1
|
Tallima H, Mahmoud SS. Mechanisms of Arachidonic Acid In Vitro Schistosomicidal Potential. ACS OMEGA 2024; 9:23316-23328. [PMID: 38854551 PMCID: PMC11154912 DOI: 10.1021/acsomega.3c09906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/23/2024] [Accepted: 03/28/2024] [Indexed: 06/11/2024]
Abstract
Arachidonic acid (ARA) was shown to possess safe and effective schistosomicidal impact on larval and adult Schistosoma mansoni and Schistosoma hematobium in vitro and in vivo in laboratory rodents and in children residing in low and high endemicity regions. We herein examine mechanisms underlying ARA schistosomicidal potential over two experiments, using in each pool a minimum of 50 adult male, female, or mixed-sex freshly recovered, ex vivo S. mansoni. Worms incubated in fetal calf serum-free medium were exposed to 0 or 10 mM ARA for 1 h at 37 °C and immediately processed for preparation of surface membrane and whole worm body homogenate extracts. Mixed-sex worms were additionally used for evaluating the impact of ARA exposure on the visualization of outer membrane cholesterol, sphingomyelin (SM), and ceramide in immunofluorescence assays. Following assessment of protein content, extracts of intact and ARA-treated worms were examined and compared for SM content, neutral sphingomyelinase activity, reactive oxygen species levels, and caspase 3/7 activity. Arachidonic acid principally led to perturbation of the organization, integrity, and SM content of the outer membrane of male and female worms and additionally impacted female parasites via stimulating neutral sphingomyelinase activity and oxidative stress. Arachidonic powerful action on female worms combined with its previously documented ovocidal activities supports its use as safe and effective therapy against schistosomiasis, provided implementation of the sorely needed and long waited-for chemical synthesis.
Collapse
Affiliation(s)
- Hatem Tallima
- Department
of Chemistry, School of Sciences and Engineering, American University in Cairo, New Cairo, Cairo 11835, Egypt
| | - Soheir S. Mahmoud
- Department
of Parasitology, Theodore Bilharz Research
Institute, Warrak El-Hadar, Imbaba,Giza 12411, Egypt
| |
Collapse
|
2
|
Maharjan S, Kirk RS, Lawton SP, Walker AJ. Human growth factor-mediated signalling through lipid rafts regulates stem cell proliferation, development and survival of Schistosoma mansoni. Open Biol 2024; 14:230262. [PMID: 38195062 PMCID: PMC10776228 DOI: 10.1098/rsob.230262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 11/16/2023] [Indexed: 01/11/2024] Open
Abstract
Although the mechanisms by which schistosomes grow and develop in humans are poorly defined, their unique outer tegument layer, which interfaces with host blood, is considered vital to homeostasis of the parasite. Here, we investigated the importance of tegument lipid rafts to the biology of Schistosoma mansoni in the context of host-parasite interactions. We demonstrate the temporal clustering of lipid rafts in response to human epidermal growth factor (EGF) during early somule development, concomitant with the localization of anteriorly orientated EGF receptors (EGFRs) and insulin receptors, mapped using fluorescent EGF/insulin ligand. Methyl-β-cyclodextrin (MβCD)-mediated depletion of cholesterol from lipid rafts abrogated the EGFR/IR binding at the parasite surface and led to modulation of protein kinase C, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase and Akt signalling pathways within the parasite. Furthermore, MβCD-mediated lipid raft disruption, and blockade of EGFRs using canertinib, profoundly reduced somule motility and survival, and attenuated stem cell proliferation and somule growth and development particularly to the fast-growing liver stage. These findings provide a novel paradigm for schistosome development and vitality in the host, driven through host-parasite interactions at the tegument, that might be exploitable for developing innovative therapeutic approaches to combat human schistosomiasis.
