1
|
Reamtong O, Simanon N, Thiangtrongjit T, Limpanont Y, Chusongsang P, Chusongsang Y, Anuntakarun S, Payungporn S, Phuphisut O, Adisakwattana P. Proteomic analysis of adult Schistosoma mekongi somatic and excretory-secretory proteins. Acta Trop 2020; 202:105247. [PMID: 31672487 DOI: 10.1016/j.actatropica.2019.105247] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 07/30/2019] [Accepted: 10/25/2019] [Indexed: 12/19/2022]
Abstract
Schistosoma mekongi is a causative agent of human schistosomiasis. There is limited knowledge of the molecular biology of S. mekongi and very few studies have examined drug targets, vaccine candidates and diagnostic biomarkers for S. mekongi. To explore the biology of S. mekongi, computational as well as experimental approaches were performed on S. mekongi males and females to identify excretory-secretory (ES) proteins and proteins that are differentially expressed between genders. According to bioinformatic prediction, the S. mekongi ES product was approximately 4.7% of total annotated transcriptome sequences. The classical secretory pathway was the main process to secrete proteins. Mass spectrometry-based quantification of male and female adult S. mekongi proteins was performed. We identified 174 and 156 differential expression of proteins in male and female worms, respectively. The dominant male-biased proteins were involved in actin filament-based processes, microtubule-based processes, biosynthetic processes and homeostatic processes. The major female-biased proteins were related to biosynthetic processes, organelle organization and signal transduction. An experimental approach identified 88 proteins in the S. mekongi secretome. The S. mekongi ES proteins mainly contributed to nutrient uptake, essential substance supply and host immune evasion. This research identifies proteins in the S. mekongi secretome and provides information on ES proteins that are differentially expressed between S. mekongi genders. These findings will contribute to S. mekongi drug and vaccine development. In addition, the study enhances our understanding of basic S. mekongi biology.
Collapse
|
2
|
Non-immune immunoglobulins shield Schistosoma japonicum from host immunorecognition. Sci Rep 2015; 5:13434. [PMID: 26299686 PMCID: PMC4547136 DOI: 10.1038/srep13434] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 07/27/2015] [Indexed: 11/18/2022] Open
Abstract
Schistosomiasis is a major human parasitic disease with a global impact. Schistosoma japonicum, the most difficult to control, can survive within host veins for decades. Mechanisms of immune evasion by the parasite, including antigenic variation and surface masking, have been implicated but not well defined. In this study, we defined the immunoglobulin-binding proteomes of S. japonicum using human IgG, IgM, and IgE as the molecular bait for affinity purification, followed by protein identification by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Several proteins situated at the tegument of S. japonicum were able to nonselectively bind to the Fc domain of host immunoglobulins, indicating a mechanism for the avoidance of host immune attachment and recognition. The profile of the immunoglobulin-binding proteomes provides further clues for immune evasion mechanisms adopted by S. japonicum.
Collapse
|
3
|
Specific humoral response of hosts with variable schistosomiasis susceptibility. Immunol Cell Biol 2015; 94:52-65. [PMID: 26044065 DOI: 10.1038/icb.2015.61] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/11/2015] [Accepted: 05/29/2015] [Indexed: 01/08/2023]
Abstract
The schistosome blood flukes are some of the largest global causes of parasitic morbidity. Further study of the specific antibody response during schistosomiasis may yield the vaccines and diagnostics needed to combat this disease. Therefore, for the purposes of antigen discovery, sera and antibody-secreting cell (ASC) probes from semi-permissive rats and sera from susceptible mice were used to screen a schistosome protein microarray. Following Schistosoma japonicum infection, rats had reduced pathology, increased antibody responses and broader antigen recognition profiles compared with mice. With successive infections, rat global serological reactivity and the number of recognized antigens increased. The local antibody response in rat skin and lung, measured with ASC probes, increased after parasite migration and contributed antigen-specific antibodies to the multivalent serological response. In addition, the temporal variation of anti-parasite serum antibodies after infection and reinfection followed patterns that appear related to the antigen driving the response. Among the 29 antigens differentially recognized by the infected hosts were numerous known vaccine candidates, drug targets and several S. japonicum homologs of human schistosomiasis resistance markers-the tegument allergen-like proteins. From this set, we prioritized eight proteins that may prove to be novel schistosome vaccine and diagnostic antigens.
