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Sample records for human schistosoma japonicum

  1. Developmental gene expression profiles of the human pathogen Schistosoma japonicum

    PubMed Central

    Gobert, Geoffrey N; Moertel, Luke; Brindley, Paul J; McManus, Donald P

    2009-01-01

    Background The schistosome blood flukes are complex trematodes and cause a chronic parasitic disease of significant public health importance worldwide, schistosomiasis. Their life cycle is characterised by distinct parasitic and free-living phases involving mammalian and snail hosts and freshwater. Microarray analysis was used to profile developmental gene expression in the Asian species, Schistosoma japonicum. Total RNAs were isolated from the three distinct environmental phases of the lifecycle – aquatic/snail (eggs, miracidia, sporocysts, cercariae), juvenile (lung schistosomula and paired but pre-egg laying adults) and adult (paired, mature males and egg-producing females, both examined separately). Advanced analyses including ANOVA, principal component analysis, and hierarchal clustering provided a global synopsis of gene expression relationships among the different developmental stages of the schistosome parasite. Results Gene expression profiles were linked to the major environmental settings through which the developmental stages of the fluke have to adapt during the course of its life cycle. Gene ontologies of the differentially expressed genes revealed a wide range of functions and processes. In addition, stage-specific, differentially expressed genes were identified that were involved in numerous biological pathways and functions including calcium signalling, sphingolipid metabolism and parasite defence. Conclusion The findings provide a comprehensive database of gene expression in an important human pathogen, including transcriptional changes in genes involved in evasion of the host immune response, nutrient acquisition, energy production, calcium signalling, sphingolipid metabolism, egg production and tegumental function during development. This resource should help facilitate the identification and prioritization of new anti-schistosome drug and vaccine targets for the control of schistosomiasis. PMID:19320991

  2. Nitric oxide blocks the development of the human parasite Schistosoma japonicum.

    PubMed

    Shen, Jia; Lai, De-Hua; Wilson, R Alan; Chen, Yun-Fu; Wang, Li-Fu; Yu, Zi-Long; Li, Mei-Yu; He, Ping; Hide, Geoff; Sun, Xi; Yang, Ting-Bao; Wu, Zhong-Dao; Ayala, Francisco J; Lun, Zhao-Rong

    2017-09-19

    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.

  3. A spatial analysis of human Schistosoma japonicum infections in Hubei, China, during 2009-2014.

    PubMed

    Zhu, Hong; Cai, Shun-Xiang; Liu, Jian-Bing; Tu, Zu-Wu; Xia, Jing; Shan, Xiao-Wei; Qiu, Juan; Jiang, Yong; Xiao, Ying; Tang, Li; Huang, Xi-Bao

    2016-10-04

    The province of Hubei is located in the middle of China, near the middle and lower reaches of the River Yangtze, and is an area where schistosomiasis is endemic. It is challenging to control this disease in this environment, and it would be useful to identify clusters of infection and transmission, as well as their distributions during recent years. Therefore, this study aimed to analyze the spatial distribution of schistosomiasis in Hubei, in order to facilitate the effective control and elimination of this disease. We collected schistosomiasis surveillance data from all endemic counties in Hubei during 2009-2014. A geographical information system (ArcGIS, version 10.1) was used to link the counties' geographical data with the epidemiological data, and the spatial scanning method (FleXScan v3.1.2) was used to identify spatial clusters of human infections with Schistosoma japonicum. In Hubei, patients who exhibited stool test results that were positive for S. japonicum accounted for > 50 % of all cases in China during 2009-2014. However, each endemic county in Hubei exhibited a declining trend in the number of human S. japonicum infections during the study period. The ArcGIS analyses revealed that the middle reaches of the River Yangtze were highly endemic for S. japonicum infections. Spatial scan analyses revealed the following infection clusters: two clusters in ten counties during 2009, two clusters in nine counties during 2010, three clusters in 12 counties during 2011, two clusters in 12 counties during both 2012 and 2013 and two clusters in ten counties during 2014. Most of the cluster regions were located in the lake and marshland regions along the basins of the River Yangtze. We successfully identified schistosomiasis clusters at the county level in Hubei during 2009-2014, and our results revealed that the clusters were typically located in lake and marshland regions. These data may be useful for controlling and eliminating schistosomiasis in other high

  4. Familial aggregation of human infection with Schistosoma japonicum in the Poyang Lake region, China

    PubMed Central

    Ellis, Magda K.; Li, Yuesheng; Rong, Zhu; Chen, Honggen; McManus, Donald P.

    2005-01-01

    Despite the success of extensive control measures that have been implemented in China for over 50 years, the number of individuals infected with Schistosoma japonicum remains high in the remaining endemic areas. A variance components analysis was undertaken to estimate the heritable and environmental components that contribute to S. japonicum infection in the Poyang Lake region of Jiangxi Province, PR China. The total target population was 3148 from four separate administrative villages. Two thousand seven hundred and five of these comprised 400 families ranging in size from 3 to 188. After adjustments were made for gender, water contact and past history of having had schistosomiasis, the heritable component was estimated to account for as much as 58% of the phenotype variation under the polygenic model. Household was not shown to be an important environmental factor. Incorporating village effects indicated that the results were valid for the total population. We conclude that genetic heritability in this region is high and plays an important role in determining risk of infection with S. japonicum. PMID:16321389

  5. Non-immune immunoglobulins shield Schistosoma japonicum from host immunorecognition.

    PubMed

    Wu, Chuang; Hou, Nan; Piao, Xianyu; Liu, Shuai; Cai, Pengfei; Xiao, Yan; Chen, Qijun

    2015-08-24

    Schistosomiasis is a major human parasitic disease with a global impact. Schistosoma japonicum, the most difficult to control, can survive within host veins for decades. Mechanisms of immune evasion by the parasite, including antigenic variation and surface masking, have been implicated but not well defined. In this study, we defined the immunoglobulin-binding proteomes of S. japonicum using human IgG, IgM, and IgE as the molecular bait for affinity purification, followed by protein identification by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Several proteins situated at the tegument of S. japonicum were able to nonselectively bind to the Fc domain of host immunoglobulins, indicating a mechanism for the avoidance of host immune attachment and recognition. The profile of the immunoglobulin-binding proteomes provides further clues for immune evasion mechanisms adopted by S. japonicum.

  6. Non-immune immunoglobulins shield Schistosoma japonicum from host immunorecognition

    PubMed Central

    Wu, Chuang; Hou, Nan; Piao, Xianyu; Liu, Shuai; Cai, Pengfei; Xiao, Yan; Chen, Qijun

    2015-01-01

    Schistosomiasis is a major human parasitic disease with a global impact. Schistosoma japonicum, the most difficult to control, can survive within host veins for decades. Mechanisms of immune evasion by the parasite, including antigenic variation and surface masking, have been implicated but not well defined. In this study, we defined the immunoglobulin-binding proteomes of S. japonicum using human IgG, IgM, and IgE as the molecular bait for affinity purification, followed by protein identification by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Several proteins situated at the tegument of S. japonicum were able to nonselectively bind to the Fc domain of host immunoglobulins, indicating a mechanism for the avoidance of host immune attachment and recognition. The profile of the immunoglobulin-binding proteomes provides further clues for immune evasion mechanisms adopted by S. japonicum. PMID:26299686

  7. Transmission of Schistosoma japonicum by humans and domestic animals in the Yangtze River valley, Anhui province, China.

    PubMed

    Wang, Tian-Ping; Vang Johansen, Maria; Zhang, Shi-Qing; Wang, Feng-Feng; Wu, Wei-Duo; Zhang, Gong-Hua; Pan, Xin-Ping; Ju, Yang; Ørnbjerg, Niels

    2005-01-01

    The aim of the present work was to assess the relative contribution to transmission of Schistosoma japonicum by humans and domestic animals in two villages in the Yangtze River valley in Anhui province, China. A cross-sectional survey was conducted to determine the prevalence and intensity of S. japonicum in humans, cattle, water buffaloes, horses, pigs, goats, dogs and cats. Additionally, for each host species the number of individuals and the mean faecal excretion per day was determined. Results showed that both prevalence and intensity of infection varied significantly between species and between the two villages and neither of the variables gave an adequate picture of the potential transmission. Total daily egg excretion was significantly higher in Chenqiao village compared with Guanghui village. Whereas humans were the main contributors to transmission of schistosomiasis in Guanghui village (80.4%), water buffaloes accounted for nearly 90% and goats for more than 5% of the transmission in Chenqiao village. Hence, the present study suggests that schistosomiasis transmission might vary significantly within Chinese farm districts and successful control should rely on prior transmission index determinations on major potential contributors rather than routine data of prevalence and intensity of infection. Further studies should determine the value of adding other transmission variables like egg hatchability and faecal deposition habits.

  8. Geographical distribution of human Schistosoma japonicum infection in The Philippines: tools to support disease control and further elimination

    PubMed Central

    Magalhães, Ricardo J Soares; Salamat, Maria Sonia; Leonardo, Lydia; Gray, Darren J; Carabin, Hélène; Halton, Kate; McManus, Donald P; Williams, Gail M; Rivera, Pilarita; Saniel, Ofelia; Hernandez, Leda; Yakob, Laith; McGarvey, Stephen; Clements, Archie

    2015-01-01

    Schistosoma japonicum infection is believed to be endemic in 28 of the 80 provinces of The Philippines and the most recent data on schistosomiasis prevalence have shown considerable variability between provinces. In order to increase the efficient allocation of parasitic disease control resources in the country, we aimed to describe the small-scale spatial variation in S. japonicum prevalence across The Philippines, quantify the role of the physical environment in driving the spatial variation of S. japonicum, and develop a predictive risk map of S. japonicum infection. Data on S. japonicum infection from 35,754 individuals across the country were geolocated at the barangay level and included in the analysis. The analysis was then stratified geographically for the regions of Luzon, the Visayas and Mindanao. Zero-inflated binomial Bayesian geostatistical models of S. japonicum prevalence were developed and diagnostic uncertainty was incorporated. Results of the analysis show that in the three regions, males and individuals aged ≥ 20 years had significantly higher prevalence of S. japonicum compared with females and children < 5 years. The role of the environmental variables differed between regions of The Philippines. Schistosoma japonicum infection was widespread in the Visayas whereas it was much more focal in Luzon and Mindanao. This analysis revealed significant spatial variation in the prevalence of S. japonicum infection in The Philippines. This suggests that a spatially targeted approach to schistosomiasis interventions, including mass drug administration, is warranted. When financially possible, additional schistosomiasis surveys should be prioritized for areas identified to be at high risk but which were under-represented in our dataset. PMID:25128879

  9. Geographical distribution of human Schistosoma japonicum infection in The Philippines: tools to support disease control and further elimination.

    PubMed

    Soares Magalhães, Ricardo J; Salamat, Maria Sonia; Leonardo, Lydia; Gray, Darren J; Carabin, Hélène; Halton, Kate; McManus, Donald P; Williams, Gail M; Rivera, Pilarita; Saniel, Ofelia; Hernandez, Leda; Yakob, Laith; McGarvey, Stephen; Clements, Archie

    2014-11-01

    Schistosoma japonicum infection is believed to be endemic in 28 of the 80 provinces of The Philippines and the most recent data on schistosomiasis prevalence have shown considerable variability between provinces. In order to increase the efficient allocation of parasitic disease control resources in the country, we aimed to describe the small-scale spatial variation in S. japonicum prevalence across The Philippines, quantify the role of the physical environment in driving the spatial variation of S. japonicum, and develop a predictive risk map of S. japonicum infection. Data on S. japonicum infection from 35,754 individuals across the country were geo-located at the barangay level and included in the analysis. The analysis was then stratified geographically for the regions of Luzon, the Visayas and Mindanao. Zero-inflated binomial Bayesian geostatistical models of S. japonicum prevalence were developed and diagnostic uncertainty was incorporated. Results of the analysis show that in the three regions, males and individuals aged ⩾20years had significantly higher prevalence of S. japonicum compared with females and children <5years. The role of the environmental variables differed between regions of The Philippines. Schistosoma japonicum infection was widespread in the Visayas whereas it was much more focal in Luzon and Mindanao. This analysis revealed significant spatial variation in the prevalence of S. japonicum infection in The Philippines. This suggests that a spatially targeted approach to schistosomiasis interventions, including mass drug administration, is warranted. When financially possible, additional schistosomiasis surveys should be prioritised for areas identified to be at high risk but which were under-represented in our dataset. Copyright © 2014 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  10. Cross-sectional associations between intensity of animal and human infection with Schistosoma japonicum in Western Samar province, Philippines.

    PubMed Central

    McGarvey, Stephen T.; Carabin, Hélène; Balolong, Ernesto; Bélisle, Patrick; Fernandez, Tomas; Joseph, Lawrence; Tallo, Veronica; Gonzales, Ryan; Tarafder, Mushfiqur R.; Alday, Portia; Willingham, Arve Lee; Olveda, Remigio

    2006-01-01

    OBJECTIVE: To estimate the association between the intensity of animal infection with Schistosoma japonicum and human infection in Western Samar province, the Philippines. METHODS: We conducted an observational cross-sectional study of 1425 households in 50 villages. Stool samples were collected on each of 1-3 days from 5623 humans, 1275 cats, 1189 dogs, 1899 pigs, 663 rats and 873 water buffalo. Intensity of infection with S. japonicum was measured by the number of eggs per gram (EPG). Egg counts were done using the Kato-Katz method. We used a Bayesian hierarchical cumulative logit model, with adjustments for age, sex, occupation and measurement error. FINDINGS: The adjusted proportions of humans lightly infected (classified as 1-100 EPG) was 17.7% (95% Bayesian credible interval = 15.3-20.2%); the proportion classified as at least moderately infected (>100 EPG) was 3.2% (2.2-4.6%). The crude parasitological results for animals indicated that 37 cats (2.9%), 228 dogs (19.2%), 39 pigs (2.1%), 199 rats (30.0%) and 28 water buffalo (3.2%) were infected. In univariate analyses the odds ratios corresponding to a unit increase in the mean number of EPG at the village-level in dogs was 1.05 (1.01-1.09), in cats 1.35 (1.02-1.78), in pigs 1.16 (0.24- 5.18) and in rats 1.00 (1.00-1.01). Mean EPG values in cats, dogs, pigs and rats were correlated with one another. This confounding made interpreting the odds ratios difficult, but the odds ratios for dogs and cats were more consistent. CONCLUSION: S. japonicum is endemic in areas of the Philippines despite implementation of control programmes. This may be due to the association of infections in dogs and cats with human infections. Infection control in dogs and cats is challenging, and there is a need to develop new methods to control transmission across all species. PMID:16799728

  11. Non-equilibrium plasma prevention of Schistosoma japonicum transmission

    NASA Astrophysics Data System (ADS)

    Wang, Xing-Quan; Wang, Feng-Peng; Chen, Wei; Huang, Jun; Bazaka, Kateryna; Ostrikov, Kostya (Ken)

    2016-10-01

    Schistosoma japonicum is a widespread human and animal parasite that causes intestinal and hepatosplenic schistosomiasis linked to colon, liver and bladder cancers, and anemia. Estimated 230 million people are currently infected with Schistosoma spp, with 779 million people at risk of contracting the parasite. Infection occurs when a host comes into contact with cercariae, a planktonic larval stage of the parasite, and can be prevented by inactivating the larvae, commonly by chemical treatment. We investigated the use of physical non-equilibrium plasma generated at atmospheric pressure using custom-made dielectric barrier discharge reactor to kill S. japonicum cercariae. Survival rate decreased with treatment time and applied power. Plasmas generated in O2 and air gas discharges were more effective in killing S. japonicum cercariae than that generated in He, which is directly related to the mechanism by which cercariae are inactivated. Reactive oxygen species, such as O atoms, abundant in O2 plasma and NO in air plasma play a major role in killing of S. japonicum cercariae via oxidation mechanisms. Similar level of efficacy is also shown for a gliding arc discharge plasma jet generated in ambient air, a system that may be more appropriate for scale-up and integration into existing water treatment processes.

  12. Non-equilibrium plasma prevention of Schistosoma japonicum transmission

    PubMed Central

    Wang, Xing-Quan; Wang, Feng-Peng; Chen, Wei; Huang, Jun; Bazaka, Kateryna; Ostrikov, Kostya (Ken)

    2016-01-01

    Schistosoma japonicum is a widespread human and animal parasite that causes intestinal and hepatosplenic schistosomiasis linked to colon, liver and bladder cancers, and anemia. Estimated 230 million people are currently infected with Schistosoma spp, with 779 million people at risk of contracting the parasite. Infection occurs when a host comes into contact with cercariae, a planktonic larval stage of the parasite, and can be prevented by inactivating the larvae, commonly by chemical treatment. We investigated the use of physical non-equilibrium plasma generated at atmospheric pressure using custom-made dielectric barrier discharge reactor to kill S. japonicum cercariae. Survival rate decreased with treatment time and applied power. Plasmas generated in O2 and air gas discharges were more effective in killing S. japonicum cercariae than that generated in He, which is directly related to the mechanism by which cercariae are inactivated. Reactive oxygen species, such as O atoms, abundant in O2 plasma and NO in air plasma play a major role in killing of S. japonicum cercariae via oxidation mechanisms. Similar level of efficacy is also shown for a gliding arc discharge plasma jet generated in ambient air, a system that may be more appropriate for scale-up and integration into existing water treatment processes. PMID:27739459

  13. Non-equilibrium plasma prevention of Schistosoma japonicum transmission.

    PubMed

    Wang, Xing-Quan; Wang, Feng-Peng; Chen, Wei; Huang, Jun; Bazaka, Kateryna; Ostrikov, Kostya Ken

    2016-10-14

    Schistosoma japonicum is a widespread human and animal parasite that causes intestinal and hepatosplenic schistosomiasis linked to colon, liver and bladder cancers, and anemia. Estimated 230 million people are currently infected with Schistosoma spp, with 779 million people at risk of contracting the parasite. Infection occurs when a host comes into contact with cercariae, a planktonic larval stage of the parasite, and can be prevented by inactivating the larvae, commonly by chemical treatment. We investigated the use of physical non-equilibrium plasma generated at atmospheric pressure using custom-made dielectric barrier discharge reactor to kill S. japonicum cercariae. Survival rate decreased with treatment time and applied power. Plasmas generated in O2 and air gas discharges were more effective in killing S. japonicum cercariae than that generated in He, which is directly related to the mechanism by which cercariae are inactivated. Reactive oxygen species, such as O atoms, abundant in O2 plasma and NO in air plasma play a major role in killing of S. japonicum cercariae via oxidation mechanisms. Similar level of efficacy is also shown for a gliding arc discharge plasma jet generated in ambient air, a system that may be more appropriate for scale-up and integration into existing water treatment processes.

  14. Curupira-1 and Curupira-2, two novel Mutator-like DNA transposons from the genomes of human parasites Schistosoma mansoni and Schistosoma japonicum.

    PubMed

    Jacinto, Daniele S; Muniz, Heloisa Dos Santos; Venancio, Thiago M; Wilson, R Alan; Verjovski-Almeida, Sergio; Demarco, Ricardo

    2011-08-01

    Transposons of the Mutator superfamily have been widely described in plants, but only recently have metazoan organisms been shown to harbour them. In this work we describe novel Mutator superfamily transposons from the genomes of the human parasites Schistosoma mansoni and S. japonicum, which we name Curupira-1 and Curupira-2. Curupira elements do not have Terminal Inverted Repeats (TIRs) at their extremities and generate Target Site Duplications (TSDs) of 9 base pairs. Curupira-2 transposons code for a conserved transposase and SWIM zinc finger domains, while Curupira-1 elements comprise these same domains plus a WRKY zinc finger. Alignment of transcript sequences from both elements back to the genomes indicates that they are subject to splicing to produce mature transcripts. Phylogenetic analyses indicate that these transposons represent a new lineage of metazoan Mutator-like elements with characteristics that are distinct from the recently described Phantom elements. Description of these novel schistosome transposons provides new insights in the evolution of transposable elements in schistosomes.

  15. Cloning the genes and DNA binding properties of High Mobility Group B1 (HMGB1) proteins from the human blood flukes Schistosoma mansoni and Schistosoma japonicum.

    PubMed

    de Oliveira, Francisco Meirelles Bastos; de Abreu da Silva, Isabel Caetano; Rumjanek, Franklin David; Dias-Neto, Emmanuel; Guimarães, Pedro Edson Moreira; Verjovski-Almeida, Sergio; Stros, Michal; Fantappié, Marcelo Rosado

    2006-08-01

    The parasitic helminth Schistosoma mansoni contains three HMGB proteins, HMGB1, HMGB2 and HMGB3, of primary amino acid sequences highly similar to vertebrate proteins. In this report we describe the characterization of the HMGB1 proteins and their genes from S. mansoni and Schistosoma japonicum. The deduced amino acid sequences of HMGB1 proteins from both schistosome species are identical, and comprise 176 residues. The proteins contain the two evolutionarily highly conserved HMG-box domains, A and B, exhibiting 60% similarity to mammalian HMGB1. Unlike the human HMGB1 which contains an unbroken run of 30 glutamic or aspartic residues, the SmHMGB1 or SjHMGB1 proteins possess unusually short acidic C-terminal tails (5 acidic residues interrupted by 2 serines). Southern hybridization and DNA sequencing revealed a single copy HMGB1 gene, composed of 3 exons and two introns, in S. mansoni. The exon/intron boundaries are identical to those of the human HMGB1 gene, with the exception that the second exon of the SmHMGB1 gene which is not split into two exons as in the human HMGB1 gene. RNA blot analysis revealed that the SmHMGB1 gene is constitutively expressed in similar levels both in male and female worms. The single-sized mRNA for SmHMGB1 is consistent with the size derived from the cDNA. Although DNA binding properties of SmHMGB1 (or SjHMGB1) protein seem to be similar to those previously reported with human HMGB1, i.e., preferential binding to supercoiled DNA over linear DNA, specific recognition of DNA four-way junctions, DNA-induced supercoiling in the presence of topoisomerase I, and DNA bending, we have observed two important differences relative to those observed with the human HMGB1: (i) the inability of the isolated SmHMGB1 domain A to bend DNA (as revealed by T4 ligase-mediated circularization assay), and (ii) higher DNA supercoiling and bending potential of the SmHMGB1 protein as compared to its human counterpart. The latter finding may indicate that the

  16. Molecular Differentiation of Schistosoma japonicum and Schistosoma mekongi by Real-Time PCR with High Resolution Melting Analysis

    PubMed Central

    Kongklieng, Amornmas; Kaewkong, Worasak; Intapan, Pewpan M.; Sanpool, Oranuch; Janwan, Penchom; Thanchomnang, Tongjit; Lulitanond, Viraphong; Sri-Aroon, Pusadee; Limpanont, Yanin

    2013-01-01

    Human schistosomiasis caused by Schistosoma japonicum and Schistosoma mekongi is a chronic and debilitating helminthic disease still prevalent in several countries of Asia. Due to morphological similarities of cercariae and eggs of these 2 species, microscopic differentiation is difficult. High resolution melting (HRM) real-time PCR is developed as an alternative tool for the detection and differentiation of these 2 species. A primer pair was designed for targeting the 18S ribosomal RNA gene to generate PCR products of 156 base pairs for both species. The melting points of S. japonicum and S. mekongi PCR products were 84.5±0.07℃ and 85.7±0.07℃, respectively. The method permits amplification from a single cercaria or an egg. The HRM real-time PCR is a rapid and simple tool for differentiation of S. japonicum and S. mekongi in the intermediate and final hosts. PMID:24516269

  17. Invasion by schistosome cercariae: neglected aspects in Schistosoma japonicum.

    PubMed

    Ruppel, Andreas; Chlichlia, Katerina; Bahgat, Mahmoud

    2004-09-01

    Skin invasion by schistosome cercariae was recently discussed in Trends in Parasitology. However, only Schistosoma mansoni was considered, possibly because this species predominates in laboratory studies (at least outside China). One may be tempted to extrapolate from the "model" S. mansoni to other schistosomes, but Schistosoma japonicum must not be neglected. This schistosome is distinguishable from others (particularly S. mansoni) by virtue of its remarkable speed and success of migration, as well as by specific biochemical and immunological features. This leads to the hypothesis that S. japonicum is atypical with respect to the enzymes that facilitate skin penetration.

  18. Thioredoxin Glutathione Reductase as a Novel Drug Target: Evidence from Schistosoma japonicum

    PubMed Central

    Xie, ShuYing; Qian, ChunYan; Wang, Jie; Zhang, Wei; Yin, XuRen; Hua, ZiChun; Yu, ChuanXin

    2012-01-01

    Background Schistosomiasis remains a major public health concern affecting billions of people around the world. Currently, praziquantel is the only drug of choice for treatment of human schistosomiasis. The emergence of drug resistance to praziquantel in schistosomes makes the development of novel drugs an urgent task. Thioredoxin glutathione reductase (TGR) enzymes in Schistosoma mansoni and some other platyhelminths have been identified as alternative targets. The present study was designed to confirm the existense and the potential value of TGR as a target for development of novel antischistosomal agents in Schistosoma japonicum, a platyhelminth endemic in Asia. Methods and Findings After cloning the S. japonicum TGR (SjTGR) gene, the recombinant SjTGR selenoprotein was purified and characterized in enzymatic assays as a multifunctional enzyme with thioredoxin reductase (TrxR), glutathione reductase (GR) and glutaredoxin (Grx) activities. Immunological and bioinformatic analyses confirmed that instead of having separate TrxR and GR proteins in mammalian, S. japonicum only encodes TGR, which performs the functions of both enzymes and plays a critical role in maintaining the redox balance in this parasite. These results were in good agreement with previous findings in Schistosoma mansoni and some other platyhelminths. Auranofin, a known inhibitor against TGR, caused fatal toxicity in S. japonicum adult worms in vitro and reduced worm and egg burdens in S. japonicum infected mice. Conclusions Collectively, our study confirms that a multifunctional enzyme SjTGR selenoprotein, instead of separate TrxR and GR enzymes, exists in S. japonicum. Furthermore, TGR may be a potential target for development of novel agents against schistosomes. This assumption is strengthened by our demonstration that the SjTGR is an essential enzyme for maintaining the thiol-disulfide redox homeostasis of S. japonicum. PMID:22384025

  19. DNA Detection of Schistosoma japonicum: Diagnostic Validity of a LAMP Assay for Low-Intensity Infection and Effects of Chemotherapy in Humans

    PubMed Central

    Zhao, Bo; Wang, Yan-Yan; Cao, Yun; Zhang, Hui-Qin; Zhu, Xing-Quan; He, Yong-Kang; Xia, Chao-Ming

    2015-01-01

    Background Schistosomiasis has decreased significantly in prevalence and intensity of infection in China, thus more accurate and sensitive methods are desperately needed for the further control of schistosomiasis. The present work aimed to assess the utility of the loop-mediated isothermal amplification (LAMP) for detection of light intensity infection or false-negative patients and patients post-treatment, targeting the highly repetitive retrotransposon SjR2 of Schistosoma japonicum. Methodology/ Principal Findings LAMP was first assessed in rabbits with low intensity infection (EPG<10). Then 110 patient sera from Hunan Province, China, and 47 sera after treatment by praziquantel were used to evaluate the diagnostic validity of LAMP. Meanwhile, 42 sera from healthy individuals in a non-endemic area, and 60 sera from "healthy” residents who were identified as being negative for feces examination and immuno-methods in an endemic area were also examined. The results showed that LAMP could detect S. japonicum DNA in sera from rabbits at 3rd day post-infection. Following administration of praziquantel, the S. japonicum DNA in rabbit sera became negative at 10 weeks post-treatment. Of 110 sera from patients, LAMP showed 95.5% sensitivity, and even for 41 patients with less than 10 EPG, the sensitivity of LAMP still reached to 95.1%. For 47 patients after treatment, the negative conversion rate of S. japonicum DNA in patient sera increased from 23.4%, 61.7% to 83.0% at 3 months, 6 months and 9 months post-treatment, respectively. No false-positive result was obtained for 42 human sera from non-endemic area, while for the 60 “healthy” individuals from endemic area, 10 (16.7%) individuals were positive by LAMP, which suggested that these individuals might be false-negative patients. Conclusions/ Significance The present study demonstrated that the LAMP assay is sensitive, specific, and affordable, which would help reduce schistosomiasis transmission through targeted

  20. Biology and Control of Snail Intermediate Host of Schistosoma japonicum in The People's Republic of China.

    PubMed

    Li, Z-J; Ge, J; Dai, J-R; Wen, L-Y; Lin, D-D; Madsen, H; Zhou, X-N; Lv, S

    2016-01-01

    Schistosomiasis caused by Schistosoma japonicum is a severe parasitic disease in The People's Republic of China and imposed considerable burden on human and domestic animal health and socioeconomic development. The significant achievement in schistosomiasis control has been made in last 60years. Oncomelania hupensis as the only intermediate host of S. japonicum plays a key role in disease transmission. The habitat complexity of the snails challenges to effective control. In this review we share the experiences in control and research of O. hupensis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Cloning, expression, and partial characterization of FBPA from Schistosoma japonicum, a molecule on that the fluke may develop nutrition competition and immune evasion from human.

    PubMed

    Hu, Qiping; Xie, Huiqiong; Zhu, Shuyu; Liao, Dejun; Zhan, Tingzheng; Liu, Dengyu

    2015-09-01

    Carbohydrate metabolism is the most important physiological process for Schistosoma japonicum which resides in host. However, as a key glycolytic enzyme in carbohydrate metabolism, fructose-1,6-bisphosphate aldolase (FBPA), there is no study on its enzymatic kinetics and antigenic peptides. Here, we report the gene cloning, expression, purification, and kinetics of the FBPA from S. japonicum (sjFBPA). After cloning, sjFBPA gene was introduced into pET-28a and transformed BL21, and a soluble His6-sjFBPA was expressed and purified successfully at the expected molecular mass of ~45 kDa. We first reported that the diversities in IGS regions and the features of residues position 346 and 357-362 of sjFBPA may be conferred either through conformational changes influencing easily the active site from a distance and/or causing the C-terminal region to interact directly with the active site, which lead His6-sjFBPA to exhibit a higher specific activity of 197.43 units/mg and degrades FBP with a typical substrate inhibition model and a higher efficiency of k cat  = 6261.3/s and K m  = 0.061 μM than human aldolases, which might be the strategy that S. japonicum gaining energy and surviving in its environment with low concentration of carbohydrate, and benefitting to get more metabolic substances for parasites in nutrition competition with their host. sjFBPA exhibits a high similarity of 81.46 % with that of hosts, especially in antigenic peptide regions, and 14 of 15 antigenic peptides of sjFBPA were conserved to those of human aldolase A, B, and/or C with high identity (17, 16, or 16 antigenic peptides, respectively), which may result in a molecular mimicry of FBPA with that of host, and an immune evasion from their hosts. This work would supply an experimental base for using FBPA to prevent the schistosomiasis in the future.

  2. Exploring molecular variation in Schistosoma japonicum in China

    PubMed Central

    Young, Neil D.; Chan, Kok-Gan; Korhonen, Pasi K.; Min Chong, Teik; Ee, Robson; Mohandas, Namitha; Koehler, Anson V.; Lim, Yan-Lue; Hofmann, Andreas; Jex, Aaron R.; Qian, Baozhen; Chilton, Neil B.; Gobert, Geoffrey N.; McManus, Donald P.; Tan, Patrick; Webster, Bonnie L.; Rollinson, David; Gasser, Robin B.

    2015-01-01

    Schistosomiasis is a neglected tropical disease that affects more than 200 million people worldwide. The main disease-causing agents, Schistosoma japonicum, S. mansoni and S. haematobium, are blood flukes that have complex life cycles involving a snail intermediate host. In Asia, S. japonicum causes hepatointestinal disease (schistosomiasis japonica) and is challenging to control due to a broad distribution of its snail hosts and range of animal reservoir hosts. In China, extensive efforts have been underway to control this parasite, but genetic variability in S. japonicum populations could represent an obstacle to eliminating schistosomiasis japonica. Although a draft genome sequence is available for S. japonicum, there has been no previous study of molecular variation in this parasite on a genome-wide scale. In this study, we conducted the first deep genomic exploration of seven S. japonicum populations from mainland China, constructed phylogenies using mitochondrial and nuclear genomic data sets, and established considerable variation between some of the populations in genes inferred to be linked to key cellular processes and/or pathogen-host interactions. Based on the findings from this study, we propose that verifying intraspecific conservation in vaccine or drug target candidates is an important first step toward developing effective vaccines and chemotherapies against schistosomiasis. PMID:26621075

  3. Approaches to genotyping individual miracidia of Schistosoma japonicum

    PubMed Central

    Xiao, Ning; Remais, Justin V.; Brindley, Paul J.; Qiu, Dong-chuan; Carlton, Elizabeth J.; Li, Rong-zhi; Lei, Yang; Blair, David

    2013-01-01

    Molecular genetic tools are needed to address questions as to the source and dynamics of transmission of the human blood fluke Schistosoma japonicum in regions where human infections have re-emerged, and to characterize infrapopulations in individual hosts. The life-stage that interests us as a target for collecting genotypic data is the miracidium, a very small larval stage that consequently yields very little DNA for analysis. Here, we report the successful development of a multiplex format permitting genotyping of 17 microsatellite loci in four sequential multiplex reactions using a single miracidium held on a Whatman Classic FTA indicating card. This approach was successful after short storage periods, but after long storage (>4 years) considerable difficulty was encountered in multiplex genotyping, necessitating the use of whole genome amplification (WGA) methods. WGA applied to cards stored for long periods of time resulted in sufficient DNA for accurate and repeatable genotyping. Trials and tests of these methods, as well as application to some field-collected samples, are reported, along with discussion of the potential insights to be gained from such techniques. These include recognition of sibships among miracidia from a single host, and inference of the minimum number of worm pairs that might be present in a host. PMID:24013341

  4. A specific indel marker for the Philippines Schistosoma japonicum revealed by analysis of mitochondrial genome sequences.

    PubMed

    Li, Juan; Chen, Fen; Sugiyama, Hiromu; Blair, David; Lin, Rui-Qing; Zhu, Xing-Quan

    2015-07-01

    In the present study, near-complete mitochondrial (mt) genome sequences for Schistosoma japonicum from different regions in the Philippines and Japan were amplified and sequenced. Comparisons among S. japonicum from the Philippines, Japan, and China revealed a geographically based length difference in mt genomes, but the mt genomic organization and gene arrangement were the same. Sequence differences among samples from the Philippines and all samples from the three endemic areas were 0.57-2.12 and 0.76-3.85 %, respectively. The most variable part of the mt genome was the non-coding region. In the coding portion of the genome, protein-coding genes varied more than rRNA genes and tRNAs. The near-complete mt genome sequences for Philippine specimens were identical in length (14,091 bp) which was 4 bp longer than those of S. japonicum samples from Japan and China. This indel provides a unique genetic marker for S. japonicum samples from the Philippines. Phylogenetic analyses based on the concatenated amino acids of 12 protein-coding genes showed that samples of S. japonicum clustered according to their geographical origins. The identified mitochondrial indel marker will be useful for tracing the source of S. japonicum infection in humans and animals in Southeast Asia.

  5. Schistosoma japonicum infection induces macrophage polarization

    PubMed Central

    Xu, Jingwei; Zhang, Hao; Chen, Lin; Zhang, Donghui; Ji, Minjun; Wu, Haiwei; Wu, Guanling

    2014-01-01

    Abstract The role of macrophages (Mφ) as the first line of host defense is well accepted. These cells play a central role in orchestrating crucial functions during schistosomal infection. Thus, understanding the functional diversity of these cells in the process of infection as well as the mechanisms underlying these events is crucial for developing disease control strategies. In this study, we adopted a Mφ polarization recognition system. M1 macrophage was characterized by expressing CD16/32, IL-12 and iNOS. M2 macrophage was characterized by expressing CD206, IL-10 and arg-1. In vivo (mouse peritoneal macrophages of different infection stages were obtained) and in vitro (different S. japonicum antigens were used to stimulate RAW264.7) were characterized by using the above mentioned system. NCA and ACA stimulated RAW264.7 express significantly higher levels of IL-12 while significantly higher levels of IL-10 were detected after soluble egg antigen (SEA) stimulation. The results showed that dramatic changes of antigen in the microenvironment before and after egg production led to macrophage polarization. Furthermore, through TLR blocking experiments, the TLR4 signaling pathway was found to play a role in the process of macrophage polarization toward M1. Our data suggest that macrophage polarization during S. japonicum infection had significant effects on host immune responses to S. japonicum. PMID:25050114

  6. In vitro cultivation of Schistosoma japonicum-parasites and cells.

    PubMed

    Ye, Qing; Dong, Hui-Fen; Grevelding, Christoph G; Hu, Min

    2013-12-01

    Schistosomiasis is a serious parasitic zoonosis caused by blood-dwelling flukes of the genus Schistosoma. Understanding functions of genes and proteins of this parasite is important for uncovering this pathogen's complex biology, which will provide valuable information to design new strategies for schistosomiasis control. Effective applications of molecular tools reported to investigate schistosome gene function, such as inhibitor studies and transgenesis, rely on the developments of in vitro cultivation system of this parasite and cells. Besides the in vitro culture studies dealing with Schistosoma mansoni, there are also numerous excellent studies about the in vitro cultivation of Schistosoma japonicum, which were performed by Chinese researchers and published in Chinese journals. Nearly every stage of the life-cycle of S. japonicum, including miracidia, mother sporocysts, cercariae, schistosomula, and egg-laying adult worms, was employed for developing in vitro cultivation methods, being accompanied by the introduction of several media and supplements that helped to improve culture conditions. It was not only possible to generate mother sporocysts from miracidia in vitro, but also to obtain adult worms from cercariae through in vitro cultivation. The main obstacles to complete the life cycle of S. japonicum in the lab are the transition from mother sporocysts to cercariae, and the production of fertilized and completely developed eggs by adult worms generated in vitro. With regard to cells from S. japonicum, besides established isolation protocols and morphological observations, media optimizations were conducted by using different chemical reagents, biological supplements and physical treatment. Among these, mutagens like N-methyl-N-nitro-N-nitrosoguanidine and the addition of extracellular matrix were found to be able to induce mitogenic activities. Although enzyme activities or the level of silver-stained nucleolar region associated protein in cultured cells

  7. Ascending colon cancer associated with deposited ova of Schistosoma japonicum in non-endemic area.

    PubMed

    Nakatani, Kensuke; Kato, Takaharu; Okada, Shinichiro; Matsumoto, Risa; Nishida, Kazuhiro; Komuro, Hiroyasu; Iida, Maki; Tsujimoto, Shiro; Suganuma, Toshiyuki

    2016-01-01

    Some reports suggest the positive correlation between Schistosoma japonicum infection and colorectal cancer, however the sufficient evidence that supports a causal relationship between them has not been established. Japan used be an endemic area of S. japonicum infection for 40 years ago. But now all of Japan is a non-endemic area of S. japonicum infection. We report a case of ascending colon cancer associated with deposited ova of S. japonicum in non-endemic area.

  8. Cloning and in vitro characterization of a Schistosoma japonicum aquaglyceroporin that functions in osmoregulation

    PubMed Central

    Huang, Yuzheng; Li, Wei; Lu, Wuguang; Xiong, Chunrong; Yang, Yang; Yan, Huaijiang; Liu, Kun Connie; Cao, Peng

    2016-01-01

    As one of the three major human pathogens that cause schistosomiasis, Schistosoma japonicum is the only one that is endemic in China. Despite great progress on schistosomiasis control over the past 50 years in China, S. japonicum transmission still occurs in certain endemic regions, which causes significant public health problems and enormous economic losses. During different life stages, parasites are able to survive dramatic osmolality changes between its vector, fresh water, and mammal host. However, the molecular mechanism of parasite osmoregulation remains unknown. To address this challenging question, we report the first cloning of an S. japonicum aquaglyceroporin (SjAQP) from an isolate from Jiangsu province, China. Expressing SjAQP in Xenopus oocytes facilitated the permeation of water, glycerol, and urea. The water permeability of SjAQP was inhibited by 1 mM HgCl2, 3 mM tetraethylammonium, 1 mM ZnCl2, and 1 mM CuSO4. SjAQP was constitutively expressed throughout the S. japonicum life cycle, including in the egg, miracidia, cercaria, and adult stages. The highest expression was detected during the infective cercaria stage. Our results suggest that SjAQP plays a role in osmoregulation throughout the S. japonicum life cycle, especially during cercariae transformation, which enables parasites to survive osmotic challenges. PMID:27733755

  9. Identifying Schistosoma japonicum excretory/secretory proteins and their interactions with host immune system.

    PubMed

    Liao, Qi; Yuan, Xiongying; Xiao, Hui; Liu, Changning; Lv, Zhiyue; Zhao, Yi; Wu, Zhongdao

    2011-01-01

    Schistosoma japonicum is a major infectious agent of schistosomiasis. It has been reported that large number of proteins excreted and secreted by S. japonicum during its life cycle are important for its infection and survival in definitive hosts. These proteins can be used as ideal candidates for vaccines or drug targets. In this work, we analyzed the protein sequences of S. japonicum and found that compared with other proteins in S. japonicum, excretory/secretory (ES) proteins are generally longer, more likely to be stable and enzyme, more likely to contain immune-related binding peptides and more likely to be involved in regulation and metabolism processes. Based on the sequence difference between ES and non-ES proteins, we trained a support vector machine (SVM) with much higher accuracy than existing approaches. Using this SVM, we identified 191 new ES proteins in S. japonicum, and further predicted 7 potential interactions between these ES proteins and human immune proteins. Our results are useful to understand the pathogenesis of schistosomiasis and can serve as a new resource for vaccine or drug targets discovery for anti-schistosome.

  10. Correlation between hammerhead ribozyme-mediated eggshell protein gene cleavage and reproduction inhibition of Schistosoma japonicum

    PubMed Central

    LIANG, YU; ZHOU, YUELAN; YIN, WEIGUO; LI, YINGJU; YANG, QIULIN; GAO, YUAN; ZHANG, YUKUAI; YANG, YAOFEI; PENG, LI; XIAO, JIANHUA

    2012-01-01

    Schistosoma japonicum (S. japonicum) is an extremely harmful pathogen, which infects humans and causes severe public health problems. To date, no effective therapeutic drugs for this pathogen are available. In this study, we designed and constructed three hammerhead ribozymes targeting the eggshell protein gene of S. japonicum (SjESG). The cleavage activities of these three ribozymes were determined using cleavage experiments. The in vitro cleavage results showed that among the three synthesized ribozymes (Rz1, Rz2 and Rz3), Rz1 and Rz3 cleaved their target RNAs effectively. However, Rz2 did not cleave its target RNA detectably. The putative therapeutic roles of these three ribozymes to inhibit the reproduction of S. japonicum in mice were studied in vivo. Compared with the negative controls, Rz1 and Rz3 treatments resulted in increased levels of IFN-γ but decreased levels of IL-4 in mice. Rz2 affected levels of IFN-γ and IL-4 to degrees similar with those caused by the vector controls. In addition, Rz1 and Rz3 reduced the amounts of adult worms and eggs in the livers of mice more extensively than Rz2 and the vector controls. Altogether, these results suggest a correlation between the in vitro cleavage abilities of Rz1 and Rz3 and their roles in reproduction inhibition of S. japonicum. PMID:22246067

  11. Co-dispersal of the blood fluke Schistosoma japonicum and Homo sapiens in the Neolithic Age

    PubMed Central

    Yin, Mingbo; Zheng, Hong-Xiang; Su, Jing; Feng, Zheng; McManus, Donald P.; Zhou, Xiao-Nong; Jin, Li; Hu, Wei

    2015-01-01

    The global spread of human infectious diseases is of considerable public health and biomedical interest. Little is known about the relationship between the distribution of ancient parasites and that of their human hosts. Schistosoma japonicum is one of the three major species of schistosome blood flukes causing the disease of schistosomiasis in humans. The parasite is prevalent in East and Southeast Asia, including the People’s Republic of China, the Philippines and Indonesia. We studied the co-expansion of S. japonicum and its human definitive host. Phylogenetic reconstruction based on complete mitochondrial genome sequences showed that S. japonicum radiated from the middle and lower reaches of the Yangtze River to the mountainous areas of China, Japan and Southeast Asia. In addition, the parasite experienced two population expansions during the Neolithic agriculture era, coinciding with human migration and population growth. The data indicate that the advent of rice planting likely played a key role in the spread of schistosomiasis in Asia. Moreover, the presence of different subspecies of Oncomelania hupensis intermediate host snails in different localities in Asia allowed S. japonicum to survive in new rice-planting areas, and concurrently drove the intraspecies divergence of the parasite. PMID:26686813

  12. Excretory/secretory proteome of 14-day schistosomula, Schistosoma japonicum.

    PubMed

    Cao, Xiaodan; Fu, Zhiqiang; Zhang, Min; Han, Yanhui; Han, Qian; Lu, Ke; Li, Hao; Zhu, Chuangang; Hong, Yang; Lin, Jiaojiao

    2016-01-01

    Schistosomiasis remains a serious public health problem, with 200 million people infected and 779 million people at risk worldwide. The schistosomulum is the early stage of the complex lifecycle of Schistosoma japonicum in their vertebrate hosts, and is the main target of vaccine-induced protective immunity. Excretory/secretory (ES) proteins play a major role in host-parasite interactions and ES protein compositions of schistosomula of S. japonicum have not been characterized to date. In the present study, the proteome of ES proteins from 14 day schistosomula of S. japonicum was analyzed by liquid chromatography/tandem mass spectrometry and 713 unique proteins were finally identified. Gene ontology and pathway analysis revealed that identified proteins were mainly involved in carbohydrate metabolism, degradation, response to stimulus, oxidation-reduction, biological regulation and binding. Flow cytometry analysis demonstrated that thioredoxin peroxidase identified in this study had the effect on inhibiting MHCII and CD86 expression on LPS-activated macrophages. The present study provides insight into the growth and development of the schistosome in the final host and valuable information for screening vaccine candidates for schistosomiasis.

  13. Failure to induce resistance of Schistosoma japonicum to praziquantel.

    PubMed

    Yue, W J; Yu, S H; Xu, X J

    1990-03-01

    In order to explore the possible occurrence of inducing resistance of Schistosoma japonicum to praziquantel (PZQ), a set of animal experiments were carried out. Outbred mice (NIH strain), Anhui isolates of S. japonicum and Oncomelania hupensis were used. In one protocol five weeks after being infected with 48-52 cercariae, mice were orally dosed with PZQ 300 mg/kg, and killed 82 days later to isolate eggs from the liver. Snails were exposed to miracidia released from egg-hatching. F1 progeny were thus obtained through cercarial inoculation. The same scheme was applied for the establishment of the F2 generation. In another protocol two weeks after infection, PZQ 50 mg/kg/day was given to mice for 5 days. Eggs were collected 26-27 days post treatment and the identical procedures were adopted for F1 and F2 generations successively. Analysis of total worm and female worm reduction rates indicated that there was no significant difference between the sensitivity to PZQ of F1 and F2 progenies of S. japonicum and the parent worms.

  14. Synthesis and SAR studies of praziquantel derivatives with activity against Schistosoma japonicum.

    PubMed

    Wang, Wen-Long; Song, Li-Jun; Chen, Xia; Yin, Xu-Ren; Fan, Wen-Hua; Wang, Gu-Ping; Yu, Chuan-Xin; Feng, Bainian

    2013-07-31

    The synthesis and structure-activity relationship (SAR) studies of praziquantel derivatives with activity against adult Schistosoma japonicum are described. Several of them showed better worm killing activity than praziquantel and could serve as leads for further optimization.

  15. High Prevalence of Schistosoma japonicum Infection in Water Buffaloes in the Philippines Assessed by Real-Time Polymerase Chain Reaction

    PubMed Central

    Wu, Hai-Wei; Qin, Yuan-Fang; Chu, Kai; Meng, Rui; Liu, Yun; McGarvey, Stephen T.; Olveda, Remigio; Acosta, Luz; Ji, Min-Jun; Fernandez, Tomas; Friedman, Jennifer F.; Kurtis, Jonathan D.

    2010-01-01

    Difficulty in controlling human Schistosoma japonicum infection is partly attributed to the presence of non-human definitive hosts. Water buffaloes are a major reservoir for transmission of S. japonicum to humans in China. However, in the Philippines, reports based on microscopic examination of buffalo stool identified a low prevalence of S. japonicum, and mathematical models using these data concluded that water buffaloes are not a major reservoir for transmission of S. japonicum to humans. We collected stool from 81 buffaloes in Macanip, Leyte, the Philippines, and assayed for S. japonicum infection by the Danish Bilharziasis Laboratory technique, the Kato-Katz technique, miracidia hatching, and a highly validated real-time polymerase chain reaction. The prevalence defined by each assay was 3.7%, 3.7%, 0%, and 51.5% respectively. Our results demonstrate that microscopic-based techniques dramatically underestimate the prevalence of S. japonicum infection in water buffaloes in the Philippines and warrant reexamination of the role of bovines in transmission of S. japonicum to humans in the Philippines. PMID:20348514

  16. Is there a reduced sensitivity of dihydroartemisinin against praziquantel-resistant Schistosoma japonicum?

    PubMed

    Wang, Wei; Li, Hong-Jun; Qu, Guo-Li; Xing, Yun-Tian; Yang, Zhen-Kun; Dai, Jian-Rong; Liang, You-Sheng

    2014-01-01

    Praziquantel is currently the only drug of choice for the treatment of human schistosomiases. However, it has been proved that Schistosoma japonicum subjected to drug pressure may develop resistance to praziquantel. To evaluate the efficacy of dihydroartemisinin against praziquantel-resistant S. japonicum, mice infected with a praziquantel-resistant isolate and a praziquantel-susceptible isolate of S. japonicum were treated with dihydroartemisinin at a single oral dose of 300 mg/kg given once on each of 35-36 post-infection days, while infected but untreated mice served as controls. All mice were sacrificed 50 days post-infection, and the worm burden reductions were estimated. Administration of dihydroartemisinin at a single oral dose of 300 mg/kg on each of 35-36 post-infection days reduced total worm burdens of 69.8% and female worm burdens of 86% in mice infected with the praziquantel-susceptible isolate, and total worm burdens of 66.1% and female worm burdens of 85.1% in mice infected with the praziquantel-resistant isolate (both P values > 0.05). It is concluded that the sensitivity of artemisinin derivative dihydroartemisinin does not reduce in praziquantel-resistant S. japonicum.

