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Vance GM, Khouri MI, Neto APDS, James S, Leite LCC, Farias LP, Wilson RA. Antigenic epitope targets of rhesus macaques self-curing from Schistosoma mansoni infection. Front Immunol 2024; 14:1269336. [PMID: 38464672 PMCID: PMC10921417 DOI: 10.3389/fimmu.2023.1269336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Accepted: 09/22/2023] [Indexed: 03/12/2024] Open
Abstract
The self-cure of rhesus macaques from a schistosome infection and their subsequent strong immunity to a cercarial challenge should provide novel insights into the way these parasites can be eliminated by immunological attack. High-density arrays comprising overlapping 15-mer peptides from target proteins printed on glass slides can be used to screen sera from host species to determine antibody reactivity at the single epitope level. Careful selection of proteins, based on compositional studies, is crucial to encompass only those exposed on or secreted from the intra-mammalian stages and is intended to focus the analysis solely on targets mediating protection. We report the results of this approach using two pools of sera from hi- and lo-responder macaques undergoing self-cure, to screen arrays comprising tegument, esophageal gland, and gastrodermis proteins. We show that, overall, the target epitopes are the same in both groups, but the intensity of response is twice as strong in the high responders. In addition, apart from Sm25, tegument proteins elicit much weaker responses than those originating in the alimentary tract, as was apparent in IFNγR KO mice. We also highlight the most reactive epitopes in key proteins. Armed with this knowledge, we intend to use multi-epitope constructs in vaccination experiments, which seek to emulate the self-cure process in experimental animals and potentially in humans.
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Affiliation(s)
| | - Mariana I. Khouri
- Laboratório de Inflamação e Biomarcadores, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, BA, Brazil
| | - Almiro Pires da Silva Neto
- Laboratório de Inflamação e Biomarcadores, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, BA, Brazil
| | - Sally James
- Department of Biology, University of York, York, United Kingdom
| | - Luciana C. C. Leite
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Leonardo Paiva Farias
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - R. Alan Wilson
- Department of Biology, University of York, York, United Kingdom
- Biomedical Research Institute, University of York, York, United Kingdom
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2
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Woellner-Santos D, Tahira AC, Malvezzi JVM, Mesel V, Morales-Vicente DA, Trentini MM, Marques-Neto LM, Matos IA, Kanno AI, Pereira ASA, Teixeira AAR, Giordano RJ, Leite LCC, Pereira CAB, DeMarco R, Amaral MS, Verjovski-Almeida S. Schistosoma mansoni vaccine candidates identified by unbiased phage display screening in self-cured rhesus macaques. NPJ Vaccines 2024; 9:5. [PMID: 38177171 PMCID: PMC10767053 DOI: 10.1038/s41541-023-00803-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/30/2023] [Indexed: 01/06/2024] Open
Abstract
Schistosomiasis, a challenging neglected tropical disease, affects millions of people worldwide. Developing a prophylactic vaccine against Schistosoma mansoni has been hindered by the parasite's biological complexity. In this study, we utilized the innovative phage-display immunoprecipitation followed by a sequencing approach (PhIP-Seq) to screen the immune response of 10 infected rhesus macaques during self-cure and challenge-resistant phases, identifying vaccine candidates. Our high-throughput S. mansoni synthetic DNA phage-display library encoded 99.6% of 119,747 58-mer peptides, providing comprehensive coverage of the parasite's proteome. Library screening with rhesus macaques' antibodies, from the early phase of establishment of parasite infection, identified significantly enriched epitopes of parasite extracellular proteins known to be expressed in the digestive tract, shifting towards intracellular proteins during the late phase of parasite clearance. Immunization of mice with a selected pool of PhIP-Seq-enriched phage-displayed peptides from MEG proteins, cathepsins B, and asparaginyl endopeptidase significantly reduced worm burden in a vaccination assay. These findings enhance our understanding of parasite-host immune responses and provide promising prospects for developing an effective schistosomiasis vaccine.
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Affiliation(s)
- Daisy Woellner-Santos
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ana C Tahira
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
| | - João V M Malvezzi
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
- Instituto de Matemática e Estatística, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Vinicius Mesel
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
| | - David A Morales-Vicente
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Monalisa M Trentini
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Lázaro M Marques-Neto
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Isaac A Matos
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Alex I Kanno
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Adriana S A Pereira
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
| | - André A R Teixeira
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil
- Institute for Protein Innovation, Boston, MA, USA
| | | | - Luciana C C Leite
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Carlos A B Pereira
- Instituto de Matemática e Estatística, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Ricardo DeMarco
- Instituto de Física de São Carlos, Universidade de São Paulo, São Carlos, SP, Brazil
| | - Murilo S Amaral
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil
| | - Sergio Verjovski-Almeida
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, SP, Brazil.
- Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brazil.
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Nedvědová Š, De Stefano D, Walker O, Hologne M, Miele AE. Revisiting Schistosoma mansoni Micro-Exon Gene (MEG) Protein Family: A Tour into Conserved Motifs and Annotation. Biomolecules 2023; 13:1275. [PMID: 37759676 PMCID: PMC10526429 DOI: 10.3390/biom13091275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/15/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Genome sequencing of the human parasite Schistosoma mansoni revealed an interesting gene superfamily, called micro-exon gene (meg), that encodes secreted MEG proteins. The genes are composed of short exons (3-81 base pairs) regularly interspersed with long introns (up to 5 kbp). This article recollects 35 S. mansoni specific meg genes that are distributed over 7 autosomes and one pair of sex chromosomes and that code for at least 87 verified MEG proteins. We used various bioinformatics tools to produce an optimal alignment and propose a phylogenetic analysis. This work highlighted intriguing conserved patterns/motifs in the sequences of the highly variable MEG proteins. Based on the analyses, we were able to classify the verified MEG proteins into two subfamilies and to hypothesize their duplication and colonization of all the chromosomes. Together with motif identification, we also proposed to revisit MEGs' common names and annotation in order to avoid duplication, to help the reproducibility of research results and to avoid possible misunderstandings.
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Affiliation(s)
- Štěpánka Nedvědová
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 16500 Prague, Czech Republic
- Department of Zoology and Fisheries, Center of Infectious Animal Diseases, Czech University of Life Sciences, 16500 Prague, Czech Republic
| | - Davide De Stefano
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Olivier Walker
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Maggy Hologne
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Adriana Erica Miele
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy
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4
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Zhu P, Wu K, Zhang C, Batool SS, Li A, Yu Z, Huang J. Advances in new target molecules against schistosomiasis: A comprehensive discussion of physiological structure and nutrient intake. PLoS Pathog 2023; 19:e1011498. [PMID: 37498810 PMCID: PMC10374103 DOI: 10.1371/journal.ppat.1011498] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
Schistosomiasis, a severe parasitic disease, is primarily caused by Schistosoma mansoni, Schistosoma japonicum, or Schistosoma haematobium. Currently, praziquantel is the only recommended drug for human schistosome infection. However, the lack of efficacy of praziquantel against juvenile worms and concerns about the emergence of drug resistance are driving forces behind the research for an alternative medication. Schistosomes are obligatory parasites that survive on nutrients obtained from their host. The ability of nutrient uptake depends on their physiological structure. In short, the formation and maintenance of the structure and nutrient supply are mutually reinforcing and interdependent. In this review, we focus on the structural features of the tegument, esophagus, and intestine of schistosomes and their roles in nutrient acquisition. Moreover, we introduce the significance and modes of glucose, lipids, proteins, and amino acids intake in schistosomes. We linked the schistosome structure and nutrient supply, introduced the currently emerging targets, and analyzed the current bottlenecks in the research and development of drugs and vaccines, in the hope of providing new strategies for the prevention and control of schistosomiasis.
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Affiliation(s)
- Peng Zhu
- Department of Parasitology, School of Basic Medical Science, Central South University, Changsha, China
- XiangYa School of Medicine, Central South University, Changsha, Hunan, China
| | - Kaijuan Wu
- Department of Parasitology, School of Basic Medical Science, Central South University, Changsha, China
| | - Chaobin Zhang
- Department of Parasitology, School of Basic Medical Science, Central South University, Changsha, China
- XiangYa School of Medicine, Central South University, Changsha, Hunan, China
| | - Syeda Sundas Batool
- Department of Microbiology, School of Basic Medical Science, Central South University, Changsha, Hunan, China
- China-Africa Research Center of Infectious Diseases, Central South University, Changsha, China
| | - Anqiao Li
- Department of Parasitology, School of Basic Medical Science, Central South University, Changsha, China
- XiangYa School of Medicine, Central South University, Changsha, Hunan, China
| | - Zheng Yu
- Department of Microbiology, School of Basic Medical Science, Central South University, Changsha, Hunan, China
- China-Africa Research Center of Infectious Diseases, Central South University, Changsha, China
| | - Jing Huang
- Department of Parasitology, School of Basic Medical Science, Central South University, Changsha, China
- China-Africa Research Center of Infectious Diseases, Central South University, Changsha, China
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5
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Planarians to schistosomes: an overview of flatworm cell-types and regulators. J Helminthol 2023; 97:e7. [PMID: 36644809 DOI: 10.1017/s0022149x22000621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Schistosomiasis remains a major neglected tropical disease that afflicts over 200 million people globally. Schistosomes, the aetiological agent of schistosomiasis, are parasitic flatworms that propagate between molluscan and mammalian hosts. Inside the mammalian host, schistosomes rapidly grow over 100-fold in size and develop into a sexually mature male or female that thrives in the bloodstream for several decades. Recent work has identified schistosome stem cells as the source that drives parasite transmission, reproduction and longevity. Moreover, studies have begun to uncover molecular programmes deployed by stem cells that are essential for tissue development and maintenance, parasite survival and immune evasion. Such programmes are reminiscent of neoblast-driven development and regeneration of planarians, the free-living flatworm relative of schistosomes. Over the last few decades, research in planarians has employed modern functional genomic tools that significantly enhanced our understanding of stem cell-driven animal development and regeneration. In this review, we take a broad stroke overview of major flatworm organ systems at the cellular and molecular levels. We summarize recent advances on genetic regulators that play critical roles in differentiation and maintenance of flatworm cell types. Finally, we provide perspectives on how investigation of basic parasite biology is critical to discovering new approaches to battle schistosomiasis.