Collapse
|
4
|
Zhou XN, Bergquist R, Leonardo L, Yang GJ, Yang K, Sudomo M, Olveda R. Schistosomiasis japonica control and research needs. ADVANCES IN PARASITOLOGY 2010; 72:145-78. [PMID: 20624531 DOI: 10.1016/s0065-308x(10)72006-6] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Schistosomiasis japonica, a chronic and debilitating disease caused by the blood fluke Schistosoma japonicum, is still of considerable economic and public health concern in the People's Republic of China, the Philippines, and Indonesia. Despite major progress made over the past several decades with the control of schistosomiasis japonica in the aforementioned countries, the disease is emerging in some areas. We review the epidemiological status and transmission patterns of schistosomiasis japonica, placing it into a historical context, and discuss experiences and lessons with national control efforts. Our analyses reveal that an integrated control approach, implemented through intersectoral collaboration, is essential to bring down the prevalence and intensity of Schistosoma japonicum infections and disease-related morbidity, and to sustain these parameters at low levels. The need for innovation and a sufficiently flexible control approach to adapt interventions in response to the changing nature and challenges of schistosomiasis control from the initial phase of morbidity control to the final state of elimination is emphasised. The aim of the presentation and the analyses is to inspire researchers and disease control managers elsewhere in Asia, Africa, and the Americas to harness the experiences gained and the lessons presented here to improve the control and eventual elimination of schistosomiasis and parasitic diseases.
Collapse
Affiliation(s)
- Xiao-Nong Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
5
|
Romeih MH, Hassan HM, Shousha TSA, Saber MA. Immunization against Egyptian Schistosoma mansoni infection by multivalent DNA vaccine. Acta Biochim Biophys Sin (Shanghai) 2008; 40:327-38. [PMID: 18401531 DOI: 10.1111/j.1745-7270.2008.00404.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The development of multivalent vaccines consisting of several antigens is a novel approach to creating broad-range protection against different parasite strains and parasite life cycle stages. We have previously confirmed that the schistosome Sm21.7 and SmFimbrin (SmFim) proteins could induce protection in mice. Therefore, this study aimed to construct the multivalent DNA vaccine Sm21.7-SmFim/pBudCE4.1 and evaluate its immune efficacy. The open reading frames of two Schistosoma mansoni genes, Sm21.7 and SmFim, were inserted into the eukaryotic expression plasmid pBudCE4.1 designed for the independent expression of two genes in mammalian cells. To evaluate the in vitro expression of the multivalent Sm21.7-SmFim/pBudCE4.1 DNA vaccine and its immunological effect in mice, the recombinant plasmid Sm21.7-SmFim/pBudCE4.1 was used to transfect 293T cells, and the expression of mRNA and proteins was examined using reverse transcription-polymerase chain reaction and Western blot analysis. Then the ability of Sm21.7-SmFim/pBudCE4.1 to protect against S. mansoni challenge infections was analyzed according to worm burden and egg reduction rates after vaccination of mice. Vaccinated mice showed a significant level of protection (56%), and a decrease in the number and size, and change in the cellular profile, of granulomas. Egg reduction in liver and intestine was 41.53% and 55.63%, respectively, as determined relative to mice that received the empty vector only. In addition to reductions in worm viability, worm fecundity and egg hatching ability were observed following challenge infection in the immunized group. Results showed that Sm21.7-SmFim/pBudCE4.1 could express Sm21.7 and SmFim mRNA and proteins. Enzyme-linked immunosorbent assay and Western blot analysis indicated that immunized mice generated specific immunoglobulin G against Sm21.7-SmFim/pBudCE4.1. These results suggest that vaccination with multivalent S. mansoni DNA vaccine (SmFim-Sm21.7/pBudCE4.1) not only induces a significant reduction in worm and egg burdens, but also significantly reduces the size of egg granulomas. In summary, the multivalent vaccine stimulated specific immunity with a significant level of protection and has anti-pathological effect.
