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Yokoyama S. HDL Receptor in Schistosoma japonicum Mediating Egg Embryonation: Potential Molecular Basis for High Prevalence of Cholesteryl Ester Transfer Protein Deficiency in East Asia. Front Cell Dev Biol 2022; 10:807289. [PMID: 35372338 PMCID: PMC8968628 DOI: 10.3389/fcell.2022.807289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/21/2022] [Indexed: 12/03/2022] Open
Abstract
Schistosomiasis is a life-threatening parasitic disease caused by blood flukes, Schistosomes. In its intestinal type, the parasites reside in visceral/portal veins of the human hosts and lay eggs to excrete in feces via intestinal tracts, and some of the aberrant eggs plug into the liver via the portal blood flow. Ectopic growth of these eggs causes fatal granulomatosis and cirrhosis of the liver. The parasites ingest nutrients from the host blood plasma by using nonspecific and specific transport via their body surface and alimentary tracts. It is especially important for the female adults to obtain lipid molecules because they synthesize neither fatty acids nor sterols and yet produce egg yolk. Low-density lipoprotein receptors have been identified in the body of the Schistosomes but their functions in the parasite life cycle have not clearly been characterized. On the other hand, CD36-related protein was identified in the body and the eggs of Asian blood fluke, Schistosoma japonicum, and characterized as a molecule that mediates selective uptake of cholesteryl ester from the host plasma high-density lipoproteins (HDLs). This reaction was shown crucial for their eggs to grow to miracidia. Interestingly, abnormal large HDL generated in lack of cholesteryl ester transfer protein (CETP) is a poor substrate for this reaction, and, therefore, CETP deficiency resists pathogenic ectopic growth of the aberrant parasite eggs in the liver. This genetic mutation is exclusively found in East Asia, overlapping with the current and historic regions of Schistosoma japonicum epidemic, so that this infection could be related to high prevalence of CETP deficiency in East Asia.
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Al-Naseri A, Al-Absi S, El Ridi R, Mahana N. A comprehensive and critical overview of schistosomiasis vaccine candidates. J Parasit Dis 2021; 45:557-580. [PMID: 33935395 PMCID: PMC8068781 DOI: 10.1007/s12639-021-01387-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 03/31/2021] [Indexed: 12/11/2022] Open
Abstract
A digenetic platyhelminth Schistosoma is the causative agent of schistosomiasis, one of the neglected tropical diseases that affect humans and animals in numerous countries in the Middle East, sub-Saharan Africa, South America and China. Several control methods were used for prevention of infection or treatment of acute and chronic disease. Mass drug administration led to reduction in heavy-intensity infections and morbidity, but failed to decrease schistosomiasis prevalence and eliminate transmission, indicating the need to develop anti-schistosome vaccine to prevent infection and parasite transmission. This review summarizes the efficacy and protective capacity of available schistosomiasis vaccine candidates with some insights and future prospects.
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Affiliation(s)
- Aya Al-Naseri
- Zoology Department, Faculty of Science, Cairo Univesity, Giza, 12613 Egypt
| | - Samar Al-Absi
- Zoology Department, Faculty of Science, Cairo Univesity, Giza, 12613 Egypt
| | - Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo Univesity, Giza, 12613 Egypt
| | - Noha Mahana
- Zoology Department, Faculty of Science, Cairo Univesity, Giza, 12613 Egypt
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Molehin AJ, Gray SA, Turner C, Davis J, Zhang W, Khatoon S, Rattan M, Kernen R, Peterson C, Sennoune SR, Carter D, Siddiqui AA. Process Development of Sj-p80: A Low-Cost Transmission-Blocking Veterinary Vaccine for Asiatic Schistosomiasis. Front Immunol 2021; 11:578715. [PMID: 33732227 PMCID: PMC7959798 DOI: 10.3389/fimmu.2020.578715] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 12/30/2020] [Indexed: 11/16/2022] Open
Abstract
Asiatic schistosomiasis caused by Schistosoma japonicum is a neglected tropical disease resulting in significant morbidity to both humans and animals - particularly bovines - in endemic areas. Infection with this parasite leads to less healthy herds, causing problems in communities which rely on bovines for farming, milk and meat production. Additionally, excretion of parasite eggs in feces perpetuates the life cycle and can lead to human infection. We endeavored to develop a minimally purified, inexpensive, and effective vaccine based on the 80 kDa large subunit of the calcium activated neutral protease (calpain) from S. japonicum (Sj-p80). Here we describe the production of veterinary vaccine-grade Sj-p80 at four levels of purity and demonstrate in a pilot study that minimally purified antigen provides protection against infection in mice when paired with a low-cost veterinary adjuvant, Montanide™ ISA61 VG. Preliminary data demonstrate that the vaccine is immunogenic with robust antibody titers following immunization, and vaccination resulted in a reduction of parasite eggs being deposited in the liver (23.4-51.4%) and intestines (1.9-55.1%) depending on antigen purity as well as reducing the ability of these eggs to hatch into miracidia by up to 31.6%. We therefore present Sj-p80 as a candidate vaccine antigen for Asiatic schistosomiasis which is now primed for continued development and testing in bovines in endemic areas. A successful bovine vaccine could play a major role in reducing pathogen transmission to humans by interrupting the parasitic life cycle and improving quality of life for people living in endemic countries.
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Affiliation(s)
- Adebayo J. Molehin
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Internal Medicine, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Sean A. Gray
- PAI Life Sciences Inc, Seattle, WA, United States
| | - Cheri Turner
- PAI Life Sciences Inc, Seattle, WA, United States
| | | | - Weidong Zhang
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Internal Medicine, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Sabiha Khatoon
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Internal Medicine, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Madison Rattan
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Rebecca Kernen
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Christopher Peterson
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Souad R. Sennoune
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | | | - Afzal A. Siddiqui
- Center for Tropical Medicine and Infectious Diseases, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Internal Medicine, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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Macháček T, Šmídová B, Pankrác J, Majer M, Bulantová J, Horák P. Nitric oxide debilitates the neuropathogenic schistosome Trichobilharzia regenti in mice, partly by inhibiting its vital peptidases. Parasit Vectors 2020; 13:426. [PMID: 32819437 PMCID: PMC7439556 DOI: 10.1186/s13071-020-04279-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022] Open
Abstract
Background Avian schistosomes, the causative agents of human cercarial dermatitis (or swimmer’s itch), die in mammals but the mechanisms responsible for parasite elimination are unknown. Here we examined the role of reactive nitrogen species, nitric oxide (NO) and peroxynitrite, in the immune response of mice experimentally infected with Trichobilharzia regenti, a model species of avian schistosomes remarkable for its neuropathogenicity. Methods Inducible NO synthase (iNOS) was localized by immunohistochemistry in the skin and the spinal cord of mice infected by T. regenti. The impact of iNOS inhibition by aminoguanidine on parasite burden and growth was then evaluated in vivo. The vulnerability of T. regenti schistosomula to NO and peroxynitrite was assessed in vitro by viability assays and electron microscopy. Additionally, the effect of NO on the activity of T. regenti peptidases was tested using a fluorogenic substrate. Results iNOS was detected around the parasites in the epidermis 8 h post-infection and also in the spinal cord 3 days post-infection (dpi). Inhibition of iNOS resulted in slower parasite growth 3 dpi, but the opposite effect was observed 7 dpi. At the latter time point, moderately increased parasite burden was also noticed in the spinal cord. In vitro, NO did not impair the parasites, but inhibited the activity of T. regenti cathepsins B1.1 and B2, the peptidases essential for parasite migration and digestion. Peroxynitrite severely damaged the surface tegument of the parasites and decreased their viability in vitro, but rather did not participate in parasite clearance in vivo. Conclusions Reactive nitrogen species, specifically NO, do not directly kill T. regenti in mice. NO promotes the parasite growth soon after penetration (3 dpi), but prevents it later (7 dpi) when also suspends the parasite migration in the CNS. NO-related disruption of the parasite proteolytic machinery is partly responsible for this effect. ![]()
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Affiliation(s)
- Tomáš Macháček
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia.
| | - Barbora Šmídová
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Jan Pankrác
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia.,Center for Advanced Preclinical Imaging, First Faculty of Medicine, Charles University, Prague, Czechia
| | - Martin Majer
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Jana Bulantová
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Petr Horák
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
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Stutzer C, Richards SA, Ferreira M, Baron S, Maritz-Olivier C. Metazoan Parasite Vaccines: Present Status and Future Prospects. Front Cell Infect Microbiol 2018; 8:67. [PMID: 29594064 PMCID: PMC5859119 DOI: 10.3389/fcimb.2018.00067] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 02/26/2018] [Indexed: 12/21/2022] Open
Abstract
Eukaryotic parasites and pathogens continue to cause some of the most detrimental and difficult to treat diseases (or disease states) in both humans and animals, while also continuously expanding into non-endemic countries. Combined with the ever growing number of reports on drug-resistance and the lack of effective treatment programs for many metazoan diseases, the impact that these organisms will have on quality of life remain a global challenge. Vaccination as an effective prophylactic treatment has been demonstrated for well over 200 years for bacterial and viral diseases. From the earliest variolation procedures to the cutting edge technologies employed today, many protective preparations have been successfully developed for use in both medical and veterinary applications. In spite of the successes of these applications in the discovery of subunit vaccines against prokaryotic pathogens, not many targets have been successfully developed into vaccines directed against metazoan parasites. With the current increase in -omics technologies and metadata for eukaryotic parasites, target discovery for vaccine development can be expedited. However, a good understanding of the host/vector/pathogen interface is needed to understand the underlying biological, biochemical and immunological components that will confer a protective response in the host animal. Therefore, systems biology is rapidly coming of age in the pursuit of effective parasite vaccines. Despite the difficulties, a number of approaches have been developed and applied to parasitic helminths and arthropods. This review will focus on key aspects of vaccine development that require attention in the battle against these metazoan parasites, as well as successes in the field of vaccine development for helminthiases and ectoparasites. Lastly, we propose future direction of applying successes in pursuit of next generation vaccines.
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Affiliation(s)
- Christian Stutzer
- Tick Vaccine Group, Department of Genetics, University of Pretoria, Pretoria, South Africa
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Wang Q, Da'dara AA, Skelly PJ. The human blood parasite Schistosoma mansoni expresses extracellular tegumental calpains that cleave the blood clotting protein fibronectin. Sci Rep 2017; 7:12912. [PMID: 29018227 PMCID: PMC5635006 DOI: 10.1038/s41598-017-13141-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 09/19/2017] [Indexed: 11/09/2022] Open
Abstract
Schistosomes are intravascular, parasitic flatworms that cause debilitating disease afflicting >200 million people. Proteins expressed at the host-parasite interface likely play key roles in modifying the worm's local environment to ensure parasite survival. Proteomic analysis reveals that two proteases belonging to the calpain family (SmCalp1 and SmCalp2) are expressed in the Schistosoma mansoni tegument. We have cloned both; while highly conserved in domain organization they display just 31% amino acid sequence identity. Both display high relative expression in the parasite's intravascular life forms. Immunolocalization and activity based protein profiling experiments confirm the presence of the enzymes at the host-parasite interface. Living parasites exhibit surface calpain activity that is blocked in the absence of calcium and in the presence of calpain inhibitors (E64c, PD 150606 and calpastatin). While calpains are invariably reported to be exclusively intracellular (except in diseased or injured tissues), our data show that schistosomes display unique, constitutive, functional extracellular calpain activity. Furthermore we show that the worms are capable of cleaving the host blood clotting protein fibronectin and that this activity can be inhibited by E64c. We hypothesize that SmCalp1 and/or SmCalp2 perform this cleavage function to impede blood clot formation around the worms in vivo.
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Affiliation(s)
- Qiang Wang
- Molecular Helminthology Laboratory, Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, 01536, USA
| | - Akram A Da'dara
- Molecular Helminthology Laboratory, Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, 01536, USA
| | - Patrick J Skelly
- Molecular Helminthology Laboratory, Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine, Tufts University, North Grafton, MA, 01536, USA.