Collapse
Affiliation(s)
- Shradha Maharjan
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
| | - Ruth S. Kirk
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
| | - Scott P. Lawton
- Centre for Epidemiology and Planetary Health, SRUC School of Veterinary Medicine, Scotland's Rural College, West Mains Road, Edinburgh EH9 3JG, UK
| | - Anthony J. Walker
- Molecular Parasitology Laboratory, School of Life Sciences, Pharmacy and Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
| |
Collapse
|
3
|
Tallima H, Hanna VS, El Ridi R. Arachidonic Acid Is a Safe and Efficacious Schistosomicide, and an Endoschistosomicide in Natural and Experimental Infections, and Cysteine Peptidase Vaccinated Hosts. Front Immunol 2020; 11:609994. [PMID: 33281832 PMCID: PMC7705376 DOI: 10.3389/fimmu.2020.609994] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 10/26/2020] [Indexed: 12/11/2022] Open
Abstract
Blood flukes of the genus Schistosoma are covered by a protective heptalaminated, double lipid bilayer surface membrane. Large amounts of sphingomyelin (SM) in the outer leaflet form with surrounding water molecules a tight hydrogen bond barrier, which allows entry of nutrients and prevents access of host immune effectors. Excessive hydrolysis of SM to phosphoryl choline and ceramide via activation of the parasite tegument-associated neutral sphingomyelinase (nSMase) with the polyunsaturated fatty acid, arachidonic acid (ARA) leads to parasite death, via allowing exposure of apical membrane antigens to antibody-dependent cell-mediated cytotoxicity (ADCC), and accumulation of the pro-apoptotic ceramide. Surface membrane nSMase represents, thus, a worm Achilles heel, and ARA a valid schistosomicide. Several experiments conducted in vitro using larval, juvenile, and adult Schistosoma mansoni and Schistosoma haematobium documented ARA schistosomicidal potential. Arachidonic acid schistosomicidal action was shown to be safe and efficacious in mice and hamsters infected with S. mansoni and S. haematobium, respectively, and in children with light S. mansoni infection. A combination of praziquantel and ARA led to outstanding cure rates in children with heavy S. mansoni infection. Additionally, ample evidence was obtained for the powerful ARA ovocidal potential in vivo and in vitro against S. mansoni and S. haematobium liver and intestine eggs. Studies documented ARA as an endogenous schistosomicide in the final mammalian and intermediate snail hosts, and in mice and hamsters, immunized with the cysteine peptidase-based vaccine. These findings together support our advocating the nutrient ARA as the safe and efficacious schistosomicide of the future.
Collapse
Affiliation(s)
- Hatem Tallima
- Zoology Department, Faculty of Science, Cairo University, Giza, Egypt.,Department of Chemistry, School of Science and Engineering, American University in Cairo, New Cairo, Cairo, Egypt
| | - Violette S Hanna
- Zoology Department, Faculty of Science, Cairo University, Giza, Egypt
| | - Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Giza, Egypt
| |
Collapse
|
4
|
El-Moslemany RM, Eissa MM, Ramadan AA, El-Khordagui LK, El-Azzouni MZ. Miltefosine lipid nanocapsules: Intersection of drug repurposing and nanotechnology for single dose oral treatment of pre-patent schistosomiasis mansoni. Acta Trop 2016; 159:142-8. [PMID: 27039667 DOI: 10.1016/j.actatropica.2016.03.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 03/30/2016] [Accepted: 03/31/2016] [Indexed: 10/22/2022]
Abstract
A dual drug repurposing/nanotechnological approach was used to develop an alternative oral treatment for schistosomiasis mansoni using miltefosine (MFS), an anticancer alkylphosphocholine, and lipid nanocapsules (LNCs) as oral nanovectors. We demonstrated earlier that MFS possesses significant activity against different developmental stages of Schistosoma mansoni in the mouse model using 5 successive 20mg/kg/day oral doses. Moreover, an effective single dose (20mg/kg) oral treatment against the adult stage of S. mansoni in mice was developed using LNCs, particularly modified with CTAB, a positive charge imparting agent (MFS-LNC-CTAB(+)), or oleic acid as membrane permeabilizer (MFS-LNC-OA). Efficacy enhancement involved, at least in part, targeting of the worm tegument with MFS-LNCs as a new therapeutic entity. As the tegument surface charge and composition may differ in pre-patent stages of the parasite, it was of importance in the present study to assess the efficacy of a single oral dose of the two MFS-LNC formulations against invasive and immature stages for potential advantage relative to praziquantel. Results indicated potent schistosomicidal effects against both invasive and immature stages of S. mansoni in infected mice, efficacy being both formulation and developmental stage dependent. This was indicated by the significant reduction in the total worm burden of the invasive stage by 91.6% and 76.8% and the immature stage by 82.7% and 96.7% for MFS-LNC-CTAB+ and MFS-LNC-OA, respectively. Histopathological findings indicated amelioration of hepatic pathology with regression of the granulomatous inflammatory reaction and reduction in granulomas number and size, verifying marked improvement in architecture of hepatic lobules. From a clinical perspective, MFS-LNCs offer potential as an alternative single oral dose nanomedicine with a wide therapeutic profile for the mass chemotherapy of schistosomiasis mansoni.
