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Parasites & Vectors Dec 2023Schistosomiasis, the second largest parasitic disease in the world after malaria, poses a significant threat to human health and causes public health issues. The disease... (Review)
Review
Exploring the immune interactions between Oncomelania hupensis and Schistosoma japonicum, with a cross-comparison of immunological research progress in other intermediate host snails.
Schistosomiasis, the second largest parasitic disease in the world after malaria, poses a significant threat to human health and causes public health issues. The disease primarily affects populations in economically underdeveloped tropical regions, earning it the title of "neglected tropical disease". Schistosomiasis is difficult to eradicate globally if medication alone is used. One of the essential elements of thorough schistosomiasis prevention and control is the management and disruption of the life cycle of intermediate host snails. The key approach to controlling the transmission of schistosomiasis is to control the intermediate hosts of the schistosome to disrupt its life cycle. We believe that approaching it from the perspective of the intermediate host's immunity could be an environmentally friendly and potentially effective method. Currently, globally significant intermediate host snails for schistosomes include Oncomelania hupensis, Biomphalaria glabrata, and Bulinus truncatus. The immune interaction research between B. glabrata and Schistosoma mansoni has a history of several decades, and the complete genome sequencing of both B. glabrata and B. truncatus has been accomplished. We have summarized the immune-related factors and research progress primarily studied in B. glabrata and B. truncatus and compared them with several humoral immune factors that O. hupensis research focuses on: macrophage migration inhibitory factor (MIF), Toll-like receptors (TLRs), and thioredoxin (Trx). We believe that continued exploration of the immune interactions between O. hupensis and Schistosoma japonicum is valuable. This comparative analysis can provide some direction and clues for further in-depth research. Comparative immunological studies between them not only expand our understanding of the immune defense responses of snails that act as intermediaries for schistosomes but also facilitate the development of more comprehensive and integrated strategies for schistosomiasis prevention and control. Furthermore, it offers an excellent opportunity to study the immune system of gastropods and their co-evolution with pathogenic organisms.
Topics: Animals; Humans; Schistosoma japonicum; Schistosomiasis; Biomphalaria; Bulinus; Schistosoma mansoni
PubMed: 38093363
DOI: 10.1186/s13071-023-06011-9 -
Medecine Sciences : M/S Apr 2009Aquatic snails play a key role in the transmission of parasites such as the human blood or liver flukes (Schistosomes and Fasciola sp.). During the last decade,... (Review)
Review
Aquatic snails play a key role in the transmission of parasites such as the human blood or liver flukes (Schistosomes and Fasciola sp.). During the last decade, particular efforts have been made by a small number of scientists to progress in our understanding of the molecular mechanisms underlying snail immune responses and/or host parasite interactions. Complementary approaches using the gastropod snail Biomphalaria glabrata, an intermediate host of Schistosoma mansoni, have yielded a number of unexpected results such as the existence of highly diversified pathogen-binding proteins (FREPs), or potential immune regulators similar to mammalian cytokines. Although molecular immune processes largely remain to be elucidated, accumulating data support the idea that snail innate immunity is much more complex than originally thought.
Topics: Animals; Biomphalaria; Disease Vectors; Fasciola; Gene Expression Profiling; Hemocytes; Host-Parasite Interactions; Humans; Immunity, Innate; Immunoglobulins; Immunologic Memory; Larva; Life Cycle Stages; Models, Immunological; Proteome; Schistosoma mansoni; Schistosomiasis; Snails
PubMed: 19409193
DOI: 10.1051/medsci/2009254399 -
Brazilian Journal of Biology = Revista... 2023Schistosomiasis is a neglected tropical disease caused by parasitic worms of several species of the genus Schistosoma. Transmission occurs by parasitic larvae that stay... (Review)
Review
Schistosomiasis is a neglected tropical disease caused by parasitic worms of several species of the genus Schistosoma. Transmission occurs by parasitic larvae that stay in freshwater snails of the genus Biomphalaria. Thus, the search for new products that are biodegradable has increased the interest in products of plant origin. The aim of this article is to review the isolated substances from natural products that showed molluscicidal activity against the species Biomphalaria glabrata in order to reevaluate the most promising prototypes and update the progress of research to obtain a new molluscicide. We perform searches using scientific databases, such as Scientific Electronic Library Online (SciELO), Google schoolar, PUBMED, Web of Science and Latin American and Caribbean Literature on Health Sciences (LILACS). From 2000 to 2022, using the keywords "isolated substances", "molluscicidal activity" and "Biomphalaria glabrata". In the present study, it was possible to observe 19 promising molluscicidal molecules with a lethal concentration below 20 µg/mL. Of these promising isolates, only 5 isolates had the CL90 calculated and within the value recommended by WHO: Benzoic acid, 2',4',6'-Trihydroxydihydrochalcone, Divaricatic acid, Piplartine and 2-hydroxy-1,4-naphthoquinone (Lapachol). We conclude that beyond a few results in the area, the researches don't follow the methodological pattern (exposure time and measure units, toxicity test), in this way, as they don't follow a pattern on the result's exposure (LC), not following, in sum, the recommended by WHO.