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Nitric oxide blocks the development of the human parasite Schistosoma japonicum. Proc Natl Acad Sci U S A 2017; 114:10214-10219. [PMID: 28874579 DOI: 10.1073/pnas.1708578114] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human schistosomiasis, caused by Schistosoma species, is a major public health problem affecting more than 700 million people in 78 countries, with over 40 mammalian host reservoir species complicating the transmission ecosystem. The primary cause of morbidity is considered to be granulomas induced by fertilized eggs of schistosomes in the liver and intestines. Some host species, like rats (Rattus norvegicus), are naturally intolerant to Schistosoma japonicum infection, and do not produce granulomas or pose a threat to transmission, while others, like mice and hamsters, are highly susceptible. The reasons behind these differences are still a mystery. Using inducible nitric oxide synthase knockout (iNOS-/-) Sprague-Dawley rats, we found that inherent high expression levels of iNOS in wild-type (WT) rats play an important role in blocking growth, reproductive organ formation, and egg development in S. japonicum, resulting in production of nonfertilized eggs. Granuloma formation, induced by fertilized eggs in the liver, was considerably exacerbated in the iNOS-/- rats compared with the WT rats. This inhibition by nitric oxide acts by affecting mitochondrial respiration and energy production in the parasite. Our work not only elucidates the innate mechanism that blocks the development and production of fertilized eggs in S. japonicum but also offers insights into a better understanding of host-parasite interactions and drug development strategies against schistosomiasis.
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Salmonella typhimurium Infection Reduces Schistosoma japonicum Worm Burden in Mice. Sci Rep 2017; 7:1349. [PMID: 28465515 PMCID: PMC5430953 DOI: 10.1038/s41598-017-00992-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/17/2017] [Indexed: 11/09/2022] Open
Abstract
Coinfection of microorganisms is a common phenomenon in humans and animals. In order to further our understanding of the progress of coinfection and the possible interaction between different pathogens, we have built a coinfection mouse model with Schistosoma japonicum and Salmonella typhimurium, and used this model to investigate the systemic metabolic and immune responses using NMR-based metabonomics and immunological techniques. Our results show that Salmonella typhimurium (ATCC14028) infection reduces the number of adult schistosomal worms and eggs, relieves symptoms of schistosomiasis and also abates the mortality of mice infected by Schistosoma japonicum. In addition, Salmonella typhimurium infection counteracts the metabolic disturbances associated with schistosomiasis, which was reflected by the reverted levels of metabolites in coinfected mice, compared with the Schistosoma japonicum infected mice. Furthermore, immune analyses also indicate that shift of the immune response to different pathogens is a result of indirect interactions between Schistosoma japonicum and Salmonella typhimurium within the host. Salmonella typhimurium infection can ameliorate Schistosoma japonicum-caused schistosomiasis in BALB/c mice, which is most likely due to inverse immune polarization. Our work provides an insight into coinfection between Schistosoma japonicum and Salmonella typhimurium, and may further contribute to the development of new tools for controlling Schistosoma japonicum-associated diseases.
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Molehin AJ, Rojo JU, Siddiqui SZ, Gray SA, Carter D, Siddiqui AA. Development of a schistosomiasis vaccine. Expert Rev Vaccines 2016; 15:619-27. [PMID: 26651503 PMCID: PMC5070536 DOI: 10.1586/14760584.2016.1131127] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Schistosomiasis is a neglected tropical disease (NTD) of public health importance. Despite decades of implementation of mass praziquantel therapy programs and other control measures, schistosomiasis has not been contained and continues to spread to new geographic areas. A schistosomiasis vaccine could play an important role as part of a multifaceted control approach. With regards to vaccine development, many biological bottlenecks still exist: the lack of reliable surrogates of protection in humans; immune interactions in co-infections with other diseases in endemic areas; the potential risk of IgE responses to antigens in endemic populations; and paucity of appropriate vaccine efficacy studies in nonhuman primate models. Research is also needed on the role of modern adjuvants targeting specific parts of the innate immune system to tailor a potent and protective immune response for lead schistosome vaccine candidates with the long-term aim to achieve curative worm reduction. This review summarizes the current status of schistosomiasis vaccine development.
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Affiliation(s)
- Adebayo J. Molehin
- Department of Internal Medicine, Texas Tech University School of Medicine, Lubbock, Texas, USA
- Center of Tropical Medicine and Infectious Diseases, Texas Tech University School of Medicine, Lubbock, Texas, USA
| | - Juan U. Rojo
- Department of Internal Medicine, Texas Tech University School of Medicine, Lubbock, Texas, USA
- Center of Tropical Medicine and Infectious Diseases, Texas Tech University School of Medicine, Lubbock, Texas, USA
| | - Sabrina Z. Siddiqui
- Department of Internal Medicine, Texas Tech University School of Medicine, Lubbock, Texas, USA
- Center of Tropical Medicine and Infectious Diseases, Texas Tech University School of Medicine, Lubbock, Texas, USA
| | | | - Darrick Carter
- PAI Life Sciences, Washington, USA
- Infectious Disease Research Institute, Seattle, Washington, USA
| | - Afzal A. Siddiqui
- Department of Internal Medicine, Texas Tech University School of Medicine, Lubbock, Texas, USA
- Center of Tropical Medicine and Infectious Diseases, Texas Tech University School of Medicine, Lubbock, Texas, USA
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van Panhuys N. TCR Signal Strength Alters T-DC Activation and Interaction Times and Directs the Outcome of Differentiation. Front Immunol 2016; 7:6. [PMID: 26834747 PMCID: PMC4725058 DOI: 10.3389/fimmu.2016.00006] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 01/08/2016] [Indexed: 12/13/2022] Open
Abstract
The ability of CD4+ T cells to differentiate into effector subsets underpins their ability to shape the immune response and mediate host protection. During T cell receptor-induced activation of CD4+ T cells, both the quality and quantity of specific activatory peptide/MHC ligands have been shown to control the polarization of naive CD4+ T cells in addition to co-stimulatory and cytokine-based signals. Recently, advances in two--photon microscopy and tetramer-based cell tracking methods have allowed investigators to greatly extend the study of the role of TCR signaling in effector differentiation under in vivo conditions. In this review, we consider data from recent in vivo studies analyzing the role of TCR signal strength in controlling the outcome of CD4+ T cell differentiation and discuss the role of TCR in controlling the critical nature of CD4+ T cell interactions with dendritic cells during activation. We further propose a model whereby TCR signal strength controls the temporal aspects of T-DC interactions and the implications for this in mediating the downstream signaling events, which influence the transcriptional and epigenetic regulation of effector differentiation.
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Affiliation(s)
- Nicholas van Panhuys
- Division of Experimental Biology, Sidra Medical and Research Center , Doha , Qatar
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Yokoyama S, Okumura-Noji K, Lu R. Prevention of fatal hepatic complication in schistosomiasis by inhibition of CETP. J Biomed Res 2015; 29:176-88. [PMID: 26060442 PMCID: PMC4449486 DOI: 10.7555/jbr.29.20150005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 01/26/2015] [Indexed: 11/04/2022] Open
Abstract
Schistosoma japonicum, once endemic all the East Asia, remains as a serious public health problem in certain regions. Ectopic egg embryonation in the liver causes granulomatosis and eventually fatal cirrhosis, so that prevention of this process is one of the keys to reduce its mortality. The embryonation requires cholesteryl ester from HDL of the host blood for egg yolk formation, and this reaction is impaired from the abnormal large HDL in genetic cholesteryl ester transfer protein (CETP) deficiency. When CETP was expressed in mice that otherwise lack this protein, granulomatosis of the liver was shown increased compared to the wild type upon infection of Schistosoma japonicum. The CETP deficiencies accumulated exclusively in East Asia, from Indochina to Siberia, so that Shistosomiasis can be a screening factor for this accumulation. CD36 related protein (CD36RP) was identified as a protein for this reaction, cloned from the cDNA library of Schistosoma japonicum with 1880-bp encoding 506 amino acids. The antibody against the extracellular loop of CD36RP inhibited cholesteryl ester uptake from HDL and suppressed egg embryonation in culture. Therefore, inhibition of CETP is a potential approach to prevent liver granulomatosis and thereby fatal liver cirrhosis in the infection of Schistosoma japonicum.
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Affiliation(s)
- Shinji Yokoyama
- Nutritional Health Science Research Center, Chubu University, Kasugai 487-8501, Japan.
| | - Kuniko Okumura-Noji
- Nutritional Health Science Research Center, Chubu University, Kasugai 487-8501, Japan.
| | - Rui Lu
- Nutritional Health Science Research Center, Chubu University, Kasugai 487-8501, Japan.
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Ran L, Yu Q, Zhang S, Xiong F, Cheng J, Yang P, Xu JF, Nie H, Zhong Q, Yang X, Yang F, Gong Q, Kuczma M, Kraj P, Gu W, Ren BX, Wang CY. Cx3cr1 deficiency in mice attenuates hepatic granuloma formation during acute schistosomiasis by enhancing the M2-type polarization of macrophages. Dis Model Mech 2015; 8:691-700. [PMID: 26035381 PMCID: PMC4486856 DOI: 10.1242/dmm.018242] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 04/15/2015] [Indexed: 12/29/2022] Open
Abstract
Acute schistosomiasis is characterized by pro-inflammatory responses against tissue- or organ-trapped parasite eggs along with granuloma formation. Here, we describe studies in Cx3cr1−/− mice and demonstrate the role of Cx3cr1 in the pathoetiology of granuloma formation during acute schistosomiasis. Mice deficient in Cx3cr1 were protected from granuloma formation and hepatic injury induced by Schistosoma japonicum eggs, as manifested by reduced body weight loss and attenuated hepatomegaly along with preserved liver function. Notably, S. japonicum infection induced high levels of hepatic Cx3cr1 expression, which was predominantly expressed by infiltrating macrophages. Loss of Cx3cr1 rendered macrophages preferentially towards M2 polarization, which then led to a characteristic switch of the host immune defense from a conventional Th1 to a typical Th2 response during acute schistosomiasis. This immune switch caused by Cx3cr1 deficiency was probably associated with enhanced STAT6/PPAR-γ signaling and increased expression of indoleamine 2,3-dioxygenase (IDO), an enzyme that promotes M2 polarization of macrophages. Taken together, our data provide evidence suggesting that CX3CR1 could be a viable therapeutic target for treatment of acute schistosomiasis. Highlighted Article: A reduction in CX3CR1 signaling provides protection for mice against pro-inflammatory responses and hepatic granuloma formation during acute schistosomiasis.
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Affiliation(s)
- Lin Ran
- Department of Molecular Biology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Qilin Yu
- The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Shu Zhang
- The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Fei Xiong
- The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Jia Cheng
- The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Ping Yang
- The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China
| | - Jun-Fa Xu
- Department of Clinical Immunology, Institute of Laboratory Medicine, Guangdong Medical College, No. 1 Xincheng Road, Dongguan 523808, China
| | - Hao Nie
- Clinical and Molecular Immunology Research Center, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Qin Zhong
- Department of Molecular Biology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Xueli Yang
- Department of Molecular Biology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Fei Yang
- Clinical and Molecular Immunology Research Center, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Quan Gong
- Department of Immunology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Michal Kuczma
- The Center for Biotechnology and Genomic Medicine, Georgia Regents University, 1120 15th Street, Augusta, GA 30912, USA
| | - Piotr Kraj
- The Center for Biotechnology and Genomic Medicine, Georgia Regents University, 1120 15th Street, Augusta, GA 30912, USA
| | - Weikuan Gu
- Department of Orthopedic Surgery and BME, Campbell-Clinic, University of Tennessee, Health Science Center, Memphis, TN 38163, USA
| | - Bo-Xu Ren
- Department of Molecular Biology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China
| | - Cong-Yi Wang
- Department of Molecular Biology, Medical College of Yangtze University, 1 Nanhuan Road, Jingzhou, Hubei 434023, China The Center for Biomedical Research, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Avenue, Wuhan 430030, China Department of Clinical Immunology, Institute of Laboratory Medicine, Guangdong Medical College, No. 1 Xincheng Road, Dongguan 523808, China
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Fonseca CT, Oliveira SC, Alves CC. Eliminating Schistosomes through Vaccination: What are the Best Immune Weapons? Front Immunol 2015; 6:95. [PMID: 25806033 PMCID: PMC4353369 DOI: 10.3389/fimmu.2015.00095] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 02/18/2015] [Indexed: 12/24/2022] Open
Abstract
The successful development of vaccines depends on the knowledge of the immunological mechanisms associated with the elimination of the pathogen. In the case of schistosomes, its complex life cycle and the mechanisms developed to evade host immune system, turns the development of a vaccine against the disease into a very difficult task. Identifying the immunological effector mechanisms involved in parasite attrition and the major targets for its response is a key step to formulate an effective vaccine. Recent studies have described some promising antigens to compose a subunit vaccine and have pointed to some immune factors that play a role in parasite elimination. Here, we review the immune components and effector mechanisms associated with the protective immunity induced by those vaccine candidates and the lessons we have learned from the studies of the acquired resistance to infection in humans. We will also discuss the immune factors that correlate with protection and therefore could help to evaluate those vaccine formulations in clinical trials.
