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Cruz-Bustos T, Dolezal M, Feix AS, Ruttkowski B, Hummel K, Razzazi-Fazeli E, Joachim A. Unravelling the sexual developmental biology of Cystoisospora suis, a model for comparative coccidian parasite studies. Front Cell Infect Microbiol 2023; 13:1271731. [PMID: 37953800 PMCID: PMC10635411 DOI: 10.3389/fcimb.2023.1271731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 09/28/2023] [Indexed: 11/14/2023] Open
Abstract
Introduction The apicomplexan parasite Cystoisospora suis has global significance as an enteropathogen of suckling piglets. Its intricate life cycle entails a transition from an asexual phase to sexual development, ultimately leading to the formation of transmissible oocysts. Methods To advance our understanding of the parasite's cellular development, we complemented previous transcriptome studies by delving into the proteome profiles at five distinct time points of in vitro cultivation through LC/MS-MS analysis. Results A total of 1,324 proteins were identified in the in vitro developmental stages of C. suis, and 1,082 proteins were identified as significantly differentially expressed. Data are available via ProteomeXchange with identifier PXD045050. We performed BLAST, GO enrichment, and KEGG pathway analyses on the up- and downregulated proteins to elucidate correlated events in the C. suis life cycle. Our analyses revealed intriguing metabolic patterns in macromolecule metabolism, DNA- and RNA-related processes, proteins associated with sexual stages, and those involved in cell invasion, reflecting the adaptation of sexual stages to a nutrient-poor and potentially stressful extracellular environment, with a focus on enzymes involved in metabolism and energy production. Discussion These findings have important implications for understanding the developmental biology of C. suis as well as other, related coccidian parasites, such as Eimeria spp. and Toxoplasma gondii. They also support the role of C. suis as a new model for the comparative biology of coccidian tissue cyst stages.
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Affiliation(s)
- Teresa Cruz-Bustos
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Marlies Dolezal
- Platform for Bioinformatics and Biostatistics, Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Anna Sophia Feix
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Bärbel Ruttkowski
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Karin Hummel
- VetCore Facility (Proteomics), University of Veterinary Medicine Vienna, Vienna, Austria
| | - Ebrahim Razzazi-Fazeli
- VetCore Facility (Proteomics), University of Veterinary Medicine Vienna, Vienna, Austria
| | - Anja Joachim
- Department of Pathobiology, Institute of Parasitology, University of Veterinary Medicine Vienna, Vienna, Austria
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Feix AS, Cruz-Bustos T, Ruttkowski B, Joachim A. Inhibition of sexual stage-specific proteins results in reduced numbers of sexual stages and oocysts of Cystoisospora suis (Apicomplexa: Coccidia) in vitro. Int J Parasitol 2022; 52:829-841. [PMID: 36270547 DOI: 10.1016/j.ijpara.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/05/2022]
Abstract
Parasites of the order Coccidia (phylum: Alveolata, subphylum: Apicomplexa) have sophisticated life cycles that include a switch from asexual to sexual development, characterised by distinct cell types. During the development of gametes (gamogony), substantial changes occur at the cellular and subcellular levels, leading to cell fusion of micro- and microgametes, and the development of a zygote that forms a protective outer layer for environmental survival as an oocyst, the transmissible stage. Studies on the porcine coccidian Cystoisospora suis already identified changes in transcription profiles during different time points in the parasite's development and identified proteins with potential roles in the sexual development of this parasite. Here, we focus on three proteins that are possibly involved in the sexual development of C. suis. Enkurin and hapless protein 2 (HAP2) play important roles in signal transduction and gamete fusion during the fertilisation process, and oocyst wall forming protein 1 (OWP1) is a homologue of oocyst wall forming proteins of related parasites. We evaluated their locations in the different life cycle stages of C. suis and their inhibition by specific antibodies in vitro. Immunolocalization detected enkurin in merozoites and sporulated oocysts, HAP2 in merozoites and microgamonts, and OWP2 in merozoites, macrogamonts, oocysts and sporozoites. Up to 100% inhibition of the development of sexual stages and oocyst formation with purified chicken immunoglobulin IgY sera against recombinant enkurin, HAP2, and especially OWP1, were demonstrated. We conclude that the three investigated sexual stage-specific proteins constitute targets for in vivo intervention strategies to interrupt parasite development and transmission to susceptible hosts.