  17. Having a pair: the key to immune evasion for the diploid pathogen Schistosoma japonicum

    PubMed Central

    Xu, Xindong; Sun, Jun; Zhang, Jingjing; Wellems, Dianne; Qing, Xiaoxing; McCutchan, Thomas; Pan, Weiqing

    2012-01-01

    Schistosomes, unlike malaria parasites, are in their diploid stage when targeted by the human immune system. Diploids can be either homozygous or heterozygous. The difference has profound significance for developing immunity and yet has not previously been addressed. We examined the implications of zygosity on immunity to a diploid pathogen, Schistosoma japonicum and showed that the diploid state, and its associated heterozygous advantage, significantly affects the outcome of attack by the immune system and the accumulation of antigenic diversity in the parasite population. We demonstrate here that diploidy provides a novel means of immune evasion for diploid pathogens. PMID:22468230

  18. Meetings on Plasmodium vivax and Schistosoma japonicum in Asia.

    PubMed

    1999-10-01

    Manila hosted two meetings on malaria and schistosomiasis for Asian scientists in June 1999. Efforts in developing a vaccine for Plasmodium vivax, precursor of 40-50% of malaria in Latin America and Asia, were emphasized: 1) the need for greater understanding of the epidemiology of the vivax malaria, development of immunity, and interactions between the two main species of plasmodium; 2) the role of primate models of vivax malaria; 3) unique biological questions posed by P. vivax; and 4) the large production of existing vivax candidate vaccines for clinical trials. Moreover, the Philippines and China continue to be affected by Schistosoma japonicum despite extensive control efforts and availability of praziquantel. Diversity of opinion over the expected vaccine was discussed. Technical expertise in the production of vaccines has improved while links between researchers and vaccine manufacturers need to be improved.

  19. [Cloning, expression and phylogenetic analysis of Schistosoma japonicum calcyphosine gene].

    PubMed

    Ju, Chuan; Peng, Jian-xin; Xu, Bin; Wang, Wei; Feng, Zheng; Hu, Wei

    2006-10-01

    To clone and express Schistosoma japonicum (Sj) calcyphosine gene, and purify the expressed protein. The encoding sequence selected from Sj cDNA library was amplified by PCR. After subcloned into prokaryotic expression vector pET-28a, the expressed protein was purified with His -Tag affinity chromatography. Western blotting was used to detect the immunogenicity. The structure and functions of the protein were analyzed by bioinformatics method, and the phylogenetic tree of the protein was drawn. The recombinant protein was specifically recognized by the Sj infected rabbit serum. The bioinformatics analysis showed 4 EF-hand domains. Besides, it was predicted that Sj calcyphosine contains two phosphorylation sites for protein kinase C, eight phosphorylation sites for casein kinase II and one N-myristoylation site. The Sj calcyphosine belonged to type-II calcyphosine. The calcyphosine gene is a calcium-binding protein and might be a potential candidate for diagnosis, vaccine or drug target.

  20. High Prevalence of Schistosoma japonicum Infection in Carabao from Samar Province, the Philippines: Implications for Transmission and Control

    PubMed Central

    Gordon, Catherine A.; Acosta, Luz P.; Gray, Darren J.; Olveda, Remigo M.; Jarilla, Blanca; Gobert, Geoffrey N.; Ross, Allen G.; McManus, Donald P.

    2012-01-01

    Schistosoma japonicum is endemic in the Philippines, China and Indonesia, and infects more than 40 mammalian host species, all of which can act as reservoirs of infection. In China, water buffaloes have been shown to be major reservoirs of human infection. However, in the Philippines, carabao have not been considered important reservoir hosts for S. japonicum due to the low prevalence and infection intensities reported, the only exception being a qPCR-based study indicating 51% of carabao were S. japonicum-positive. However, the low prevalence found for the same animals when using conventional copro-parasitological techniques means that there is still confusion about the role of carabao in the transmission of schistosomiasis japonicum. To address this inconsistency, and to shed light on the potential role of carabao in the transmission of S. japonicum in the Philippines, we undertook a pilot survey, collecting fecal samples from animals in Western Samar Province and we used a combination of molecular and copro-parasitological techniques to determine the prevalence and intensity of S. japonicum. We found a high prevalence of S. japonicum in the carabao using a validated real-time PCR (qPCR) and a copro-parasitological tool, the formalin-ethyl acetate sedimentation (FEA-SD) technique. A much lower prevalence of S. japonicum was recorded for the same fecal samples using conventional PCR, the Kato-Katz technique and miracidial hatching. These results suggest that, due to their low diagnostic sensitivity, traditional copro-parasitological techniques underestimate infection in carabao. The use of FEA-SD and qPCR provides a more accurate diagnosis. Based on these findings, the role of bovines in the transmission of S. japonicum appears to be more important in the Philippines than previously recognized, and this may have significant implications for the future control of schistosomiasis there, particularly as, in contrast with previous surveys, we found an unprecedented

  1. Assessment of morbidity due to Schistosoma japonicum infection in China

    PubMed Central

    2014-01-01

    This paper presents a historical assessment of morbidity due to the Schistosoma japonicum infection in China. Due to the socio-economic situation, which did not allow for a control program to be implemented until the early 1950s, morbidity was serious and mortality was high before this. Based on a few investigations and published papers, it can be said that the disease caused millions of deaths, and destroyed numerous families and villages. Since the 1950s, there has been a national control program, intensive control and prevention work has been carried out, and consequently the disease is being controlled. At present, both the prevalence and the morbidity of the disease have been decreasing substantially. The morbidity of the three phases of the disease is outlined in this paper. Comparatively higher morbidity is seen in the acute and advanced phases of the disease. The four major forms of advanced schistosomiasis i.e., ascites, megalosplenia, dwarfism, and colonic tumoroid proliferation, are outlined with their characteristic clinical presentations; their proportions are different during various periods of the national control program. Ectopic schistosomiasis and the relationship between the S. japonicum infection and colorectal cancer are also discussed. Post-transmission schistosomiasis is briefly discussed (which can happen even if the disease reaches the criteria of elimination, and the infection and transmission have stopped, but yet it still develops). The problem of mammalian reservoir hosts of S. japonicum makes the epidemiology and control of schistosomiasis in China even more complicated and arduous, and the control progress in animal reservoirs is briefly presented. PMID:24529186

  2. Development of chiral praziquantel analogues as potential drug candidates with activity to juvenile Schistosoma japonicum.

    PubMed

    Zheng, Yang; Dong, LanLan; Hu, Changyan; Zhao, Bo; Yang, Chunhua; Xia, Chaoming; Sun, Dequn

    2014-09-01

    A series of chiral praziquantel analogues were synthesized and evaluated against Schistosoma japonicum both in vitro and in vivo. All compounds exhibited low to considerable good activity in vivo. Remarkably, worm reduction rate of R-3 was 60.0% at a single oral dose of 200mg/kg against juvenile stage of Schistosoma japonicum. The target compounds displayed in vivo antischistosomal activity against both Schistosoma japonicum and Schistosoma mansoni. Furthermore, all R-isomers displayed stronger antischistosomal activity than S-isomers in vivo, indicating R-isomers were the active enantiomers, while S-isomers were less active ones. This structure activity relationship (SAR) could have important implications in further drug development for schistosomiasis.

  3. Nested-PCR assay for detection of Schistosoma japonicum infection in domestic animals.

    PubMed

    Zhang, Xin; He, Chuan-Chuan; Liu, Jin-Ming; Li, Hao; Lu, Ke; Fu, Zhi-Qiang; Zhu, Chuan-Gang; Liu, Yi-Ping; Tong, Lai-Bao; Zhou, De-Bao; Zha, Li; Hong, Yang; Jin, Ya-Mei; Lin, Jiao-Jiao

    2017-04-13

    Schistosomiasis japonica is a common zoonosis. Domestic animals are the primary source of infection and play an important role in disease transmission. The prevalence and infectivity of this disease in domestic animals in China have significantly decreased and, for this reason, diagnostics with a higher sensitivity have become increasingly necessary. It was reported that polymerase chain reaction (PCR)-based methods could be used to detect schistosome infection in humans and animals and presented a high sensitivity and specificity. The present study aimed to develop a PCR-based method for detection of Schistosoma japonicum infection in domestic animals. A specific nested-PCR assay was developed to detect S. japonicum infection in domestic animals via amplification of a 231-bp DNA fragment of retrotransposon SjR2. The developed assay was first used in sera and dry blood filter paper (DBFP) from goats and buffaloes at different time points of infection. Then, 78 DBFPs from 39 artificially-infected bovines at 14 and 28 days post-infection and 42 DBFPs from schistosome-negative bovines from the city of Huangshan in the Anhui province were used to evaluate the diagnostic validity. Furthermore, this assay was used to detect S. japonicum infection in domestic animals in Dongzhi and Wangjiang counties. The expected PCR product was detected in eggs and adult worms of S. japonicum and blood samples from S. japonicum-infected goats and water buffaloes, but not from Fasciola and Haemonchus contortus worms. The nested-PCR assay could detect the target S. japonicum DNA in DBFPs from goats and buffaloes after day 3 post-infection. The sensitivity in buffaloes at 14 and 28 days post-infection was 92.30% (36/39) and 100% (39/39), respectively. The specificity was 97.60% (41/42). The positivity rates in Dongzhi and Wangjiang counties were 6.00% and 8.00% in bovines and 22.00% and 16.67% in goats, respectively. The positivity rates in goats in both counties were higher than those

  4. Cloning and Characterisation of Schistosoma japonicum Insulin Receptors

    PubMed Central

    You, Hong; Zhang, Wenbao; Jones, Malcolm K.; Gobert, Geoffrey N.; Mulvenna, Jason; Rees, Glynn; Spanevello, Mark; Blair, David; Duke, Mary; Brehm, Klaus; McManus, Donald P.

    2010-01-01

    Background Schistosomes depend for growth and development on host hormonal signals, which may include the insulin signalling pathway. We cloned and assessed the function of two insulin receptors from Schistosoma japonicum in order to shed light on their role in schistosome biology. Methodology/Principal Findings We isolated, from S. japonicum, insulin receptors 1 (SjIR-1) and 2 (SjIR-2) sharing close sequence identity to their S. mansoni homologues (SmIR-1 and SmIR-2). SjIR-1 is located on the tegument basal membrane and the internal epithelium of adult worms, whereas SjIR-2 is located in the parenchyma of males and the vitelline tissue of females. Phylogenetic analysis showed that SjIR-2 and SmIR-2 are close to Echinococcus multilocularis insulin receptor (EmIR), suggesting that SjIR-2, SmIR-2 and EmIR share similar roles in growth and development in the three taxa. Structure homology modelling recovered the conserved structure between the SjIRs and Homo sapiens IR (HIR) implying a common predicted binding mechanism in the ligand domain and the same downstream signal transduction processing in the tyrosine kinase domain as in HIR. Two-hybrid analysis was used to confirm that the ligand domains of SjIR-1 and SjIR-2 contain the insulin binding site. Incubation of adult worms in vitro, both with a specific insulin receptor inhibitor and anti-SjIRs antibodies, resulted in a significant decrease in worm glucose levels, suggesting again the same function for SjIRs in regulating glucose uptake as described for mammalian cells. Conclusions Adult worms of S. japonicum possess insulin receptors that can specifically bind to insulin, indicating that the parasite can utilize host insulin for development and growth by sharing the same pathway as mammalian cells in regulating glucose uptake. A complete understanding of the role of SjIRs in the biology of S. japonicum may result in their use as new targets for drug and vaccine development against schistosomiasis. PMID:20352052

  5. High prevalence of Schistosoma japonicum and Fasciola gigantica in bovines from Northern Samar, the Philippines.

    PubMed

    Gordon, Catherine A; Acosta, Luz P; Gobert, Geoffrey N; Jiz, Mario; Olveda, Remigio M; Ross, Allen G; Gray, Darren J; Williams, Gail M; Harn, Donald; Li, Yuesheng; McManus, Donald P

    2015-02-01

    The cause of zoonotic schistosomiasis in the Philippines is Schistosoma japonicum, which infects up to 46 mammalian hosts, including humans and bovines. In China, water buffaloes have been identified as major reservoir hosts for schistosomiasis japonica, contributing up to 75% of human transmission. In the Philippines, water buffaloes (carabao; Bubalus bubalis carabanesis) have, historically, been considered unimportant reservoirs. We therefore revisited the possible role of bovines in schistosome transmission in the Philippines, using the recently described formalin-ethyl acetate sedimentation (FEA-SD) technique and a qPCR assay to examine fecal samples from 153 bovines (both carabao and cattle) from six barangays in Northern Samar. A high prevalence of S. japonicum was found using qPCR and FEA-SD in both cattle (87.50% and 77.08%, respectively) and carabao (80.00% and 55.24%, respectively). The average daily egg output for each bovine was calculated at 195,000. High prevalence and infection intensity of F. gigantica was also found in the bovines by qPCR and FEA-SD (95.33% and 96.00%, respectively). The identification of bovines as major reservoir hosts for S. japonicum transmission suggests that bovine treatment and/or vaccination, as one becomes available, should be included in any future control program that aims to reduce the disease burden due to schistosomiasis in the Philippines.

  6. High Prevalence of Schistosoma japonicum and Fasciola gigantica in Bovines from Northern Samar, the Philippines

    PubMed Central

    Gordon, Catherine A.; Acosta, Luz P.; Gobert, Geoffrey N.; Jiz, Mario; Olveda, Remigio M.; Ross, Allen G.; Gray, Darren J.; Williams, Gail M.; Harn, Donald; Li, Yuesheng; McManus, Donald P.

    2015-01-01

    The cause of zoonotic schistosomiasis in the Philippines is Schistosoma japonicum, which infects up to 46 mammalian hosts, including humans and bovines. In China, water buffaloes have been identified as major reservoir hosts for schistosomiasis japonica, contributing up to 75% of human transmission. In the Philippines, water buffaloes (carabao; Bubalus bubalis carabanesis) have, historically, been considered unimportant reservoirs. We therefore revisited the possible role of bovines in schistosome transmission in the Philippines, using the recently described formalin-ethyl acetate sedimentation (FEA-SD) technique and a qPCR assay to examine fecal samples from 153 bovines (both carabao and cattle) from six barangays in Northern Samar. A high prevalence of S. japonicum was found using qPCR and FEA-SD in both cattle (87.50% and 77.08%, respectively) and carabao (80.00% and 55.24%, respectively). The average daily egg output for each bovine was calculated at 195,000. High prevalence and infection intensity of F. gigantica was also found in the bovines by qPCR and FEA-SD (95.33% and 96.00%, respectively). The identification of bovines as major reservoir hosts for S. japonicum transmission suggests that bovine treatment and/or vaccination, as one becomes available, should be included in any future control program that aims to reduce the disease burden due to schistosomiasis in the Philippines. PMID:25643317

  7. Taurine drinking ameliorates hepatic granuloma and fibrosis in mice infected with Schistosoma japonicum.

    PubMed

    Yu, Yan-Rong; Ni, Xian-Qiang; Huang, Jie; Zhu, Yong-Hong; Qi, Yong-Fen

    2016-04-01

    In schistosomiasis, egg-induced hepatic granuloma formation is a cytokine-mediated, predominantly CD4(+) Th2 immune response that can give rise to hepatic fibrosis. Hepatic fibrosis is the main cause of increased morbidity and mortality in humans with schistosome infection. Taurine has various physiological functions and hepatoprotective properties as well as anti-inflammatory and immunomodulatory activity. However, little is known about the role of taurine in schistosome egg-induced granuloma formation and fibrosis. We aimed to evaluate the therapeutic potential of taurine as preventative treatment for Schistosoma japonicum infection. Mice infected with S. japonicum cercariae were supplied with taurine drinking water (1% w/v) for 4 weeks starting at 4 weeks post-infection. Taurine supplementation significantly improved the liver pathologic findings, reduced the serum levels of aminotransferases and area of hepatic granuloma, and prevented fibrosis progression. In addition, taurine decreased the expression of the granulomatous and fibrogenic mediators transforming growth factor β1, tumor necrosis factor α, monocyte chemotactic protein 1α and macrophage inflammatory protein 1α as well as the endoplasmic reticulum stress marker glucose-regulated protein 78. Thus, taurine can significantly attenuate S. japonicum egg-induced hepatic granuloma and fibrosis, which may depend in part on the downregulation of some relevant cytokine/chemokines and reducing the endoplasmic reticulum stress response.

  8. Taurine drinking ameliorates hepatic granuloma and fibrosis in mice infected with Schistosoma japonicum

    PubMed Central

    Yu, Yan-Rong; Ni, Xian-Qiang; Huang, Jie; Zhu, Yong-Hong; Qi, Yong-Fen

    2016-01-01

    In schistosomiasis, egg-induced hepatic granuloma formation is a cytokine-mediated, predominantly CD4+ Th2 immune response that can give rise to hepatic fibrosis. Hepatic fibrosis is the main cause of increased morbidity and mortality in humans with schistosome infection. Taurine has various physiological functions and hepatoprotective properties as well as anti-inflammatory and immunomodulatory activity. However, little is known about the role of taurine in schistosome egg-induced granuloma formation and fibrosis. We aimed to evaluate the therapeutic potential of taurine as preventative treatment for Schistosoma japonicum infection. Mice infected with S. japonicum cercariae were supplied with taurine drinking water (1% w/v) for 4 weeks starting at 4 weeks post-infection. Taurine supplementation significantly improved the liver pathologic findings, reduced the serum levels of aminotransferases and area of hepatic granuloma, and prevented fibrosis progression. In addition, taurine decreased the expression of the granulomatous and fibrogenic mediators transforming growth factor β1, tumor necrosis factor α, monocyte chemotactic protein 1α and macrophage inflammatory protein 1α as well as the endoplasmic reticulum stress marker glucose-regulated protein 78. Thus, taurine can significantly attenuate S. japonicum egg-induced hepatic granuloma and fibrosis, which may depend in part on the downregulation of some relevant cytokine/chemokines and reducing the endoplasmic reticulum stress response. PMID:27054062

  9. The identification, expression profile, and preliminary characterization of Tsunagi protein from Schistosoma japonicum.

    PubMed

    Liu, Miao; Wang, Xiaonan; Lei, Li; Zhao, Zhirong; Shen, Jijia

    2010-08-01

    Tsunagi is an evolutionarily conserved protein, which is required for germ line differentiation during the development of Drosophila melanogaster and Caenorhabditis elegans. In this paper, we describe a homologue of the Tsunagi protein from Schistosoma japonicum (SjTsunagi). The gene for this protein was isolated from S. japonicum using degenerate and anchored polymerase chain reaction (PCR), and the deduced protein has sequence homology and similarity to Tsunagi protein of other species, including C. elegans, D. melanogaster, Xenopus laevis, Mus musculus, and human. Amino acid sequence analysis showed the presence of a conserved RNA recognition motif. The predicted protein encoded by SjTsunagi gene is 177 amino acids in length with an estimated molecular mass of 20 kD. Immunoblot and reverse transcription-PCR analysis confirms SjTsunagi protein is expressed in eggs, cercariae, schistosomula, and adult female and adult male parasites. Pull-down and co-immunoprecipitation assay confirms that protein of SjTsunagi can interact with SjMago nashi in vitro. Taken together, this is the first report of the expression and preliminary characterization analysis of the SjTsunagi gene from S. japonicum.

  10. Identification of Host Insulin Binding Sites on Schistosoma japonicum Insulin Receptors.

    PubMed

    Stephenson, Rachel J; Toth, Istvan; Liang, Jiening; Mangat, Amanjot; McManus, Donald P; You, Hong

    2016-01-01

    Schistosoma japonicum insulin receptors (SjIRs) have been identified as encouraging vaccine candidates. Interrupting or blocking the binding between host insulin and the schistosome insulin receptors (IRs) may result in reduced glucose uptake leading to starvation and stunting of worms with a reduction in egg output. To further understand how schistosomes are able to exploit host insulin for development and growth, and whether these parasites and their mammalian hosts compete for the same insulin source, we identified insulin binding sites on the SjIRs. Based on sequence analysis and the predicted antigenic structure of the primary sequences of the SjIRs, we designed nine and eleven peptide analogues from SjIR-1 and SjIR-2, respectively. Using the Octet RED system, we identified analogues derived from SjIR-1 (10) and SjIR-2 (20, 21 and 22) with insulin-binding sequences specific for S. japonicum. Nevertheless, the human insulin receptor (HIR) may compete with the SjIRs in binding human insulin in other positions which are important for HIR binding to insulin. However, no binding occurred between insulin and parasite analogues derived from SjIR-1 (2, 7 and 8) and SjIR-2 (14, 16 and 18) at the same locations as HIR sequences which have been shown to have strong insulin binding affinities. Importantly, we found two analogues (1 and 3), derived from SjIR-1, and two analogues (13 and 15) derived from SjIR-2, were responsible for the major insulin binding affinity in S. japonicum. These peptide analogues were shown to have more than 10 times (in KD value) stronger binding capacity for human insulin compared with peptides derived from the HIR in the same sequence positions. Paradoxically, analogues 1, 3, 13 and 15 do not appear to contain major antigenic determinants which resulted in poor antibody responses to native S. japonicum protein. This argues against their future development as peptide-vaccine candidates.

  11. Factors influencing the transmission of Schistosoma japonicum in the mountains of Sichuan Province of China.

    PubMed

    Spear, Robert C; Seto, Edmund; Liang, Song; Birkner, Merrill; Hubbard, Alan; Qiu, Dongchuan; Yang, Changhong; Zhong, Bo; Xu, Fashen; Gu, Xueguang; Davis, George M

    2004-01-01

    Twenty villages in the Anning River Valley of southwestern Sichuan China were surveyed for Schistosoma japonicum infections in humans and domestic animals. Also surveyed were human water contact patterns, snail populations, cercarial risk in irrigation systems, and agricultural land use. Few animals were infected, while village prevalence of infection in humans ranged from 3% to 68% and average village eggs per gram of stool ranged from 0 to 110. Except for occupation and education, individual characteristics were not strong determinants of infection intensity within a village. Differences in human infection intensity between these villages are strongly associated with crop type, with low-intensity villages principally growing rice, in contrast to villages devoting more land to vegetables and tobacco. Cercarial risk in village irrigation systems is associated with snail density and human infection intensity through the use of manure-based fertilizer. Some of the agricultural and environmental factors associated with infection risk can be quantified using remote sensing technology.

  12. Studies on Schistosoma japonicum infection in the Philippines*

    PubMed Central

    Pesigan, T. P.; Hairston, N. G.; Jauregui, J. J.; Garcia, E. G.; Santos, A. T.; Santos, B. C.; Besa, A. A.

    1958-01-01

    This study of the molluscan host (Oncomelania quadrasi) of bilharziasis in the Philippines is divided into two parts, the first dealing with the biology of the host and the second with the interrelationship between the host and Schistosoma japonicum. In the first part, the snail's distribution and habitat are considered in some detail, and then field and laboratory studies on its behaviour and activity are reported on. A section on the life history of O. quadrasi covers its growth, reproduction, egg-laying and survival. This is followed by a study of the population dynamics of the snail. In the second part, the laboratory procedures used for infecting snails and for obtaining cercariae are described, and the finding that more female than male snails are seen infected is discussed. A section is devoted to the effect of infection on the reproduction, growth and longevity of the snail, and an account is given of cercarial output, of the distribution of cercariae in a snail colony and of their presence downstream from snail colonies. The final section deals with natural fluctuations in snail infection rates, which appear to show a cycle related to rainfall. ImagesFIG. 27FIG. 35 PMID:13536804

  13. Repeated Schistosoma japonicum Infection Following Treatment in Two Cohorts: Evidence for Host Susceptibility to Helminthiasis?

    PubMed Central

    Carlton, Elizabeth J.; Hubbard, Alan; Wang, Shuo; Spear, Robert C.

    2013-01-01

    Background In light of multinational efforts to reduce helminthiasis, we evaluated whether there exist high-risk subpopulations for helminth infection. Such individuals are not only at risk of morbidity, but may be important parasite reservoirs and appropriate targets for disease control interventions. Methods/Principal Findings We followed two longitudinal cohorts in Sichuan, China to determine whether there exist persistent human reservoirs for the water-borne helminth, Schistosoma japonicum, in areas where treatment is ongoing. Participants were tested for S. japonicum infection at enrollment and two follow-up points. All infections were promptly treated with praziquantel. We estimated the ratio of the observed to expected proportion of the population with two consecutive infections at follow-up. The expected proportion was estimated using a prevalence-based model and, as highly exposed individuals may be most likely to be repeatedly infected, a second model that accounted for exposure using a data adaptive, machine learning algorithm. Using the prevalence-based model, there were 1.5 and 5.8 times more individuals with two consecutive infections than expected in cohorts 1 and 2, respectively (p<0.001 in both cohorts). When we accounted for exposure, the ratio was 1.3 (p = 0.013) and 2.1 (p<0.001) in cohorts 1 and 2, respectively. Conclusions/Significance We found clustering of infections within a limited number of hosts that was not fully explained by host exposure. This suggests some hosts may be particularly susceptible to S. japonicum infection, or that uncured infections persist despite treatment. We propose an explanatory model that suggests that as cercarial exposure declines, so too does the size of the vulnerable subpopulation. In low-prevalence settings, interventions targeting individuals with a history of S. japonicum infection may efficiently advance disease control efforts. PMID:23505589

  14. Surveillance of Schistosoma japonicum Infection in Domestic Ruminants in the Dongting Lake Region, Hunan Province, China

    PubMed Central

    Liu, Jinming; Zhu, Chunxia; Shi, Yaojun; Li, Hao; Wang, Lanpin; Qin, Shangtian; Kang, Saie; Huang, Yanpin; Jin, Yamei; Lin, Jiaojiao

    2012-01-01

    Background Schistosomiasis japonica is prevalent in Asian countries and it remains a major public health problem in China. The major endemic foci are the marsh and lake regions of southern China, particularly the Dongting Lake region bordering Hunan and Hubei provinces, and the Poyang Lake region in Jiangxi province. Domestic ruminants, especially bovines, have long been considered to play a major role in the transmission of Schistosoma japonicum to humans. Methods and Findings A miracidial hatching technique was used to investigate the prevalence of S. japonicum infections in domestic ruminants and field feces collected from two towns located to the south and east of Dongting Lake, Hunan province, between 2005 and 2010. The overall prevalence of infection was not significantly reduced from 4.93% in 2005 to 3.64% in 2008, after which it was maintained at this level. Bovines comprised 23.5–58.2% of the total infected ruminants, while goats comprised 41.8–76.5%. Infection rates in cattle and goats were significantly higher than those found in buffalo in most study years. The prevalence in buffalo younger than three years was significantly higher than that in those aged over three years. All the positive field samples of feces were derived from bovines in Nandashan. In Matang Town, 61.22% of the positive field feces were from bovines, while the rest were from goats. The positive rates for field feces were approximately the same in April and November/October. Conclusions The present study found that bovines and goats are major sources of S. japonicum infection in the Dongting lake region and there was age-related resistance in buffalo. Both bovines and goats should be treated equally when controlling S. japonicum infections in the Dongting lake region. It is essential to conduct an additional mass treatment in late March or early April, in addition to the original treatment scheme. PMID:22359638

  15. Comparative Phylogenetic Studies on Schistosoma japonicum and Its Snail Intermediate Host Oncomelania hupensis: Origins, Dispersal and Coevolution.

    PubMed

    Attwood, Stephen W; Ibaraki, Motomu; Saitoh, Yasuhide; Nihei, Naoko; Janies, Daniel A

    2015-01-01

    Schistosoma japonicum causes major public health problems in China and the Philippines; this parasite, which is transmitted by freshwater snails of the species Oncomelania hupensis, causes the disease intestinal schistosomiasis in humans and cattle. Researchers working on Schistosoma in Africa have described the relationship between the parasites and their snail intermediate hosts as coevolved or even as an evolutionary arms race. In the present study this hypothesis of coevolution is evaluated for S. japonicum and O. hupensis. The origins and radiation of the snails and the parasite across China, and the taxonomic validity of the sub-species of O. hupensis, are also assessed. The findings provide no evidence for coevolution between S. japonicum and O. hupensis, and the phylogeographical analysis suggests a heterochronous radiation of the parasites and snails in response to different palaeogeographical and climatic triggers. The results are consistent with a hypothesis of East to West colonisation of China by Oncomelania with a re-invasion of Japan by O. hupensis from China. The Taiwan population of S. japonicum appears to be recently established in comparison with mainland Chinese populations. The snail and parasite populations of the western mountain region of China (Yunnan and Sichuan) appear to have been isolated from Southeast Asian populations since the Pleistocene; this has implications for road and rail links being constructed in the region, which will breach biogeographical barriers between China and Southeast Asia. The results also have implications for the spread of S. japonicum. In the absence of coevolution, the parasite may more readily colonise new snail populations to which it is not locally adapted, or even new intermediate host species; this can facilitate its dispersal into new areas. Additional work is required to assess further the risk of spread of S. japonicum.

  16. Comparative Phylogenetic Studies on Schistosoma japonicum and Its Snail Intermediate Host Oncomelania hupensis: Origins, Dispersal and Coevolution

    PubMed Central

    Attwood, Stephen W.; Ibaraki, Motomu; Saitoh, Yasuhide; Nihei, Naoko; Janies, Daniel A.

    2015-01-01

    Background Schistosoma japonicum causes major public health problems in China and the Philippines; this parasite, which is transmitted by freshwater snails of the species Oncomelania hupensis, causes the disease intestinal schistosomiasis in humans and cattle. Researchers working on Schistosoma in Africa have described the relationship between the parasites and their snail intermediate hosts as coevolved or even as an evolutionary arms race. In the present study this hypothesis of coevolution is evaluated for S. japonicum and O. hupensis. The origins and radiation of the snails and the parasite across China, and the taxonomic validity of the sub-species of O. hupensis, are also assessed. Methodology/Principal Findings The findings provide no evidence for coevolution between S. japonicum and O. hupensis, and the phylogeographical analysis suggests a heterochronous radiation of the parasites and snails in response to different palaeogeographical and climatic triggers. The results are consistent with a hypothesis of East to West colonisation of China by Oncomelania with a re-invasion of Japan by O. hupensis from China. The Taiwan population of S. japonicum appears to be recently established in comparison with mainland Chinese populations. Conclusions/Significance The snail and parasite populations of the western mountain region of China (Yunnan and Sichuan) appear to have been isolated from Southeast Asian populations since the Pleistocene; this has implications for road and rail links being constructed in the region, which will breach biogeographical barriers between China and Southeast Asia. The results also have implications for the spread of S. japonicum. In the absence of coevolution, the parasite may more readily colonise new snail populations to which it is not locally adapted, or even new intermediate host species; this can facilitate its dispersal into new areas. Additional work is required to assess further the risk of spread of S. japonicum. PMID:26230619

  17. Praziquantel derivatives exhibit activity against both juvenile and adult Schistosoma japonicum.

    PubMed

    Duan, Wen-wen; Qiu, Si-jie; Zhao, Yue; Sun, Huan; Qiao, Chunhua; Xia, Chao-ming

    2012-02-15

    A praziquantel analog 10-hydroxy praziquantel and eight praziquantel/peroxide conjugates were synthesized. The biological activity of these compounds was evaluated against juvenile and adult stages of Schistosoma japonicum. Unlike praziquantel, 10-hydroxy praziquantel exhibits activity against both juvenile and adult Schistosoma japonicumin. All hybrid compounds displayed modest to significant worm killing activity. The present study has important significance for the development of hybrid antischistosomal drugs.

  18. Development of larval Schistosoma japonicum blocked in Oncomelania hupensis by pre-infection with larval Exorchis sp.

    PubMed

    Tang, Chong-Ti; Lu, Ming-Ke; Guo, Yue; Wang, Yi-Nan; Peng, Jin-Yong; Wu, Wei-Bao; Li, Wen-Hong; Weimer, Bart C; Chen, Dong

    2009-12-01

    Schistosomiasis continues to be a significant public health threat in the world. In the area of parasitic diseases, it is widely considered second only to malaria as a global health problem, with an incalculable drain on the economic resources of countries where it is endemic. Schistosoma japonicum is widespread in eastern and southeastern Asia, where the amphibious snail, Oncomelania hupensis, is the intermediate host. In the present study, we found that infection of O. hupensis with the mature eggs of another trematode, Exorchis sp., inhibited development of S. japonicum mother sporocysts in O. hupensis. Exorchis sp. commonly infects the edible fish Parasilurus asotus in China, but it is harmless to humans. This discovery provides an opportunity for possible biological control of S. japonicum infection and transmission. Additionally, it has the potential to substantially reduce the impact of the global S. japonicum that is independent of antihelminthic use. The mechanisms used by Exorchis sp. to inhibit infection by S. japonicum in the snail require further investigation.

  19. Efficacy of artemether and artesunate in mice infected with praziquantel non-susceptible isolate of Schistosoma japonicum.

    PubMed

    Wang, Wei; Li, Tian-Yu; Ji, Yuan; Qu, Guo-Li; Qian, Yi-Li; Li, Hong-Jun; Dai, Jian-Rong; Liang, You-Sheng

    2014-03-01

    Praziquantel is currently the only drug of choice for the treatment of human Schistosoma japonicum infections, and praziquantel-based chemotherapy has been proved to be generally effective to control the morbidity and reduce the prevalence and intensity of S. japonicum infections. However, the potential emergence of praziquantel resistance in S. japonicum seriously threatens the elimination of this neglected tropical disease in China. The purpose of this study was designed, in mouse animals, to evaluate the in vivo efficacy of artemether and artesunate against praziquantel non-susceptible S. japonicum. Mice infected with a praziquantel non-susceptible isolate and a praziquantel-susceptible isolate of S. japonicum were treated with artemether and artesunate at a single oral dose of 300 mg/kg given once on each of days 7-8 and 35-36 post-infection to assess the efficacy against juvenile and adult worms. Administration with artemether and artesunate at a single oral dose of 300 mg/kg on each of days 7-8 post-infection resulted in total worm burden reductions of 72.8 and 73.5% in mice infected with praziquantel-susceptible S. japonicum, and 77.9 and 74.1% in mice infected with the non-susceptible isolate (both P values >0.05), while the same treatments given on days 35-36 post-infection reduced total worm burdens by 71.4 and 69.6% in mice infected with the susceptible isolate, and 75.3 and 69.6% in mice infected with the non-susceptible parasite (both P values >0.05). It is concluded that there is no evidence for reduced susceptibility of artemether and artesunate in praziquantel non-susceptible S. japonicum.

  20. Studies on Schistosoma japonicum infection in the Philippines*

    PubMed Central

    Pesigan, T. P.; Farooq, M.; Hairston, N. G.; Jauregui, J. J.; Garcia, E. G.; Santos, A. T.; Santos, B. C.; Besa, A. A.

    1958-01-01

    The geographical location and physical features of the island of Leyte in the Philippines, where bilharziasis is endemic and where the studies reported here were conducted, are described in the first part of this paper. An account is also given of the climate, soils, vegetation, population and rural structure, and public health of the island. The second part opens with a brief historical review of bilharziasis japonica in the Philippines up to 1953, when a control project was started. The objectives of this project, the areas selected, the census data and sampling used, and the techniques adopted are described. There follows a discussion of the prevalence of bilharziasis and its relationship to age, sex, occupation and environment; the prevalence of other common helminthic infections is also considered. In a section on the natural history and public health significance of bilharziasis, an approach to quantitative assessment of disease and disability and a method for evaluating the economic burden of bilharziasis are suggested. The incidence of disease in children of 5-9 years is reviewed in the same section. An analysis is made of possible strain differences of S. japonicum in Leyte, and the relative role of human and other animal hosts is assessed. The last section deals with the egg-laying habits of S. japonicum. ImagesFIG. 9FIG. 13FIG. 15FIG. 28 PMID:13536797

  1. Spatial and temporal transcriptomics of Schistosoma japonicum-induced hepatic granuloma formation reveals novel roles for neutrophils.

    PubMed

    Chuah, Candy; Jones, Malcolm K; Burke, Melissa L; Owen, Helen C; Anthony, Barrie J; McManus, Donald P; Ramm, Grant A; Gobert, Geoffrey N

    2013-08-01

    The severity of schistosome egg-induced hepatic granulomatous pathology depends markedly on the nature of the host immune responses. In this study, we used LMM and microarray analysis to compare gene expression profiles of histologically distinct zones within, and directly proximal to, hepatic granulomas that developed in C57BL/6 mice infected with Schistosoma japonicum. There was significant up-regulation of type-1, type-2, and type-17 immune-associated genes within the granuloma core (adjacent to eggs), followed by increased expression of type-2 and fibrotic genes at the outer zones of granulomas. Neutrophil-associated genes were also found to be expressed differentially in the core and at the peripheral zone of granulomas, present at 7 weeks p.i., demonstrating a significant role of neutrophils in S. japonicum granulomatous pathology. The release of NETs was observed microscopically in granulomas obtained from the livers of infected mice and when human neutrophils were incubated in vitro in the presence of S. japonicum eggs. These finding are the first to suggest a novel, dual role for neutrophils in the mediation of tissue damage and repair in S. japonicum egg-induced hepatic granulomatous lesions. Together, these results provide an overview of the local events occurring within the granuloma microenvironment.

  2. An effective sequence characterized amplified region-PCR method derived from restriction site-amplified polymorphism for the identification of female Schistosoma japonicum of zoonotic significance.

    PubMed

    Zhao, Guang-Hui; Li, Juan; Lin, Rui-Qing; Zou, Feng-Cai; Liu, Wei; Yuan, Zi-Guo; Mo, Xi-Hao; Song, Hui-Qun; Weng, Ya-Biao; Zhu, Xing-Quan

    2010-01-01

    In the present study, restriction site-amplified polymorphism (RSAP) markers were used to examine the genetic variability of Schistosoma japonicum isolates from different endemic provinces in mainland China. Of the 45 pairs of primers screened, 10 RSAP markers showed a clear banding pattern with good resolution; however, only six exhibited a polymorphism among different isolates. Among six RSAP markers, one pair of primers (R8+R10) was able to differentiate male and female parasites, and amplified one constant specific band for female S. japonicum isolates. The specific band was recovered, re-amplified and sequenced, and a sequence of 162 bp was obtained. Based on this sequence, a pair of specific primers was designed and used to develop sequence characterized amplified region (SCAR)-PCR assay for identification and differentiation of female S. japonicum isolates. The SCAR-PCR assay allowed the specific identification of female S. japonicum, with no amplicons being amplified from male S. japonicum, Fasciola hepatica, Clonorchis sinensis, S. mansoni (male and female parasite). DNA sequencing confirmed the identity of the amplified products. The minimum amount of DNA detectable using SCAR-PCR assay was 0.3 ng for female S. japonicum. The SCAR-PCR was able to differentiate effectively the male and female S. japonicum worms collected from 12 geographical origins in eight endemic provinces, the gender of which was known based on the morphological and biological features. These results showed that SCAR-PCR provides an effective tool for the sex differentiation studies of S. japonicum, identification of female S. japonicum, diagnosis and epidemiological survey of S. japonicum infections in animals and human.

  3. Schistosoma japonicum and S. mansoni cercariae: different effects of protein in medium, of mechanical stress, and of an intact complement system on in vitro transformation to schistosomula.

    PubMed

    Wang, Wenshi; Kirschfink, Michael; Ruppel, Andreas

    2006-08-01

    The cercariae of Schistosoma japonicum were subjected in vitro to treatments known for Schistosoma mansoni to generate schistosomula-like organisms. As a technical prerequisite to pipette or to otherwise handle the sticky cercariae of S. japonicum, the addition of protein to water or medium was found to abolish the stickiness of cercariae of this species. Shearing forces exerted in vitro by syringe (22 G) passage are known since long to fully transform S. mansoni cercariae, but this treatment was found to be much less efficient with S. japonicum. Thus, even with very narrow needles (27 G), complete transformation of cercariae was not obtained with S. japonicum. Complement, provided by fresh human serum, is also well known to induce rapid transformation of S. mansoni cercariae with subsequent killing of the schistosomula. This treatment of S. japonicum cercariae induced degeneration of the tails and strongly promoted the transformation to schistosomula-like organisms, but at a much slower pace. These effects were absent from sera either heat-inactivated or depleted of factor B or of complement component C8, but were restored after adding the purified respective complement components. The schistosomula-like organisms of S. japonicum were not susceptible to lysis after 1 day of in vitro culture in the presence of 50% fresh human serum, although both cercariae and schistosomula of S. mansoni were killed under these conditions. In conclusion, the dynamics of in vitro transformation of S. japonicum cercariae differ significantly from those of S. mansoni, and complement has a major transformation-promoting activity.

  4. A potential screening factor for accumulation of cholesteyl ester transfer protein deficiency in East Asia: Schistosoma japonicum.

    PubMed

    Yokoyama, Shinji

    2014-04-04

    Cholesteryl ester transfer protein (CETP)-deficiency manifests a unique plasma lipoprotein profile without other apparent symptoms. It is highly common in East Asia while rather rare anywhere else. A potential environmental screening factor(s) may therefore contribute to this eccentric distribution, such as its selective advantage against a regional illness, most likely an infectious disease, in relation to plasma lipoproteins. Blood flukes use the host plasma lipoproteins as nutrient sources through the lipoprotein receptor-like systems. Its Asian-specific species, Schistosoma (S) japonicum, which has been endemic in East Asia, takes up cholesteryl ester (CE) from high-density lipoprotein (HDL) for the embryonation of their eggs to miracidia, a critical step of the hepatic pathogenesis of this parasite, but poorly from HDL of CETP-deficiency. CD36-related protein (CD36RP) was cloned from the adults and the eggs of S. japonicum, with 1880-bp encoding 506 amino-acid residues exhibiting the CD36 domains and two transmembrane regions. Its extracellular domain selectively bound human HDL but neither LDL nor CETP-deficiency HDL, and the antibody against the extracellular domain suppressed the selective HDL-CE uptake and embryonation of the eggs. When infected with S. japonicum, wild-type mice developed less hepatic granulomatosis than CETP-transgenic mice by the ectopic egg embryonation. CD36RP is thus a candidate receptor of S. japonicum to facilitate uptake of HDL-CE necessary for egg embryonation. Abnormal HDL caused by CETP-deficiency retards this process and thereby protects the patients from development of hepatic lesions. S. japonicum infection is a potential screening factor for high prevalence of CETP deficiency in East Asia. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. The characteristics of NK cells in Schistosoma japonicum-infected mouse spleens.

    PubMed

    Li, Lu; Cha, Hefei; Yu, Xiuxue; Xie, Hongyan; Wu, Changyou; Dong, Nuo; Huang, Jun

    2015-12-01

    Natural killer (NK) cells are classic innate immune cells that play roles in many types of infectious disease. Recently, some new characteristics of NK cells were discovered. In this study, C57BL/6 mice were infected with Schistosoma japonicum for 5-6 weeks and lymphocytes were isolated from the spleen to detect some of the NK cell characteristics by multiparametric flow cytometry. The results revealed that the S. japonicum infection induced a large amount of NK cells, although the percentage of NK cells was not increased significantly. At the same time, the results showed that infected mouse splenic NK cells expressed increased levels of CD25 and CD69 and produced more IL-2, IL-4, and IL-17 and less IFN-γ after stimulation with PMA and ionomycin. This meant that NK cells played a role in S. japonicum infection. Moreover, decreased NKG2A/C/E (CD94) expression levels were detected on the surface of NK cells from infected mouse spleens, which might serve as a NK cell activation mechanism. Additionally, high levels of IL-10, but not PD-1, were expressed on the infected mouse NK cells, which implied that functional exhaustion might exist in the splenic NK cells from S. japonicum-infected mice. Collectively, our results suggest that NK cells play important roles in the course of S. japonicum infection.

  6. Preliminary characterization and expression of Vasa-like gene in Schistosoma japonicum.

    PubMed

    Diao, Yujie; Hua, Mengqing; Shao, Yanjing; Huang, Wei; Liu, Miao; Ren, Cuiping; Ji, Yongsheng; Chen, Jianmin; Shen, Jijia

    2015-07-01

    The Vasa gene is a vital germline marker to study the origin and development of germ cells and gonads in many organisms. Until now, little information was available about the characteristics of the Vasa gene in Schistosoma japonicum (S. japonicum). In this study, we cloned the open reading frame (ORF) of the S. japonicum Vasa-like gene (Sj-Vasa). The expression pattern and tissue localization of Sj-Vasa were also analyzed. Our results showed that Sj-Vasa shared the general feature of DEAD-box family member proteins. Sj-Vasa was transcribed and expressed throughout the S. japonicum life cycle with transcription exhibiting high levels at day 24 in both male and female worms, and the expression level in the female was always higher than that in the male. Sj-Vasa protein was localized in a variety of tissues of adult schistosomes, including the gonads (ovary, vitellarium, and testes), the subtegument, and some cells of the parenchyma. To our knowledge, this is the first report of preliminary characterization and expression of the Vasa-like gene that may play an important role in the development of the worm, especially in reproductive organs of S. japonicum.

  7. Recombinant T2 RNase protein of Schistosoma japonicum inhibits expression of α-SMA in LX-2 cells.

    PubMed

    Wang, Jianxin; Peng, Wenxia; Feng, Jinrong; Zhu, Dandan; Chen, Jinling; Sun, Xiaolei; Lyu, Lei; Ju, Shaoqing; Duan, Yinong

    2016-10-01

    Recombinant T2 RNase glycoprotein, which showed a certain degree of homology to Omega-1 from Schistosoma mansoni eggs, was expressed in adult worms of Schistosoma japonicum, but not in eggs of S. japonicum. The direct biological role of the recombinant T2 RNase protein in activation of hepatic stellate cells (HSCs) remains unknown. In the present study, the immortalized human HSC line (LX-2 cells) was treated with the recombinant T2 RNase protein at indicated concentrations for various time points in vitro. The expression levels of α-smooth muscle actin (α-SMA) and Smad4 were detected by Western blot. The results showed that the recombinant T2 RNase protein significantly diminished the expression levels of α-SMA and Smad4 in LX-2 cells. The upregulated expression levels of α-SMA and Smad4 by TGF-β1 in LX-2 cells were both suppressed by the recombinant T2 RNase protein. These data suggest that the recombinant T2 RNase protein may be a potential target of therapeutic strategy for the treatment of hepatic fibrosis.

  8. Suppression of the Insulin Receptors in Adult Schistosoma japonicum Impacts on Parasite Growth and Development: Further Evidence of Vaccine Potential

    PubMed Central

    You, Hong; Gobert, Geoffrey N.; Cai, Pengfei; Mou, Rong; Nawaratna, Sujeevi; Fang, Guofu; Villinger, Francois; McManus, Donald P.

    2015-01-01

    To further investigate the importance of insulin signaling in the growth, development, sexual maturation and egg production of adult schistosomes, we have focused attention on the insulin receptors (SjIRs) of Schistosoma japonicum, which we have previously cloned and partially characterised. We now show, by Biolayer Interferometry, that human insulin can bind the L1 subdomain (insulin binding domain) of recombinant (r)SjIR1 and rSjIR2 (designated SjLD1 and SjLD2) produced using the Drosophila S2 protein expression system. We have then used RNA interference (RNAi) to knock down the expression of the SjIRs in adult S. japonicum in vitro and show that, in addition to their reduced transcription, the transcript levels of other important downstream genes within the insulin pathway, associated with glucose metabolism and schistosome fecundity, were also impacted substantially. Further, a significant decrease in glucose uptake was observed in the SjIR-knockdown worms compared with luciferase controls. In vaccine/challenge experiments, we found that rSjLD1 and rSjLD2 depressed female growth, intestinal granuloma density and faecal egg production in S. japonicum in mice presented with a low dose challenge infection. These data re-emphasize the potential of the SjIRs as veterinary transmission blocking vaccine candidates against zoonotic schistosomiasis japonica in China and the Philippines. PMID:25961574

  9. Suppression of the Insulin Receptors in Adult Schistosoma japonicum Impacts on Parasite Growth and Development: Further Evidence of Vaccine Potential.

    PubMed

    You, Hong; Gobert, Geoffrey N; Cai, Pengfei; Mou, Rong; Nawaratna, Sujeevi; Fang, Guofu; Villinger, Francois; McManus, Donald P

    2015-05-01

    To further investigate the importance of insulin signaling in the growth, development, sexual maturation and egg production of adult schistosomes, we have focused attention on the insulin receptors (SjIRs) of Schistosoma japonicum, which we have previously cloned and partially characterised. We now show, by Biolayer Interferometry, that human insulin can bind the L1 subdomain (insulin binding domain) of recombinant (r)SjIR1 and rSjIR2 (designated SjLD1 and SjLD2) produced using the Drosophila S2 protein expression system. We have then used RNA interference (RNAi) to knock down the expression of the SjIRs in adult S. japonicum in vitro and show that, in addition to their reduced transcription, the transcript levels of other important downstream genes within the insulin pathway, associated with glucose metabolism and schistosome fecundity, were also impacted substantially. Further, a significant decrease in glucose uptake was observed in the SjIR-knockdown worms compared with luciferase controls. In vaccine/challenge experiments, we found that rSjLD1 and rSjLD2 depressed female growth, intestinal granuloma density and faecal egg production in S. japonicum in mice presented with a low dose challenge infection. These data re-emphasize the potential of the SjIRs as veterinary transmission blocking vaccine candidates against zoonotic schistosomiasis japonica in China and the Philippines.

  10. Chronic Schistosoma japonicum Infection Reduces Immune Response to Vaccine against Hepatitis B in Mice

    PubMed Central

    Chen, Lin; Liu, Wen-qi; Lei, Jia-hui; Guan, Fei; Li, Man-jun; Song, Wen-jian; Li, Yong-long; Wang, Ting

    2012-01-01

    Background Hepatitis B and schistosomiasis are most prevalent in Africa and Asia, and co-infections of both are frequent in these areas. The immunomodulation reported to be induced by schistosome infections might restrict immune control of hepatitis B virus (HBV) leading to more severe viral infection. Vaccination is the most effective measure to control and prevent HBV infection, but there is evidence for a reduced immune response to the vaccine in patients with chronic schistosomiasis japonica. Methodology/Principal Findings In this paper, we demonstrate in a mouse model that a chronic Schistosoma japonicum infection can inhibit the immune response to hepatitis B vaccine (HBV vaccine) and lead to lower production of anti-HBs antibodies, interferon-γ (IFN-γ) and interleukin-2 (IL-2). After deworming with Praziquantel (PZQ), the level of anti-HBs antibodies gradually increased and the Th2-biased profile slowly tapered. At 16 weeks after deworming, the levels of anti-HBs antibodies and Th1/Th2 cytokines returned to the normal levels. Conclusions/Significance The results suggest that the preexisting Th2-dominated immune profile in the host infected with the parasite may down–regulate levels of anti-HBs antibodies and Th1 cytokines. To improve the efficacy of HBV vaccination in schistosome infected humans it may be valuable to treat them with praziquantel (PZQ) some time prior to HBV vaccination. PMID:23272112

  11. [In vitro effect of photoactivated hypericin on anti-Schistosoma japonicum adult male worms].