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Affiliation(s)
- Cristina Toscano Fonseca
- Laboratório de Esquistossomose do Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Sergio Costa Oliveira
- Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Departamento de Bioquímica e Imunologia do Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Clarice Carvalho Alves
- Laboratório de Esquistossomose do Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz , Belo Horizonte , Brazil
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14
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Mbanefo EC, Kumagai T, Kodama Y, Kurosaki T, Furushima-Shimogawara R, Cherif MS, Mizukami S, Kikuchi M, Huy NT, Ohta N, Sasaki H, Hirayama K. Immunogenicity and anti-fecundity effect of nanoparticle coated glutathione S-transferase (SjGST) DNA vaccine against murine Schistosoma japonicum infection. Parasitol Int 2015; 64:24-31. [PMID: 25603531 DOI: 10.1016/j.parint.2015.01.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 12/10/2014] [Accepted: 01/11/2015] [Indexed: 01/10/2023]
Abstract
There is still urgent need for a vaccine against schistosomiasis, especially in Schistosoma japonicum endemic areas where even a vaccine that will interrupt zoonotic transmission will be potentially effective as an intervention tool. We had developed a novel nanoparticle gene delivery system, which has proven efficacious in gene transfection to target immune cells with complementary adjuvant effect and high protective efficacy in several diseases. Here, we applied this nanoparticle system in combination with S. japonicum glutathione S-transferase (SjGST) DNA vaccine to show the immunogenicity and anti-fecundity effect of the nanoparticle coated vaccine formulation against murine schistosomiasis. The nanoparticle-coated DNA vaccine formulation induced desired immune responses. In comparison with the nanoparticle coated empty vector, it produced significantly increased antigen-specific humoral response, T-helper 1 polarized cytokine environment, higher proportion of IFN-γ producing CD4(+) T-cells and the concomitant decrease in IL-4 producing CD4(+) T-cells. Although there was no effect on worm burden, we recorded a marked reduction in tissue egg burden. There was up to 71.3% decrease in tissue egg burden and 55% reduction in the fecundity of female adult worms. Our data showed that SjGST DNA vaccine, delivered using the nanoparticle gene delivery system, produced anti-fecundity effect on female adult schistosomes as previously described by using conventional subunit vaccine with adjuvant, proving this DNA vaccine formulation as a promising candidate for anti-pathology and transmission blocking application.
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Affiliation(s)
- Evaristus Chibunna Mbanefo
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN) and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Department of Parasitology and Entomology, Faculty of Bioscience, Nnamdi Azikiwe University, P.M.B. 5025, Awka, Nigeria
| | - Takashi Kumagai
- Section of Environmental Parasitology, Tokyo Medical and Dental University Graduate School of Medical and Dental Science, 113-8519, Japan
| | - Yukinobu Kodama
- Department of Hospital Pharmacy, Nagasaki University Hospital, 1-7-1 Sakamoto, 852-8501, Japan
| | - Tomoaki Kurosaki
- Department of Hospital Pharmacy, Nagasaki University Hospital, 1-7-1 Sakamoto, 852-8501, Japan
| | - Rieko Furushima-Shimogawara
- Section of Environmental Parasitology, Tokyo Medical and Dental University Graduate School of Medical and Dental Science, 113-8519, Japan
| | - Mahamoud Sama Cherif
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN) and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan
| | - Shusaku Mizukami
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN) and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan
| | - Mihoko Kikuchi
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN) and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan
| | - Nguyen Tien Huy
- Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Department of Clinical Product Development, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan
| | - Nobuo Ohta
- Section of Environmental Parasitology, Tokyo Medical and Dental University Graduate School of Medical and Dental Science, 113-8519, Japan
| | - Hitoshi Sasaki
- Department of Hospital Pharmacy, Nagasaki University Hospital, 1-7-1 Sakamoto, 852-8501, Japan
| | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN) and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan; Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, 852-8523, Japan.
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15
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Abstract
Schistosomiasis is one of the most prevalent, insidious and serious of the tropical parasitic diseases. Although the effective anthelmintic drug, praziquantel, is widely available and cheap, it does not protect against re-infection, drug-resistant schistosome may evolve and mass drug administration programmes based around praziquantel are probably unsustainable long term. Whereas protective anti-schistosome vaccines are not yet available, the zoonotic nature of Schistosoma japonicum provides a novel approach for developing a transmission-blocking veterinary vaccine in domestic animals, especially bovines, which are major reservoir hosts, being responsible for up to 90% of environmental egg contamination in China and the Philippines. However, a greater knowledge of schistosome immunology is required to understand the processes associated with anti-schistosome protective immunity and to reinforce the rationale for vaccine development against schistosomiasis japonica. Importantly as well, improved diagnostic tests, with high specificity and sensitivity, which are simple, rapid and able to diagnose light S. japonicum infections, are required to determine the extent of transmission interruption and the complete elimination of schistosomiasis following control efforts. This article discusses aspects of the host immune response in schistosomiasis, the current status of vaccine development against S. japonicum and reviews approaches for diagnosing and detecting schistosome infections in mammalian hosts.
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16
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Mbanefo EC, Huy NT, Wadagni AA, Eneanya CI, Nwaorgu O, Hirayama K. Host determinants of reinfection with schistosomes in humans: a systematic review and meta-analysis. PLoS Negl Trop Dis 2014; 8:e3164. [PMID: 25211227 PMCID: PMC4161334 DOI: 10.1371/journal.pntd.0003164] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 08/04/2014] [Indexed: 12/12/2022] Open
Abstract
Background Schistosomiasis is still a major public health burden in the tropics and subtropics. Although there is an effective chemotherapy (Praziquantel) for this disease, reinfection occurs rapidly after mass drug administration (MDA). Because the entire population do not get reinfected at the same rate, it is possible that host factors may play a dominant role in determining resistance or susceptibility to reinfection with schistosomes. Here, we systematically reviewed and meta-analyzed studies that reported associations between reinfection with the principal human-infecting species (S. mansoni, S. japonicum and S. haematobium) and host socio-demographic, epidemiological, immunological and genetic factors. Methodology/Principal Findings PubMed, Scopus, Google Scholar, Cochrane Review Library and African Journals Online public databases were searched in October 2013 to retrieve studies assessing association of host factors with reinfection with schistosomes. Meta-analysis was performed to generate pooled odds ratios and standardized mean differences as overall effect estimates for dichotomous and continuous variables, respectively. Quality assessment of included studies, heterogeneity between studies and publication bias were also assessed. Out of the initial 2739 records, 109 studies were included in the analyses, of which only 32 studies with 37 data sets were eligible for quantitative data synthesis. Among several host factors identified, strong positive association was found with age and pre-treatment intensity, and only slightly for gender. These factors are major determinants of exposure and disease transmission. Significant positive association was found with anti-SWA IgG4 level, and a negative overall effect for association with IgE levels. This reconfirmed the concept that IgE/IgG4 balance is a major determinant of protective immunity against schistosomiasis. Other identified determinants were reported by a small number of studies to enable interpretation. Conclusions Our data contribute to the understanding of host-parasite interaction as it affects reinfection, and is a potential tool to guide planning and tailoring of community interventions to target high-risk groups. One of the major challenges of schistosomiasis control is that disease prevalence reverts to baseline levels after mass drug administration due to high rate of reinfection. Host factors play a major role in determining resistance or susceptibility to reinfection with schistosomiasis and other diseases. We systematically searched and analyzed studies that identified potential host determinants of reinfection with schistosomes. Among demographic variables, age but not gender was strongly associated with reinfection with schistosomes. Pretreatment infection intensity was also identified as a major determinant of reinfection. Positive association with IgG4 levels and negative association with IgE levels reconfirmed the notion that IgE/IgG4 balance is the major factor controlling protective immunity against schistosomiasis. Other factors were reported by few studies to allow correct inferences. These results contribute to our understanding of host-parasite relationship as it affects reinfection, and will be useful for planning and targeting the limited resources for intervention on high-risk groups.
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Affiliation(s)
- Evaristus Chibunna Mbanefo
- Department of Parasitology and Entomology, Faculty of Bioscience, Nnamdi Azikiwe University, Awka, Nigeria
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
- * E-mail: ,
| | - Nguyen Tien Huy
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
| | - Anita Akpeedje Wadagni
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
| | - Christine Ifeoma Eneanya
- Department of Parasitology and Entomology, Faculty of Bioscience, Nnamdi Azikiwe University, Awka, Nigeria
| | - Obioma Nwaorgu
- Department of Parasitology and Entomology, Faculty of Bioscience, Nnamdi Azikiwe University, Awka, Nigeria
| | - Kenji Hirayama
- Department of Immunogenetics, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
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Cruz LJ, Rueda F, Simón L, Cordobilla B, Albericio F, Domingo JC. Liposomes containing NY-ESO-1/tetanus toxoid and adjuvant peptides targeted to human dendritic cells via the Fc receptor for cancer vaccines. Nanomedicine (Lond) 2014; 9:435-49. [DOI: 10.2217/nnm.13.66] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Aim: To improve the immunological response against tumors, a vaccine based on nanoliposomes targeted to the Fcγ-receptor was developed to enhance the immunogenicity of tumor-associated antigens (TAAs). Materials & methods: Using human dendritic cells in vitro, a fragment of the TAA NY-ESO-1 combined with a T-helper peptide from the tetanus toxoid encapsulated in nanoliposomes was evaluated. In addition, peptides Palm-IL-1 and MAP-IFN-γwere coadministered as adjuvants to enhance the immunological response. Results: Coadministration of Palm-IL-1 or MAP-IFN-γpeptide adjuvants and the hybrid NY-ESO-1-tetanus toxoid (soluble or encapsulated in nanoliposomes without targeting) increased immunogenicity. However, the most potent immunological response was obtained when the peptide adjuvants were encapsulated in liposomes targeted to human dendritic cells via the Fc receptor. Conclusion: This targeted vaccine strategy is a promising tool to activate and deliver antigens to dendritic cells, thus improving immunotherapeutic response in situations in which the immune system is frequently compromised, as in advanced cancers.
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Affiliation(s)
- Luis J Cruz
- CIBER-BBN, Networking Centre on Bioengineering, Biomaterials & Nanomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
- Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Felix Rueda
- Department of Biochemistry & Molecular Biology, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain
| | - Lorena Simón
- CIBER-BBN, Networking Centre on Bioengineering, Biomaterials & Nanomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
- Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Begoña Cordobilla
- Department of Biochemistry & Molecular Biology, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain
| | - Fernando Albericio
- CIBER-BBN, Networking Centre on Bioengineering, Biomaterials & Nanomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
- Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona, Spain
- Department of Organic Chemistry, University of Barcelona, Marti i Franques 1, 08028-Barcelona, Spain
- School of Chemistry, University of KwaZulu Natal, Durban, Kwa-Zulu Natal, 4000, South Africa
| | - Joan C Domingo
- Department of Biochemistry & Molecular Biology, University of Barcelona, Diagonal 643, 08028 Barcelona, Spain
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18
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Mushtaq K, Chodisetti SB, Rai PK, Maurya SK, Amir M, Sheikh JA, Agrewala JN. Decision-making critical amino acids: role in designing peptide vaccines for eliciting Th1 and Th2 immune response. Amino Acids 2014; 46:1265-74. [DOI: 10.1007/s00726-014-1692-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 01/31/2014] [Indexed: 11/28/2022]
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19
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Karmakar S, Zhang W, Ahmad G, Torben W, Alam MU, Le L, Damian RT, Wolf RF, White GL, Carey DW, Carter D, Reed SG, Siddiqui AA. Use of an Sm-p80-based therapeutic vaccine to kill established adult schistosome parasites in chronically infected baboons. J Infect Dis 2014; 209:1929-40. [PMID: 24436452 DOI: 10.1093/infdis/jiu031] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
No vaccines are available for human use for any parasitic infections, including the helminthic disease schistosomiasis. Sm-p80, the large subunit of Schistosoma mansoni calpain, is a leading antigen candidate for a schistosomiasis vaccine. Prophylactic and antifecundity efficacies of Sm-p80 have been tested using a variety of vaccine approaches in both rodent and nonhuman primate models. However, the therapeutic efficacy of a Sm-p80-based vaccine had not been determined. In this study, we evaluated the therapeutic efficacy of Sm-p80 by using 2 different strategies and 3 Sm-p80-based vaccine formulations in baboons. Vaccine formulations were able to decrease established adult worms by 10%-36%, reduce retention of eggs in tissues by 10%-57%, and decrease egg excretion in feces by 13%-33%, compared with control formulations. Marked differences were observed in B and T cell immune correlates between vaccinated and control animals. This is the first report of killing of established adult schistosome worms by a vaccine. In addition to distinct prophylactic efficacy of Sm-p80, this study adds to the evidence that Sm-p80 is a potentially important antigen with both substantial prophylactic and therapeutic efficacies. These data reinforce that Sm-p80 should be moved forward along the path toward human clinical trials.