Collapse
Affiliation(s)
- Mahmoud H Romeih
- Department of Biochemistry and Molecular Biology, Theodor Bilharz Research Institute, Giza, Egypt.
| | | | | | | |
Collapse
|
6
|
Yu F, Kang B, Li Y, Li Y. Functional analysis of schistosomes EF-hand domain-containing tegument proteins. CHINESE SCIENCE BULLETIN-CHINESE 2007. [DOI: 10.1007/s11434-007-0312-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
7
|
Fitzsimmons CM, McBeath R, Joseph S, Jones FM, Walter K, Hoffmann KF, Kariuki HC, Mwatha JK, Kimani G, Kabatereine NB, Vennervald BJ, Ouma JH, Dunne DW. Factors Affecting Human IgE and IgG Responses to Allergen-Like Schistosoma mansoni Antigens: Molecular Structure and Patterns of in vivo Exposure. Int Arch Allergy Immunol 2006; 142:40-50. [PMID: 17019080 DOI: 10.1159/000095997] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Accepted: 07/27/2006] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The human IgE response is associated with allergy and with host defence against parasitic worms. A response to Sm22.6, the dominant IgE antigen in adult Schistosoma mansoni worms, correlates with resistance to re-infection after treatment. Sm22.6 is one of a family of EF-hand containing parasite proteins with sequence similarity to dynein light chain (DLC) and with major non-parasite allergens. Here we compare human IgE and IgG responses to other family members, Sm20.8 and Sm21.7, as well as to SmDLC1, relating these to antigen structure and expression in parasite life stages. METHODS Recombinant antigens were used in ELISA to measure antibody isotype responses in 177 cases from an endemic area, before and 7 weeks after treatment. Parasite antigen expression was assessed by RT-PCR and Western blotting. RESULTS Levels of antibodies to Sm22.6 and Sm20.8 (but not to Sm21.7 or SmDLC1) showed posttreatment increases in all but young children. Many produced IgE to Sm22.6 and Sm20.8 (2 EF-hands), few to Sm21.7 (1 EF-hand) or SmDLC1 (no EF-hands). Sm21.7 was expressed in cercariae, adults and eggs, Sm22.6 and Sm20.8 were concentrated in the adult. CONCLUSIONS These studies suggest that IgE antigens Sm22.6 and Sm20.8 are only released to boost antibodies when adult worms die, whilst Sm21.7 and SmDLC1 are released constantly from eggs dying in host tissue. IgE responses to these allergen-like molecules may be influenced by patterns of exposure and the number of EF-hand motifs.
Collapse
|
8
|
Wu HW, Hu XM, Wang Y, Kurtis JD, Zeng FJ, McGarvey ST, Wu GL, Zhang ZS, Hua ZC. Protective immunity induced by phage displayed mitochondrial related peptides of Schistosoma japonicum. Acta Trop 2006; 99:200-7. [PMID: 16999929 DOI: 10.1016/j.actatropica.2006.08.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2006] [Revised: 07/31/2006] [Accepted: 08/03/2006] [Indexed: 11/18/2022]
Abstract
New antigens and strategies are necessary for vaccine development against schistosomiasis japonica. Using a pool of 43 high titred anti-SWA sera from individuals residing in an Schistosoma japonicum endemic area of China, we have cloned a S. japonicum gene by cDNA library screening. The recombinant Sj338 protein has 44-46% identity to a mitochondrial precursor receptor protein of humans and rats. Immunization of mice with the recombinant Sj338 conferred 27-32% (p<0.01) reduction in worm burdens following cercarial challenge. In an effort to identify protective epitopes in Sj338 and increase the level of protection, we screened a random 12-mer peptide library constructed in M13 using a polyspecific anti-Sj338 rabbit serum. After five rounds of biopanning, we identified 30 reactive clones consisting of 11 distinct peptide sequences. These clones shared limited primary sequence homology with the recombinant Sj338 protein. Anti-sera raised against these phage clones recognized recombinant Sj338 and SWAP by Western blot. In murine vaccination experiments using whole recombinant phage without adjuvant, four of these clones demonstrated worm reductions of 11.6-25.1% (p=ns - 0.05) compared to M13 vaccinated animals. Animals vaccinated with all four of these phage demonstrated 34.2% (p<0.01) worm reduction compared to controls vaccinated with M13 clone. These data suggest that mimotope peptides are potential vaccine candidates for S. japonicum.