    PubMed

    Cai, Ru; She, Xin-Ping; Wang, Yu; Gong, Wei; Zhang, Hui-Qin; Xia, Chao-Ming

    2014-06-01

    To investigate the in vitro effect of photoactivated hypericin on anti-Schistosoma japonicum adult male worms. Kunming mice were infected with 60-80 Schistosoma japonicum single-sex cercariae. At 6 weeks post-infection, the mice were sacrificed and adult male worms of S. japonicum were collected. The worms were incubated in DMEM medium containing different concentrations of hypericin (0.1, 0.2, 0.5, 1.0, 1.5, 2.0, and 2.5 micromol/L) in the presence or absence of light. In photoactivated hypericin groups, after 6 h of dark incubation the worms were exposed to LED light irradiation (590 nm) for 30, 60, 90, and 120 min, respectively, and then cultured overnight in darkness (16h). In the next morning, the parasites were washed, resuspended in drug-free medium, and incubated in the dark for 48 h. These worms were observed with stereomicroscopy and scanning electron microscopy (SEM). Photoactivated hypericin showed the ability to kill Schistosoma japonicum in vitro. The death rate was 20% in 0.1 micromol/L photoactivated hypericin group under 30 min irradiation, and 100% in 2 micromol/L under 90 min irradiation and 2.5 micromol/L under 60 min irradiation, respectively. In blank control group, DMSO control group, and hypericin groups without light irradiation, worms were alive. After 60 min irradiation, the worms in 1.0, 2.5, 5.0 micromol/L photoactivated hypericin groups showed spastic paralysis characterized by reduced body length, pronounced tight curl, body stiffness, and complete cessation of movement. Surface tegumental damages of adult worms in 2.0 micromol/L photoactivated hypericin group for 60 min irradiation were observed under SEM, such as vacuole formation, erosion and peeling of the tegument, collapse of the sensory papillae, and even the normal structure disappeared completely. Both death rate and morphological damage of the worms treated by photoactivated hypericin were positively correlated with hypericin dose and light irradiation time. Photoactivated

  12. New Perspectives on Host-Parasite Interplay by Comparative Transcriptomic and Proteomic Analyses of Schistosoma japonicum

    PubMed Central

    Wang, Sheng-Yue; Cui, Shu-Jian; Chi, Ming; Yan, Qing; Wang, Xin-Rong; Song, Huai-Dong; Xu, Xue-Nian; Wang, Ju-Jun; Zhang, Xiang-Lin; Zhang, Xin; Wang, Zhi-Qin; Xue, Chun-Liang; Brindley, Paul J; McManus, Donald P; Yang, Peng-Yuan; Feng, Zheng; Chen, Zhu; Han, Ze-Guang

    2006-01-01

    Schistosomiasis remains a serious public health problem with an estimated 200 million people infected in 76 countries. Here we isolated ~ 8,400 potential protein-encoding cDNA contigs from Schistosoma japonicum after sequencing circa 84,000 expressed sequence tags. In tandem, we undertook a high-throughput proteomics approach to characterize the protein expression profiles of a number of developmental stages (cercariae, hepatic schistosomula, female and male adults, eggs, and miracidia) and tissues at the host-parasite interface (eggshell and tegument) by interrogating the protein database deduced from the contigs. Comparative analysis of these transcriptomic and proteomic data, the latter including 3,260 proteins with putative identities, revealed differential expression of genes among the various developmental stages and sexes of S. japonicum and localization of putative secretory and membrane antigens, enzymes, and other gene products on the adult tegument and eggshell, many of which displayed genetic polymorphisms. Numerous S. japonicum genes exhibited high levels of identity with those of their mammalian hosts, whereas many others appeared to be conserved only across the genus Schistosoma or Phylum Platyhelminthes. These findings are expected to provide new insights into the pathophysiology of schistosomiasis and for the development of improved interventions for disease control and will facilitate a more fundamental understanding of schistosome biology, evolution, and the host-parasite interplay. PMID:16617374

  13. Synthesis, Bioactivity Evaluation, and Toxicity Assessment of Novel Salicylanilide Ester Derivatives as Cercaricides against Schistosoma japonicum and Molluscicides against Oncomelania hupensis

    PubMed Central

    Wang, Weisi; Qin, Zhiqiang; Zhu, Dan; Wei, Yufen; Li, Shizhu

    2015-01-01

    A series of novel salicylanilide ester derivatives were synthesized, characterized, and evaluated for cercaricidal potential against Schistosoma japonicum and molluscicidal potential against Oncomelania hupensis. Four derivatives exhibited remarkable cercaricidal activity superior to that of niclosamide. Among them, the most active compound, 4-chloro-2-((2-methoxy-4-nitrophenyl)carbamoyl)phenyl 4-methoxybenzoate (compound 4c), showed a marked minimum effective cercaricidal concentration as low as 0.43 μM and significant molluscicidal activity, with a 50% lethal concentration (LC50) of 0.206 g/m2. Particularly, compound 4c displayed 88-fold decreased fish toxicity on Danio rerio and 44-fold reduced cytotoxicity on human kidney HEK293 cells in comparison with the toxicity of niclosamide. The results indicated that 4c could serve as a promising drug candidate, with environmental safety properties, against Schistosoma japonicum at transmission stages. The preliminary molecular mechanism of target compounds in Schistosoma japonicum cercariae was also investigated. Salicylanilide ester derivatives exhibited an inhibitory effect on nitric oxide synthase (NOS) but no effect on lactate dehydrogenase (LDH) and acetylcholinesterase (AChE), and a strong and significant correlation between NOS inhibitory efficacy and cercaricidal activity was observed. In addition, 4c could downregulate the expression of NOS in a dose-dependent manner. These results suggested that NOS was probably one of the drug targets of salicylanilide esters. PMID:26503661

  14. Screening and identification of DNA aptamers toward Schistosoma japonicum eggs via SELEX

    PubMed Central

    Long, Yuqian; Qin, Zhiqiang; Duan, Minlan; Li, Shizhu; Wu, Xiaoqiu; Lin, Wei; Li, Jianglin; Zhao, Zilong; Liu, Jing; Xiong, Dehui; Huang, Yi; Hu, Xiaoxiao; Yang, Chao; Ye, Mao; Tan, Weihong

    2016-01-01

    Schistosomiasis is a major parasitic disease caused by blood flukes of the genus Schistosoma. Several million people all over the world are estimated to suffer from severe morbidity as a consequence of schistosomiasis. The worm’s eggs, which cause the symptoms of schistosomiasis, are generally used to diagnose the disease. In this study, we employed egg-based systematic evolution of ligands by exponential enrichment (egg-SELEX) and identified a panel of ssDNA aptamers specifically binding to eggs derived from S. japonicum. Among these, two aptamers LC6 and LC15 exhibited strong binding to and specific recognition of S. japonicum eggs, but not eggs from Fasciolopsis buski, Enterobius, Ascaris or Clonorchis sinensis. Furthermore, tissue imaging results revealed that LC15 could recognize S. japonicum eggs laid in liver tissues with a detection ratio of 80.5%. Collectively, therefore, we obtained useful aptamers specifically recognizing S. japonicum eggs, which will facilitate the development of an effective tool for both schistosomiasis diagnosis and drug delivery. PMID:27121794

  15. Schistosoma japonicum: An ultraviolet-attenuated cercarial vaccine applicable in the field for water buffaloes

    SciTech Connect

    Shi, Y.E.; Jiang, C.F.; Han, J.J.; Li, Y.L.; Ruppel, A. )

    1990-07-01

    Water buffaloes were vaccinated three times with 10,000 Schistosoma japonicum cercariae irradiated with ultraviolet (uv) light at a dose of 400 microW x min/cm2. The irradiation was performed with cheap, simple, and portable equipment in a rural area of Hubei Province (People's Republic of China). A challenge infection of 1000 untreated cercariae was given to six vaccinated and six naive control buffaloes, while two vaccinated animals were not challenged. The experiment was terminated 6 weeks after the challenge. Control animals had lost body weight and harbored a mean of 110 worms and 37 eggs per gram of liver. The vaccinated animals gained weight after the challenge and developed 89% resistance to infection with S. japonicum. Since schistosomiasis japonica is nowadays transmitted in China predominantly by domestic livestock, a uv-attenuated cercarial vaccine for bovines may contribute to the control of this disease.

  16. Immunoproteomics Identification of Major IgE and IgG4 Reactive Schistosoma japonicum Adult Worm Antigens Using Chronically Infected Human Plasma

    PubMed Central

    Boamah, Daniel; Kikuchi, Mihoko; Huy, Nguyen Tien; Okamoto, Kenta; Chen, Honggen; Ayi, Irene; Boakye, Daniel Adjei; Bosompem, Kwabena Mante; Hirayama, Kenji

    2012-01-01

    Immunoepidemiological studies from endemic areas have revealed age-dependent resistance correlation with increased level of IgE and decreased level of IgG4 antibodies in responses to schistosomes’ soluble worm antigen. However, there have been limited studies on analyses of major antigens that provoke IgE and IgG4 immune response during chronic stage of schistosomiasis. In this study, for the first time, immunoproteomics approach has been applied to identify S. japonicum worm antigens in liquid fractions that are recognized by IgE and IgG4 antibody using plasma from chronically infected population. ProteomeLabPF 2D fractionated 1-D and 2-D fractions of SWA antigens were screened using pooled high IgE/IgG4 reactive plasma samples by dot-blot technique. In 1-D fractions, IgE isotype was detected by fewer antigenic fractions (43.2%). The most recognized isotype was IgG3 (79.5%) followed by IgG1 (75.0%) and IgG4 (61.4%). Liquid chromatography MS/MS protein sequencing of reactive 2-D fractions revealed 18 proteins that were identified, characterized and gene ontology categories determined. 2-D fractions containing proteins such as zinc finger, RanBP2-type, domain-containing protein were strongly recognized by IgE and moderately by IgG4 whereas fractions containing proteins such as ubiquitin-conjugating enzyme and cytosolic II 5'-nucleotidase strongly recognizing by IgG subclasses (IgG1, IgG3 and IgG4) but not IgE. By this study, a simple and reproducible proteomic method has been established to identify major immunoreactive S. japonicum antigens. It is anticipated that this will stimulate further research on the immunogenicity and protective potential of proteins identified as well as discovery of novel compounds that have therapeutic importance. PMID:23264728

  17. In vivo and in vitro activity of oil extract of garlic (Allium sativum Linnaeus) against Schistosoma japonicum cercariae.

    PubMed

    Wan, Kang; Wang, Peng; Zhang, Leibo

    2017-01-01

    The activity of garlic oil extract against Schistosoma japonicum cercariae was evaluated. The in vitro and in vivo cercaricidal activities against S. japonicum larvae were determined. Exposure to ≥ 10-6 (v/v) garlic emulsions for 30 min led to 100% cercariae mortality; pre-exposure treatment with ≥ 10-4 (v/v) garlic emulsions showed 100% preventive efficacy against S. japonicum infection, while pre-treatment with 10-5 and 10-6 (v/v) emulsions achieved 20%-40% preventive efficacy and 35.2%-63.6% worm burden reduction. Garlic oil extract has activity against S. japonicum larvae and a promising preventive efficacy against S. japonicum infection.

  18. Induction of resistance in Oncomelania hupensis nosophora against Schistosoma japonicum, but not against Paragonimus ohirai, using irradiated miracidia.

    PubMed

    Hata, H; Kojima, S

    1989-11-01

    Oncomelania hupensis nosophora snails sensitized with X-irradiated Schistosoma japonicum miracidia demonstrated resistance against a following challenge infection with non-irradiated homologous miracidia. The resistance in O. h. nosophora against S. japonicum was acquired within 1 day of sensitization, and it was strongest in a group challenged at an interval of 3 days. The resistance persisted for at least 4 weeks. Histological examinations revealed amoebocyte accumulation around the challenged S. japonicum sporocysts. On the other hand, when O. h. nosophora sensitized by exposure to X-irradiated P. ohirai or S. japonicum miracidia were subsequently challenged with normal P. ohirai miracidia, no resistance was observed, although they expressed the resistance against heterologous S. japonicum infection.

  19. Differential pulmonic NK and NKT cell responses in Schistosoma japonicum-infected mice.

    PubMed

    Cha, Hefei; Qin, Wenjuan; Yang, Quan; Xie, Hongyan; Qu, Jiale; Wang, Mei; Chen, Daixiong; Wang, Fang; Dong, Nuo; Chen, Longhua; Huang, Jun

    2017-02-01

    Natural killer cells (NK cells) and natural killer T cells (NKT cells) play a role in anti-infection, anti-tumor, transplantation immunity, and autoimmune regulation. However, the role of NK and NKT cells during Schistosoma japonicum (S. japonicum) infection has not been widely reported, especially regarding lung infections. The aim of this study was to research the NK and NKT cell response to S. japonicum infection in the lungs of mice. Using immunofluorescent histological analysis, NK and NKT cells were found near pulmonary granulomas. Moreover, flow cytometry revealed that the percentage and number of pulmonic NK cells in S. japonicum-infected mice were significantly increased (P < 0.05). However, the percentage and cell number of NKT cells were decreased compared to those of normal mice (P < 0.05). The expression of CD69 on pulmonic NK and NKT cells was increased after infection (P < 0.05), and CD25 expression increased only on NKT cells (P < 0.05). Intracellular cytokine staining showed a higher percentage of IFN-γ(+) and lower percentage of IL-5(+) pulmonic NK cells (P < 0.05) compared to controls. However, the percentage of IL-17(+), IL-10(+), and IL-5(+) pulmonic NKT cells significantly increased (P < 0.05). Additionally, there was a significant decrease in NKG2A/C/E (CD94) expression and an increase of NKG2D (CD314) expression on pulmonic NKT cells (P < 0.05), which might serve as a mechanism for NKT cell activation during S. japonicum infection.

  20. Studies on Schistosoma japonicum infection in the Philippines*

    PubMed Central

    Pesigan, T. P.; Farooq, M.; Hairston, N. G.; Jauregui, J. J.; Garcia, E. G.; Santos, A. T.; Santos, B. C.; Besa, A. A.

    1958-01-01

    Among the measures used in attempts to control the snail host of S. japonicum in Leyte Province, Philippines, where the terrain is unsuited to the application of molluscicides, have been removal of vegetation in and around infested streams, drainage of water-logged areas, filling low-lying areas with earth or flooding them, and digging fishponds in sluggish streams. Each of these measures is described in detail. Experiments carried out in rice-fields, which harbour great numbers of snails, have shown that improvements in rice-growing methods will not only markedly reduce the snail population but also double the rice yield. A campaign to promote the use of pit latrines encountered the serious difficulty that such latrines were not acceptable to the people. However, there is evidence that use of pit latrines does bring about a reduction in snail infection rates. No single control measure is recommended for all snail habitats, the choice of method depending on local circumstances; in many areas a combination of methods proved advantageous. It is felt that mass treatment of infected persons would not be fully effective until transmission is more thoroughly under control. PMID:13585073

  1. Comparative Study of Transcriptome Profiles of Mouse Livers and Skins Infected by Fork-Tailed or Non-Fork-Tailed Schistosoma japonicum.

    PubMed

    Yang, Yan; He, Jun-Jun; Hu, Shuang; Chang, Hua; Xiang, Xun; Yang, Jian-Fa; Zou, Feng-Cai

    2017-01-01

    Schistosoma japonicum (S. japonicum) is a worldwide spread pathogen which penetrates host skin and then induces several diseases in infected host, such as fibrosis, formation of granulomas, hepatocirrhosis, and hepatomegaly. In present study, for the first time, transcriptomic profiles of mouse livers and skins infected by fork-tailed S. japonicum cercaria or non-fork-tailed S. japonicum cercaria were analyzed by using RNA-seq. The present findings demonstrated that transcriptomic landscapes of livers and skins infected by fork-tailed S. japonicum cercaria or non-fork-tailed S. japonicum cercaria were different. S. japonicum has great influence on hepatic metabolic processes. Fork-tailed S. japonicum cercaria upregulated hepatic metabolic processes, while non-fork-tailed S. japonicum cercaria downregulated hepatic metabolic processes. For the metabolism process or the metabolism enzyme expressional change, the pharmacokinetics of host could be changed during S. japonicum infection, regardless the biotypes of S. japonicum cercariae. The changes of infected skins focused on upregulation of immune response. During the S. japonicum skin infection period, fork-tailed S. japonicum cercaria infection induced stronger immune response comparing with that immune response triggered by non-fork-tailed S. japonicum cercaria. The transcription factor enrichment analysis showed that Irf7, Stat1 and Stat2 could play important roles in gene regulation during fork-tailed S. japonicum cercaria infection.

  2. Schistosoma japonicum migration through mouse skin compared histologically and immunologically with S. mansoni.

    PubMed

    Wang, Lin; Li, Yong-Long; Fishelson, Zvi; Kusel, John R; Ruppel, Andreas

    2005-02-01

    The migration of Schistosoma japonicum and S. mansoni through mouse skin epidermis and dermis was compared by immunofluorescence techniques from 4 to 22 h after infection. At all times, the percentage of parasites detected in the dermis was significantly higher for S. japonicum than for S. mansoni. Thus, S. japonicum migrates more rapidly very early after infection. This agrees with the quicker migration observed previously by this species for later times. Both species expressed antigens related to the cercarial glycocalyx on the parasite body and antigenically detectable elastase in the acetabular glands, at least until 22 h after infection. Bot sets of antigens were also left as "traces" in cercarial migration channels in the skin as well as in skin tissue in the absence of detectable worms or migration channels. The data further substantiate differences between schistosome species in the speed of migration, and suggest that glycocalyx-related antigens and cercarial elastase continue to be expressed for at least 1 day after infection.

  3. Gender-associated gene expression in two related strains of Schistosoma japonicum.

    PubMed

    Fitzpatrick, Jennifer M; Johansen, Maria Vang; Johnston, David A; Dunne, David W; Hoffmann, Karl F

    2004-08-01

    Host inflammatory responses directed against eggs laid by sexually-mature Schistosoma japonicum female worms instigate lesion formation and associated clinical pathologies during infection. To identify parasite gene transcripts that associate with egg production and to characterise sexually-mature adult gene expression profiles of two related Chinese strains, S. japonicum cDNA microarrays were fabricated using 457 ESTs originating from three parasite developmental stages. Twenty-two female-associated and 8 male-associated gene transcripts were identified in the adult Anhui strain whereas 21 female-associated and 7 male-associated gene transcripts were revealed in the adult Zhejiang strain. RT-PCR analysis, in situ enzyme localisation studies and enzymatic assays confirmed the cDNA microarray results, and importantly, provided information previously unappreciated in schistosome conjugal biology. Specifically, our novel findings include the female-specific expression of genes putatively involved in haemoglobin digestion and eggshell formation including extracellular superoxide dismutase, two histidine-rich proteins, a large blood-brain barrier amino acid transporter and two tyrosinase orthologues. In contrast, transcripts involved in mechanical support (actin), cytoskeletal infrastructure (e.g. dynein light chain 3 and myosin regulatory light chain) and tegumental biology (e.g. TM4SF and Sj25) were more highly represented in adult male schistosomes. Together these data establish a transcriptional basis for adult schistosome labour division and expands the list of novel S. japonicum gender-associated gene transcripts that may be considered targets for improved intervention strategies.

  4. Real-time PCR demonstrates high prevalence of Schistosoma japonicum in the Philippines: implications for surveillance and control.

    PubMed

    Gordon, Catherine A; Acosta, Luz P; Gobert, Geoffrey N; Olveda, Remigio M; Ross, Allen G; Williams, Gail M; Gray, Darren J; Harn, Donald; Li, Yuesheng; McManus, Donald P

    2015-01-01

    The Philippines has a population of approximately 103 million people, of which 6.7 million live in schistosomiasis-endemic areas with 1.8 million people being at risk of infection with Schistosoma japonicum. Although the country-wide prevalence of schistosomiasis japonica in the Philippines is relatively low, the prevalence of schistosomiasis can be high, approaching 65% in some endemic areas. Of the currently available microscopy-based diagnostic techniques for detecting schistosome infections in the Philippines and elsewhere, most exhibit varying diagnostic performances, with the Kato-Katz (KK) method having particularly poor sensitivity for detecting low intensity infections. This suggests that the actual prevalence of schistosomiasis japonica may be much higher than previous reports have indicated. Six barangay (villages) were selected to determine the prevalence of S. japonicum in humans in the municipality of Palapag, Northern Samar. Fecal samples were collected from 560 humans and examined by the KK method and a validated real-time PCR (qPCR) assay. A high S. japonicum prevalence (90.2%) was revealed using qPCR whereas the KK method indicated a lower prevalence (22.9%). The geometric mean eggs per gram (GMEPG) determined by the qPCR was 36.5 and 11.5 by the KK. These results, particularly those obtained by the qPCR, indicate that the prevalence of schistosomiasis in this region of the Philippines is much higher than historically reported. Despite being more expensive, qPCR can complement the KK procedure, particularly for surveillance and monitoring of areas where extensive schistosomiasis control has led to low prevalence and intensity infections and where schistosomiasis elimination is on the horizon, as for example in southern China.

  5. Seasonal dynamics of Schistosoma japonicum infection in buffaloes in the Poyang Lake region and suggestions on local treatment schemes.

    PubMed

    Liu, Jin-Ming; Yu, Hua; Shi, Yao-Jun; Li, Hao; He, Liang; Li, Jian-Xi; Dong, Chang-Hua; Xie, Qiao; Jin, Ya-Mei; Lu, Ke; Lin, Jiao-Jiao

    2013-11-15

    Schistosomiasis japonica remains a major public health problem and the Poyang Lake region in Jiangxi province is one of the worst affected endemic areas. Buffaloes play a major role in the transmission of Schistosoma japonicum to humans. The aim of the present study was to increase understanding of the epidemic characteristics of schistosomiasis japonica in water buffaloes in the Poyang Lake region, after achieving the national mid-term goal, and to provide a basis for further interventions. The baseline prevalence in two villages in the Poyang Lake region in May 2010 was compared with respect to usage, sex and age in the total study population. Seasonal dynamics from May 2010 to May 2011 were observed in a natural village in the studied area. The baseline prevalence of infection in both villages (Caohui and Gaozhou) was 4.94% in May 2010. The prevalence in buffalo younger than 12 months was 12.82% in Caohui and 15.11% in Gaozhou, which was significantly higher than that found in those aged 13-24 months and older than 24 months. Of the 28 infected buffaloes, 82.14% (23) were younger than 12 months. The flow of seasonal dynamics showed that S. japonicum infection buffaloes were found from May to July and from November to January of the following year. This survey suggested that it is necessary to conduct two mass treatments (especially for young animals) in late March or early April and November, with an additional treatment of positive animals in July or June.

  6. Characteristics of IL-17 induction by Schistosoma japonicum infection in C57BL/6 mouse liver

    PubMed Central

    Chen, Dianhui; Luo, Xueping; Xie, Hongyan; Gao, Zhiyan; Fang, Huilong; Huang, Jun

    2013-01-01

    Schistosomiasis japonica is a severe tropical disease caused by the parasitic worm Schistosoma japonicum. Among the most serious pathological effects of S. japonicum infection are hepatic lesions (cirrhosis and fibrosis) and portal hypertension. Interleukin-17 (IL-17) is a pro-inflammatory cytokine involved in the pathogenesis of many inflammatory and infectious conditions, including schistosomiasis. We infected C57BL/6 mice with S. japonicum and isolated lymphocytes from the liver to identify cell subsets with high IL-17 expression and release using flow cytometry and ELISA. Expression and release of IL-17 was significantly higher in hepatic lymphocytes from infected mice compared with control mice in response to both non-specific stimulation with anti-CD3 monoclonal antibody plus/anti-CD28 monoclonal antibody and PMA plus ionomycin. We then compared IL-17 expression in three hepatic T-cell subsets, T helper, natural killer T and γδT cells, to determine the major source of IL-17 during infection. Interleukin-17 was induced in all three subsets by PMA + ionomycin, but γδT lymphocytes exhibited the largest increase in expression. We then established a mouse model to further investigate the role of IL-17 in granulomatous and fibrosing inflammation against parasite eggs. Reducing IL-17 activity using anti-IL-17A antibodies decreased infiltration of inflammatory cells and collagen deposition in the livers of infected C57BL/6 mice. The serum levels of soluble egg antigen (IL) -specific IgGs were enhanced by anti-IL-17A monoclonal antibody blockade, suggesting that IL-17 normally serves to suppress this humoral response. These findings suggest that γδT cells are the most IL-17-producing cells and that IL-17 contributes to granulomatous inflammatory and fibrosing reactions in S. japonicum-infected C57BL/6 mouse liver. PMID:23551262

  7. [The in silico elongation and analysis of the EST from Schistosoma japonicum].

    PubMed

    Liu, Han-teng; Wu, Zhong-dao; Zou, Sai-de; Shao, Xiao

    2004-08-01

    To construct a platform for in silico elongation and batch analysis of Schistosoma japonicum (Sj) ESTs, acquire the potential novel genes and research the expression profile of the genes. On the basis of Linux operating system and local ESTs database of Sj, the BLAST and PHRAP softwares were used to construct a program to achieve the elongation of ESTs. Stand-alone BLAST search against the nr database helped analyze the elongated sequence. After finishing the batch analysis script, the platform was used to research the Sj gene expression profile and acquire the potential novel genes. The platform showed satisfactory efficiency and fidelity. 487 elongated sequences obtained from 552 and 307 elongated sequences showed high homology within the nr database downloaded from NCBI. Furthermore, 104 elongated sequences displayed significant homology but showed no homology before elongated. 27 potential novel genes were filtered out. An effective platform for Sj ESTs data mining was accomplished and further information on the potential novel genes was acquired.

  8. Synthesis of fluorescent derivatives of praziquantel: cell-imaging and interaction with Schistosoma japonicum cercariae.

    PubMed

    Xie, Yunzhi; Li, Yibao; Wu, Yongquan; Liu, Chunhua; Li, Xiaokang; Li, Xun; Fan, Xiaolin

    2013-09-28

    Schistosomiasis is one of the most burdensome of the neglected tropical diseases. Praziquantel is a recommended drug for treatment against all forms of schistosomiasis. To investigate the interaction between praziquantel and Schistosoma japonicum cercariae, two praziquantel derivatives (PZQ-2 and PZQ-3) and one praziquantel fluorescent derivative (PZQ-5) have been synthesized and characterized using nuclear magnetic resonance spectroscopy (NMR) and MS spectra. The cytotoxicity of PZQ-2, PZQ-3 and PZQ-5 was measured by performing the methyl thiazolyl tetrazolium (MTT) assay. The cell viability for them shows that the three compounds exhibit low cytotoxicity to HeLa cells. Cell imaging experiments demonstrate that PZQ-5 is biocompatible and cell-permeable, which indicates that PZQ-5 is suitable for studying their interaction. Confocal fluorescence microscopy revealed that PZQ-5 is mainly located at the cercarial tegument, which leads to the death of cercariae with the increase in time.

  9. [Biological identification on sub-cultivation cells of Schistosoma japonicum adult worms in vitro].

    PubMed

    Liu, Wei; Zeng, Tie-bing; Zeng, Qing-ren; Cai, Chun; Zhang, Zu-ping; Gong, Yan-fei; Cai, Li-ting; Zhang, Shun-ke; Xu, Xi-ping

    2006-10-01

    Cultivation of cells from 30-day old Schistosoma japonicum (S.j) adult worms showed that the growth features of the cells were semi-floating and accumulative. The survival rate of the primary cells, passage cells prior to the 5th generation and recovered cells was all up to 90%. Phases of cell division were observed during cultivation. Chromosome karyotype of the 5th generation cells possessed diploid feature of the blood-flukes (2n=8 in number). Ultrastructure of the 5th generation cells showed that four types of cells in normal morphology and three types of cells in abnormal morphology were both viewed. It is suggested that some of the cells from S.j adult worms were subcultured successfuly in the 1640-40 defined medium.

  10. Field evaluation of a recombinase polymerase amplification assay for the diagnosis of Schistosoma japonicum infection in Hunan province of China.

    PubMed

    Xing, Weiwei; Yu, Xinling; Feng, Jingtao; Sun, Kui; Fu, Wenliang; Wang, Yuanyuan; Zou, Minji; Xia, Wenrong; Luo, Zhihong; He, Hongbin; Li, Yuesheng; Xu, Donggang

    2017-02-21

    Current diagnostic methods for Schistosoma japonicum infection are insensitive for low-density infections. Therefore, a new diagnostic assay based on recombinase polymerase amplification (RPA) technology was established and assessed for field applification. The S.japonicum RPA assay was developed to target highly repetitive retrotransposon SjR2 gene of S japonicum, and its sensitivity and specificity were assessed by serial dilution of S. japonicum genomic DNA and other related worm genomic DNA respectively. The RPA diagnostic validity was first evaluated in 60 fecal samples from healthy people and patients, and then compared with other diagnostic tests in 200 high-risk individuals living in endemic areas. The real time RPA assay could detect 0.9 fg S. japonicum DNA within 15 min and distinguish S. japonicum from other worms. The validity analysis of RPA for the detection of S. japonicum in stool samples from 30 S. japonicum-infected patients and 30 healthy persons indicated 100% sensitivity and specificity. When testing 200 fecal or serum samples from a high-risk population, the percentage sensitivity of RPA was 100%, whereas that of indirect hemagglutination assay (IHA) and enzyme-linked immunosorbent assay (ELISA) were 80.3% and 85.2% respectively. In addition, the RPA presented better consistency with the stool-based tests than IHA and ELISA. Overall, the RPA was superior to other detection methods with respect to detection time, sensitivity, and convenience. This is the first time we applied the RPA technology to the field evaluation of S. japonicum infection. And the results suggest that RPA-based assays can be used as a promising point-of-care test for the diagnosis of schistosomiasis.

  11. Vitamin E reduces hepatic fibrosis in mice with Schistosoma japonicum infection.

    PubMed

    Wang, Xuefeng; Zhang, Rongbo; Du, Jiuwei; Hu, Youying; Xu, Lifa; Lu, Jun; Ye, Song

    2012-02-01

    To investigate whether vitamin E protects against hepatic fibrosis in mice with Schistosoma japonicum infection, 24 pathogen-free Kunming mice were selected and randomly divided into four groups: control (uninfected, untreated), model (infected, untreated), low-dose intervention (infected, vitamin E-treated, 30 mg/g bodyweight/day) and high-dose intervention (infected, vitamin E-treated, 60 mg/g bodyweight/day). Mice were infected with Schistosoma japonicum by inoculating abdominal skin with snail hosts. The activities of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were detected in hepatic tissue by colorimetry. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type Ⅲ (PC-III) and type Ⅳ collagen (IV-C) were detected in the serum by radioimmunoassay. Finally, areas and numbers of granulomas were assessed through histopathology 42 days following treatment. The results revealed that mean areas of granulomas were smaller in the low- and high-dose intervention groups compared to those in the model group. Furthermore, the higher dose of vitamin E resulted in smaller granulomas than the low dose. The levels of LN, HA, PC-III and IV-C in the serum were lower following vitamin E treatment than in the model group. By contrast, activity of SOD, GPx and CAT in hepatic tissue was higher following vitamin E treatment compared to the model group. The activity of MDA was lower in hepatic tissue following vitamin E treatment compared to the model group, but was higher compared to controls. In general, the higher dose of vitamin E affected measurements to a greater extent than the lower dose. In conclusion, vitamin E treatment may reduce the growth of granulomas, slowing the process of hepatic fibrosis, and this effect may be the result of the altered activity of the oxidation-reduction enzyme system.

  12. Local Antiglycan Antibody Responses to Skin Stage and Migratory Schistosomula of Schistosoma japonicum

    PubMed Central

    Smit, Cornelis H.; Kies, Christiaan L.; McWilliam, Hamish E. G.; Meeusen, Els N. T.; Hokke, Cornelis H.

    2015-01-01

    Schistosomiasis is a tropical disease affecting over 230 million people worldwide. Although effective drug treatment is available, reinfections are common, and development of immunity is slow. Most antibodies raised during schistosome infection are directed against glycans, some of which are thought to be protective. Developing schistosomula are considered most vulnerable to immune attack, and better understanding of local antibody responses raised against glycans expressed by this life stage might reveal possible glycan vaccine candidates for future vaccine research. We used antibody-secreting cell (ASC) probes to characterize local antiglycan antibody responses against migrating Schistosoma japonicum schistosomula in different tissues of rats. Analysis by shotgun Schistosoma glycan microarray resulted in the identification of antiglycan antibody response patterns that reflected the migratory pathway of schistosomula. Antibodies raised by skin lymph node (LN) ASC probes mainly targeted N-glycans with terminal mannose residues, Galβ1-4GlcNAc (LacNAc) and Galβ1-4(Fucα1-3)GlcNAc (LeX). Also, responses to antigenic and schistosome-specific glycosphingolipid (GSL) glycans containing highly fucosylated GalNAcβ1-4(GlcNAcβ1)n stretches that are believed to be present at the parasite's surface constitutively upon transformation were found. Antibody targets recognized by lung LN ASC probes were mainly N-glycans presenting GalNAcβ1-4GlcNAc (LDN) and GlcNAc motifs. Surprisingly, antibodies against highly antigenic multifucosylated motifs of GSL glycans were not observed in lung LN ASC probes, indicating that these antigens are not expressed in lung stage schistosomula or are not appropriately exposed to induce immune responses locally. The local antiglycan responses observed in this study highlight the stage- and tissue-specific expression of antigenic parasite glycans and provide insights into glycan targets possibly involved in resistance to S. japonicum infection

  13. Integrated refolding techniques for Schistosoma japonicum MTH1 overexpressed as inclusion bodies in Escherichia coli.

    PubMed

    Feng, Yanye; Liu, Lu; Wang, Jipeng; Liu, Jian; Hu, Wei; Wang, Xiaoning; Yang, Zhong

    2012-08-01

    The full-length cDNA of MTH1in Schistosoma japonicum was previously isolated. However, insoluble protein expression in Escherichia coli is the biggest bottleneck limiting biological and biophysical studies. Protein aggregation could not be significantly prevented using solubilization or refolding techniques, and denatured MTH1 protein could not be refolded to the native monomer form. Hence, integrating several refolding techniques within the protein refolding process of MTH1, a large amount of active MTH1 was obtained for protein crystallization. We primarily utilized the two-step-denaturing and refolding method and the protein refolding screening technique, as well as the continuous dialysis method. First, we identified the refolding buffer composition that allowed for successful refolding to overcome protein precipitation. Next, we used the two-step-denaturing and refolding method and the continuous dialysis method to suppress protein aggregation. In the end, we obtained 15 mg of active MTH1 monomer with 95% purity from 0.5l medium. Integrated refolding techniques proved to be excellent for obtaining the native monomer of S. japonicum MTH1 from inclusion bodies, paving the way for future biological and biophysical studies. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

  14. The temperature--dependent expression of GST of Schistosoma japonicum (Philippine strain).

    PubMed

    Cai, Z H; Song, G C; Xu, Y X; Liu, S X

    1993-03-01

    Obtained from pSj5, the cDNA gene encoding GST antigen of Schistosoma japonicum (Philippine strain) was ligated with efficient temperature-dependent PBV220 vector which was constructed in CAPM, and then introduced into host bacterium-DH5 alpha (E. coli) by transformation. Transformants were selected by ampicillin and recombinant clones were identified by restriction mapping. The result showed that recombinant clone 43 was the one carrying recombinant plasmid PBV 220 with the correct insertion of the gene fragment. The GST expression ability of clone 43 was investigated by GST enzymic activity assay and SDS-PAGE. A relatively high level of GST enzymic activity was expressed by this clone under the temperature-dependent condition, that is, cultured at 30 degrees C and expressed at 42 degrees C. A more strongly stained 26 kDa protein band was identified by SDS-PAGE. The result indicated that GST of S. japonicum (Philippine strain) could be expressed not only by IPTG induction, but also by the temperature-dependent method.

  15. Molecular cloning and characterization of glutamine synthetase, a tegumental protein from Schistosoma japonicum.

    PubMed

    Qiu, Chunhui; Hong, Yang; Cao, Yan; Wang, Fei; Fu, Zhiqiang; Shi, Yaojun; Wei, Meimei; Liu, Shengfa; Lin, Jiaojiao

    2012-12-01

    Glutamine synthetase catalyzes the synthesis of glutamine, providing nitrogen for the production of purines, pyrimidines, amino acids, and other compounds required in many pivotal cellular events. Herein, a full-length cDNA encoding Schistosoma japonicum glutamine synthetase (SjGS) was isolated from 21-day schistosomes. The entire open reading frame of SjGS contains a 1,095-bp coding region corresponding to 364 amino acids with a calculated molecular weight of 40.7 kDa. NCBIP blast shows that the putative amino acid of SjGS contains a classic β-grasp domain and a catalytic domain of glutamine synthetase. The relative mRNA expression of SjGS was evaluated in 7-, 13-, 21-, 28-, 35-, and 42-day worms of S. japonicum in the final host and higher expression at day 21, and 42 worms were observed. This protein was also detected in worm extracts using Western blot. Immunofluorescence studies indicated that the SjGS protein was mainly distributed on tegument and parenchyma in 28-day adult worms. The recombinant glutamine synthetase with a molecular weight of 45 kDa was expressed in Escherichia coli and purified in its active form. The enzyme activity of the recombinant protein was 3.30 ± 0.67 U.μg-1. The enzyme activity was highly stable over a wide range of pH (6-9) and temperature (25-40 °C) under physiological conditions. The transcription of SjGS was upregulated in praziquantel-treated worms at 2-, 4-, and 24-h posttreatment compared with the untreated control. As a first step towards the clarification of the role of glutamine synthetase in schistosome species, we have cloned and characterized cDNAs encoding SjGS in S. japonicum, and the data presented suggest that SjGS is an important molecule in the development of the schistosome.

  16. Geographic strain differentiation of Schistosoma japonicum in the Philippines using microsatellite markers

    PubMed Central

    Moendeg, Kharleezelle J.; Angeles, Jose Ma M.; Nakao, Ryo; Leonardo, Lydia R.; Fontanilla, Ian Kendrich C.; Goto, Yasuyuki; Kirinoki, Masashi; Villacorte, Elena A.; Rivera, Pilarita T.; Inoue, Noboru; Chigusa, Yuichi

    2017-01-01

    Background Microsatellites have been found to be useful in determining genetic diversities of various medically-important parasites which can be used as basis for an effective disease management and control program. In Asia and Africa, the identification of different geographical strains of Schistosoma japonicum, S. haematobium and S. mansoni as determined through microsatellites could pave the way for a better understanding of the transmission epidemiology of the parasite. Thus, the present study aims to apply microsatellite markers in analyzing the populations of S. japonicum from different endemic areas in the Philippines for possible strain differentiation. Methodology/ Principal findings Experimental mice were infected using the cercariae of S. japonicum collected from infected Oncomelania hupensis quadrasi snails in seven endemic municipalities. Adult worms were harvested from infected mice after 45 days of infection and their DNA analyzed against ten previously characterized microsatellite loci. High genetic diversity was observed in areas with high endemicity. The degree of genetic differentiation of the parasite population between endemic areas varies. Geographical separation was considered as one of the factors accounting for the observed difference between populations. Two subgroups have been observed in one of the study sites, suggesting that co-infection with several genotypes of the parasite might be present in the population. Clustering analysis showed no particular spatial structuring between parasite populations from different endemic areas. This result could possibly suggest varying degrees of effects of the ongoing control programs and the existing gene flow in the populations, which might be attributed to migration and active movement of infected hosts from one endemic area to another. Conclusions/ Significance Based on the results of the study, it is reasonable to conclude that genetic diversity could be one possible criterion to assess the

  17. Geographic strain differentiation of Schistosoma japonicum in the Philippines using microsatellite markers.

    PubMed

    Moendeg, Kharleezelle J; Angeles, Jose Ma M; Nakao, Ryo; Leonardo, Lydia R; Fontanilla, Ian Kendrich C; Goto, Yasuyuki; Kirinoki, Masashi; Villacorte, Elena A; Rivera, Pilarita T; Inoue, Noboru; Chigusa, Yuichi; Kawazu, Shin-Ichiro

    2017-07-01

    Microsatellites have been found to be useful in determining genetic diversities of various medically-important parasites which can be used as basis for an effective disease management and control program. In Asia and Africa, the identification of different geographical strains of Schistosoma japonicum, S. haematobium and S. mansoni as determined through microsatellites could pave the way for a better understanding of the transmission epidemiology of the parasite. Thus, the present study aims to apply microsatellite markers in analyzing the populations of S. japonicum from different endemic areas in the Philippines for possible strain differentiation. Experimental mice were infected using the cercariae of S. japonicum collected from infected Oncomelania hupensis quadrasi snails in seven endemic municipalities. Adult worms were harvested from infected mice after 45 days of infection and their DNA analyzed against ten previously characterized microsatellite loci. High genetic diversity was observed in areas with high endemicity. The degree of genetic differentiation of the parasite population between endemic areas varies. Geographical separation was considered as one of the factors accounting for the observed difference between populations. Two subgroups have been observed in one of the study sites, suggesting that co-infection with several genotypes of the parasite might be present in the population. Clustering analysis showed no particular spatial structuring between parasite populations from different endemic areas. This result could possibly suggest varying degrees of effects of the ongoing control programs and the existing gene flow in the populations, which might be attributed to migration and active movement of infected hosts from one endemic area to another. Based on the results of the study, it is reasonable to conclude that genetic diversity could be one possible criterion to assess the infection status in highly endemic areas. Genetic surveillance using

  18. A strategy for emergency treatment of Schistosoma japonicum-infested water

    PubMed Central

    2011-01-01

    Background Schistosomiasis japonica, caused by contact with Schistosoma japonicum cercaria-infested water when washing, bathing or production, remains a major public-health concern in China. The purpose of the present study was to investigate the effect of a suspension concentrate of niclosamide (SCN) on killing cercaria of S. japonicum that float on the water surface, and its toxicity to fish, so as to establish an emergency-treatment intervention for rapidly killing cercaria and eliminating water infectivity. Results At 30 min after spraying 100 mg/L SCN, with niclosamide dosages of 0.01, 0.02, 0.03, 0.04 g/m2, the water infectivity reduced significantly and no infectivity was found at 60 min after spraying SCN. The surface of static water was sprayed with 100 mg/L SCN, the peak concentration was found at 0 min, and the solution diffused to site with a water depth of 10 cm after 10 min. 30 min later, SCN diffused to the whole water body, and distributed evenly. After spraying 100 mg/L SCN onto the surface of the water with a volume of(3.14 × 202×50)cm3, with niclosamide dosages of 0.02 g/m2, 96 h later, no death of zebra fish was observed. Conclusions By spraying 100 mg/L SCN, with a niclosamide dosage of 0.02 g/m2 onto the surface of S. japonicum-infested water, infectivity of the water can be eliminated after 30-60 min, and there is no evident toxicity to fish. This cercaria-killing method, as an emergency-treatment intervention for infested water, can be applied in those forecasting and early warning systems for schistosomiasis. PMID:22047607

  19. Tim-3 induces Th2-biased immunity and alternative macrophage activation during Schistosoma japonicum infection.

    PubMed

    Hou, Nan; Piao, Xianyu; Liu, Shuai; Wu, Chuang; Chen, Qijun

    2015-08-01

    T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected with Schistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response against S. japonicum infection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4(+) and CD8(+) T cells, NK1.1(+) cells, and CD11b(+) cells from the livers of S. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8(+) T cells or CD11b(+) cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbers in vitro and in vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b(+) cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection.

  20. Tim-3 Induces Th2-Biased Immunity and Alternative Macrophage Activation during Schistosoma japonicum Infection

    PubMed Central

    Hou, Nan; Piao, Xianyu; Liu, Shuai; Wu, Chuang

    2015-01-01

    T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected with Schistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response against S. japonicum infection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4+ and CD8+ T cells, NK1.1+ cells, and CD11b+ cells from the livers of S. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8+ T cells or CD11b+ cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbers in vitro and in vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b+ cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection. PMID:25987707

  1. Discovery and Confirmation of Ligand Binding Specificities of the Schistosoma japonicum Polarity Protein Scribble

    PubMed Central

    Piao, Xianyu; Hou, Nan; Liu, Shuai; Gao, Youhe; Wang, Heng; Chen, Qijun

    2014-01-01

    Background Schistosomiasis is a chronic debilitating parasitic disease that afflicts more than 200 million individuals worldwide. Long-term administration of chemotherapy with the single available drug, praziquantel, has led to growing concerns about drug resistance. The PSD-95/Dlg/ZO-1 (PDZ) domain is an important module found in many scaffolding proteins, which has been recognized as promising targets for the development of novel drugs. However, the parasite-derived PDZ domains and their associated functions are still largely unknown. Methodology/Principal Findings The gene encoding the Schistosoma japonicum Scribble protein (SjScrib) was identified by homologous search with the S. mansoni Scrib sequence. By screening an arbitrary peptide library in yeast two-hybrid (Y2H) assays, we identified and confirmed the ligand binding specificity for each of the four PDZ domains of SjScrib. Both SjScrib-PDZ1 and SjScrib-PDZ3 recognize type I C-terminal PDZ-domain binding motifs (PBMs), which can be deduced as consensus sequences of -[Φ][x][E][TS][x][ILF] and -[x][RKx][ETS][T][WΦ][ILV], respectively. SjScrib-PDZ2 prefers stringent type II C-terminal PBMs, which significantly differs from that of its human ortholog. SjScrib-PDZ4 binds to typical II C-terminal PBMs with a consensus sequence -[x][FW][x][LI][x][LIV], in which the aromatic residue Phe is predominantly selected at position -4. The irregular and unconventional internal ligand binding specificities for the PDZ domains of SjScrib were confirmed by point mutations of the key amino acids within the ligand binding motifs. We also compared the differences in ligand specificities between SjScrib-PDZs and hScrib-PDZs, and explored the structural basis for the ligand binding properties of SjScrib-PDZs. Conclusions/Significance In this study, we characterized and confirmed the ligand binding specificities of all four PDZ domains of SjScrib for the first time. We denoted the differential ligand binding specificities

  2. Utilization of ELISA Using Thioredoxin Peroxidase-1 and Tandem Repeat Proteins for Diagnosis of Schistosoma japonicum Infection among Water Buffaloes

    PubMed Central

    Angeles, Jose Ma. M.; Goto, Yasuyuki; Kirinoki, Masashi; Asada, Masahito; Leonardo, Lydia R.; Rivera, Pilarita T.; Villacorte, Elena A.; Inoue, Noboru; Chigusa, Yuichi; Kawazu, Shin-ichiro

    2012-01-01

    Background The presence of animal reservoirs in Schistosoma japonicum infection has been a major obstacle in the control of schistosomiasis. Previous studies have proven that the inclusion of control measures on animal reservoir hosts for schistosomiasis contributed to the decrease of human cases. Animal surveillance should therefore be included to strengthen and improve the capabilities of current serological tests. Methodology/Principal Findings Thioredoxin peroxidase-1 (SjTPx-1) and four tandem repeat proteins (Sj1TR, Sj2TR, Sj4TR, Sj7TR) were initially evaluated against human sera. The previous test showed high sensitivity and specificity for antibody detection against SjTPx-1 and Sj7TR. In this study, the immunodiagnostic potential of these recombinant proteins was evaluated using enzyme-linked immunoassay on 50 water buffalo serum samples collected in Cagayan, the Philippines as compared with the soluble egg antigen (SEA). For specificity, 3 goat serum samples positive with Fasciola hepatica were used and among the antigens used, only SEA showed cross-reaction. Stool PCR targeting the S. japonicum 82 bp mitochondrial NAD 1 gene was done to confirm the true positives and served as the standard test. Twenty three samples were positive for stool PCR. SjTPx-1 and Sj1TR gave the highest sensitivity among the recombinant proteins tested for water buffalo samples with 82.61% and 78.26% respectively which were higher than that of SEA (69.57%). Conclusions/Significance These results prove that SjTPx-1 works both for humans and water buffaloes making it a good candidate antigen for zoonotic diagnosis. Sj1TR showed good results for water buffaloes and therefore can also be used as a possible candidate for detecting animal schistosome infection. PMID:22953018

  3. Host serum miR-223 is a potential new biomarker for Schistosoma japonicum infection and the response to chemotherapy

    PubMed Central

    2013-01-01

    Background Numerous studies have shown that aberrant microRNA (miRNA) expression is associated with the pathogenesis and progression of various human diseases. Hence, serum miRNAs are considered to be potential biomarkers for the diagnosis of human diseases. This study examined whether several miRNAs known to be commonly deregulated in liver diseases are deregulated in the serum of hosts with hepatic schistosomiasis, and thus whether they could serve as potential markers for detection of schistosome infection and evaluation of the effectiveness of chemotherapy. Methods We analyzed the serum levels of six selected candidate miRNA molecules (miR-146b, miR-122, miR-223, miR-199a-5p, miR-199a-3p, miR-34a) from mice, rabbits, buffalos and humans infected with Schistosoma japonicum using qPCR. We evaluated liver pathology by determining the hydroxyproline content in liver tissues. Primary resident liver cells were isolated to quantify the expression level of deregulated miRNAs. Bioinformatics analyses were also conducted to assess the potential function of miR-223. Results Using a mouse model of Schistosoma japonicum infection, we found that the expression level of serum miR-223 was significantly elevated after infection, but returned to near normal levels after the treatment with praziquantel (PZQ). Importantly, the level of serum miR-223 reflected the extent of liver pathology post-infection. We validated the elevated level of the circulating miR-223 in serum samples of other host species including rabbits, buffalos and humans. In addition, our results showed that miR-223 was primarily located in the Kupffer cells, but its expression levels were significantly up-regulated in hepatocytes, hepatic stellate cells and Kupffer cells after infection. Bioinformatics analyses revealed a potential functional role of miR-223 in transcription regulator activity, transcription factor activity and DNA binding. Conclusions This study suggested that the circulating miR-223 could

  4. An IL-13 Promoter Polymorphism Associated with Liver Fibrosis in Patients with Schistosoma japonicum

    PubMed Central

    Long, Xin; Chen, Qian; Zhao, Jianping; Rafaels, Nicholas; Mathias, Priyanka; Liang, Huifang; Potee, Joseph; Campbell, Monica; Zhang, Bixiang; Gao, Li; Georas, Steve N.; Vercelli, Donata; Beaty, Terri H.; Ruczinski, Ingo; Mathias, Rasika; Barnes, Kathleen C.; Chen, Xiaoping

    2015-01-01

    The aim of this study was to determine whether two polymorphisms in the gene encoding IL13 previously associated with Schistosoma hematobium (S. hematobium) and S. mansoni infection are associated with S. japonicum infection. Single nucleotide polymorphisms (SNPs) rs1800925 (IL13/-1112C>T) and rs20541 (IL13R130Q) were genotyped in 947 unrelated individuals (307 chronically infected, 339 late-stage with liver fibrosis, 301 uninfected controls) from a schistosomiasis-endemic area of Hubei province in China. Regression models were used to evaluate allelic and haplotypic associations with chronic and late-stage schistosomiasis adjusted for non-genetic covariates. Expression of IL-13 was measured in S. japonicun-infected liver fibrosis tissue and normal liver tissue from uninfected controls by immunohistochemistry (IHC). The role of rs1800925 in IL-13 transcription was further determined by Luciferase report assay using the recombinant PGL4.17-rs180092 plasmid. We found SNP rs1800925T was associated with late-stage schistosomiasis caused by S. japonicum but not chronic schistosomiasis (OR = 1.39, 95%CI = 1.02–1.91, p = 0.03) and uninfected controls (OR = 1.49, 95%CI = 1.03–2.13, p = 0.03). Moreover, the haplotype rs1800925T-rs20541C increased the risk of disease progression to late-stage schistosomiasis (OR = 1.46, p = 0.035), whereas haplotype rs1800925C-rs20541A showed a protective role against development of late-stage schistosomiasis (F = 0.188, OR = 0.61, p = 0.002). Furthermore, S. japonicum-induced fibrotic liver tissue had higher IL13 expression than normal liver tissue. Plasmid PGL4.17-rs1800925T showed a stronger relative luciferase activity than Plasmid PGL4.17-rs1800925C in 293FT, QSG-7701 and HL-7702 cell lines. In conclusion, the functional IL13 polymorphism, rs1800925T, previously associated with risk of schistosomiasis, also contributes to risk of late-stage schistosomiasis caused by S. japonicum. PMID:26258681

  5. A potential impact of climate change and water resource development on the transmission of Schistosoma japonicum in China.