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Affiliation(s)
- Anna Sophia Feix
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinärplatz 1, Vienna A-1210, Austria.
| | - Teresa Cruz-Bustos
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinärplatz 1, Vienna A-1210, Austria
| | - Bärbel Ruttkowski
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinärplatz 1, Vienna A-1210, Austria
| | - Anja Joachim
- Institute of Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinärplatz 1, Vienna A-1210, Austria
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Cruz-Bustos T, Feix AS, Ruttkowski B, Joachim A. Sexual Development in Non-Human Parasitic Apicomplexa: Just Biology or Targets for Control? Animals (Basel) 2021; 11:ani11102891. [PMID: 34679913 PMCID: PMC8532714 DOI: 10.3390/ani11102891] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 12/17/2022] Open
Abstract
Simple Summary Cellular reproduction is a key part of the apicomplexan life cycle, and both mitotic (asexual) and meiotic (sexual) cell divisions produce new individual cells. Sexual reproduction in most eukaryotic taxa indicates that it has had considerable success during evolution, and it must confer profound benefits, considering its significant costs. The phylum Apicomplexa consists of almost exclusively parasitic single-celled eukaryotic organisms that can affect a wide host range of animals from invertebrates to mammals. Their development is characterized by complex steps in which asexual and sexual replication alternate and the fertilization of a macrogamete by a microgamete results in the formation of a zygote that undergoes meiosis, thus forming a new generation of asexual stages. In apicomplexans, sex is assumed to be induced by the (stressful) condition of having to leave the host, and either gametes or zygotes (or stages arising from it) are transmitted to a new host. Therefore, sex and meiosis are linked to parasite transmission, and consequently dissemination, which are key to the parasitic lifestyle. We hypothesize that improved knowledge of the sexual biology of the Apicomplexa will be essential to design and implement effective transmission-blocking strategies for the control of the major parasites of this group. Abstract The phylum Apicomplexa is a major group of protozoan parasites including gregarines, coccidia, haemogregarines, haemosporidia and piroplasms, with more than 6000 named species. Three of these subgroups, the coccidia, hemosporidia, and piroplasms, contain parasites that cause important diseases of humans and animals worldwide. All of them have complex life cycles involving a switch between asexual and sexual reproduction, which is key to their development. Fertilization (i.e., fusion of female and male cells) results in the formation of a zygote that undergoes meiosis, forming a new generation of asexual stages. In eukaryotes, sexual reproduction is the predominant mode of recombination and segregation of DNA. Sex is well documented in many protist groups, and together with meiosis, is frequently linked with transmission to new hosts. Apicomplexan sexual stages constitute a bottleneck in the life cycle of these parasites, as they are obligatory for the development of new transmissible stages. Consequently, the sexual stages represent attractive targets for vaccination. Detailed understanding of apicomplexan sexual biology will pave the way for the design and implementation of effective transmission-blocking strategies for parasite control. This article reviews the current knowledge on the sexual development of Apicomplexa and the progress in transmission-blocking vaccines for their control, their advantages and limitations and outstanding questions for the future.