Topics: Animals; Biomphalaria; Biological Products; Snails; Molluscacides
PubMed: 37283371
DOI: 10.1590/1519-6984.266526 -
Parasites & Vectors Feb 2023Biomphalaria glabrata is one of the main intermediate hosts of Schistosoma mansoni, the most widespread species of Schistosoma. Our previous studies proved that...
BACKGROUND
Biomphalaria glabrata is one of the main intermediate hosts of Schistosoma mansoni, the most widespread species of Schistosoma. Our previous studies proved that alternative oxidase (AOX), the terminal oxidase in the mitochondrial respiratory chain, widely exists in several species of intermediate host snails of Schistosoma. Meanwhile, inhibition of AOX activity in Oncomelania hupensis snails could dramatically enhance the molluscicidal effect of niclosamide. As a hermaphroditic aquatic mollusc, the high fecundity and population density of B. glabrata increase the difficulty of snail control, which is one of the critical strategies for schistosomiasis elimination. The present study aimed to investigate the possible role of AOX in the development and fecundity of B. glabrata snail, which could be manipulated more manageable than other species of intermediate host snails of Schistosoma.
METHODS
The dynamic expression of the AOX gene was investigated in different developmental stages and tissues of B. glabrata, with morphological change and oviposition behaviour observed from juvenile to adult snails. Furtherly, dsRNA-mediated knockdown of BgAOX mRNA and the AOX protein activity inhibiting was performed to investigate the effect of AOX on the development and oviposition of snails.
RESULTS
The BgAOX gene expression profile is highly related to the development from late juveniles to adults, especially to the reproductive system of snails, with a positive correlation of 0.975 between egg production and BgAOX relative expression in ovotestis of snails. The inhibition of BgAOX at the transcriptional level and AOX activity could efficiently inhibit snail growth. However, the interference at the BgAOX protein activity level led to more severe tissue damage and more significant inhibition of oviposition than at the transcriptional level. This inhibition of growth and oviposition decreased gradually with the increase in the snail size.
CONCLUSIONS
The inhibition of AOX could efficiently disrupt the development and oviposition of B. glabrata snails, and the intervention targeting AOX at the juvenile stage is more effective for snails. This investigation explored the role of AOX in the growth and development of snails. It would benefit snail control in the future by providing a potential target while using molluscicides more efficiently.
Topics: Animals; Female; Biomphalaria; Oviposition; Schistosoma mansoni; Oxidoreductases
PubMed: 36804043
DOI: 10.1186/s13071-022-05642-8 -
Parasites & Vectors Feb 2021Schistosomiasis is a neglected tropical disease endemic in 54 countries. A major Schistosoma species, Schistosoma mansoni, is sustained via a life cycle that includes...
BACKGROUND
Schistosomiasis is a neglected tropical disease endemic in 54 countries. A major Schistosoma species, Schistosoma mansoni, is sustained via a life cycle that includes both human and snail hosts. Mathematical models of S. mansoni transmission, used to elucidate the complexities of the transmission cycle and estimate the impact of intervention efforts, often focus primarily on the human host. However, S. mansoni incurs physiological costs in snails that vary with the age of the snail when first infected. Snail demography and the age of snail infection could thus affect the force of infection experienced by humans, which is frequently used to predict the impact of various control strategies.
METHODS
To address how these snail host and parasite interactions influence model predictions, we developed deterministic models of schistosomiasis transmission that include varying complexity in the snail population age structure. Specifically, we examined how model outputs, such as schistosome prevalence in human and snail populations, respond to the inclusion of snail age structure.
