similar experimental studies. The monitoring of oocyst shedding during the entire experimental trial, supplemented with histological examination of affected gastric tissue at the time of treatment termination, revealed that similar studies are generally unreliable if evaluations of drug efficacy are based exclusively on oocyst shedding. Moreover, the reduction of oocyst shedding did not guarantee the eradication of cryptosporidia in treated individuals. For treatment trials performed on experimentally inoculated laboratory rodents, only animals in the advanced phase of cryptosporidiosis should be used for the correct interpretation of pathological alterations observed in affected tissue. All the solvents used (methanol, methanol-tetrahydrofuran and dimethylsulfoxid) were shown to be suitable for these studies, i.e. they did not exhibit negative effects on the subjects. The halofuginone lactate, routinely administered in intestinal cryptosporidiosis in calves, was shown to be ineffective against gastric cryptosporidiosis in mice caused by C. proliferans. In contrast, the control application of extract Arabidopsis thaliana, from which we had expected a neutral effect, turned out to have some positive impact on affected gastric tissue.
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Affiliation(s)
- Andrea Valigurova
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Radka Peckova
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Karel Dolezal
- Department of Chemical Biology and Genetics & Laboratory of Growth Regulators, Centre of the Region Hana for Biotechnological and Agricultural Research, Faculty of Science, Palacky University, and Institute of Experimental Botany, Academy of Sciences of Czech Republic, Olomouc-Holice, Czech Republic
| | - Bohumil Sak
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Dana Kvetonova
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Martin Kvac
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic.,Department of Animal Husbandry Sciences, Faculty of Agriculture, University of South Bohemia in Ceske Budejovice, Czech Republic
| | - Wisnu Nurcahyo
- Department of Parasitology, Faculty of Veterinary Medicine, Gadjah Mada University, Yogyakarta, Indonesia
| | - Ivona Foitova
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Brno, Czech Republic.,Department of Parasitology, Faculty of Veterinary Medicine, Gadjah Mada University, Yogyakarta, Indonesia
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Simdyanov TG, Guillou L, Diakin AY, Mikhailov KV, Schrével J, Aleoshin VV. A new view on the morphology and phylogeny of eugregarines suggested by the evidence from the gregarine Ancora sagittata (Leuckart, 1860) Labbé, 1899 (Apicomplexa: Eugregarinida). PeerJ 2017; 5:e3354. [PMID: 28584702 PMCID: PMC5452951 DOI: 10.7717/peerj.3354] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 04/26/2017] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Gregarines are a group of early branching Apicomplexa parasitizing invertebrate animals. Despite their wide distribution and relevance to the understanding the phylogenesis of apicomplexans, gregarines remain understudied: light microscopy data are insufficient for classification, and electron microscopy and molecular data are fragmentary and overlap only partially. METHODS Scanning and transmission electron microscopy, PCR, DNA cloning and sequencing (Sanger and NGS), molecular phylogenetic analyses using ribosomal RNA genes (18S (SSU), 5.8S, and 28S (LSU) ribosomal DNAs (rDNAs)). RESULTS AND DISCUSSION We present the results of an ultrastructural and molecular phylogenetic study on the marine gregarine Ancora sagittata from the polychaete Capitella capitata followed by evolutionary and taxonomic synthesis of the morphological and molecular phylogenetic evidence on eugregarines. The ultrastructure of Ancora sagittata generally corresponds to that of other eugregarines, but reveals some differences in epicytic folds (crests) and attachment apparatus to gregarines in the family Lecudinidae, where Ancora sagittata has been classified. Molecular phylogenetic trees based on SSU (18S) rDNA reveal several robust clades (superfamilies) of eugregarines, including Ancoroidea superfam. nov., which comprises two families (Ancoridae fam. nov. and Polyplicariidae) and branches separately from the Lecudinidae; thus, all representatives of Ancoroidea are here officially removed from the Lecudinidae. Analysis of sequence data also points to possible cryptic species within Ancora sagittata and the inclusion of numerous environmental sequences from anoxic habitats within the Ancoroidea. LSU (28S) rDNA phylogenies, unlike the analysis of SSU rDNA alone, recover a well-supported monophyly of the gregarines involved (eugregarines), although this conclusion is currently limited by sparse taxon sampling and the presence of fast-evolving sequences in some species. Comparative morphological analyses of gregarine teguments and attachment organelles lead us to revise their terminology. The terms "longitudinal folds" and "mucron" are restricted to archigregarines, whereas the terms "epicystic crests" and "epimerite" are proposed to describe the candidate synapomorphies of eugregarines, which, consequently, are considered as a monophyletic group. Abolishing the suborders Aseptata and Septata, incorporating neogregarines into the Eugregarinida, and treating the major molecular phylogenetic lineages of eugregarines as superfamilies appear as the best way of reconciling recent morphological and molecular evidence. Accordingly, the diagnosis of the order Eugregarinida Léger, 1900 is updated.