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Abstract
BACKGROUND The porcine coccidium Cystoisospora suis is characterized by a complex life-cycle during which asexual multiplication is followed by sexual development with two morphologically distinct cell types, the micro- and macrogametes. Genes related to the sexual stages and cell cycle progression were previously identified in related Apicomplexa. Dynein light chain type 1 and male gamete fusion factor HAP2 are restricted to microgametes. Tyrosine-rich proteins and oocyst wall proteins are a part of the oocyst wall. The Rad51/Dmc1-like protein and Nima-related protein kinases are associated with the cell cycle and fertilization process. Here, the sexual stages of C. suis were characterized in vitro morphologically and for temporal expression changes of the mentioned genes to gain insight into this poorly known phase of coccidian development. METHODS Sexual stages of C. suis developing in vitro in porcine intestinal epithelial cells were examined by light and electron microscopy. The transcriptional levels of genes related to merozoite multiplication and sexual development were evaluated by quantitative real-time PCR at different time points of cultivation. Transcription levels were compared for parasites in culture supernatants at 6-9 days of cultivation (doc) and intracellular parasites at 6-15 doc. RESULTS Sexual stage of C. suis was detected during 8-11 doc in vitro. Microgamonts (16.8 ± 0.9 µm) and macrogamonts (16.6 ± 1.1 µm) are very similar in shape and size. Microgametes had a round body (3.5 ± 0.5 µm) and two flagella (11.2 ± 0.5 µm). Macrogametes were spherical with a diameter of 12.1 ± 0.5 µm. Merozoite gene transcription peaked on 10 doc and then declined. Genes related to the sexual stages and cell cycle showed an upregulation with a peak on 13 doc, after which they declined. CONCLUSIONS The present study linked gene expression changes to the detailed morphological description of C. suis sexual development in vitro, including fertilization, meiosis and oocyst formation in this unique model for coccidian parasites. Following this process at the cellular and molecular level will elucidate details on potential bottlenecks of C. suis development (applicable for coccidian parasites in general) which could be exploited as a novel target for control.
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Affiliation(s)
- Anna Sophia Feix
- Institute for Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, Vienna, 1210 Austria
| | - Teresa Cruz-Bustos
- Institute for Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, Vienna, 1210 Austria
| | - Bärbel Ruttkowski
- Institute for Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, Vienna, 1210 Austria
| | - Anja Joachim
- Institute for Parasitology, Department of Pathobiology, University of Veterinary Medicine Vienna, Veterinaerplatz 1, Vienna, 1210 Austria
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Lander N, Cruz-Bustos T, Docampo R. A CRISPR/Cas9-riboswitch-Based Method for Downregulation of Gene Expression in Trypanosoma cruzi. Front Cell Infect Microbiol 2020; 10:68. [PMID: 32175288 PMCID: PMC7056841 DOI: 10.3389/fcimb.2020.00068] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/11/2020] [Indexed: 12/18/2022] Open
Abstract
Few genetic tools were available to work with Trypanosoma cruzi until the recent introduction of the CRISPR/Cas9 technique for gene knockout, gene knock-in, gene complementation, and endogenous gene tagging. Riboswitches are naturally occurring self-cleaving RNAs (ribozymes) that can be ligand-activated. Results from our laboratory recently demonstrated the usefulness of the glmS ribozyme from Bacillus subtilis, which has been shown to control reporter gene expression in response to exogenous glucosamine, for gene silencing in Trypanosoma brucei. In this work we used the CRISPR/Cas9 system for endogenously tagging T. cruzi glycoprotein 72 (TcGP72) and vacuolar proton pyrophosphatase (TcVP1) with the active (glmS) or inactive (M9) ribozyme. Gene tagging was confirmed by PCR and protein downregulation was verified by western blot analyses. Further phenotypic characterization was performed by immunofluorescence analysis and quantification of growth in vitro. Our results indicate that the method was successful in silencing the expression of both genes without the need of glucosamine in the medium, suggesting that T. cruzi produces enough levels of endogenous glucosamine 6-phosphate to stimulate the glmS ribozyme activity under normal growth conditions. This method could be useful to obtain knockdowns of essential genes in T. cruzi and to validate potential drug targets in this parasite.