Collapse
|
5
|
El Ridi R, Tallima H, Migliardo F. Biochemical and biophysical methodologies open the road for effective schistosomiasis therapy and vaccination. Biochim Biophys Acta Gen Subj 2016; 1861:3613-3620. [PMID: 27062905 DOI: 10.1016/j.bbagen.2016.03.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2016] [Revised: 03/19/2016] [Accepted: 03/22/2016] [Indexed: 12/27/2022]
Abstract
BACKGROUND Schistosomiasis caused by blood-dwelling flukes, namely Schistosoma mansoni and Schistosoma haematobium is a severe debilitating disease, widespread in sub-Saharan Africa, the Middle East, and South America. Developing and adult worms are unscathed by the surrounding immune effectors and antibodies because the parasite is protected by a double lipid bilayer armor which allows access of nutrients, while binding of specific antibodies is denied. SCOPE OF REVIEW Fluorescence recovery after bleaching, extraction of surface membrane cholesterol by methyl-β-cyclodextrin, inhibition and activation of sphingomyelin biosynthesis and hydrolysis, and elastic incoherent and quasi-elastic neutron scattering approaches have helped to clarify the basic mechanism of this immune evasion, and showed that sphingomyelin (SM) molecules in the worm apical lipid bilayer form with surrounding water molecules a tight hydrogen bond barrier. Viability of the parasite and permeability of the outer shield are controlled by equilibrium between SM biosynthesis and activity of a tegument-associated neutral sphingomyelinase (nSMase). MAJOR CONCLUSIONS Excessive nSMase activation by polyunsaturated fatty acids (PUFA), such as arachidonic acid (ARA) leads to disruption of the SM molecules and associated hydrogen bond network, with subsequent access of host antibodies and immune effectors to the outer membrane and eventual parasite death. GENERAL SIGNIFICANCE ARA was predicted and shown to be a potent schistosomicide in vitro and in vivo in experimental animals and in children. Additionally, it was advocated that schistosomiasis vaccine candidates should be selected uniquely among excretory-secretory products of developing worms, as contrary to cytosolic and surface membrane antigens, they are able to activate the effector functions of the host antibodies and toxic molecules. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo".
Collapse
Affiliation(s)
- Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt.
| | - Hatem Tallima
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt; Department of Chemistry, School of Science and Engineering, American University in Cairo, New Cairo, 11835 Cairo, Egypt
| | - Federica Migliardo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98166 Messina, Italy
| |
Collapse
|
6
|
Migliardo F, Tallima H, El Ridi R. Is there a sphingomyelin-based hydrogen bond barrier at the mammalian host-schistosome parasite interface? Cell Biochem Biophys 2014; 68:359-67. [PMID: 23943053 DOI: 10.1007/s12013-013-9716-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Schistosomes develop, mature, copulate, lay eggs, and live for years in the mammalian host bloodstream, importing nutrients across the tegument, but entirely impervious to the surrounding elements of the immune system. We have hypothesized that sphingomyelin (SM) in the parasite apical lipid bilayer is responsible for these sieving properties via formation of a tight hydrogen bond network with the surrounding water. Here we have used quasi-elastic neutron scattering for characterizing the diffusion of larval and adult Schistosoma mansoni and adult Schistosoma haematobium in the surrounding medium, under various environmental conditions. The results documented the presence of a hydrogen bond barrier around larvae and adult schistosomes. The hydrogen bond network readily collapses if worms are subjected to hypoxic conditions, likely via activation of the parasite tegument-associated neutral sphingomyelinase, and consequent excessive SM hydrolysis. The slower dynamics of lung-stage larvae as compared to adult worms has been related to the existence of hydrogen-bonded networks of different strength and then to their differential resistance to immune attacks.
Collapse
Affiliation(s)
- Federica Migliardo
- Department of Physics and Earth Sciences, University of Messina, Messina, 98166, Italy,
| | | | | |
Collapse
|
7
|
Ghosh D, Misra KK. Comparison of fatty acid contents of the neutral and phospholipids of the trematode Paramphistomum cervi and liver of its host, Capra hircus. J Parasit Dis 2014; 38:223-32. [PMID: 24808657 DOI: 10.1007/s12639-012-0229-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 12/21/2012] [Indexed: 10/27/2022] Open
Abstract
The present observation records the lipid classes and their fatty acid composition of the neutral lipid and phospholipid of the trematode Paramphistomum cervi and liver of its host Capra hircus, the common Indian goat. Thin Layer Chromatography and Gas Liquid Chromatography were used to identify different neutral lipid and phospholipid components. The results show that among the neutral lipid fractions, the amount of combined hydrocarbon, wax ester and steryl ester is more or less equal in parasite and its host, but the percent of triacylglycerol is more in host liver than the parasite and the percent of total sterol is more in parasite than that of its host liver. Among the phospholipid fractions, phosphatidylinositol and phosphatidylethanolamine in the trematode parasite P. cervi and phosphatidylcholine and cardiolipin in the host's liver are the major components. The predominant fatty acids in the neutral lipid and phospholipid fractions of both the host liver and the trematode P. cervi include C16:0, C18:0, C18:1, and C18:2. The results reveal that the parasite P. cervi take up almost all the lipid and fatty acids from their host, which is required for their life cycle.