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Affiliation(s)
- Timur G. Simdyanov
- Faculty of Biology, Department of Invertebrate Zoology, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Laure Guillou
- UMR 7144, Laboratoire Adaptation et Diversité en Milieu Marin, CNRS, Paris, Roscoff, France
- UMR 7144, Station Biologique de Roscoff, CNRS, Sorbonne Universités, Université Pierre et Marie Curie - Paris 6, Paris, Roscoff, France
| | - Andrei Y. Diakin
- Faculty of Science, Department of Botany and Zoology, Masaryk University, Brno, Czech Republic
| | - Kirill V. Mikhailov
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
- Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
| | - Joseph Schrével
- CNRS 7245, Molécules de Communication et Adaptation of Micro-organisms, Paris, France
- Muséum National d’Histoire Naturelle, UMR 7245, Sorbonne Universités, Paris, France
| | - Vladimir V. Aleoshin
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
- Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russian Federation
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Kváč M, Havrdová N, Hlásková L, Daňková T, Kanděra J, Ježková J, Vítovec J, Sak B, Ortega Y, Xiao L, Modrý D, Chelladurai JRJJ, Prantlová V, McEvoy J. Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae): Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals. PLoS One 2016; 11:e0147090. [PMID: 26771460 PMCID: PMC4714919 DOI: 10.1371/journal.pone.0147090] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 12/26/2015] [Indexed: 11/23/2022] Open
Abstract
The morphological, biological, and molecular characteristics of Cryptosporidium muris strain TS03 are described, and the species name Cryptosporidium proliferans n. sp. is proposed. Cryptosporidium proliferans obtained from a naturally infected East African mole rat (Tachyoryctes splendens) in Kenya was propagated under laboratory conditions in rodents (SCID mice and southern multimammate mice, Mastomys coucha) and used in experiments to examine oocyst morphology and transmission. DNA from the propagated C. proliferans isolate, and C. proliferans DNA isolated from the feces of an African buffalo (Syncerus caffer) in Central African Republic, a donkey (Equus africanus) in Algeria, and a domestic horse (Equus caballus) in the Czech Republic were used for phylogenetic analyses. Oocysts of C. proliferans are morphologically distinguishable from C. parvum and C. muris HZ206, measuring 6.8–8.8 (mean = 7.7 μm) × 4.8–6.2 μm (mean = 5.3) with a length to width ratio of 1.48 (n = 100). Experimental studies using an isolate originated from T. splendens have shown that the course of C. proliferans infection in rodent hosts differs from that of C. muris and C. andersoni. The prepatent period of 18–21 days post infection (DPI) for C. proliferans in southern multimammate mice (Mastomys coucha) was similar to that of C. andersoni and longer than the 6–8 DPI prepatent period for C. muris RN66 and HZ206 in the same host. Histopatologicaly, stomach glands of southern multimammate mice infected with C. proliferans were markedly dilated and filled with necrotic material, mucus, and numerous Cryptosporidium developmental stages. Epithelial cells of infected glands were atrophic, exhibited cuboidal or squamous metaplasia, and significantly proliferated into the lumen of the stomach, forming papillary structures. The epithelial height and stomach weight were six-fold greater than in non-infected controls. Phylogenetic analyses based on small subunit rRNA, Cryptosporidium oocyst wall protein, thrombospondin-related adhesive protein of Cryptosporidium-1, heat shock protein 70, actin, heat shock protein 90 (MS2), MS1, MS3, and M16 gene sequences revealed that C. proliferans is genetically distinct from C. muris and other previously described Cryptosporidium species.