    PubMed

    Yang, G J; Vounatsou, P; Zhou, X N; Tanner, M; Utzinger, J

    2005-03-01

    There is growing consensus among climate modellers that the unusual global warming observed in the last decades of the 20th century is primarily forced by human activities, namely greenhouse gas increases in the atmosphere. Global warming will trigger alterations in physical and biological systems, including shifts in the spatio-temporal distribution of disease vectors, but the nature and extent of these changes are poorly understood. The purpose of the present study was to assess the potential impact of climate change and water resource development on the distribution of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. We employed two 30-year composite datasets comprising average monthly temperatures collected at 623 observing stations throughout China, spanning the periods 1961-1990 and 1971-2000. Temperature changes were assessed spatially between the 1960s and 1990s for January, as this is the critical month for survival of O. hupensis. Our database shows that January temperatures increased at 590 stations (94.7%), and that China's average January temperature in the 1990s was 0.96 degrees C higher than 30 years earlier. The historical 0-1 degrees C January isotherm, which was considered the approximate northern limit of S. japonicum transmission, has shifted from 33 degrees 15' N to 33 degrees 41' N, expanding the potential transmission area by 41,335 km2. This translates to an additional 20.7 million people at risk of schistosomiasis. Two lakes are located in this new transmission area that form part of the proposed South-North water transfer project. Climate change, coupled with water resource developments in China, may pose additional challenges for the control of schistosomiasis.

  6. Expression Profile of the Schistosoma japonicum Degradome Reveals Differential Protease Expression Patterns and Potential Anti-schistosomal Intervention Targets

    PubMed Central

    Liu, Shuai; Cai, Pengfei; Piao, Xianyu; Hou, Nan; Zhou, Xiaosu; Wu, Chuang; Wang, Heng; Chen, Qijun

    2014-01-01

    Blood fluke proteases play pivotal roles in the processes of invasion, nutrition acquisition, immune evasion, and other host-parasite interactions. Hundreds of genes encoding putative proteases have been identified in the recently published schistosome genomes. However, the expression profiles of these proteases in Schistosoma species have not yet been systematically analyzed. We retrieved and culled the redundant protease sequences of Schistosoma japonicum, Schistosoma mansoni, Echinococcus multilocularis, and Clonorchis sinensis from public databases utilizing bioinformatic approaches. The degradomes of the four parasitic organisms and Homo sapiens were then comparatively analyzed. A total of 262 S. japonicum protease sequences were obtained and the expression profiles generated using whole-genome microarray. Four main clusters of protease genes with different expression patterns were identified: proteases up-regulated in hepatic schistosomula and adult worms, egg-specific or predominantly expressed proteases, cercaria-specific or predominantly expressed proteases, and constantly expressed proteases. A subset of protease genes with different expression patterns were further validated using real-time quantitative PCR. The present study represents the most comprehensive analysis of a degradome in Schistosoma species to date. These results provide a firm foundation for future research on the specific function(s) of individual proteases and may help to refine anti-proteolytic strategies in blood flukes. PMID:25275570

  7. Cloning and characterization of a bone morphogenetic protein homologue of Schistosoma japonicum.

    PubMed

    Liu, Rong; Zhao, Qin-ping; Ye, Qing; Xiong, Tao; Tang, Chun-lian; Dong, Hui-fen; Jiang, Ming-sen

    2013-09-01

    Bone morphogenetic proteins (BMPs) are known to play an important role in the regulation of cell proliferation, survival, differentiation and apoptosis in many vertebrates and invertebrates through the TGF-β signaling pathway. Although the TGF-β signaling pathway exists in schistosomes, BMP homologue, a ligand of TGF-β in Schistosoma japonicum, has not yet been identified. In this study, a BMP homologue of S. japonicum was cloned and characterized. The full length SjBMP cDNA is 3,020 bp and encodes 928 amino acids, which include a TGF-β superfamily conserved domain at the C-terminus. BLAST analysis showed that, SjBMP has 68%, 51% and 43% homology with BMP from Schistosoma mansoni, Schmidtea mediterranea and Dugesia japonica at the amino acid level, respectively. According to data from real-time PCR, SjBMP was expressed in lung-stage schistosomula, 21-day liver-stage schistosomula, 50-day adult worms (the male and female), and eggs. The PCR data also indicated that, there was a ≈ 27- and ≈ 37-fold increase of SjBMP transcripts in the lung-stage schistosomula and eggs, respectively, and that there was relatively more SjBMP transcript in the adult male worm than in the adult female, in which the hepatic schistosomula was set as the calibrator for calculation. In situ hybridization based on FITC-labeled specific antisense oligonucleotide probes showed that SjBMP mRNA localized to the ovary of female worms and the integument and epithelium of female and male worms. After treatment with double-stranded RNA (dsRNA) at a concentration of 8 × 10(-2) μg/ml, which was added to the culture medium every other day for a week, the level of SjBMP mRNA in the cultured adult mixed-sex S. japonicum decreased at a range of ≈ 25-98% within 7 days compared with the level of SjBMP mRNA in the blank control group. On the 2nd day, the number of eggs produced per pair of worms decreased 28.7%, and the percent of normal eggs also decreased (12.7% vs. 4.3%) in the SjBMP ds

  8. Molluscicidal activity of the plant Eupatorium adenophorum against Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum.

    PubMed

    Zou, F C; Duan, G; Xie, Y J; Zhou, Y; Dong, G D; Lin, R Q; Zhu, X Q

    2009-09-01

    The potential molluscicidal activities of aqueous extracts of Eupatorium adenophorum have recently been evaluated against Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. The snails were continuously exposed to extracts of the leaves, roots or stems [each at concentrations of 0.27%, 0.50% and 0.86% (w/v)], with survival recorded 6, 12, 24, 30, 36, 48, 52, 58, 70, 76, 82 and 96 h after the start of the exposure. Even at the lowest concentration tested (0.27%), the leaf extract caused mortality in excess of 50% after 58 h and 100% mortality after 82 h. This extract was significantly more effective against O. hupensis than the stem or root extract (P<0.05) but there was no statistically significant difference between the root and stem extracts in their molluscicidal effects (P>0.05). These preliminary results indicate that E. adenophorum may potentially provide a new molluscicide that could give effective and environmentally-friendly control of schistosomiasis in humans and livestock. The toxicity of E. adenophorum extracts, or molluscicidal compounds isolated from such extracts, to other snail hosts of human parasites and to non-target species of aquatic life will be investigated.

  9. Exosome-like vesicles derived by Schistosoma japonicum adult worms mediates M1 type immune- activity of macrophage.

    PubMed

    Wang, Lifu; Li, Zhitao; Shen, Jia; Liu, Zhen; Liang, Jinyi; Wu, Xiaoying; Sun, Xi; Wu, Zhongdao

    2015-05-01

    Exosomes are 30-100-nm membrane vesicles of endocytic origin that are released into the extracellular space upon fusion of the multi-vesicular bodies (MVB) with the plasma membrane, while initial studies described that the role of exosomes was a reticulocyte cargo-disposal mechanism allowing remodeling of the plasma membrane during the maturation of reticulocytes to erythrocytes. Recent studies indicate that exosomes are secreted by most cells and pathogens and play an important role in intercellular signaling and exert regulatory function by carrying bioactive molecules. As numerous pathogens, adult worm of Schistosoma japonicum (S. japonicum) reside in mesenteric veins of definitive host including man and mammal animals. It was reported that the worms or the eggs also have specialized secretion systems to export effector proteins or other molecules into host target cells. However, the mechanisms involved remained unclear. This study investigated the isolation of the exosome-like vesicles secreted by S. japonicum adult worms and its immune activity on microphage in vitro. In this report, we identified exosome-based secretion as a new mechanism for protein secretion by S. japonicum. Electron microscopy tomography revealed the previously unidentified ultrastructural detail of exosome-like vesicles with high resolution; they were found to be typical spherical shape and to have a diverse population that varies in size of 30-100 nm. Exosome-like vesicles isolated from S. japonicum contained a significantly different protein compared with debris pelleted and the apoptosis body. We also demonstrate that macrophages were preferentially differentiated into the M1 subtype while being treated with S. japonicum exosome-like vesicles. This study reveals there are exosome-like vesicles derived by S. japonicum adult worms, and the exosome-like vesicles can mediate M1-type immune- activity of macrophage.

  10. [Identification of early diagnostic molecules in soluble egg antigen of Schistosoma japonicum by MASS].

    PubMed

    Wang, Jie; Song, Li-Jun; He, Wei; Yin, Xu-Ren; Qian, Chun-Yan; Zhang, Wei; Xu, Yong-Liang; Cao, Guo-Qun; Ke, Xue-Dan; Yu, Chuan-Xin

    2012-04-01

    To identify the molecules of soluble egg antigen (SEA) for early diagnosis of Schistosoma japonicum infection by two-dimensional electrophoresis (2-DE), immunoblotting and liquid chromatography with tandem mass spectrometry (LC-MS/MS). The 2-DE of SEA was executed through first direction isoelectric focusing (IEF) in immobilized pH gradient gel 3-10 (IPG3-10) and second direction SDS-PAGE. The protein dots of SEA on the SDS-PAGE gel were transferred to nitrocellulose membrane. These nitrocellulose membranes were responded to the sera of healthy, sera of mice at 1 week, 2 weeks and 6 weeks post-infection respectively, then the membrane color was developed with the second antibody of HRP labeled goat anti -mouse IgG conjugate and substrate DAB. The protein dots recognized by sera of mice in the early stage of schistosome infection were identified by LC-MS/MS. After matching and analyzing the Western blot patterns of SEA responding to acute infection sera (1 week and 2 weeks post-infection), chronic infection sera (6 weeks post-infection) and healthy sera by PDQuest 1.0 software, two protein dots were found to be recognized by sera of mice at 1 week, 2 weeks and 6 weeks post-infection, and three protein dots were only recognized by the sera of mice at 6 weeks post-infection, no protein dot was recognized by healthy mouse sera. The data of LC-MS/MS showed that the two protein molecules recognized by the sera of mice with schistosome infection in the early stage were heat shock protein 70 (HSP70) and 78 kDa glucose-regulated protein (Grp78/Bip) respectively. The results of this study preliminarily indicate that HSP70 and Grp78 in SEA have early diagnostic value for S. japonicum infection.

  11. Biochemical properties and vaccine effect of recombinant TPx-3 from Schistosoma japonicum.

    PubMed

    Han, Yanhui; Zhao, Bin; Zhang, Min; Hong, Yang; Han, Hongxiao; Cao, Xiaodan; Lu, Ke; Lin, Jiaojiao; Fu, Zhiqiang

    2017-04-01

    Thioredoxin peroxidases (TPxs) play an important role in maintaining redox homeostasis and in protecting organisms from the accumulation of toxic reactive oxygen species (ROS). In this study, we isolated the thioredoxin peroxidase-3 gene of Schistosoma japonicum, SjTPx-3. The open reading frame (ORF) of SjTPx-3 was 663 bp encoding 220 amino acids with a molecular weight of 24.99 kDa and an isoelectric point of 6.20. Quantitative real-time reverse transcription-polymerase chain reaction indicated that SjTPx-3 was expressed in all different stages of the parasites, with highest expression in 35-day-old worms. The ORF of SjTPx-3 was subcloned into pET-32a (+) vectors and expressed in Escherichia coli. Recombinant SjTPx-3 (rSjTPx-3) was expressed as a soluble protein with good antigenicity, as demonstrated by western blotting. Immunohistochemical analysis revealed that SjTPx-3 was mainly localized on the tegument of the parasites. Mice vaccinated with rSjTPx-3 had a 37.02% (P < 0.05) reduction in worm burden and 56.52% (P < 0.05) reduction in liver egg production compared with control, unvaccinated mice. Enzyme-linked immunosorbent assay analysis demonstrated that rSjTPx-3 could induce high levels of anti-rSjTPx-3-specific IgG, IgG1, and IgG2a antibodies. Characteristic Th1 and Th2 immune response cytokines were detected by flow cytometry and were increased by rSjTPx-3. Taken together, these results suggest that SjTPx-3 is an antioxidant enzyme responsible for protecting S. japonicum from oxidative stress. rSjTPx-3 may represent a potential vaccine candidate and/or new drug target for patients with schistosomiasis.

  12. Schistosoma japonicum: susceptibility of neonate mice born to infected and noninfected mothers following subsequent challenge.

    PubMed

    Zhao, F; Huang, X; Hou, X; Deng, Y; Wu, M; Guan, F; Liu, W; Li, Y; Lei, J

    2013-01-01

    This study was to investigate the differences between neonate mice born to Schistosoma japonicum-infected mothers and those born to noninfected mothers in subsequent challenge. The intensity of infection (evidenced by worm burden and liver egg burden) and liver immunopathology (number and size of liver granulomas) were significantly reduced in neonates from infected mothers (I.M.) compared with neonates from noninfected mothers (N.M.). Anti-soluble worm antigen of S. japonicum (SWA) IgG could be detected in sera of neonates from I.M. (N.N./I.M.) at 1 week after delivery, remained a plateau for 2 weeks and gradually decreased until 8 weeks of age. Parasite-specific IgM was not detected in sera from N.N./I.M. at any time after delivery. At 6 weeks after infection, the level of anti-SWA IgG in infected neonates from I.M. (I.N./I.M.) was significantly higher than that of infected neonates from N.M. (I.N./N.M.). In addition, production of IFN-γ, IL-12 and TGF-β by cultured splenocytes from I.N./I.M. was significantly increased, while the level of IL-4 was significantly decreased when compared to those from I.N./N.M.. These data demonstrate that congenital exposure to schistosomiasis japonica may render neonatal mice born to I.M. less susceptible to subsequent challenge and result in down-regulation of both infection intensity and immunopathology.

  13. Silver-enhanced colloidal gold metalloimmunoassay for Schistosoma japonicum antibody detection.

    PubMed

    Chu, Xia; Xiang, Zhi-Feng; Fu, Xin; Wang, Shi-Ping; Shen, Guo-Li; Yu, Ru-Qin

    2005-06-01

    A silver-enhanced colloidal gold metalloimmunoassay has been proposed for the determination of Schistosoma japonicum antibody (SjAb) in rabbit serum. The adult worm antigen of S. japonicum (SjAg) was adsorbed passively on the walls of a polystyrene microwell and then reacted with the desired SjAb. The colloidal gold-labeled goat anti-rabbit IgG secondary antibody was adsorbed on the walls of the polystyrene microwells through the reaction with SjAb, followed by the silver enhancement process, dissolution of silver metal atoms in an acidic solution, and determination of dissolved silver ions by anodic stripping voltammetry (ASV) at a glassy-carbon electrode. Assay conditions were optimized, including the reaction time of SjAg with SjAb, the interaction of SjAb with the colloidal gold-labeled secondary antibody, the dilution ratio of the colloidal gold-labeled secondary antibody and the silver enhancement time. The integration of the anodic stripping peak current depended linearly on the SjAb logarithmic concentration over the range of 6.4 ng/ml to 100 microg/ml. A detection limit as low as 3.0 ng/ml SjAb was achieved, which was better than the piezoelectric body acoustic wave sensor (detection limit of 7.2 microg/ml) and the renewable amperometric immunosensor (detection limit of 0.36 microg/ml). Rabbit serum samples with various degrees of infection were analyzed, and the results demonstrate that the proposed method meets the requirements of clinical analysis.

  14. Identification and Characterization of Argonaute Protein, Ago2 and Its Associated Small RNAs in Schistosoma japonicum

    PubMed Central

    Cai, Pengfei; Piao, Xianyu; Hou, Nan; Liu, Shuai; Wang, Heng; Chen, Qijun

    2012-01-01

    Background The complex life cycle of the genus Schistosoma drives the parasites to employ subtle developmentally dependent gene regulatory machineries. Small non-coding RNAs (sncRNAs) are essential gene regulatory factors that, through their impact on mRNA and genome stability, control stage-specific gene expression. Abundant sncRNAs have been identified in this genus. However, their functionally associated partners, Argonaute family proteins, which are the key components of the RNA-induced silencing complex (RISC), have not yet been fully explored. Methodology/Principal Findings Two monoclonal antibodies (mAbs) specific to Schistosoma japonicum Argonaute protein Ago2 (SjAgo2), but not SjAgo1 and SjAgo3, were generated. Soluble adult worm antigen preparation (SWAP) was subjected to immunoprecipitation with the mAbs and the captured SjAgo2 protein was subsequently confirmed by Western blot and mass spectrometry (MS) analysis. The small RNA population associated with native SjAgo2 in adult parasites was extracted from the immunoprecipitated complex and subjected to library construction. High-through-put sequencing of these libraries yielded a total of ≈50 million high-quality reads. Classification of these small RNAs showed that endogenous siRNAs (endo-siRNAs) generated from transposable elements (TEs), especially from the subclasses of LINE and LTR, were prominent. Further bioinformatics analysis revealed that siRNAs derived from ten types of well-defined retrotransposons were dramatically enriched in the SjAgo2-specific libraries compared to small RNA libraries constructed with total small RNAs from separated adult worms. These results suggest that a key function of SjAgo2 is to maintain genome stability through suppressing the activities of retrotransposons. Conclusions/Significance In this study, we identified and characterized one of the three S. japonicum Argonautes, SjAgo2, and its associated small RNAs were found to be predominantly derived from particular

  15. The Schistosoma japonicum self-cure phenomenon in water buffaloes: potential impact on the control and elimination of schistosomiasis in China.

    PubMed

    Li, Yue-Sheng; McManus, Donald P; Lin, Dan-Dan; Williams, Gail M; Harn, Donald A; Ross, Allen G; Feng, Zheng; Gray, Darren J

    2014-03-01

    Schistosomiasis japonica, caused by Schistosoma japonicum, is an important zoonotic disease in China, the Philippines and small pockets of Indonesia. In addition to infecting people, S. japonicum can infect over 40 species of wild and domestic animals which have varying impacts on human infection. It is now generally accepted that bovines, particularly water buffaloes, are the major reservoir for human infection in China as they are naturally infected with schistosomes and deposit more eggs into the environment than humans or any other animal host. This complicates control efforts and the economic burden associated with schistosomiasis morbidity and mortality has taken its toll on both human and livestock populations. Over the last 50years, the schistosomiasis control program in China has made great strides in reducing prevalence and morbidity, and the Chinese authorities now aim to eliminate the disease nationwide in the next decade. Current Chinese control strategies place particular importance on interventions targeting bovines including: praziquantel treatment, barrier farming to prevent grazing in transmission areas, their replacement with mechanized tractors and possible bovine vaccination. A number of studies have shown that in the period following S. japonicum infection, the worm burden drops sharply in water buffaloes and some other animal hosts such as pigs. This is due to a self-cure phenomenon whereby there is parasite clearance by both immune and non-immune factors. Here we review studies investigating the self-cure effect, paying particular attention to S. japonicum infection in water buffaloes, and discuss its potential impact on the future schistosomiasis control and elimination efforts in China. Further understanding of the mechanism of self-cure in water buffaloes could be important for future schistosome vaccine design and delivery. Copyright © 2014. Published by Elsevier Ltd.

  16. [Preliminary study on pro-apoptotic gene BAD of Schistosoma japonicum].

    PubMed

    Ma, Qian-qian; Hong, Yang; Han, Hong-xiao; Lu, Kan; Ma, Shuai; Wang, Tao; Liu, Yan-tao; Han, Qian; Fu, Zhi-qiang; Lu, Ke; Li, Hao; Li, Xiang-rui; Lin, Jiao-jiao

    2015-04-01

    To understand the characteristics of pro-apoptotic gene SjBAD of Schistosoma japonicum, such as its biology, immunology, and transcriptional expression, and evaluate its potential of the recombinant protein as a vaccine candidate for schistosomiasis. SjBAD was amplified by PCR and subeloned into a pET-28a(+) vector, and the recombinant plasmid was transformed into competent E. coli BL21 for producing recombinant protein. The expressions of SjBAD in different development stages of schistosomula and 42-day male and female worms were determined by real-time PCR. The immunogenicity of the recombinant protein was analyzed by Western blotting and ELISA. The potential of this protein as a vaccine candidate molecule was assessed by testing the worm reduction rate and liver egg reduction rate in the BALB/c mice immunized by the recombinant antigen SjBAD. SjBAD was successfully cloned, the recombinant plasmid pET-28a(+)-SjBAD was successfully expressed in E. coli, and the molecular weight of the recombinant protein was around 22 kDa. Western-blotting showed that the recombinant protein had good immunogenicity. The recombinant protein could induce high level of specific IgG antibodies in the BALB/c mice. SjBAD was expressed in all tested 7-, 14-, 21-, 28-, 35- and 42-day worms, and was highly expressed in 14-day schistosomula, while the expression level in 42-day male worms was higher than that in 42-day female worms. Two in- dependent animal trials showed that 30.82% and 27.87% worm reduction rates, as well as 42.52% and 45.84% liver eggs reduction rates were obtained in the rSjBAD vaccinated group compared with those of the blank control group (both P < 0.05). The proapoptotic gene SjBAD is successfully cloned and expressed. The gene is expressed in different development stages of S. japonicum. The rSjBAD vaccinated BALB/c mice can obtain a partial protective immunity against S. japonicum infection.

  17. A Deep Analysis of the Small Non-Coding RNA Population in Schistosoma japonicum Eggs

    PubMed Central

    Cai, Pengfei; Piao, Xianyu; Hao, Lili; Liu, Shuai; Hou, Nan; Wang, Heng; Chen, Qijun

    2013-01-01

    Background Schistosoma japonicum is a parasitic flatworm that causes zoonotic schistosomiasis. The typical outcome of schistosomiasis is hepatic granuloma and fibrosis, which is primarily induced by soluble egg-derived antigens. Although schistosomal eggs represent an important pathogenic stage to the host, the biology of this critical stage is largely unknown. We previously investigated the expression profiles of sncRNAs during different developmental stages of this parasite. However, using small RNA extracted from egg-deposited liver tissues generated limited information about sncRNAs in eggs. Here, we characterized the complete small RNAome in this stage of the parasite after optimization of RNA purification. Methodology and Principal Findings A library, SjE, was constructed with the small RNA extracted from S. japonicum eggs and subjected to high-throughput sequencing. The data were depicted by comprehensive bioinformatic analysis to explore the expression features of sncRNAs in the egg stage. MicroRNAs accounted for about one quarter of the total small RNA population in this stage, with a strongly biased expression pattern of certain miRNA family members. Sja-miR-71, sja-miR-71-5p, and sja-miR-36-3p were suggested to play important roles in embryo development. A panel of transfer RNA fragments (tRFs) precisely processed from the 5′ end of mature tRNAs was identified for the first time, which represented a strong egg stage-biased expression. The tRNA-Ala derived small RNAs were the most highly expressed Sj-tRFs in eggs. Further, the expression of siRNAs from 29 types of well-defined transposable elements (TEs) was observed to be relatively stable among different developmental stages. Conclusions and Significance In this study, we characterized the sncRNA profile in the egg stage of S. japonicum. Featured expression of sncRNAs, especially the tRNA-derived small RNAs, was identified, which was further compared with that of other developmental stages. These

  18. Characterisation of a secretory serine protease inhibitor (SjB6) from Schistosoma japonicum

    PubMed Central

    2014-01-01

    Background Proteins belonging to the serine protease inhibitor (serpin) superfamily play essential physiological roles in many organisms. In pathogens, serpins are thought to have evolved specifically to limit host immune responses by interfering with the host immune-stimulatory signals. Serpins are less well characterised in parasitic helminths, although some are thought to be involved in mechanisms associated with host immune modulation. In this study, we cloned and partially characterised a secretory serpin from Schistosoma japonicum termed SjB6, these findings provide the basis for possible functional roles. Methods SjB6 gene was identified through database mining of our previously published microarray data, cloned and detailed sequence and structural analysis and comparative modelling carried out using various bioinformatics and proteomics tools. Gene transcriptional profiling was determined by real-time PCR and the expression of native protein determined by immunoblotting. An immunological profile of the recombinant protein produced in insect cells was determined by ELISA. Results SjB6 contains an open reading frame of 1160 base pairs that encodes a protein of 387 amino acid residues. Detailed sequence analysis, comparative modelling and structural-based alignment revealed that SjB6 contains the essential structural motifs and consensus secondary structures typical of inhibitory serpins. The presence of an N-terminal signal sequence indicated that SjB6 is a secretory protein. Real-time data indicated that SjB6 is expressed exclusively in the intra-mammalian stage of the parasite life cycle with its highest expression levels in the egg stage (p < 0.0001). The native protein is approximately 60 kDa in size and recombinant SjB6 (rSjB6) was recognised strongly by sera from rats experimentally infected with S. japonicum. Conclusions The significantly high expression of SjB6 in schistosome eggs, when compared to other life cycle stages, suggests a possible

  19. Mefloquine in combination with hemin causes severe damage to adult Schistosoma japonicum in vitro.

    PubMed

    Xiao, Shu-hua; Qiao, Chunhua; Xue, Jian; Wang, Lili

    2014-03-01

    In order to explore the interaction of mefloquine with hemin against adult Schistosoma japonicum in vitro, the 50% and 95% lethal concentration (LC50 and LC95) of mefloquine and hemin against schistosomes, some factors, such as other iron providing agents, iron chelaters, zinc protoporphyrin-IX, and biological relevant reductants, that might impact on antischistosomal activity induced by interaction of mefloquine with hemin, and preliminary analysis of chemical interaction of both compounds were undertaken. The LC50 and LC95 of mefloquine and hemin alone against schistosomes were determined to be 6.5μg/ml and 7.8μg/ml as well as 232μg/ml and 355μg/ml, respectively. The LC50 and LC95 of mefloquine in the presence of hemin 100μg/ml was 0.24μg/ml and 0.59μg/ml, respectively. On the other hand the LC50 and LC95 of hemin in the presence of mefloquine 1μg/ml was 23.2μg/ml and 77.2μg/ml, respectively. Meanwhile, mefloquine/hemin combinations showed potential synergistic effects against adult S. japonicum, with combination index (CI) values <1. Apart from hemin, zinc protoporphyrin-IX, and other iron providing agents such as ferrous sulfate and ferriammonium sulfate combined with mefloquine exhibited no toxic effect against schistosomes. On the other hand, addition of iron chelators (deferiprone, desferrioxamine mesylate, or 2,2'-bipyridine) to the medium containing mefloquine-hemin resulted in no protective effect on the worms. Furthermore, biological reductants like glutathione, vitamine C or cysteine showed no apparent worm protection effect from toxic mefloquine-hemin even at higher concentrations (242.3-614.6μg/ml, i.e., 6.4-17.8-fold higher than the concentration of hemin). Chemical interaction of mefloquine with hemin was studied in 40% DMSO-Tris buffer solution. Both UV-Vis spectrum and mass spectrum demonstrated the strong interaction of mefloquine with hemin, which resulted in a reduction of hemin color and emergence of an adduct formed by mefloquine

  20. Superhydrophobic surface-based magnetic electrochemical immunoassay for detection of Schistosoma japonicum antibodies.

    PubMed

    Nie, Jinfang; Zhang, Yun; Wang, Hua; Wang, Shiping; Shen, Guoli

    2012-03-15

    In this paper, a magnetic electrochemical immunoassay that uses a superhydrophobic surface-based analytical platform (SSAP) has been initially developed for detection of Schistosoma japonicum (Sj) antibodies (SjAb). The SSAP is fabricated by modifying the inner surfaces of plastic test tubes with superhydrophobic polycarbonate coatings that show a water contact angle up to 160° and a water rolling angle less than 5°. In a noncompetitive sandwich format, the SjAb immunoassay with magnetic particles is based on sensitive stripping voltammetry analysis coupled with the copper enhanced Au nanoparticle tag amplification. This technique is quantitatively sensitive to SjAb concentrations ranging from 2 ng ml(-1) to 15 μg ml(-1), with a detection limit of ∼1.3 ngml(-1). Moreover, the results of assaying several serum specimens prove its feasibility of practical applications. The self-cleaning SSAP can be reused, because no aqueous samples reagents or contaminate the superhydrophobic polycarbonate during the experiments. The comparison study additionally demonstrates that the SSAP-based magnetic electrochemical immunoassays can offer preferable advantages over the existing approaches for SjAb detection, in terms of volumes of samples and reagents, assay time, and detection limit.

  1. Proteomic analysis of tegument-exposed proteins of female and male Schistosoma japonicum worms.

    PubMed

    Zhang, Min; Hong, Yang; Han, Yanhui; Han, Hongxiao; Peng, Jinbiao; Qiu, Chunhui; Yang, Jianmei; Lu, Ke; Fu, Zhiqiang; Lin, Jiaojiao

    2013-11-01

    The interplay between sexes is a prerequisite for female growth, reproductive maturation, and egg production, and the basis of schistosome pathopoiesis and propagation. The tegument is in direct contact with the host environment and its surface membranes are particularly crucial for schistosome survival in the definitive host. In this study, a streptavidin-biotin affinity purification technique combined with LC-MS/MS was used to analyze putative tegument-exposed proteins in female and male adult Schistosoma japonicum worms. In total, 179 proteins were identified in females and 300 in males, including 119 proteins common to both sexes, and 60 female biased and 181 male biased proteins. Some (e.g., serpin and CD36-like class B scavenger receptor) were involved in host-schistosome interactions, while some (e.g., gynecophoral canal protein) were important in the interplay between sexes. Gene Ontology analysis revealed that proteins involved in protein glycosylation and lysosome were highly expressed in females, while proteins involved in intracellular signal transduction, regulation of actin filament polymerization, and proteasome core complex were highly expressed in males. These results might elucidate physiological differences between the sexes. Our study provides new insights into schistosome growth and sexual maturity in the final host and permits the screening of vaccine candidates or drug targets for schistosomiasis.

  2. A Microtus fortis protein, serum albumin, is a novel inhibitor of Schistosoma japonicum schistosomula

    PubMed Central

    Li, Rong; Wu, Guo-Jun; Xiong, De-Hui; Gong, Qiang; Yu, Ruan-Jing; Hu, Wei-Xin

    2013-01-01

    Schistosomiasis is an endemic parasite disease and praziquantel is the only drug currently in use to control this disease. Experimental and epidemiological evidence strongly suggests that Microtus fortis ( Mf ) is a naturally resistant vertebrate host of Schistosoma japonicum . In the present study, we found that Mf serum albumin ( Mf -albumin) and the conditioned medium of pcDNA3.1- Mf -albumin caused 46.2% and 38.7% schistosomula death rates in 96 h, respectively, which were significantly higher than that of the negative control (p < 0.05). We also found that mice injected with Mf -albumin had a 43.5% reduction in worm burden and a 48.1% reduction in liver eggs per gram (p < 0.05) in comparison to the control animals. To characterise the mechanisms involved in clearance, schistosomula were incubated with fluorescein isothiocyanate-labelled Mf -albumin and fluorescent enrichment effects were found in the gut lumen of schistosomula after 48 h of incubation. Next, digestive tract excretions from schistosomula were collected and the sensitivity of Mf -albumin to digestive tract excretions was evaluated. The results indicated that schistosomula digestive tract excretions showed indigestibility of Mf -albumin. The death of schistosomula could be partially attributed to the lack of digestion of Mf -albumin by digestive tract excretions during the development of the schistosomula stage. Therefore, these data indicate the potential of Mf -albumin as one of the major selective forces for schistosomiasis. PMID:24271043

  3. Artemether Treatment of Prepatent Schistosoma japonicum Induces Resistance to Reinfection in Association with Reduced Pathology

    PubMed Central

    Bartley, Paul B.; Glanfield, Amber; Li, Yuesheng; Stanisic, Danielle I.; Duke, Mary; Jones, Malcolm K.; McManus, Donald P.

    2009-01-01

    Artemether (ART) is a well-described antimalarial with efficacy against juvenile schistosomes, with 7-day-old schistosomula being particularly susceptible. Both ART-affected worms and parasites developing from irradiated cercariae die at similar times after infection. Our aim was to determine if ART treatment of prepatent schistosomiasis japonica may result in the generation of a protective immune response. Female CBA mice were treated with a single dose of ART at defined time points after percutaneous infection with a virulent Chinese mainland strain of Schistosoma japonicum. Half of the mouse cohorts were subjected to homologous parasite strain reinfection after drug treatment to assess protective effects of ART therapy. Two independent trials demonstrated that a statistically significant (58% and 50%) reduction in challenge worm burden occurred after reinfection of those mice treated with ART at two weeks p.i. A reduction in the IL-4 response to soluble worm antigen preparation (SWAP) was also seen in ART-treated mice but with no correlation to reinfection resistance. In the Chinese mainland strain used, ART treatment of prepatent infection at the appropriate time point induced resistance to reinfection. There was also an anti-pathology effect observed in ART-treated mice that remained significant after reinfection. PMID:18541772

  4. Kinetic study on the irreversible thermal denaturation of Schistosoma japonicum glutathione S-transferase.

    PubMed

    Quesada-Soriano, Indalecio; García-Maroto, Federico; García-Fuentes, Luis

    2006-05-01

    The thermal unfolding pathway of the Schistosoma japonicum glutathione S-transferase (Sj26GST) was previously interpreted by applying equilibrium thermodynamics and a reversible two-state model (Kaplan et al., (1997) Protein Science, 6, 399-406), though weak support for this interpretation was provided. In our study, thermal denaturation of Sj26GST has been re-examined by differential scanning calorimetry in the pH range of 6.5-8.5 and in the presence of the substrate and S-hexylglutathione. Calorimetric traces were found to be irreversible and highly scan-rate dependent. Thermogram shapes, as well as their scan-rate dependence, can be globally explained by assuming that thermal denaturation takes place according to one irreversible step described by a first-order kinetic constant that changes with temperature, as given by an Arrhenius equation. On the basis of this model, values for the rate constant as a function of temperature and the activation energy have been determined. Data also indicate that binding of GSH or S-hexylglutathione just exert a very little stabilising effect on the dimeric structure of the molecule.

  5. Dynamics of Th17 Cells and Their Role in Schistosoma japonicum Infection in C57BL/6 Mice

    PubMed Central

    Chi, Ying; Zhou, Sha; Hoellwarth, Jason; Zhang, Cui; Zhu, Jifeng; Wu, Calvin; Dhesi, Shawn; Wang, Xuefeng; Liu, Feng; Su, Chuan

    2011-01-01

    Background The current knowledge of immunological responses to schistosomiasis, a major tropical helminthic disease, is insufficient, and a better understanding of these responses would support vaccine development or therapies to control granuloma-associated immunopathology. CD4+ T cells play critical roles in both host immune responses against parasitic infection and immunopathology in schistosomiasis. The induction of T helper (Th)1, Th2 and T regulatory (Treg) cells and their roles in schistosome infections are well-illustrated. However, little in vivo data are available on the dynamics of Th17 cells, another important CD4+ T cell subset, after Schistosoma japonicum infection or whether these cells and their defining IL-17 cytokine mediate host protective responses early in infection. Methodology Levels of Th17 and the other three CD4+ T cell subpopulations and the cytokines related to induction or repression of Th17 cell generation in different stages of S. japonicum infection were observed. Contrary to reported in vitro studies, our results showed that the Th17 cells were induced along with the Th1, Th2, Treg cells and the IFN-γ and IL-4 cytokines in S. japonicum infected mice. The results also suggested that S. japonicum egg antigens but not adult worm antigens preferentially induced Th17 cell generation. Furthermore, decreasing IL-17 with a neutralizing anti-IL-17 monoclonal antibody (mAb) increased schistosome-specific antibody levels and partial protection against S. japonicum infection in mice. Conclusions Our study is the first to report the dynamics of Th17 cells during S. japonicum infection and indicate that Th17 cell differentiation results from the integrated impact of inducing and suppressive factors promoted by the parasite. Importantly, our findings suggest that lower IL-17 levels may result in favorable host protective responses. This study significantly contributes to the understanding of immunity to schistosomiasis and may aid in developing

  6. The Sensitivity of Schistosoma japonicum to Praziquantel: A Field Evaluation in Areas with Low Endemicity of China

    PubMed Central

    Wang, Wei; Dai, Jian-Rong; Li, Hong-Jun; Shen, Xue-Hui; Liang, You-Sheng

    2012-01-01

    The purpose of the current study was to investigate the susceptibility of Schistosoma japonicum to praziquantel in low endemic foci of China. During the non-transmission period of schistosomiasis, a total of 43 of 1,242 subjects were identified as being infected with the parasite using parasitological stool examinations in two low-endemicity areas of China, with a prevalence rate of 3.46%. All stool-egg-positive subjects were treated with praziquantel in a single oral dose of 40 mg/kg or 30 mg/kg for two successive days. Six weeks post-treatment, no S. japonicum eggs were detected in the 43 treated villagers. The results indicate that the current efficacy of praziquantel against S. japonicum seems satisfactory and has not changed over the past three decades in the low endemic areas of China. It is also suggested that no evidence of tolerance or resistance to praziquantel in S. japonicum is detected in areas with low endemicity in China. PMID:22556083

  7. Whole Genome Amplification and Reduced-Representation Genome Sequencing of Schistosoma japonicum Miracidia

    PubMed Central

    Shortt, Jonathan A.; Card, Daren C.; Schield, Drew R.; Liu, Yang; Zhong, Bo; Castoe, Todd A.

    2017-01-01

    Background In areas where schistosomiasis control programs have been implemented, morbidity and prevalence have been greatly reduced. However, to sustain these reductions and move towards interruption of transmission, new tools for disease surveillance are needed. Genomic methods have the potential to help trace the sources of new infections, and allow us to monitor drug resistance. Large-scale genotyping efforts for schistosome species have been hindered by cost, limited numbers of established target loci, and the small amount of DNA obtained from miracidia, the life stage most readily acquired from humans. Here, we present a method using next generation sequencing to provide high-resolution genomic data from S. japonicum for population-based studies. Methodology/Principal Findings We applied whole genome amplification followed by double digest restriction site associated DNA sequencing (ddRADseq) to individual S. japonicum miracidia preserved on Whatman FTA cards. We found that we could effectively and consistently survey hundreds of thousands of variants from 10,000 to 30,000 loci from archived miracidia as old as six years. An analysis of variation from eight miracidia obtained from three hosts in two villages in Sichuan showed clear population structuring by village and host even within this limited sample. Conclusions/Significance This high-resolution sequencing approach yields three orders of magnitude more information than microsatellite genotyping methods that have been employed over the last decade, creating the potential to answer detailed questions about the sources of human infections and to monitor drug resistance. Costs per sample range from $50-$200, depending on the amount of sequence information desired, and we expect these costs can be reduced further given continued reductions in sequencing costs, improvement of protocols, and parallelization. This approach provides new promise for using modern genome-scale sampling to S. japonicum surveillance

  8. High-throughput dynamic analysis of differentially expressed genes in splenic dendritic cells from mice infected with Schistosoma japonicum.

    PubMed

    Chen, Lin; Chen, Qingzhou; Hou, Wei; He, Li

    2017-04-01

    Dendritic cells are the initiation and key point of immune response and play a role in immune regulation. So we explored the mechanisms involved in immune regulation of dendritic cells (DCs) against schistosomiasis using mice infected with Schistosoma japonicum. Splenic DCs from normal mice and mice with acute and chronic S. japonicum infection were sorted by flow cytometry. The numbers and functions of differentially expressed genes (DEGs) in DCs were determined by high-throughput analysis. All DEGs with transcription-level fold changes of ≥2 were selected and matched to corresponding genes in databases. Annotations and cluster analysis of DEGs were performed to compare differences between groups. Six important DEGs about immune regulation-CD86, TLR2, DC-SIGN, Capase3, PD-L2, and IL-7r were selected, and their transcription levels at different stages of schistosomisis were validated by qPCR. The Venn diagram of DEGs implied some genes are functional at all stages during S. japonicum infection, while others are only involved at certain stages. GO and KEGG pathway annotations indicated that these DEGs mainly belong to biological regulation, regulation of biological process, regulation of cellular process, antigen processing and presentation, cell adhesion molecules, cytokine-cytokine receptor interaction and Toll-like receptor signaling. Cluster analysis revealed immune regulation existed in splenic DCs. The results above indicated that the mechanisms underlying immune regulation to S. japonicum infection in mice are very complex. The present high-throughput dynamic analysis of DEGs in splenic DCs provides valuable insights into the molecular mechanisms underlying immune regulation in S. japonicum infection. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  9. In vitro maintenance of Schistosoma japonicum and surgical transfer from donor to naïve recipient pigs.

    PubMed

    Schou, T W; Bøgh, H O; Willingham, A L; Brück, I; Nielsen, C G; Sørensen, E; Eriksen, L; Andreassen, J

    1997-12-15

    An objective of this study was to find a culture medium and a temperature range suitable for in vitro maintenance of adult Schistosoma japonicum during surgical transplantation experiments. Adult S. japonicum were cultivated in four different media (NCTC 135, NCTC 109, RPMI 1640 and 0.85% physiological saline) supplemented with 10% heat-inactivated normal pig serum (hiNPS) at either 4 degrees C, 22-25 degrees C (room temperature) or 37 degrees C. Based on survival and morphologic evaluation, NCTC 135 at room temperature was found to be the best medium/temperature combination for maintenance of worms. An additional objective was to develop a method for transplanting adult S. japonicum from experimentally infected donor pigs to naïve recipient pigs. Six Landrace/Yorkshire crossbred pigs were used as donors to supply worms for two recipient pigs. Worms for transplantation were obtained by perfusion of the mesenteric veins of the donor pigs and maintained for a maximum of 3 h in NCTC 135 + 10% hiNPS at room temperature. A total of 148 and 132 worms were surgically transferred by way of an infusion tube into caecal veins of the two recipients. Six weeks after transplantation, 14% and 36% of the transferred worms were recovered by perfusion and subsequent manual inspection of the mesenteric veins of the two recipient pigs, respectively. The successful results suggest that surgical transfer of S. japonicum worms from donor to naïve recipient pigs may be useful for future studies on population genetics, dynamics and regulation in the pig/S. japonicum model.

  10. Maternal Infection with Schistosoma japonicum Induces a Profibrotic Response in Neonates

    PubMed Central

    Cheng, Ling; Jarilla, Blanca; Sagliba, Marianne J.; Gonzal, Annaliza; Amoylen, Amabelle J.; Olveda, Remigio; Acosta, Luz; Baylink, David; White, Eric S.; Friedman, Jennifer F.; Kurtis, Jonathan D.

    2014-01-01

    The global burden of schistosomiasis is significant, with fibrosis a major associated morbidity and the primary cause of mortality. We have previously shown that schistosomiasis during pregnancy upregulates proinflammatory cytokines in the cord blood. In this study, we extend these findings to include a large panel of fibrosis-associated markers. We developed a multiplex bead-based assay to measure the levels of 35 proteins associated with fibrosis. Cord blood from 109 neonates born to mothers residing in an area of Schistosoma japonicum endemicity was assessed for these molecules. Ten mediators were elevated in the cord blood from schistosome-infected pregnancies, including insulin-like growth factor 1 (IGF-1), tumor growth factor β1 (TGF-β1), connective tissue growth factor (CTGF), procollagen I carboxy-terminal propeptide (PICP), amino-telopeptide of type 1 collagen (ICTP), collagen VI, desmosine, matrix metalloproteinase 2 (MMP-2), tissue inhibitor of metalloproteinases 1 (TIMP-1), and TIMP-4. Many of these were also positively correlated with preterm birth (PICP, ICTP, MMP-2, TGF-β1, desmosine, CTGF, TIMP-1). In addition, birth weight was 168 g lower for infants with detectable levels of CTGF than for those with CTGF levels below the level of detection. Maternal schistosomiasis results in upregulation of fibrosis-associated proteins in the cord blood of the neonate, a subset of which are also associated with adverse birth outcomes. As the first report of fibrosis-associated molecules altered in the newborn of infected mothers, this study has broad implications for the health of the fetus, stretching from gestation to adulthood. PMID:24166958

  11. [Distribution of niclosamide spreading oil on water surface and its efficacy against cercariae of Schistosoma japonicum].

    PubMed

    Xing, Yun-Tian; Dai, Yang; Li, You-Zi; Jia, Yue; Li, Hong-Jun; Qu, Guo-Li; Wang, Wei; Wei, Jian-Ying; Liang, You-Sheng; Dai, Jian-Rong

    2012-08-01

    To investigate the distribution and spreading speed of niclosamide spreading oil, as well as its effect against cercariae of Schistosoma japonicum. The foamed plastic with a diameter of 4 mm served as a buoyage, which was placed at the center of the still water surface. The niclosamide spreading oil was dropped at 0.5 cm from the buoyage, the floating distance of the buoyage was observed, and the spreading speed and area of the niclosamide spreading oil were measured. A cylindrical bucket (at a diameter of 40 cm and height of 50 cm) was filled with de-chlorinated water at a temperature of 25 +/- 1 degrees C, and then 60 microl of the spreading oil was dropped at the center of the water surface. At 10 cm and 20 cm from the center, 1 ml water was sampled at water depths of 10, 20, 30, 40 cm and 50 cm, respectively, and the niclosamide concentrations were determined by using high-performance liquid chromatography in each sample. The niclosamide spreading oil was diluted into solutions at effective concentrations of 1.25 mg/L and 0.63 mg/L with ethanol, and then 10 microl of each solution was added to 24-well plates which contained S. japonicum cercariae to yield the niclosamide concentration of 6.25 x 10(-3) mg/L and 3.13 x 10(-3) mg/L per well, respectively. The survival of the cercariae was observed at different time. The spreading speeds and areas were 59, 55, 71, 90, 111, 122 cm/s and 153 cm/s, and 5.31, 5.89, 7.07, 10.06, 12.56, 15.20 m2 and 16.61 m2, respectively, while dropping 20, 30, 40, 50, 60, 70 microl and 80 microl of the niclosamide spreading oil on water surface. The spreading showed an accelerating trend with the increasing dropping volume, and there was a good linear relationship observed between them. In addition, the spreading area also enlarged with the increase in the dropping volume. After dropping 60 microl of the niclosamide spreading oil on water surface, the peak concentration of niclosamide reached 1.27 mg/L on water surface, and remained

  12. SjTat-TPI facilitates adaptive T-cell responses and reduces hepatic pathology during Schistosoma japonicum infection in BALB/c mice.

    PubMed

    Zhang, Wenyue; Luo, Xiaofeng; Zhang, Fan; Zhu, Yuxiao; Yang, Bingya; Hou, Min; Xu, Zhipeng; Yu, Chuanxin; Chen, Yingying; Chen, Lin; Ji, Minjun

    2015-12-30

    Schistosomiasis is a kind of parasitic zoonoses which causes serious damage to public health and social development. China is one of the countries most affected by Schistosoma japonicum and an effective vaccine is still needed. In this study, we adopted Tat-mediated protein transduction technology to investigate the impact of different antigen presented approaches on host's immune response and the potential protection against Schistosoma japonicum infection. We successfully constructed the recombinant S. japonicum triosephosphate isomerase, Tat-TPI, as a vaccine candidate. Whether injected with Tat-TPI in foot pad or vaccinated with Tat-TPI in the back subcutaneously for three times, the draining popliteal lymph nodes and spleen both developed a stronger CD8(+)T response (Tc1) in mice. Not only that, but it also helped CD4(+)T cells to produce more IFN-γ than TPI immunisation. In addition, it could boost IgG production, especially IgG1 subclass. Most importantly, Tat-TPI immunisation led to the significant smaller area of a single egg granuloma in the livers as compared with TPI-vaccinated or control groups. However, the anti-infection efficiency induced by Tat-TPI was still restricted. This study indicated that immunisation with Tat-fused TPI could contribute to enhance CD4(+)T-cell response and decrease hepatic egg granulomatous area after S. japonicum infection though it did not achieve our expected protection against Schistosoma japonicum infection. The optimal vaccine strategy warrants further research.

  13. Aldose reductase from Schistosoma japonicum: crystallization and structure-based inhibitor screening for discovering antischistosomal lead compounds

    PubMed Central

    2013-01-01

    Background Schistosomiasis is a neglected tropical disease with high morbidity and mortality in the world. Currently, the treatment of this disease depends almost exclusively on praziquantel (PZQ); however, the emergence of drug resistance to PZQ in schistosomes makes the development of novel drugs an urgent task. Aldose reductase (AR), an important component that may be involved in the schistosome antioxidant defense system, is predicted as a potential drug target. Methods The tertiary structure of Schistosoma japonicum AR (SjAR) was obtained through X-ray diffraction method and then its potential inhibitors were identified from the Maybridge HitFinder library by virtual screening based on this structural model. The effects of these identified compounds on cultured adult worms were evaluated by observing mobility, morphological changes and mortality. To verify that SjAR was indeed the target of these identified compounds, their effects on recombinant SjAR (rSjAR) enzymatic activity were assessed. The cytotoxicity analysis was performed with three types of human cell lines using a Cell Counting Kit-8. Results We firstly resolved the SjAR structure and identified 10 potential inhibitors based on this structural model. Further in vitro experiments showed that one of the compounds, renamed as AR9, exhibited significant inhibition in the activity of cultured worms as well as inhibition of enzymatic activity of rSjAR protein. Cytotoxicity analysis revealed that AR9 had relatively low toxicity towards host cells. Conclusions The work presented here bridges the gap between virtual screening and experimental validation, providing an effective and economical strategy for the development of new anti-parasitic drugs. Additionally, this study also found that AR9 may become a new potential lead compound for developing novel antischistosomal drugs against parasite AR. PMID:23734964

  14. Effect of photoperiod change on chronobiology of cercarial emergence of Schistosoma japonicum derived from hilly and marshy regions of China.

    PubMed

    Wang, Su-Rong; Zhu, Yuan-Jian; Ge, Qing-Peng; Yang, Meng-Jia; Huang, Ji-Lei; Huang, Wen-Qiao; Zhuge, Hong-Xiang; Lu, Da-Bing

    2015-12-01

    The chronobiology of cercarial emergence appeared to be a genetically controlled behavior, adapted to definitive host species, for schistosome. However, a few physiological and ecological factors, for example the change of photoperiod, were reported to affect the rhythmic emergence of cercariae. Therefore, the effect of photoperiod change on cercarial emergence of two Schistosoma japonicum isolates, the hilly and the marshland, was investigated. Four shedding experiments each under a different photoperiod were conducted. Under a natural photoperiod, two distinct shedding modes, one from the hilly region and one from the marshland, were observed. Under a reversed photoperiod, the regular pattern (i.e. under a natural photoperiod) of S. japonicum cercarial emergence was reversed for the marshland isolate and disappeared for the hilly isolate. With an input of a 2 h darkness from 7am to 9am, the cercarial emergence peak were delayed for the two isolates; whereas with an input of a 2 h darkness from 5pm to 7pm, neither effect on the cercarial emergence rhythm was observed. The total cercariae emerged for both parasite isolates varied with a different photoperiod. The results indicate that the change of photoperiod could affect the chronobiology of S japonicum cercarial emergence.