Collapse
Affiliation(s)
- Debasree Ghosh
- Department of Zoology, R.B.C. College, Naihati, 743 165 West Bengal India
| | - K K Misra
- Department of Zoology, R.B.C. College, Naihati, 743 165 West Bengal India
| |
Collapse
|
8
|
El Ridi RAF, Tallima HAM. Novel therapeutic and prevention approaches for schistosomiasis: review. J Adv Res 2012; 4:467-78. [PMID: 25685454 PMCID: PMC4293887 DOI: 10.1016/j.jare.2012.05.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Revised: 05/12/2012] [Accepted: 05/15/2012] [Indexed: 01/23/2023] Open
Abstract
Schistosomiasis is a debilitating disease affecting approximately 600 million people in 74 developing countries, with 800 million, mostly children at risk. To circumvent the threat of having praziquantel (PZQ) as the only drug used for treatment, several PZQ derivatives were synthesized, and drugs destined for other parasites were used with success. A plethora of plant-derived oils and extracts were found to effectively kill juvenile and adult schistosomes, yet none was progressed to pre- and clinical studies except an oleo-gum resin extracted from the stem of Commiphora molmol, myrrh, which action was challenged in several trials. We have proposed an essential fatty acid, a component of our diet and cells, the polyunsaturated fatty acid arachidonic acid (ARA) as a remedy for schistosomiasis, due to its ability to activate the parasite tegument-bound neutral sphingomyelinase, with subsequent hydrolysis of the apical lipid bilayer sphingomyelin molecules, allowing access of specific antibody molecules, and eventual worm attrition. This concept was convincingly supported using larval and adult Schistosoma mansoni and Schistosoma haematobium worms in in vitro experiments, and in vivo studies in inbred mice and outbred hamsters. Even if ARA proves to be an entirely effective and safe therapy for schistosomiasis, it will not prevent reinfection, and accordingly, the need for developing an effective vaccine remains an urgent priority. Our studies have supported the status of S. mansoni calpain, glutathione-S-transferase, aldolase, triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, enolase, and 2-cys peroxiredoxin as vaccine candidates, as they are larval excreted-secreted products and, contrary to the surface membrane molecules, are entirely accessible to the host immune system effector elements. We have proposed that the use of these molecules, in conjunction with Th2 cytokines-inducing adjuvants for recruiting and activating eosinophils and basophils, will likely lead to development and implementation of a sterilizing vaccine in a near future.
Collapse
Affiliation(s)
- Rashika A F El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt
| | - Hatem A-M Tallima
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt
| |
Collapse
|
9
|
Changes in the small intestine ofSchistosoma mansoni-infected mice fed a high-fat diet. Parasitology 2012; 139:716-25. [DOI: 10.1017/s0031182011002307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARYThe consumption of a high-fat diet modifies both the morphology of the small intestine and experimentally tested effects of schistosomiasis mansoni. However, whether a schistosomiasis infection associated with a high-fat diet causes injury to the small intestine has never been investigated. Mice were fed either a high-fat or a standard-fat diet for 6 months and were then infected withSchistosoma mansonicercariae. Physical characteristics of the intestinal tissue (mucosal thickness, small intestinal villi length and height, and abundance of goblet cells and enterocytes on the villous surface) and the distribution of granulomas along the intestinal segments and their developmental stage were measured at the time of sacrifice (9 or 17 weeks post-infection). The group fed a high-fat diet exhibited different granuloma stages, whereas the control group possessed only exudative granulomas. The chronically infected mice fed a high-fat diet exhibited higher granuloma and egg numbers than the acutely infected group. Exudative, exudative/exudative-productive and exudative-productive granulomas were present irrespective of diet. Computer-aided morphometric analysis confirmed that villus length, villus width, muscular height and submucosal height of the duodenal and jejunal segments were affected by diet and infection. In conclusion, a high-fat diet and infection had a significant impact on the small intestine morphology and morphometry among the animals tested.
Collapse
|
10
|
Corrêa CL, Lisboa PC, Oliveira ED, Moura EGD, Oliveira RMFD, Gomes AC, Machado-Silva JR. The outcome of acute schistosomiasis infection in adult mice with postnatal exposure to maternal malnutrition. Mem Inst Oswaldo Cruz 2011; 106:584-93. [DOI: 10.1590/s0074-02762011000500011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Accepted: 05/24/2011] [Indexed: 11/22/2022] Open
|
11
|
Enzymatic activity and immunolocalization of Schistosoma mansoni and Schistosoma haematobium neutral sphingomyelinase. Mol Biochem Parasitol 2011; 178:23-8. [PMID: 21524668 DOI: 10.1016/j.molbiopara.2011.04.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Revised: 04/04/2011] [Accepted: 04/06/2011] [Indexed: 11/22/2022]
Abstract
We predicted, and provided evidence for, the existence of a schistosome tegument-associated Mg(2+)-dependent neutral sphingomyelinase (nSMase), which controls hydrolysis of surface membrane sphingomyelin molecules, thus allowing nutrients, but not host antibodies, to access proteins at the host-parasite interface. While a putative nSMase was identified in a recent Schistosoma mansoni genome sequencing and analysis study, our report is the first to measure nSMase enzymatic activity in Triton X-100-solubilized surface membrane (Sup 1) and whole worm soluble (SWAP) molecules of male and female S. mansoni and Schistosoma haematobium. Neutral, but no acidic, sphingomyelinase activity was readily detectable by the amplex red sphingomyelinase assay, and increased with incubation time and protein amount. Like nSMase family members, the schistosome nSMase activity was significantly (P<0.05 to <0.0001) enhanced by unsaturated fatty acids and phosphatidyl serine and significantly (P<0.01) decreased following exposure to the nSMase specific inhibitor GW4869. Peptides based on the published sequence of S. mansoni putative nSMase and used in a multiple antigen peptide form induced the generation of specific antibodies, which readily bound to the immunogen and to the cognate protein in Sup 1 and SWAP. Immunofluorescence studies suggested the parasite nSMase is located in the worm tegument and gut lining. Studies using RNA interference are in progress to define nSMase role in larval and adult worm surface membrane antigen exposure and unsaturated fatty acid-mediated attrition.