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Affiliation(s)
- Martin Kváč
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
- * E-mail:
| | - Nikola Havrdová
- Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Lenka Hlásková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Tereza Daňková
- Grammar School and High School of Economics, Vimperk, Czech Republic
| | - Jiří Kanděra
- Grammar School and High School of Economics, Vimperk, Czech Republic
| | - Jana Ježková
- Faculty of Science, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Jiří Vítovec
- Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Bohumil Sak
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Ynes Ortega
- Center for Food Safety, Department of Food Science & Technology, University of Georgia, Griffin, Georgia, United States of America
| | - Lihua Xiao
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - David Modrý
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Department of Pathology and Parasitology, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic
- CEITEC VFU, Brno, Czech Republic
| | | | - Veronika Prantlová
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
- Faculty of Agriculture, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - John McEvoy
- Veterinary and Microbiological Sciences Department, North Dakota State University, Fargo, North Dakota, United States of America
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In vitro excystation of Cryptosporidium muris oocysts and viability of released sporozoites in different incubation media. Parasitol Res 2015; 115:1113-21. [PMID: 26678654 DOI: 10.1007/s00436-015-4841-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 11/19/2015] [Indexed: 10/22/2022]
Abstract
This study aimed to evaluate and document the excystation process of Cryptosporidium muris oocysts in various incubation media, and to monitor the behaviour of excysting and freshly excysted sporozoites. A test of oocyst viability, using fluorescent double staining with fluorescein diacetate and propidium iodide, was performed prior to each experimental assay. Light microscope observations confirmed that relatively often only three sporozoites were released; the fourth one either left the oocyst later together with a residual body or remained trapped within the oocyst wall. These results suggest that successful oocyst excystation is not limited by the viability of all four sporozoites. Darkening of oocysts to opaque and their specific movement (the so-called "oocyst dancing") preceded the final excystation and liberation of sporozoites, while the dormant oocysts appeared refractive. The process of excystation in C. muris is not gradual as generally described in cryptosporidia but very rapid in an eruptive manner. Experiments were performed using oocysts stored at 4 °C for various time periods, as well as oocysts freshly shed from host rodents (Mastomys coucha) of different ages. The most suitable medium supporting high excystation rate (76 %) and prolonged motility of sporozoites was RPMI 1640, enriched with 5 % bovine serum albumin (BSA). Our results emphasize that to reliably evaluate the success of in vitro excystation of cryptosporidia, not only the number of released sporozoites in a set time period should be taken into consideration but also their subsequent activity (motility), as it is expected to be essential for the invasion of host cells.
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Paziewska-Harris A, Singer M, Schoone G, Schallig H. Quantitative analysis of Cryptosporidium growth in in vitro culture--the impact of parasite density on the success of infection. Parasitol Res 2015; 115:329-37. [PMID: 26435485 DOI: 10.1007/s00436-015-4751-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 09/17/2015] [Indexed: 11/29/2022]
Abstract
Cryptosporidium is an important waterborne pathogen for which no treatment or vaccination is available. This study set out to quantify DNA replication of Cryptosporidium parvum in vitro. Cryptosporidium DNA could be detected at up to 60 % of input level in both host-cell-free and host cell containing cultures 6 days after infection with living sporozoites, but was lost within 2 days in cultures inoculated with UV-inactivated sporozoites. Total DNA increased between days 2 and 6, evidence of successful DNA replication in both cell-free and host-cell-containing cultures. Overall however, only a small fraction (up to 5 %) of parasite DNA could be found associated with host cells or bound to plastic of the cell-free cultures, and the majority of parasite DNA was present in the cell culture medium, separable by simple decantation. After 2 days, in host-cell-containing cultures, the parasite DNA could be concentrated by slow centrifugation, suggesting that it was associated with intact parasite cells, but at 6 days, the majority could not be centrifuged and is therefore thought to have represented copies associated with dead and degraded parasites. In cell-free cultures and in larger plates, the majority of DNA was in this form. Performance of the parasite was best in small culture plates, and least in the largest plate sizes. We interpret these results as suggesting that Cryptosporidium sporozoites first bind to the host cell monolayer or to the plasticware, but then by 2 days, there has been a substantial release of parasites back into the medium. Host-cell-free cultures also supported modest replication and may have represented DNA synthesis in cells beginning merogony. The role of the host cells is unclear, as so much of the parasite DNA is released into the medium. Host cells may provide a feeder role, conditioning the medium for Cryptosporidium development.