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Winkelmann F, Rabes A, Reinholdt C, Koslowski N, Koczan D, Reisinger EC, Sombetzki M. Sex-Specific Modulation of the Host Transcriptome in the Spleen of Schistosoma mansoni-Infected Mice. Front Cell Infect Microbiol 2022; 12:893632. [PMID: 35865813 PMCID: PMC9294737 DOI: 10.3389/fcimb.2022.893632] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Background Schistosomiasis is a severe parasitic disease that is primarily driven by the host’s immune response to schistosome eggs trapped in tissue and by the granulomatous inflammatory and fibrotic reaction they cause. Despite significant progress in understanding the complex immunological processes involved in the relationship between schistosomes and their host, neither an effective vaccine against the infection nor anti-fibrotic drugs currently exists, making the search for new targets for schistosome drugs and vaccine candidates even more important. In order to identify new molecular targets for defense against or elimination of the parasite, we investigate herein the interplay between the host and male or female schistosomes, clearly separating this from the action of the parasite eggs. Methods For this purpose, we infected 6–8-week-old female NMRI mice with 100 male (M), female (F), or both (MF) S. mansoni cercariae and performed a comparative transcriptomic and flow cytometric analysis of their spleens. Results Principal component analysis of a total of 22,207 transcripts showed a clear clustering of the experimental groups. We identified a total of 1,293 genes in group M, 512 genes in group F, and 4,062 genes in group MF that were differentially expressed compared to naive controls. The highest percentage of regulated genes (2,972; 65.9%) was found in group MF alone, but there was a large overlap between groups M and MF (798; 17.7%) and a small overlap between groups F and MF (91; 2.0%). Only 4.5% of genes (201) were revealed to be regulated in all experimental groups (M/F/MF). In addition, we were able to show that both worm sexes trigger immune responses in an egg-independent manner (non-polarized Th1 and Th2 response), with female worms exerting less regulatory influence than males. Conclusion Our data show that adult schistosomes trigger sex-specific, egg-independent immune responses. The lists of genes regulated by adult female or male worms presented here may be useful in deciphering host–parasite interactions to identify targets for schistosome elimination.
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Affiliation(s)
- Franziska Winkelmann
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
| | - Anne Rabes
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
| | - Cindy Reinholdt
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
| | - Nicole Koslowski
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
| | - Dirk Koczan
- Institute of Immunology, University of Rostock, Rostock, Germany
| | - Emil C. Reisinger
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
| | - Martina Sombetzki
- Department of Tropical Medicine and Infectious Diseases, Center of Internal Medicine II, Rostock University Medical Center, Rostock, Germany
- *Correspondence: Martina Sombetzki,
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Abstract
INTRODUCTION Schistosomes are long-lived blood dwelling helminth parasites using intricate mechanisms to invade, mature, and reproduce inside their vertebrate hosts, whilst simultaneously deploying immune evasion strategies. Their multi-tissue organization and solid body plan presents particular problems for the definition of sub-proteomes. AREAS COVERED Here, we focus on the two host-parasite interfaces of the adult worm accessible to the immune system, namely the tegument and the alimentary tract, but also on the secretions of the infective cercaria, the migrating schistosomulum and the mature egg. In parallel, we introduce the concepts of "leakyome' and 'disintegrome' to emphasize the importance of interpreting data in the context of schistosome biology so that misleading conclusions about the distinct proteome compositions are avoided. Lastly, we highlight the possible clinical implications of the reviewed proteomic findings for pathogenesis, vaccine design and diagnostics. EXPERT OPINION Proteomics has provided considerable insights into the biology of schistosomes, most importantly for rational selection of novel vaccine candidates that might confer protective immunity, but also into the pathogenesis of schistosomiasis. However, given the increasing sensitivity of mass spectrometric instrumentation, we stress the need for care in data interpretation since schistosomes do not deviate from the fundamental rules of eukaryotic cell biology.
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Affiliation(s)
- William Castro-Borges
- Departamento de Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brasil
| | - R Alan Wilson
- Department of Biology and York Biomedical Research Institute, University of York, Heslington, York, UK
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Romero AA, Cobb SA, Collins JNR, Kliewer SA, Mangelsdorf DJ, Collins JJ. The Schistosoma mansoni nuclear receptor FTZ-F1 maintains esophageal gland function via transcriptional regulation of meg-8.3. PLoS Pathog 2021; 17:e1010140. [PMID: 34910770 PMCID: PMC8673669 DOI: 10.1371/journal.ppat.1010140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/23/2021] [Indexed: 11/19/2022] Open
Abstract
Schistosomes infect over 200 million of the world's poorest people, but unfortunately treatment relies on a single drug. Nuclear hormone receptors are ligand-activated transcription factors that regulate diverse processes in metazoans, yet few have been functionally characterized in schistosomes. During a systematic analysis of nuclear receptor function, we found that an FTZ-F1-like receptor was essential for parasite survival. Using a combination of transcriptional profiling and chromatin immunoprecipitation (ChIP), we discovered that the micro-exon gene meg-8.3 is a transcriptional target of SmFTZ-F1. We found that both Smftz-f1 and meg-8.3 are required for esophageal gland maintenance as well as integrity of the worm's head. Together, these studies define a new role for micro-exon gene function in the parasite and suggest that factors associated with the esophageal gland could represent viable therapeutic targets.
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Affiliation(s)
- Aracely A. Romero
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Sarah A. Cobb
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Julie N. R. Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - Steven A. Kliewer
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, Texas, United States of America
| | - David J. Mangelsdorf
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
- Howard Hughes Medical Institute, Dallas, Texas, United States of America
| | - James J. Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas, United States of America
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Amaral MS, Santos DW, Pereira ASA, Tahira AC, Malvezzi JVM, Miyasato PA, Freitas RDP, Kalil J, Tjon Kon Fat EM, de Dood CJ, Corstjens PLAM, van Dam GJ, Nakano E, Castro SDO, Mattaraia VGDM, Augusto RDC, Grunau C, Wilson RA, Verjovski-Almeida S. Rhesus macaques self-curing from a schistosome infection can display complete immunity to challenge. Nat Commun 2021; 12:6181. [PMID: 34702841 PMCID: PMC8548296 DOI: 10.1038/s41467-021-26497-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 10/05/2021] [Indexed: 12/13/2022] Open
Abstract
The rhesus macaque provides a unique model of acquired immunity against schistosomes, which afflict >200 million people worldwide. By monitoring bloodstream levels of parasite-gut-derived antigen, we show that from week 10 onwards an established infection with Schistosoma mansoni is cleared in an exponential manner, eliciting resistance to reinfection. Secondary challenge at week 42 demonstrates that protection is strong in all animals and complete in some. Antibody profiles suggest that antigens mediating protection are the released products of developing schistosomula. In culture they are killed by addition of rhesus plasma, collected from week 8 post-infection onwards, and even more efficiently with post-challenge plasma. Furthermore, cultured schistosomula lose chromatin activating marks at the transcription start site of genes related to worm development and show decreased expression of genes related to lysosomes and lytic vacuoles involved with autophagy. Overall, our results indicate that enhanced antibody responses against the challenge migrating larvae mediate the naturally acquired protective immunity and will inform the route to an effective vaccine. To date there is only one single drug with modest efficacy and no vaccine available to protect from schistosomiasis. Here, Amaral et al. characterize the self-cure process of rhesus macaques following primary infection and secondary challenge with Schistosoma mansoni to inform future vaccine development studies.
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Affiliation(s)
| | - Daisy Woellner Santos
- Laboratório de Parasitologia, Instituto Butantan, Sao Paulo, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Adriana S A Pereira
- Laboratório de Parasitologia, Instituto Butantan, Sao Paulo, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de Sao Paulo, Sao Paulo, Brazil
| | | | | | | | | | - Jorge Kalil
- Heart Institute, Faculty of Medicine, University of Sao Paulo (USP), Sao Paulo, Brazil
| | - Elisa M Tjon Kon Fat
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Claudia J de Dood
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Paul L A M Corstjens
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - Govert J van Dam
- Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands
| | - Eliana Nakano
- Laboratório de Parasitologia, Instituto Butantan, Sao Paulo, Brazil
| | | | | | - Ronaldo de Carvalho Augusto
- LBMC, Laboratoire de Biologie et Modélisation de la Cellule Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, UMR 5239, INSERM, U1210, Lyon, France.,IHPE, Univ. Perpignan Via Domitia, CNRS, IFREMER, Univ Montpellier, Perpignan, France
| | - Christoph Grunau
- IHPE, Univ. Perpignan Via Domitia, CNRS, IFREMER, Univ Montpellier, Perpignan, France
| | - R Alan Wilson
- York Biomedical Research Institute, Department of Biology, University of York, Heslington, York, United Kingdom
| | - Sergio Verjovski-Almeida
- Laboratório de Parasitologia, Instituto Butantan, Sao Paulo, Brazil. .,Departamento de Bioquímica, Instituto de Química, Universidade de Sao Paulo, Sao Paulo, Brazil.
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10
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Wendt GR, Reese ML, Collins JJ. SchistoCyte Atlas: A Single-Cell Transcriptome Resource for Adult Schistosomes. Trends Parasitol 2021; 37:585-587. [PMID: 33975779 DOI: 10.1016/j.pt.2021.04.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 10/21/2022]
Abstract
Schistosomes cause untold disease and disability in the developing world. Here, we introduce SchistoCyte Atlas, a web-based platform for exploring gene expression at single-cell resolution in adult Schistosoma mansoni. Similar resources accessible to non-specialists across the globe will expedite our ability to understand the biology of these devastating parasites.
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Affiliation(s)
- George R Wendt
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Michael L Reese
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, USA; Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - James J Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, USA.