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Affiliation(s)
- Souvik Karmakar
- Center for Tropical Medicine and Infectious Diseases Department of Immunology and Molecular Microbiology
| | - Weidong Zhang
- Center for Tropical Medicine and Infectious Diseases Department of Immunology and Molecular Microbiology
| | - Gul Ahmad
- Department of Natural Sciences, School of Arts and Sciences, Peru State College, Nebraska
| | - Workineh Torben
- Tulane National Primate Research Center, Covington, Louisiana
| | - Mayeen U Alam
- Center for Tropical Medicine and Infectious Diseases Department of Immunology and Molecular Microbiology
| | - Loc Le
- Center for Tropical Medicine and Infectious Diseases Department of Immunology and Molecular Microbiology
| | | | - Roman F Wolf
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City
| | - Gary L White
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City
| | - David W Carey
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City
| | - Darrick Carter
- Infectious Disease Research Institute PAI Life Sciences, Seattle, Washington
| | | | - Afzal A Siddiqui
- Center for Tropical Medicine and Infectious Diseases Department of Immunology and Molecular Microbiology Department of Internal Medicine Department of Pathology, Texas Tech University Health Sciences Center, Lubbock
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20
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Jia X, Schulte L, Loukas A, Pickering D, Pearson M, Mobli M, Jones A, Rosengren KJ, Daly NL, Gobert GN, Jones MK, Craik DJ, Mulvenna J. Solution structure, membrane interactions, and protein binding partners of the tetraspanin Sm-TSP-2, a vaccine antigen from the human blood fluke Schistosoma mansoni. J Biol Chem 2014; 289:7151-7163. [PMID: 24429291 DOI: 10.1074/jbc.m113.531558] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The tetraspanins (TSPs) are a family of integral membrane proteins that are ubiquitously expressed at the surface of eukaryotic cells. TSPs mediate a range of processes at the surface of the plasma membrane by providing a scaffold for the assembly of protein complexes known as tetraspanin-enriched microdomains (TEMs). We report here the structure of the surface-exposed EC2 domain from Sm-TSP-2, a TSP from Schistosoma mansoni and one of the better prospects for the development of a vaccine against schistosomiasis. This is the first solution structure of this domain, and our investigations of its interactions with lipid micelles provide a general model for interactions between TSPs, membranes, and other proteins. Using chemical cross-linking, eight potential protein constituents of Sm-TSP-2-mediated TEMs were also identified. These include proteins important for membrane maintenance and repair, providing further evidence for the functional role of Sm-TSP-2- and Sm-TSP-2-mediated TEMs. The identification of calpain, Sm29, and fructose-bisphosphate aldolase, themselves potential vaccine antigens, suggests that the Sm-TSP-2-mediated TEMs could be disrupted via multiple targets. The identification of further Sm-TSP-2-mediated TEM proteins increases the available candidates for multiplex vaccines and/or novel drugs targeting TEMs in the schistosome tegument.
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Affiliation(s)
- Xinying Jia
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | - Leigh Schulte
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia; The University of Queensland, School of Veterinary Sciences, Gatton, QLD 4343, Australia
| | - Alex Loukas
- Centre for Biodiscovery and Molecular Development of Therapeutics, Queensland Tropical Health Alliance, James Cook University, Cairns, QLD 4878, Australia
| | - Darren Pickering
- Centre for Biodiscovery and Molecular Development of Therapeutics, Queensland Tropical Health Alliance, James Cook University, Cairns, QLD 4878, Australia
| | - Mark Pearson
- Centre for Biodiscovery and Molecular Development of Therapeutics, Queensland Tropical Health Alliance, James Cook University, Cairns, QLD 4878, Australia
| | - Mehdi Mobli
- The University of Queensland, Centre for Advanced Imaging, Brisbane, QLD 4072, Australia
| | - Alun Jones
- The University of Queensland, Institute for Molecular Bioscience, Brisbane, QLD 4072, Australia
| | - Karl J Rosengren
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia
| | - Norelle L Daly
- Centre for Biodiscovery and Molecular Development of Therapeutics, Queensland Tropical Health Alliance, James Cook University, Cairns, QLD 4878, Australia
| | - Geoffrey N Gobert
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia
| | - Malcolm K Jones
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia; The University of Queensland, School of Veterinary Sciences, Gatton, QLD 4343, Australia
| | - David J Craik
- The University of Queensland, Institute for Molecular Bioscience, Brisbane, QLD 4072, Australia
| | - Jason Mulvenna
- Queensland Institute of Medical Research, Brisbane, QLD 4006, Australia; The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia.
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21
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Karmakar S, Zhang W, Ahmad G, Torben W, Alam MU, Le L, Damian RT, Wolf RF, White GL, Carey DW, Carter D, Reed SG, Siddiqui AA. Cross-species protection: Schistosoma mansoni Sm-p80 vaccine confers protection against Schistosoma haematobium in hamsters and baboons. Vaccine 2014; 32:1296-303. [PMID: 24397898 DOI: 10.1016/j.vaccine.2013.12.057] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/09/2013] [Accepted: 12/18/2013] [Indexed: 01/02/2023]
Abstract
The ability of the Schistosoma mansoni antigen, Sm-p80, to provide cross-species protection against Schistosoma haematobium challenge was evaluated in hamster and baboon models. Pronounced reduction in worm burden (48%) and in tissue egg load (64%) was observed in hamsters vaccinated with recombinant Sm-p80 admixed with glucopyranosyl lipid adjuvant-stable emulsion (GLA-SE). Similarly, in baboons, the Sm-p80/GLA-SE vaccine produced a 25% reduction in S. haematobium adult worms and decreased the egg load in the urinary bladder by 64%. A 40% and 53% reduction in fecal and urine egg output, respectively, was observed in vaccinated baboons. A balanced pro-inflammatory (Th17 and Th1) and Th2 type of response was generated after vaccination and appears indicative of augmented prophylactic efficacy. These data on cross-species protection coupled with the prophylactic, therapeutic and antifecundity efficacy against the homologous parasite, S. mansoni, reinforces Sm-p80 as a promising vaccine candidate. It is currently being prepared for GMP-compliant manufacture and for further pre-clinical development leading to human clinical trials. These results solidify the expectation that the Sm-p80 vaccine will provide relief for both the intestinal and the urinary schistosomiasis and thus will be greatly beneficial in reducing the overall burden of schistosomiasis.
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Affiliation(s)
- Souvik Karmakar
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Weidong Zhang
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Gul Ahmad
- Department of Natural Sciences, School of Arts & Sciences, Peru State College, Peru, NE 68321, USA
| | - Workineh Torben
- Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Mayeen U Alam
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Loc Le
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
| | - Raymond T Damian
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Roman F Wolf
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Gary L White
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - David W Carey
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Darrick Carter
- Infectious Disease Research Institute, Seattle, WA 98102, USA; PAI Life Sciences, Seattle, WA 98102, USA
| | - Steven G Reed
- Infectious Disease Research Institute, Seattle, WA 98102, USA
| | - Afzal A Siddiqui
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Immunology and Molecular Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA; Department of Pathology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.
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22
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Karmakar S, Zhang W, Ahmad G, Alam MU, Winn R, Torben W, Le L, Tillery KA, Siddiqui AA. Complement plays a minimal role in Sm-p80-mediated protection against Schistosoma mansoni. Hum Vaccin Immunother 2013; 10:640-7. [PMID: 24374377 DOI: 10.4161/hv.27576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Sm-p80, the large subunit of Schistosoma masoni calpain, is a leading antigen candidate for a schistosome vaccine. Prophylactic and antifecundity efficacy of Sm-p80 has been tested using a variety of vaccine approaches. However, the mechanism of Sm-p80-mediated killing is still unknown. In this study, potential role of complement in Sm-p80-mediated protection was studied using both in vitro (cobra venom factor inhibition) and in vivo using mice deficient in C3 (C3 -/-; B6.129S4-C3tm1Crr/J). In the absence of C3, Sm-p80-based vaccine was able to provide significant reduction in adult worm burden following challenge with schistosome cercariae in mice suggesting the effector functions of complement may be limited in this vaccine-induced protection.
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Affiliation(s)
- Souvik Karmakar
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | - Weidong Zhang
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | - Gul Ahmad
- Department of Natural Sciences; School of Arts & Sciences; Peru State College; Peru, NE USA
| | - Mayeen U Alam
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | - Richard Winn
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | | | - Loc Le
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | - Kory A Tillery
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
| | - Afzal A Siddiqui
- Center for Tropical Medicine and Infectious Diseases; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA; Department of Pathology; Texas Tech University Health Sciences Center; Lubbock, TX USA
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Guo P, Dai W, Liu S, Yang P, Cheng J, Liang L, Chen Z, Gao H. Construction and expression of bivalent membrane-anchored DNA vaccine encoding Sjl4FABP and Sj26GST genes. ACTA ACUST UNITED AC 2013; 26:493-6. [PMID: 17219949 DOI: 10.1007/s11596-006-0501-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In order to construct a eukaryotic co-expression plasmid containing membrane-anchored Sjcl4FABP and Sjc26GST genes and identify their expression in vitro, Sj14 and Sj26 genes were obtained by RT-PCR with total RNA of Schistosoma japonicum adult worms as the template and cloned into eukaryotic expression plasmid pVAC to construct recombinant plasmids pVAC-Sj14 and pVAC-Sj26. Then a 23 amino-acid signal peptide of human interleukin-2 (IL-2) upstream Sj14 or Sj26 gene and a membrane-anchored sequence containing 32 amino-acids of carboxyl-terminal of human placental alkaline phosphatase (PLAP) downstream were amplified by PCR as the template of plasmid pVAC-Sj14 or pVAC-Sj26 only to get two gene fragments including Sj14 gene and Sj26 gene. The two modified genes were altogether cloned into a eukaryotic co-expression plasmid pIRES, resulting in another new recombinant plasmid pIRES-Sj26-Sj14. The expression of Sj14 and Sj26 genes was detected by RT-PCR and indirect immunofluorescent assays (IFA) when the plasmid pIRES-Sj26-Sj14 was transfected into eukaryotic Hela cells. Restriction enzyme analysis, PCR and sequencing results revealed that the recombinant plasmids pVAC-Sj14, pVAC-Sj26 and plRES-Sj26-Sj14 were successfully constructed and the expression of modified Sj14 and Sj26 genes could be detected by RT-PCR and IFA. A bivalent membrane-anchored DNA vaccine encoding Sj14 and Sj26 genes was acquired and expressed proteins were proved to be mostly anchored in cellular membranes.