RESULTS
Our models suggest that snail population age structure modifies the force of infection experienced by humans and the relationship between snail infection prevalence and corresponding human infection prevalence. There are significant differences in estimated snail infection, cercarial density and mean worm burden between models without snail population dynamics and those with snail populations, and between models with a homogeneous snail population and those with age stratification. The variation between finely age-stratified snail populations and those grouped into only juvenile and adult life stages is, however, minimal.
CONCLUSIONS
These results indicate that including snails and snail age structure in a schistosomiasis transmission model alters the relationship between snail and human infection prevalence. This highlights the importance of accounting for a heterogeneous intermediate host population in models of schistosomiasis transmission where the impact of proposed control measures is being considered.
Topics: Animal Distribution; Animals; Biomphalaria; Humans; Models, Theoretical; Prevalence; Schistosomiasis
PubMed: 33536054
DOI: 10.1186/s13071-021-04587-8 -
Frontiers in Immunology 2022Schistosomiasis, caused by infection with digenetic trematodes, is one of the deadliest neglected tropical diseases in the world. The lifecycle involves the miracidial...
Schistosomiasis, caused by infection with digenetic trematodes, is one of the deadliest neglected tropical diseases in the world. The lifecycle involves the miracidial infection of an intermediate freshwater snail host, such as . Dispersing snail host-derived miracidia attractants has been considered a method of minimising intermediate host infections and, by extension, human schistosomiasis. The attractiveness of to miracidia is known to be reduced following infection; however, the relationship between duration of infection and attractiveness is unclear. Excretory-secretory proteins (ESPs) most abundant in attractive snail conditioned water (SCW) are key candidates to function as miracidia attractants. This study analysed SCW from that were naïve (uninfected) and at different time-points post-miracidia exposure (PME; 16h, 1-week, 2-weeks and 3-weeks PME) to identify candidate ESPs mediating miracidia behaviour change, including aggregation and chemoklinokinesis behaviour (random motion, including slowdown and increased turning rate and magnitude). Miracidia behaviour change was only observed post-addition of naïve and 3W-PME SCW, with other treatments inducing significantly weaker behaviour changes. Therefore, ESPs were considered attractant candidates if they were shared between naïve and 3W-PME SCW (or exclusive to the former), contained a predicted N-terminal signal peptide and displayed low identity (<50%) to known proteins outside of the genus. Using these criteria, a total of 6 ESP attractant candidates were identified, including acetylcholine binding protein-like proteins and uncharacterised proteins. Tissue-specific RNA-seq analysis of the genes encoding these 6 ESPs indicated relatively high gene expression within various tissues, including the foot, mantle and kidney. Acetylcholine binding protein-like proteins were highly promising due to their high abundance in naïve and 3W-PME SCW, high specificity to and high expression in the ovotestis, from which attractants have been previously identified. In summary, this study used proteomics, guided by behavioural assays, to identify miracidia attractant candidates that should be further investigated as potential biocontrols to disrupt miracidia infection and minimise schistosomiasis.
Topics: Animals; Humans; Biomphalaria; Schistosoma mansoni; Proteomics; Acetylcholine; Snails; Schistosomiasis; Proteins; Water; Protein Sorting Signals
PubMed: 36300127
DOI: 10.3389/fimmu.2022.954282 -
The Journal of Comparative Neurology Aug 2014Planorbid snails of the genus Biomphalaria are major intermediate hosts for the digenetic trematode parasite Schistosoma mansoni. Evidence suggests that levels of the... (Comparative Study)
Comparative Study
Localization of tyrosine hydroxylase-like immunoreactivity in the nervous systems of Biomphalaria glabrata and Biomphalaria alexandrina, intermediate hosts for schistosomiasis.
Planorbid snails of the genus Biomphalaria are major intermediate hosts for the digenetic trematode parasite Schistosoma mansoni. Evidence suggests that levels of the neurotransmitter dopamine (DA) are reduced during the course of S. mansoni multiplication and transformation within the snail. This investigation used immunohistochemical methods to localize tyrosine hydroxylase (TH), the rate-limiting enzyme in the biosynthesis of catecholamines, in the nervous system of Biomphalaria. The two species examined, Biomphalaria glabrata and Biomphalaria alexandrina, are the major intermediate hosts for S. mansoni in sub-Saharan Africa, where more than 90% of global cases of human intestinal schistosomiasis occur. TH-like immunoreactive (THli) neurons were distributed throughout the central nervous system (CNS) and labeled fibers were present in all commissures, connectives, and nerves. Some asymmetries were observed, including a large distinctive neuron (LPeD1) in the pedal ganglion described previously in several pulmonates. The majority of TH-like immunoreactive neurons were detected in the peripheral nervous system (PNS), especially in lip and foot regions of the anterior integument. Independent observations supporting the dopaminergic phenotype of THli neurons included 1) block of LPeD1 synaptic signaling by the D2/3 antagonist sulpiride, and 2) the similar localization of aqueous aldehyde (FaGlu)-induced fluorescence. The distribution of THli neurons indicates that, as in other gastropods, dopamine functions as a sensory neurotransmitter and in the regulation of feeding and reproductive behaviors in Biomphalaria. It is hypothesized that infection could stimulate transmitter release from dopaminergic sensory neurons and that dopaminergic signaling could contribute to modifications of both host and parasite behavior.