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11
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Vlaminck J, Lagatie O, Dana D, Mekonnen Z, Geldhof P, Levecke B, Stuyver LJ. Identification of antigenic linear peptides in the soil-transmitted helminth and Schistosoma mansoni proteome. PLoS Negl Trop Dis 2021; 15:e0009369. [PMID: 33909616 PMCID: PMC8081252 DOI: 10.1371/journal.pntd.0009369] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/07/2021] [Indexed: 11/18/2022] Open
Abstract
The scientific community identified non stool-based biomarkers as the way forward to support soil-transmitted helminth (STH; Ascaris lumbricoides, Trichuris trichiura and the hookworms Ancylostoma duodenale and Necator americanus) and schistosome (S. mansoni and S. haematobium) deworming programs. This support is needed in making the decision of whether or not to stop preventive chemotherapy intervention efforts and to ultimately transition towards a post-intervention surveillance phase. We applied a two-step micro-array approach to identify antigenic linear epitopes in the STH and S. mansoni proteomes. In a first experiment, we identified antigenic peptides by applying sera from 24 STH and/or S. mansoni infected Ethiopian children on a high-density peptide microarray containing 3.3 million peptides derived from the complete STH and S. mansoni proteomes. A second array experiment with 170,185 peptides that were recognized in the first array was designed to identify non-specific antibody reactivity by applying sera from 24 healthy individuals from Belgium (a non-endemic country). From this array testing cascade, several peptides were identified for STH but none of them appeared to be unique for one species. We therefore concluded that for STH, none of the peptides revealed to be sufficiently sensitive or species specific. For S. mansoni, some promising peptides were identified prompting future investigation. Based on these results, it is unlikely that linear epitopes would be highly useful in detecting species-specific antibody responses to STH in endemic communities. For S. mansoni, one particular peptide of the micro-exon gene 12 (MEG-12) protein deserves further research. In addition, this study emphasizes the need of well-characterized biobanks for biomarker discovery, particularly when the integration of multiple disease programs is envisioned. Today, infections with intestinal (roundworms, whipworm and hookworms) and blood-dwelling worms (schistosomes) are traditionally diagnosed by demonstrating worm eggs in stool. This current practice comes with some important challenges, including but not limited to the low-throughput and the need of skilled operators. Especially in the context of monitoring and evaluation, there is a need for alternative tools. Therefore, one of the recommendations of the scientific community was to develop tests that are based on the detection of antibodies in blood, which reflect the natural immune response of the host to worm-specific components or antigens. In the present study, we screened the antigenicity of all the peptides that build up the proteome of intestinal and blood-dwelling worms. For intestinal worms, our results revealed that the antibody response to these peptides was either not unique for the worm species or absent in infected subjects. For blood-dwelling worms, the findings were less sobering, with a number of peptides inducing an antibody response that was only observed in infected subjects.
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Affiliation(s)
- Johnny Vlaminck
- Department of Virology, Parasitology, Immunology and Physiology, Ghent University, Merelbeke, Belgium
| | - Ole Lagatie
- Global Public Health R&D, Janssen Pharmaceutica NV, Beerse, Belgium
- * E-mail:
| | - Daniel Dana
- Department of Virology, Parasitology, Immunology and Physiology, Ghent University, Merelbeke, Belgium
- School of Laboratory Science, Faculty of health science, Institute of health, Jimma University, Jimma, Ethiopia
| | - Zeleke Mekonnen
- School of Laboratory Science, Faculty of health science, Institute of health, Jimma University, Jimma, Ethiopia
| | - Peter Geldhof
- Department of Virology, Parasitology, Immunology and Physiology, Ghent University, Merelbeke, Belgium
| | - Bruno Levecke
- Department of Virology, Parasitology, Immunology and Physiology, Ghent University, Merelbeke, Belgium
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12
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Nanes Sarfati D, Li P, Tarashansky AJ, Wang B. Single-cell deconstruction of stem-cell-driven schistosome development. Trends Parasitol 2021; 37:790-802. [PMID: 33893056 DOI: 10.1016/j.pt.2021.03.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 02/07/2023]
Abstract
Schistosomes cause one of the most devastating neglected tropical diseases, schistosomiasis. Their transmission is accomplished through a complex life cycle with two obligate hosts and requires multiple radically different body plans specialized for infecting and reproducing in each host. Recent single-cell transcriptomic studies on several schistosome body plans provide a comprehensive map of their cell types, which include stem cells and their differentiated progeny along an intricate developmental hierarchy. This progress not only extends our understanding of the basic biology of the schistosome life cycle but can also inform new therapeutic and preventive strategies against the disease, as blocking the development of specific cell types through genetic manipulations has shown promise in inhibiting parasite survival, growth, and reproduction.
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Affiliation(s)
| | - Pengyang Li
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | | | - Bo Wang
- Department of Bioengineering, Stanford University, Stanford, CA, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA.
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Farias LP, Vance GM, Coulson PS, Vitoriano-Souza J, Neto APDS, Wangwiwatsin A, Neves LX, Castro-Borges W, McNicholas S, Wilson KS, Leite LCC, Wilson RA. Epitope Mapping of Exposed Tegument and Alimentary Tract Proteins Identifies Putative Antigenic Targets of the Attenuated Schistosome Vaccine. Front Immunol 2021; 11:624613. [PMID: 33763055 PMCID: PMC7982949 DOI: 10.3389/fimmu.2020.624613] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/14/2020] [Indexed: 02/03/2023] Open
Abstract
The radiation-attenuated cercarial vaccine remains the gold standard for the induction of protective immunity against Schistosoma mansoni. Furthermore, the protection can be passively transferred to naïve recipient mice from multiply vaccinated donors, especially IFNgR KO mice. We have used such sera versus day 28 infection serum, to screen peptide arrays and identify likely epitopes that mediate the protection. The arrays encompassed 55 secreted or exposed proteins from the alimentary tract and tegument, the principal interfaces with the host bloodstream. The proteins were printed onto glass slides as overlapping 15mer peptides, reacted with primary and secondary antibodies, and reactive regions detected using an Agilent array scanner. Pep Slide Analyzer software provided a numerical value above background for each peptide from which an aggregate score could be derived for a putative epitope. The reactive regions of 26 proteins were mapped onto crystal structures using the CCP4 molecular graphics, to aid selection of peptides with the greatest accessibility and reactivity, prioritizing vaccine over infection serum. A further eight MEG proteins were mapped to regions conserved between family members. The result is a list of priority peptides from 44 proteins for further investigation in multiepitope vaccine constructs and as targets of monoclonal antibodies.
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Affiliation(s)
- Leonardo P. Farias
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
| | - Gillian M. Vance
- York Biomedical Research Institute, University of York, York, United Kingdom
| | - Patricia S. Coulson
- York Biomedical Research Institute, University of York, York, United Kingdom
| | | | - Almiro Pires da Silva Neto
- Laboratório de Inflamação e Biomarcadores, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Brazil
| | - Arporn Wangwiwatsin
- Parasite Genomics, Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Leandro Xavier Neves
- Instituto de Ciẽncias Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | - William Castro-Borges
- Instituto de Ciẽncias Exatas e Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | - Stuart McNicholas
- York Structural Biology Laboratory, University of York, York, United Kingdom
| | - Keith S. Wilson
- York Structural Biology Laboratory, University of York, York, United Kingdom
| | - Luciana C. C. Leite
- Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
| | - R. Alan Wilson
- York Biomedical Research Institute, University of York, York, United Kingdom
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Schistosoma mansoni alter transcription of immunomodulatory gene products following in vivo praziquantel exposure. PLoS Negl Trop Dis 2021; 15:e0009200. [PMID: 33657133 PMCID: PMC7959349 DOI: 10.1371/journal.pntd.0009200] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/15/2021] [Accepted: 02/02/2021] [Indexed: 12/12/2022] Open
Abstract
Control of the neglected tropical disease schistosomiasis relies almost entirely on praziquantel (PZQ) monotherapy. How PZQ clears parasite infections remains poorly understood. Many studies have examined the effects of PZQ on worms cultured in vitro, observing outcomes such as muscle contraction. However, conditions worms are exposed to in vivo may vary considerably from in vitro experiments given the short half-life of PZQ and the importance of host immune system engagement for drug efficacy in animal models. Here, we investigated the effects of in vivo PZQ exposure on Schistosoma mansoni. Measurement of pro-apoptotic caspase activation revealed that worm death occurs only after parasites shift from the mesenteric vasculature to the liver, peaking 24 hours after drug treatment. This indicates that PZQ is not directly schistocidal, since PZQ’s half-life is ~2 hours in humans and ~30 minutes in mice, and focuses attention on parasite interactions with the host immune system following the shift of worms to the liver. RNA-Seq of worms harvested from mouse livers following sub-lethal PZQ treatment revealed drug-evoked changes in the expression of putative immunomodulatory and anticoagulant gene products. Several of these gene products localized to the schistosome esophagus and may be secreted into the host circulation. These include several Kunitz-type protease inhibitors, which are also found in the secretomes of other blood feeding animals. These transcriptional changes may reflect mechanisms of parasite immune-evasion in response to chemotherapy, given the role of complement-mediated attack and the host innate/humoral immune response in parasite elimination. One of these isoforms, SmKI-1, has been shown to exhibit immunomodulatory and anti-coagulant properties. These data provide insight into the effect of in vivo PZQ exposure on S. mansoni, and the transcriptional response of parasites to the stress of chemotherapy. The disease schistosomiasis is caused by parasitic worms that live within the circulatory system. While this disease infects over 200 million people worldwide, treatment relies almost entirely on one drug, praziquantel, whose mechanism is poorly understood. In this study, we analyzed the effects of praziquantel treatment on the gene expression of parasites harvested from mice treated with praziquantel chemotherapy. Despite the rapid action of the drug on worms in vitro, we found that key outcomes in vivo (measurement of cell death and changes in gene expression) occurred relatively late (12+ hours after drug administration). We found that worms increased the expression of immunomodulatory gene products in response to praziquantel, including a Kunitz-type protease inhibitor that localized to the worm esophagus and may be secreted to the external host environment. These are an intriguing class of proteins, because they display anti-coagulant and immunomodulatory properties. Up-regulation of these gene products may reflect a parasite mechanism of immune-evasion in response to chemotherapy. This research provides insight into the mechanism of praziquantel by observing the effect of this drug on worms within the context of the host immune system.