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Affiliation(s)
- Ping Guo
- Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Tongii Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
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Okumura-Noji K, Miura Y, Lu R, Asai K, Ohta N, Brindley PJ, Yokoyama S. CD36-related protein in Schistosoma japonicum: candidate mediator of selective cholesteryl ester uptake from high-density lipoprotein for egg maturation. FASEB J 2012. [PMID: 23195036 DOI: 10.1096/fj.12-219816] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Familial cholesteryl ester transfer protein (CETP) deficiency is more common in some East Asian populations than elsewhere, suggesting the possibility of a selective advantage of this genetic defect against regional infectious diseases. Historically, infection with the Asian blood fluke Schistosoma japonicum has been endemic in these regions, including Japan. We previously reported that eggs of S. japonicum require cholesteryl ester uptake from normal high-density lipoprotein (HDL) but not from CETP-deficient HDL for their maturation to miracidia, a critical step of the hepatic pathogenesis of schistosomiasis. Herein we show that cholesteryl ester uptake is selective from HDL, and identified CD36-related protein (CD36RP) as a candidate to mediate the reaction. CD36RP was cloned from the adult and the egg developmental stages of S. japonicum, with 1880 bp encoding 506 amino acid residues exhibiting the CD36 domains and two transmembrane regions. Using antibodies against recombinant peptides representing the potential extracellular domains of CD36RP, Western blotting detected a protein with a molecular mass of 82 kDa in the particulate fraction of the adult parasite cells, which was reduced to 62 kDa after N-glycanase treatment. The extracellular domain peptide bound human HDL, as established by immunoblots following nondenaturing gel electrophoresis. Antibodies against the extracellular domain suppressed HDL cholesteryl ester uptake and maturation of the eggs in vitro. CD36RP is a candidate receptor on eggs of S. japonicum that facilitates uptake of HDL cholesteryl ester necessary for egg embryonation and maturation.
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Affiliation(s)
- Kuniko Okumura-Noji
- Nutritional Health Science Research Centre and Food and Nutritional Sciences, Chubu University, Kasugai 487-8501, Japan
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Torben W, Ahmad G, Zhang W, Nash S, Le L, Karmakar S, Siddiqui AA. Role of antibody dependent cell mediated cytotoxicity (ADCC) in Sm-p80-mediated protection against Schistosoma mansoni. Vaccine 2012; 30:6753-8. [PMID: 23000221 DOI: 10.1016/j.vaccine.2012.09.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 08/07/2012] [Accepted: 09/10/2012] [Indexed: 10/27/2022]
Abstract
Schistosomiasis is a major health problem in the developing world and for international travelers to the endemic countries. Existing strategies to control schistosomiasis have had limited successes so far. The addition of an effective vaccine in existing control measures would be greatly beneficial in reducing the impact of the disease. In this regard, Sm-p80 mediated protection against intestinal schistosomiasis caused by Schistosoma mansoni has been observed to be promising in two animal models of infection and disease. In this study, the role of antibody dependent cell mediated cytotoxicity (ADCC) was deciphered in Sm-p80-mediated protection especially in the elimination of lung stage schistosomula. This was achieved using lung lavage cells and lung cells that were isolated from mice immunized with and without Sm-p80 formulated in a recombinant vaccine formulation. Significant differences were observed in cytotoxicity assays using immune sera with the lung lavage cells which showed 51% more killing of schistosomula and elevated levels of nitric oxide in the supernatants were detected compared to controls.
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Affiliation(s)
- Workineh Torben
- Center for Tropical Medicine and Infectious Diseases, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Abstract
Schistosomiasis is a major neglected tropical disease of public health importance to a billion people. An estimated 200 million people are currently infected; an additional 779 million individuals are at risk to acquire the infection in 74 countries. Despite many years of implementation of mass anti-parasitic drug therapy programs and other control measures, this disease has not been contained and continues to spread to new geographic areas. The discovery of a protective vaccine still remains the most potentially effective means for the control of this disease, especially if the vaccine provides long-term immunity against the infection. A vaccine would contribute to the reduction of schistosomiasis morbidity through induced immune responses leading to decrease in parasite load and reduced egg production. This vaccine could be administered to children between the ages of 3 and 12 years to prevent severe infection in a particularly high risk population. This review summarizes the current status of schistosomiasis vaccine development.
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Affiliation(s)
- Afzal A Siddiqui
- Department of Microbiology and Immunology, Internal Medicine, Pathology, Texas Tech University Health Sciences Center, Lubbock, TX USA.
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27
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Chen G, Dai Y, Chen J, Wang X, Tang B, Zhu Y, Hua Z. Oral delivery of the Sj23LHD-GST antigen by Salmonella typhimurium type III secretion system protects against Schistosoma japonicum infection in mice. PLoS Negl Trop Dis 2011; 5:e1313. [PMID: 21909450 PMCID: PMC3167783 DOI: 10.1371/journal.pntd.0001313] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Accepted: 07/27/2011] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Schistosomiasis japonica is a zoonotic parasitic disease and oral vaccine delivery system would be benefit for prevention of this disease. Although attenuated salmonella has been used as an antigen expression vector for oral vaccine development, the membrane-bound vacuoles in which bacteria reside hinders the presentation of expressed heterologous antigens to the major histocompatibility complex (MHC) molecules. The present work used an attenuated Salmonella typhimurium strain VNP20009 to secretory expression of Sj23LHDGST bivalent antigen from Schistosoma japonicum and tested the protective efficacy against S. japonicum infection in orally immunized mice. METHODOLOGY/PRINCIPAL FINDINGS Promoters (nirB or pagC) were used to express the antigen (Sj23LHDGST) and the Salmonella type III or α-hemolysin secretion system was employed to secrete it. The immunoblotting analysis and fluorescent microscopy revealed that the antigen was effectively expressed and delivered to the cytosol of macrophages in vitro. Among recombinant vaccine strains, an engineered VNP20009 which expressed the antigen by nirB promoter and secreted it through type III secretion system (nirB-sopE(1-104)-Sj23LHD-GST) efficiently protected against S. japonicum infection in a mouse model. This strain elicited a predominantly IgG(2a) antibody response and a markedly increase in the production of IL-12 and IFN-γ. The flow cytometric analysis demonstrated that this strain caused T cell activation as evidenced by significantly increased expression of CD44 and CD69. CONCLUSION/SIGNIFICANCE Oral delivery of antigen by nirB-driven Salmonella typhimurium type III secretion system is a novel, safe, inexpensive, efficient and convenient approach for schistosome vaccine development.
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MESH Headings
- Administration, Oral
- Animals
- Antibodies, Helminth/blood
- Antigens, Helminth/genetics
- Antigens, Helminth/immunology
- Bacterial Vaccines/administration & dosage
- Bacterial Vaccines/adverse effects
- Bacterial Vaccines/genetics
- Bacterial Vaccines/immunology
- Disease Models, Animal
- Feces/parasitology
- Female
- Genetic Vectors
- Granuloma/pathology
- Granuloma/prevention & control
- Immunoglobulin G/blood
- Interferon-gamma/metabolism
- Interleukin-12/metabolism
- Macrophages/immunology
- Mice
- Mice, Inbred BALB C
- Parasite Egg Count
- Salmonella typhimurium/genetics
- Schistosoma japonicum/genetics
- Schistosoma japonicum/immunology
- Schistosomiasis japonica/immunology
- Schistosomiasis japonica/pathology
- Schistosomiasis japonica/prevention & control
- Vaccination/methods
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/adverse effects
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
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Affiliation(s)
- Guo Chen
- The State Key Laboratory of Pharmaceutical Biotechnology and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing, People's Republic of China
| | - Yang Dai
- Key Laboratory on Technology for Parasitic Diseases Prevention and Control, Ministry of Health and Jiangsu Provincial Key Laboratory on Molecular Biology of Parasites, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, People's Republic of China
| | - Jianxiang Chen
- The State Key Laboratory of Pharmaceutical Biotechnology and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing, People's Republic of China
| | - Xiaoting Wang
- Key Laboratory on Technology for Parasitic Diseases Prevention and Control, Ministry of Health and Jiangsu Provincial Key Laboratory on Molecular Biology of Parasites, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, People's Republic of China
| | - Bo Tang
- The State Key Laboratory of Pharmaceutical Biotechnology and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing, People's Republic of China
| | - Yinchang Zhu
- Key Laboratory on Technology for Parasitic Diseases Prevention and Control, Ministry of Health and Jiangsu Provincial Key Laboratory on Molecular Biology of Parasites, Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu, People's Republic of China
- * E-mail: (ZH); (YZ)
| | - Zichun Hua
- The State Key Laboratory of Pharmaceutical Biotechnology and School of Stomatology, Affiliated Stomatological Hospital, Nanjing University, Nanjing, People's Republic of China
- Changzhou High-Tech Research Institute of Nanjing University and Changzhou TargetPharma Laboratories Inc., Changzhou, People's Republic of China
- * E-mail: (ZH); (YZ)
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Zhang W, Ahmad G, Torben W, Siddiqui AA. Sm-p80-based DNA vaccine made in a human use approved vector VR1020 protects against challenge infection with Schistosoma mansoni in mouse. Parasite Immunol 2010; 32:252-8. [PMID: 20398225 DOI: 10.1111/j.1365-3024.2009.01181.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although there is an effective drug (praziquantel) available for the treatment of schistosomiasis, yet the disease is still spreading unabated and is rampant in 76 countries. Control via praziquantel treatment has so far been insufficient in reducing the disease transmission. Therefore, a vaccine in addition to other strategies, for example, improving sanitation and introduction of new drugs are essential to successfully control and eventually eradicate schistosomiasis. To this effect, we have targeted a functionally important antigen, Sm-p80 as a vaccine candidate. In this study, full length cDNA of Sm-p80 was cloned in VR1020, a FDA approved vector for human use. The protective efficacy of this vaccine formulation was tested in a murine model. Sm-p80-VR1020 vaccine formulation was able to induce 47% reduction in worm burden. Serology on samples obtained from vaccinated animals revealed a strong antibody response which included IgG and all of its subtypes, IgM and IgA. Proliferating splenocytes in response to recombinant Sm-p80 produced a wide spectrum of cytokines representing Th1, Th2 and Th17 types, as ascertained via RT-PCR analysis. These findings further strengthen the importance of Sm-p80 molecule as a vaccine candidate for intestinal schistosomiasis.
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Affiliation(s)
- W Zhang
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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29
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Zhang W, Ahmad G, Torben W, Noor Z, Le L, Damian RT, Wolf RF, White GL, Chavez-Suarez M, Podesta RB, Kennedy RC, Siddiqui AA. Sm-p80-based DNA vaccine provides baboons with levels of protection against Schistosoma mansoni infection comparable to those achieved by the irradiated cercarial vaccine. J Infect Dis 2010; 201:1105-12. [PMID: 20187746 DOI: 10.1086/651147] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To date, no vaccine is available to prevent human schistosomiasis. We have targeted a protein of Schistosoma mansoni that plays an important role in the surface membrane renewal process, a mechanism widely believed to be utilized by the parasite as an immune evasion strategy. Sm-p80 antigen is a promising vaccine target because of its documented immunogenicity, protective efficacy, and antifecundity effects observed in both experimental murine and nonhuman primate models of this infectious disease. In the present study, we report that, in a vector approved for human use (VR1020), an Sm-p80-based DNA vaccine formulation confers a 46% reduction in the worm burden in a baboon (Papio anubis) model. Baboons vaccinated with Sm-p80-VR1020 had a 28% decrease in egg production after challenge with the infectious parasite. Sm-p80-VR1020 vaccine elicited robust immune responses to specific antigen Sm-p80, including immunoglobulin (Ig) G, its subtypes IgG1 and IgG2, and IgA and IgM in vaccinated animals. When stimulated in vitro with recombinant Sm-p80, peripheral blood mononuclear cells and splenocytes from baboons vaccinated with Sm-p80-VR1020 produced considerably higher levels of T helper 1 response-enhancing cytokines (interleukin [IL]-2 and interferon-gamma) than T helper 2 (Th2) response-enhancing cytokines (IL-4 and IL-10). Peripheral blood mononuclear cells produced a significantly higher number of spot-forming units for interferon-gamma than for IL-4 in enzyme-linked immunosorbent spot assays. A mixed T helper 1/T helper 2 type of humoral and T cell responses was generated after immunization with Sm-p80-VR1020. These findings again highlight the potential of Sm-p80 as a promising vaccine candidate for schistosomiasis.