Collapse
Affiliation(s)
- Hai-Wei Wu
- Department of Pathogen Biology, Nanjing Medical University, 140 Hanzhong Rd, Nanjing, Jiangsu 210029, PR China.
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Liu F, Lu J, Hu W, Wang SY, Cui SJ, Chi M, Yan Q, Wang XR, Song HD, Xu XN, Wang JJ, Zhang XL, Zhang X, Wang ZQ, Xue CL, Brindley PJ, McManus DP, Yang PY, Feng Z, Chen Z, Han ZG. New perspectives on host-parasite interplay by comparative transcriptomic and proteomic analyses of Schistosoma japonicum. PLoS Pathog 2006; 2:e29. [PMID: 16617374 PMCID: PMC1435792 DOI: 10.1371/journal.ppat.0020029] [Citation(s) in RCA: 209] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Accepted: 03/06/2006] [Indexed: 11/20/2022] Open
Abstract
Schistosomiasis remains a serious public health problem with an estimated 200 million people infected in 76 countries. Here we isolated ~ 8,400 potential protein-encoding cDNA contigs from Schistosoma japonicum after sequencing circa 84,000 expressed sequence tags. In tandem, we undertook a high-throughput proteomics approach to characterize the protein expression profiles of a number of developmental stages (cercariae, hepatic schistosomula, female and male adults, eggs, and miracidia) and tissues at the host-parasite interface (eggshell and tegument) by interrogating the protein database deduced from the contigs. Comparative analysis of these transcriptomic and proteomic data, the latter including 3,260 proteins with putative identities, revealed differential expression of genes among the various developmental stages and sexes of S. japonicum and localization of putative secretory and membrane antigens, enzymes, and other gene products on the adult tegument and eggshell, many of which displayed genetic polymorphisms. Numerous S. japonicum genes exhibited high levels of identity with those of their mammalian hosts, whereas many others appeared to be conserved only across the genus Schistosoma or Phylum Platyhelminthes. These findings are expected to provide new insights into the pathophysiology of schistosomiasis and for the development of improved interventions for disease control and will facilitate a more fundamental understanding of schistosome biology, evolution, and the host-parasite interplay. Schistosomiasis remains a major public health problem in the developing world. Schistosoma japonicum, the Oriental blood fluke, causes intestinal schistosomiasis in China and the Philippines. Knowledge of the genome and proteome of this worm should improve understanding of biomedical aspects of schistosomiasis. This study represents the first major attempt to characterize the majority of the expressed genes and proteins of a human blood fluke through rigorous, high-throughput genomic and proteomic methodologies. The findings of this study provide a unique resource of numerous schistosome genes and information on protein profiles of the different developmental stages of S. japonicum. Many of the newly discovered proteins are localized on the surface of the worm and its eggs, and they are likely to be involved in the pathogenesis of schistosomiasis. Furthermore, genetic variants found in many of these new genes likely reflect the ability of this important human pathogen to adapt and respond to environmental pressures and the capacity of the parasite to respond to anti-schistosomal therapies. Comparison of these S. japonicum genes with those from mammals and other organisms will facilitate advances in the understanding of blood fluke biology and evolution.