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15
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Diaz Soria CL, Lee J, Chong T, Coghlan A, Tracey A, Young MD, Andrews T, Hall C, Ng BL, Rawlinson K, Doyle SR, Leonard S, Lu Z, Bennett HM, Rinaldi G, Newmark PA, Berriman M. Single-cell atlas of the first intra-mammalian developmental stage of the human parasite Schistosoma mansoni. Nat Commun 2020; 11:6411. [PMID: 33339816 PMCID: PMC7749135 DOI: 10.1038/s41467-020-20092-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/13/2020] [Indexed: 12/21/2022] Open
Abstract
Over 250 million people suffer from schistosomiasis, a tropical disease caused by parasitic flatworms known as schistosomes. Humans become infected by free-swimming, water-borne larvae, which penetrate the skin. The earliest intra-mammalian stage, called the schistosomulum, undergoes a series of developmental transitions. These changes are critical for the parasite to adapt to its new environment as it navigates through host tissues to reach its niche, where it will grow to reproductive maturity. Unravelling the mechanisms that drive intra-mammalian development requires knowledge of the spatial organisation and transcriptional dynamics of different cell types that comprise the schistomulum body. To fill these important knowledge gaps, we perform single-cell RNA sequencing on two-day old schistosomula of Schistosoma mansoni. We identify likely gene expression profiles for muscle, nervous system, tegument, oesophageal gland, parenchymal/primordial gut cells, and stem cells. In addition, we validate cell markers for all these clusters by in situ hybridisation in schistosomula and adult parasites. Taken together, this study provides a comprehensive cell-type atlas for the early intra-mammalian stage of this devastating metazoan parasite.
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Affiliation(s)
| | - Jayhun Lee
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, USA
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Tracy Chong
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, USA
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Avril Coghlan
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Alan Tracey
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Matthew D Young
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Tallulah Andrews
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Christopher Hall
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Bee Ling Ng
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Kate Rawlinson
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Stephen R Doyle
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Steven Leonard
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Zhigang Lu
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Hayley M Bennett
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK
| | - Gabriel Rinaldi
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK.
| | - Phillip A Newmark
- Regenerative Biology, Morgridge Institute for Research, Madison, WI, USA.
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA.
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, USA.
| | - Matthew Berriman
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, UK.
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16
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Schistosoma mansoni venom allergen-like protein 6 (SmVAL6) maintains tegumental barrier function. Int J Parasitol 2020; 51:251-261. [PMID: 33253697 PMCID: PMC7957364 DOI: 10.1016/j.ijpara.2020.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/17/2020] [Accepted: 09/22/2020] [Indexed: 11/23/2022]
Abstract
Smval6 is expressed in oral/ventral suckers, oesophageal gland and mesenchymal cells of Schistosoma mansoni. Smval6 knockdown increases surface membrane permeability. SmVAL6 interacts with Sm14 and DLC proteins.
The Schistosoma mansoni venom allergen-like protein (SmVAL) superfamily is a collection of at least 29 molecules that have been classified into two distinctive groups (Group 1 and Group 2 SmVALs). The fundamental basis for SmVAL segregation relates to signal peptide and conserved cysteine retention (present in all Group 1 SmVALs, but absent in all Group 2 SmVALs). These structural differences have led to the hypothesis that most Group 1 SmVALs, found as components of schistosome excretory/secretory (E/S) products, predominantly interact with their environment (intermediate or definitive hosts) whereas the Group 2 SmVALs are retained within the schistosome to fulfil parasite-related functions. While experimental evidence to support Group 1 SmVAL/host interactions is growing, similar support for identification of parasite-related Group 2 SmVAL functions is currently lacking. By applying a combination of approaches to the study of SmVAL6, we provide the first known evidence for an essential function of a Group 2 SmVAL in schistosome biology. After whole mount in situ hybridisation (WISH) localised Smval6 to the anterior region of the oesophageal gland (AOG) and cells scattered through the mesenchyme in adult schistosomes, short interfering RNA (siRNA)-mediated silencing of Smval6 was employed to assess loss of function phenotypes. Here, siSmval6-mediated knockdown of transcript and protein levels led to an increase in tegumental permeability as assessed by the quantification of TAMRA-labelled dextran throughout sub-tegumental cells/tissues. Yeast two hybrid screening using SmVAL6 as a bait revealed Sm14 (a fatty acid binding protein) and a dynein light chain (DLC) as directly interacting partners. Interrogation of single-cell RNA-seq (scRNA-seq) data supported these protein interactions by demonstrating the spatial co-expression of Smval6/dlc/Sm14 in a small proportion of adult cell types (e.g. neurons, tegumental cells and neoblasts). In silico modelling of SmVAL6 with Sm14 and DLC provided evidence that opposing faces of SmVAL6 were likely responsible for these protein/protein interactions. Our results suggest that SmVAL6 participates in oesophageal biology, formation of higher order protein complexes and maintenance of tegumental barrier function. Further studies of other Group 2 SmVALs may reveal additional functions of this enigmatic superfamily.
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Lee J, Chong T, Newmark PA. The esophageal gland mediates host immune evasion by the human parasite Schistosoma mansoni. Proc Natl Acad Sci U S A 2020; 117:19299-19309. [PMID: 32737161 PMCID: PMC7431036 DOI: 10.1073/pnas.2006553117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Schistosomes are parasitic flatworms that cause schistosomiasis, a neglected tropical disease affecting over 200 million people. Schistosomes develop multiple body plans while navigating their complex life cycle, which involves two different hosts: a mammalian definitive host and a molluscan intermediate host. Their survival and propagation depend upon proliferation and differentiation of stem cells necessary for parasite homeostasis and reproduction. Infective larvae released from snails carry a handful of stem cells that serve as the likely source of new tissues as the parasite adapts to life inside the mammalian host; however, the role of these stem cells during this critical life cycle stage remains unclear. Here, we characterize stem cell fates during early intramammalian development. Surprisingly, we find that the esophageal gland, an accessory organ of the digestive tract, develops before the rest of the digestive system is formed and blood feeding is initiated, suggesting a role in processes beyond nutrient uptake. To explore such a role, we examine schistosomes that lack the esophageal gland due to knockdown of a forkhead-box transcription factor, Sm-foxA, which blocks development and maintenance of the esophageal gland, without affecting the development of other somatic tissues. Intriguingly, schistosomes lacking the esophageal gland die after transplantation into naive mice, but survive in immunodeficient mice lacking B cells. We show that parasites lacking the esophageal gland are unable to lyse ingested immune cells within the esophagus before passing them into the gut. These results unveil an immune-evasion mechanism mediated by the esophageal gland, which is essential for schistosome survival and pathogenesis.
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Affiliation(s)
- Jayhun Lee
- Regenerative Biology, Morgridge Institute for Research, Madison, WI 53715
| | - Tracy Chong
- Regenerative Biology, Morgridge Institute for Research, Madison, WI 53715
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI 53715
| | - Phillip A Newmark
- Regenerative Biology, Morgridge Institute for Research, Madison, WI 53715;
- Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI 53715
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI 53715
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Wangwiwatsin A, Protasio AV, Wilson S, Owusu C, Holroyd NE, Sanders MJ, Keane J, Doenhoff MJ, Rinaldi G, Berriman M. Transcriptome of the parasitic flatworm Schistosoma mansoni during intra-mammalian development. PLoS Negl Trop Dis 2020; 14:e0007743. [PMID: 32374726 PMCID: PMC7263636 DOI: 10.1371/journal.pntd.0007743] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 06/01/2020] [Accepted: 02/27/2020] [Indexed: 12/11/2022] Open
Abstract
Schistosomes are parasitic blood flukes that survive for many years within the mammalian host vasculature. How the parasites establish a chronic infection in the hostile bloodstream environment, whilst evading the host immune response is poorly understood. The parasite develops morphologically and grows as it migrates to its preferred vascular niche, avoiding or repairing damage from the host immune system. In this study, we investigated temporal changes in gene expression during the intra-mammalian development of Schistosoma mansoni. RNA-seq data were analysed from parasites developing in the lung through to egg-laying mature adult worms, providing a comprehensive picture of in vivo intra-mammalian development. Remarkably, genes involved in signalling pathways, developmental control, and adaptation to oxidative stress were up-regulated in the lung stage. The data also suggested a potential role in immune evasion for a previously uncharacterised gene. This study not only provides a large and comprehensive data resource for the research community, but also reveals new directions for further characterising host-parasite interactions that could ultimately lead to new control strategies for this neglected tropical disease pathogen.
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Affiliation(s)
- Arporn Wangwiwatsin
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
- Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen, Thailand
| | - Anna V. Protasio
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
- Department of Pathology, Tennis Court Road, University of Cambridge, Cambridge, United Kingdom
| | - Shona Wilson
- Department of Pathology, Tennis Court Road, University of Cambridge, Cambridge, United Kingdom
| | - Christian Owusu
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Nancy E. Holroyd
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Mandy J. Sanders
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Jacqueline Keane
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Mike J. Doenhoff
- School of Life Sciences, University of Nottingham, University Park, Nottingham, United Kingdom
| | - Gabriel Rinaldi
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Matthew Berriman
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
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Felizatti AP, Zeraik AE, Basso LG, Kumagai PS, Lopes JL, Wallace B, Araujo AP, DeMarco R. Interactions of amphipathic α-helical MEG proteins from Schistosoma mansoni with membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183173. [DOI: 10.1016/j.bbamem.2019.183173] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 02/04/2023]
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Li XH, Vance GM, Cartwright J, Cao JP, Wilson RA, Castro-Borges W. Mapping the epitopes of Schistosoma japonicum esophageal gland proteins for incorporation into vaccine constructs. PLoS One 2020; 15:e0229542. [PMID: 32107503 PMCID: PMC7046203 DOI: 10.1371/journal.pone.0229542] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 02/07/2020] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The development of a schistosome vaccine has proved challenging but we have suggested that characterisation of the self-cure mechanism in rhesus macaques might provide a route to an effective product. The schistosome esophagus is a complex structure where blood processing is initiated by secretions from anterior and posterior glands, achieved by a mixture of ~40 unique proteins. The mechanism of self-cure in macaques involves cessation of feeding, after which worms slowly starve to death. Antibody coats the esophagus lumen and disrupts the secretory processes from the glands, potentially making their secretions ideal vaccine targets. METHODOLOGY/PRINCIPAL FINDINGS We have designed three peptide arrays comprising overlapping 15-mer peptides encompassing 32 esophageal gland proteins, and screened them for reactivity against 22-week infection serum from macaques versus permissive rabbit and mouse hosts. There was considerable intra- and inter-species variation in response and no obvious unique target was associated with self-cure status, which suggests that self-cure is achieved by antibodies reacting with multiple targets. Some immuno-dominant sequences/regions were evident across species, notably including: MEGs 4.1C, 4.2, and 11 (Array 1); MEG-12 and Aspartyl protease (Array 2); a Tetraspanin 1 loop and MEG-n2 (Array 3). Responses to MEGs 8.1C and 8.2C were largely confined to macaques. As proof of principle, three synthetic genes were designed, comprising several key targets from each array. One of these was expressed as a recombinant protein and used to vaccinate rabbits. Higher antibody titres were obtained to the majority of reactive regions than those elicited after prolonged infection. CONCLUSIONS/SIGNIFICANCE It is feasible to test simultaneously the additive potential of multiple esophageal proteins to induce protection by combining their most reactive regions in artificial constructs that can be used to vaccinate suitable hosts. The efficacy of the approach to disrupt esophageal function now needs to be tested by a parasite challenge.