  15. Combined TLR7/8 and TLR9 Ligands Potentiate the Activity of a Schistosoma japonicum DNA Vaccine

    PubMed Central

    Wang, Xuefeng; Dong, Liyang; Ni, Hongchang; Zhou, Sha; Xu, Zhipeng; Hoellwarth, Jason Shih; Chen, Xiaojun; Zhang, Rongbo; Chen, Qiaoyun; Liu, Feng; Wang, Jun; Su, Chuan

    2013-01-01

    Background Toll-like receptor (TLR) ligands have been explored as vaccine adjuvants for tumor and virus immunotherapy, but few TLR ligands affecting schistosoma vaccines have been characterized. Previously, we developed a partially protective DNA vaccine encoding the 26-kDa glutathione S-transferase of Schistosoma japonicum (pVAX1-Sj26GST). Methodology/Principal Findings In this study, we evaluated a TLR7/8 ligand (R848) and a TLR9 ligand (CpG oligodeoxynucleotides, or CpG) as adjuvants for pVAX1-Sj26GST and assessed their effects on the immune system and protection against S. japonicum. We show that combining CpG and R848 with pVAX1-Sj26GST immunization significantly increases splenocyte proliferation and IgG and IgG2a levels, decreases CD4+CD25+Foxp3+ regulatory T cells (Treg) frequency in vivo, and enhances protection against S. japonicum. CpG and R848 inhibited Treg-mediated immunosuppression, upregulated the production of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-10, IL-2, and IL-6, and decreased Foxp3 expression in vitro, which may contribute to prevent Treg suppression and conversion during vaccination and allow expansion of antigen-specific T cells against pathogens. Conclusions Our data shows that selective TLR ligands can increase the protective efficacy of DNA vaccines against schistosomiasis, potentially through combined antagonism of Treg-mediated immunosuppression and conversion. PMID:23593527

  16. Genetic variation between Schistosoma japonicum lineages from lake and mountainous regions in China revealed by resequencing whole genomes.

    PubMed

    Yin, Mingbo; Liu, Xiao; Xu, Bin; Huang, Jian; Zheng, Qi; Yang, Zhong; Feng, Zheng; Han, Ze-Guang; Hu, Wei

    2016-09-01

    Schistosoma infection is a major cause of morbidity and mortality worldwide. Schistosomiasis japonica is endemic in mainland China along the Yangtze River, typically distributed in two geographical categories of lake and mountainous regions. Study on schistosome genetic diversity is of interest in respect of understanding parasite biology and transmission, and formulating control strategy. Certain genetic variations may be associated with adaptations to different ecological habitats. The aim of this study is to gain insight into Schistosoma japonicum genetic variation, evolutionary origin and associated causes of different geographic lineages through examining homozygous Single Nucleotide Polymorphisms (SNPs) based on resequenced genome data. We collected S. japonicum samples from four sites, three in the lake regions (LR) of mid-east (Guichi and Tonglin in Anhui province, Laogang in Hunan province) and one in mountainous region (MR) (Xichang in Sichuan province) of south-west of China, resequenced their genomes using Next Generation Sequencing (NGS) technology, and made use of the available database of S. japonicum draft genomic sequence as a reference in genome mapping. A total of 14,575 SNPs from 2059 genes were identified in the four lineages. Phylogenetic analysis confirmed significant genetic variation exhibited between the different geographical lineages, and further revealed that the MR Xichang lineage is phylogenetically closer to LR Guich lineage than to other two LR lineages, and the MR lineage might be evolved from LR lineages. More than two thirds of detected SNPs were nonsynonymous; functional annotation of the SNP-containing genes showed that they are involved mainly in biological processes such as signaling and response to stimuli. Notably, unique nonsynonymous SNP variations were detected in 66 genes of MR lineage, inferring possible genetic adaption to mountainous ecological condition.

  17. Antibody isotype responses to paramyosin, a vaccine candidate for schistosomiasis, and their correlations with resistance and fibrosis in patients infected with Schistosoma japonicum in Leyte, The Philippines.

    PubMed

    Nara, Takeshi; Iizumi, Kyoichi; Ohmae, Hiroshi; Sy, Orlando S; Tsubota, Soichi; Inaba, Yutaka; Tsubouchi, Akiko; Tanabe, Masanobu; Kojima, Somei; Aoki, Takashi

    2007-02-01

    We examined whether antibody isotype responses to paramyosin (PM), a vaccine candidate for schistosomiasis, are associated with age-dependent resistance and pathology in liver fibrosis using human sera collected from 139 individuals infected with Schistosoma japonicum in Leyte, The Philippines. We report that IgA and IgG3 responses to PM showed a positive correlation with age and that the epitopes responsible were localized predominantly within the N-terminal half of PM. In addition, the IgG3 response to PM was associated with serum level of procollagen-III-peptide (P-III-P), an indicator of progression of liver fibrosis. These results imply that IgG3 against PM may not only provoke age-dependent resistance to S. japonicum infection but also enhance liver fibrosis. In contrast, levels of IgE to PM and to multiple PM fragments showed a negative correlation with P-III-P level. Thus, in contrast to IgG3, increases in PM-specific IgE may contribute to suppression of liver pathogenesis in schistosomiasis.

  18. Phosphagen kinase in Schistosoma japonicum: characterization of its enzymatic properties and determination of its gene structure.

    PubMed

    Tokuhiro, Shinji; Uda, Kouji; Yano, Hiroko; Nagataki, Mitsuru; Jarilla, Blanca R; Suzuki, Tomohiko; Agatsuma, Takeshi

    2013-04-01

    Phosphagen kinases (PKs) play a major role in the regulation of energy metabolism in animals. Creatine kinase (CK) is the sole PK in vertebrates, whereas several PKs are present in invertebrates. Here, we report the enzymatic properties and gene structure of PK in the trematode Schistosoma japonicum (Sj). SjPK has a unique contiguous dimeric structure comprising domain 1 (D1) and domain 2 (D2). The three states of the recombinant SjPK (D1, D2, and D1D2) show a specific activity for the substrate taurocyamine. The comparison of the two domains of SjPK revealed that D1 had a high turnover rate (kcat=52.91) and D2 exhibited a high affinity for taurocyamine (Km(Tauro) =0.53±0.06). The full-length protein exhibited higher affinity for taurocyamine (Km(Tauro) =0.47±0.03) than the truncated domains (D1=1.30±0.10, D2=0.53±0.06). D1D2 also exhibited higher catalytic efficiency (kcat/Km(Tauro) =82.98) than D1 (40.70) and D2 (29.04). These results demonstrated that both domains of SjTKD1D2 interacted efficiently and remained functional. The three-dimensional structure of SjPKD1 was constructed by the homology modeling based on the transition state analog complex state of Limulus AK. This protein model of SjPKD1 suggests that the overall structure is almost conserve between SjPKD1 and Limulus AK except for the flexible loops, that is, particularly guanidino-specificity (GS) region, which is associated with the recognition of the corresponding guanidino substrate. The constructed NJ tree and the comparison of exon/intron organization suggest that SjTK has evolved from an arginine kinase (AK) gene. SjTK has potential as a novel antihelminthic drug target as it is absent in mammals and its strong activity may imply a significant role for this protein in the energy metabolism of the parasite. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. The anterior esophageal region of Schistosoma japonicum is a secretory organ.

    PubMed

    Li, Xiao Hong; Stark, Meg; Vance, Gillian M; Cao, Jian Ping; Wilson, R Alan

    2014-12-10

    The esophagus of blood-feeding schistosomes has been largely neglected although its posterior portion was designated as a gland decades ago. However, we recently showed it plays a pivotal role in blood processing. It is clearly demarcated into anterior and posterior compartments, both surrounded by a mass of cell bodies. Feeding movies revealed that erythrocytes accumulate in the anterior compartment before entering the posterior, indicating that a distinct process is executed there. We therefore investigated ultrastructural aspects and possible functions of the anterior region. The heads of adult Schistosoma japonicum were detached and prepared for both transmission and scanning electron microscopy to define the detailed ultrastructure of the anterior esophagus. Cryosections of heads were also prepared for immunocytochemistry and confocal microscopy to define the pattern of intrinsic host antibody binding in the anterior esophageal lining. The anterior syncytial lining of the esophagus is highly extended by long, thin corrugations of cytoplasm projecting towards the lumen. Strikingly in the male worm, the tips of the corrugations are further expanded by numerous threads of cytoplasm, producing a spaghetti-like appearance in the central lumen. Flattened, pitted cytoplasmic plates are interspersed in the tangled mass of threads. Abundant, morphologically distinct light vesicles of varied size and contents are manufactured in the cell bodies, from where they traffic through cytoplasmic connections to the corrugations and out to the tips. Clusters of vesicles accumulate in expanded tips in males, together with occasional mitochondria whilst females have more mitochondria but fewer vesicles. The membranous contents of light vesicles are secreted mainly from the tips, but also from the sides of the corrugations. They coat the surfaces and then form organised self-adherent membrane figures when shed into the lumen. Host antibody binds strongly in a characteristic pattern

  20. Genetic diversity and structure of Schistosoma japonicum within two marshland villages of Anhui, China, prior to schistosome transmission control and elimination.

    PubMed

    Ding, Huan; Lu, Da-Bing; Gao, Yu-Meng; Deng, Yao; Li, Ying

    2017-02-01

    Schistosomiasis is caused by the genus Schistosoma and affected more than 250 million people worldwide. Schistosoma japonicum was once seriously endemic in China and nearly 60 years of efforts has seen great success in disease control. However, due to its zoonotic nature and complex life cycle, the schistosomiasis transmission control and final elimination would require, besides an intersectoral approach, deep understanding of population genetics of the parasite. We therefore performed a snail survey in two marshland villages of Anhui province of China and collected S. japonicum cercariae from infected snails. By using the recent developed microsatellite panel comprising seven loci, we genotyped the sampled parasites and analyzed the population genetic diversity and structure. The results showed much lower infection prevalence of S. japonicum in snails and low infected snail density in either marshland village. Through population genetic analyses, a considerable genetic diversity of parasites was revealed, whereas a small number of clusters were inferred and the sign of bottleneck effect was detected in each village. For the first time in S. japonicum in two villages, we provided estimates of effective population sizes with two different approaches. The results indicated that the parasite in two villages could eventually be eradicated with the ongoing integral control measures, but with potential risk of reinvasion of immigrant parasites through the Yangtze River. Such would be of great importance in assessment of the effects of ongoing control measures and prediction of the transmission capability for S. japonicum, thus guiding decisions on the choice of further control work.

  1. Specific anti-glycan antibodies are sustained during and after parasite clearance in Schistosoma japonicum-infected rhesus macaques

    PubMed Central

    Yang, Y. Y. Michelle; Li, Xiao Hong; Brzezicka, Katarzyna; Reichardt, Niels-Christian; Wilson, R. Alan; van Diepen, Angela

    2017-01-01

    Background Human immunity to Schistosoma infection requires many years of exposure, and multiple infections and treatments to develop. Unlike humans, rhesus macaques clear an established schistosome infection naturally at the same time acquiring immunity towards re-infection. In macaques, schistosome egg production decreases after 8 weeks post-infection and by week 22, physiological impairment of the worm caused by unclarified antibody-mediated processes is observed. Since strong antibody responses have been observed against schistosome glycan antigens in human and animal infections, we here investigate if anti-glycan antibodies are associated with immunity against schistosome infections in macaques. Methods We used a microarray containing a large repertoire of glycoprotein- and glycolipid-derived glycans from different schistosome life stages to analyse anti-glycan serum IgG and IgM from S. japonicum-infected macaques during the course of infection and self-cure. We also used an in vitro schistosomula assay to investigate whether macaque sera containing anti-glycan antibodies can kill schistosomula. Conclusions/significance Antibody responses towards schistosome glycans at week 4 post-infection were dominated by IgM while IgG was high at week 8. The profound increase in IgG was observed mainly for antibodies towards a large subset of glycans that contain (multi-)fucosylated terminal GalNAcβ1-4GlcNAc (LDN), and Galβ1-4(Fucα1–3)GlcNAc (LeX) motifs. In general, glycans with a higher degree of fucosylation gave rise to stronger antibody responses than non-fucosylated glycans. Interestingly, even though many IgG and IgM responses had declined by week 22 post-infection, IgG towards O-glycans with highly fucosylated LDN motifs remained. When incubating macaque serum with schistosomula in vitro, schistosomula death was positively correlated with the duration of infection of macaques; macaque serum taken 22 weeks post-infection caused most schistosomula to die

  2. Dynamic transcriptomes identify biogenic amines and insect-like hormonal regulation for mediating reproduction in Schistosoma japonicum.

    PubMed

    Wang, Jipeng; Yu, Ying; Shen, Haimo; Qing, Tao; Zheng, Yuanting; Li, Qing; Mo, Xiaojin; Wang, Shuqi; Li, Nana; Chai, Riyi; Xu, Bin; Liu, Mu; Brindley, Paul J; McManus, Donald P; Feng, Zheng; Shi, Leming; Hu, Wei

    2017-03-13

    Eggs produced by the mature female parasite are responsible for the pathogenesis and transmission of schistosomiasis. Female schistosomes rely on a unique male-induced strategy to accomplish reproductive development, a process that is incompletely understood. Here we map detailed transcriptomic profiles of male and female Schistosoma japonicum across eight time points throughout the sexual developmental process from pairing to maturation. The dynamic gene expression pattern data reveal clear sex-related characteristics, indicative of an unambiguous functional division between males and females during their interplay. Cluster analysis, in situ hybridization and RNAi assays indicate that males likely use biogenic amine neurotransmitters through the nervous system to control and maintain pairing with females. In addition, the analyses indicate that reproductive development of females involves an insect-like hormonal regulation. These data sets and analyses serve as a foundation for deeper study of sexual development in this pathogen and identification of novel anti-schistosomal interventions.

  3. Control Efficacy of Annual Community-Wide Treatment against Schistosoma japonicum in China: A Meta-Analysis

    PubMed Central

    Su, Jing; Lu, Da-Bing; Zhou, Xia; Wang, Su-Rong; Zhuge, Hong-Xiang

    2013-01-01

    Backgrounds Human schistosomiasis is caused by schistosome, with annual loss of over 70 million disability adjusted life years in the world. China is endemic with Schistosoma japonicum and large-scale chemotherapy with praziquantel has become the mainstay of control in China since 1990s. However, the control effects of mass treatment in the field have been uneven. Moreover, mass treatment has come into a wide use in other countries with limited health resources. Therefore, a better understanding of the control effect of mass treatment is in an urgent need. Methods We performed a systematic search of the literature to investigate the control efficiency of annual community-wide treatment (ACWT, treatment to an entire community without any preliminary screening) with a single dose of PZQ (40 mg kg−1 bodyweight) against schistosome in humans in China. Three Chinese literature databases, including China National Knowledge Infrastructure, WanFang and Chinese Scientific Journal Databases, and the PubMed were searched. Pooled prevalence ratios (prevalence after to before treatment) were used to assess effect. Our protocol is available on PROSPERO (No. CRD42013003628). Results 22 articles were included. Meta-analyses on data from 18 studies on one round of ACWT, 17 studies on two consecutive rounds and 6 studies on three consecutive rounds were performed. The results showed control effects of ACWT plus other measures were statistically significant, with prevalence ratios being 0.38 (0.31, 0.46) for one round, 0.28 (0.22, 0.35) for two rounds and 0.22 (0.10, 0.46) for three rounds. When ACWT was performed alone or with health education only, the values for one and two rounds were 0.389 (0.307, 0.492) and 0.348 (0.300, 0.403), respectively. Conclusions The control effect of ACWT alone or with other measures is significant and increases with the number of rounds. Such program is recommended in high endemic areas and the criteria yet merit further assessment. PMID:24223819

  4. An investigation into the potential effects of infrapopulation structure and other sources of sampling error, on population genetic studies of the transmission of Schistosoma japonicum (Trematoda: Digenea).

    PubMed

    Huo, Guan-Nan; Liu, Liang; He, Hong-Bin; Attwood, Stephen W

    2016-03-21

    Schistosoma japonicum remains a major challenge to human and animal health. Earlier microsatellite-based studies reported possible definitive-host-specific private alleles within S. japonicum, opening the possibility that different definitive hosts might harbour different parasite strains. Previous investigations have also detected near-identical multilocus genotypes in populations of adult worms - possibly the result of mutations occurring during the asexual (intramolluscan) phase of clonal expansion. Research has also revealed extensive deviations from Hardy-Weinberg Proportions (HWP) and conflicting results among studies. The present study was performed to examine some of the potential effects of infrapopulation structure on microsatellite-based studies of the transmission ecology of S. japonicum. Potential sources of bias considered included organotropic distribution of worms, non-random mating and corrections for clonal expansion. Stool samples from naturally infected hosts were used to infect snails in the laboratory and thereby expose mice. 274 individual worms were typed at seven microsatellite loci. Removal of individuals bearing duplicate MLGs (as a correction for presumed clonal expansion) had an impact on both HWP and organotropic genetic differentiation. The study found no evidence that heterozygote deficiencies were caused by a Wahlund effect. Female-male pairings appeared to be random and there was no evidence for mate choice by heterozygosity. There was some indication that excess heterozygosity, induced by clonal expansion, can offset heterozygote deficiencies caused by small population size or populations fragmented by parasite control efforts. The view is supported that miracidia are preferable to adult worms in investigations into host-specific parasite lineages. Where adults must be used, extreme care should be taken with regard to sampling if infrapopulations of small animals are compared with those of larger animals; this is because of

  5. Single- or mixed-sex Schistosoma japonicum infections of intermediate host snails in hilly areas of Anhui, China.

    PubMed

    Shi, Hui-Ping; Lu, Da-Bing; Shen, Lei; Shi, Tan; Gu, Jian

    2014-02-01

    Schistosomiasis japonicum is one of the most serious communicable diseases, and the transmission of the parasite is dependent of its complex life cycle on which many factors can have an impact. Multiple infections comprising both male and female schistosome within snail intermediate hosts, for example, would facilitate parasite transmission. However, no research on Schistosoma japonicum communities in field-collected Oncomelania hupensis hupensis in relation to schistosome sex has been reported. Therefore, snail survey was performed in a hilly region of Anhui, China, and single- or mixed-sex schistosome infections of snails were detected with final host mouse infection. A total of 8,563 snails were sampled in the field, and 67 were identified with schistosome infections. Of these infected snails, 46 were selected for final host infection. From this, 21 snails were infected with female schistosome, 23 with males and 2 with both males and females. More worms were recovered for snails with mixed-sex infections than with single-sex infection and for snails with male schistosome infection than with female infection (P<0.001). The observed frequency of mixed-sex infections of snails was significantly higher than would be expected if randomly distributed (P<0.01). The ratio male/female of schistosome infections in snails was nearly equal and up to 95.65 % (44/46) of infected snails were single-sex infection. Schistosome infections in snails collected from the hilly area of Anhui Province were not randomly distributed but over-dispersed.

  6. Variable maturation and oviposition by female Schistosoma japonicum in mice: the effects of irradiation of the host prior to infection

    SciTech Connect

    Cheever, A.W.; Duvall, R.H.

    1987-11-01

    The maturation of female Schistosoma japonicum was found to vary greatly within each of two Philippine strains of this parasite and some females did not contain uterine eggs 7 to 15 weeks after infection while others contained numerous eggs before the fifth week of infection. It was found that female worms containing less than 20 uterine eggs contributed little to the accumulation of eggs in the tissues of infected mice. Such worms also generally appeared to be immature. The variable rate of maturation of worms is likely to have profound effects on the immune reactions of mice as well as on the pathologic response to infection. Systematic delay in oviposition was serendipitously found in worms from mice which had been irradiated for other purposes prior to exposure to S. japonicum, and from the fourth to the sixth week after infection egg production by worms in irradiated mice lagged well behind that in intact mice. Seven to 10 weeks after infection these worms were laying normal numbers of eggs, as judged by egg passage per worm pair in the feces and the accumulation of eggs in the tissues. S. mansoni developed normally in irradiated mice.

  7. iTRAQ-based comparative proteomic analysis of excretory-secretory proteins of schistosomula and adult worms of Schistosoma japonicum.

    PubMed

    Cao, Xiaodan; Fu, Zhiqiang; Zhang, Min; Han, Yanhui; Han, Hongxiao; Han, Qian; Lu, Ke; Hong, Yang; Lin, Jiaojiao

    2016-04-14

    Schistosomiasis remains a serious public health problem with 200 million people infected and 779 million people at risk worldwide. The schistosomulum and adult worm are two stages of the complex lifecycle of Schistosoma japonicum and excretory/secretory proteins (ESPs) play a major role in host-parasite interactions. In this study, iTRAQ-coupled LC-MS/MS was used to investigate the proteome of ESPs obtained from schistosomula and adult worms of S. japonicum, and 298 differential ESPs were identified. Bioinformatics analysis of differential ESPs in the two developmental stages showed that 161 ESPs upregulated in schistosomula were associated with stress responses, carbohydrate metabolism and protein degradation, whereas ESPs upregulated in adult worms were mainly related to immunoregulation and purine metabolism. Recombinant heat shock protein 70 (HSP70) and thioredoxin peroxidase (TPx), two differential proteins identified in this study, were expressed. Further studies showed that rSjHSP70 and rSjTPx stimulated macrophages expressing high levels of the anti-inflammatory factors TGF-β, IL-10 and Arg-1, and suppressed the expression of the pro-inflammatory cytokines TNF-α, IL-1β, IL-6 and iNOS in LPS-induced macrophages. This study provides new insights into the survival and development of schistosomes in the final host and helps identify vaccine candidates or new diagnostic reagents for schistosomiasis.

  8. Ultrastructural Observation and Gene Expression Profiling of Schistosoma japonicum Derived from Two Natural Reservoir Hosts, Water Buffalo and Yellow Cattle

    PubMed Central

    Yang, Jianmei; Feng, Xingang; Fu, Zhiqiang; Yuan, Chunxiu; Hong, Yang; Shi, Yaojun; Zhang, Min; Liu, Jinming; Li, Hao; Lu, Ke; Lin, Jiaojiao

    2012-01-01

    Water buffalo and yellow cattle are the two of the most important natural reservoir hosts for Schistosoma japonicum in endemic areas of China, although their susceptibility differs, with water buffalo being less conducive to the growth and development of S. japonicum. Results from the current study show that the general morphology and ultrastructure of adult schistosomes derived from the two hosts also differed. Using high-throughput microarray technology, we also compared the gene expression profiles of adult schistosomes derived from the two hosts. We identified genes that were differentially expressed in worms from the two natural hosts. Further analysis revealed that genes associated with protein kinase and phosphatase, the stimulus response, and lipid and nucleotide metabolism were overexpressed, whereas genes associated with reproduction, anatomical structure morphogenesis and multifunctional motif were underexpressed in schistosomes from water buffalo. These differentially expressed genes were mainly involved in nucleotide, energy, lipid metabolism, energy metabolism, transcription, transport and signaling pathway. This suggests that they are key molecules affecting the survival and development of schistosomes in different natural host species. The results of this study add to current understanding of the interplay between parasites and their natural hosts, and provide valuable information for the screening of vaccine candidates or new drug targets against schistosomiasis in the natural reservoir hosts in endemic areas. PMID:23110087

  9. MicroRNAs Are Involved in the Regulation of Ovary Development in the Pathogenic Blood Fluke Schistosoma japonicum

    PubMed Central

    Hu, Chao; Peng, Jinbiao; Luo, Rong; Zhou, Chunjing; Liu, Juntao; Lin, Jiaojiao; Jin, Youxin; Davis, Richard E.; Cheng, Guofeng

    2016-01-01

    Schistosomes, blood flukes, are an important global public health concern. Paired adult female schistosomes produce large numbers of eggs that are primarily responsible for the disease pathology and critical for dissemination. Consequently, understanding schistosome sexual maturation and egg production may open novel perspectives for intervening with these processes to prevent clinical symptoms and to interrupt the life-cycle of these blood-flukes. microRNAs (miRNAs) are key regulators of many biological processes including development, cell proliferation, metabolism, and signal transduction. Here, we report on the identification of Schistosoma japonicum miRNAs using small RNA deep sequencing in the key stages of male-female pairing, gametogenesis, and egg production. We identified 38 miRNAs, including 10 previously unknown miRNAs. Eighteen of the miRNAs were differentially expressed between male and female schistosomes and during different stages of sexual maturation. We identified 30 potential target genes for 16 of the S. japonicum miRNAs using antibody-based pull-down assays and bioinformatic analyses. We further validated some of these target genes using either in vitro luciferase assays or in vivo miRNA suppression experiments. Notably, suppression of the female enriched miRNAs bantam and miR-31 led to morphological alteration of ovaries in female schistosomes. These findings uncover key roles for specific miRNAs in schistosome sexual maturation and egg production. PMID:26871705

  10. Microtopography of the surface of adult Schistosoma japonicum-like (Malaysian) as observed by scanning electron microscopy.

    PubMed

    Sobhon, P; Upatham, E S; Koonchornboon, T; Saitongdee, P; Khunborivan, V; Yuan, H C; Vongpayabal, P; Ow-Yang, C K; Greer, G J

    1983-12-01

    The surface of adult Schistosoma japonicum-like (Malaysian) was studied by scanning electron microscopy. The basic pattern of surface microtopography is similar to other strains of S. japonicum as previously reported. However, among male member there are some unique differences in the types, number and distribution of surface papillae and morphology of ridges. Three kinds of papillae were observed: (1) the large fungiform papillae (3.5-4 micron in diameter, most without cilia) are more numerous than in other strains of S. japonicum, they concentrate on the lateral aspect of the anterior and middle parts close to the edge of the gynecophoral canal, and on the dorso-lateral aspect of the posterior part towards the tail tip; (2) the small hemispherical papillae (1.5-2 micron in diameter, all bearing cilia) are especially numerous in the suckers, the gynecophoral canal and parts of the tegument around the suckers and close to the tail tip; on the rest of the surface they are evenly distributed; (3) the cratered papillae (3-4 micron in diameter, about half having cilia) are more numerous than on other strains, they concentrate on the lateral aspect of the middle part and on the edges of the gynecophoral canal. The surface ridges (about 0.2-0.3 micron in width) are tall, highly branching and perforated; they are most developed in the middle part. Spines were observed only in the suckers and the gynecophoral canals. In contrast to the male, the female has numerous spines on all parts of the surface except the most anterior, where a large number of long cilia were observed. All three kinds of papillae were present; fungiform papillae are more numerous than in females of other strains; they concentrate on the latero-dorsal aspect of middle and posterior parts, and around the excretory pore. Ridges are much less developed than in the male and are prominent only in the middle part.

  11. Tegumental alterations of adult Schistosoma japonicum harbored in mice treated with a single oral dose of mefloquine.

    PubMed

    Xiao, Shu-hua; Xue, Jian; Shen, Bing-gui

    2010-02-01

    To observe the effect of mefloquine on the tegument of adult Schistosoma japonicum harbored in mice. Twelve mice were each infected with 60-80 S. japonicum cercariae. At 35 days post-infection, 10 mice were treated orally with mefloquine at a single dose of 400 mg/kg. Two mice were sacrificed at 8 h, 24 h, 3 days, 7 days, and 14 days post-treatment respectively, and schistosomes were collected by the perfusion technique, fixed and examined under a scanning electron microscope. Schistosomes obtained from the remaining 2 untreated mice served as control. 8 h post-treatment, male and female schistosomes showed focal swelling of the worm body accompanied by extensive swelling, tough junction and fusion of tegumental ridges. Meanwhile, some of the sensory structures showed enlargement and part of them collapsed. 24 h after mefloquine administration, head portion of some male and female worms revealed high swelling accompanied by severe damage to oral sucker. 3 days post-treatment, focal swelling of worm body along the whole worm was universal. In some male and female worms, the damaged tegument fused together to form a large mass protruding from the tegumental surface. In addition, focal or extensive peeling of tegumental ridges was seen or collapse of enlarged sensory structure resulted in formation of hole-like appearance. 7 days post administration, focal swelling of worm body and damage to tegument induced by mefloquine were similar to those aforementioned, but focal peeling, collapse of enlarged sensory structures, and deformation of oral sucker in male and female worms were universal. 14 days post-treatment, individual male worm survived the treatment revealed normal appearance of tegumental ridges in head portion, although light focal swelling of worm body was still observed. Mefloquine causes focal swelling of worm body, extensive and severe damage to the tegument in adult S. japonicum.

  12. Antigen presenting cells may be able to distinguish between normal and radiated Schistosoma japonicum cercaria: an in vitro observation☆

    PubMed Central

    Tang, Guixia; Ji, Minjun; Wu, Haiwei; Wu, Guanling

    2010-01-01

    Objective To observe the discrepancies of responses induced by Schistosoma japonicum (S. japonicum) normal cercaria antigen (NCA) and ultraviolet (UV) -radiation-attenuated cercaria antigen (UVACA) in an in vitro system. Methods S. japonicum cercariae were collected and UVACA and NCA were prepared. Mouse macrophage model cells (RAW 264.7) were treated with medium, NCA (40 µg/mL) or UVACA (40 µg/mL) in the presence or absence of recombinant mouse interferon gamma (rmIFN-γ; 4 ng/mL) for 48 h. Cell surface staining and flow cytometry were used to assess the major histocompatibility complex (MHC)γ; 4 ng/mL) for 48 h. Cell surface staining and flow cytometry were used to assess the major histocompatibility complex (MHC) II expression, and data were expressed as mean fluorescence intensities (MFI). Interleukin (IL) -10, IL-6 and prostaglandin E2 (PGE2) in cell culture supernatant were evaluated by commercial enzyme-linked immunosorbent assays. Results NCA significantly suppressed IFN-γ-induced MHC II expression on RAW 264.7 cells. In the presence of IFN-γ, NCA significantly promoted IL-6, IL-10 and PGE2 secretion from RAW 264.7 cells. In the presence of IFN-γ, UVACA significantly promoted IL-10 but not IL-6 and PGE2 secretion from RAW 264.7 cells and showed no effect on IFN-γ-induced MHC II expression. Compared with UVACA, NCA significantly suppressed IFN-γ-induced MHC II expression and significantly promoted IL-6, PGE2 and IL-10 secretion from RAW 264.7 cells. Conclusion RAW 264.7 cells respond differently to NCA and UVACA. NCA can significantly suppress IFN-γ-induced MHC II expression and significantly promote IL-6, IL-10 and PGE2 secretion from RAW 264.7 cells compared with UVACA. PMID:23554642

  13. [Protective efficacy induced by dendritic cells pulsed with GST in combination with CpG oligodeoxynucleotide against Schistosoma japonicum infection].

    PubMed

    Li, Xiao-Hong; Cao, Jian-Ping; Tang, Lin-Hua; Xu, Yu-Xin; Liu, Shu-Xian; Wang, Sheng-Jun; Cheng, Jing

    2010-06-30

    To study the protective effects on the infection of Schistosoma japonicum in C57BL/6 mice induced by dendritic cells DCs pulsed with GST in combination with CpG oligodeoxynucleotide. GST was purified and used to stimulate DC2.4 cell line. Antigen loading was analyzed by immunofluorescence method. Thirty-five C57BL/6 mice were divided into seven groups(5 mice per group). Mice in groups A, B, C, D and E were immunized subcutaneously with DCs, DCs treated with PSA, DCs pulsed with GST, DCs stimulated with GST+CpG ODN, DCs stimulated with CpG ODN, respectively. For the above five groups, each mouse received 100 microl cell suspension at the density of 10(7)/ml subcutaneously for three times at 2-week intervals. Each mouse of group F was immunized subcutaneously with 50 microg GST formulated in complete Freund's adjuvant first, and 50 microg, 10 microg GST respectively in incomplete Freund's adjuvant for the last two doses. Group G received PBS and served as control. Serum samples were collected 10 days after the final immunization, and were analyzed for specific antibodies by ELISA. At two weeks after the final immunization, each mouse were challenged by 30 +/- 1 cercariae of S. japonicum. Six weeks after infection the mice were sacrificed, and number of worms was counted. Light green fluorescence was observed in dendritic cells under the fluoroscope after pulsing with GST which indicated the protein loaded dendritic cells. The IgG level in groups C, D and F was 0.555 2 +/- 0.078 9, 0.715 0 +/- 0.052 3, and 2.127 0 +/- 0.411 5, respectively, all higher than that of group G (P < 0.05). The worm reduction rate of group D was 53.3%, followed by group F (24.0%) and group C (21.3%). There was no significantly difference in the worm reduction rate between group D and groups F and C (P > 0.05). Dendritic cells pulsed with GST in combination with CpG oligodeoxynucleotide induce significant immunoprotection against the infection of Schistosoma japonicum.

  14. Evaluation of a technique of circumoval precipitin test using blood taken on filter paper and a microtiter technique of complement fixation test of Schistosoma japonicum.

    PubMed

    Tanaka, H; Matsuda, H; Blas, B L; Noseñas, J S

    1975-04-01

    For the circumoval precipitin test (COPT) blood was taken on quantitative blood sampling filter paper by finger prick from outpatients at the Schistosomiasis Control Pilot Project, Palo, Leyte, Philippines. The volume of serum available per strip of filter paper was 0.04 ml and this was extracted at 1:3, 1:5 and 1:8 dilutions. Lyophilized eggs of Schistosoma japonicum were mixed with the diluted serum on a microscope glass slide and incubated at 37 degrees C for 2 days. The reaction was read following the criterion made by Yokogawa et al. [11]. The serum at 1:8 was too dilute to make correct diagnosis; serum at 1:3 dilution contained too much hemoglobin which made microscopic observation difficult and the extract at 1:5 was found to be appropriate. There was no remarkable difference in antigenicity among 3 preparations of lyophilized eggs from Kofu strain, Japan, and those of new and old preparations from Philippine strain. Under the best condition, false negative results appeared in 15.3% of 152 outpatients in Leyte and false positives in 2% of 50 human sera collected in Tokyo. This method of COPT is not satisfactory for the diagnosis of individual cases but is useful in the epidemiological assessment of Schistosoma infections because of the simplicity of blood sampling from dwellers of infested areas and also because it shows nearly the same sensitivity as that of a single fecal examination by the MIFC method. A microtiter technique of complement fixation test (CFT) was also studied. This method, however, was less sensitive than the COPT or a single fecal examination as to give 23.7% false negatives. Frequency distributions of CF and COP titers were analysed among egg positive, egg negative and treated groups. The results showed that treatment with stibophen had little influence in lowering the serum response, especially in COPT.

  15. Multiple vaccinations with UV- attenuated cercariae in pig enhance protective immunity against Schistosoma japonicum infection as compared to single vaccination.

    PubMed

    Lin, Dandan; Tian, Fang; Wu, Haiwei; Gao, Yanan; Wu, Jingjiao; Zhang, Donghui; Ji, Minjun; McManus, Donald P; Driguez, Patrick; Wu, Guanling

    2011-06-10

    Schistosomiasis japonica is a major public health problem in the endemic areas of China, the Philippines, and Indonesia. To date, a vaccine has not been developed against this disease but immunization with UV-attenuated cercariae can induce a high level of protective immunity in Landrace/Yorkshire/Duroc crossbred pigs. To compare the efficacy of a single vaccination and multiple vaccinations with UV-attenuated Schistosoma japonicum cercariae, two groups of pigs received either one or three exposures to 10,000 cercariae attenuated with 400 μw UV. Pigs with a single immunization had a 59.33% reduction in adult worm burden, a 89.87% reduction in hepatic eggs and a 86.27% reduction in fecal eggs at eight weeks post-challenge (P < 0.01). After three immunizations, protection increased to 77.62%, 88.8% and 99.78% reduction in adult worms, hepatic eggs and fecal eggs, respectively (P < 0.01). Humoral and cellular immunological parameters measured indicated that schistosome-specific IgG1 and IgG2 levels in the vaccinated groups were higher than in the infection-control group. Triple vaccinations resulted in higher levels of antibodies, especially IgG2, compared with a single vaccination and IFN-γ levels increased with repeated immunization with UV-irradiated cercariae. The high levels of protection against S. japonicum infection can be achieved with a UV-attenuated vaccine in pigs, and that three vaccinations were possibly more effective than a single vaccination. Moreover, triple vaccinations evoked a more vigorous IFN-γ response and a stronger antibody-mediated response, especially an increase in the levels of IgG2 antibodies.

  16. Genetic variability among Schistosoma japonicum isolates from the Philippines, Japan and China revealed by sequence analysis of three mitochondrial genes.

    PubMed

    Chen, Fen; Li, Juan; Sugiyama, Hiromu; Zhou, Dong-Hui; Song, Hui-Qun; Zhao, Guang-Hui; Zhu, Xing-Quan

    2015-02-01

    The present study examined sequence variability in the mitochondrial (mt) protein-coding genes cytochrome b (cytb), NADH dehydrogenase subunits 2 and 6 (nad2 and nad6) among 24 isolates of Schistosoma japonicum from different endemic regions in the Philippines, Japan and China. The complete cytb, nad2 and nad6 genes were amplified and sequenced separately from individual schistosome. Sequence variations for isolates from the Philippines were 0-0.5% for cytb, 0-0.6% for nad2, and 0-0.9% for nad6. Variation was 0-0.5%, 0.1-0.8%, 0-0.7% for corresponding genes for schistosome samples from mainland China. For worms in Japan, genetic variations were 0-0.2%, 0.1-0.2% and 0 for the three genes, respectively. Sequence variations were 0-1.0%, 0-1.8% and 0-1.1% for cytb, nad2 and nad6, respectively, among schistosome isolates from different geographical strains in the Philippines, Japan and China. Of the three countries, lowest sequence variations were found between isolates from mainland China and the Philippines and highest were detected between Japan and the Philippines in three mtDNA genes. Phylogenetic analyses based on the combined sequences of cytb, nad2 and nad6 revealed that all isolates in the Philippines clustered together sistered to samples from Yunnan and Zhejiang provinces in China, while isolates from Yamanashi in Japan were in a solitary clade. These results demonstrated the usefulness of the combined three mtDNA sequences for studying genetic diversity and population structure among S. japonicum isolates from the Philippines, China and Japan.

  17. Impact of the South-to-North Water Diversion Project on the transmission of Schistosoma japonicum in China.

    PubMed

    Wang, W; Dai, J R; Liang, Y S; Huang, Y X; Coles, G C

    2009-01-01

    The South-to-North Water Diversion Project (SNWDP) is currently the key, national, water-conservation project in China, designed to optimise the use of water resources and relieve the water shortages in the north of the country. As one of the main water intakes for the project, that of the Eastern Route Scheme (ERS), is a breeding site for Oncomelania hupensis (the intermediate host of Schistosoma japonicum), there is concern that the snail may be carried far to the north, in the water passing through the project. To see if they could survive and breed to the north of their current range in China, O. hupensis were collected in marshland near Nanjing City and transferred to cages, on the banks of fish ponds, in the cities of Zhenjiang (in Jiangsu province, at 32 degrees 10'N), Xuzhou (in the same province but at a latitude of 34 degrees 23'N) and Jining (in Shandong province, at 35 degrees 23'N). Except over the first 6 months in Xuzhou, the snails moved north of their natural distribution did not survive and reproduce as well as those in Zhenjiang, and all those transferred to Jining died out within 1 year. Although the snail populations in Xuzhou survived for 7-8 years and retained their infectivity to S. japonicum, histological and histochemical studies revealed abnormalities in the reproductive organs of these snails. It is concluded that, unless global warming significantly increases the minimum winter temperatures in northern China, the SNWDP is unlikely to result in the northward spread of schistosomiasis japonica.

  18. A novel cDNA clone of Schistosoma japonicum encoding the 34,000 Dalton eggshell precursor protein.

    PubMed

    Sugiyama, H; Kawanaka, M; Kameoka, Y; Nakamura, M

    1997-07-01

    A cDNA clone encoding the 34 kDa eggshell protein of Schistosoma japonicum was isolated from an adult female cDNA library with a rabbit antiserum raised against the 34 kDa female worm fraction. A 230 bp-insert of this clone (Sj23A) was introduced in frame into the expression plasmid vector, pMAL-c2, and the recombinant fusion protein of the Sj23A transiation product was induced in Escherichia coli. The antiserum raised against the recombinant protein reacted only with the native 34 kDa protein of mature female worms, which localized in the vitelline cells of the vitelline glands. By reverse transcription-polymerase chain reaction (RT-PCR) analysis, it was found that the gene corresponding to the Sj23A was expressed exclusively in mature female worms. The clone Sj23A showed a high degree of homology to the genes for the eggshell precursor proteins of Fasciola hepatica. At the deduced polypeptide level, the Sj23A also had similarities with the F. hepatica-protein sequence, the amino acid composition [high glycine (16%), lysine (12%) and tyrosine (11%)] and the presence of tyrosine residues flanked by glycine. The clone Sj23A also shared an extensive sequence homology with 3 S. mansoni expression sequence tags (ESTs). The present results suggest that the protein encoded by the female-specific Sj23A gene of S. japonicum is widely conserved in trematodes and plays a significant role as a precursor involved in eggshell formation.

  19. Concomitant cellular and humoral expression of a regulatory cross-reactive idiotype in acute Schistosoma japonicum infection.

    PubMed Central

    Kresina, T F; Olds, G R

    1986-01-01

    In this study the expression of a regulatory cross-reactive idiotype (SJ-CRIM), which is associated with anti-soluble egg antigen (SEA) molecules in murine Schistosoma japonicum infection, is described. Both humoral and cellular components of the immune response were analyzed during the course of infection with S. japonicum. In the humoral immune response, the content of SJ-CRIM decreases as the titer of anti-SEA antibody increases throughout infection. Quantitatively, values for serum ranged from 13.8 +/- 0.3 micrograms of SJ-CRIM, which binds anti-idiotypic antibody per ml of serum at 6 weeks postinfection, to 1.3 +/- 1.8 micrograms/ml at 30 weeks postinfection. Analysis of splenic cell subpopulations for expression of SJ-CRIM revealed that only splenic B cells expressed SJ-CRIM during acute infection (5 to 10 weeks postinfection). On the other hand, thymic cells with a high expression of the SJ-CRIM and Ly-1 marker were observed in acute infections up to 15 weeks postinfection. These data indicate that SJ-CRIM-bearing T cells are selectively localized in acute infection. In addition, the disappearance of expression of SJ-CRIM in serum and cells of chronically infected animals parallels the modulation of granulomatous inflammation and portal hypertension. Results of this study suggest that expression of SJ-CRIM on anti-SEA molecules could represent a marker for acute infection, while its disappearance from serum serves as a marker for modulation of disease. PMID:2873105

  20. Evaluation of protective efficacy induced by different heterologous prime-boost strategies encoding triosephosphate isomerase against Schistosoma japonicum in mice.

    PubMed

    Dai, Yang; Zhao, Song; Tang, Jianxia; Xing, Yuntian; Qu, Guoli; Dai, Jianrong; Jin, Xiaolin; Wang, Xiaoting

    2017-02-28

    In China, schistosomiasis japonica is a predominant zoonotic disease, and animal reservoir hosts in the environment largely sustain infections. The development of transmission-blocking veterinary vaccines is urgently needed for the prevention and efficient control of schistosomiasis. Heterologous prime-boost strategy is more effective than traditional vaccination and homologous prime-boost strategies against multiple pathogens infection. In the present study, to further improve protective efficacy, we immunized mice with three types of heterologous prime-boost combinations based on our previously constructed vaccines that encode triosphate isomerase of Schistosoma japonicum, tested the specific immune responses, and evaluated the protective efficacy through challenge infection in mice. DNA vaccine (pcDNA3.1-SjTPI.opt), adenoviral vectored vaccine (rAdV-SjTPI.opt), and recombinant protein vaccine (rSjTPI) were prepared and three types of heterologous prime-boost combinations, including DNA i.m. priming-rAdV i.m. boosting, rAdV i.m. priming-rAdV s.c. boosting, and rAdV i.m. priming-rSjTPI boosting strategies, were carried out. The specific immune responses and protective efficacies were evaluated in BALB/c mice RESULTS: Results show that different immune profiles and various levels of protective efficacy were elicited by using different heterologous prime-boost combinations. A synergistic effect was observed using the DNA i.m. priming-rAdV i.m. boosting strategy; however, its protective efficacy was similar to that of rAdV i.m. immunization. Conversely, an antagonistic effect was generated by using the rAd i.m. priming-s.c. boosting strategy. However, the strategy, with rAdV i.m. priming- rSjTPI s.c. boosting, generated the most optimal protective efficacy and worm or egg reduction rate reaching up to 70% in a mouse model. A suitable immunization strategy, rAdV i.m. priming-rSjTPI boosting strategy, was developed, which elicits a high level of protective efficacy

  1. [Studies on dynamic changes of proportions of Tc1 and Tc2 cells during Schistosoma japonicum infection].

    PubMed

    Xu, Zhi-Peng; Zhang, Wei-Wei; Li, Yong; Dong, Xiao-Xiao; Li, Sha-Sha; Yang, Xiao-Wei; Chen, Xiao-Jun; Zhu, Ji-Feng; Xue, Xue; Kong, Wen-Jun; Zhou, Sha; He, Lei; Liu, Feng; Su, Chuan

    2012-02-01

    To observe the dynamic changes of the proportions of T cytotoxic type 1 (Tc1) cells and T cytotoxic type 2 (Tc2) cells and analyze the correlation of them with the dynamic changes of the proportions of Th1 and Th2 cells in T lymphocytes respectively at different stages after Schistosoma japonicum infection. Splenocytes were prepared from spleens of mice with S. japonicum infection at different stages (0, 3, 5, 8, 13 weeks), and the proportions of Tc1, Tc2 and Th1, Th2 cells in T cells were determined by FACS, respectively. Compared to the control group (0 week), the proportions of Tc1 cells significantly increased 3, 5, 8, 13 weeks post-infection (all P values < 0.01) and the proportions of Tc2 cells at different stages (5, 8, 13 weeks) post-infection also increased significantly (all P values < 0.01). During the first 3 weeks post-infection, the proportions of Tc1 cells increased most quickly than Tc2 cells did and Tc1 cells did at the other stages post-infection. However, the proportion of Tc2 cells increased most quickly 5 weeks post-infection than both Tc1 cells did and Tc2 cells did at the other stages post-infection. A positive correlation was found between the increases of the proportions of Thl cells and Tc1 cells ( r = 0.978, P = 0.004), and a positive correlation was also found between the increases of the proportions of Th2 cells and Tc2 cells ( r = 0.974, P = 0.005). The SWA stimulation of splenocytes of mice in vitro significantly increased the proportion of Tc1 cells (P < 0.01) while the SEA stimulation of splenocytes of mice in vitro significantly increased the proportion of Tc2 cells ( P < 0.01). The proportions of Tc1 cells and Tc2 cells in T cells are significantly increased at different stages after S. japonicum infection. Tc1 cells are increased most quickly 3 weeks post-infection, and Tc2 cells are increased most quickly 5 weeks post-infection. A positive correlation is found between the proportions of Th cells and Tc cells in CD3+ T cells. SWA

  2. Molecular characterization and ligand binding specificity of the PDZ domain-containing protein GIPC3 from Schistosoma japonicum

    PubMed Central

    2012-01-01

    Background Schistosomiasis is a serious global health problem that afflicts more than 230 million people in 77 countries. Long-term mass treatments with the only available drug, praziquantel, have caused growing concerns about drug resistance. PSD-95/Dlg/ZO-1 (PDZ) domain-containing proteins are recognized as potential targets for the next generation of drug development. However, the PDZ domain-containing protein family in parasites has largely been unexplored. Methods We present the molecular characteristics of a PDZ domain-containing protein, GIPC3, from Schistosoma japonicum (SjGIPC3) according to bioinformatics analysis and experimental approaches. The ligand binding specificity of the PDZ domain of SjGIPC3 was confirmed by screening an arbitrary peptide library in yeast two-hybrid (Y2H) assays. The native ligand candidates were predicted by Tailfit software based on the C-terminal binding specificity, and further validated by Y2H assays. Results SjGIPC3 is a single PDZ domain-containing protein comprised of 328 amino acid residues. Structural prediction revealed that a conserved PDZ domain was presented in the middle region of the protein. Phylogenetic analysis revealed that SjGIPC3 and other trematode orthologues clustered into a well-defined cluster but were distinguishable from those of other phyla. Transcriptional analysis by quantitative RT-PCR revealed that the SjGIPC3 gene was relatively highly expressed in the stages within the host, especially in male adult worms. By using Y2H assays to screen an arbitrary peptide library, we confirmed the C-terminal binding specificity of the SjGIPC3-PDZ domain, which could be deduced as a consensus sequence, -[SDEC]-[STIL]-[HSNQDE]-[VIL]*. Furthermore, six proteins were predicted to be native ligand candidates of SjGIPC3 based on the C-terminal binding properties and other biological information; four of these were confirmed to be potential ligands using the Y2H system. Conclusions In this study, we first

  3. Recombinase polymerase amplification combined with a lateral flow dipstick for rapid and visual detection of Schistosoma japonicum.

    PubMed

    Sun, Kui; Xing, Weiwei; Yu, Xinling; Fu, Wenliang; Wang, Yuanyuan; Zou, Minji; Luo, Zhihong; Xu, Donggang

    2016-08-31

    With the continuous decline in prevalence and intensity of Schistosoma japonicum infection in China, more accurate and sensitive methods suitable for field detection become much needed for schistosomiasis control. Here, a novel rapid and visual detection method based on the combination of recombinase polymerase amplification (RPA) and lateral flow dipstick (LFD) was developed to detect S. japonicum DNA in fecal samples. The LFD-RPA assay targeting SjR2 could detect 5 fg S. japonicum DNA, which was identical to qPCR and real-time RPA assay, and showed no cross-reaction with other parasites. The detection could be finished within 15-20 min at a wide temperature range (25-45 °C), and the results could be visualized by naked eye. The diagnostic validity of LFD-RPA assay was further assessed with 14 fecal samples of infected patients diagnosed by Kato-Katz method and 31 fecal samples of healthy persons, and compared with that of Enzyme-linked immunosorbent assay (ELSIA) and Indirect Hemagglutination Assay (IHA). The LFD-RPA assay showed 92.68 % sensitivity, 100 % specificity and excellent diagnostic agreement with the gold standard Kato-Katz test (k = 0.947, Z = 6.36, P < 0.001), whereas ELISA showed 85.71 % sensitivity, 93.55 % specificity, and substantial diagnostic agreement (k = 0.793, Z = 5.31, P < 0.001), and IHA showed 78.57 % sensitivity, 83.87 % specificity, and moderate diagnostic agreement (k = 0.600, Z = 4.05, P < 0.001), indicating that the LFD-RPA was much better than the traditional methods. The LFD-RPA assay established by us is a sensitive, specific, rapid and convenient method for the diagnosis of schistosomiasis, and shows a great potency in field application.