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Affiliation(s)
- Anna Paziewska-Harris
- KIT Biomedical Research, Royal Tropical Institute, Meibergdreef 39, 1105 AZ, Amsterdam, The Netherlands.
| | - Martin Singer
- Current address: Laboratory of Immunogenetics, Department of Medical Microbiology and Infection Control, VU University Medical Center, Van der Boechorststraat 7, 1081 BT, Amsterdam, The Netherlands
| | - Gerard Schoone
- KIT Biomedical Research, Royal Tropical Institute, Meibergdreef 39, 1105 AZ, Amsterdam, The Netherlands
| | - Henk Schallig
- KIT Biomedical Research, Royal Tropical Institute, Meibergdreef 39, 1105 AZ, Amsterdam, The Netherlands
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Aldeyarbi HM, Karanis P. The Ultra-Structural Similarities between Cryptosporidium parvum and the Gregarines. J Eukaryot Microbiol 2015; 63:79-85. [PMID: 26173708 DOI: 10.1111/jeu.12250] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 06/28/2015] [Accepted: 07/06/2015] [Indexed: 11/26/2022]
Abstract
Using a transmission electron microscopy-based approach, this study details the striking similarities between Cryptosporidium parvum and the gregarines during in vitro axenic development at high ultra-structural resolution. C. parvum zoites displayed three unusual regions within uninucleated parasites: epimerite-like, protomerite-like, and the cell body; these regions exhibited a high degree of morphological similarity to gregarine-like trophozoites. The presence of a mucron-like bulging structure at the side of the free ovoid gregarine-like zoites was observed after 2 h of cultivation. An irregular pattern of epicytic-like folds were found to cover the surface of the parasites 24 h postcultivation. Some extracellular stages were paired in laterocaudal or side-side syzygy, with the presence of a fusion zone between some of these zoites. The present findings are in agreement with phylogenetic studies that have proposed a sister relationship with gregarines. Cryptosporidium appears to exhibit tremendous variety in cell structure depending on the surrounding environment, thereby mimicking the "primitive" gregarines in terms of the co-evolution strategy between the parasites and their environments. Given this degree of similarity, different aspects of the evolutionary biology of Cryptosporidium need to be examined, considering the knowledge gained from the study of gregarines.
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Affiliation(s)
- Hebatalla M Aldeyarbi
- Center for Anatomy, Institute I, University of Cologne, Joseph-Stelzmann-Street 9, 50937, Cologne, Germany.,Department of Parasitology, Faculty of Medicine, Suez Canal University, Ismailia, 41522, Egypt
| | - Panagiotis Karanis
- Medical School, University of Cologne, Cologne, Germany.,Thousand Talents Plan of the Chinese Government, Center for Biomedicine and Infectious Diseases, Qinghai Academy of Animal Science and Veterinary Medicine, Xining, China
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10
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Valigurová A, Paskerova GG, Diakin A, Kováčiková M, Simdyanov TG. Protococcidian Eleutheroschizon duboscqi, an Unusual Apicomplexan Interconnecting Gregarines and Cryptosporidia. PLoS One 2015; 10:e0125063. [PMID: 25915503 PMCID: PMC4411025 DOI: 10.1371/journal.pone.0125063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 03/20/2015] [Indexed: 01/07/2023] Open
Abstract
This study focused on the attachment strategy, cell structure and the host-parasite interactions of the protococcidian Eleutheroschizon duboscqi, parasitising the polychaete Scoloplos armiger. The attached trophozoites and gamonts of E. duboscqi were detected at different development stages. The parasite develops epicellularly, covered by a host cell-derived, two-membrane parasitophorous sac forming a caudal tipped appendage. Staining with Evans blue suggests that this tail is protein-rich, supported by the presence of a fibrous substance in this area. Despite the ultrastructural evidence for long filaments in the tail, it stained only weakly for F-actin, while spectrin seemed to accumulate in this area. The attachment apparatus consists of lobes arranged in one (trophozoites) or two (gamonts) circles, crowned