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Affiliation(s)
- Weidong Zhang
- Department of 1Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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Schistosoma mansoni Stomatin like protein-2 is located in the tegument and induces partial protection against challenge infection. PLoS Negl Trop Dis 2010; 4:e597. [PMID: 20161725 PMCID: PMC2817717 DOI: 10.1371/journal.pntd.0000597] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Accepted: 12/14/2009] [Indexed: 12/27/2022] Open
Abstract
Background Schistosomiasis affects more than 200 million individuals worldwide, with a further 650 million living at risk of infection, constituting a severe health problem in developing countries. Even though an effective treatment exists, it does not prevent re-infection, and the development of an effective vaccine still remains the most desirable means of control for this disease. Methodology/Principal Findings Herein, we report the cloning and characterization of a S. mansoniStomatin-like protein 2 (SmStoLP-2). In silico analysis predicts three putative sites for palmitoylation (Cys11, Cys61 and Cys330), which could contribute to protein membrane association; and a putative mitochondrial targeting sequence, similar to that described for human Stomatin-like protein 2 (HuSLP-2). The protein was detected by Western blot with comparable levels in all stages across the parasite life cycle. Fractionation by differential centrifugation of schistosome tegument suggested that SmStoLP-2 displays a dual targeting to the tegument membranes and mitochondria; additionally, immunolocalization experiments confirm its localization in the tegument of the adult worms and, more importantly, in 7-day-old schistosomula. Analysis of the antibody isotype profile to rSmStoLP-2 in the sera of patients living in endemic areas for schistosomiasis revealed that IgG1, IgG2, IgG3 and IgA antibodies were predominant in sera of individuals resistant to reinfection as compared to those susceptible. Next, immunization of mice with rSmStoLP-2 engendered a 30%–32% reduction in adult worm burden. Protective immunity in mice was associated with specific anti-rSmStoLP-2 IgG1 and IgG2a antibodies and elevated production of IFN-γ and TNF-α, while no IL-4 production was detected, suggesting a Th1-predominant immune response. Conclusions/Significance Data presented here demonstrate that SmStoLP-2 is a novel tegument protein located in the host-parasite interface. It is recognized by different subclasses of antibodies in patients resistant and susceptible to reinfection and, based on the data from murine studies, shows protective potential against schistosomiasis. These results indicate that SmStoLP-2 could be useful in a combination vaccine. Schistosomiasis is a parasitic disease causing serious chronic morbidity in tropical countries. Together with the publication of the transcriptome database, a series of new vaccine candidates were proposed based on their functional classification. However, the prediction of vaccine candidates from sequence information or even by proteomics or microarrays data is somewhat speculative and there remains the considerable task of functional analysis of each new gene/protein. In this study, we present the characterization of one of these molecules, a stomatin like protein 2 (SmStoLP-2). Sequence analysis predicts signals that could contribute to protein membrane association and mitochondrial targeting, which was confirmed by differential extractions of schistosome tegument membranes and mitochondria. Additionally, confocal microscope analysis showed SmStoLP-2 present in the tegument of 7-day-old schistosomula and adult worms. Studies in patients living in endemic areas for schistosomiasis revealed high levels of IgG1, IgG2, IgG3 and IgA anti-SmStoLP-2 antibodies in individuals resistant to reinfection. Recombinant SmStoLP-2 protein, when used as vaccine, induced significant levels of protection in mice. This reduction in worm burden was associated with a typical Th1-type immune response. These results indicate that SmStoLP-2 could be useful in association with other antigens for the composition of a vaccine against schistosomiasis.
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Bos DH, Mayfield C, Minchella DJ. Analysis of regulatory protease sequences identified through bioinformatic data mining of the Schistosoma mansoni genome. BMC Genomics 2009; 10:488. [PMID: 19845954 PMCID: PMC2772863 DOI: 10.1186/1471-2164-10-488] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Accepted: 10/21/2009] [Indexed: 11/20/2022] Open
Abstract
Background New chemotherapeutic agents against Schistosoma mansoni, an etiological agent of human schistosomiasis, are a priority due to the emerging drug resistance and the inability of current drug treatments to prevent reinfection. Proteases have been under scrutiny as targets of immunological or chemotherapeutic anti-Schistosoma agents because of their vital role in many stages of the parasitic life cycle. Function has been established for only a handful of identified S. mansoni proteases, and the vast majority of these are the digestive proteases; very few of the conserved classes of regulatory proteases have been identified from Schistosoma species, despite their vital role in numerous cellular processes. To that end, we identified protease protein coding genes from the S. mansoni genome project and EST library. Results We identified 255 protease sequences from five catalytic classes using predicted proteins of the S. mansoni genome. The vast majority of these show significant similarity to proteins in KEGG and the Conserved Domain Database. Proteases include calpains, caspases, cytosolic and mitochondrial signal peptidases, proteases that interact with ubiquitin and ubiquitin-like molecules, and proteases that perform regulated intramembrane proteolysis. Comparative analysis of classes of important regulatory proteases find conserved active site domains, and where appropriate, signal peptides and transmembrane helices. Phylogenetic analysis provides support for inferring functional divergence among regulatory aspartic, cysteine, and serine proteases. Conclusion Numerous proteases are identified for the first time in S. mansoni. We characterized important regulatory proteases and focus analysis on these proteases to complement the growing knowledge base of digestive proteases. This work provides a foundation for expanding knowledge of proteases in Schistosoma species and examining their diverse function and potential as targets for new chemotherapies.
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Affiliation(s)
- David H Bos
- Department of Biological Sciences, Purdue University, 915 W State St, West Lafayette, IN 47907, USA.
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Ahmad G, Zhang W, Torben W, Haskins C, Diggs S, Noor Z, Le L, Siddiqui AA. Prime-boost and recombinant protein vaccination strategies using Sm-p80 protects against Schistosoma mansoni infection in the mouse model to levels previously attainable only by the irradiated cercarial vaccine. Parasitol Res 2009; 105:1767-77. [PMID: 19809833 DOI: 10.1007/s00436-009-1646-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Accepted: 09/23/2009] [Indexed: 12/17/2022]
Abstract
Advent of an effective schistosome vaccine would contribute significantly toward reducing the disease spectrum and transmission of schistosomiasis. We have targeted a functionally important antigen, Sm-p80, as a vaccine candidate because of its consistent immunogenicity, protective and antifecundity potentials, and important role in the immune evasion process. In this study, we report that using two vaccination approaches (prime boost and recombinant protein), Sm-p80-based vaccine formulation(s) confer up to 70% reduction in worm burden in mice. Animals immunized with the vaccine exhibited a decrease in egg production by up to 75%. The vaccine elicited strong immune responses that included IgM, IgA, and IgG (IgG1, IgG2a, IgG2b, and IgG3) in vaccinated animals. Splenocytes proliferated in response to Sm-p80 produced Th1 and Th17 response enhancing cytokines. These results again emphasize the potential of Sm-p80 as a viable vaccine candidate for schistosomiasis.
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Affiliation(s)
- Gul Ahmad
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA
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33
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Xu X, Zhang D, Sun W, Zhang Q, Zhang J, Xue X, Shen L, Pan W. A Schistosoma japonicum chimeric protein with a novel adjuvant induced a polarized Th1 immune response and protection against liver egg burdens. BMC Infect Dis 2009; 9:54. [PMID: 19419545 PMCID: PMC2685138 DOI: 10.1186/1471-2334-9-54] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Accepted: 05/06/2009] [Indexed: 11/11/2022] Open
Abstract
Background Schitosomiasis japonica is still a significant public health problem in China. A protective vaccine for human or animal use represents an important strategy for long-term control of this disease. Due to the complex life cycle of schistosomes, different vaccine design approaches may be necessary, including polyvalent subunit vaccines. In this study, we constructed four chimeric proteins (designated SjGP-1~4) via fusion of Sj26GST and four individual paramyosin fragments. We tested these four proteins as vaccine candidates, and investigated the effect of deviating immune response on protection roles in mice. Methods The immunogencity and protection efficacy of chimeric proteins were evaluated in mice. Next, the chimeric protein SjGP-3 was selected and formulated in various adjuvants, including CFA, ISA 206, IMS 1312 and ISA 70M. The titers of antigen-specific IgG, IgE and IgG subclass were measured. The effect of adjuvant on cytokine production and percentages of CD3+CD8-IFN-γ+ cells and CD3+CD8-IL-4+ cells were analyzed at different time points. Worm burdens and liver egg counts in different adjuvant groups were counted to evaluate the protection efficacy against cercarial challenge. Results Immunization of mice with chimeric proteins provided various levels of protection. Among the four proteins, SjGP-3 induced the highest level of protection, and showed enhanced protective efficacy compared with its individual component Sj26GST. Because of this, SjGP-3 was further formulated in various adjuvants to investigate the effect of adjuvant on immune deviation. The results revealed that SjGP-3 formulated in veterinary adjuvant ISA 70M induced a lasting polarized Th1 immune response, whereas the other adjuvants, including CFA, ISA 206 and IMS 1312, generated a moderate mixed Th1/Th2 response after immunization but all except for IMS 1312 shifted to Th2 response after onset of eggs. More importantly, the SjGP-3/70M formulation induced a significant reduction in liver egg deposition at 47.0–50.3% and the number of liver eggs per female at 34.5–37.2% but less effect on worm burdens at only 17.3–23.1%, whereas no effect of the formulations with other adjuvants on the number of liver eggs per female was observed. Conclusion Construction of polyvalent subunit vaccine was capable to enhance immunogenicity and protection efficacy against schistosomiasis. There was correlation of the polarized Th1 response with reduction of liver egg burdens, supporting the immune deviation strategy for schistosomiasis japonica vaccine development.
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Affiliation(s)
- Xindong Xu
- Institute for Infectious Diseases & Vaccine Development, Tongji University School of Medicine, 1239 Siping Road, Shanghai 200092, PR China.
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Ahmad G, Torben W, Zhang W, Wyatt M, Siddiqui AA. Sm-p80-based DNA vaccine formulation induces potent protective immunity against Schistosoma mansoni. Parasite Immunol 2009; 31:156-61. [PMID: 19222788 DOI: 10.1111/j.1365-3024.2008.01091.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
No effective vaccine exists for the human parasitic disease, schistosomiasis. We have targeted a functionally important antigen, Sm-p80 as a vaccine candidate because of its consistent immunogenicity, protective potential and important role in the immune evasion process. In this study we report that a Sm-p80-based DNA vaccine formulation confers 59% reduction in worm burden in mice. Animals immunized with Sm-p80-pcDNA3 exhibited a decrease in egg production by 84%. Sm-p80 DNA elicited strong immune responses that include IgG2A and IgG2B antibody isotypes in vaccinated animals. Splenocytes proliferated in response to Sm-p80 produced appreciably more Th1 response enhancing cytokines (IL-2, IFN-gamma) than Th2 response enhancing cytokines (IL-4, IL-10). These data reinforce the potential of Sm-p80 as an excellent vaccine candidate for schistosomiasis.
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Affiliation(s)
- G Ahmad
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, Lubbock, 79430, USA
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Ahmad G, Zhang W, Torben W, Damian RT, Wolf RF, White GL, Chavez-Suarez M, Kennedy RC, Siddiqui AA. Protective and antifecundity effects of Sm-p80-based DNA vaccine formulation against Schistosoma mansoni in a nonhuman primate model. Vaccine 2009; 27:2830-7. [PMID: 19366570 DOI: 10.1016/j.vaccine.2009.02.096] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 02/19/2009] [Accepted: 02/24/2009] [Indexed: 12/26/2022]
Abstract
Schistosomiasis is an important parasitic disease for which there is no available vaccine. We have focused on a functionally important antigen of Schistosoma mansoni, Sm-p80, as a vaccine candidate because of its consistent immunogenicity, protective potential and antifecundity effect observed in murine models; and for its pivotal role in the immune evasion process. In the present study we report that an Sm-p80-based DNA vaccine formulation confers 38% reduction in worm burden in a nonhuman primate model, the baboon (Papio anubis). Animals immunized with Sm-p80-pcDNA3 exhibited a decrease in egg production by 32%. Sm-p80 DNA elicited specific immune responses that include IgG; its subtypes IgG1 and IgG2; and IgM in vaccinated animals. Peripheral blood mononuclear cells (PBMCs) from immunized animals when stimulated in vitro with Sm-p80 produced appreciably more Th1 response enhancing cytokines (IL-2, IFN-gamma) than Th2 response enhancing cytokines (IL-4, IL-10). PBMCs produced appreciably more spot-forming units for INF-gamma than for IL-4 in enzyme-linked immunosorbent spot (ELISPOT) assays. Overall it appears that even though a mixed (Th1/Th2) type of humoral antibody response was generated following immunization with Sm-p80; the dominant protective immune response is Th1 type. These data reinforce the potential of Sm-p80 as an excellent vaccine candidate for schistosomiasis.