Topics: Animals; Biomphalaria; Catecholamines; Central Nervous System; Coloring Agents; Dopamine; Dopamine Antagonists; Formaldehyde; Ganglia, Invertebrate; Glutaral; Immunohistochemistry; Neurons; Peripheral Nervous System; Schistosoma mansoni; Species Specificity; Sulpiride; Synaptic Transmission; Tyrosine 3-Monooxygenase
PubMed: 24477836
DOI: 10.1002/cne.23548 -
BMC Genomics Dec 2008Biomphalaria glabrata is an intermediate snail host for Schistosoma mansoni, one of the important schistosomes infecting man. B. glabrata/S. mansoni provides a useful...
Biomphalaria glabrata transcriptome: cDNA microarray profiling identifies resistant- and susceptible-specific gene expression in haemocytes from snail strains exposed to Schistosoma mansoni.
BACKGROUND
Biomphalaria glabrata is an intermediate snail host for Schistosoma mansoni, one of the important schistosomes infecting man. B. glabrata/S. mansoni provides a useful model system for investigating the intimate interactions between host and parasite. Examining differential gene expression between S. mansoni-exposed schistosome-resistant and susceptible snail lines will identify genes and pathways that may be involved in snail defences.
RESULTS
We have developed a 2053 element cDNA microarray for B. glabrata containing clones from ORESTES (Open Reading frame ESTs) libraries, suppression subtractive hybridization (SSH) libraries and clones identified in previous expression studies. Snail haemocyte RNA, extracted from parasite-challenged resistant and susceptible snails, 2 to 24 h post-exposure to S. mansoni, was hybridized to the custom made cDNA microarray and 98 differentially expressed genes or gene clusters were identified, 94 resistant-associated and 4 susceptible-associated. Quantitative PCR analysis verified the cDNA microarray results for representative transcripts. Differentially expressed genes were annotated and clustered using gene ontology (GO) terminology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis. 61% of the identified differentially expressed genes have no known function including the 4 susceptible strain-specific transcripts. Resistant strain-specific expression of genes implicated in innate immunity of invertebrates was identified, including hydrolytic enzymes such as cathepsin L, a cysteine proteinase involved in lysis of phagocytosed particles; metabolic enzymes such as ornithine decarboxylase, the rate-limiting enzyme in the production of polyamines, important in inflammation and infection processes, as well as scavenging damaging free radicals produced during production of reactive oxygen species; stress response genes such as HSP70; proteins involved in signalling, such as importin 7 and copine 1, cytoplasmic intermediate filament (IF) protein and transcription enzymes such as elongation factor 1alpha and EF-2.
CONCLUSION
Production of the first cDNA microarray for profiling gene expression in B. glabrata provides a foundation for expanding our understanding of pathways and genes involved in the snail internal defence system (IDS). We demonstrate resistant strain-specific expression of genes potentially associated with the snail IDS, ranging from signalling and inflammation responses through to lysis of proteinacous products (encapsulated sporocysts or phagocytosed parasite components) and processing/degradation of these targeted products by ubiquitination.
Topics: Animals; Biomphalaria; Computational Biology; DNA, Complementary; Gene Expression Profiling; Genes, Helminth; Hemocytes; Microarray Analysis; Schistosoma mansoni; Schistosomiasis mansoni
PubMed: 19114004
DOI: 10.1186/1471-2164-9-634 -
Frontiers in Immunology 2022Disruptions to reproductive health in wildlife species inhabiting polluted environments is often found to occur alongside compromised immunity. However, research on...