  4. Comparative Analysis of Transcriptional Profiles of Adult Schistosoma japonicum from Different Laboratory Animals and the Natural Host, Water Buffalo

    PubMed Central

    Wu, Chuang; Hou, Nan; Chen, Qijun

    2015-01-01

    Background Schistosomiasis is one of the most widely distributed parasitic diseases in the world. Schistosoma japonicum, a zoonotic parasite with a wide range of mammalian hosts, is one of the major pathogens of this disease. Although numerous studies on schistosomiasis japonica have been performed using laboratory animal models, systematic comparative analysis of whole-genome expression profiles in parasites from different laboratory animals and nature mammalian hosts is lacking to date. Methodology/Principal Findings Adult schistosomes were obtained from laboratory animals BALB/c mice, C57BL/6 mice, New Zealand white rabbits and the natural host, water buffaloes. The gene expression profiles of schistosomes from these animals were obtained and compared by genome-wide oligonucleotide microarray analysis. The results revealed that the gene expression profiles of schistosomes from different laboratory animals and buffaloes were highly consistent (r>0.98) genome-wide. Meanwhile, a total of 450 genes were identified to be differentially expressed in schistosomes which can be clustered into six groups. Pathway analysis revealed that these genes were mainly involved in multiple signal transduction pathways, amino acid, energy, nucleotide and lipid metabolism. We also identified a group of 1,540 abundantly and stably expressed gene products in adult worms, including a panel of 179 Schistosoma- or Platyhelminthes-specific genes that may be essential for parasitism and may be regarded as novel potential anti-parasite intervention targets for future research. Conclusions/Significance This study provides a comprehensive database of gene expression profiles of schistosomes derived from different laboratory animals and water buffaloes. An expanded number of genes potentially affecting the development of schistosomes in different animals were identified. These findings lay the foundation for schistosomiasis research in different laboratory animals and natural hosts at the

  5. Comparative Analysis of Transcriptional Profiles of Adult Schistosoma japonicum from Different Laboratory Animals and the Natural Host, Water Buffalo.

    PubMed

    Liu, Shuai; Zhou, Xiaosu; Piao, Xianyu; Wu, Chuang; Hou, Nan; Chen, Qijun

    2015-08-01

    Schistosomiasis is one of the most widely distributed parasitic diseases in the world. Schistosoma japonicum, a zoonotic parasite with a wide range of mammalian hosts, is one of the major pathogens of this disease. Although numerous studies on schistosomiasis japonica have been performed using laboratory animal models, systematic comparative analysis of whole-genome expression profiles in parasites from different laboratory animals and nature mammalian hosts is lacking to date. Adult schistosomes were obtained from laboratory animals BALB/c mice, C57BL/6 mice, New Zealand white rabbits and the natural host, water buffaloes. The gene expression profiles of schistosomes from these animals were obtained and compared by genome-wide oligonucleotide microarray analysis. The results revealed that the gene expression profiles of schistosomes from different laboratory animals and buffaloes were highly consistent (r>0.98) genome-wide. Meanwhile, a total of 450 genes were identified to be differentially expressed in schistosomes which can be clustered into six groups. Pathway analysis revealed that these genes were mainly involved in multiple signal transduction pathways, amino acid, energy, nucleotide and lipid metabolism. We also identified a group of 1,540 abundantly and stably expressed gene products in adult worms, including a panel of 179 Schistosoma- or Platyhelminthes-specific genes that may be essential for parasitism and may be regarded as novel potential anti-parasite intervention targets for future research. This study provides a comprehensive database of gene expression profiles of schistosomes derived from different laboratory animals and water buffaloes. An expanded number of genes potentially affecting the development of schistosomes in different animals were identified. These findings lay the foundation for schistosomiasis research in different laboratory animals and natural hosts at the transcriptional level and provide a valuable resource for screening anti

  6. Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV

    NASA Technical Reports Server (NTRS)

    Lim, Kap; Ho, Joseph X.; Keeling, Kim; Gilliland, Gary L.; Ji, Xinhua; Rueker, Florian; Carter, Daniel C.

    1994-01-01

    The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(sub 3)2(sub 1)2 with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed.

  7. Comparison of genetic diversity and population structure between two Schistosoma japonicum isolates--the field and the laboratory.

    PubMed

    Bian, Chao-Rong; Gao, Yu-Meng; Lamberton, Poppy H L; Lu, Da-Bing

    2015-06-01

    Schistosomiasis japonicum is one of the most important human parasitic diseases, and a number of studies have recently elucidated the difference in biological characteristics of S. japonicum among different parasite isolates, for example, between the field and the laboratory isolates. Therefore, the understanding of underlying genetic mechanism is of both theoretical and practical importance. In this study, we used six microsatellite markers to assess genetic diversity, population structure, and the bottleneck effect (a sharp reduction in population size) of two parasite populations, one field and one laboratory. A total of 136 S. japonicum cercariae from the field and 86 from the laboratory, which were genetically unique within single snails, were analyzed. The results showed bigger numbers of alleles and higher allelic richness in the field parasite population than in the laboratory indicating lower genetic diversity in the laboratory parasites. A bottleneck effect was detected in the laboratory population. When the field and laboratory isolates were combined, there was a clear distinction between two parasite populations using the software Structure. These genetic differences may partially explain the previously observed contrasted biological traits.

  8. Contribution of silver ions to the inhibition of infectivity of Schistosoma japonicum cercariae caused by silver nanoparticles.

    PubMed

    Cheng, Yuli; Chen, Xiao; Song, Wenjian; Kong, Zheng; Li, Peijing; Liu, Yanqun

    2013-04-01

    Blockage of pathogen transmission through water decontamination is considered an important strategy for the prevention of schistosome infection. Many believe that this strategy is feasible, but it has yet to be achieved. Silver has a long history of use as a disinfectant. With the emergence of nanotechnology, silver can be shaped into nanoparticles which have been found to possess superb antimicrobial activities. In this light, we investigated the effects of silver nanoparticles (AgNPs) on Schistosoma japonicum cercariae. AgNPs rapidly induced cercarial tail-shedding, agitated behaviour and a decrease in cercarial secretion in a dose-dependent manner. Prolonged treatment was found to be cercariocidal, which nevertheless might be attributable to AgNP-induced cercarial tail loss rather than to toxicity. Higher concentrations of AgNPs (125 μg mL-1 and above) completely blocked cercarial infectivity. Despite decreased infectivity, cercariae exposed to lower concentrations of AgNPs for 30 min were still found capable of infecting hosts even without their tails, suggesting that tail loss does not necessarily signify a total loss of infective ability. We also found that silver ions (Ag+) were heavily involved in the observed cercarial responses of AgNPs. Our observations provide insight into the interactions between the larvae of helminth parasites and nanoparticles.

  9. SjE16.7 activates macrophages and promotes Schistosoma japonicum egg-induced granuloma development.

    PubMed

    Fang, Yan; Wu, Chenyun; Chen, Qing; Wu, Jianhua; Yang, Yang; Guo, Xiaokui; Chen, Guangjie; Wang, Zhaojun

    2015-09-01

    SjE16.7 is an egg-specific protein from Schistosoma japonicum that recruits neutrophils and initiates an inflammatory granuloma response in host tissue. However, since macrophages are known to be important regulators of egg granuloma formation we investigated the effect of SjE16.7 on this cell type. Here we report that SjE16.7 is a potent macrophage activator, inducing macrophage chemotaxis and stimulating cytokine production. Treatment of murine primary macrophages with SjE16.7 resulted in upregulation of both pro- and anti-inflammatory cytokines (IL-10, IL-12, IL-6 and TNF-α), as well as phosphorylation of mitogen-activated protein kinases (MAPKs). Moreover, SjE16.7 treatment increased MHC Class II expression on the surface of macrophages. Importantly, in vivo blockade of SjE16.7 significantly reduced egg-induced pathology, as a result of decreased leucocyte infiltration and reduced granuloma size. Our results suggest that SjE16.7 is an important pathogenic factor and a potential treatment target for this disease.

  10. Expression, crystallization and preliminary X-ray diffraction analysis of thioredoxin glutathione reductase from Schistosoma japonicum in complex with FAD

    PubMed Central

    Li, Yongdong; Wu, Qunfeng; Peng, Yun; Huang, Fuyan; Li, Xun; Chen, Lin; Shi, Dashuang; Zhou, Xiaonong; Fan, Xiaolin

    2014-01-01

    Thioredoxin glutathione reductase from Schistosoma japonicum (SjTGR), a multifunctional enzyme, plays a vital role in antioxidant pathways and is considered to be a potential drug target for the development of antischistosomal chemotherapy. In this study, two constructs of a truncated form of SjTGR without the last two residues (Sec597–Gly598) were cloned, overexpressed and purified using wild-type and codon-optimized genes. Only SjTGR from the wild-type gene was found to form a complex with flavin adenine dinucleotide (FAD), which could be crystallized in the orthorhombic space group P212121, with unit-cell parameters a = 84.185, b = 86.47, c = 183.164 Å, at 295 K using the hanging-drop vapour-diffusion method. One dimer was present in the crystallographic asymmetric unit and the calculated Matthews coefficient (V M) and solvent content were 2.6 Å3 Da−1 and 52.8%, respectively. Structural determination of SjTGR is in progress using the molecular-replacement method. PMID:24419626

  11. Studies on the protective immunity of Schistosoma japonicum bivalent DNA vaccine encoding Sj23 and Sj14.

    PubMed

    Yuan, Hu; You-En, Shi; Long-Jiang, Yu; Xiao-Hua, Zhu; Liu-Zhe, Li; Cash, Melanie; Lu, Zhu; Zhi, Liu; Deng-Xin, Song

    2007-04-01

    In order to explore the high performance bivalent DNA vaccine of Schistosoma japonicum, the fatty-acid-binding protein (Sj14) and the 23 kDa transmembrane protein (Sj23) two proteins were selected to construct the DNA-based vaccine. It was successful to construct a bivalent DNA vaccine using three strategies: the co-expression of two genes, a fusion gene expression and two kinds of plasmids in combination (cocktail vaccine). The bivalent DNA was proven to express well in vitro and in vivo by indirect immunofluorescence test (IIF) and reverse transcriptase-polymerase chain reaction (RT-PCR). The protective immunity of bivalent DNA vaccine was higher than that of univalent DNA vaccine (p<0.05). There were four groups of bivalent vaccine whose protective immunity was higher than 50%. Granuloma diameter reduction rates were in the range of 18-39%. There was no significant impact on immunity protection exerted by the four factors including dosage, inoculated times, inoculated routes and challenge time after the last immunization in three levels (p>0.05).

  12. 3-Oxoacyl-ACP Reductase from Schistosoma japonicum: Integrated In Silico-In Vitro Strategy for Discovering Antischistosomal Lead Compounds

    PubMed Central

    Liu, Jian; Dyer, Dave; Wang, Jipeng; Wang, Shuqi; Du, Xiaofeng; Xu, Bin; Zhang, Haobing; Wang, Xiaoning; Hu, Wei

    2013-01-01

    Background Schistosomiasis is a disease caused by parasitic worms and more than 200 million people are infected worldwide. The emergence of resistance to the most commonly used drug, praziquantel (PZQ), makes the development of novel drugs an urgent task. 3-oxoacyl-ACP reductase (OAR), a key enzyme involved in the fatty acid synthesis pathway, has been identified as a potential drug target against many pathogenic organisms. However, no research on Schistosoma japonicum OAR (SjOAR) has been reported. The characterization of the SjOAR protein will provide new strategies for screening antischistosomal drugs that target SjOAR. Methodology/Principal Findings After cloning the SjOAR gene, recombinant SjOAR protein was purified and assayed for enzymatic activity. The tertiary structure of SjOAR was obtained by homology modeling and 27 inhibitor candidates were identified from 14,400 compounds through molecular docking based on the structure. All of these compounds were confirmed to be able to bind to the SjOAR protein by BIAcore analysis. Two compounds exhibited strong antischistosomal activity and inhibitory effects on the enzymatic activity of SjOAR. In contrast, these two compounds showed relatively low toxicity towards host cells. Conclusions/Significance The work presented here shows the feasibility of isolation of new antischistosomal compounds using a combination of virtual screening and experimental validation. Based on this strategy, we successfully identified 2 compounds that target SjOAR with strong antischistosomal activity but relatively low cytotoxicity to host cells. PMID:23762275

  13. Regulation of egg antigen-induced in vitro proliferative response by splenic suppressor T cells in murine Schistosoma japonicum infection.

    PubMed Central

    Stavitsky, A B; Olds, G R; Peterson, L B

    1985-01-01

    Beginning about 5 weeks after infection, C57BL/6J mice infected with Schistosoma japonicum developed granulomas around parasite eggs trapped in the liver. These granulomas attained peak size about 9 weeks after infection and then spontaneously regressed. This regression was also induced by the injection of serum immunoglobulin G1 but not lymphoid cells from chronically infected mice, but it was conceivable that lymphoid cells from mice infected for 10 weeks could also induce regression. We investigated the possibility of cellular suppression of egg antigen-induced immune responses by coculturing spleen cells from 5- to 6-week-infected mice with spleen cells from mice infected for 10 weeks or longer. Mitomycin C-resistant Thy 1.2+, Lyt 2.2+ splenic T cells from mice infected for 10 to 25 weeks consistently suppressed the egg antigen-stimulated proliferation of spleen cells from 5- to 6-week-infected mice. Suppression was dependent upon specific antigen and optimal concentrations of egg antigen and T suppressor cells. Once induced, the suppressor cells were nonspecific. Cultured T cells from uninfected mice also occasionally suppressed the acute spleen cell proliferative response, but these cells were mitomycin C sensitive. These in vitro observations suggest that granulomatous inflammation in vivo may also be down regulated by suppressor T cells and that these cells may also be implicated in the nonspecific depression of cellular and humoral responses to antigens observed during the course of this infection. PMID:3161831

  14. The Differential Expression of Immune Genes between Water Buffalo and Yellow Cattle Determines Species-Specific Susceptibility to Schistosoma japonicum Infection.

    PubMed

    Yang, Jianmei; Fu, Zhiqiang; Hong, Yang; Wu, Haiwei; Jin, Yamei; Zhu, Chuangang; Li, Hao; Lu, Ke; Shi, Yaojun; Yuan, Chunxiu; Cheng, Guofeng; Feng, Xingang; Liu, Jinming; Lin, Jiaojiao

    2015-01-01

    Water buffalo are less susceptible to Schistosoma japonicum infection than yellow cattle. The factors that affect such differences in susceptibility remain unknown. A Bos taurus genome-wide gene chip was used to analyze gene expression profiles in the peripheral blood of water buffalo and yellow cattle pre- and post-infection with S. japonicum. This study showed that most of the identified differentially expressed genes (DEGs) between water buffalo and yellow cattle pre- and post-infection were involved in immune-related processes, and the expression level of immune genes was lower in water buffalo. The unique DEGs (390) in yellow cattle were mainly associated with inflammation pathways, while the unique DEGs (2,114) in water buffalo were mainly associated with immune-related factors. The 83 common DEGs may be the essential response genes during S. japonicum infection, the highest two gene ontology (GO) functions were associated with the regulation of fibrinolysis. The pathway enrichment analysis showed that the DEGs constituted similar immune-related pathways pre- and post-infection between the two hosts. This first analysis of the transcriptional profiles of natural hosts has enabled us to gain new insights into the mechanisms that govern their susceptibility or resistance to S. japonicum infections.

  15. The Differential Expression of Immune Genes between Water Buffalo and Yellow Cattle Determines Species-Specific Susceptibility to Schistosoma japonicum Infection

    PubMed Central

    Yang, Jianmei; Fu, Zhiqiang; Hong, Yang; Wu, Haiwei; Jin, Yamei; Zhu, Chuangang; Li, Hao; Lu, Ke; Shi, Yaojun; Yuan, Chunxiu; Cheng, Guofeng; Feng, Xingang; Liu, Jinming; Lin, Jiaojiao

    2015-01-01

    Water buffalo are less susceptible to Schistosoma japonicum infection than yellow cattle. The factors that affect such differences in susceptibility remain unknown. A Bos taurus genome-wide gene chip was used to analyze gene expression profiles in the peripheral blood of water buffalo and yellow cattle pre- and post-infection with S. japonicum. This study showed that most of the identified differentially expressed genes(DEGs) between water buffalo and yellow cattle pre- and post-infection were involved in immune-related processes, and the expression level of immune genes was lower in water buffalo. The unique DEGs (390) in yellow cattle were mainly associated with inflammation pathways, while the unique DEGs (2,114) in water buffalo were mainly associated with immune-related factors. The 83 common DEGs may be the essential response genes during S. japonicum infection, the highest two gene ontology (GO) functions were associated with the regulation of fibrinolysis. The pathway enrichment analysis showed that the DEGs constituted similar immune-related pathways pre- and post-infection between the two hosts. This first analysis of the transcriptional profiles of natural hosts has enabled us to gain new insights into the mechanisms that govern their susceptibility or resistance to S. japonicum infections. PMID:26125181

  16. Efficacy and Safety of Different Dosages of Praziquantel for the Treatment of Schistosoma Japonicum: A Systematic Review and Meta-Analysis

    PubMed Central

    Cai, Damin; Zhang, Si; Wu, Julong; Wang, Xun; Wang, Meng; Lu, Xiaoling; Chen, Huiyu; Wang, Qian; Ma, Xingming

    2014-01-01

    Background: Praziquantel, an antischistosomal compound, is used as first-line drug for chemotherapy of Schistosoma japonicum since 1984. In this article, we conducted a systematic review and mete-analysis to evaluate the efficacy and safety of different dosages of praziquantel (PZQ) for treatment of Schistosoma japonicum. Evidence Acquisition: A number of six articles published in peer-reviewed journals before December 2012 were selected for analysis after searching the following literature databases: PubMed/Medline, the Chinese WanFang Literature Database, China National Knowledge Infrastructure (1994-2012.12), and the Chinese Biomedical Literature (1978-2012.12). Results: The meta-analyses showed that there is no statistically significant difference of the negative rate on the egg using 40 mg/kg compared to 60 mg/kg PZQ for S. japonicum treatment (RR 0.79, 95% CI 0.46 1.35; P < 0.39). The meta-analysis showed that there is no statistically significant difference of the side effects using 30 mg/kg compared with 40 mg/kg (RR 0.97, 95% CI 0.68 1.38; P = 0.87), 40 mg/kg compared with 60 mg/kg (RR 0.79, 95% CI 0.46 1.35; P = 0.39) and 50 mg/kg compared with 60 mg/kg (RR 0.89, 95% CI 0.56 1.42; P = 0.63). Conclusions: According to the results, there is no statistically significant difference in different doses of PZQ for treating S. japonicum. PMID:25558390

  17. Genetic and household risk factors for Schistosoma japonicum infection in the presence of larger scale environmental differences in the mountainous transmission areas of China.

    PubMed

    Seto, Edmund Y W; Zhong, Bo; Kouch, John; Hubbard, Alan; Spear, Robert C

    2005-12-01

    Schistosoma japonicum egg excretion and kinship relationship data from 13 endemic villages in the mountainous transmission area near Xichang, in Sichuan province, China, were analyzed via a variance components methodology to assess the relative contribution of kinship, shared household, and shared village to the risk of infection. Large intervillage differences in egg counts exist in this region due to differences in transmission potential related to environmental differences in snail density and agricultural practices. After accounting for these intervillage differences, there was no kinship or household effect on egg excretion. This reinforces earlier findings that suggest environmental factors dominate risk in this region.

  18. Immune responses result in misdiagnosis of Schistosoma japonicum by immunodiagnosis kits in egg-positive patients living in a low schistosomiasis transmission area of China

    PubMed Central

    2014-01-01

    Background In recent field surveys, we failed to detect the presence of specific antibody against Schistosoma japonicum in some egg-positive patients by commonly used immunodiagnostic kits. To find out whether low levels of specific antibody truly exist among egg-positive individuals and elucidate the underlying immune mechanisms, we carried out a cross-sectional epidemiologic study in a S. japonicum low transmission endemic area of Poyang Lake region, China and compared the humoral and cellular immune characteristics between S. japonicum high and low antibody responders. Methods Kato–Katz thick smear assay was used to determine the schistosomiasis status of 3,384 participants residing in two Poyang Lake region villages, Jiangxi, China. Among the 142 stool egg-positive participants, we identified low and high S. japonicum antibody responders with soluble egg antigen (SEA) and adult worm antigen (AWA) specific IgG levels by adopting ROC curve analysis. To compare the humoral and cellular immune responses between high and low S. japonicum antibody responders, serum specific antibody levels as well as the percentage of T lymphocyte subpopulation in PMBC, and cell stimulated cytokines (IFN- gamma and interlukin-10) were detected. Results Eight S. japonicum egg-positive participants were defined as low antibody responders. Although the percentage of CD3+T cells in low responders was slightly higher and the percentage of CD4+ T cells, CD8+ T cells, the ratio of CD4+/CD8+ and CD4+ CD25+ Treg cells were lower than those in high responders, the differences between the two groups were not significant (P > 0.05). AWA -stimulated interlukin-10 level was significantly higher in high responders, while other cytokines did not show differences between two groups. For antibody profiles, except AWA specific IgA, significant differences of each antibody isotype between low and high responders were detected (P < 0.05). Conclusions Our study confirmed that there are S

  19. [Characterization and immunoprotective effect of SjIrV1, a 66 kDa calcium-binding protein from Schistosoma japonicum].

    PubMed

    Wei, Meimei; Xiong, Yanian; Hong, Yang; Huang, Lini; Meng, Peipei; Ai, Dezhou; Zhang, Min; Fu, Zhiqiang; Liu, Shengfa; Lin, Jiaojiao

    2013-07-01

    Calcium-binding protein is an indispensable protein which performs extensive and important functions in the growth of Schistosoma japonicum. Based on our primary study on tegument surface proteins of S. japonicun, a cDNA encoding a 66 kDa calcium-binding protein of S. japonicum (Chinese strain) was cloned, sequence analysis revealed that it was identical with that of SjIrV1 of Philippines strains S. japonicum. The expression of SjIrV1 were detected by Real-time PCR, using cDNA templates isolated from 7, 14, 21, 28, 35 and 42 days worms and the results revealed that the gene was expressed in all investigated stages, and the mRNA level of SjIrV1 is much higher in 42 d female worms than that in 42 d male worms. The cDNA containing the open reading frame of IrV1 was subcloned into a pET28a (+) vector and transformed into competent Escherichia coli BL21 for expression. The recombinant protein was purified using a Ni-NTA purification system, and confirmed by high performance liquid chromatography (RP-HPLC) and tandem mass spectrometry (MS/MS). Western blotting analysis showed that recombinant SjIrV1 (rSjIrV1) could be recognized by the S. japonicum infected mouse serum and the mouse serum specific to rSjIrV1, respectively. Immunofluorescence observation exhibited that SjIrV1 was mainly distributed on the tegument of the 35-day adult worms. ELISA test revealed that IgG, IgG1 and IgG2a antibodies are significantly increased in the serum of rSjIrV1 vaccinated mice. The study suggested that rSjIrV1 might play an important role in the development of S. japonicum.

  20. [Cloning, expression and immunodiagnostic analysis of Schistosoma japonicum calcium-binding EF-hand domain containing protein].

    PubMed

    Lu, Yan; Xu, Bin; Ju, Chuan; Mo, Xiao-Jin; Chen, Shen-Bo; Feng, Zheng; Wang, Xiao-Ning; Hu, Wei

    2012-06-30

    To clone and expression Schistosoma japonicum calcium-binding EF-hand domain containing protein (SjEFCAB), purify the expressed protein, and evaluate its antigenicity and diagnostic value. The positive clone screened from egg cDNA library was used as template to amplify the SjEFCAB gene by PCR. The target fragment was cloned into prokaryotic expression vector pGEX-4T-1. The positive recombinant plasmids were transformed into E.coli BL21 and induced by IPTG for expression of the protein. The recombinant protein was purified with GST-tag affinity chromatography. Western blotting was used to analyze the antigenicity. The purified protein was used as coating antigen for indirect ELISA to evaluate its diagnostic effect. Serum samples from patients with schistosomiasis japonica (78 cases), clonorchiasis sinensis (5 cases), cysticercosis (10 cases), paragonimiasis westermani (6 cases), trichinosis (9 cases) and healthy persons (50 cases) were examined. The recombinant plasmid pGEX-4T-1-SjEFCAB was constructed and the SjEFCAB recombinant protein (Mr 8 200) was expressed in E. coli. The soluble fusion protein was purified with affinity chromatography. Western blotting analysis showed that the recombinant protein was recognized by sera of infected rabbits and pooled sera of schistosomiasis japonica patients. The sensitivity and specificity of ELISA for diagnosis of schistosomiasis japonica were 82.1% (64/78) and 95.0% (76/80), respectively. The cross reaction with sera of clonorchiasis sinensis, cysticercosis, and trichinosis patients were 1/5, 1/10, and 1/9, respectively. There was no cross reaction with sera of paragonimiasis westermani patients. The recombinant SjEFCAB antigen has potential diagnostic value for schistosomiasis japonica.

  1. Further studies on mefloquine and praziquantel alone or interaction of both drugs against Schistosoma japonicum in vitro.

    PubMed

    Xiao, Shu-hua; Xue, Jian; Zhang, Hao-bing

    2012-03-01

    The aim of the present study is to further understand and analyze the interaction of mefloquine with praziquantel against adult Schistosoma japonicum in vitro. Mice infected with S. japonicum cercariae for 35-37 days were sacrificed, and adult schistosomes were collected by perfusion. Schistosomes were placed to each of 12 wells of a Falcon plate and maintained in RPMI 1640 supplemented by 10% calf serum. For determination of 50% and 95% lethal concentration (LC50 and LC95) of the two drugs in vitro, schistosomes were exposed to mefloquine at concentrations of 1, 2, 3, 4, 5, 6, 7, and 10 μg/mL or praziquantel at concentrations of 0.001, 0.01, 0.05, 0.1, 0.2, 0.5, 1, 10, and 30 μg/mL. The plate was incubated at 37°C in 95% air + 5% CO₂ for 72 h. According to the half-life of oral mefloquine and praziquantel in mice, mefloquine combined with praziquantel simultaneously, mefloquine administered within 1 h after praziquantel and praziquantel administered within 17 h after mefloquine were used to evaluate the effect of mefloquine in combination with praziquantel against S. japonicum in vitro. The results showed that the LC50 and LC95 of mefloquine calculated by the Bliss method were 6.17 μg/mL (95% confidence limits, 5.84-6.517 μg/mL) and 8.703 μg/mL (95% confidence limits, 7.632-9.797 μg/mL), respectively. As to praziquantel, no worm death was seen when schistosomes were exposed to praziquantel at concentrations of 0.005-0.2 μg/mL for 72 h. While in the worms exposed to praziquantel 1, 10, and 30 μg/mL, strong spasmodic contractions of the worm body and vesiculation along the worm surface were observed, but 48-75% of the schistosomes survived the exposure in 72-h incubation. Meanwhile, the number of dead worms that emerged in each group was not proportion to the increasing concentrations. Therefore, it is not appropriate to calculate the LC50 and LC95 of praziquantel. For evaluation of the interaction with the two drugs, praziquantel 0.1 or 0.2

  2. Confocal laser scanning microscopic observation on adult Schistosoma japonicum harbored in mice following treatment with single-dose mefloquine.

    PubMed

    Xiao, Shu-Hua; Sun, Jun; Xue, Jian

    2012-06-01

    The aim of the present study is to assess the mefloquine-induced alteration of adult Schistosoma japonicum using confocal laser scanning microscopy (CLSM). Eight out of ten mice infected with 60-80 S. japonicum cercariae for 35 days were treated orally with mefloquine at a single dose of 400 mg/kg. Four groups of two mice were killed at 24 h and 3, 7, and 14 days post-treatment, and schistosomes were collected by perfusion from the liver and mesenteric veins, fixed in 70% alcohol, stained with acid carmine, and examined by CLSM. Worms obtained from untreated mice served as controls. Twenty-four hours post-treatment, focal tegument of adult male and female worms, which composed of fine and short villus-like materials, became thicker and longer, or disorder arrangement, while the musculatures beneath the tegument revealed in focal and irregular swelling with various degrees. In the gut of male and female schistosomes, severe dilatation accompanied by swelling, collapse, and peeling of gut mucosa was universal. In the reproductive organs, no apparent alteration in the testis structure of male worms was seen, while in female worms, slight damage to the ovary included loose arrangement of mature ovary cells accompanied by some of them degenerated and collapsed. As to vitelline glands, severe damage, such as swelling, indistinction, fusion or collapse of vitelline cells, and apparent swelling of parenchymal tissues in vitelline gland lobules, was seen. Meanwhile, abnormal ova emerged in the uterus at this time point. Three to 7 days post-treatment, the damage to the worms aggravated either in extent or in severity along with time. In some focally swollen worm body, the parenchymal tissues revealed in severe swelling. In addition, a large piece of degenerated and necrotic parenchymal tissues emerged closed to the severe destructed oral or ventral sucker. In the gut of male and female worms, the major alterations manifested by focal collapse or peeling of mucosa, and

  3. Enhancement of Protective Efficacy through Adenoviral Vectored Vaccine Priming and Protein Boosting Strategy Encoding Triosephosphate Isomerase (SjTPI) against Schistosoma japonicum in Mice

    PubMed Central

    Dai, Yang; Wang, Xiaoting; Tang, Jianxia; Zhao, Song; Xing, Yuntian; Dai, Jianrong; Jin, Xiaolin; Zhu, Yinchang

    2015-01-01

    Background Schistosomiasis japonica is a zoonotic parasitic disease; developing transmission blocking veterinary vaccines are urgently needed for the prevention and control of schistosomiasis in China. Heterologous prime-boost strategy, a novel vaccination approach, is more effective in enhancing vaccine efficacy against multiple pathogens. In the present study, we established a novel heterologous prime-boost vaccination strategy, the rAdV-SjTPI.opt intramuscular priming and rSjTPI subcutaneous boosting strategy, and evaluated its protective efficacy against Schistosoma japonicum in mice. Methodology/Principal Findings Adenoviral vectored vaccine (rAdV-SjTPI.opt) and recombinant protein vaccine (rSjTPI) were prepared and used in different combinations as vaccines in a mouse model. The specific immune responses and protective efficacies were evaluated. Furthermore, the longevity of protective efficacy was also determined. Results showed that the rAdV-SjTPI.opt priming-rSjTPI boosting strategy elicited higher levels of specific IgG responses and broad-spectrum specific cellular immune responses. The protective efficacy could reach up to nearly 70% and 50% of protection could be observed at 10 weeks after the last immunization in mice. Conclusions/Significance The rAdV-SjTPI.opt intramuscular priming-rSjTPI subcutaneous boosting vaccination strategy is a novel, highly efficient, and stable approach to developing vaccines against Schistosoma japonicum infections in China. PMID:25793406

  4. Gene Gun Bombardment with DNA-Coated Golden Particles Enhanced the Protective Effect of a DNA Vaccine Based on Thioredoxin Glutathione Reductase of Schistosoma japonicum

    PubMed Central

    Cao, Yan; Zhao, Bin; Han, Yanhui; Zhang, Juan; Li, Xuezhen; Qiu, Chunhui; Wu, Xiujuan; Hong, Yang; Ai, Dezhou; Lin, Jiaojiao; Fu, Zhiqiang

    2013-01-01

    Schistosomiasis, caused by infection with Schistosoma species, remains an important parasitic zoonosis. Thioredoxin glutathione reductase of Schistosoma japonicum (SjTGR) plays an important role in the development of the parasite and for its survival. Here we present a recombinant plasmid DNA vaccine, pVAX1/SjTGR, to estimate its protection against S. japonicum in BALB/c mice. The DNA vaccine administrated by particle bombardment induced higher protection than by intramuscular injection. All animals vaccinated with pVAX1/SjTGR developed significant specific anti-SjTGR antibodies than control groups. Moreover, animals immunized by gene gun exhibited a splenocyte proliferative response, with an increase in IFN-γ and IL-4. The recombinant plasmid administrated by gene gun achieved a medium protective efficacy of 27.83–38.83% (P < 0.01) of worm reduction and 40.38–44.51% (P < 0.01) of liver egg count reduction. It suggests that different modes of administering a DNA vaccine can influence the protective efficacy induced by the vaccine. Interestingly, from the enzymatic activity results, we found that worms obtained from pVAX1/SjTGR-vaccinated animals expressed lower enzymatic activity than the control group and the antibodies weakened the enzymatic activity of SjTGR in vitro, too. It implies that the high-level antibodies may contribute to the protective effects. PMID:23509820

  5. Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV

    NASA Technical Reports Server (NTRS)

    Lim, K.; Ho, J. X.; Keeling, K.; Gilliland, G. L.; Ji, X.; Ruker, F.; Carter, D. C.

    1994-01-01

    The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) (Muster T et al., 1993, J Virol 67:6642-6647) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class (Ji X, Zhang P, Armstrong RN, Gilliland GL, 1992, Biochemistry 31:10169-10184) was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(3)2(1)2, with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed.

  6. Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV

    NASA Technical Reports Server (NTRS)

    Lim, K.; Ho, J. X.; Keeling, K.; Gilliland, G. L.; Ji, X.; Ruker, F.; Carter, D. C.

    1994-01-01

    The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) (Muster T et al., 1993, J Virol 67:6642-6647) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class (Ji X, Zhang P, Armstrong RN, Gilliland GL, 1992, Biochemistry 31:10169-10184) was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(3)2(1)2, with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed.

  7. Soluble Egg Antigens of Schistosoma japonicum Induce Senescence of Activated Hepatic Stellate Cells by Activation of the FoxO3a/SKP2/P27 Pathway

    PubMed Central

    Chen, Jinling; Zhu, Dandan; Wang, Jianxin; Sun, Xiaolei; Chen, Liuting; Wu, Liting

    2016-01-01

    Background Liver fibrosis was viewed as a reversible process. The activation of hepatic stellate cells (HSCs) is a key event in the process of liver fibrosis. The induction of senescence of HSCs would accelerate the clearance of the activated HSCs. Previously, we demonstrated that soluble egg antigens (SEA) of Schistosoma japonicum promoted the senescence of HSCs via STAT3/P53/P21 pathway. In this paper, our study was aimed to explore whether there are other signaling pathways in the process of SEA-induced HSCs aging and the underlying effect of SKP2/P27 signal on senescent HSCs. Methodology/Principal findings Human hepatic stellate cell line, LX-2 cells, were cultured and stimulated with SEA. Western blot and cellular immunofluorescence analysis were performed to determine the expression of senescence-associated protein, such as P27, SKP2 and FoxO3a. Besides, RNA interfering was applied to knockdown the expression of related protein. The senescence of HSCs was determined by senescence-associated β-gal staining. We found that SEA increased the expression of P27 protein, whereas it inhibited the expression of SKP2 and FoxO3a. Knockdown of P27 as well as overexpression of SKP2 both suppressed the SEA-induced senescence of HSCs. In addition, the nuclear translocation of FoxO3a from the nucleus to the cytoplasm was induced by SEA stimulation. Conclusions/Significance The present study demonstrates that SEA promotes HSCs senescence through the FoxO3a/SKP2/P27 pathway. PMID:28036393

  8. Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV.

    PubMed Central

    Lim, K.; Ho, J. X.; Keeling, K.; Gilliland, G. L.; Ji, X.; Rüker, F.; Carter, D. C.

    1994-01-01

    The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) (Muster T et al., 1993, J Virol 67:6642-6647) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class (Ji X, Zhang P, Armstrong RN, Gilliland GL, 1992, Biochemistry 31:10169-10184) was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(3)2(1)2, with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed. PMID:7538846

  9. Anti-CD25 monoclonal antibody enhances the protective efficacy of Schistosoma japonicum GST vaccine via inhibition of CD4(+)CD25(+)Foxp3(+) regulatory T cells.

    PubMed

    Tang, Chun-Lian; Yang, Jin; Cheng, Liang-Yu; Cheng, Lan-Fang; Liu, Zhi-Ming

    2017-08-21

    The effect of anti-CD25 monoclonal antibody (anti-CD25 mAb) on the protection efficacy of Schistosoma japonicum 26 kDa GST (glutathione-S-transferase) vaccine was evaluated. Mice were immunized with GST before infection with S. japonicum cercariae and then injected with anti-CD25 mAb. The worm reduction rate was promoted from 24.18% in mice with GST immunization to 47.09% in mice with GST plus anti-CD25 mAb. Compared with the control group, the percentages of splenic CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) were significantly lower after administration of anti-CD25 mAb; meanwhile, elevated levels of IFN-γ and IL-2 were secreted by splenocytes. These results indicate that the poor protective efficacy of the GST vaccine against S. japonicum results from the presence of CD4(+)CD25(+)Foxp3(+) Tregs, while anti-CD25 mAb can partially block CD4(+)CD25(+)Foxp3(+) Tregs and thus enhance the protective efficacy of the GST vaccine.

  10. [Distribution characteristics of deposited eggs and pathological changes in viscera of New Zealand white rabbits infected with Schistosoma japonicum at different time].

    PubMed

    Zhao, Deng-Yun; Xu, Rui; Lin, Jiao-Jiao; Lu, Ke; Hong, Yang; Li, Hao; Liu, Ying-Chun; Liu, Yi-Ping; Zhu, Chuan-gang

    2014-12-01

    To study the distribution characteristics of deposited eggs and pathological changes in the viscera of animal infected with Schistosoma japonicum at different time. New Zealand white rabbits were infected artificially with quantitative S. japonicum miracidia, then the distribution characteristics and the hatchability of schistosome eggs as well as the pathological changes of the corresponding viscera of the rabbits 42 and 60 d post-infection were observed and compared. On the 42nd day post-infection, among all the viscera observed, the percentage of eggs deposited, the number of eggs per gram and the hatchability were the highest in the liver, while on the 60th day post-infection, the tissues and organs with the highest values of the above 3 indexes were the liver, rectum and upper section of the small intestine, respectively. From 42 day to 60 day post-infection, the liver of infected rabbits became swelling, hardening and lost elasticity, the color changed from black to dark grey, and egg nodules gradually appeared in the different sections of the small intestine, and also the mucosal hyperemia, edema and egg nodules were seen in the colon, cecum and rectum. The lesion levels tended to be correlated with the deposition of eggs. The amount and the density as well as the hatching rate of deposited eggs of S. japonicum in the viscera of infected rabbits at different time are different, and the lesion level in the host is correlated with the deposition of eggs.

  11. The dynamic changes of CD3e(-)CD11c(+) dendritic cells in spleens and bone marrow of mice infected with Schistosoma japonicum.

    PubMed

    Chen, Lin; Chen, Qingzhou; Hou, Wei; He, Li

    2017-03-01

    Schistosoma japonicum as a pathogeny requires dendritic cells to activate immune response. So, the research is to study the dynamic changes of CD3e(-)CD11c(+) dendritic cells in mice infected with S. japonicum. Zero, 7, 28, 35, and 63 days were selected to study the variation of dendritic cells, and the proportions of CD3e(-)CD11c(+) dendritic cells and CD86(+) mature dendritic cells in spleens and bone marrow were tested by flow cytometry. As a result, the variation trends of dendritic cells in spleen and bone marrow are similar as follows: the proportions of CD3e(-)CD11c(+) dendritic cells increased first and then decreased from day 35, but the percentages of CD86(+) mature dendritic cells decreased from day 28 and increased in day 63. In vitro, cultured dendritic cells treated with SEA and SAWA were tested by flow cytometry, the variation trends of CD86 on dendritic cells are consistent with the results in days 28 and 63. Besides CD86, the expression of MHC-II also hints immune regulation. In conclusion, it is speculated that dendritic cells play a role of immune regulation through MHC-II and CD86 in S. japonicum infection. Immune regulation of dendritic cells is not only in favor of the survival of host and parasite but also can be used in the therapy for immune diseases.

  12. Ecological Model to Predict Potential Habitats of Oncomelania hupensis, the Intermediate Host of Schistosoma japonicum in the Mountainous Regions, China.

    PubMed

    Zhu, Hong-Ru; Liu, Lu; Zhou, Xiao-Nong; Yang, Guo-Jing

    2015-01-01

    Schistosomiasis japonica is a parasitic disease that remains endemic in seven provinces in the People's Republic of China (P.R. China). One of the most important measures in the process of schistosomiasis elimination in P.R. China is control of Oncomelania hupensis, the unique intermediate host snail of Schistosoma japonicum. Compared with plains/swamp and lake regions, the hilly/mountainous regions of schistosomiasis endemic areas are more complicated, which makes the snail survey difficult to conduct precisely and efficiently. There is a pressing call to identify the snail habitats of mountainous regions in an efficient and cost-effective manner. Twelve out of 56 administrative villages distributed with O. hupensis in Eryuan, Yunnan Province, were randomly selected to set up the ecological model. Thirty out of the rest of 78 villages (villages selected for building model were excluded from the villages for validation) in Eryuan and 30 out of 89 villages in Midu, Yunnan Province were selected via a chessboard method for model validation, respectively. Nine-year-average Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) as well as Digital Elevation Model (DEM) covering Eryuan and Midu were extracted from MODIS and ASTER satellite images, respectively. Slope, elevation and the distance from every village to its nearest stream were derived from DEM. Suitable survival environment conditions for snails were defined by comparing historical snail presence data and remote sensing derived images. According to the suitable conditions for snails, environment factors, i.e. NDVI, LST, elevation, slope and the distance from every village to its nearest stream, were integrated into an ecological niche model to predict O. hupensis potential habitats in Eryuan and Midu. The evaluation of the model was assessed by comparing the model prediction and field investigation. Then, the consistency rate of model validation was calculated in Eryuan and Midu

  13. Ecological Model to Predict Potential Habitats of Oncomelania hupensis, the Intermediate Host of Schistosoma japonicum in the Mountainous Regions, China

    PubMed Central

    Zhu, Hong-Ru; Liu, Lu; Zhou, Xiao-Nong; Yang, Guo-Jing

    2015-01-01

    Background Schistosomiasis japonica is a parasitic disease that remains endemic in seven provinces in the People’s Republic of China (P.R. China). One of the most important measures in the process of schistosomiasis elimination in P.R. China is control of Oncomelania hupensis, the unique intermediate host snail of Schistosoma japonicum. Compared with plains/swamp and lake regions, the hilly/mountainous regions of schistosomiasis endemic areas are more complicated, which makes the snail survey difficult to conduct precisely and efficiently. There is a pressing call to identify the snail habitats of mountainous regions in an efficient and cost-effective manner. Methods Twelve out of 56 administrative villages distributed with O. hupensis in Eryuan, Yunnan Province, were randomly selected to set up the ecological model. Thirty out of the rest of 78 villages (villages selected for building model were excluded from the villages for validation) in Eryuan and 30 out of 89 villages in Midu, Yunnan Province were selected via a chessboard method for model validation, respectively. Nine-year-average Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) as well as Digital Elevation Model (DEM) covering Eryuan and Midu were extracted from MODIS and ASTER satellite images, respectively. Slope, elevation and the distance from every village to its nearest stream were derived from DEM. Suitable survival environment conditions for snails were defined by comparing historical snail presence data and remote sensing derived images. According to the suitable conditions for snails, environment factors, i.e. NDVI, LST, elevation, slope and the distance from every village to its nearest stream, were integrated into an ecological niche model to predict O. hupensis potential habitats in Eryuan and Midu. The evaluation of the model was assessed by comparing the model prediction and field investigation. Then, the consistency rate of model validation was calculated

  14. Estimating sensitivity and specificity of a faecal examination method for Schistosoma japonicum infection in cats, dogs, water buffaloes, pigs, and rats in Western Samar and Sorsogon Provinces, The Philippines.

    PubMed

    Carabin, H; Balolong, E; Joseph, L; McGarvey, S T; Johansen, M V; Fernandez, T; Willingham, A L; Olveda, R

    2005-12-01

    Schistosoma japonicum causes a chronic parasitic disease, which persists as a major public health concern in The Philippines, the People's Republic of China and Indonesia. This infection is unique among helminthic zoonoses because it can infect humans and more than 40 other mammals. The objective of this study was to estimate the sensitivity and specificity of the Danish Bilharziasis Laboratory technique in cats, dogs, pigs, water buffaloes and rats in the Philippines. Faecal samples from each animal were collected on up to five occasions on five consecutive days in four villages of Sorsogon and Western Samar Provinces between January and July 2003. The faecal samples were analysed with the filtration and sedimentation Danish Bilharziasis Laboratory technique. Sensitivity and specificity of one, two, three, four, and five faecal samples were estimated using a Bayesian latent class approach. A total of 59, 43, 74, and 80% of the censored cats, dogs, pigs, and water buffaloes in the four villages were sampled, respectively. For all species, the sensitivity estimates when using the results of only 1 day of sampling were less than 80%. However, the sensitivity improved to at least 96% in all species when three or more faecal samples were collected on three separate days. The specificity was estimated to be above 92% across all species, even if just a single sample is used. The prevalences and 95% credible intervals of S. japonicum, adjusted for imperfect sensitivity and specificity, in cats, dogs, pigs, rats, and water buffaloes were 11.9% (6.8-18.3%), 19.9% (15.1-25.2%), 2.9% (1.1-5.2%), 31.3% (18.3-45.6%) and 6.3% (2.1-12.6%), respectively. Our results suggest that the Danish Bilharziasis Laboratory technique is valid for the detection of infection with S. japonicum in animals, and that sensitivity estimates are excellent when faecal samples are collected on at least three different days. Monitoring S. japonicum infection in animal reservoirs with a valid test could

  15. Evaluation of banked urine samples for the detection of circulating anodic and cathodic antigens in Schistosoma mekongi and S. japonicum infections: a proof-of-concept study.

    PubMed

    van Dam, Govert J; Odermatt, Peter; Acosta, Luz; Bergquist, Robert; de Dood, Claudia J; Kornelis, Dieuwke; Muth, Sinuon; Utzinger, Jürg; Corstjens, Paul L A M

    2015-01-01

    In Asia, Schistosoma japonicum is the predominant schistosome species, while Schistosoma mekongi is confined to limited foci in Cambodia and Lao People's Democratic Republic. While the People's Republic of China has been successful in controlling schistosomiasis, the disease remains a major public health issue in other areas. In order to prioritise intervention areas, not only accurate diagnosis is important but also other factors, such as practicality, time-efficiency and cost-effectiveness, since they strongly influence the success of control programmes. To evaluate the highly specific urine-based assays for the schistosome circulating cathodic antigen (CCA) and the circulating anodic antigen (CAA), banked urine samples from Cambodia (n=106) and the Philippines (n=43) were examined by the upconverted phosphor lateral flow (UCP-LF) CAA assay and the point-of-care (POC)-CCA urine assay. Based on 250 μl urine samples, UCP-LF CAA sensitivity outcomes surpassed a single stool examination by the Kato-Katz technique. The banked urine samples in the current study did not allow the evaluation of larger volumes, which conceivably should deliver considerably higher readings. The sensitivity of a single urine POC-CCA was in the same order as that of a single Kato-Katz thick smear examination, while the sensitivity approached that of triplicate Kato-Katz when a combination of both CAA and CCA assays was used. The promising results from the current proof-of-concept study call for larger investigations that will determine the accuracy of the urine-based CCA and CAA assays for S. mekongi and S. japonicum diagnosis.

  16. Prevalence of Schistosoma japonicum infection of Oncomelania quadrasi snail colonies in 50 irrigated and rain-fed villages of Samar Province, the Philippines

    PubMed Central

    Madsen, Henry; Carabin, Hélène; Balolong, Don; Tallo, Veronica L; Olveda, Remigio; Yuan, M; McGarvey, Stephen T.

    2008-01-01

    A cross-sectional survey of Oncomelania quadrasi, the intermediate host for Schistosoma japonicum, was conducted between 2004 and 2005 in 50 villages of the Province of Samar, the Philippines. The villages were classified as rain-fed (25) or with some man-made irrigation system (25). The primary objective was to identify all snail colony sites in the 50 villages and to compare snail population density and S. japonicum infection prevalence between the two types of villages. The presence of snail colonies was surveyed along streams, springs, various canals and swampy areas or grass land. A total of 198 colony sites were identified out of the 845 sites surveyed. Of these, a sufficient number of O. quadrasi snails were identified to measure density and infection in 147 sites. Density of O. quadrasi was remarkably uniform across habitats and there were no significant differences across habitats and between village type. The prevalence of infected snails showed more variability among habitats. Indeed, there was an interaction between the type of habitat and the type of village with irrigated villages being associated with a prevalence proportion ratio of 5.76 (1.31, 25.42) as compared to rain-fed villages among streams and springs. No such association was found among other habitats. The results suggest that once a suitable habitat exists, O. quadrasi populations establish and reach a plateau density. These results are discussed in light of possible ecological measures of control. PMID:18207119

  17. Comprehensive Transcriptome Analysis of Sex-Biased Expressed Genes Reveals Discrete Biological and Physiological Features of Male and Female Schistosoma japonicum

    PubMed Central

    Piao, Xianyu; Hou, Nan; Gobert, Geoffrey N.; McManus, Donald P.; Chen, Qijun

    2016-01-01

    Schistosomiasis is a chronic and debilitating disease caused by blood flukes (digenetic trematodes) of the genus Schistosoma. Schistosomes are sexually dimorphic and exhibit dramatic morphological changes during a complex lifecycle which requires subtle gene regulatory mechanisms to fulfil these complex biological processes. In the current study, a 41,982 features custom DNA microarray, which represents the most comprehensive probe coverage for any schistosome transcriptome study, was designed based on public domain and local databases to explore differential gene expression in S. japonicum. We found that approximately 1/10 of the total annotated genes in the S. japonicum genome are differentially expressed between adult males and females. In general, genes associated with the cytoskeleton, and motor and neuronal activities were readily expressed in male adult worms, whereas genes involved in amino acid metabolism, nucleotide biosynthesis, gluconeogenesis, glycosylation, cell cycle processes, DNA synthesis and genome fidelity and stability were enriched in females. Further, miRNAs target sites within these gene sets were predicted, which provides a scenario whereby the miRNAs potentially regulate these sex-biased expressed genes. The study significantly expands the expressional and regulatory characteristics of gender-biased expressed genes in schistosomes with high accuracy. The data provide a better appreciation of the biological and physiological features of male and female schistosome parasites, which may lead to novel vaccine targets and the development of new therapeutic interventions. PMID:27128440

  18. Pilot Study on Interferon-γ-producing T Cell Subsets after the Protective Vaccination with Radiation-attenuated Cercaria of Schistosoma japonicum in the Miniature Pig Model

    PubMed Central

    Abdel-Hafeez, Ekhlas Hamed; Watanabe, Kanji; Kamei, Kaori; Kikuchi, Mihoko; Chen, Honggen; Daniel, Boamah; Yu, Chuanxin; Hirayama, Kenji

    2014-01-01

    CLAWN miniature pig has been shown to serve as a suitable host for the experimental infection of Schistosoma japonicum. In this study, we found that radiation-attenuated cercaria (RAC) vaccine gave CLAWN miniature pigs protective immunity against subsequent challenge infection with S. japonicum cercaria. To characterize the protective immune response of the pig model vaccinated by attenuated cercaria, flow cytometric analysis of the reactive T cell subsets was performed. The intracellular interferon (IFN)-γ and the cell surface markers revealed the peripheral blood CD3+ T-lymphocytes produced significant amounts of IFN-γ during the immunization period and after the challenge infection. CD4+ αβ-T cells as well as CD4+/CD8αmid double positive and/or CD8αhigh αβ-T cells were the major IFN-γ-producing CD3+ T cells. On the contrary, γδ T cells did not produce intracellular IFN-γ. Our results suggested that RAC-vaccinated miniature pigs showed effective protective immunity through the activation of αβ T cells bearing antigen specific T-cell receptors but not through the activation of γδ T cells. PMID:25473375

  19. [Expression profiling and immunofluorescence localization of the major egg antigen p40 of Schistosoma japonicum in the liver of infected New Zealand white rabbits].