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Affiliation(s)
- Gul Ahmad
- Department of Microbiology, Texas Tech University Health Sciences Center, Lubbock, TX 79430, United States
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Siddiqui AA, Ahmad G, Damian RT, Kennedy RC. Experimental vaccines in animal models for schistosomiasis. Parasitol Res 2008; 102:825-33. [PMID: 18259777 DOI: 10.1007/s00436-008-0887-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 01/13/2008] [Indexed: 01/06/2023]
Abstract
Considerable morbidity and mortality results from the affliction of an estimated 200 million people worldwide by several species of schistosomes; 779 million are exposed to the disease in 74 different countries. Even though anti-parasitic drugs and other control measures, including public hygiene and snail control are available, the advent of an effective vaccine still remains the most potentially powerful means for the control of this disease. The putative vaccine could be administered to small children prior to the time when their contact with infected water is maximal, so as to prevent severe infection in the subsequent years. This review attempts to summarize the status of schistosome vaccine development with special emphasis on functionally important vaccine candidates. The importance of utilizing both murine and nonhuman primate models as a prerequisite for clinical trials is discussed.
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Affiliation(s)
- Afzal A Siddiqui
- Department of Microbiology and Immunology, Texas Tech University Health Sciences Center, 3601 4th Street, Stop 6591, Lubbock, TX 79430-6591, USA.
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Ohta N, Waikagul J. Disease burden and epidemiology of soil-transmitted helminthiases and schistosomiasis in Asia: the Japanese perspective. Trends Parasitol 2007; 23:30-5. [PMID: 17134942 DOI: 10.1016/j.pt.2006.11.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 09/18/2006] [Accepted: 11/15/2006] [Indexed: 10/23/2022]
Abstract
The disease burden due to soil-transmitted helminthiases (STH) and schistosomiasis is not well documented in Asia. Both STH and schistosomiasis are chronic diseases but case detection is not easy because of the absence of clinical symptoms. STH and schistosomiasis are, however, endemic in Asia and their burden is significant. At the preparatory meeting for the Hashimoto Initiative in Japan in 1997, STH and schistosomiasis were categorized as Group 2 diseases. Parasitic infections in this category were well understood at the time but sophisticated control strategies were lacking. Japan has promoted comprehensive collaborative projects to reduce the burden of STH and schistosomiasis throughout Asia, creating an international network to collect epidemiological information and to implement and improve disease control, thus extending the school-based control method that had proved so successful in Japan.
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Affiliation(s)
- Nobuo Ohta
- Section of Environmental Parasitology, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
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38
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Vaccination with Setaria cervi 175 kDa collagenase induces high level of protection against Brugia malayi infection in jirds. Vaccine 2006; 24:6208-15. [PMID: 16870314 DOI: 10.1016/j.vaccine.2006.05.103] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 05/27/2006] [Accepted: 05/29/2006] [Indexed: 11/20/2022]
Abstract
A zinc containing metalloprotease, 175 kDa collagenase, purified from adult female Setaria cervi showed strong cross-reactivity with sera from putatively immune (PI) individuals (unpublished observation) and induced cytotoxicity to B. malayi L3 larvae and microfilariae by ADCC mechanism [Srivastava Y, Bhandari YP, Reddy MVR, Harinath BC, Rathaur S. An adult 175 kDa collagenase antigen of Setaria cervi in immunoprophylaxis against Brugia malayi. J Helminth 2004;78:347-52]. These preliminary observations suggested the immunoprotective nature of collagenase. To confirm the vaccine potential of this protease, a vaccine trial was conducted in jirds (Meriones unguiculatus) against human filarial parasite B. malayi. The vaccination resulted into a mean protection level of 75.86% and produced high level of protease neutralizing antibodies. Cytokine analysis in immune jirds sera suggested a mixed Th1/Th2 type cellular immune response whereas ELISA, immunoblotting and enzyme antibody inhibition assay revealed the presence of specific anti-collagenase antibodies. Taken together, all these results suggest that S. cervi 175 kDa collagenase could form the basis of an effective molecular vaccine against human lymphatic filariasis.
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POKHAREL DR, RATHAUR S. Helminth proteases: the leading vaccine candidates against helminth infections. Parasite Immunol 2006. [DOI: 10.1111/j.1365-3024.2006.00855.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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40
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Lee JS, Kim IS, Sohn WM, Lee J, Yong TS. Vaccination with DNA encoding cysteine proteinase confers protective immune response to rats infected with Clonorchis sinensis. Vaccine 2006; 24:2358-66. [PMID: 16406168 DOI: 10.1016/j.vaccine.2005.11.062] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 11/18/2005] [Accepted: 11/24/2005] [Indexed: 11/17/2022]
Abstract
Cysteine proteinases of C. sinensis are important virulence factors that induce pathological changes associated with larval migration and localized biliary epithelial destruction. This study investigated the immunogenicity and protective efficacy of a DNA vaccine encoding Clonorchis sinensis cysteine proteinase (CsCP). The CsCP cDNA sequence displays significant homology to the mammalian or trematode cathepsin L. Plasmid DNA carrying the CsCP gene (pcDNA3.1-CsCP) was injected into Sprague-Dawley (SD) rats intradermally. Animals injected with pcDNA3.1-CsCP developed CsCP-specific antibodies, which exhibited an IgG2a dominance in sera. In addition, the DNA vaccine elicited the production of IFN-gamma, but not IL-4 in splenocytes, suggesting the induction of a typical Th-1 dominated immune response in rats. The pcDNA3.1-CsCP induced a significant level of protection (31.5%, p<0.05) in SD rats challenged with C. sinensis metacercariae. These results indicate that pcDNA3.1-CsCP induces both humoral and cellular immune responses. The CsCP gene may be a good candidate for use in future studies of vaccination against clonorchiasis.
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Affiliation(s)
- Ji-Sook Lee
- Department of Biology, Daejeon University, Daejeon 300-716, South Korea
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41
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Kong WP, Xu L, Stadler K, Ulmer JB, Abrignani S, Rappuoli R, Nabel GJ. Modulation of the immune response to the severe acute respiratory syndrome spike glycoprotein by gene-based and inactivated virus immunization. J Virol 2006; 79:13915-23. [PMID: 16254327 PMCID: PMC1280202 DOI: 10.1128/jvi.79.22.13915-13923.2005] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although the initial isolates of the severe acute respiratory syndrome (SARS) coronavirus (CoV) are sensitive to neutralization by antibodies through their spike (S) glycoprotein, variants of S have since been identified that are resistant to such inhibition. Optimal vaccine strategies would therefore make use of additional determinants of immune recognition, either through cellular or expanded, cross-reactive humoral immunity. Here, the cellular and humoral immune responses elicited by different combinations of gene-based and inactivated viral particles with various adjuvants have been assessed. The T-cell response was altered by different prime-boost immunizations, with the optimal CD8 immunity induced by DNA priming and replication-defective adenoviral vector boosting. The humoral immune response was enhanced most effectively through the use of inactivated virus with adjuvants, either MF59 or alum, and was associated with stimulation of the CD4 but not the CD8 response. The use of inactivated SARS virus with MF59 enhanced the CD4 and antibody response even after gene-based vaccination. Because both cellular and humoral immune responses are generated by gene-based vaccination and inactivated viral boosting, this strategy may prove useful in the generation of SARS-CoV vaccines.
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Affiliation(s)
- Wing-pui Kong
- Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bldg. 40, Room 4502, MSC-3005, 40 Convent Drive, Bethesda, Maryland 20892-3005, USA
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Li GF, Wang Y, Zhang ZS, Wang XJ, Ji MJ, Zhu X, Liu F, Cai XP, Wu HW, Wu GL. Identification of immunodominant Th1-type T cell epitopes from Schistosoma japonicum 28 kDa glutathione-S-transferase, a vaccine candidate. Acta Biochim Biophys Sin (Shanghai) 2005; 37:751-8. [PMID: 16270154 DOI: 10.1111/j.1745-7270.2005.00111.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Th1-type cytokines produced by the stimulation of Th1-type epitopes derived from defined schistosome-associated antigens are correlated with the development of resistance to the parasite infection. Schistosoma mansoni 28 kDa glutathione-S-transferase (Sm28GST), a major detoxification enzyme, has been recognized as a vaccine candidate and a phase II clinical trial has been carried out. Sheep immunized with recombinant Schistosoma japonicum 28GST (Sj28GST) have shown immune protection against the parasite infection. In the present study, six candidate peptides (P1, P2, P3, P4, P7 and P8) from Sj28GST were predicted, using software, to be T cell epitopes, and peptides P5 and P6 were designed by extending five amino acids at the N-terminal and C-terminal of P1, respectively. The peptide 190-211 aa in Sj28GST corresponding to the Th1-type epitope (190-211 aa) identified from Sm28GST was selected and named P9. The nine candidate peptides were synthesized or produced as the fusion protein with thioredoxin in the pET32c(+)/BL21(DE3) system. Their capacity to induce a Th1-type response in vitro was measured using lymphocyte proliferation, cytokine detection experiments and flow cytometry. The results showed that P6 (73-86 aa) generated the strongest stimulation effect on T cells among the nine candidate peptides, and drove the highest level of IFN-gamma and IL-2. Therefore, P6 is a functional Th1-type T cell epitope that is different from that in Sm28GST, and will be useful for the development of effective vaccines which can trigger acquired immunity against S. japonicum. Moreover, our strategy of identifying the Th1-type epitope by a combination of software prediction and experimental confirmation provides a convenient and cost-saving alternative approach to previous methods.
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Affiliation(s)
- Guang-Fu Li
- Department of Pathogenic Biology, Nanjing Medical University, Nanjing 210029, China
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43
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McManus DP. Prospects for development of a transmission blocking vaccine against Schistosoma japonicum. Parasite Immunol 2005; 27:297-308. [PMID: 16138851 DOI: 10.1111/j.1365-3024.2005.00784.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Despite intensive long-term control programmes, schistosomiasis japonica remains a serious public health problem in China and the Philippines. The termination of mass praziquantel-treatment has seen a dramatic recent rebound in both its prevalence and associated morbidity. Schistosomiasis japonica is a zoonosis but, despite complicating control efforts, this feature provides a practical method for attacking Schistosoma japonicum through development and deployment of a transmission blocking veterinary vaccine. A recently completed bovine drug intervention trial and mathematical modelling of the transmission of S. japonicum underpin the concept that such a vaccine, targeting water buffalo, would have major implications for future integrated schistosomiasis control in China. A major block to success is the low ceiling efficacy achieved with current vaccine molecules. To solve this challenge, an antigen discovery pipeline needs to be established for identification of new vaccine targets that induce greater potency than the current anti-S. japonicum candidate vaccines. Excretory-secretory products and molecules exposed on epithelial surfaces (including receptors) which interact directly with the host immune system warrant especial attention. Extensive schistosome genomics programmes currently underway coupled with new advances in proteomics and microarray technology provide an unparalleled opportunity to identify new molecules exploitable as vaccine targets. These will then need to be produced in quantity and rigorously tested first in the laboratory and then the field. If a transmission blocking veterinary vaccine developed for bovines can be put into practice in combination with other control strategies such as human chemotherapy, elimination of S. japonicum from China may be achievable.
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Affiliation(s)
- D P McManus
- Molecular Parasitology Laboratory, Queensland Institute of Medical Research, Brisbane, Australia.