Collapse
|
12
|
Alencar ACMDB, Neves RH, Águila MB, Mandarim-de-Lacerda CA, Gomes DC, Machado-Silva JR. High fat diet has a prominent effect upon the course of chronic schistosomiasis mansoni in mice. Mem Inst Oswaldo Cruz 2009; 104:608-13. [DOI: 10.1590/s0074-02762009000400013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2008] [Accepted: 03/04/2009] [Indexed: 11/22/2022] Open
|
13
|
El Ridi R, Tallima H. Schistosoma mansoni ex vivo lung-stage larvae excretory-secretory antigens as vaccine candidates against schistosomiasis. Vaccine 2008; 27:666-73. [PMID: 19056448 DOI: 10.1016/j.vaccine.2008.11.039] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2008] [Revised: 11/09/2008] [Accepted: 11/12/2008] [Indexed: 10/21/2022]
Abstract
Schistosoma mansoni lung-stage larvae are known to be the major target of innate and acquired immunity to schistosomiasis. Lung schistosomula cytosolic or surface membrane antigens are hidden, entirely inaccessible to the host immune system, and hence are not particularly important as vaccine candidates. Conversely, excretory-secretory (E-S) products released from intact, viable, elongated, and contractile schistosomula are ideal potential vaccines, as such molecules can readily play a central role in the induction of local primary and memory immune response effectors that would directly target, surround, and pursue the larvae while negotiating the lung capillaries. Therefore, 6-day-old ex vivo larvae were isolated from mouse or hamster lung cells and used for generation of E-S products, which were shown to elicit strong immune responses and significant (P<0.05) protection against challenge infection in BALB/c mice. Proteomic analysis of E-S molecules following 10x concentration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis identified peptides related to innumerable host and about 15 S. mansoni-specific proteins. Selected S. mansoni-specific E-S peptides prepared in a multiple antigen peptide (MAP) or recombinant form were shown to stimulate considerable specific antibody response and peripheral blood mononuclear cell expression of mRNA for several cytokines in immunized C57BL/6 and BALB/c mice. However, highly significant (P<0.05 to <0.005) reduction in challenge infection worm burden and egg load was recorded only when the immunization conditions in test mice provided the S. mansoni antigen-specific T helper (Th) type response milieu favorable for each immunogen. That was polarized Th1 for S. mansoni aldolase and thioredoxin peroxidase 1 MAPs, polarized Th2 for recombinant 14-3-3-like protein, mixed Th1/Th17 for calpain MAP, and mixed Th1/Th2 for recombinant p18 protein. The findings together indicated that the immune responses issue is as critical as the nature and source of the antigen for the development of vaccine against schistosomiasis.
Collapse
Affiliation(s)
- Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt.
| | | |
Collapse
|
14
|
Tallima H, El Ridi R. Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase is a lung-stage schistosomula surface membrane antigen. Folia Parasitol (Praha) 2008; 55:180-6. [DOI: 10.14411/fp.2008.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
15
|
Transferrin uptake in Trypanosoma cruzi is impaired by interference on cytostome-associated cytoskeleton elements and stability of membrane cholesterol, but not by obstruction of clathrin-dependent endocytosis. Exp Parasitol 2008; 119:58-66. [DOI: 10.1016/j.exppara.2007.12.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Revised: 10/22/2007] [Accepted: 12/20/2007] [Indexed: 11/23/2022]
|
16
|
Light and confocal microscopic observations of adult Schistosoma mansoni from mice fed on a high-fat diet. J Helminthol 2007; 81:361-8. [PMID: 17956644 DOI: 10.1017/s0022149x07799121] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The morphological aspects of Schistosoma mansoni adult worms recovered from albino mice fed on a cholesterol-rich diet compared to mice fed on a standard chow were investigated. After feeding on their respective diets for over a period of 5 months, mice were subcutaneously infected with c. 50 S. mansoni cercariae/mouse. Blood samples were obtained 1 day prior to experimental infections and 63 days later, when mice were euthanized by jugular section (hypovolaemic shock). Total cholesterol (TC) levels were determined. Recovered worms were stained with hydrochloric carmine, and preserved as whole-mounts for examination by bright-field and laser confocal microscopy. The infected mice fed on high-fat chow showed higher levels of serum lipoproteins than the infected mice fed on standard chow, except for very-low-density lipoprotein cholesterol (VLDL-c) and triglycerides (TG). In this experiment, worms from mice fed on a high-fat chow showed a greater percentage of morphological differentiation regarding supernumerary testes, seminal vesicle, and seminal receptacle. In mice of this group, the rate of oocyte laying in the ovary was much higher than in control females. The present results suggest that cholesterol could be actively involved in the modulation of cell signalling and reproduction, because the lobes contained fully developed oocytes in variable amounts, different from control males. The data presented here are the first to report the role of a cholesterol-rich diet affecting the development of S. mansoni worms.