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Affiliation(s)
- Noelia Lander
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Teresa Cruz-Bustos
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, United States.,Department of Cellular Biology, University of Georgia, Athens, GA, United States
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Cruz-Bustos T, Ibarrola-Vannucci AK, Díaz-Lozano I, Ramírez JL, Osuna A. Characterization and functionality of two members of the SPFH protein superfamily, prohibitin 1 and 2 in Leishmania major. Parasit Vectors 2018; 11:622. [PMID: 30514373 PMCID: PMC6278115 DOI: 10.1186/s13071-018-3195-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 11/09/2018] [Indexed: 01/01/2023] Open
Abstract
Background Leishmaniasis, a disease caused by parasites of the genus Leishmania, infects roughly 12 million people worldwide, with about two million new cases per year. Prohibitins (PHBs) are highly conserved proteins belonging to the stomatin-prohibitin flotillin-HflC/K (SPFH) protein superfamily. In this study, we examine the potential functions of two proteins of Leishmania major, PHB1 and PHB2, as well as how they might help protect the protozoan against oxidative stress. Results By immunolocalization in the parasite cells, PHB1 appeared in the mitochondria and plasma membrane, whereas PHB2 was grouped in the nucleus. When Leishmania cells were under oxidative stress, PHB1 migrates towards the plasma membrane and the paraxial rod, while PHB2 remained in the nucleus and near the kinetoplast. PHB1 presented higher mRNA levels than PHB2 in the amastigotes and the infective metacyclic forms. The mRNA expression of both prohibitins was affected by the presence of the Fe3+ ion. PHBs inhibited the Fenton reaction, where reactive oxygen species could nick DNA, implying that they play a crucial role in controlling oxidative stress. Conclusions Here, we propose that PHBs may help to protect membranes and DNA against superoxide ions, thus enhancing the survival capacity of the protozoan by controlling the ROS within the phagosome of the macrophages where the parasite multiplies.
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Affiliation(s)
- Teresa Cruz-Bustos
- Department of Parasitology, Faculty of Science, University of Granada, Granada, Spain
| | | | - Isabel Díaz-Lozano
- Department of Parasitology, Faculty of Science, University of Granada, Granada, Spain.,Karolinska Institute, Stockholm, Sweden
| | - José Luis Ramírez
- Instituto de Estudios Avanzados, (IDEA), Caracas, Venezuela.,Instituto de Biología Experimental, Universidad Central de Venezuela, Caracas, Venezuela
| | - A Osuna
- Department of Parasitology, Faculty of Science, University of Granada, Granada, Spain. .,Molecular Parasitology Research Group (CTS-183), Institute of Biotechnology, University of Granada, Granada, Spain.
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Abstract
Membrane proteins in trypanosomatids are, in general, weakly expressed and confirmation of their subcellular localization frequently requires their overexpression with epitope tags. However, overexpression can lead to mislocalization of the probes. Viswanathan et al. (Nat. Methods, 2015, 12:568) described high performance tags for localization of weakly expressed proteins. We report here the use of these protein tags, named "spaghetti monster," for CRISPR/Cas9-mediated C-terminal endogenous tagging of Trypanosoma cruzi to localize two weakly expressed transient receptor potential channels to acidic compartments. The results indicate that this method will improve the detection of membrane proteins in T. cruzi.
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Affiliation(s)
- Teresa Cruz-Bustos
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602
| | - Silvia N J Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602.,Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602.,Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
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Cruz-Bustos T, Ramakrishnan S, Cordeiro CD, Ahmed MA, Docampo R. A Riboswitch-based Inducible Gene Expression System for Trypanosoma brucei. J Eukaryot Microbiol 2018; 65:412-421. [PMID: 29265590 DOI: 10.1111/jeu.12493] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 12/08/2017] [Accepted: 12/08/2017] [Indexed: 01/13/2023]
Abstract
Generation of conditional mutants in Trypanosoma brucei can be done by the use of RNA interference (RNAi). However, RNAi frequently produces off target effects. Here, we present an alternative strategy in which the glmS ribozyme is inserted in the C-terminal region of one allele of a GOI and effectively knocks it down in response to the presence of glucosamine in the culture medium. Using several endogenous genes, we show that the glmS ribozyme cleaves the mRNA in vivo leading to reduction in mRNA and protein expression following glucosamine treatment in both T. brucei procyclic and bloodstream forms. Glucosamine-induced ribozyme activation can be rapidly reversed by removing the inducer. In summary, the glmS ribozyme could be used as a tool to study essential genes in T. brucei.