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Affiliation(s)
- Xiao-Hong Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People’s Republic of China
| | - Gillian M. Vance
- Centre for Immunology and Infection, Department of Biology, University of York, York, England, United Kingdom
| | - Jared Cartwright
- Protein Production Laboratory, Department of Biology, University of York, York, England, United Kingdom
| | - Jian-Ping Cao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People’s Republic of China
| | - R Alan Wilson
- Centre for Immunology and Infection, Department of Biology, University of York, York, England, United Kingdom
| | - William Castro-Borges
- Departamento de Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brasil
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21
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Neves LX, Wilson RA, Brownridge P, Harman VM, Holman SW, Beynon RJ, Eyers CE, DeMarco R, Castro-Borges W. Quantitative Proteomics of Enriched Esophageal and Gut Tissues from the Human Blood Fluke Schistosoma mansoni Pinpoints Secreted Proteins for Vaccine Development. J Proteome Res 2019; 19:314-326. [PMID: 31729880 DOI: 10.1021/acs.jproteome.9b00531] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Schistosomes are blood-dwelling helminth parasites that cause schistosomiasis, a debilitating disease resulting in inflammation and, in extreme cases, multiple organ damage. Major challenges to control the transmission persist, and the discovery of protective antigens remains of critical importance for vaccine development. Rhesus macaques can self-cure following schistosome infection, generating antibodies that target proteins from the tegument, gut, and esophagus, the last of which is the least investigated. We developed a dissection technique that permitted increased sensitivity in a comparative proteomics profiling of schistosome esophagus and gut. Proteome analysis of the male schistosome esophagus identified 13 proteins encoded by microexon genes (MEGs), 11 of which were uniquely located in the esophageal glands. Based on this and transcriptome information, a QconCAT was designed for the absolute quantification of selected targets. MEGs 12, 4.2, and 4.1 and venom allergen-like protein 7 were the most abundant, spanning over 245 million to 6 million copies per cell, while aspartyl protease, palmitoyl thioesterase, and galactosyl transferase were present at <1 million copies. Antigenic variation by alternative splicing of MEG proteins was confirmed together with a specialized machinery for protein glycosylation/secretion in the esophagus. Moreover, some gastrodermal secretions were highly enriched in the gut, while others were more uniformly distributed throughout the parasite, potentially indicating lysosomal activity. Collectively, our findings provide a more rational, better-oriented selection of schistosome vaccine candidates in the context of a proven model of protective immunity.
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Affiliation(s)
- Leandro X Neves
- Departamento de Ciências Biológicas , Universidade Federal de Ouro Preto , Campus Morro do Cruzeiro , Ouro Preto 35400-000 , Minas Gerais , Brazil
| | - R Alan Wilson
- Centre for Immunology and Infection, Department of Biology , University of York , Heslington, York YO10 5DD , United Kingdom
| | - Philip Brownridge
- Centre for Proteome Research, Department of Biochemistry, Institute of Integrative Biology , University of Liverpool , Liverpool L69 7ZB , United Kingdom
| | - Victoria M Harman
- Centre for Proteome Research, Department of Biochemistry, Institute of Integrative Biology , University of Liverpool , Liverpool L69 7ZB , United Kingdom
| | - Stephen W Holman
- Centre for Proteome Research, Department of Biochemistry, Institute of Integrative Biology , University of Liverpool , Liverpool L69 7ZB , United Kingdom
| | - Robert J Beynon
- Centre for Proteome Research, Department of Biochemistry, Institute of Integrative Biology , University of Liverpool , Liverpool L69 7ZB , United Kingdom
| | - Claire E Eyers
- Centre for Proteome Research, Department of Biochemistry, Institute of Integrative Biology , University of Liverpool , Liverpool L69 7ZB , United Kingdom
| | - Ricardo DeMarco
- Instituto de Física de São Carlos , Universidade de São Paulo , São Carlos 13566-590 , Brazil
| | - William Castro-Borges
- Departamento de Ciências Biológicas , Universidade Federal de Ouro Preto , Campus Morro do Cruzeiro , Ouro Preto 35400-000 , Minas Gerais , Brazil
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22
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Lu Z, Spänig S, Weth O, Grevelding CG. Males, the Wrongly Neglected Partners of the Biologically Unprecedented Male-Female Interaction of Schistosomes. Front Genet 2019; 10:796. [PMID: 31552097 PMCID: PMC6743411 DOI: 10.3389/fgene.2019.00796] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/30/2019] [Indexed: 01/18/2023] Open
Abstract
Schistosomes are the only platyhelminths that have evolved separate sexes, and they exhibit a unique reproductive biology because the female’s sexual maturation depends on a constant pairing contact with the male. In the female, pairing leads to gonad differentiation, which is associated with substantial morphological changes, and controls among others the expression of gonad-associated genes. In the male, no morphological changes have been observed after pairing, although first data indicated an effect of pairing on gene transcription. Comprehensive transcriptomic approaches have revealed an unexpected high number of genes that are differentially transcribed in the male after pairing. Their identities suggest roles for the male that are not restricted to feeding and enhanced muscular power to transport paired female and, as assumed before, to induce its sexual maturation by one “magic” factor. Instead, a more complex picture emerges in which both partners live in a reciprocal sender-recipient relationship that not only affects the gonads of both genders but may also involve tactile stimuli, transforming growth factor β signaling, nutritional parts, and neuronal processes, including neuropeptides and G protein-coupled receptor signaling. This review provides a summary of transcriptomics including an overview of genes expressed in a pairing-dependent manner in schistosome males. This may stimulate further research in understanding the role of the male as the recipient of the female’s signals upon pairing, the male’s “capacitation,” and its subsequent competence as a sender of information. The latter process finally transforms a sexually immature, autonomous female without completely developed gonads into a sexually mature, partially non-autonomous female with fully differentiated gonads and enormous egg production capacity.
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Affiliation(s)
- Zhigang Lu
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom.,Insitute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
| | - Sebastian Spänig
- Department of Mathematics & Computer Science, University of Marburg, Marburg, Germany
| | - Oliver Weth
- Insitute for Parasitology, BFS, Justus Liebig University Giessen, Giessen, Germany
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Brandão-Bezerra L, de Carvalho Martins JSC, de Oliveira RMF, Lopes-Torres EJ, Neves RH, Corrêa CL, Machado-Silva JR. Long-term ethanol intake causes morphological changes in Schistosoma mansoni adult worms in mice. Exp Parasitol 2019; 203:30-35. [PMID: 31150655 DOI: 10.1016/j.exppara.2019.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 05/03/2019] [Accepted: 05/27/2019] [Indexed: 12/18/2022]
Abstract
Schistosoma mansoni adult worms are extensively challenged by reactive oxygen species from intrinsic sources. However, the effects of extrinsic sources such as ethanol have not been looked at in schistosomes. We examined adult worms recovered from ethanol-consuming mice by light (LM), confocal (CM) and scanning electron microscopy (SEM) to address this question. Schistosomiasis-infected mice were orally gavaged with 18% (v/v) ethanol from 35 to 63 days post-infection, when they were euthanized. CM examination revealed reduced germ cells density (-36%, p = 0.0001) and sperm density (-58%, p = 0.0001) in testicular lobes, and immature cells in seminal vesicle compared to unexposed control worms. Female worms showed reduced density of vitellin glands (-71%, p = 0.0001), maturation of oocytes (-7%, p = 0.0071) and reduced spermatozoa density (-23%, p = 0.0002) within the seminal receptacle. SEM revealed remarkable damages in male's tegument, including tubercles flattening, tegumental peeling and erosive lesions. Given that lipids are present in reproductive system and tegument, our results suggest that phenotypic changes are due to ethanol-induced lipid peroxidation. To the best of our knowledge, this is the first report revealing the biological action of ethanol intake on adult schistosomes in vivo.
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Affiliation(s)
- Luciana Brandão-Bezerra
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Jéssica Santa Cruz de Carvalho Martins
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Regina Maria Figueiredo de Oliveira
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Eduardo José Lopes-Torres
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Renata Heisler Neves
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Christiane Leal Corrêa
- Department of Pathology and Laboratories, School of Medical Sciences, Rio de Janeiro State University, Brazil; Medicine School, Estácio de Sá University, Brazil
| | - José Roberto Machado-Silva
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil.