Collapse
Affiliation(s)
- Feng Liu
- Chinese National Human Genome Center at Shanghai, Shanghai, China
- Proteomic Center and Department of Chemistry, Fudan University, Shanghai, China
| | - Jiong Lu
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Wei Hu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Sheng-Yue Wang
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Shu-Jian Cui
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Ming Chi
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Qing Yan
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Xin-Rong Wang
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Huai-Dong Song
- State Key Laboratory of Medical Genomics, Shanghai Second Medical University, Shanghai, China
| | - Xue-Nian Xu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Ju-Jun Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Xiang-Lin Zhang
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Xin Zhang
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Zhi-Qin Wang
- Chinese National Human Genome Center at Shanghai, Shanghai, China
| | - Chun-Liang Xue
- Department of Parasitology, Shanghai Second Medical University, Shanghai, China
| | - Paul J Brindley
- Department of Tropical Medicine, Tulane University Health Sciences Center, New Orleans, Louisiana, United States of America
| | - Donald P McManus
- Queensland Institute of Medical Research and Australian Center for International Health and Nutrition, Brisbane, Queensland, Australia
| | - Peng-Yuan Yang
- Proteomic Center and Department of Chemistry, Fudan University, Shanghai, China
| | - Zheng Feng
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai, China
| | - Zhu Chen
- Chinese National Human Genome Center at Shanghai, Shanghai, China
- State Key Laboratory of Medical Genomics, Shanghai Second Medical University, Shanghai, China
| | - Ze-Guang Han
- Chinese National Human Genome Center at Shanghai, Shanghai, China
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
10
|
Fitzsimmons CM, Stewart TJ, Hoffmann KF, Grogan JL, Yazdanbakhsh M, Dunne DW. Human IgE response to the Schistosoma haematobium 22.6 kDa antigen. Parasite Immunol 2004; 26:371-6. [PMID: 15679635 DOI: 10.1111/j.0141-9838.2004.00721.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In Schistosoma mansoni and S. japonicum infection, the 22.6 kDa tegumental antigens Sm22.6 and Sj22.6 are principal targets for the human IgE response, and levels of IgE to Sm22.6 have been correlated with resistance to re-infection after chemotherapy. S. haematobium is arguably a more important species in terms of human infection, and in this report we describe for the first time the molecular characterization of a cDNA from S. haematobium (Sh22.6) that is closely homologous to Sm22.6 and Sj22.6. As a member of the tegument-associated antigen family, Sh22.6 possesses EF-hand domains and regions homologous to the dynein light chain domains. We have expressed recombinant Sh22.6 and studied the IgE responses to the antigen in a group of 99 infected individuals (68 children and 31 adults) from an endemic area of Gabon who donated blood before and 5 weeks after praziquantel treatment. IgE to Sh22.6 was detected by ELISA in 18 subjects (18%), and in the majority of responders levels rose between pre- and post-treatment. Interestingly, the proportion of adults expressing IgE to Sh22.6 was 35.5%, significantly higher than the 10.3% seen in children. IgE from at least 10 of the 18 ELISA responders recognized Sh22.6 on Western blots of adult worm extract and recombinant antigen. These results demonstrate that like related molecules in other species, Sh22.6 is a target for the human IgE response. The data also indicate that changes in the IgE response occur with age or with progressive exposure to key antigens.
Collapse
Affiliation(s)
- C M Fitzsimmons
- Department of Pathology, University of Cambridge, Cambridge, UK.
| | | | | | | | | | | |
Collapse
|
11
|
Ross AG, Sleigh AC, Li Y, Davis GM, Williams GM, Jiang Z, Feng Z, McManus DP. Schistosomiasis in the People's Republic of China: prospects and challenges for the 21st century. Clin Microbiol Rev 2001; 14:270-95. [PMID: 11292639 PMCID: PMC88974 DOI: 10.1128/cmr.14.2.270-295.2001] [Citation(s) in RCA: 238] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Schistosomiasis japonica is a serious communicable disease and a major disease risk for more than 30 million people living in the tropical and subtropical zones of China. Infection remains a major public health concern despite 45 years of intensive control efforts. It is estimated that 865,000 people and 100,250 bovines are today infected in the provinces where the disease is endemic, and its transmission continues. Unlike the other schistosome species known to infect humans, the oriental schistosome, Schistosoma japonicum, is a true zoonotic organism, with a range of mammalian reservoirs, making control efforts extremely difficult. Clinical features of schistosomiasis range from fever, headache, and lethargy to severe fibro-obstructive pathology leading to portal hypertension, ascites, and hepatosplenomegaly, which can cause premature death. Infected children are stunted and have cognitive defects impairing memory and learning ability. Current control programs are heavily based on community chemotherapy with a single dose of the drug praziquantel, but vaccines (for use in bovines and humans) in combination with other control strategies are needed to make elimination of the disease possible. In this article, we provide an overview of the biology, epidemiology, clinical features, and prospects for control of oriental schistosomiasis in the People's Republic of China.