    PubMed

    Xia, Dan; Deng, Ganming; Teng, Pingying; Xie, Yu; Li, Yaomin; Wang, Chunmei; Chen, Shujie; Chen, Minfang; Mai, Rongjia; Liao, Haiyan; Shi, Lingyu; Ou, Liyan; Chen, Qiwei; Chen, Xiaoguang; Zhou, Xiaohong

    2015-06-01

    To examine the expression profile and immunofluorescence localization of the major egg antigen p40 of Schistosoma japonicum (Sjp40) during granuloma formation in the liver of infected New Zealand white rabbits. New Zealand white rabbits were infected with S. japonicum cercariae, and the livers were harvested at 29 and 45 days post-infection (dpi). The total RNA of the liver tissues was extracted for expression profiling of Sjp40 by quantitative reverse transcription-PCR (qRT-PCR) with GAPDH of S. japonicum as the endogenous reference gene. The expression of Sjp40 in the liver were detected by Western blotting using anti-Sjp40 monoclonal antibody (mAb) 9G7 or anti-Toxoplasma gondii tSAG1 mAb Y3A8 (control) as the primary antibody. Paraffin sections of the liver were prepared for observing egg granuloma formation using HE staining and for indirect immunofluorescence assay of Sjp40 location in the trapped eggs and egg granulomas. The level of Sjp40 mRNA in the eggs trapped in rabbit livers was significantly higher at 45 dpi than that at 29 dpi (P<0.05), and Western blotting confirmed the presence of Sjp40 protein in the rabbit livers at both 29 and 45 dpi. Immunofluorescence assay demonstrated localized expression of Sjp40 in the immature eggs in the rabbit liver at 29 dpi, but at 45 dpi fluorescence was detected in clusters of mature eggs containing miracidium and in the surrounding egg granulomas. The transcriptional levels of Sjp40 significantly increased with the maturation of eggs trapped in the rabbit livers. Sjp40 protein spread from the eggs to the surrounding egg granuloma at 45 dpi when acute liver granulomatous lesions occur, suggesting that Sjp40 plays a key role in egg granulomas formation in the livers of infected New Zealand white rabbits.

  20. PAMAM-Lys, a Novel Vaccine Delivery Vector, Enhances the Protective Effects of the SjC23 DNA Vaccine against Schistosoma japonicum Infection

    PubMed Central

    Wang, Xiaoting; Dai, Yang; Zhao, Song; Tang, Jianxia; Li, Hongjun; Xing, Yuntian; Qu, Guoli; Li, Xinsong; Dai, Jianrong; Zhu, Yinchang; Zhang, Xueguang

    2014-01-01

    Background Schistosomiasis japonica remains a major public-health concern in China. Praziquantel-based chemotherapy effectively reduces both infections and intensity; however, it can not prevent re-infection. Furthermore, there is an increasing concern about praziquantel resistance following long-term repeated use of the drug in endemic areas. Therefore, development of a schistosomiasis vaccine, as a strategy to prevent and control schistosomiasis japonica, has been given high priority. The present study was conducted to develop PAMAM dendrimers as a novel vaccine delivery vector for a schistosomiasis japonica DNA vaccine and evaluate its ability to enhance protective effects against Schistosoma japonicum infection. Methodology/Principal Findings Lysine was used to modify 4.0G PAMAM, and the modified product PAMAM-Lys was synthesized. PAMAM-Lys showed both high transfection and low cytotocity for gene delivery in vitro. DNA vaccines combined with PAMAM-Lys produced higher level of protection compare with naked DNA vaccines against S. japonicum infection in a mouse model. Futhermore,antibodies from mice immunized with PAMAM-Lys combined DNA vaccines were significantly higher than those of mice immunized with the naked DNA vaccines. The PAMAM-Lys vector elicited a predominantly IgG2a antibody response and a tremendously increase in the production of IL-2 and IFN-γ. Conclusion/Significance Lysine-modified PAMAM-Lys is an excellent vector. PAMAM-Lys may enhance the immunoreactivity of DNA vaccine and increase the protective effect of the SjC23 DNA vaccine against S. japonicum infection. PMID:24497955

  1. Immunoglobulin E (IgE) Responses to Paramyosin Predict Resistance to Reinfection with Schistosoma japonicum and Are Attenuated by IgG4▿

    PubMed Central

    Jiz, Mario; Friedman, Jennifer F.; Leenstra, Tjalling; Jarilla, Blanca; Pablo, Archie; Langdon, Gretchen; Pond-Tor, Sunthorn; Wu, Hai-Wei; Manalo, Daria; Olveda, Remigio; Acosta, Luz; Kurtis, Jonathan D.

    2009-01-01

    Schistosomiasis remains a public health concern in developing countries, and rapid reinfection fostered by continued exposure to contaminated water sources necessitates a vaccine to augment current mass treatment-based control strategies. We report isotype-specific (immunoglobulin A [IgA], IgE, IgG1, IgG4, and IgG) antibody responses to soluble worm antigen preparation and the recombinant vaccine candidates rSj97, rSj67, and rSj22 from a Schistosoma japonicum-infected cohort in Leyte, the Philippines, where schistosomiasis is endemic. Sera were collected from infected individuals 1 month posttreatment with praziquantel, and antibody responses were measured using a bead-based multiplex platform. Reinfection was monitored by stool sampling every 3 months, and data up to 1 year were included in the analysis (n = 553). In repeated-measures models, individuals with detectible IgE responses to rSj97 had a 26% lower intensity of reinfection at 12 months posttreatment compared to nonresponders after adjusting for age, gender, village, exposure, pretreatment infection intensity, and clustering by household (P = 0.018). In contrast, IgG4 responses to rSj97 as well as rSj67 and rSj22 were associated with markedly increased reinfection intensity. When stratified by IgG4 and IgE responder status, individuals with IgE but not IgG4 responses to rSj97 (n = 16) had a 77% lower intensity of reinfection at 12 months compared to individuals with IgG4 responses but not IgE responses (n = 274), even after adjusting for potential confounders (P = 0.016). Together with our previously described protective cytokine responses, these data further support paramyosin as a leading vaccine candidate for human schistosomiasis japonica and underscore the importance of careful adjuvant selection to avoid the generation of blocking IgG4 antibody responses. PMID:19273558

  2. Internal versus external determinants of Schistosoma japonicum transmission in irrigated agricultural villages

    PubMed Central

    Spear, Robert C.

    2012-01-01

    Currently schistosomiasis transmission has been suppressed to low levels in many historically endemic areas of China by widespread use of praziquantel in human and bovine populations and application of niclosamide for snail control. However, re-emergent transmission has signalled the need for sustainable interventions beyond these repeated chemical interventions. To take advantage of ongoing investment in rural infrastructure, an index of schistosomiasis transmission potential is needed to identify villages where environmental modifications would be particularly effective. Based on a retrospective analysis of data from 10 villages in Sichuan Province, an index linked to the basic reproductive number is shown to have promise in meeting this need. However, a lack of methods for estimating the spatial components of the proposed metric and for estimating the import of cercariae and miracidia from neighbouring villages leads to significant uncertainty in its estimation. These findings suggest a priority effort to develop methods for measuring the free-swimming forms of the parasite in surface waters. This need is underscored by the high cost and limited sensitivity of current methods for diagnosing human infection and mounting evidence of the inadequacy of snail surveys to identify environments supporting low levels of transmission. PMID:21752808

  3. Schistosoma japonicum-infected hamsters (Mesocricetus auratus) used as a model in experimental chemotherapy with praziquantel, artemether, and OZ compounds.

    PubMed

    Xiao, Shu-hua; Mei, Jing-yan; Jiao, Pei-ying

    2011-02-01

    The purpose of the study is to better understand the antischistosomal properties of artemether, praziquantel, and ozonide (OZ) compounds (synthetic trioxolanes, secondary ozonides) in hamster (Mesocricetus auratus) model. A total of 230 male hamsters infected each with 100 Schistosoma japonicum cercariae were used in the study. Groups of five to ten hamsters were treated orally with artemether, praziquantel, and OZ78 or OZ277 7-35 days post-infection at single doses of 50, 100, 150, or 200 mg/kg. Untreated but infected hamsters in each batch of test served as the control. All treated hamsters were sacrificed 4 weeks post-treatment for collection of residual worms using perfusion technique. Nonparametric method (Mann-Whitney test) was used to analyze the data. In groups of five hamsters treated with artemether 7, 14, 21, 28, and 35 days post-infection at single doses of 150 and 200 mg/kg, the difference of mean worm burden between each treated group and control group was statistically significant (P<0.01). Apart from individual group, no difference in mean worm burden between each two groups of them was seen (P>0.05). Further test with various single doses of 50-200 mg/kg confirmed the similar susceptibility of 7-day-old juvenile and 35-day-old adult schistosomes to artemether. After administration of praziquantel 100 mg/kg to groups of five hamsters 7, 21, and 35 days post-infection, higher worm burden reduction of 95.5% was seen in the group with 35-day-old adult schistosomes while in the groups with 7- and 21-day-old juvenile schistosomes, poor efficacy was seen with mean worm burden reductions of 36.6% and 35.6%. In the same batch of hamster treated with praziquantel 200 mg/kg, the moderate effect of the drug against 7- and 21-day-old worms was seen, but their mean worm burden was significantly higher than that of the group with adult schistosomes. In comparison of artemether and praziquantel against various stages of schistosomes, the results further

  4. Development of Adult Worms and Granulomatous Pathology Are Collectively Regulated by T- and B-Cells in Mice Infected with Schistosoma japonicum

    PubMed Central

    Tang, Hongbin; Ming, Zhenping; Liu, Rong; Xiong, Tao; Grevelding, Christoph G.; Dong, Huifeng; Jiang, Mingsen

    2013-01-01

    Schistosoma blood flukes, which cause schistosomiasis affecting 200 million people in the world, are dependent on signals from host CD4+ T cells to facilitate parasite growth and development in the mammalian host and to induce Th2-biased inflammatory granulomas. B cells, however, are reported to down-regulate granulomatous pathology in schistosomiasis, but not to affect the development of blood flukes together with CD4+ T lymphocytes. Thus it is not clear whether B cells mediate parasite development, reproduction and egg granuloma formation of schistosomes without the help of CD4+ T lymphocytes. Using mice that have severe combined immunodeficiency (scid) and mice lacking T cells (nude), we found that the absence of B cells can more seriously hamper the development and paring of adult worms, but granuloma formation of Schistosoma japonicum in scid mice was not down-regulated comparing with that in nude mice. The level of IL-10 in the sera of nude mice was significantly higher than of scid mice at 43 days post infection (p.i.). Thus multiple mechanisms of immune modulation seem to be involved in parasite development and reproduction by helminth-induced regulatory B cells. Our findings have significance for understanding the molecular connections between schistosomes and T- and B-cells, indicating that more research is needed to develop efficient vaccine-based therapies for schistosomiasis. PMID:23349889

  5. Rapid detection and identification of four major Schistosoma species by high-resolution melt (HRM) analysis.

    PubMed

    Li, Juan; Zhao, Guang-Hui; Lin, RuiQing; Blair, David; Sugiyama, Hiromu; Zhu, Xing-Quan

    2015-11-01

    Schistosomiasis, caused by blood flukes belonging to several species of the genus Schistosoma, is a serious and widespread parasitic disease. Accurate and rapid differentiation of these etiological agents of animal and human schistosomiasis to species level can be difficult. We report a real-time PCR assay coupled with a high-resolution melt (HRM) assay targeting a portion of the nuclear 18S rDNA to detect, identify, and distinguish between four major blood fluke species (Schistosoma japonicum, Schistosoma mansoni, Schistosoma haematobium, and Schistosoma mekongi). Using this system, the Schistosoma spp. was accurately identified and could also be distinguished from all other trematode species with which they were compared. As little as 10(-5) ng genomic DNA from a Schistosoma sp. could be detected. This process is inexpensive, easy, and can be completed within 3 h. Examination of 21 representative Schistosoma samples from 15 geographical localities in seven endemic countries validated the value of the HRM detection assay and proved its reliability. The melting curves were characterized by peaks of 83.65 °C for S. japonicum and S. mekongi, 85.65 °C for S. mansoni, and 85.85 °C for S. haematobium. The present study developed a real-time PCR coupled with HRM analysis assay for detection and differential identification of S. mansoni, S. haematobium, S. japonicum, and S. mekongi. This method is rapid, sensitive, and inexpensive. It has important implications for epidemiological studies of Schistosoma.

  6. Exogenous bone morphogenetic protein-7 reduces hepatic fibrosis in Schistosoma japonicum-infected mice via transforming growth factor-β/Smad signaling

    PubMed Central

    Chen, Bo-Lin; Peng, Jie; Li, Qing-Fu; Yang, Min; Wang, Yuan; Chen, Wei

    2013-01-01

    AIM: To investigate the antifibrotic effects of bone morphogenetic protein-7 (BMP-7) on Schistosoma japonicum (S. japonicum)-induced hepatic fibrosis in BALB/C mice. METHODS: Sixty BALB/C mice were randomly divided into three groups, including a control group (group A, n = 20), model group (group B, n = 20) and BMP-7 treated group (group C, n = 20). The mice in group B and group C were abdominally infected with S. japonicum cercariae to induce a schistosomal hepatic fibrosis model. The mice in group C were administered human recombinant BMP-7. Liver samples were extracted from mice sacrificed at 9 and 15 wk after modeling. Hepatic histopathological changes were assessed using Masson’s staining. Transforming growth factor-beta 1 (TGF-β1), alpha-smooth muscle actin (α-SMA), phosphorylated Smad2/3 (pSmad2/3) and Smad7 protein levels and localization were measured by Western blotting and immunohistochemistry, respectively, and their mRNA expressions were detected by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The schistosomal hepatic fibrosis mouse model was successfully established, as the livers of mice in group B and group C showed varying degrees of typical schistosomal hepatopathologic changes such as egg granuloma and collagen deposition. The degree of collagen deposition in group C was higher than that in group A (week 9: 22.95 ± 6.66 vs 2.02 ± 0.76; week 15: 12.84 ± 4.36 vs 1.74 ± 0.80; P < 0.05), but significantly lower than that in group B (week 9: 22.95 ± 6.66 vs 34.43 ± 6.96; week 15: 12.84 ± 4.36 vs 18.90 ± 5.07; P < 0.05) at both time points. According to immunohistochemistry data, the expressions of α-SMA, TGF-β1 and pSmad2/3 protein in group C were higher than those in group A (α-SMA: week 9: 21.24 ± 5.73 vs 0.33 ± 0.20; week 15: 12.42 ± 4.88 vs 0.34 ± 0.27; TGF-β1: week 9: 37.00 ± 13.74 vs 3.73 ± 2.14; week 15: 16.71 ± 9.80 vs 3.08 ± 2.35; pSmad2/3: week 9: 12.92 ± 4.81 vs 0.83 ± 0.48; week 15: 7.87 ± 4

  7. Combined IL-12 Plasmid and Recombinant SjGST Enhance the Protective and Anti-pathology Effect of SjGST DNA Vaccine Against Schistosoma japonicum.

    PubMed

    Cheng, Po-Ching; Lin, Ching-Nan; Peng, Shih-Yi; Kang, Tsung-Fu; Lee, Kin-Mu

    2016-02-01

    Schistosomiasis is listed as one of most important tropical diseases and more than 200 million people are estimated to be infected. Development of a vaccine is thought to be the most effective way to control this disease. Recombinant 26-kDa glutathione S-transferase (rSjGST) has previously been reported to achieve a worm reduction rate of 42-44%. To improve the efficiency of the vaccine against Schistosoma japonicum, we immunized mice with a combination of pcDNA vector-encoded 26-kDa SjGST (pcDNA/SjGST), IL-12 expressing-plasmid (pIL-12), and rSjGST. Co-vaccination with pcDNA/SjGST, pIL-12, and rSjGST led to a reduction in worm burden, hepatic egg burden, and the size of liver tissue granulomas than that in the untreated infection controls. In addition, we detected high levels of specific IgG, IgG1, and IgG2a against the rSjGST antigen in infected mice vaccinated with this combination of pcDNA/SjGST, pIL-12, and rSjGST. Moreover, high expression levels of Th2 cytokines, including IL-4 and IL-10, were also detected in this group, without diminished levels of IL-12, INF-γ, and TNF-α cytokines that are related to parasite killing. In conclusion, we have developed a new vaccination regimen against S. japonicum infection and shown that co-immunization with pcDNA/SjGST vaccine, pIL-12, and rSjGST has significant anti-parasite, anti-hepatic egg and anti-pathology effects in mice. The efficacy of this vaccination method should be further validated in large animals such as water buffalo. This method may help to reduce the transmission of zoonotic schistosomiasis japonica.

  8. Combined IL-12 Plasmid and Recombinant SjGST Enhance the Protective and Anti-pathology Effect of SjGST DNA Vaccine Against Schistosoma japonicum

    PubMed Central

    Cheng, Po-Ching; Lin, Ching-Nan; Peng, Shih-Yi; Kang, Tsung-Fu; Lee, Kin-Mu

    2016-01-01

    Schistosomiasis is listed as one of most important tropical diseases and more than 200 million people are estimated to be infected. Development of a vaccine is thought to be the most effective way to control this disease. Recombinant 26-kDa glutathione S-transferase (rSjGST) has previously been reported to achieve a worm reduction rate of 42–44%. To improve the efficiency of the vaccine against Schistosoma japonicum, we immunized mice with a combination of pcDNA vector-encoded 26-kDa SjGST (pcDNA/SjGST), IL-12 expressing-plasmid (pIL-12), and rSjGST. Co-vaccination with pcDNA/SjGST, pIL-12, and rSjGST led to a reduction in worm burden, hepatic egg burden, and the size of liver tissue granulomas than that in the untreated infection controls. In addition, we detected high levels of specific IgG, IgG1, and IgG2a against the rSjGST antigen in infected mice vaccinated with this combination of pcDNA/SjGST, pIL-12, and rSjGST. Moreover, high expression levels of Th2 cytokines, including IL-4 and IL-10, were also detected in this group, without diminished levels of IL-12, INF-γ, and TNF-α cytokines that are related to parasite killing. In conclusion, we have developed a new vaccination regimen against S. japonicum infection and shown that co-immunization with pcDNA/SjGST vaccine, pIL-12, and rSjGST has significant anti-parasite, anti-hepatic egg and anti-pathology effects in mice. The efficacy of this vaccination method should be further validated in large animals such as water buffalo. This method may help to reduce the transmission of zoonotic schistosomiasis japonica. PMID:26891172

  9. Characterization of VAMP2 in Schistosoma japonicum and the Evaluation of Protective Efficacy Induced by Recombinant SjVAMP2 in Mice

    PubMed Central

    Han, Qian; Hong, Yang; Fu, Zhiqiang; Zhang, Min; Cao, Xiaodan; Liu, Yantao; Ma, Shuai; Guo, Yuntao; Lu, Ke; Zhu, Chuangang; Lin, Jiaojiao

    2015-01-01

    Background The outer-tegument membrane covering the schistosome is believed to maintain via the fusion of membranous vesicles. Fusion of biological membranes is a fundamental process in all eukaryotic cells driven by formation of trans-SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) complexes through pairing of vesicle associated v-SNAREs (VAMP) with complementary t-SNAREs on target membranes. The purpose of this study was to characterize Schistosoma japonicum vesicle-associated membrane protein 2 (SjVAMP2) and to investigate its potential as a candidate vaccine against schistosomiasis. Methodology/Principal Findings The sequence of SjVAMP2 was analyzed, cloned, expressed and characterized. SjVAMP2 is a member of the synaptobrevin superfamily harboring the v-SNARE coiled-coil homology domain. RT–PCR analysis revealed that significantly higher SjVAMP2 levels were observed in 14-, 28- and 42-day-old worms, and SjVAMP2 expression was much higher in 42-day-old female worms than in those male worms. Additionally, the expression of SjVAMP2 was associated with membrane recovery in PZQ-treated worms. Immunostaining assay showed that SjVAMP2 was mainly distributed in the sub-tegument of the worms. Western blotting revealed that rSjVAMP2 showed strong immunogenicity. Purified rSjVAMP2 emulsified with ISA206 adjuvant induced 41.5% and 27.3% reductions in worm burden, and 36.8% and 23.3% reductions in hepatic eggs in two independent trials. Besides, significantly higher rSjVAMP2-specific IgG, IgG1, IgG2a levels were detected in rSjVAMP2-vaccinated mice. Conclusion Our study indicated that SjVAMP2 is a potential vaccine candidate against S. japonicum and provided the basis for further investigations into the biological function of SjVAMP2. PMID:26641090

  10. Field evaluation of a rapid, visually-read colloidal dye immunofiltration assay for Schistosoma japonicum for screening in areas of low transmission.

    PubMed Central

    Xiao, Xiang; Wang, Tianping; Ye, Hongzhuan; Qiang, Guangxiang; Wei, Haiming; Tian, Zhigang

    2005-01-01

    OBJECTIVE: To determine the validity of a recently developed rapid test--a colloidal dye immunofiltration assay (CDIFA)--used by health workers in field settings to identify villagers infected with Schistosoma japonicum. METHODS: Health workers in the field used CDIFA to test samples from 1553 villagers in two areas of low endemicity and an area where S. japonicum was not endemic in Anhui, China. All the samples were then tested in the laboratory by laboratory staff using a standard parasitological method (Kato-Katz), an indirect haemagglutination assay (IHA), and CDIFA. The results of CDIFA performed by health workers were compared with those obtained by Kato-Katz and IHA. FINDINGS: Concordance between the results of CDIFA performed in field settings and in the laboratory was high (kappa index, 0.95; 95% confidence interval, 0.93-0.97). When Kato-Katz was used as the reference test, the overall sensitivity and specificity of CDIFA were 98.5% and 83.6%, respectively in the two villages in areas of low endemicity, while the specificity was 99.8% in the nonendemic village. Compared with IHA, the overall specificity and sensitivity of CDIFA were greater than 99% and 96%, respectively. With the combination of Kato-Katz and IHA as the reference standard, CDIFA had a sensitivity of 95.8% and a specificity of 99.5%, and an accuracy of 98.6% in the two areas of low endemicity. CONCLUSION: CDIFA is a specific, sensitive, and reliable test that can be used for rapid screening for schistosomiasis by health workers in field settings. PMID:16175827

  11. Recombinant Sj16 from Schistosoma japonicum contains a functional N-terminal nuclear localization signal necessary for nuclear translocation in dendritic cells and interleukin-10 production.

    PubMed

    Sun, Xi; Yang, Fan; Shen, Jia; Liu, Zhen; Liang, Jinyi; Zheng, Huanqin; Fung, Mingchiu; Wu, Zhongdao

    2016-12-01

    Sj16 is a Schistosoma japonicum-derived protein (16 kDa in molecular weight) that has been identified as an immune modulation molecule, but the mechanisms of modulation of immune responses are not known. In this report, we aimed to investigate the host immune regulation mechanism by recombinant Sj16 (rSj16) and thus illuminate the molecular mechanism of immune evasion by S. japonicum. The effect of rSj16 and rSj16 mutants on the biology of dendritic cells (DCs) was assessed by examining DC maturation, cytokine production, and expression of surface markers by flow cytometry and enzyme-linked immunosorbent assay. We found that rSj16 significantly stimulated interleukin (IL)-10 production and inhibited LPS-induced bone marrow-derived dendrite cell (BMDC) maturation in a dose-dependent manner. By using antibody neutralization experiments and IL-10-deficient (knockout) mice, we confirmed that the inhibitory effect of rSj16 on LPS-induced BMDCs is due to its induction of IL-10 production. To understand how rSj16 induces the production of IL-10, we analyzed the protein sequence and revealed two potential nuclear localization signals (NLS) in Sj16. The N-terminal NLS (NLS1) is both necessary and sufficient for translocation of rSj16 to the nucleus of BMDCs and is important for subsequent induction of IL-10 production and the inhibition of BMDC maturation by rSj16. The results of our study concluded that the ability of rSj16 to inhibit DC functions is IL-10 dependent which is operated by IL-10R signal pathway. This study also confirmed that NLS is an important domain associated with increased production of IL-10. Our findings will extend the current understanding on host-schistosome relationship and provide insight about bottleneck of parasitic control.

  12. Cloning of a cDNA encoding SjIrV1, a Schistosoma japonicum calcium-binding protein similar to calnexin, and expression of the recombinant protein in Escherichia coli.

    PubMed

    Hooker, C W; Brindley, P J

    1999-01-11

    Membrane-associated proteins were isolated from adult Philippine strain Schistosoma japonicum by partitioning into the detergent phase of Triton X-114. A rabbit polyclonal antiserum raised against these proteins was used to screen an S. japonicum expression cDNA library. Positive clones were identified which encoded the species orthologue of SmIrV1, a Schistosoma mansoni protein which was initially identified by screening with sera from mice protectively vaccinated with irradiated cercariae [Hawn et al., J. Biol. Chem. 268 (1993) 7692-7698]. The S. japonicum molecule, which we term SjIrV1, is 83% identical to SmIrV1 at the predicted amino acid level and is a member of the calreticulin family of non-EF-hand, calcium-binding proteins. The Chinese strain S. japonicum orthologue of SjIrV1 was obtained by screening with the radiolabelled insert of the Philippine strain clone. Northern blot analysis revealed a single message of around 2.4 kb and gave no indication of alternative splicing. Southern blot analysis gave a simple pattern, indicating a single-copy gene, and showed a single restriction fragment length polymorphism between the genomes of Chinese and Philippine strains of S. japonicum. Recombinant, full-length SjIrV1 was expressed with a hexahistidine tag in Escherichia coli and the recombinant protein isolated by nickel-chelate chromatography. Recombinant SjIrV1 was shown to exhibit calcium-dependent, differential electrophoretic migration and to bind ruthenium red in the absence but not in the presence of calcium ions. The presence of conserved Ca(2+)-binding motifs predicted from the primary sequence, together with the Ca(2+)-dependent electrophoretic mobility of recombinant SjIrV1, confirmed that SjIrV1 was a functional calcium-binding protein.

  13. Schistosoma japonicum in the black rat, Rattus rattus mindanensis, from Leyte, Philippines in relation to Oncomelania snail colonies with reference to other endoparasites.

    PubMed

    Fedorko, J M

    1999-06-01

    This study examined the prevalence of Schistosoma japonicum infections in field rats, Rattus rattus mindanensis, according to different trapping locations. Between October 1995 and January 1996, traps were set in the municipality of Palo, Leyte, Philippines to determine the correlation of rats infected with schistosomiasis to the proximity of the intermediate snail host, Oncomelania hupensis quadrasi, colonies. Of the 22 rats that were caught within a snail colony, 21 (95.5%) were positive for schistosomiasis. Of the 23 rats that were caught 100 meters from a snail colony, 13 (56.5%) were positive for schistosomiasis. Of the 17 rats that were caught approximately 1 km from a snail colony, zero (0%) were positive for schistosomiasis. Infection rates were highest within the habitat of the intermediate host and lowest in rats captured far from snail colonies. Captured rats were also examined for the presence of other endoparasites. Infections of the following were found: Angiostrongylus cantonensis, Gonylonema neoplasticum, Hymenolepis diminuta, Nippostrongylus muris, Strongyloides ratti, Syphacia obvelata, Taenia crassicollis and Trichuris muris, but there was no correlation between trapping location and prevalence. None of the rats were infected with Moniliformis moniliformis, Trichinella spiralis, Trypanosoma lewisi or Vampirolepis nana.

  14. Soluble egg antigens of Schistosoma japonicum induce senescence in activated hepatic stellate cells by activation of the STAT3/p53/p21 pathway

    PubMed Central

    Chen, Jinling; Pan, Jing; Wang, Jianxin; Song, Ke; Zhu, Dandan; Huang, Caiqun; Duan, Yinong

    2016-01-01

    Liver fibrosis is characterized by the activation of hepatic stellate cells (HSCs). Recent findings suggest that senescence of activated HSCs might limit the development of liver fibrosis. Based on previously observed anti-fibrotic effects of soluble egg antigens from Schistosoma japonicum in vitro, we hypothesized that SEA might play a crucial role in alleviating liver fibrosis through promoting senescence of activated HSCs. We show here that SEA inhibited expression of α-SMA and pro-collagen I and promoted senescence of activated HSCs in vitro. In addition, SEA induced an increased expression of P-p53 and p21. Knockdown of p53 inhibited the expression of p21 and failed to induce senescence of activated-HSCs. Phosphorylated STAT3 was elevated upon SEA stimulation, while loss of STAT3 decreased the level of p53 and senescence of HSCs. Results from immunoprecipitation analysis demonstrated that SOCS3 might be involved in the SEA-induced senescence in HSCs through its interaction with p53. This study demonstrates the potential capacity of SEA in restricting liver fibrosis through promoting senescence in HSCs. Furthermore, a novel STAT3-p53-p21 pathway might participate in the observed SEA-mediated senescence of HSCs. Our results suggest that SEA might carry potential therapeutic effects of restraining liver fibrosis through promoting senescence. PMID:27489164

  15. An integrated approach to identify distribution of Oncomelania hupensis, the intermediate host of Schistosoma japonicum, in a mountainous region in China.

    PubMed

    Yang, Kun; Wang, Xian-Hong; Yang, Guo-Jing; Wu, Xiao-Hua; Qi, Yun-Liang; Li, Hong-Jun; Zhou, Xiao-Nong

    2008-07-01

    The aim of this study is to better understand ecological variability related to the distribution of Oncomelania hupensis, the snail intermediate host of Schistosoma japonicum, and predict the spatial distribution of O. hupensis at the local scale in order to develop a more effective control strategy for schistosomiasis in the hilly and mountainous regions of China. A two-pronged approach was applied in this study consisting of a landscape pattern analysis complemented with Bayesian spatial modelling. The parasitological data were collected by cross-sectional surveys carried out in 11 villages in 2006 and mapped based on global positioning system (GPS) coordinates. Environmental surrogates and landscape metrics were derived from remotely-sensed images and land-cover/land-use classification data. Bayesian non-spatial and spatial models were applied to investigate the variation of snail density in relation to environmental surrogates and landscape metrics at the local scale. A Bayesian spatial model, validated by the deviance information criterion (DIC), was found to be the best-fitting model. The mean shape index (MSI) and Shannon's evenness indexes (SEI) were significantly associated with snail density. These findings suggest that decreasing the heterogeneity of the landscape can reduce snail density. A prediction maps were generated by the Bayesian model together with environmental surrogates and landscape metrics. In conclusion, the risk areas of snail distribution at the local scale can be identified using an integrated approach with landscape pattern analysis supported by remote sensing and GIS technologies, as well as Bayesian modelling.

  16. Schistosoma japonicum: screening of cercariae cDNA library by specific single-chain antibody against SIEA26-28 ku and immunization experiment of the recombinant plasmids containing the selected genes.

    PubMed

    Gao, Dong-mei; Wang, Shi-ping; He, Zhuo; Fung, Ming-chiu; Liu, Ming-she; Yu, Lu-xin; Chen, Xiu-chun

    2010-06-01

    To obtain the gene encoding SIEA26-28 ku, which has been proven to be a potential anti-schistosomiasis vaccine candidate, screening Schistosoma japonicum (Sj) cercariae cDNA library with soluble specific single-chain antibody (SIEA26-28 ku-scFv) was performed. A large amount of specific single-chain antibody was harvested through construction of recombinant expression vector pET32a/scFv. The protein was purified and characterized. By using this protein (PET32a-scFv) as a probe, S. japonicum cercariae cDNA library was screened. Two strong positive clones were selected, and their eukaryotic recombinant plasmids were constructed. These genes were named as S. japonicum ribosomal protein S4 (SjRPS4) and S. japonicum ribosomal protein L7 (SjRPL7), respectively. Experiments of mice showed that both SjRPS4 and SjRPL7 DNA vaccines could induce significant immunoprotection. Result of these experiments further proved that the specific single-chain antibody is a very valuable tool in screening of cDNA library to get the corresponding molecules.

  17. The effects of interleukin (IL)-12 and IL-4 deficiency on worm development and granuloma formation in Schistosoma japonicum-infected mice.

    PubMed

    Cheng, Yu-Li; Song, Wen-Jian; Liu, Wen-Qi; Lei, Jia-Hui; Kong, Zheng; Li, Yong-Long

    2012-01-01

    CD4(+) T-helper (Th) cell is widely recognized to be capable of influencing worm development and egg granuloma formation after schistosome infection. Interleukin (IL)-12 and IL-4 play key roles in regulation of Th cell differentiation. In the present study, we subcutaneously inoculated mice with hybridoma cells secreting monoclonal antibodies to neutralize IL-12 and IL-4 and explored the effects of IL-12 and IL-4 deficiency on the worm development and granuloma formation in mice infected with cercariae of Schistosoma japonicum. It was found that deficiency of host IL-12 and IL-4 supported normal parasite survival and fecundity. However, worm development (length and female fecundity) was significantly enhanced in anti-IL-12-treated mice. Mean length of worms in anti-IL-12-treated group was significantly greater than that of intact controls on day 28 after infection (females, 11.84 ± 1.20 mm vs. 9.45 ± 1.34; males, 9.35 ± 1.21 mm vs. 8.10 ± 0.85 mm, p < 0.05). Liver egg load per pair of worms (1,770.12 ± 470.67 vs. 806.08 ± 232.37, p < 0.05) and uterine egg load of ovigerous females (93.08 ± 27.85 vs. 46.05 ± 34.24, p < 0.05) in anti-IL-12-treated mice were significantly higher than those in intact control 28 days postinfection. But these effects diminished 42 days postinfection (p > 0.05). Granuloma size in anti-IL-12-treated mice was significantly larger than that in intact mice 42 days postinfection (398.3 ± 80.7 μm vs. 294.4 ± 72.2 μm, p < 0.05). Granuloma fibrosis dramatically intensified in anti-IL-12-treated mice but diminished in anti-IL-4-treated mice. The results suggest that IL-12 may play an impeditive role in the development of S. japonicum and in granuloma formation as well as fibrosis. IL-4 may promote granuloma formation but have no effect on worm development.

  18. Evidence That Rhesus Macaques Self-Cure from a Schistosoma japonicum Infection by Disrupting Worm Esophageal Function: A New Route to an Effective Vaccine?

    PubMed Central

    Li, Xiao-Hong; Xu, Yu-Xin; Vance, Gill; Wang, Yun; Lv, Long-Bao; van Dam, Govert J.; Cao, Jian-Ping; Wilson, R. Alan

    2015-01-01

    Background Rhesus macaques are unusual among schistosome hosts, self-curing from an established infection and thereafter manifesting solid immunity against a challenge, an ideal model for vaccine development. Previously, the immunological basis of self-cure was confirmed; surviving worms had ceased feeding but how immunological pressure achieved this was unclear. The schistosome esophagus is not simply a conduit for blood but plays a central role in its processing. Secretions from the anterior and posterior esophageal glands mix with incoming blood causing erythrocyte lysis and tethering and killing of leucocytes. Methodology/Principal Findings We have analysed the self-cure process in rhesus macaques infected with Schistosoma japonicum. Faecal egg output and circulating antigen levels were used to chart the establishment of a mature worm population and its subsequent demise. The physiological stress of surviving females at perfusion was especially evident from their pale, shrunken appearance, while changes in the structure and function of the esophagus were observed in both sexes. In the anterior region electron microscopy revealed that the vesicle secretory process was disrupted, the tips of lining corrugations being swollen by greatly enlarged vesicles and the putative sites of vesicle release obscured by intense deposits of IgG. The lumen of the posterior esophagus in starving worms was occluded by cellular debris and the lining cytoplasmic plates were closely adherent, also potentially preventing secretion. Seven proteins secreted by the posterior gland were identified and IgG responses were detected to some or all of them. Intrinsic rhesus IgG colocalized with secreted SjMEGs 4.1, 8.2, 9, 11 and VAL-7 on cryosections, suggesting they are potential targets for disruption of function. Conclusions/Significance Our data suggest that rhesus macaques self-cure by blocking esophagus function with antibody; the protein products of the glands provide a new class of

  19. Rapid, simple, and sensitive immunoagglutination assay with SiO2 particles and quartz crystal microbalance for quantifying Schistosoma japonicum antibodies.

    PubMed

    Wang, Hua; Zhang, Yun; Yan, Bani; Liu, Li; Wang, Shiping; Shen, Guoli; Yu, Ruqin

    2006-11-01

    The resurgence of the parasitic disease schistosomiasis calls for more efficient diagnostic tests. We developed a rapid, simple, portable, and sensitive immunoagglutination assay that uses SiO(2) particles and quartz crystal microbalance (QCM) for quantifying Schistosoma japonicum (Sj) antibodies (SjAb). We prepared submicrometer-sized silica particles derivatized with Sj antigens as replacements for traditional latex microspheres to specifically agglutinate in the presence of SjAb targets, and we used the QCM monitor to measure the resulting frequency shifts. We optimized the assay medium by adding poly(ethylene glycol) (PEG) as a response accelerator of immunoagglutination. To minimize or eliminate any nonspecific agglutination or adsorption interferences, we conducted appropriate sealing procedures separately for silica particles and the QCM probe. The measured frequency changes were linearly related to the SjAb concentrations in infected rabbit serum. The PEG-assisted immunoagglutination system was quantitatively sensitive to SjAb concentrations ranging from approximately 0.70 to 32.31 mg/L, with a detection limit of approximately 0.46 mg/L. The obtained linear regression equation was: y=43.61 x+80.44 (r=0.9872). Several serum specimens were evaluated with the developed QCM immunoassay and the results were compared with ELISA, validating the feasibility of practical applications. This novel immunoagglutination-based QCM detection format is rapid, simple to use, and more portable than conventional diagnostic immunoassays, thus offering a promising alternative tool that can be used for point-of-care clinical diagnosis of schistosomiasis, particularly in epidemic situations.

  20. Generation of a Novel Bacteriophage Library Displaying scFv Antibody Fragments from the Natural Buffalo Host to Identify Antigens from Adult Schistosoma japonicum for Diagnostic Development

    PubMed Central

    Hosking, Christopher G.; McWilliam, Hamish E. G.; Driguez, Patrick; Piedrafita, David; Li, Yuesheng; McManus, Donald P.; Ilag, Leodevico L.; Meeusen, Els N. T.; de Veer, Michael J.

    2015-01-01

    The development of effective diagnostic tools will be essential in the continuing fight to reduce schistosome infection; however, the diagnostic tests available to date are generally laborious and difficult to implement in current parasite control strategies. We generated a series of single-chain antibody Fv domain (scFv) phage display libraries from the portal lymph node of field exposed water buffaloes, Bubalus bubalis, 11–12 days post challenge with Schistosoma japonicum cercariae. The selected scFv-phages showed clear enrichment towards adult schistosomes and excretory-secretory (ES) proteins by immunofluorescence, ELISA and western blot analysis. The enriched libraries were used to probe a schistosome specific protein microarray resulting in the recognition of a number of proteins, five of which were specific to schistosomes, with RNA expression predominantly in the adult life-stage based on interrogation of schistosome expressed sequence tags (EST). As the libraries were enriched by panning against ES products, these antigens may be excreted or secreted into the host vasculature and hence may make good targets for a diagnostic assay. Further selection of the scFv library against infected mouse sera identified five soluble scFv clones that could selectively recognise soluble whole adult preparations (SWAP) relative to an irrelevant protein control (ovalbumin). Furthermore, two of the identified scFv clones also selectively recognised SWAP proteins when spiked into naïve mouse sera. These host B-cell derived scFvs that specifically bind to schistosome protein preparations will be valuable reagents for further development of a cost effective point-of-care diagnostic test. PMID:26684756

  1. Linalool, derived from Cinnamomum camphora (L.) Presl leaf extracts, possesses molluscicidal activity against Oncomelania hupensis and inhibits infection of Schistosoma japonicum.

    PubMed

    Yang, Fan; Long, Erping; Wen, Juhua; Cao, Lei; Zhu, Chengcheng; Hu, Huanxin; Ruan, Ying; Okanurak, Kamolnetr; Hu, Huiling; Wei, Xiaoxia; Yang, Xiangyun; Wang, Chaofan; Zhang, Limei; Wang, Xiaoying; Ji, Pengyu; Zheng, Huanqin; Wu, Zhongdao; Lv, Zhiyue

    2014-08-29

    Schistosomiasis japonicum remains a considerable economic and public health concern in China, the Philippines and Indonesia. Currently available measures to control the unique intermediate host Oncomelania hupensis are frequently associated with severe side effects. Previous studies have demonstrated that linalool-rich extracts from various plants exhibited promising biological activities including cytotoxic, anti-microbial and anti-parasitic properties. We identified the components of leaf extracts from Cinnamomum camphora by gas chromatography coupled to mass spectrometry (GC-MS) and investigated molluscicidal and larvicidal effects of linalool against O. hupensis and Schistosoma japonicium. The ultrastructural alterations in gills, salivary gland, stomach and hepatopancreas of snails were observed under the light microscope and transmission electron microscope, and lesions to tegument of cercaria were examined under a light microscope and fluorescence microscope. We then evaluated the effects of linalool on skin penetration and migration of schistosomula and adult survival by measurement of worm burden and egg counts in Balb/C mice infected with linalool-treated cercariae. In the present work, 44 components were identified from the leaf extracts of C. camphora, of which linalool was the most abundant constituent. Linalool exhibited the striking molluscicidal and larvicidal effects with LC50 = 0.25 mg/L for O. hupensis and LC50 = 0.07 mg/L for cercaria of S. japonicium. After exposure to linalool, damage to the gills and hepatopancreas of the snails, and to the tegument and body-tail joint of cercariae was apparent. In addition, linalool markedly reduced the recovered schistosomulum from mouse skin after challenge infection, and therefore decreased the worm burden in infected animals, but not fecundity of female adults of the parasite. Our findings indicated that linalool might be a novel chemotherapeutic agent against S. japonicium and the snail

  2. Evidence That Rhesus Macaques Self-Cure from a Schistosoma japonicum Infection by Disrupting Worm Esophageal Function: A New Route to an Effective Vaccine?

    PubMed

    Li, Xiao-Hong; Xu, Yu-Xin; Vance, Gill; Wang, Yun; Lv, Long-Bao; van Dam, Govert J; Cao, Jian-Ping; Wilson, R Alan

    2015-01-01

    Rhesus macaques are unusual among schistosome hosts, self-curing from an established infection and thereafter manifesting solid immunity against a challenge, an ideal model for vaccine development. Previously, the immunological basis of self-cure was confirmed; surviving worms had ceased feeding but how immunological pressure achieved this was unclear. The schistosome esophagus is not simply a conduit for blood but plays a central role in its processing. Secretions from the anterior and posterior esophageal glands mix with incoming blood causing erythrocyte lysis and tethering and killing of leucocytes. We have analysed the self-cure process in rhesus macaques infected with Schistosoma japonicum. Faecal egg output and circulating antigen levels were used to chart the establishment of a mature worm population and its subsequent demise. The physiological stress of surviving females at perfusion was especially evident from their pale, shrunken appearance, while changes in the structure and function of the esophagus were observed in both sexes. In the anterior region electron microscopy revealed that the vesicle secretory process was disrupted, the tips of lining corrugations being swollen by greatly enlarged vesicles and the putative sites of vesicle release obscured by intense deposits of IgG. The lumen of the posterior esophagus in starving worms was occluded by cellular debris and the lining cytoplasmic plates were closely adherent, also potentially preventing secretion. Seven proteins secreted by the posterior gland were identified and IgG responses were detected to some or all of them. Intrinsic rhesus IgG colocalized with secreted SjMEGs 4.1, 8.2, 9, 11 and VAL-7 on cryosections, suggesting they are potential targets for disruption of function. Our data suggest that rhesus macaques self-cure by blocking esophagus function with antibody; the protein products of the glands provide a new class of potential vaccine targets.

  3. Effect of mefloquine administered orally at single, multiple, or combined with artemether, artesunate, or praziquantel in treatment of mice infected with Schistosoma japonicum.

    PubMed

    Xiao, Shu-hua; Mei, Jing-yan; Jiao, Pei-ying

    2011-02-01

    The purpose of the study is to explore the efficacy of mefloquine administered orally at single, multiple doses, or in combination with artesuante, artemether, or praziquantel in mouse--Schistosoma japonicum model. A total of 205 mice were divided into 4 batches and each batch of mice was infected percutaneously with 40 S. japonicum cercariae for 35 days. The infected mice were treated orally with mefloquine at single doses, multiple daily doses, or combined with artesunate, artemether, or praziquantel, while infected but untreated mice served as control. All treated animals were killed 4 weeks post-treatment for assessment of effect. When infected mice were treated orally with mefloquine at single or multiple daily doses under the same total dose levels, the tendency to decrease the efficacy was seen. Particularly, when a lower single dose of 100 mg/kg was divided equally into five daily doses of 20 mg/kg, the efficacy decreased statistically significant (P<0.05), i.e., the total worm and female worm reductions of 67.9% and 73.4% decreased to 31.3% and 30.3%, respectively. In infected mice treated with mefloquine or artesuante at a single dose of 100 mg/kg, a moderate effect against schistosomes was observed. No further significant reduction of total and female worm burdens was seen, when the two drugs combined together at the same dose level. On the other hand, administration of mefloquine combined with artesunate at single dose of 50 mg/kg, which exhibited no effect against schistosomes, resulted in significant reduction of total and female worm burdens in comparison with the groups treated with mefloquine and artesunate alone at the same dose level. Similar results were observed in treatment of infected mice with mefloquine in combination with artemether at the smaller dose of 50 mg/kg. The total worm burden was significantly lower than that of control and the female worm burden was also significant lower than that of groups treated with mefloquine and

  4. Genetic Evidence of Contemporary Dispersal of the Intermediate Snail Host of Schistosoma japonicum: Movement of an NTD Host Is Facilitated by Land Use and Landscape Connectivity

    PubMed Central

    Chang, Howard; Li, Qunna; Hoover, Christopher M.; Wilke, Thomas; Clewing, Catharina; Carlton, Elizabeth J.; Liang, Song; Lu, Ding; Zhong, Bo; Remais, Justin V.

    2016-01-01

    Background While the dispersal of hosts and vectors—through active or passive movement—is known to facilitate the spread and re-emergence of certain infectious diseases, little is known about the movement ecology of Oncomelania spp., intermediate snail host of the parasite Schistosoma japonicum, and its consequences for the spread of schistosomiasis in East and Southeast Asia. In China, despite intense control programs aimed at preventing schistosomiasis transmission, there is evidence in recent years of re-emergence and persistence of infection in some areas, as well as an increase in the spatial extent of the snail host. A quantitative understanding of the dispersal characteristics of the intermediate host can provide new insights into the spatial dynamics of transmission, and can assist public health officials in limiting the geographic spread of infection. Methodology/Principal findings Oncomelania hupensis robertsoni snails (n = 833) were sampled from 29 sites in Sichuan, China, genotyped, and analyzed using Bayesian assignment to estimate the rate of recent snail migration across sites. Landscape connectivity between each site pair was estimated using the geographic distance distributions derived from nine environmental models: Euclidean, topography, incline, wetness, land use, watershed, stream use, streams and channels, and stream velocity. Among sites, 14.4% to 32.8% of sampled snails were identified as recent migrants, with 20 sites comprising >20% migrants. Migration rates were generally low between sites, but at 8 sites, over 10% of the overall host population originated from one proximal site. Greater landscape connectivity was significantly associated with increased odds of migration, with the minimum path distance (as opposed to median or first quartile) emerging as the strongest predictor across all environmental models. Models accounting for land use explained the largest proportion of the variance in migration rates between sites. A greater

  5. Metabonomic investigation of human Schistosoma mansoni infection.

    PubMed

    Balog, Crina I A; Meissner, Axel; Göraler, Sibel; Bladergroen, Marco R; Vennervald, Birgitte J; Mayboroda, Oleg A; Deelder, André M

    2011-05-01

    Schistosomiasis is a parasitic infection that is endemic in many developing countries in the tropics and subtropics afflicting more than 207 million people primarily in rural areas. After malaria, it is the second most important parasitic infection in terms of socio-economic and public health. Investigation of the host-parasite interaction at the molecular level and identification of biomarkers of infection and infection-related morbidity would be of value for improved strategies for treatment and morbidity control. To this end, we conducted a nuclear magnetic resonance (NMR) based metabonomics study involving a well-characterized cohort of 447 individuals from a rural area in Uganda near Lake Victoria with a high prevalence of Schistosoma mansoni, a species predominantly occurring in Africa including Madagascar and parts of South America. Cohort samples were collected from individuals at five time-points, before and after (one or two times) chemotherapy with praziquantel (PZQ). Using supervised multivariate statistical analysis of the recorded one-dimensional (1D) NMR spectra, we were able to discriminate infected from uninfected individuals in two age groups (children and adults) based on differences in their urinary profiles. The potential molecular markers of S. mansoni infection were found to be primarily linked to changes in gut microflora, energy metabolism and liver function. These findings are in agreement with data from earlier studies on S. mansoni infection in experimental animals and thus provide corroborating evidence for the existence of metabolic response specific for this infection.

  6. The genome of a blood fluke associated with human cancer

    PubMed Central

    Mitreva, Makedonka

    2013-01-01

    The sequencing of the genome and transcriptome of Schistosoma haematobium, a highly prevalent blood fluke and human parasite with a proven link to malignant bladder cancer, marks the 160th anniversary of its discovery as the first schistosome known to infect humans. Comparative genomic analyses of S. haematobium and the more prevalent human-schistosomiasis pathogens (Schistosoma mansoni and Schistosoma japonicum) identified both shared and distinct genomic features. PMID:22281765

  7. Significance of higher drug concentration in erythrocytes of mice infected with Schistosoma japonicum and treated orally with mefloquine at single doses.