by a ring of filamentous fascicles. During trophozoite maturation, the internal space between the parasitophorous sac and parasite turns translucent, the parasite trilaminar pellicle seems to reorganise and is covered by a dense fibrous glycocalyx. The parasite surface is organised in broad folds with grooves in between. Micropores are situated at the bottom of the grooves. A layer of filaments organised in bands, underlying the folds and ending above the attachment fascicles, was detected just beneath the pellicle. Confocal microscopy, along with the application of cytoskeletal drugs (jasplakinolide, cytochalasin D, oryzalin) confirmed the presence of actin and tubulin polymerised forms in both the parasitophorous sac and the parasite, while myosin labelling was restricted to the sac. Despite positive tubulin labelling, no microtubules were detected in mature stages. The attachment strategy of E. duboscqi shares features with that of cryptosporidia and gregarines, i.e. the parasite itself conspicuously resembles an epicellularly located gregarine, while the parasitophorous sac develops in a similar manner to that in cryptosporidia. This study provides a re-evaluation of epicellular development in other apicomplexans and directly compares their niche with that of E. duboscqi.
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Affiliation(s)
- Andrea Valigurová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
- * E-mail:
| | - Gita G. Paskerova
- Department of Invertebrate Zoology, Faculty of Biology, Saint-Petersburg State University, Universitetskaya emb. 7/9, St. Petersburg, 199034, Russian Federation
| | - Andrei Diakin
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
| | - Magdaléna Kováčiková
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37, Brno, Czech Republic
| | - Timur G. Simdyanov
- Department of Invertebrate Zoology, Faculty of Biology, Lomonosov Moscow State University, Leninskiye Gory 1–12, Moscow, 119234, Russian Federation
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Koh W, Thompson A, Edwards H, Monis P, Clode PL. Extracellular excystation and development of Cryptosporidium: tracing the fate of oocysts within Pseudomonas aquatic biofilm systems. BMC Microbiol 2014; 14:281. [PMID: 25403949 PMCID: PMC4236811 DOI: 10.1186/s12866-014-0281-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 10/30/2014] [Indexed: 11/29/2022] Open
Abstract
Background Aquatic biofilms often serve as environmental reservoirs for microorganisms and provide them with a nutrient-rich growth environment under harsh conditions. With regard to Cryptosporidium, biofilms can serve as environmental reservoirs for oocysts, but may also support the growth of additional Cryptosporidium stages. Results Here we used confocal laser scanning microscopy, scanning electron microscopy (SEM), and flow cytometry to identify and describe various Cryptosporidium developmental stages present within aquatic biofilm systems, and to directly compare these to stages produced in cell culture. We also show that Cryptosporidium has the ability to form a parasitophorous vacuole independently, in a host-free biofilm environment, potentially allowing them to complete an extracellular life cycle. Correlative data from confocal and SEM imaging of the same cells confirmed that the observed developmental stages (including trophozoites, meronts, and merozoites) were Cryptosporidium. These microscopy observations were further supported by flow cytometric analyses, where excysted oocyst populations were detected in 1, 3 and 6 day-old Cryptosporidium-exposed biofilms, but not in biofilm-free controls. Conclusions These observations not only highlight the risk that aquatic biofilms pose in regards to Cryptosporidium outbreaks from water distribution systems, but further indicate that even simple biofilms are able to stimulate oocyst excystation and support the extracellular multiplication and development of Cryptosporidium within aquatic environments. Electronic supplementary material The online version of this article (doi:10.1186/s12866-014-0281-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wan Koh
- School of Veterinary and Life Sciences, Murdoch University, South Street, Murdoch 6150, WA, Australia.