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Affiliation(s)
- Teresa Cruz-Bustos
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Srinivasan Ramakrishnan
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Ciro D Cordeiro
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Michael A Ahmed
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
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Rodríguez-Serrano F, Mut-Salud N, Cruz-Bustos T, Gomez-Samblas M, Carrasco E, Garrido JM, López-Jaramillo FJ, Santoyo-Gonzalez F, Osuna A. Functionalized immunostimulating complexes with protein A via lipid vinyl sulfones to deliver cancer drugs to trastuzumab-resistant HER2-overexpressing breast cancer cells. Int J Nanomedicine 2016; 11:4777-4785. [PMID: 27698563 PMCID: PMC5034911 DOI: 10.2147/ijn.s112560] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Background Around 20%–30% of breast cancers overexpress the proto-oncogene human epidermal growth receptor 2 (HER2), and they are characterized by being very invasive. Therefore, many current studies are focused on testing new therapies against tumors that overexpress this receptor. In particular, there exists major interest in new strategies to fight breast cancer resistant to trastuzumab (Tmab), a humanized antibody that binds specifically to HER2 interfering with its mitogenic signaling. Our team has previously developed immunostimulating complexes (ISCOMs) as nanocapsules functionalized with lipid vinyl sulfones, which can incorporate protein A and bind to G immunoglobulins that makes them very flexible nanocarriers. Methods and results The aim of this in vitro study was to synthesize and evaluate a drug delivery system based on protein A-functionalized ISCOMs to target HER2-overexpressing cells. We describe the preparation of ISCOMs, the loading with the drugs doxorubicin and paclitaxel, the binding of ISCOMs to alkyl vinyl sulfone-protein A, the coupling of Tmab, and the evaluation in both HER2-overexpressing breast cancer cells (HCC1954) and non-overexpressing cells (MCF-7) by flow cytometry and fluorescence microscopy. Results show that the uptake is dependent on the level of overexpression of HER2, and the analysis of the cell viability reveals that targeted drugs are selective toward HCC1954, whereas MCF-7 cells remain unaffected. Conclusion Protein A-functionalized ISCOMs are versatile carriers that can be coupled to antibodies that act as targeting agents to deliver drugs. When coupling to Tmab and loading with paclitaxel or doxorubicin, they become efficient vehicles for the selective delivery of the drug to Tmab-resistant HER2-overexpressing breast cancer cells. These nanoparticles may pave the way for the development of novel therapies for poor prognosis resistant patients.
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Affiliation(s)
| | | | - Teresa Cruz-Bustos
- Molecular Biochemistry and Parasitology Research Group, Department of Parasitology, Faculty of Sciences, Institute of Biotechnology, University of Granada
| | - Mercedes Gomez-Samblas
- Molecular Biochemistry and Parasitology Research Group, Department of Parasitology, Faculty of Sciences, Institute of Biotechnology, University of Granada
| | | | | | - F Javier López-Jaramillo
- Department of Organic Chemistry, Faculty of Sciences, Institute of Biotechnology, University of Granada, Granada, Spain
| | - Francisco Santoyo-Gonzalez
- Department of Organic Chemistry, Faculty of Sciences, Institute of Biotechnology, University of Granada, Granada, Spain
| | - Antonio Osuna
- Molecular Biochemistry and Parasitology Research Group, Department of Parasitology, Faculty of Sciences, Institute of Biotechnology, University of Granada
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Osuna-Mascaró AJ, Cruz-Bustos T, Marin F, Checa AG. Ultrastructure of the Interlamellar Membranes of the Nacre of the Bivalve Pteria hirundo, Determined by Immunolabelling. PLoS One 2015; 10:e0122934. [PMID: 25909912 PMCID: PMC4409017 DOI: 10.1371/journal.pone.0122934] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/24/2015] [Indexed: 11/18/2022] Open
Abstract
The current model for the ultrastructure of the interlamellar membranes of molluscan nacre imply that they consist of a core of aligned chitin fibers surrounded on both sides by acidic proteins. This model was based on observations taken on previously demineralized shells, where the original structure had disappeared. Despite other earlier claims, no direct observations exist in which the different components can be unequivocally discriminated. We have applied different labeling protocols on non-demineralized nacreous shells of the bivalve Pteria. With this method, we have revealed the disposition and nature of the different fibers of the interlamellar membranes that can be observed on the surface of the nacreous shell of the bivalve Pteria hirundo by high resolution scanning electron microscopy (SEM). The minor chitin component consists of very thin fibers with a high aspect ratio and which are seemingly disoriented. Each fiber has a protein coat, which probably forms a complex with the chitin. The chitin-protein-complex fibers are embedded in an additional proteinaceous matrix. This is the first time in which the sizes, positions and distribution of the chitin fibers have been observed in situ.