Collapse
Affiliation(s)
- A G Ross
- Australian Centre for International and Tropical Health and Nutrition, The Queensland Institute of Medical Research, and the University of Queensland, Brisbane, Queensland 4029, Australia
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Li Y, Auliff A, Jones MK, Yi X, McManus DP. Immunogenicity and immunolocalization of the 22.6 kDa antigen of Schistosoma japonicum. Parasite Immunol 2000; 22:415-24. [PMID: 10972848 DOI: 10.1046/j.1365-3024.2000.00319.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The 22.6 kDa tegumental-associated antigens of Schistosoma mansoni (Sm22.6) and Schistosoma japonicum (Sj22.6) are of recognized interest in schistosomiasis vaccine development, although no direct vaccination/challenge experiments using either Sm22.6 or Sj22.6 had been previously described. We report that Escherichia coli-expressed reSj22.6 failed to protect mice or water buffaloes against subsequent challenge with S. japonicum cercariae. This was despite the fact that specific IgG (buffaloes) and IgG and IgE (CBA mice) antibodies were generated against the 22.6 kDa molecule, observations consistent with some of our earlier findings. We could find no evidence from immunolocalization studies that Sj22.6 is expressed or exposed on the surface of the adult parasite since it appears to be restricted to the apical cytoplasm of the tegument and is not associated with the apical or basal membrane or any membrane-bound structures in the apical cytoplasm. Nevertheless, Sj22.6 must be released to the immune system during the course of infection because specific anti-Sj22.6 IgG antibodies were present in the sera of nonvaccinated but challenged mice. We conclude that it may be necessary to produce reSj22.6 in a more relevant expression system, such as baculovirus, to further establish its vaccine potential and that detailed immunochemical and immunolocalization studies of early developmental stages may be necessary to determine how Sj22.6 is released or shed in S. japonicum infections.
Collapse
Affiliation(s)
- Y Li
- Molecular Parasitology Unit, Tropical Health Program, Australian Centre for International and Tropical Health and Nutrition, The Queensland Institute of Medical Research and the University of Queensland, Australia
| | | | | | | | | |
Collapse
|
13
|
Ross AG, Sleigh AC, Li YS, Williams GM, Aligui GD, McManus DP. Is there immunity to Schistosoma japonicum? PARASITOLOGY TODAY (PERSONAL ED.) 2000; 16:159-64. [PMID: 10725903 DOI: 10.1016/s0169-4758(99)01621-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Oriental schistosome, Schistosoma japonicum, unlike the other two major schistosomes that infect humans (S. mansoni and S. haematobium), is a zoonotic species. The transmission dynamics and the potential effects of host-related regulatory factors, including immunity, are likely to be distinct for this parasite. Here, Allen Ross and collaborators from Australia, China and the Philippines discuss recently published and established epidemiological and laboratory data bearing on anti-infection immunity to Asian schistosomiasis, and contrast these findings with the emerging picture of development of anti-infection immunity against the African schistosomes. Implications for vaccines and other control strategies for schistosomiasis japonica are also discussed.
Collapse
Affiliation(s)
- A G Ross
- Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research and University of Queensland, Brisbane, Queensland, Australia
| | | | | | | | | | | |
Collapse
|
14
|
Hernandez MG, Hafalla JC, Acosta LP, Aligui FF, Aligui GD, Ramirez BL, Dunne DW, Santiago ML. Paramyosin is a major target of the human IgA response against Schistosoma japonicum. Parasite Immunol 1999; 21:641-7. [PMID: 10583866 DOI: 10.1046/j.1365-3024.1999.00263.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Human resistance and susceptibility to schistosomiasis is associated with age and specific antibody isotype responses against worm (SWAP) and egg (SEA) antigens. In a cross-sectional study of 176 individuals infected with Schistosoma japonicum in the Philippines, strikingly similar isotype response patterns against SWAP and SEA was observed when compared to other endemic areas. Interestingly, IgA titres to SWAP correlated with older age among S. japonicum-infected individuals (n = 176, P < 0.01), suggesting a role for this isotype in protective immunity. To identify the molecular targets of human IgA, 17 high-IgA/SWAP responders were identified from the said population. IgA antibodies from the majority (14/17) of these individuals recognized a band of 97 kDa (Sj97), comigrating in immunoblots with the myofibrillar protein paramyosin. The antigen was confirmed as paramyosin by expressed sequence tag (EST)-analysis of four clones obtained by screening an adult S. japonicum cDNA library with pooled IgA antisera and mouse antiparamyosin polyclonal antibodies. The identification of paramyosin as a major target of human IgA raises its potential as a vaccine candidate that targets mucosal immune responses. Since this antigen is exposed on the parasite surface only during the lung stages, we propose that human IgA contributes to parasite attrition during schistosome migration in the lungs.