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Valigurová A, Vaškovicová N, Musilová N, Schrével J. The enigma of eugregarine epicytic folds: where gliding motility originates? Front Zool 2013; 10:57. [PMID: 24053424 PMCID: PMC3849649 DOI: 10.1186/1742-9994-10-57] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2013] [Accepted: 08/24/2013] [Indexed: 11/12/2022] Open
Abstract
Background In the past decades, many studies focused on the cell motility of apicomplexan invasive stages as they represent a potential target for chemotherapeutic intervention. Gregarines (Conoidasida, Gregarinasina) are a heterogeneous group that parasitize invertebrates and urochordates, and are thought to be an early branching lineage of Apicomplexa. As characteristic of apicomplexan zoites, gregarines are covered by a complicated pellicle, consisting of the plasma membrane and the closely apposed inner membrane complex, which is associated with a number of cytoskeletal elements. The cell cortex of eugregarines, the epicyte, is more complicated than that of other apicomplexans, as it forms various superficial structures. Results The epicyte of the eugregarines, Gregarina cuneata, G. polymorpha and G. steini, analysed in the present study is organised in longitudinal folds covering the entire cell. In mature trophozoites and gamonts, each epicytic fold exhibits similar ectoplasmic structures and is built up from the plasma membrane, inner membrane complex, 12-nm filaments, rippled dense structures and basal lamina. In addition, rib-like myonemes and an ectoplasmic network are frequently observed. Under experimental conditions, eugregarines showed varied speeds and paths of simple linear gliding. In all three species, actin and myosin were associated with the pellicle, and this actomyosin complex appeared to be restricted to the lateral parts of the epicytic folds. Treatment of living gamonts with jasplakinolide and cytochalasin D confirmed that actin actively participates in gregarine gliding. Contributions to gliding of specific subcellular components are discussed. Conclusions Cell motility in gregarines and other apicomplexans share features in common, i.e. a three-layered pellicle, an actomyosin complex, and the polymerisation of actin during gliding. Although the general architecture and supramolecular organisation of the pellicle is not correlated with gliding rates of eugregarines, an increase in cytoplasmic mucus concentration is correlated. Furthermore, our data suggest that gregarines utilize several mechanisms of cell motility and that this is influenced by environmental conditions.
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Affiliation(s)
- Andrea Valigurová
- Department of Botany and Zoology, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic.
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Ehrenman K, Wanyiri JW, Bhat N, Ward HD, Coppens I. Cryptosporidium parvum scavenges LDL-derived cholesterol and micellar cholesterol internalized into enterocytes. Cell Microbiol 2013; 15:1182-97. [PMID: 23311949 DOI: 10.1111/cmi.12107] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 12/13/2012] [Accepted: 12/27/2012] [Indexed: 11/26/2022]
Abstract
Cryptosporidium spp. are responsible for devastating diarrhoea in immunodeficient individuals. In the intestinal tract, the developmental stages of the parasite are confined to the apical surfaces of epithelial cells. Upon invasion, Cryptosporidium incorporates the microvillous membrane of the enterocyte to form the parasitophorous vacuole (PV) and sequesters itself from the host cytoplasm by rearranging the host cytoskeleton. Cryptosporidium parvum has minimal anabolic capabilities and relies on transporters and salvage pathways to meet its basic metabolic requirements. The cholesterol salvage pathway is crucial for the development of protozoan parasites. In this study, we have examined the sources of cholesterol from C. parvum infecting enterocytes. We illustrated that the intracellular stages of Cryptosporidium as well as the oocysts shed by the host, contain cholesterol. Incubation of infected enterocytes in lipoprotein-free medium impairs parasite development and results in substantial decrease in cholesterol content associated with the PV. Among lipoproteins, LDL constitutes an important source of cholesterol for Cryptosporidium. Dietary cholesterol incorporated into micelles is internalized into enterocytes by the NPC1L1 transporter. We showed that C. parvum also obtains cholesterol from micelles in enterocytes.Pharmacological blockade of NPC1L1 function by ezetimibe or moderate downregulation of NPC1L1 expression decreases parasite infectivity. These observations indicate that, despite its dual sequestration from the intestinal lumen and the host cytoplasm, C. parvum can, in fact, obtain cholesterol both from the gut's lumen and the host cell. This study highlights the evolutionary advantages for epicellular pathogens to access to nutrients from the outside and inside of the host cell.
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Affiliation(s)
- Karen Ehrenman
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
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