Disruptions to reproductive health in wildlife species inhabiting polluted environments is often found to occur alongside compromised immunity. However, research on impacts of aquatic pollution on freshwater mollusc immune responses is limited despite their importance as vectors of disease (Schistosomiasis) in humans, cattle and wild mammals. We developed an 'tool-kit' of well-characterized quantitative immune tests using hemocytes. We exposed hemocytes to environmentally-relevant concentrations of common aquatic pollutants (17β-estradiol, Bisphenol-A and p,p'-DDE) and measured key innate immune responses including motility, phagocytosis and encapsulation. Additionally, we tested an extract of a typical domestic tertiary treated effluent as representative of a 'real-world' mixture of chemicals. Encapsulation responses were stimulated by p,p'-DDE at low doses but were suppressed at higher doses. Concentrations of BPA (above 200 ng/L) and p,p'-DDE (above 500 ng/L) significantly inhibited phagocytosis compared to controls, whilst hemocyte motility was reduced by all test chemicals and the effluent extract in a dose-dependent manner. All responses occurred at chemical concentrations considered to be below the cytotoxic thresholds of hemocytes. This is the first time a suite of tests has been developed specifically in with the purpose of investigating the impacts of chemical pollutants and an effluent extract on immunity. Our findings indicate that common aquatic pollutants alter innate immune responses in , suggesting that pollutants may be a critical, yet overlooked, factor impacting disease by modulating the dynamics of parasite transmission between molluscs and humans.
Topics: Animals; Biomphalaria; Cattle; Dichlorodiphenyl Dichloroethylene; Environmental Pollutants; Estradiol; Hemocytes; Humans; Mammals; Phagocytosis; Schistosoma mansoni
PubMed: 36159819
DOI: 10.3389/fimmu.2022.839746 -
Parasites & Vectors Sep 2019Schistosomiasis is a harmful neglected tropical disease caused by infection with Schistosoma spp., such as Schistosoma mansoni. Schistosoma must transition within a... (Comparative Study)
Comparative Study
BACKGROUND
Schistosomiasis is a harmful neglected tropical disease caused by infection with Schistosoma spp., such as Schistosoma mansoni. Schistosoma must transition within a molluscan host to survive. Chemical analyses of schistosome-molluscan interactions indicate that host identification involves chemosensation, including naïve host preference. Proteomic technique advances enable sophisticated comparative analyses between infected and naïve snail host proteins. This study aimed to compare resistant, susceptible and naïve Biomphalaria glabrata snail-conditioned water (SCW) to identify potential attractants and deterrents.
METHODS
Behavioural bioassays were performed on S. mansoni miracidia to compare the effects of susceptible, F1 resistant and naïve B. glabrata SCW. The F1 resistant and susceptible B. glabrata SCW excretory-secretory proteins (ESPs) were fractionated using SDS-PAGE, identified with LC-MS/MS and compared to naïve snail ESPs. Protein-protein interaction (PPI) analyses based on published studies (including experiments, co-expression, text-mining and gene fusion) identified S. mansoni and B. glabrata protein interaction. Data are available via ProteomeXchange with identifier PXD015129.
RESULTS
A total of 291, 410 and 597 ESPs were detected in the susceptible, F1 resistant and naïve SCW, respectively. Less overlap in ESPs was identified between susceptible and naïve snails than F1 resistant and naïve snails. F1 resistant B. glabrata ESPs were predominately associated with anti-pathogen activity and detoxification, such as leukocyte elastase and peroxiredoxin. Susceptible B. glabrata several proteins correlated with immunity and anti-inflammation, such as glutathione S-transferase and zinc metalloproteinase, and S. mansoni sporocyst presence. PPI analyses found that uncharacterised S. mansoni protein Smp_142140.1 potentially interacts with numerous B. glabrata proteins.
CONCLUSIONS
This study identified ESPs released by F1 resistant, susceptible and naïve B. glabrata to explain S. mansoni miracidia interplay. Susceptible B. glabrata ESPs shed light on potential S. mansoni miracidia deterrents. Further targeted research on specific ESPs identified in this study could help inhibit B. glabrata and S. mansoni interactions and stop human schistosomiasis.
Topics: Animals; Biomphalaria; Chromatography, Liquid; Electrophoresis, Polyacrylamide Gel; Host-Parasite Interactions; Proteins; Proteomics; Schistosoma mansoni; Tandem Mass Spectrometry
PubMed: 31521183
DOI: 10.1186/s13071-019-3708-0