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Osada Y, Kumagai T, Hato M, Suzuki T, El-Malky M, Asahi H, Kanazawa T, Ohta N. Establishment of Schistosoma japonicum calpain-specific mouse T cell hybridomas and identification of a T cell epitope that stimulates IFNγ production. Vaccine 2005; 23:2813-9. [PMID: 15780729 DOI: 10.1016/j.vaccine.2004.10.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2004] [Revised: 10/14/2004] [Accepted: 10/19/2004] [Indexed: 11/17/2022]
Abstract
Calpain is a calcium-dependent cystein protease, and the homologues of schistosome are known as one of vaccine candidate molecules against schistosomiasis. Here, we established two IL-2 producing T cell hybridoma cell lines specific for Schistosoma japonicum calpain, to identify T cell epitope(s) on the molecule. Overlapping 15mer oligopeptides of calpain were synthesized and tested for their stimulatory abilities to the hybridomas. As a result, epitopes recognized by the two hybridoma lines were the same: EQLKIYAQRC. Spleen cells from calpain multiple antigenic peptide (MAP)-immunized BALB/c mice produced IFNgamma upon stimulation with MAP or soluble worm antigen preparation (SWAP). The identification of the T cell epitope to stimulate Th1 response will contribute to the proper design of synthetic vaccines, evaluation of their protective potentials and elucidation of protective mechanisms in murine experimental schistosomiasis.
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Affiliation(s)
- Yoshio Osada
- Department of Parasitology and Tropical Public Health, The University of Occupational and Environmental Health, Japan, Kitakyushu 807-8555, Japan.
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Siddiqui AA, Pinkston JR, Quinlin ML, Saeed Q, White GL, Shearer MH, Kennedy RC. Characterization of the immune response to DNA vaccination strategies for schistosomiasis candidate antigen, Sm-p80 in the baboon. Vaccine 2005; 23:1451-6. [PMID: 15670880 DOI: 10.1016/j.vaccine.2004.09.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 08/27/2004] [Accepted: 09/28/2004] [Indexed: 10/26/2022]
Abstract
Even though schistosomicidal agents and other control measures, including public hygiene and snail control exist, development of an efficacious vaccine still remains the most potentially powerful method for control of schistosomiasis. In our continuing efforts to develop a vaccine against schistosomiasis, we have selected a vaccine candidate (Sm-p80), which plays an important role in the immune evasion process of the parasite. Sm-p80 has been shown to confer up to 60% protection in mice following experimental infection. In this initial study, we have used Sm-p80 plus the Th1 response promoting cytokine, interleukin-2 (IL-2), in a DNA immunogen formulation. The vaccine was tested for its safety and immunogenicity in a baboon model of schistosomiasis. The vaccine generated a Th1 type Sm-p80-specific response in baboons with IgG(1)/IgG(2) ratios of less than 1.0. No detectable IgG(3) or IgG(4) anti-Sm-p80 responses were present in the immunized baboons. The antibodies to Sm-p80 were able to kill up to 35% schistosomula in vitro in the presence of complement. These results although preliminary suggest the potential of Sm-p80 as a viable vaccine candidate for schistosomiasis.
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Affiliation(s)
- Afzal A Siddiqui
- Department of Internal Medicine, Texas Tech Women's Health and Research Institute, 1400 Wallace Blvd., Amarillo, TX 79106-1791, USA.
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Kumagai T, Maruyama H, Hato M, Ohmae H, Osada Y, Kanazawa T, Ohta N. Schistosoma japonicum: localization of calpain in the penetration glands and secretions of cercariae. Exp Parasitol 2005; 109:53-7. [PMID: 15639140 DOI: 10.1016/j.exppara.2004.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Revised: 10/29/2004] [Accepted: 11/02/2004] [Indexed: 11/29/2022]
Abstract
A monoclonal antibody was generated against the large subunit of Schistosoma japonicum calpain to study the localization and possible function of the molecule in vivo. Mice were immunized with recombinant S. japonicum calpain and polyclonal antisera and a monoclonal antibody specific to schistosome calpain was obtained. In immunohistochemistry, a monoclonal antibody against S. japonicum calpain, KG-2E11, bound weakly to calpain expressed at the surface of adult worm tegument, however, it bound strongly to the cercarial secretions ("footprints") of S. japonicum, emitted from the penetration glands. The present study indicates that calpain is multifunctional as it is expressed at various locations in different developmental stages. Calpain-based vaccines could thus possibly induce protective immunity against cercariae and the following early developing stages.
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Affiliation(s)
- Takashi Kumagai
- Department of Parasitology and Tropical Public Health, The University of Occupational and Environmental Health Japan, Kitakyusyu, Japan.
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47
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Ohta N, Kumagai T, Maruyama H, Yoshida A, He Y, Zhang R. Research on calpain of Schistosoma japonicum as a vaccine candidate. Parasitol Int 2004; 53:175-81. [PMID: 15081949 DOI: 10.1016/j.parint.2004.01.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Vaccine development by the use of calpain of Schistosoma japonicum has been tried in our laboratory. We cloned cDNA encoding the heavy chain of S. japonicum calpain, and prepared recombinant molecule of a possible vaccine region of the heavy chain. When BALB/c mice were immunized with our recombinant calpain of S. japonicum with Freund's complete adjuvant, we observed significant reduction in worm burden (41.2% reduction, P<0.05), and also significant anti-fecundity effects. In this sense, calpain of S. japonicum seems to have infection control as well as anti-disease effects. Mechanisms of vaccine effects of calpain remain to be clarified, however, several effector mechanisms are suspected. In immunized mice, raised level of iNos expression was observed, while adhesion of peritoneal exudates cells were also observed in the presence of calpain-immunized sera, suggesting the possibilities of both cellular and humoral protective mechanisms. We examined tissue distribution of calpain in various developmental stages of S. japonicum. Strong signal was observed around excretory grand of cercariae, and they secreted calpain during their migratory movement tested in vitro. Together with the findings, calpain seems to induce larvicidal effects in the immunized mice. We observed time-course kinetics of antibody production against vaccine candidates in experimental S. japonicum infection in pigs. Although significant levels of antibody production were observed for paramyosin and GST, no significant antibody production was observed for calpain. This suggests that calpain is less immunogenic, and route of immunization and/or choice of adjuvant are important in future trials of calpain vaccine.
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Affiliation(s)
- Nobuo Ohta
- Department of Molecular Parasitology, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan.
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Abstract
There is continued transmission of schistosomiasis japonica in China and Philippines despite highly effective control programs that focus on the application of the highly effective drug praziquantel (PZQ). The massive Three Gorges Dam across the Yangtze River in Southern China, soon to be completed, is expected to significantly increase schistosomiasis transmission and introduce the disease into areas currently unaffected. After long-term experience it is generally accepted that PZQ chemotherapy, although the cornerstone of current control programs, does have significant limitations. Furthermore, efficient drug delivery requires a substantial infrastructure to regularly cover all parts of an endemic area. Although there is not yet clear-cut evidence for the existence of PZQ-resistant schistosome strains, decreased susceptibility to the drug has been observed in several countries. As a result, a protective vaccine represents an essential component for the long-term control of schistosomiasis. This article briefly reviews aspects of anti-schistosome protective immunity that are important in the context of vaccine development. The current status in the development of vaccines against Schistosoma japonicum will then be discussed as will new approaches that may improve on the efficacy of available vaccines, and aid in the identification of new targets for immune attack. With new and extensive data becoming available from the S. japonicum genome project, the prospects for developing an effective vaccine are encouraging. The challenges that remain are many but it is crucial that the momentum towards developing effective anti-schistosome vaccines is maintained.
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Affiliation(s)
- Donald P McManus
- Molecular Parasitology Laboratory, Australian Center for International and Tropical Health and Nutrition, Queensland Institute of Medical Research, 300 Herston Road, Brisbane, QLD 4029, Australia.
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49
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Siddiqui AA, Phillips T, Charest H, Podesta RB, Quinlin ML, Pinkston JR, Lloyd JD, Paz M, Villalovos RM, Pompa J. Induction of protective immunity against Schistosoma mansoni via DNA priming and boosting with the large subunit of calpain (Sm-p80): adjuvant effects of granulocyte-macrophage colony-stimulating factor and interleukin-4. Infect Immun 2003; 71:3844-51. [PMID: 12819068 PMCID: PMC161986 DOI: 10.1128/iai.71.7.3844-3851.2003] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Considerable morbidity and mortality result from schistosomiasis, an affliction affecting an estimated 200 million people. Although schistosomicidal drugs and other control measures (including public hygiene and snail control) exist, the advent of an efficacious vaccine remains the most potentially powerful means for controlling this disease. We have targeted a vaccine candidate (large subunit of calpain, Sm-p80) because of its consistent immunogenicity, protective potential, and integral role in surface membrane biogenesis of schistosomes. Since surface membrane renewal appears to be one of the major phenomena employed by schistosomes to evade the host's immune system; an immune response directed against Sm-p80 should render the parasite susceptible to immune clearance from the host by both providing a focus of attack and by potentially impairing the membrane repair process. In the present study, we have employed DNA immunization protocols using Sm-p80 with plasmids encoding granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). Sm-p80 by itself provided 39% protection (P = < or =0.0001) against challenge infection in C57BL/6 mice. This protection was increased to 44% (P = < or =0.0001) when the plasmid encoding GM-CSF was coadministered with Sm-p80 DNA. Coinjection of plasmid DNA encoding IL-4 with Sm-p80 DNA yielded a protection level of 42% (P = < or =0.0001). Statistically, the protection conferred by including GM-CSF, but not IL-4, was significantly greater than that when only Sm-p80 was used. Sm-p80 DNA by itself elicited strong responses that include IgG2A and IgG2B antibody isotypes. The introduction of GM-CSF DNA with Sm-p80 DNA led to distinct increases in total IgG and IgG1 titers, whereas the coadministration of IL-4 DNA with Sm-p80 DNA resulted in a slight elevation of IgG1 and IgG3 titers and in some reduction of IgG2A and IgG2B titers. Our data again indicate that Sm-p80 can be an excellent candidate for a schistosomiasis vaccine.
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Affiliation(s)
- Afzal A Siddiqui
- Department of Internal Medicine, Texas Tech University Health Sciences Center and Veterans Affairs Health Care System, Amarillo, Texas 79106, USA.
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50
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Siddiqui AA, Phillips T, Charest H, Podesta RB, Quinlin ML, Pinkston JR, Lloyd JD, Pompa J, Villalovos RM, Paz M. Enhancement of Sm-p80 (large subunit of calpain) induced protective immunity against Schistosoma mansoni through co-delivery of interleukin-2 and interleukin-12 in a DNA vaccine formulation. Vaccine 2003; 21:2882-9. [PMID: 12798631 DOI: 10.1016/s0264-410x(03)00159-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Schistosomiasis afflicts an estimated 200 million people in 76 countries and an additional 600 million people are at risk of acquiring this infection. Even though effective anthelmintic treatment and snail eradication control programs exist, the discovery of an effective vaccine still remains the most potentially powerful means of control for this disease. We have concentrated on a vaccine candidate (large subunit of calpain or Sm-p80) because of its potential in conferring protection against challenge infection and its pivotal role in surface membrane biogenesis of schistosomes. Since surface membrane renewal is a major phenomenon employed by hemohelminths to evade host immune system; an immune response directed against Sm-p80 should make the parasite prone to immune clearance from the host by both providing a well-targeted attack and by potentially inhibiting the surface membrane biogenesis process. In the present study, we have utilized DNA immunization protocols using Sm-p80 with plasmids encoding interleukin-2 (IL-2) and interleukin-12 (IL-12). Sm-p80 by itself provided a 39% protection (P</=0.0001) against challenge infection in C57BL/6 mice. This protection was increased to 57% (P</=0.0001) when plasmid encoding IL-2 was co-administered with Sm-p80 DNA. Co-injection of plasmid DNA encoding IL-12 with Sm-p80 DNA yielded a protection level of 45% (P</=0.0001). Statistically, the protection conferred by including IL-2 and IL-12 was significantly greater than when only the Sm-p80 was used. Sm-p80 DNA by itself elicited strong responses that includes IgG(2A) and IgG(2B) antibody isotypes. The introduction of IL-2 DNA with Sm-p80 DNA led to an increase in total IgG and IgG(2A) and IgG(2B) titres. Whereas co-administration of IL-12 DNA with Sm-p80 DNA resulted in the augmentation of only total IgG and IgG(2A). This data reinforces the potential of Sm-p80 as an excellent candidate for a schistosomiasis vaccine.
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Affiliation(s)
- Afzal A Siddiqui
- Department of Internal Medicine, Texas Tech Woman's Health & Research Institute, Texas Tech University Health Sciences Center, 1400 Wallace Blvd., Amarillo, Amarillo, TX 79106-1791, USA.
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