Collapse
|
17
|
Tallima H, Hamada M, El Ridi R. Evaluation of cholesterol content and impact on antigen exposure in the outer lipid bilayer of adult schistosomes. Parasitology 2007; 134:1775-83. [PMID: 17617933 DOI: 10.1017/s0031182007003174] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SUMMARYDeveloping and adultSchistosoma mansoniandS. haematobiumintact worms do not bind specific antibodies, likely because of structural and biochemical modifications of the outer lipid bilayer. We have estimated the amount of cholesterol in the apical membrane of adult schistosomes via extraction with the membrane-impermeable, cholesterol-binding drug, methyl-β-cyclodextrin (MBCD), followed by filipin staining of the worms, and evaluation of the amount of cholesterol released in the medium by a commercially available, enzymatic colorimetric assay. Positive correlations between amount of released cholesterol, MBCD concentration, and worm number and age provided evidence for the sensitivity and validity of the newly developed method. Treatment with 40 mmMBCD for 2 h at 37°C led to total loss of cholesterol from the worm outer membrane, as assessed by filipin staining, and the released cholesterol values were used to estimate the amount of cholesterol per worm and per an approximate surface area unit. Additionally, total depletion of outer membrane cholesterol was associated with exposure of surface membrane antigens to specific antibody binding in 50% and 70% ofS. haematobiumandS. mansoniworms, respectively. These findings together suggest that cholesterol is an essential, but not the sole, factor in sequestration of surface membrane antigens in schistosomes.
Collapse
Affiliation(s)
- H Tallima
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt
| | | | | |
Collapse
|
18
|
Kusel JR, Al-Adhami BH, Doenhoff MJ. The schistosome in the mammalian host: understanding the mechanisms of adaptation. Parasitology 2007; 134:1477-526. [PMID: 17572930 DOI: 10.1017/s0031182007002971] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
SUMMARYIn this review, we envisage the host environment, not as a hostile one, since the schistosome thrives there, but as one in which the relationship between the two organisms consists of constant communication, through signalling mechanisms involving sense organs, surface glycocalyx, surface membrane and internal organs of the parasite, with host fluids and cells. The surface and secretions of the schistosome egg have very different properties from those of other parasite stages, but adapted for the dispersal of the eggs and for the preservation of host liver function. We draw from studies of mammalian cells and other organisms to indicate how further work might be carried out on the signalling function of the surface glycocalyx, the raft structure of the surface and existence of pores in the surface membrane, the repair of the surface membrane, the role of the membrane structure in ion channel function (including recent work on the actin cytoskeleton and calcium channels) and the possible role of P-glycoproteins in the adaptation of the parasite to its environment. We are speculative in some areas, such as the suggestions that variability in surface properties of schistosomes may relate to the existence of membrane rafts and that parasite communities may exhibit quorum sensing. This speculative approach is adopted with the hope that future work on the whole organisms and their interactions will be encouraged.
Collapse
Affiliation(s)
- J R Kusel
- Glasgow Biomedical Research Centre, University of Glasgow, Glasgow G12 8TA, UK.
| | | | | |
Collapse
|
19
|
Gobert GN, Chai M, McManus DP. Biology of the schistosome lung-stage schistosomulum. Parasitology 2007; 134:453-60. [PMID: 17109780 PMCID: PMC2754249 DOI: 10.1017/s0031182006001648] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 09/08/2006] [Accepted: 09/11/2006] [Indexed: 11/07/2022]
Abstract
Past and more recent research has examined the ultrastructure, metabolism, cell biology, genomics and post-genomics of schistosome schistosomula. These areas are considered and discussed in this review with particular emphasis on (1) the early migration phases through the host, (2) interaction of the host immune response with the parasite surface, (3) glucose uptake mechanisms, and (4) defining the transcriptional profiles of lung-stage schistosomula compared with other developmental stages using microarrays. The microarray profiling studies suggest caution is required when considering the use of schistosomes obtained by in vitro means for molecular or biochemical studies.