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Molecular evidence for distinct modes of nutrient acquisition between visceral and neurotropic schistosomes of birds. Sci Rep 2019; 9:1347. [PMID: 30718911 PMCID: PMC6362228 DOI: 10.1038/s41598-018-37669-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 12/10/2018] [Indexed: 12/19/2022] Open
Abstract
Trichobilharzia species are parasitic flatworms (called schistosomes or flukes) that cause important diseases in birds and humans, but very little is known about their molecular biology. Here, using a transcriptomics-bioinformatics-based approach, we explored molecular aspects pertaining to the nutritional requirements of Trichobilharzia szidati (‘visceral fluke’) and T. regenti (‘neurotropic fluke’) in their avian host. We studied the larvae of each species before they enter (cercariae) and as they migrate (schistosomules) through distinct tissues in their avian (duck) host. Cercariae of both species were enriched for pathways or molecules associated predominantly with carbohydrate metabolism, oxidative phosphorylation and translation of proteins linked to ribosome biogenesis, exosome production and/or lipid biogenesis. Schistosomules of both species were enriched for pathways or molecules associated with processes including signal transduction, cell turnover and motility, DNA replication and repair, molecular transport and/or catabolism. Comparative informatic analyses identified molecular repertoires (within, e.g., peptidases and secretory proteins) in schistosomules that can broadly degrade macromolecules in both T. szidati and T. regenti, and others that are tailored to each species to selectively acquire nutrients from particular tissues through which it migrates. Thus, this study provides molecular evidence for distinct modes of nutrient acquisition between the visceral and neurotropic flukes of birds.
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Cosenza-Contreras M, de Oliveira E Castro RA, Mattei B, Campos JM, Gonçalves Silva G, de Paiva NCN, de Oliveira Aguiar-Soares RD, Carneiro CM, Afonso LCC, Castro-Borges W. The Schistosomiasis SpleenOME: Unveiling the Proteomic Landscape of Splenomegaly Using Label-Free Mass Spectrometry. Front Immunol 2019; 9:3137. [PMID: 30728824 PMCID: PMC6352917 DOI: 10.3389/fimmu.2018.03137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 12/19/2018] [Indexed: 01/17/2023] Open
Abstract
Schistosomiasis is a neglected parasitic disease that affects millions of people worldwide and is caused by helminth parasites from the genus Schistosoma. When caused by S. mansoni, it is associated with the development of a hepatosplenic disease caused by an intense immune response to the important antigenic contribution of adult worms and to the presence of eggs trapped in liver tissue. Although the importance of the spleen for the establishment of immune pathology is widely accepted, it has received little attention in terms of the molecular mechanisms operating in response to the infection. Here, we interrogated the spleen proteome using a label-free shotgun approach for the potential discovery of molecular mechanisms associated to the peak of the acute phase of inflammation and the development of splenomegaly in the murine model. Over fifteen hundred proteins were identified in both infected and control individuals and 325 of those proteins were differentially expressed. Two hundred and forty-two proteins were found upregulated in infected individuals while 83 were downregulated. Functional enrichment analyses for differentially expressed proteins showed that most of them were categorized within pathways of innate and adaptive immunity, DNA replication, vesicle transport and catabolic metabolism. There was an important contribution of granulocyte proteins and antigen processing and presentation pathways were augmented, with the increased expression of MHC class II molecules but the negative regulation of cysteine and serine proteases. Several proteins related to RNA processing were upregulated, including splicing factors. We also found indications of metabolic reprogramming in spleen cells with downregulation of proteins related to mitochondrial metabolism. Ex-vivo imunophenotyping of spleen cells allowed us to attribute the higher abundance of MHC II detected by mass spectrometry to increased number of macrophages (F4/80+/MHC II+ cells) in the infected condition. We believe these findings add novel insights for the understanding of the immune mechanisms associated with the establishment of schistosomiasis and the processes of immune modulation implied in the host-parasite interactions.
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Affiliation(s)
- Miguel Cosenza-Contreras
- Programa de Pós Graduação em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | | | - Bruno Mattei
- Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | - Jonatan Marques Campos
- Programa de Pós Graduação em Biotecnologia, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | - Gustavo Gonçalves Silva
- Programa de Pós Graduação em Biotecnologia, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | | | | | | | - Luis Carlos Crocco Afonso
- Departamento de Ciências Biológicas, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
| | - William Castro-Borges
- Departamento de Ciências Biológicas, Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Brazil
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Form and Function in the Digenea. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1154:3-20. [DOI: 10.1007/978-3-030-18616-6_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Diagnosis of schistosomiasis mansoni: an evaluation of existing methods and research towards single worm pair detection. Parasitology 2018; 145:1355-1366. [PMID: 29506583 DOI: 10.1017/s0031182018000240] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The inadequacy of current diagnostics for the detection of low worm burdens in humans means that schistosomiasis mansoni is more widespread than previously acknowledged. With the inception of mass drug treatment programmes aimed at disease elimination and the advent of human vaccine trials, the need for more sensitive diagnostics is evident. In this review, we evaluate the merits and limitations of the principal diagnostic methods, namely detection of eggs in faeces; anti-schistosome antibodies in serum; parasite-derived proteins and glycans in serum or urine; parasite DNA in blood, faeces or urine. Only in the baboon model, where actual worm burden is determined by portal perfusion, have faecal smear and circulating antigen methods been calibrated, and shown to have thresholds of detection of 10-19 worm pairs. There is scope for improvement in all the four methods of detection, e.g. the identification of single targets for host antibodies to improve the specificity of enzyme linked immunosorbent assay. Despite recent advances in the definition of the schistosome secretome, there have been no comprehensive biomarker investigations of parasite products in the urine of infected patients. Certainly, the admirable goal of eliminating schistosomiasis will not be achieved unless individuals with low worm burdens can be diagnosed.
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Li XH, DeMarco R, Neves LX, James SR, Newling K, Ashton PD, Cao JP, Wilson RA, Castro-Borges W. Microexon gene transcriptional profiles and evolution provide insights into blood processing by the Schistosoma japonicum esophagus. PLoS Negl Trop Dis 2018; 12:e0006235. [PMID: 29432451 PMCID: PMC5825161 DOI: 10.1371/journal.pntd.0006235] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/23/2018] [Accepted: 01/12/2018] [Indexed: 02/06/2023] Open
Abstract
Background Adult schistosomes have a well-developed alimentary tract comprising an oral sucker around the mouth, a short esophagus and a blind ending gut. The esophagus is not simply a muscular tube for conducting blood from the mouth to gut but is divided into compartments, surrounded by anterior and posterior glands, where processing of ingested blood is initiated. Self-cure of rhesus macaques from a Schistosoma japonicum infection appears to operate by blocking the secretory functions of these glands so that the worms cease feeding and slowly starve to death. Here we use subtractive RNASeq to characterise the genes encoding the principal secretory products of S. japonicum esophageal glands, preparatory to evaluating their relevance as targets of the self-cure process. Methodology/Principal findings The heads and a small portion of the rear end of male and female S. japonicum worms were separately enriched by microdissection, for mRNA isolation and library construction. The sequence reads were then assembled de novo using Trinity and those genes enriched more than eightfold in the head preparation were subjected to detailed bioinformatics analysis. Of the 62 genes selected from the male heads, more than one third comprised MEGs encoding secreted or membrane-anchored proteins. Database searching using conserved motifs revealed that the MEG-4 and MEG-8/9 families had counterparts in the bird schistosome Trichobilharzia regenti, indicating an ancient association with blood processing. A second group of MEGs, including a MEG-26 family, encoded short peptides with amphipathic properties that most likely interact with ingested host cell membranes to destabilise them. A number of lysosomal hydrolases, two protease inhibitors, a secreted VAL and a putative natterin complete the line-up. There was surprisingly little difference between expression patterns in males and females despite the latter processing much more blood. Significance/Conclusions The mixture of approximately 40 proteins specifically secreted by the esophageal glands is responsible for initiating blood processing in the adult worm esophagus. They comprise the potential targets for the self-cure process in the rhesus macaque, and thus represent a completely new cohort of secreted proteins that can be investigated as vaccine candidates. Schistosomes are parasitic flatworms inhabiting the human bloodstream, surrounded by and feeding on humoral and cellular components of the immune system. They are normally long-lived but the rhesus macaque is able to mount a self-cure response directed against the esophageal secretions of the adult Schistosoma japonicum so that they stop feeding and slowly starve to death. The worm esophagus is a short tube connecting mouth to gut surrounded by anterior and posterior glands and our aim in this study was to identify the genes encoding the gland secretions. For this purpose we isolated the messenger RNA from both male and female worm heads and tails and obtained many millions of sequences. These were assembled into gene coding sequences using bioinformatics and then genes differentially expressed in the head region were identified by a subtraction process. We then focused on those genes encoding proteins with a leader sequence indicating their secretory status. The result is an inventory of approximately 40 genes; some encode protein binding motifs while others encode a short helix with a hydrophobic face, which may interact with host cell membranes. Genes encoding enzymes, protease inhibitors and a venom-like protein were also found. These proteins are being evaluated for their interactions with the antibodies generated by macaques during the self-cure process.
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Affiliation(s)
- Xiao-Hong Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People’s Republic of China
| | - Ricardo DeMarco
- Instituto de Física de São Carlos, Universidade de São Paulo, Sao Carlos, Brasil
| | - Leandro X. Neves
- Departamento de Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brasil
| | - Sally R. James
- Genomics and Bioinformatics Laboratory, Department of Biology, University of York, York, United Kingdom
| | - Katherine Newling
- Genomics and Bioinformatics Laboratory, Department of Biology, University of York, York, United Kingdom
| | - Peter D. Ashton
- Genomics and Bioinformatics Laboratory, Department of Biology, University of York, York, United Kingdom
| | - Jian-Ping Cao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People’s Republic of China
| | - R. Alan Wilson
- Centre for Immunology and Infection, Department of Biology, University of York, York, United Kingdom
- * E-mail:
| | - William Castro-Borges
- Departamento de Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brasil
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Schistosome vaccines: problems, pitfalls and prospects. Emerg Top Life Sci 2017; 1:641-650. [PMID: 33525844 DOI: 10.1042/etls20170094] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 11/21/2017] [Accepted: 11/22/2017] [Indexed: 12/14/2022]
Abstract
Human schistosomiasis caused by parasitic flatworms of the genus Schistosoma remains an important public health problem in spite of concerted efforts at control. An effective vaccine would be a useful addition to control strategies that currently rely on chemotherapy, but such a product is not imminent. In this review, likely causes for the lack of progress are first considered. These include the strategies used by worms to evade the immune response, concepts that have misdirected the field, an emphasis on internal antigens, and the use of the laboratory mouse for vaccine testing. On a positive note, recent investigations on self-cure by the rhesus macaque offer the most promising context for vaccine development. The identification of proteins at the parasite-host interface, especially those of the esophageal glands involved in blood processing, has provided an entirely new category of vaccine candidates that merit evaluation.