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Affiliation(s)
- Antonio J. Osuna-Mascaró
- Departamento de Estratigrafía y Paleontología, Facultad de Ciencias, Universidad de Granada, Av. Fuentenueva, S/N 18071, Granada, Spain
- * E-mail:
| | - Teresa Cruz-Bustos
- Departamento de Bioquímica y Parasitología Molecular, Facultad de Ciencias, Universidad de Granada, Av. Fuentenueva, S/N 18071, Granada, Spain
| | - Frédéric Marin
- UMR CNRS 6282 Biogéosciences, Université de Bourgogne, 6 Bd. Gabriel, 21000, Dijon, France
| | - Antonio G. Checa
- Departamento de Estratigrafía y Paleontología, Facultad de Ciencias, Universidad de Granada, Av. Fuentenueva, S/N 18071, Granada, Spain
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Osuna-Mascaró A, Cruz-Bustos T, Benhamada S, Guichard N, Marie B, Plasseraud L, Corneillat M, Alcaraz G, Checa A, Marin F. The shell organic matrix of the crossed lamellar queen conch shell (Strombus gigas). Comp Biochem Physiol B Biochem Mol Biol 2014; 168:76-85. [DOI: 10.1016/j.cbpb.2013.11.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 11/19/2013] [Accepted: 11/22/2013] [Indexed: 11/26/2022]
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Cruz-Bustos T, González-González G, Morales-Sanfrutos J, Megía-Fernández A, Santoyo-González F, Osuna A. Functionalization of immunostimulating complexes (ISCOMs) with lipid vinyl sulfones and their application in immunological techniques and therapy. Int J Nanomedicine 2012; 7:5941-56. [PMID: 23233802 PMCID: PMC3518286 DOI: 10.2147/ijn.s35556] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Background Immunostimulating complexes (ISCOM)-type nanocapsules have been functionalized with lipid vinyl sulfones that anchor to them via the hydrophobic zone of their structure and can be charged with pharmacologically active molecules or macromolecules. These functionalized nanocapsules can incorporate protein A and bind to G immunoglobulins (IgGs) to make vehicles directed at the surface antigens of infectious agents, tumor cells, or receptor cells and deliver the encapsulated molecules in a highly specific way. They may be of particular use in pharmacological treatments with highly toxic molecules that should not be used in solution whenever it can be avoided. When bound to antibodies they can be used in biological processes that require the delivery or presentation of macromolecules to certain specific cells, in immunization processes for instance, or in diagnostic immunological techniques, as they are able to transport both the secondary antibodies and the reaction labels. Methods and results We describe the preparation of ISCOMs, the binding to the ISCOMS of newly synthesized compounds composed of chain alkyl vinyl sulfone, and the subsequent binding of the vinyl-sulfone compounds to IgGs. Within this context, a compound deriving from cholesterol functionalized with vinyl sulfone and used together with cholesterol in varying proportions has been linked to the structure of the ISCOMs and bound to protein A–IgG. This functionalization in no way altered the form or structure of the ISCOMs and allowed the nanocapsules carrying the specific IgGs to bind to forms of Trypanosoma cruzi against which antibodies had been developed. The fact that functionalized ISCOMs containing antibodies could deliver actinomycin D directly to the parasite meant that the effective dose of the antibiotic could be reduced very significantly. Conclusion We have developed ISCOM-type nanocapsules functionalized with lipid vinyl sulfone capable of anchoring to the surface of functional IgGs, which favors the recognition and transport of these nanocapsules precisely to certain kinds of cell.
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Affiliation(s)
- Teresa Cruz-Bustos
- Molecular Biochemistry and Parasitology Research Group, Department of Parasitology, Institute of Biotechnology, Faculty of Sciences, University of Granada, Granada, Spain
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