Collapse
Affiliation(s)
- G N Gobert
- Molecular Parasitology Laboratory, Infectious Diseases and Immunology Division, The Queensland Institute of Medical Research, 300 Herston Road, Brisbane, Queensland 4006 Australia.
| | | | | |
Collapse
|
20
|
Neves RH, Miranda de Barros Alencar AC, Costa-Silva M, Aguila MB, Mandarim-de-Lacerda CA, Machado-Silva JR, Gomes DC. Long-term feeding a high-fat diet causes histological and parasitological effects on murine schistosomiasis mansoni outcome. Exp Parasitol 2006; 115:324-32. [PMID: 17112519 DOI: 10.1016/j.exppara.2006.09.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2006] [Revised: 08/30/2006] [Accepted: 09/08/2006] [Indexed: 11/15/2022]
Abstract
This study investigated whether long-term feeding a high-fat diet (HFC) has an effect on schistosomiasis mansoni outcome compared to standard chow diet (SC). Swiss Webster female mice (3 wk old) fed each diet over 5 months, and then were infected with 50 Schistosoma mansoni cercariae. Their nutritional status was assessed by monitoring growth rates twice a week and measuring serum levels of lipoproteins. Mice were euthanised 63 days after infection. Parasitological and liver histological analyses were performed. The levels of TC, HDL-C and LDL-C, fecal and tissue schistosome eggs were statistically different (p<0.05) between groups. Livers from HFC mice showed exudative, exudative/exudative-productive, exudative-productive and productive granulomas, some degree of hepatic steatosis and focal necrosis. Mice fed normal-chow did not present productive granulomas and hepatic steatosis. The morphometric evaluation of hepatic granulomas did not reach statistical significance (p>0.05) between diets assayed. The high-fat diet for long-term produces effects on schistosomiasis mansoni outcome.
Collapse
Affiliation(s)
- Renata Heisler Neves
- Laboratory of Helminthology Romero Lascasas Porto, Biomedical Center, Department of Pathology and Laboratories, Faculty of Medical Sciences, State University of Rio de Janeiro, Brazil
| | | | | | | | | | | | | |
Collapse
|
21
|
El Ridi R, Tallima H. Equilibrium in lung schistosomula sphingomyelin breakdown and biosynthesis allows very small molecules, but not antibody, to access proteins at the host-parasite interface. J Parasitol 2006; 92:730-7. [PMID: 16995389 DOI: 10.1645/ge-745r1.1] [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] [Indexed: 11/10/2022] Open
Abstract
The mechanism by which lung-stage schistosomula expose proteins at the host-parasite interface to nutrient, but not antibody, uptake has been obscure. We have found that Schistosoma mansoni and Schistosoma haematobium larvae emerging from host lung at a pH of around 7.5, and fixed with diluted formaldehyde (HCHO), readily bind specific antibodies in indirect membrane immunofluorescence. Data on inhibitors and activators of parasite tegument-bound, magnesium-dependent, neutral sphingomyelinase (nSMase), and sphingomyelin biosynthesis inhibitors revealed that equilibrium in schistosomular sphingomyelin breakdown and biosynthesis prevents antibody binding, yet permits access of small HO-CH2-OH polymers to interact with and cross-link proteins at the host-parasite interface, allowing for their serological visualization.
Collapse
Affiliation(s)
- Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt.
| | | |
Collapse
|
22
|
El Ridi R, Salem R, Wagih A, Mahana N, El Demellawy M, Tallima H. Influence of interleukin-2 and interferon-gamma in murine schistosomiasis. Cytokine 2006; 33:281-8. [PMID: 16564704 DOI: 10.1016/j.cyto.2006.01.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2005] [Revised: 10/16/2005] [Accepted: 01/18/2006] [Indexed: 10/24/2022]
Abstract
Schistosoma mansoni-infected mice were administered at the time of parasite residency in the lung with recombinant murine interleukin (IL)-2 or interferon-gamma (IFN-gamma), to evaluate the impact of cytokines in host responses to primary schistosomiasis. S. mansoni lung-stage schistosomula did not affect plasma lipids levels in BALB/c, while elicited significant (p<0.05) increase in free fatty acids (FA) and decrease in cholesterol plasma levels in C57BL/6 and CD1 mice, and stimulated expression of mRNA for Th2 cytokines in BALB/c and Th1 cytokines in C57BL/6 and CD1 mice. Production of specific antibodies was negligible in the 3 strains. Interleukin-2 treatment elicited significant (p<0.001) decrease in triglycerides (TG) in CD1, and decrease in TG and cholesterol plasma levels and down-regulation of TNF-alpha mRNA expression in C57BL/6 mice. Induction of type 2 cytokines and/or IFN-gamma mRNA expression did not lead to increase in percentage of specific antibody responders in any mouse strain. Exogenous IL-2-related reduction in cholesterol plasma levels and TNF-alpha mRNA expression in C57BL/6 mice was associated with significant (p<0.05) decrease in adult worm recovery and egg count. Treatment with IFN-gamma elicited significant (p<0.05) free FA plasma levels increase in BALB/c and C57BL/6 and decrease in CD1 mice. Expression of type 2 cytokines mRNA was stimulated in BALB/c and CD1 mice, yet was not accompanied with increase in humoral responses. Exogenous IFN-gamma-related reduction in free FA plasma levels and IFN-gamma mRNA response, and up-regulation of TNF-alpha mRNA expression in CD1 mice were associated with significant increase in adult worm burden and egg load. The data were discussed in an attempt to define host factors predictive of resistance to schistosome infection.