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Lengerer B, Wunderer J, Pjeta R, Carta G, Kao D, Aboobaker A, Beisel C, Berezikov E, Salvenmoser W, Ladurner P. Organ specific gene expression in the regenerating tail of Macrostomum lignano. Dev Biol 2017; 433:448-460. [PMID: 28757111 DOI: 10.1016/j.ydbio.2017.07.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 07/21/2017] [Accepted: 07/27/2017] [Indexed: 11/25/2022]
Abstract
Temporal and spatial characterization of gene expression is a prerequisite for the understanding of cell-, tissue-, and organ-differentiation. In a multifaceted approach to investigate gene expression in the tail plate of the free-living marine flatworm Macrostomum lignano, we performed a posterior-region-specific in situ hybridization screen, RNA sequencing (RNA-seq) of regenerating animals, and functional analyses of selected tail-specific genes. The in situ screen revealed transcripts expressed in the antrum, cement glands, adhesive organs, prostate glands, rhabdite glands, and other tissues. Next we used RNA-seq to characterize temporal expression in the regenerating tail plate revealing a time restricted onset of both adhesive organs and copulatory apparatus regeneration. In addition, we identified three novel previously unannotated genes solely expressed in the regenerating stylet. RNA interference showed that these genes are required for the formation of not only the stylet but the whole male copulatory apparatus. RNAi treated animals lacked the stylet, vesicula granulorum, seminal vesicle, false seminal vesicle, and prostate glands, while the other tissues of the tail plate, such as adhesive organs regenerated normally. In summary, our findings provide a large resource of expression data during homeostasis and regeneration of the morphologically complex tail regeneration and pave the way for a better understanding of organogenesis in M. lignano.
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Affiliation(s)
- Birgit Lengerer
- Institute of Zoology and Center of Molecular Bioscience Innsbruck, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
| | - Julia Wunderer
- Institute of Zoology and Center of Molecular Bioscience Innsbruck, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
| | - Robert Pjeta
- Institute of Zoology and Center of Molecular Bioscience Innsbruck, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
| | - Giada Carta
- Division of Physiology, Medical University of Innsbruck, Schöpfstraße 41/EG, A-6020 Innsbruck, Austria.
| | - Damian Kao
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, United Kingdom.
| | - Aziz Aboobaker
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, United Kingdom.
| | - Christian Beisel
- Department of Biosystems Science and Engineering, ETH Zürich, Mattenstrasse 26, 4058 Basel, Switzerland.
| | - Eugene Berezikov
- European Research Institute for the Biology of Ageing, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, NL-9713 AV Groningen, The Netherlands.
| | - Willi Salvenmoser
- Institute of Zoology and Center of Molecular Bioscience Innsbruck, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
| | - Peter Ladurner
- Institute of Zoology and Center of Molecular Bioscience Innsbruck, University of Innsbruck, Technikerstr. 25, A-6020 Innsbruck, Austria.
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Fernandes RS, Barbosa TC, Barbosa MMF, Miyasato PA, Nakano E, Leite LCC, Farias LP. Stage and tissue expression patterns of Schistosoma mansoni venom allergen-like proteins SmVAL 4, 13, 16 and 24. Parasit Vectors 2017; 10:223. [PMID: 28482920 PMCID: PMC5422958 DOI: 10.1186/s13071-017-2144-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/19/2017] [Indexed: 11/20/2022] Open
Abstract
Background Schistosoma mansoni venom allergen-like protein (SmVAL) is a gene family composed of 29 members divided into group 1 encoding proteins potentially secreted, and group 2 encoding intracellular components. Some members were found to be upregulated in the transition of germ ball - cercariae - day 3 schistosomula, suggesting that group 1 SmVAL proteins are associated with the invasion of the human host, although their functions are not completely established. Recently, we have described the localization of SmVAL7 (group 1) and SmVAL6 (group 2) transcripts in the oesophageal gland and in the oral and ventral suckers of adult parasites, respectively. The expression patterns of the two genes suggest that SmVAL7 protein plays a role in the blood-feeding process while SmVAL6 is associated with the parasite attachment and movement in the vasculature. In this way, searching for additional secreted SmVAL proteins that could be involved in key processes from skin penetration to the beginning of blood-feeding, we investigated the tissue localization of SmVAL4, 13, 16 and 24 by whole-mount in situ hybridization (WISH). Results We report here the localization of group 1 SmVAL4 and 24 transcripts in the pre-acetabular glands of developing germ balls. Time course experiments of in vitro cultured schistosomula after cercariae transformation demonstrated that SmVAL4 protein is secreted during the first 3 h of in vitro culture, correlating with the emptying of acetabular glands as documented by confocal microscopy. In addition, the localization of SmVAL13 transcripts in adult male anterior oesophageal gland suggests that the respective protein may be involved in the first steps of the blood-feeding process. SmVAL16 was localized close to the neural ganglia and requires further investigation. Conclusions Our findings demonstrate that SmVAL proteins have localizations that place them in strategic positions to be considered as potential vaccine candidates as some members are exposed to interaction with the immune system and may participate in key processes of mammalian invasion and parasitism establishment. Electronic supplementary material The online version of this article (doi:10.1186/s13071-017-2144-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rafaela Sachetto Fernandes
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo, SP, Brazil.,Programa de Pós-Graduação Interunidades em Biotecnologia, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Mayra Mara Ferrari Barbosa
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo, SP, Brazil.,Programa de Pós-Graduação Interunidades em Biotecnologia, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Patrícia Aoki Miyasato
- Laboratório de Parasitologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo, SP, Brazil
| | - Eliana Nakano
- Laboratório de Parasitologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo, SP, Brazil
| | | | - Leonardo Paiva Farias
- Centro de Biotecnologia, Instituto Butantan, Av. Vital Brasil, 1500, São Paulo, SP, Brazil. .,Present Address: Instituto Gonçalo Moniz, Fundação Oswaldo Cruz (FIOCRUZ), Salvador, BA, Brazil.
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Protasio AV, van Dongen S, Collins J, Quintais L, Ribeiro DM, Sessler F, Hunt M, Rinaldi G, Collins JJ, Enright AJ, Berriman M. MiR-277/4989 regulate transcriptional landscape during juvenile to adult transition in the parasitic helminth Schistosoma mansoni. PLoS Negl Trop Dis 2017; 11:e0005559. [PMID: 28542189 PMCID: PMC5459504 DOI: 10.1371/journal.pntd.0005559] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/05/2017] [Accepted: 04/05/2017] [Indexed: 01/06/2023] Open
Abstract
Schistosomes are parasitic helminths that cause schistosomiasis, a disease affecting circa 200 million people, primarily in underprivileged regions of the world. Schistosoma mansoni is the most experimentally tractable schistosome species due to its ease of propagation in the laboratory and the high quality of its genome assembly and annotation. Although there is growing interest in microRNAs (miRNAs) in trematodes, little is known about the role these molecules play in the context of developmental processes. We use the completely unaware "miRNA-blind" bioinformatics tool Sylamer to analyse the 3'-UTRs of transcripts differentially expressed between the juvenile and adult stages. We show that the miR-277/4989 family target sequence is the only one significantly enriched in the transition from juvenile to adult worms. Further, we describe a novel miRNA, sma-miR-4989 showing that its proximal genomic location to sma-miR-277 suggests that they form a miRNA cluster, and we propose hairpin folds for both miRNAs compatible with the miRNA pathway. In addition, we found that expression of sma-miR-277/4989 miRNAs are up-regulated in adults while their predicted targets are characterised by significant down-regulation in paired adult worms but remain largely undisturbed in immature "virgin" females. Finally, we show that sma-miR-4989 is expressed in tegumental cells located proximal to the oesophagus gland and also distributed throughout the male worms' body. Our results indicate that sma-miR-277/4989 might play a dominant role in post-transcriptional regulation during development of juvenile worms and suggest an important role in the sexual development of female schistosomes.
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Affiliation(s)
- Anna V. Protasio
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Stijn van Dongen
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Julie Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, United States of America
| | - Leonor Quintais
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Diogo M. Ribeiro
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Florian Sessler
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Martin Hunt
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Gabriel Rinaldi
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - James J. Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX, United States of America
| | - Anton J. Enright
- European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Matthew Berriman
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
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Yang YYM, Li XH, Brzezicka K, Reichardt NC, Wilson RA, van Diepen A, Hokke CH. Specific anti-glycan antibodies are sustained during and after parasite clearance in Schistosoma japonicum-infected rhesus macaques. PLoS Negl Trop Dis 2017; 11:e0005339. [PMID: 28151933 PMCID: PMC5308859 DOI: 10.1371/journal.pntd.0005339] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 02/14/2017] [Accepted: 01/18/2017] [Indexed: 12/20/2022] Open
Abstract
Background Human immunity to Schistosoma infection requires many years of exposure, and multiple infections and treatments to develop. Unlike humans, rhesus macaques clear an established schistosome infection naturally at the same time acquiring immunity towards re-infection. In macaques, schistosome egg production decreases after 8 weeks post-infection and by week 22, physiological impairment of the worm caused by unclarified antibody-mediated processes is observed. Since strong antibody responses have been observed against schistosome glycan antigens in human and animal infections, we here investigate if anti-glycan antibodies are associated with immunity against schistosome infections in macaques. Methods We used a microarray containing a large repertoire of glycoprotein- and glycolipid-derived glycans from different schistosome life stages to analyse anti-glycan serum IgG and IgM from S. japonicum-infected macaques during the course of infection and self-cure. We also used an in vitro schistosomula assay to investigate whether macaque sera containing anti-glycan antibodies can kill schistosomula. Conclusions/significance Antibody responses towards schistosome glycans at week 4 post-infection were dominated by IgM while IgG was high at week 8. The profound increase in IgG was observed mainly for antibodies towards a large subset of glycans that contain (multi-)fucosylated terminal GalNAcβ1-4GlcNAc (LDN), and Galβ1-4(Fucα1–3)GlcNAc (LeX) motifs. In general, glycans with a higher degree of fucosylation gave rise to stronger antibody responses than non-fucosylated glycans. Interestingly, even though many IgG and IgM responses had declined by week 22 post-infection, IgG towards O-glycans with highly fucosylated LDN motifs remained. When incubating macaque serum with schistosomula in vitro, schistosomula death was positively correlated with the duration of infection of macaques; macaque serum taken 22 weeks post-infection caused most schistosomula to die, suggesting the presence of potentially protective antibodies. We hypothesize that IgGs against highly fucosylated LDN motifs that remain when the worms deteriorate are associated with infection clearance and the resistance to re-infection in macaques. Schistosomes express many glycan antigens to which antibodies are raised by the infected host. These glycans may therefore form potential vaccine targets. Unlike humans where the disease persists chronically if not treated, schistosome-infected rhesus macaques are able to elicit a self-cure process naturally. To find out if anti-glycan responses could contribute to the natural clearance process, we followed the dynamics of anti-glycan serum antibodies in Schistosoma-infected macaques in a longitudinal study starting from the onset of infection until 22 weeks post-infection, when the macaques had eliminated most of the parasites. We found that sera of macaques taken after 22 weeks of infection contained high IgG titres towards specific schistosome glycan epitopes highly abundant on schistosome larvae. Moreover, infected macaque serum at week 22 was able to kill schistosomula in vitro. Our results suggest that anti-glycan antibodies play an important role in the self-cure process and the acquired resistance to re-infection in Schistosoma infected macaques.