Collapse
Affiliation(s)
- M G Hernandez
- Schistosomiasis Study Group, Research Institute for Tropical Medicine, Alabang, Muntinlupa City, Philippines
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
The search for an effective vaccine against schistosomiasis, a parasitic disease currently affecting over 200 million people, remains a desirable but as yet challenging and elusive goal. Progress in the area has been relatively slow but research demonstrating the ability of humans to acquire natural immunity to schistosome infection, together with the successful use in animals of attenuated vaccines, supplemented with encouraging results obtained with defined antigens, suggests that development of a vaccine is achievable. Noteworthy also are recent immune correlate findings which shed light on the complex, putatively protective immune responses in humans, which have improved the prospects of success. With the first human clinical trial having been completed with a schistosome vaccine candidate, this review examines current progress aimed at achieving the objective of a safe and effective vaccine for widespread use against schistosomiasis. The review emphasises work undertaken in the author's laboratory and those of his chief collaborators in the search for a vaccine against schistosomiasis japonica, a disease of major public health significance in The People's Republic of China and The Philippines. Schistosomiasis vaccines should not be considered as the panacea for schistosomiasis control as, when available, it is generally envisaged that they would be used as one component of an integrated strategy complementing currently available and effective tools such as chemotherapy, improvements to sanitation, piped water supply, effective sewage draining and health education.
Collapse
Affiliation(s)
- D P McManus
- Molecular Parasitology Unit, Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research, Australia.
| |
Collapse
|
16
|
Maizels RM, Holland MJ, Falcone FH, Zang XX, Yazdanbakhsh M. Vaccination against helminth parasites--the ultimate challenge for vaccinologists? Immunol Rev 1999; 171:125-47. [PMID: 10582168 DOI: 10.1111/j.1600-065x.1999.tb01345.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Helminths are multicellular pathogens which infect vast numbers of human and animal hosts, causing widespread chronic disease and morbidity. Vaccination against these parasites requires more than identification of effective target antigens, because without understanding the immunology of the host-parasite relationship, ineffective immune mechanisms may be invoked, and there is a danger of amplifying immunopathogenic responses. The fundamental features of the immune response to helminths are therefore summarised in the context of vaccines to helminth parasites. The contention between type-1 and type-2 responses is a central issue in helminth infections, which bias the immune system strongly to the type-2 pathway. Evidence from both human and experimental animal infections indicates that both lineages contribute to immunity in differing circumstances, and that a balanced response leads to the most favourable outcome. A diversity of immune mechanisms can be brought to bear on various helminth species, ranging from antibody-independent macrophages, antibody-dependent granulocyte killing, and nonlymphoid actions, particularly in the gut. This diversity is highlighted by analysis of rodent infections, particularly in comparisons of cytokine-depleted and gene-targeted animals. This knowledge of protective mechanisms needs to be combined with a careful choice of parasite antigens for vaccines. Many existing candidates have been selected with host antibodies, rather than T-cell responses, and include a preponderance of highly conserved proteins with similarities to mammalian or invertebrate antigens. Advantage has yet to be taken of parasite genome projects, or of directed searches for novel, parasite-specific antigens and targets expressed only by infective stages and not mature forms which may generate immunopathology. With advances under way in parasite genomics and new vaccine delivery systems offering more rapid assessment and development, there are now excellent opportunities for new antihelminth vaccines.
Collapse
Affiliation(s)
- R M Maizels
- Institute of Cell, Animal and Population Biology, University of Edinburgh, UK.
| | | | | | | | | |
Collapse
|