Collapse
Affiliation(s)
- Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt.
| | | | | | | | | | | |
Collapse
|
23
|
El Ridi R, Wagih A, Salem R, Mahana N, El Demellawy M, Tallima H. Impact of interleukin-1 and interleukin-6 in murine primary schistosomiasis. Int Immunopharmacol 2006; 6:1100-8. [PMID: 16714213 DOI: 10.1016/j.intimp.2006.01.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 01/19/2006] [Accepted: 01/27/2006] [Indexed: 10/25/2022]
Abstract
BACKGROUND Immunization with schistosome antigens invariably elicits a plethora of cytokines and, hence, it is reasonable to assume that these cytokines influence host responses to challenge lung-stage larvae and, consequently, the adult worm burden, and may be responsible for the erratic data generally observed in protection studies against schistosome infection. METHODS Schistosoma mansoni-infected mice were administered with recombinant interleukin (IL)-1beta or IL-6 to evaluate the impact of cytokines in host responses to lung-stage schistosomula, and subsequent effects on adult worm parameters. Plasma lipid levels were assayed by colorimetric enzymatic tests and antibody responses by ELISA. Cytokine profile in peripheral blood mononuclear cells was evaluated by RT-PCR. RESULTS S. mansoni infection elicited, at the time of parasite residency in the lung, significant increase in free fatty acids (FA) and decrease in cholesterol plasma levels in C57BL/6 and CD1 mice, and stimulation of mRNA expression for cytokines of T helper type (Th) 2 in BALB/c, Th1 in C57BL/6, and Th1/Th2 in CD1 mice. However, no specific antibody production was evident in any mouse strain. In BALB/c mice, exogenous IL-1beta-related plasma free FA level significant increase, stimulation of expression of IL-1 and IL-12 mRNA, and considerable increase in percent of specific antibody-producing mice were associated with significant reduction in adult worm burden and egg load. In contrast, exogenous IL-1beta elicited decrease in free FA plasma levels, and down-regulation of cytokines' mRNA expression in C57BL/6 and CD1 mice, changes associated with aggravation of the worm burden. Likewise, exogenous IL-6 failed to stimulate increase in plasma free FA levels or percent of antibody-producing mice except in BALB/c mice, effects that were protective for the host in BALB/c and for the parasite in C57BL/6 and CD1 mice. CONCLUSION These findings were discussed in relation to the erratic data of protection experiments with schistosome subunit antigens in different mouse strains.
Collapse
Affiliation(s)
- Rashika El Ridi
- Zoology Department, Faculty of Science, Cairo University, Cairo 12613, Egypt.
| | | | | | | | | | | |
Collapse
|
24
|
Tallima H, Salah M, El-Ridi R. In vitro and in vivo effects of unsaturated fatty acids on Schistosoma mansoni and S. haematobium lung-stage larvae. J Parasitol 2006; 91:1094-102. [PMID: 16419753 DOI: 10.1645/ge-514r.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Incubation of Schistosoma mansoni lung-stage larvae in 90% corn oil for 6 hr was shown to elicit exposure of their, otherwise masked, apical membrane antigens to binding of anti-schistosome antibodies in the indirect membrane immunofluorescence test (IF). The possibility that unsaturated fatty acids (FA) are responsible for this effect was herein supported by IF data on ex vivo lung-stage larvae of S. mansoni and S. haematobium incubated for 1/2-2 hr with 80% corn oil, 50% olive oil, or 10-20 microM arachidonic acid. Treatment with unsaturated FA followed by filipin staining for cholesterol visualization indicated that unsaturated FA do not induce exposure of schistosomular surface membrane antigens via extraction of surface membrane cholesterol. Evidence using inhibitors and stimulators of neutral sphingomyelinase suggested that unsaturated FA perhaps activate worm tegument-bound neutral sphingomyelinase, leading to sphingomyelin hydrolysis and changes in surface membrane fluidity. Larval apical membrane antigens are, thus, allowed to diffuse freely in the plane of the membrane and bind specific antibodies in IE Excessive sphingomyelin hydrolysis might explain why high FA concentrations or long incubation periods eventually lead to larval death. The significant decrease (P < 0.01) in S. mansoni and increase (P < 0.02) in S. haematobium worm recovery in BALB/c mice given unsaturated FA-high and -poor diets, respectively, indicated these findings have in vivo relevance and led to the proposal that unsaturated FA likely plays a role in natural attrition of S. mansoni and S. haematobium lung-stage larvae.
Collapse
Affiliation(s)
- Hatem Tallima
- Zoology Department, Faculty of Science, Cairo University, Egypt
| | | | | |
Collapse
|