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Affiliation(s)
- Y. Y. Michelle Yang
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Xiao Hong Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, and Key Laboratory of Parasitology and Vector Biology, Ministry of Health, Shanghai, China
| | | | | | - R. Alan Wilson
- Centre for Immunology & Infection, Department of Biology, University of York, York, United Kingdom
| | - Angela van Diepen
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
| | - Cornelis H. Hokke
- Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands
- * E-mail:
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Xiao SH, Sun J. Schistosoma hemozoin and its possible roles. Int J Parasitol 2016; 47:171-183. [PMID: 28012717 DOI: 10.1016/j.ijpara.2016.10.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 12/20/2022]
Abstract
More than 95years ago Schistosoma pigment had been deemed as a degradation product of haemoglobin. Until the 1950s, scientists initiated to pay attention to understand the hematophagous habit of schistosomes, and to study the degradation of haemoglobin as well as the formation of hemozoin inside the gut of the worms. For a long time, the formation of hemozoin in both Plasmodium and in Schistosoma was considered to be the major route of heme detoxification, and hemozoin served a role in waste disposal. At the beginning of this century, the chemical structure of Schistosoma pigment was confirmed to be identical to that of malarial pigment (hemozoin) and its synthetic analogue, β-hematin. Since then, studies on Schistosoma hemozoin have been investigated by some workers and the results showed that Schistosoma hemozoin may play important roles in pathogenicity, immune modulation, iron supply for egg formation, and interaction with some anti-schistosomal drugs. In this review, we briefly review and discuss the hematophagous habit of schistosomes, degradation of haemoglobin, formation of hemozoin in the worm gut, and possible roles of hemozoin.
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Affiliation(s)
- Shu-Hua Xiao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, MOH, WHO Collaborating Centre for Malaria, Schistosomiasis, and Filariasis, Shanghai 200025, China.
| | - Jun Sun
- Institute for Infectious Disease and Vaccine Development, Tongji University School of Medicine, Shanghai 200092, China.
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Collins JNR, Collins JJ. Tissue Degeneration following Loss of Schistosoma mansoni cbp1 Is Associated with Increased Stem Cell Proliferation and Parasite Death In Vivo. PLoS Pathog 2016; 12:e1005963. [PMID: 27812220 PMCID: PMC5094730 DOI: 10.1371/journal.ppat.1005963] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 09/29/2016] [Indexed: 01/06/2023] Open
Abstract
Schistosomiasis is second only to malaria in terms of the global impact among diseases caused by parasites. A striking feature of schistosomes are their ability to thrive in their hosts for decades. We have previously demonstrated that stem cells, called neoblasts, promote homeostatic tissue maintenance in adult schistosomes and suggested these cells likely contribute to parasite longevity. Whether these schistosome neoblasts have functions independent of homeostatic tissue maintenance, for example in processes such as tissue regeneration following injury, remains unexplored. Here we characterize the schistosome CBP/p300 homolog, Sm-cbp1. We found that depleting cbp1 transcript levels with RNA interference (RNAi) resulted in increased neoblast proliferation and cell death, eventually leading to organ degeneration. Based on these observations we speculated this increased rate of neoblast proliferation may be a response to mitigate tissue damage due to increased cell death. Therefore, we tested if mechanical injury was sufficient to stimulate neoblast proliferation. We found that mechanical injury induced both cell death and neoblast proliferation at wound sites, suggesting that schistosome neoblasts are capable of mounting proliferative responses to injury. Furthermore, we observed that the health of cbp1(RNAi) parasites progressively declined during the course of our in vitro experiments. To determine the fate of cbp1(RNAi) parasites in the context of a mammalian host, we coupled RNAi with an established technique to transplant schistosomes into the mesenteric veins of uninfected mice. We found transplanted cbp1(RNAi) parasites were cleared from vasculature of recipient mice and were incapable of inducing measurable pathology in their recipient hosts. Together our data suggest that injury is sufficient to induce neoblast proliferation and that cbp1 is essential for parasite survival in vivo. These studies present a new methodology to study schistosome gene function in vivo and highlight a potential role for schistosome neoblasts in promoting tissue repair following injury.
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Affiliation(s)
| | - James J. Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, Texas
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Tebeje BM, Harvie M, You H, Loukas A, McManus DP. Schistosomiasis vaccines: where do we stand? Parasit Vectors 2016; 9:528. [PMID: 27716365 PMCID: PMC5045607 DOI: 10.1186/s13071-016-1799-4] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/14/2016] [Indexed: 12/20/2022] Open
Abstract
Schistosomiasis, caused mainly by S. mansoni, S. haematobium and S. japonicum, continues to be a serious tropical disease and public health problem resulting in an unacceptably high level of morbidity in countries where it is endemic. Praziquantel, the only drug currently available for treatment, is unable to kill developing schistosomes, it does not prevent re-infection and its continued extensive use may result in the future emergence of drug-resistant parasites. This scenario provides impetus for the development and deployment of anti-schistosome vaccines to be used as part of an integrated approach for the prevention, control and eventual elimination of schistosomiasis. This review considers the present status of candidate vaccines for schistosomiasis, and provides some insight on future vaccine discovery and design.
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Affiliation(s)
- Biniam Mathewos Tebeje
- QIMR Berghofer Medical Research Institute, Brisbane, Australia. .,School of Public Health, University of Queensland, Brisbane, Australia. .,Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
| | - Marina Harvie
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Hong You
- QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Alex Loukas
- Centre for Biodiscovery and Molecular Development of Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Australia
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Interaction of an esophageal MEG protein from schistosomes with a human S100 protein involved in inflammatory response. Biochim Biophys Acta Gen Subj 2016; 1861:3490-3497. [PMID: 27639541 DOI: 10.1016/j.bbagen.2016.09.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 08/09/2016] [Accepted: 09/01/2016] [Indexed: 11/24/2022]
Abstract
BACKGROUND The Micro-Exon Gene-14 (MEG-14) displays a remarkable structure that allows the generation of antigenic variation in Schistosomes. Previous studies showed that the soluble portion of the MEG-14 protein displays features of an intrinsically disordered protein and is expressed exclusively in the parasite esophageal gland. These features indicated a potential for interaction with host proteins present in the plasma and cells from ingested blood. METHODS A yeast two-hybrid experiment using as bait the soluble domain of Schistosoma mansoni MEG-14 (sMEG-14) against a human leukocyte cDNA library was performed. Pull-down and surface plasmon resonance (SPR) experiments were used to validate the interaction between sMEG-14 and human S100A9. Synchrotron radiation circular dichroism (SRCD) were used to detect structural changes upon interaction between sMEG-14 and human S100A9. Feeding of live parasites with S100A9 attached to a fluorophore allowed the tracking of the fate of this protein in the parasite digestive system. RESULTS S100A9 interacted with sMEG-14 consistently in yeast two-hybrid assay, pull-down and SPR experiments. SRCD suggested that MEG-14 acquired a more regular structure as a result of the interaction with S100A9. Accumulation of recombinant S100A9 in the parasite's esophageal gland, when ingested by live worms suggests that such interaction may occur in vivo. CONCLUSION S100A9, a protein previously described to be involved in modulation of inflammatory response, was found to interact with sMEG-14. GENERAL SIGNIFICANCE Our results allow proposing a mechanism involving MEG-14 for the parasite to block inflammatory signaling, which would occur upon release of S100A9 when ingested blood cells are lysed.
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Wang J, Collins JJ. Identification of new markers for the Schistosoma mansoni vitelline lineage. Int J Parasitol 2016; 46:405-10. [PMID: 27056273 PMCID: PMC4917872 DOI: 10.1016/j.ijpara.2016.03.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 03/21/2016] [Accepted: 03/23/2016] [Indexed: 11/23/2022]
Abstract
Transcriptional profiling identifies candidate factors associated with the schistosome vitellarium. In situ hybridization confirms many new markers of this tissue. New cell type-specific markers for various stages of vitellocyte development are reported.
Schistosomes cause significant morbidity and mortality in millions of the world’s poorest people. While parasite egg-induced inflammation is the primary driver of host pathology, relatively little is known at the molecular level about the organ systems that participate in schistosome egg production (i.e., testes, ovaries and vitellaria). Here we use transcriptional profiling and in situ hybridization to characterise the vitellarium of Schistosoma mansoni. We uncovered several previously uncharacterised vitellaria-specific factors and defined molecular markers for various stages in the vitellocyte differentiation process. These data provide the framework for future in-depth molecular studies exploring the biology of this important parasite organ.
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Affiliation(s)
- Jipeng Wang
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - James J Collins
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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