    PubMed

    Tao, Yi; Xue, Jian; Jiang, Bin; Zhang, Hao-Bing; Xiao, Shu-Hua

    2015-12-01

    The purpose of the present study is to understand the pharmacokinetic feature of mefloquine measured by erythrocytes and plasma in Schistosoma japonicum (S. j.)-infected mice and non-infected mice after oral administration of the drug at single doses. A high-performance liquid chromatography (HPLC) method was used to measure the plasma and erythrocyte concentrations of mefloquine at varying intervals posttreatment. Our results demonstrated that in non-infected mice treated orally with mefloquine at an ineffective dose of 50 mg/kg or effective dose of 200 mg/kg for 2-72 h, the erythrocyte-to-plasma ratios of mefloquine were 5.8-11.2 or 2-14.2. On the other hand, in S. j.-infected mice treated with the same single doses of the drug, the erythrocyte and plasma drug concentration ratios were 3.1-4.6 or 2.9-8.5, manifesting that either in infected mice or in non-infected mice that received oral mefloquine resulted in higher concentration of mefloquine in erythrocytes than that in plasma. Unexpectedly, under oral administration of mefloquine at a higher single dose of 200 mg/kg, the pharmacokinetic parameter C max values for plasma from S. j.-infected and non-infected mice were 1.6 ± 0.3 and 2.0 ± 0.4 μg/mL, respectively, which were below the determined in vitro LC50 (50 % lethal concentration) value of 4.93 μg/mL. Therefore, the plasma concentration of mefloquine may display a little effect against schistosomes during the treatment. Although the values of T 1/2 and AUC0-∞ for erythrocytes were significantly longer and higher in infected mice than those of corresponding non-infect mice that received the same single mefloqine dose of 50 mg/kg, the C max value was only 2.6 ± 0.4 μg/mL lower than the determined in vitro LC50, which may explain why this low single dose is ineffective against schistosomes in vivo. After administration of higher mefloquine dose of 200 mg/kg, the C max value for erythrocytes in infected mice was 30 % (7.4 ± 0

  8. Novel expression profiles of microRNAs suggest that specific miRNAs regulate gene expression for the sexual maturation of female Schistosoma japonicum after pairing

    PubMed Central

    2014-01-01

    Background Schistosoma japonicum is one of the major causative agents of schistosomiasis. The pairing of males and females leads to female sexual maturation and maintains this mature state. However, the mechanisms by which pairing facilitates sexual maturation are yet to be investigated. Methods Parasites isolated from single- and double-sex cercariae-infected mice were analyzed by Solexa to uncover pair-regulated miRNA profiles. To reveal the biological functions of differentially expressed miRNAs among the samples, we predicted the target genes of these differentially expressed miRNAs and compared the gene expression between 23-d-old female schistosomula from double-sex infections (23DSI) and 23-d-old female schistosomula from single-sex infections (23SSI) by analyzing digital gene expression profiling (DGE). KEGG pathway analysis was used to investigate the relevant biological processes of these target genes to understand the significance of differentially expressed miRNAs after pairing. Results The differentially expressed miRNA profiles of female 18- and 23-d post-single- and double-sex infections were analysed by Solexa. Similar miRNA profiles were observed in 18SSI and 18DSI, with the presence of identically expressed high-abundance miRNA, such as miRNA-1, miRNA-71b-5p and let-7. By contrast, in 23DSI and 23SSI, most of these high-abundance miRNAs were down-regulated. Furthermore, among all samples, bantam was distinctly up-regulated in 23 DSI, and miR-1, miR-71, miR-7-5p, and miR-7 were distinctly up-regulated in 23SSI. The transcriptomes of 23DSI and 23SSI revealed that the predicted target genes of miRNA-1, miRNA-71, miRNA-7, and miR-7-5p were associated with the ribonucleoprotein complex assembly and microtubule-based process. Conversely, the predicted target genes of bantam were related to the embryo development, development of primary sexual characteristics and regulation of transcription. KEGG pathway analysis revealed that in unpaired females, the

  9. Spatio-temporal analysis to identify determinants of Oncomelania hupensis infection with Schistosoma japonicum in Jiangsu province, China

    PubMed Central

    2013-01-01

    Background With the successful implementation of integrated measures for schistosomiasis japonica control, Jiangsu province has reached low-endemicity status. However, infected Oncomelania hupensis snails could still be found in certain locations along the Yangtze river until 2009, and there is concern that they might spread again, resulting in the possible re-emergence of infections among people and domestic animals alike. In order to establish a robust surveillance system that is able to detect the spread of infected snails at an early stage, sensitive and reliable methods to identify risk factors for the establishment of infected snails need to be developed. Methods A total of 107 villages reporting the persistent presence of infected snails were selected. Relevant data on the distribution of infected snails, and human and livestock infection status information for the years 2003 to 2008 were collected. Spatio-temporal pattern analysis including spatial autocorrelation, directional distribution and spatial error models were carried out to explore spatial correlations between infected snails and selected explanatory factors. Results The area where infected snails were found, as well as their density, decreased significantly between 2003 and 2008. Changes in human and livestock prevalences were less pronounced. Three statistically significant spatial autocorrelations for infected snails were identified. (i) The Moran’s I of infected snails increased from 2004 to 2007, with the snail density increasing and the area with infected snails decreasing. (ii) The standard deviations of ellipses around infected snails were decreasing and the central points of the ellipses moved from West to East. (iii) The spatial error models indicated no significant correlation between the density of infected snails and selected risk factors. Conclusions We conclude that the contribution of local infection sources including humans and livestock to the distribution of infected snails

  10. Exposure versus Susceptibility as Alternative Bases for New Approaches to Surveillance for Schistosoma japonicum in Low Transmission Environments.

    PubMed

    Wang, Shuo; Spear, Robert C

    2016-03-01

    Currently, schistosomiasis in China provides an excellent example of many of the challenges of moving from low transmission to the elimination of transmission for infectious diseases generally. In response to the surveillance dimension of these challenges, we here explore two strategic approaches to inform priorities for the development of improved methods addressed specifically to schistosomiasis in the low transmission environment. We utilize an individually-based model and the exposure data used earlier to explore surveillance strategies, one focused on exposure assessment and the second on our estimates of variability in individual susceptibility in the practical context of the current situation in China and the theoretical context of the behavior of transmission dynamics near the zero state. Our findings suggest that individual susceptibility is the major single determinant of infection intensity in both the low and medium risk environments. We conclude that there is considerable motivation to search for a biomarker of susceptibility to infection in humans, but that there would also be value in a method for monitoring surface waters for the free-swimming forms of the parasite in endemic or formerly endemic environments as an early warning of infection risk.

  11. Local Immune Responses of the Chinese Water Buffalo, Bubalus bubalis, against Schistosoma japonicum Larvae: Crucial Insights for Vaccine Design

    PubMed Central

    McWilliam, Hamish E. G.; Piedrafita, David; Li, Yuesheng; Zheng, Mao; He, Yongkang; Yu, Xinling; McManus, Donald P.; Meeusen, Els N. T.

    2013-01-01

    Asian schistosomiasis is a zoonotic parasitic disease infecting up to a million people and threatening tens of millions more. Control of this disease is hindered by the animal reservoirs of the parasite, in particular the water buffalo (Bubalus bubalis), which is responsible for significant levels of human transmission. A transmission-blocking vaccine administered to buffaloes is a realistic option which would aid in the control of schistosomiasis. This will however require a better understanding of the immunobiology of schistosomiasis in naturally exposed buffaloes, particularly the immune response to migrating schistosome larvae, which are the likely targets of an anti-schistosome vaccine. To address this need we investigated the immune response at the major sites of larval migration, the skin and the lungs, in previously exposed and re-challenged water buffaloes. In the skin, a strong allergic-type inflammatory response occurred, characterised by leukocyte and eosinophil infiltration including the formation of granulocytic abscesses. Additionally at the local skin site, interleukin-5 transcript levels were elevated, while interleukin-10 levels decreased. In the skin-draining lymph node (LN) a predominant type-2 profile was seen in stimulated cells, while in contrast a type-1 profile was detected in the lung draining LN, and these responses occurred consecutively, reflecting the timing of parasite migration. The intense type-2 immune response at the site of cercarial penetration is significantly different to that seen in naive and permissive animal models such as mice, and suggests a possible mechanism for immunity. Preliminary data also suggest a reduced and delayed immune response occurred in buffaloes given high cercarial challenge doses compared with moderate infections, particularly in the skin. This study offers a deeper understanding into the immunobiology of schistosomiasis in a natural host, which may aid in the future design of more effective vaccines

  12. The affinity of magnetic microspheres for Schistosoma eggs.

    PubMed

    Candido, Renata R F; Favero, Vivian; Duke, Mary; Karl, Stephan; Gutiérrez, Lucía; Woodward, Robert C; Graeff-Teixeira, Carlos; Jones, Malcolm K; St Pierre, Timothy G

    2015-01-01

    Schistosomiasis is a chronic parasitic disease of humans, with two species primarily causing the intestinal infection: Schistosoma mansoni and Schistosoma japonicum. Traditionally, diagnosis of schistosomiasis is achieved through direct visualisation of eggs in faeces using techniques that lack the sensitivity required to detect all infections, especially in areas of low endemicity. A recently developed method termed Helmintex™ is a very sensitive technique for detection of Schistosoma eggs and exhibits 100% sensitivity at 1.3 eggs per gram of faeces, enough to detect even low-level infections. The Helminthex™ method is based on the interaction of magnetic microspheres and schistosome eggs. Further understanding the underlying egg-microsphere interactions would enable a targeted optimisation of egg-particle binding and may thus enable a significant improvement of the Helmintex™ method and diagnostic sensitivity in areas with low infection rates. We investigated the magnetic properties of S. mansoni and S. japonicum eggs and their interactions with microspheres with different magnetic properties and surface functionalization. Eggs of both species exhibited higher binding affinity to the magnetic microspheres than the non-magnetic microspheres. Binding efficiency was further enhanced if the particles were coated with streptavidin. Schistosoma japonicum eggs bound more microspheres compared with S. mansoni. However, distinct differences within eggs of each species were also observed when the distribution of the number of microspheres bound per egg was modelled with double Poisson distributions. Using this approach, both S. japonicum and S. mansoni eggs fell into two groups, one having greater affinity for magnetic microspheres than the other, indicating that not all eggs of a species exhibit the same binding affinity. Our observations suggest that interaction between the microspheres and eggs is more likely to be related to surface charge-based electrostatic

  13. Cercarial glycocalyx of Schistosoma mansoni activates human complement.

    PubMed Central

    Samuelson, J C; Caulfield, J P

    1986-01-01

    Human complement activation by cercariae and schistosomula of the human parasite Schistosoma mansoni was studied in vitro. Cercariae are composed of tails which are shed after infection of the host and bodies which transform into the larvae or schistosomula after infection. After incubation in fresh normal human serum (NHS), cercarial tails bound more anti-C3 antibodies than did cercarial bodies (CB), and the tails were rapidly lysed, while the attached CB remained intact. Complement activation by cercariae was dependent on the alternative pathway but was independent of antibody, as shown by C3 deposition by hypogammaglobulinemic human sera. By transmission microscopy, the fibrillar glycocalyx on both CB and tails was stained by NHS but not by heat-inactivated serum (HI-NHS). The glycocalyx was labeled with periodate and tritiated borohydride, and parasites were incubated in NHS and HI-NHS. After solubilization, the labeled glycocalyx on organisms incubated in NHS but not HI-NHS bound anti-C3 antibodies. Of the CB incubated with eserine sulfate to prevent transformation, 78% +/- 10% were dead after culture for 24 h in NHS. In contrast, 21% +/- 12% of the CB were dead after culture in HI-NHS. Schistosomula incubated in NHS bound 37% of the amount of anti-C3 antibodies bound by cercariae but were not killed by NHS. In conclusion, the cercarial glycocalyx activated human complement, and schistosomula were less susceptible to killing than cercariae because they had less glycocalyx and activated less complement. Images PMID:3940995

  14. Microarray Analysis of Gene Expression Profiles of Schistosoma japonicum Derived from Less-Susceptible Host Water Buffalo and Susceptible Host Goat

    PubMed Central

    Yang, Jianmei; Hong, Yang; Yuan, Chunxiu; Fu, Zhiqiang; Shi, Yaojun; Zhang, Min; Shen, Liuhong; Han, Yanhui; Zhu, Chuangang; Li, Hao; Lu, Ke; Liu, Jinming; Feng, Xingang; Lin, Jiaojiao

    2013-01-01

    Background Water buffalo and goats are natural hosts for S. japonicum in endemic areas of China. The susceptibility of these two hosts to schistosome infection is different, as water buffalo are less conducive to S. japonicum growth and development. To identify genes that may affect schistosome development and survival, we compared gene expression profiles of schistosomes derived from these two natural hosts using high-throughput microarray technology. Results The worm recovery rate was lower and the length and width of worms from water buffalo were smaller compared to those from goats following S. japonicum infection for 7 weeks. Besides obvious morphological difference between the schistosomes derived from the two hosts, differences were also observed by scanning and transmission electron microscopy. Microarray analysis showed differentially expressed gene patterns for parasites from the two hosts, which revealed that genes related to lipid and nucleotide metabolism, as well as protein folding, sorting, and degradation were upregulated, while others associated with signal transduction, endocrine function, development, immune function, endocytosis, and amino acid/carbohydrate/glycan metabolism were downregulated in schistosomes from water buffalo. KEGG pathway analysis deduced that the differentially expressed genes mainly involved lipid metabolism, the MAPK and ErbB signaling pathways, progesterone-mediated oocyte maturation, dorso-ventral axis formation, reproduction, and endocytosis, etc. Conclusion The microarray gene analysis in schistosomes derived from water buffalo and goats provide a useful platform to disclose differences determining S. japonicum host compatibility to better understand the interplay between natural hosts and parasites, and identify schistosome target genes associated with susceptibility to screen vaccine candidates. PMID:23940568

  15. Eosinophil chemotactic lymphokine produced by spleen cells of Schistosoma japonicum-infected mice. III. Isolation and characterization of two distinctive eosinophil chemotactic lymphokines directed against different maturation stages of eosinophils.

    PubMed

    Owhashi, M; Nawa, Y

    1987-01-01

    Two distinctive types of eosinophil chemotactic lymphokines (ECF-L) directed against eosinophils obtained from bone marrow (BM-Eo) or from peritoneal cavity (PEC-Eo) were isolated from the media conditioned by spleen cells from mice infected with Schistosoma japonicum by a combination of anion-exchange chromatography on DE52, affinity chromatography on Procion Red agarose, and high-performance liquid chromatography. The molecular weight of ECF-L directed against BM-Eo was 10,000 and that against PEC-Eo was 46,000 by SDS-PAGE analysis. After isolation, selectivity of the two distinct ECF-L was examined using BM-Eo, PEC-Eo and circulating Eo. ECF-L directed against BM-Eo could attract only BM-Eo, whereas that directed against PEC-Eo could attract not only PEC-Eo but also circulating Eo. Synthetic ECF-A was chemotactic against both BM- and circulating-Eo but not against PEC-Eo. When BM-Eo were cultured with ECF-L selective to PEC-Eo, they became reactive to ECF-L selective to PEC-Eo, whereas ECF-L selective to BM-Eo did not have such effect. These results suggest that ECF-L selective to PEC-Eo is not simply a chemoattractant but also is important in eosinophil differentiation.

  16. Genomic linkage map of the human blood fluke Schistosoma mansoni

    PubMed Central

    Criscione, Charles D; Valentim, Claudia LL; Hirai, Hirohisa; LoVerde, Philip T; Anderson, Timothy JC

    2009-01-01

    Background Schistosoma mansoni is a blood fluke that infects approximately 90 million people. The complete life cycle of this parasite can be maintained in the laboratory, making this one of the few experimentally tractable human helminth infections, and a rich literature reveals heritable variation in important biomedical traits such as virulence, host-specificity, transmission and drug resistance. However, there is a current lack of tools needed to study S. mansoni's molecular, quantitative, and population genetics. Our goal was to construct a genetic linkage map for S. mansoni, and thus provide a new resource that will help stimulate research on this neglected pathogen. Results We genotyped grandparents, parents and 88 progeny to construct a 5.6 cM linkage map containing 243 microsatellites positioned on 203 of the largest scaffolds in the genome sequence. The map allows 70% of the estimated 300 Mb genome to be ordered on chromosomes, and highlights where scaffolds have been incorrectly assembled. The markers fall into eight main linkage groups, consistent with seven pairs of autosomes and one pair of sex chromosomes, and we were able to anchor linkage groups to chromosomes using fluorescent in situ hybridization. The genome measures 1,228.6 cM. Marker segregation reveals higher female recombination, confirms ZW inheritance patterns, and identifies recombination hotspots and regions of segregation distortion. Conclusions The genetic linkage map presented here is the first for S. mansoni and the first for a species in the phylum Platyhelminthes. The map provides the critical tool necessary for quantitative genetic analysis, aids genome assembly, and furnishes a framework for comparative flatworm genomics and field-based molecular epidemiological studies. PMID:19566921

  17. Characterization of a gene family encoding SEA (sea-urchin sperm protein, enterokinase and agrin)-domain proteins with lectin-like and heme-binding properties from Schistosoma japonicum.

    PubMed

    Mbanefo, Evaristus Chibunna; Kikuchi, Mihoko; Huy, Nguyen Tien; Shuaibu, Mohammed Nasir; Cherif, Mahamoud Sama; Yu, Chuanxin; Wakao, Masahiro; Suda, Yasuo; Hirayama, Kenji

    2014-01-01

    We previously identified a novel gene family dispersed in the genome of Schistosoma japonicum by retrotransposon-mediated gene duplication mechanism. Although many transcripts were identified, no homolog was readily identifiable from sequence information. Here, we utilized structural homology modeling and biochemical methods to identify remote homologs, and characterized the gene products as SEA (sea-urchin sperm protein, enterokinase and agrin)-domain containing proteins. A common extracellular domain in this family was structurally similar to SEA-domain. SEA-domain is primarily a structural domain, known to assist or regulate binding to glycans. Recombinant proteins from three members of this gene family specifically interacted with glycosaminoglycans with high affinity, with potential implication in ligand acquisition and immune evasion. Similar approach was used to identify a heme-binding site on the SEA-domain. The heme-binding mode showed heme molecule inserted into a hydrophobic pocket, with heme iron putatively coordinated to two histidine axial ligands. Heme-binding properties were confirmed using biochemical assays and UV-visible absorption spectroscopy, which showed high affinity heme-binding (K D = 1.605×10(-6) M) and cognate spectroscopic attributes of hexa-coordinated heme iron. The native proteins were oligomers, antigenic, and are localized on adult worm teguments and gastrodermis; major host-parasite interfaces and site for heme detoxification and acquisition. The results suggest potential role, at least in the nucleation step of heme crystallization (hemozoin formation), and as receptors for heme uptake. Survival strategies exploited by parasites, including heme homeostasis mechanism in hemoparasites, are paramount for successful parasitism. Thus, assessing prospects for application in disease intervention is warranted.

  18. Functional Impairment of Human Myeloid Dendritic Cells during Schistosoma haematobium Infection

    PubMed Central

    Everts, Bart; Adegnika, Ayola A.; Kruize, Yvonne C. M.; Smits, Hermelijn H.; Kremsner, Peter G.; Yazdanbakhsh, Maria

    2010-01-01

    Chronic Schistosoma infection is often characterized by a state of T cell hyporesponsiveness of the host. Suppression of dendritic cell (DC) function could be one of the mechanisms underlying this phenomenon, since Schistosoma antigens are potent modulators of dendritic cell function in vitro. Yet, it remains to be established whether DC function is modulated during chronic human Schistosoma infection in vivo. To address this question, the effect of Schistosoma haematobium infection on the function of human blood DC was evaluated. We found that plasmacytoid (pDC) and myeloid DC (mDC) from infected subjects were present at lower frequencies in peripheral blood and that mDC displayed lower expression levels of HLA-DR compared to those from uninfected individuals. Furthermore, mDC from infected subjects, but not pDC, were found to have a reduced capacity to respond to TLR ligands, as determined by MAPK signaling, cytokine production and expression of maturation markers. Moreover, the T cell activating capacity of TLR-matured mDC from infected subjects was lower, likely as a result of reduced HLA-DR expression. Collectively these data show that S. haematobium infection is associated with functional impairment of human DC function in vivo and provide new insights into the underlying mechanisms of T cell hyporesponsiveness during chronic schistosomiasis. PMID:20422029

  19. Cost-effectiveness analysis of the impacts on infection and morbidity attributable to three chemotherapy schemes against Schistosoma japonicum in hyperendemic areas of the Dongting Lake region, China.

    PubMed

    Yu, Dongbao; Sarol, Jesus N; Hutton, Guy; Tan, Dunli; Tanner, Marcel

    2002-09-01

    A study was carried out in 8 villages endemic with S. japonicum in Hunan Province, China from 1998 to 2000 to evaluate the cost-effectiveness in preventing schistosome infection and related morbidity under three chemotherapy schemes: (1) 'clue' chemotherapy, consisting of treatment to those with contact with infected water and/or symptoms of infection; (2) 'mass' chemotherapy-treatment to all the villagers except those not able to take praziquantel; and (3) 'screen' chemotherapy-treatment prescribed to the stool egg positive cases after Kato-Katz examination. An itemized cost menu was used to estimate the cost incurred to each scheme, from the perspective of the health care provider. The numbers of cases prevented by chemotherapy schemes were estimated through standardized attributable fractions of the outcomes to absence of chemotherapy before intervention. The cost-effectiveness ratios were calculated using weighted ranks of unit costs of the four outcome measurements: the costs per case with infection, liver and spleen abnormality (as determined by ultrasonography) prevented and 1% reduction in intensity of infection (as estimated by egg per gram feces, EPG) after the two years of intervention. Sensitivity of total cost to changes in the costs of personnel, praziquantel and other key factors were analyzed. It is demonstrated that all the three schemes had a significant impacts on the prevalence and intensity of infection, but the overall effects on liver and spleen morbidity of the residents varied between schemes. Mass chemotherapy achieved the best cost-effectiveness ratio, with unit costs of preventing cases of infection, liver and spleen abnormality and 1% reduction of EPG being RMB yuan 161.2, 99.8, 219.3 and 176.3, respectively. However, clue and screen chemotherapy schemes did not show significant prevention of liver damages in the villagers. The unit costs per case prevented for the outcomes were RMB yuan 140.2, 602.7 and 169.3, respectively for clue

  20. The complete mitochondrial genomes of Schistosoma haematobium and Schistosoma spindale and the evolutionary history of mitochondrial genome changes among parasitic flatworms.

    PubMed

    Littlewood, D Timothy J; Lockyer, Anne E; Webster, Bonnie L; Johnston, David A; Le, Thanh Hoa

    2006-05-01

    Complete mitochondrial genome sequences for the schistosomes Schistosoma haematobium and Schistosoma. spindale have been characterized. S. haematobium is the causative agent of urinary schistosomiasis in humans and S. spindale uses ruminants as its definitive host; both are transmitted by freshwater snail intermediate hosts. Results confirm a major gene order rearrangement among schistosomes in all traditional Schistosoma species groups other than Schistosoma japonicum; i.e., species groups S. mansoni, S. haematobium, and S. indicum. These data lend support to the 'out of Asia' (East and Southeast Asia) hypothesis for Schistosoma. The gene order change involves translocation of atp6-nad2-trnA and a rearrangement of nad3-nad1 relative to other parasitic flatworm mt genomes so far sequenced. Gene order and tRNA secondary structure changes (loss and acquisition of the DHU and/or TPsiC arms of trnC, trnF, and trnR) between mitochondrial genomes of these and other (digenean and cestode) flatworms were inferred by character mapping onto a phylogeny estimated from nuclear small subunit rRNA gene sequences of these same species, in order to find additional rare genomic changes suitable as synapomorphies. Denser and wider taxon sampling of mt genomes across the Platyhelminthes will validate these putative characters.

  1. Non-human vertebrate hosts of Schistosoma haematobium and Schistosoma mansoni

    PubMed Central

    Martins, A. Vianna

    1958-01-01

    The author reviews the results of experimental infections of various species of mammals, other than man, with S. haematobium and S. mansoni, and discusses investigations in Africa and Brazil into the possibility of the natural infection of non-human vertebrates with these two parasites. Only a few species, besides monkeys, could be easily infected with S. haematobium in the laboratory, while—outside man—natural infection with this parasite appears to be practically non-existent. On the other hand, many animals are good experimental hosts for S. mansoni, and at least 21 species of mammals have been found infected with this parasite in Africa and America. It is thus possible to state, provisionally, that man is the only reservoir of S. haematobium, but the question still remains open where S. mansoni is concerned. Further research is suggested in order to assess the importance of non-human reservoirs in the epidemiology of bilharziasis. PMID:13573118

  2. Whole genome resequencing of the human parasite Schistosoma mansoni reveals population history and effects of selection.

    PubMed

    Crellen, Thomas; Allan, Fiona; David, Sophia; Durrant, Caroline; Huckvale, Thomas; Holroyd, Nancy; Emery, Aidan M; Rollinson, David; Aanensen, David M; Berriman, Matthew; Webster, Joanne P; Cotton, James A

    2016-02-16

    Schistosoma mansoni is a parasitic fluke that infects millions of people in the developing world. This study presents the first application of population genomics to S. mansoni based on high-coverage resequencing data from 10 global isolates and an isolate of the closely-related Schistosoma rodhaini, which infects rodents. Using population genetic tests, we document genes under directional and balancing selection in S. mansoni that may facilitate adaptation to the human host. Coalescence modeling reveals the speciation of S. mansoni and S. rodhaini as 107.5-147.6KYA, a period which overlaps with the earliest archaeological evidence for fishing in Africa. Our results indicate that S. mansoni originated in East Africa and experienced a decline in effective population size 20-90KYA, before dispersing across the continent during the Holocene. In addition, we find strong evidence that S. mansoni migrated to the New World with the 16-19th Century Atlantic Slave Trade.

  3. Whole genome resequencing of the human parasite Schistosoma mansoni reveals population history and effects of selection

    PubMed Central

    Crellen, Thomas; Allan, Fiona; David, Sophia; Durrant, Caroline; Huckvale, Thomas; Holroyd, Nancy; Emery, Aidan M.; Rollinson, David; Aanensen, David M.; Berriman, Matthew; Webster, Joanne P.; Cotton, James A.

    2016-01-01

    Schistosoma mansoni is a parasitic fluke that infects millions of people in the developing world. This study presents the first application of population genomics to S. mansoni based on high-coverage resequencing data from 10 global isolates and an isolate of the closely-related Schistosoma rodhaini, which infects rodents. Using population genetic tests, we document genes under directional and balancing selection in S. mansoni that may facilitate adaptation to the human host. Coalescence modeling reveals the speciation of S. mansoni and S. rodhaini as 107.5–147.6KYA, a period which overlaps with the earliest archaeological evidence for fishing in Africa. Our results indicate that S. mansoni originated in East Africa and experienced a decline in effective population size 20–90KYA, before dispersing across the continent during the Holocene. In addition, we find strong evidence that S. mansoni migrated to the New World with the 16–19th Century Atlantic Slave Trade. PMID:26879532

  4. SmCL3, a Gastrodermal Cysteine Protease of the Human Blood Fluke Schistosoma mansoni

    PubMed Central

    Dvořák, Jan; Mashiyama, Susan T.; Sajid, Mohammed; Braschi, Simon; Delcroix, Melaine; Schneider, Eric L.; McKerrow, Wilson H.; Bahgat, Mahmoud; Hansell, Elizabeth; Babbitt, Patricia C.; Craik, Charles S.; McKerrow, James H.; Caffrey, Conor R.

    2009-01-01

    Background Blood flukes of the genus Schistosoma are platyhelminth parasites that infect 200 million people worldwide. Digestion of nutrients from the host bloodstream is essential for parasite development and reproduction. A network of proteolytic enzymes (proteases) facilitates hydrolysis of host hemoglobin and serum proteins. Methodology/Principal Findings We identified a new cathepsin L termed SmCL3 using PCR strategies based on S. mansoni EST sequence data. An ortholog is present in Schistosoma japonicum. SmCL3 was heterologously expressed as an active enzyme in the yeast, Pichia pastoris. Recombinant SmCL3 has a broad pH activity range against peptidyl substrates and is inhibited by Clan CA protease inhibitors. Consistent with a function in degrading host proteins, SmCL3 hydrolyzes serum albumin and hemoglobin, is localized to the adult gastrodermis, and is expressed mainly in those life stages infecting the mammalian host. The predominant form of SmCL3 in the parasite exists as a zymogen, which is unusual for proteases. This zymogen includes an unusually long prodomain with alpha helical secondary structure motifs. The striking specificity of SmCL3 for amino acids with large aromatic side chains (Trp and Tyr) at the P2 substrate position, as determined with positional scanning-synthetic combinatorial library, is consistent with a molecular model that shows a large and deep S2 pocket. A sequence similarity network (SSN) view clusters SmCL3 and other cathepsins L in accordance with previous large-scale phylogenetic analyses that identify six super kingdoms. Conclusions/Significance SmCL3 is a gut-associated cathepsin L that may contribute to the network of proteases involved in degrading host blood proteins as nutrients. Furthermore, this enzyme exhibits some unusual sequence and biophysical features that may result in additional functions. The visualization of network inter-relationships among cathepsins L suggests that these enzymes are suitable

  5. Genetic Diversity of Schistosoma haematobium Eggs Isolated from Human Urine in Sudan.

    PubMed

    Quan, Juan-Hua; Choi, In-Wook; Ismail, Hassan Ahmed Hassan Ahmed; Mohamed, Abdoelohab Saed; Jeong, Hoo-Gn; Lee, Jin-Su; Hong, Sung-Tae; Yong, Tai-Soon; Cha, Guang-Ho; Lee, Young-Ha

    2015-06-01

    The genetic diversity of Schistosoma haematobium remains largely unstudied in comparison to that of Schistosoma mansoni. To characterize the extent of genetic diversity in S. haematobium among its definitive host (humans), we collected S. haematobium eggs from the urine of 73 infected schoolchildren at 5 primary schools in White Nile State, Sudan, and then performed a randomly amplified polymorphic DNA marker ITS2 by PCR-RFLP analysis. Among 73 S. haematobium egg-positive cases, 13 were selected based on the presence of the S. haematobium satellite markers A4 and B2 in their genomic DNA, and used for RFLP analysis. The 13 samples were subjected to an RFLP analysis of the S. haematobium ITS2 region; however, there was no variation in size among the fragments. Compared to the ITS2 sequences obtained for S. haematobium from Kenya, the nucleotide sequences of the ITS2 regions of S. haematobium from 4 areas in Sudan were consistent with those from Kenya (> 99%). In this study, we demonstrate for the first time that most of the S. haematobium population in Sudan consists of a pan-African S. haematobium genotype; however, we also report the discovery of Kenyan strain inflow into White Nile, Sudan.

  6. Genetic Diversity of Schistosoma haematobium Eggs Isolated from Human Urine in Sudan

    PubMed Central

    Quan, Juan-Hua; Choi, In-Wook; Ismail, Hassan Ahmed Hassan Ahmed; Mohamed, Abdoelohab Saed; Jeong, Hoo-Gn; Lee, Jin-Su; Hong, Sung-Tae; Yong, Tai-Soon; Cha, Guang-Ho; Lee, Young-Ha

    2015-01-01

    The genetic diversity of Schistosoma haematobium remains largely unstudied in comparison to that of Schistosoma mansoni. To characterize the extent of genetic diversity in S. haematobium among its definitive host (humans), we collected S. haematobium eggs from the urine of 73 infected schoolchildren at 5 primary schools in White Nile State, Sudan, and then performed a randomly amplified polymorphic DNA marker ITS2 by PCR-RFLP analysis. Among 73 S. haematobium egg-positive cases, 13 were selected based on the presence of the S. haematobium satellite markers A4 and B2 in their genomic DNA, and used for RFLP analysis. The 13 samples were subjected to an RFLP analysis of the S. haematobium ITS2 region; however, there was no variation in size among the fragments. Compared to the ITS2 sequences obtained for S. haematobium from Kenya, the nucleotide sequences of the ITS2 regions of S. haematobium from 4 areas in Sudan were consistent with those from Kenya (> 99%). In this study, we demonstrate for the first time that most of the S. haematobium population in Sudan consists of a pan-African S. haematobium genotype; however, we also report the discovery of Kenyan strain inflow into White Nile, Sudan. PMID:26174820

  7. Isoforms of Hsp70-binding human LDL in adult Schistosoma mansoni worms.

    PubMed

    Pereira, Adriana S A; Cavalcanti, Marília G S; Zingali, Russolina B; Lima-Filho, José L; Chaves, Maria E C

    2015-03-01

    Schistosoma mansoni is one of the most common parasites infecting humans. They are well adapted to the host, and this parasite's longevity is a consequence of effective escape from the host immune system. In the blood circulation, lipoproteins not only help to conceal the worm from attack by host antibodies but also act as a source of lipids for S. mansoni. Previous SEM studies showed that the low-density lipoprotein (LDL) particles present on the surface of adult S. mansoni worms decreased in size when the incubation time increased. In this study, immunocytochemical and proteomic analyses were used to locate and identify S. mansoni binding proteins to human plasma LDL. Ultrathin sections of adult worms were cut transversely from the anterior, medial and posterior regions of the parasite. Immunocytochemical experiments revealed particles of gold in the tegument, muscle region and spine in male worms and around vitelline cells in females. Immunoblotting and 2D-electrophoresis using incubations with human serum, anti-LDL antibodies and anti-chicken IgG peroxidase conjugate were performed to identify LDL-binding proteins in S. mansoni. Analysis of the binding proteins using LC-MS identified two isoforms of the Hsp70 chaperone in S. mansoni. Hsp70 is involved in the interaction with apoB in the cytoplasm and its transport to the endoplasmic reticulum. However, further studies are needed to clarify the functional role of Hsp70 in S. mansoni, mainly related to the interaction with human LDL.

  8. Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques.

    PubMed

    Pardo, J; Carranza, C; Turrientes, M C; Pérez Arellano, J L; López Vélez, R; Ramajo, V; Muro, A

    2004-11-01

    Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.

  9. Utility of Schistosoma bovis Adult Worm Antigens for Diagnosis of Human Schistosomiasis by Enzyme-Linked Immunosorbent Assay and Electroimmunotransfer Blot Techniques

    PubMed Central

    Pardo, J.; Carranza, C.; Turrientes, M. C.; Arellano, J. L. Pérez; Vélez, R. López; Ramajo, V.; Muro, A.

    2004-01-01

    Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive. PMID:15539523

  10. Immunoaffinity fractionation of Schistosoma mansoni worm antigens using human antibodies and its application for serodiagnosis.

    PubMed Central

    Boctor, F N; Shaheen, H I

    1986-01-01

    A crude Schistosoma mansoni soluble worm antigen preparation (SWAP) was fractionated using an immunoaffinity column consisting of specific human anti-SWAP antibodies obtained from chronic S. mansoni-infected human sera and bound to CNBr-activated Sepharose 4B. The chromatographic separation resulted in three fractions: the unbound material (FW), and the eluted antigens with glycine-HCl (F1) and glycine-HCl-NaCl (F2). Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the purified antigens F1 and F2 consisted of several bands when stained with Coomassie blue and silver stain, with molecular weights between 20 X 10(3) and 200 X 10(3). The F1 and F2 fractions in addition to FW and SWAP were used in an enzyme-linked immunosorbent assay (ELISA) to measure antibody levels in sera from schistosomiasis patients. Each individual serum assessed with the purified F2 antigen gave 100% positivity and three to four times higher optical density in comparison to SWAP with only 88% positivity. No detectable cross-reactive antibodies against F2 were found when a limited number of sera from filariasis, fascioliasis and trichinellosis patients were screened. Furthermore, F2 was also used and found to be more sensitive generally in detecting anti-adult worm antibodies than SWAP in recently schistosomiasis-infected persons. Thus, F2 appears to be a highly sensitive and specific reagent for the serodiagnosis of schistosomiasis infection. Images Figure 3 Figure 7 PMID:3082749

  11. Association of Schistosoma haematobium and human papillomavirus in cervical cancer: a case report.

    PubMed

    Savardekar, Lalita S; Balaiah, Donta; Mali, Bapurao N

    2010-01-01

    The association between Schistosoma haematobium and cervical cancer has been reported for a long time. However, recently human papillomavirus, a cofactor in the genesis of cervical cancer, has been confirmed. A case of squamous intraepithelial lesion after S haematobium infection is presented, and the relation between schistosomiasis, human papillomavirus and squamous intraepithelial lesion, with long-term follow-up by Papanicolaou smear, is discussed. A 33-year-old, normal, healthy woman with a history of Copper intrauterine device (IUD) use for 3.9 years presented for her annual contraceptive follow-up. Her Pap smear revealed inflammation with a S haematobium egg. She was followed up with Pap smears for 4 years. Retrospective contraceptive history revealed use ofa copper IUD on 5 occasions with a total duration of 13 years and 1 month. Similarly, annual follow-up of Pap smears for the past 13 years showed mild inflammation with bacterial vaginitis and monilial infection. Subsequent smears showed an Actinomyces-like organism and then human papillomavirus infection with atypical squamous cells of undetermined significance followed by human papillomavirus-associated low/high grade squamous intraepithelial lesion. Caution is required while screening routine Pap smears. Apart from nuclear abnormalities, one can observe unusual findings. Long-term followup by Pap smear following detection of S haematobium revealed that in the absence of human papillomavirus, S haematobium alone is not the causative agent for the abnormal proliferation of squamous epithelium of the cervix. Genital Schistosomia acts as a cofactor by traumatizing the genital epithelium or immune suppression to favor human papillomavirus infection.

  12. HIV-1 Integrates Widely throughout the Genome of the Human Blood Fluke Schistosoma mansoni

    PubMed Central

    Mann, Victoria H.; Dubrovsky, Larisa; Yan, Hong-bin; Huckvale, Thomas; Protasio, Anna V.; Pushkarsky, Tatiana; Iordanskiy, Sergey; Bukrinsky, Michael I.

    2016-01-01

    Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the RNA genome reverse transcribed. Anchored PCR analysis, sequencing HIV-1-specific anchored Illumina libraries and Whole Genome Sequencing (WGS) of schistosomes confirmed chromosomal integration; >8,000 integrations were mapped, distributed throughout the eight pairs of chromosomes including the sex chromosomes. The rate of integrations in the genome exceeded five per 1,000 kb and HIV-1 integrated into protein-encoding loci and elsewhere with integration bias dissimilar to that of human T cells. We estimated ~ 2,100 integrations per schistosomulum based on WGS, i.e. about two or three events per cell, comparable to integration rates in human cells. Accomplishment in schistosomes of post-entry processes essential for HIV-1replication, including integrase-catalyzed integration, was remarkable given the phylogenetic distance between schistosomes and primates, the natural hosts of the genus Lentivirus. These enigmatic findings revealed that HIV-1 was active within cells of S. mansoni, and provided the first demonstration that HIV-1 can integrate into the genome of an invertebrate. PMID:27764257

  13. HIV-1 Integrates Widely throughout the Genome of the Human Blood Fluke Schistosoma mansoni.

    PubMed

    Suttiprapa, Sutas; Rinaldi, Gabriel; Tsai, Isheng J; Mann, Victoria H; Dubrovsky, Larisa; Yan, Hong-Bin; Holroyd, Nancy; Huckvale, Thomas; Durrant, Caroline; Protasio, Anna V; Pushkarsky, Tatiana; Iordanskiy, Sergey; Berriman, Matthew; Bukrinsky, Michael I; Brindley, Paul J

    2016-10-01

    Schistosomiasis is the most important helminthic disease of humanity in terms of morbidity and mortality. Facile manipulation of schistosomes using lentiviruses would enable advances in functional genomics in these and related neglected tropical diseases pathogens including tapeworms, and including their non-dividing cells. Such approaches have hitherto been unavailable. Blood stream forms of the human blood fluke, Schistosoma mansoni, the causative agent of the hepatointestinal schistosomiasis, were infected with the human HIV-1 isolate NL4-3 pseudotyped with vesicular stomatitis virus glycoprotein. The appearance of strong stop and positive strand cDNAs indicated that virions fused to schistosome cells, the nucleocapsid internalized and the RNA genome reverse transcribed. Anchored PCR analysis, sequencing HIV-1-specific anchored Illumina libraries and Whole Genome Sequencing (WGS) of schistosomes confirmed chromosomal integration; >8,000 integrations were mapped, distributed throughout the eight pairs of chromosomes including the sex chromosomes. The rate of integrations in the genome exceeded five per 1,000 kb and HIV-1 integrated into protein-encoding loci and elsewhere with integration bias dissimilar to that of human T cells. We estimated ~ 2,100 integrations per schistosomulum based on WGS, i.e. about two or three events per cell, comparable to integration rates in human cells. Accomplishment in schistosomes of post-entry processes essential for HIV-1replication, including integrase-catalyzed integration, was remarkable given the phylogenetic distance between schistosomes and primates, the natural hosts of the genus Lentivirus. These enigmatic findings revealed that HIV-1 was active within cells of S. mansoni, and provided the first demonstration that HIV-1 can integrate into the genome of an invertebrate.

  14. A functionally atypical amidating enzyme from the human parasite Schistosoma mansoni.

    PubMed

    Mair, Gunnar R; Niciu, Mark J; Stewart, Michael T; Brennan, Gerry; Omar, Hanan; Halton, David W; Mains, Richard; Eipper, Betty A; Maule, Aaron G; Day, Tim A

    2004-01-01

    Many neuropeptide transmitters require the presence of a carboxy-terminal alpha-amide group for biological activity. Amidation requires conversion of a glycine-extended peptide intermediate into a C-terminally amidated product. This post-translational modification depends on the sequential action of two enzymes (peptidylglycine alpha-hydroxylating monooxygenase or PHM, and peptidyl-alpha-hydroxyglycine alpha-amidating lyase or PAL) that in most eukaryotes are expressed as separate domains of a single protein (peptidylglycine alpha-amidating monooxygenase or PAM). We identified a cDNA encoding PHM in the human parasite Schistosoma mansoni. Transient expression of schistosome PHM (smPHM) revealed functional properties that are different from other PHM proteins; smPHM displays a lower pH-optimum and, when expressed in mammalian cells, is heavily N-glycosylated. In adult worms, PHM is found in the trans-Golgi network and secretory vesicles of both central and peripheral nerves. The widespread occurrence of PHM in the nervous system confirms the important role of amidated neuropeptides in these parasitic flatworms. The differences between schistosome and mammalian PHM suggest that it could be a target for new chemotherapeutics.

  15. Schistosoma mansoni Sambon, 1907: morphometric differences between adult worms from sympatric rodent and human isolates.

    PubMed

    Neves, R H; Pereira, M J; de Oliveira, R M; Gomes, D C; Machado-Silva, J R

    1998-01-01

    A computer software for image analysis (IMAGE PRO PLUS, MEDIA CYBERNETICS) was utilized in male and females adult worms, aiming the morphological characterization of Schistosoma mansoni samples isolated from a slyvatic rodent, Nectomys squamipes, and humans in Sumidouro, Rio de Janeiro, Brazil and recovered from Mus musculus C3H/He. The following characters for males's testicular lobes were analyzed: number, area, density, larger and smaller diameter, longer and shorter axis and perimeter and extension; for females: area, longer and shorter axis, larger and smaller diameter and perimeter of the eggs and spine; oral and ventral suckers area and distance between them in both sex were determined. By the analysis of variance (one way ANOVA) significant differences (p < 0.05) were observed in all studied characters, except for the density of testicular lobes. Significant differences (p < 0.05) were detected for all characters in the female worms. Data ratify that sympatric isolates present phenotypic differences and the adult female characters are useful for the proper identification of S. mansoni isolates.

  16. Association between Schistosoma haematobium Exposure and Human Immunodeficiency Virus Infection among Females in Mozambique

    PubMed Central

    Brodish, Paul Henry; Singh, Kavita

    2016-01-01

    Recent evidence suggests an association between human immunodeficiency virus (HIV) and female genital schistosomiasis (FGS) in sub-Saharan Africa, especially in Mozambique, South Africa, Tanzania, and Zimbabwe. Women with FGS have increased numbers of HIV target cells and cell receptors in genital and blood compartments, potentially increasing the risk of HIV transmission per sexual exposure, and the association may explain the high female:male ratio of HIV prevalence unique to sub-Saharan Africa. We investigate this association in Mozambique by linking two georeferenced, high-quality secondary data sources on HIV prevalence and Schistosoma haematobium: the AIDS Indicator Survey, and the Global Neglected Tropical Diseases (GNTD) open-source database, respectively. We construct a schistosomiasis exposure covariate indicating women reporting “unimproved” daily drinking water sources and living no more than 2–5 km from high-endemic global positioning system (GPS) coordinates in the GNTD. In logistic regression analyses predicting HIV-positive status, we show that exposure increases the odds of HIV-positive status by three times, controlling for demographic and sexual risk factors. PMID:26976893

  17. Human TNF-α induces differential protein phosphorylation in Schistosoma mansoni adult male worms.

    PubMed

    Oliveira, Katia C; Carvalho, Mariana L P; Bonatto, José Matheus C; Schechtman, Debora; Verjovski-Almeida, Sergio

    2016-02-01

    Schistosoma mansoni and its vertebrate host have a complex and intimate connection in which several molecular stimuli are exchanged and affect both organisms. Human tumor necrosis factor alpha (hTNF-α), a pro-inflammatory cytokine, is known to induce large-scale gene expression changes in the parasite and to affect several parasite biological processes such as metabolism, egg laying, and worm development. Until now, the molecular mechanisms for TNF-α activity in worms are not completely understood. Here, we aimed at exploring the effect of hTNF-α on S. mansoni protein phosphorylation by 2D gel electrophoresis followed by a quantitative analysis of phosphoprotein staining and protein identification by mass spectrometry. We analyzed three biological replicates of adult male worms exposed to hTNF-α and successfully identified 32 protein spots with a statistically significant increase in phosphorylation upon in vitro exposure to hTNF-α. Among the differentially phosphorylated proteins, we found proteins involved in metabolism, such as glycolysis, galactose metabolism, urea cycle, and aldehyde metabolism, as well as proteins related to muscle contraction and to cytoskeleton remodeling. The most differentially phosphorylated protein (30-fold increase in phosphorylation) was 14-3-3, whose function is known to be modulated by phosphorylation, belonging to a signal transduction protein family that regulates a variety of processes in all eukaryotic cells. Further, 75% of the identified proteins are known in mammals to be related to TNF-α signaling, thus suggesting that TNF-α response may be conserved in the parasite. We propose that this work opens new perspectives to be explored in the study of the molecular crosstalk between host and pathogen.

  18. Inbreeding within human Schistosoma mansoni: do host-specific factors shape the genetic composition of parasite populations?

    PubMed

    Van den Broeck, F; Meurs, L; Raeymaekers, J A M; Boon, N; Dieye, T N; Volckaert, F A M; Polman, K; Huyse, T

    2014-07-01

    The size, structure and distribution of host populations are key determinants of the genetic composition of parasite populations. Despite the evolutionary and epidemiological merits, there has been little consideration of how host heterogeneities affect the evolutionary trajectories of parasite populations. We assessed the genetic composition of natural populations of the parasite Schistosoma mansoni in northern Senegal. A total of 1346 parasites were collected from 14 snail and 57 human hosts within three villages and individually genotyped using nine microsatellite markers. Human host demographic parameters (age, gender and village of residence) and co-infection with Schistosoma haematobium were documented, and S. mansoni infection intensities were quantified. F-statistics and clustering analyses revealed a random distribution (panmixia) of parasite genetic variation among villages and hosts, confirming the concept of human hosts as 'genetic mixing bowls' for schistosomes. Host gender and village of residence did not show any association with parasite genetics. Host age, however, was significantly correlated with parasite inbreeding and heterozygosity, with children being more infected by related parasites than adults. The patterns may be explained by (1) genotype-dependent 'concomitant immunity' that leads to selective recruitment of genetically unrelated worms with host age, and/or (2) the 'genetic mixing bowl' hypothesis, where older hosts have been exposed to a wider variety of parasite strains than children. The present study suggests that host-specific factors may shape the genetic composition of schistosome populations, revealing important insights into host-parasite interactions within a natural system.

  19. Evaluation of three extraction methods for molecular detection of Schistosoma mansoni infection in human urine and serum samples.

    PubMed

    Sarhan, Rania M; Kamel, Hanan H; Saad, Ghada A; Ahmed, Ossama A

    2015-09-01

    The diagnostic techniques based on polymerase chain reaction (PCR) for the detection of Schistosoma spp. DNA in stool, serum, plasma and urine has shown high sensitivity and specificity solving the problems for the low worm burdens and low transmission rates facing the routine microscopic diagnosis. Since PCR assays require efficient unbiased procedures of extraction and purification of nucleic acids. This study compared the efficiencies of simple, manual and feasible DNA extraction methods; a salting out and resin method, phenol/chloroform method to a commercial extraction kit through PCR analysis of human urine and serum samples spiked with known amounts of adult Schistosoma mansoni DNA confirmed by the application on real samples from patients. In artificially spiked urine gradient, the best mean diagnostic performance was that of salting out and resin then phenol/chloroform and last for the commercial kit. All three methods gave positive results in all tested urine samples which insures comparable high efficiency for DNA detection. In artificially spiked serum gradient, the highest mean diagnostic performance was obtained by the kit then salting out and resin and last by phenol chloroform. In patients' urine samples the phenol/chloroform method showed the highest mean diagnostic performance followed by the resin and then the kit. Using patients' serum samples the resin method showed equal mean diagnostic performance with the phenol/chloroform method which was higher compared to the kit. As regards sensitivity from urine samples the resin and phenol/chloroform showed equal results using artificial gradients and patients' samples. In serum samples the resin and phenol/chloroform showed equal results using artificial gradients while the resin showed better results in patients' samples. It is recommended to extract DNA from urine samples and to use the salting out and resin as a manual DNA extraction method from patients' samples for the molecular diagnosis of

  20. Epidemiology and interactions of Human Immunodeficiency Virus – 1 and Schistosoma mansoni in sub-Saharan Africa

    PubMed Central

    2013-01-01

    Human Immunodeficiency Virus-1/AIDS and Schistosoma mansoni are widespread in sub-Saharan Africa and co-infection occurs commonly. Since the early 1990s, it has been suggested that the two infections may interact and potentiate the effects of each other within co-infected human hosts. Indeed, S. mansoni infection has been suggested to be a risk factor for HIV transmission and progression in Africa. If so, it would follow that mass deworming could have beneficial effects on HIV-1 transmission dynamics. The epidemiology of HIV in African countries is changing, shifting from urban to rural areas where the prevalence of Schistosoma mansoni is high and public health services are deficient. On the other side, the consequent pathogenesis of HIV-1/S. mansoni co-infection remains unknown. Here we give an account of the epidemiology of HIV-1 and S. mansoni, discuss co-infection and possible biological causal relationships between the two infections, and the potential impact of praziquantel treatment on HIV-1 viral loads, CD4+ counts and CD4+/CD8+ ratio. Our review of the available literature indicates that there is evidence to support the hypothesis that S. mansoni infections can influence the replication of the HIV-1, cell-to-cell transmission, as well as increase HIV progression as measured by reduced CD4+ T lymphocytes counts. If so, then deworming of HIV positive individuals living in endemic areas may impact on HIV-1 viral loads and CD4+ T lymphocyte counts. PMID:23849678

  1. Comparison of Schistosoma mansoni Soluble Cercarial Antigens and Soluble Egg Antigens for Serodiagnosing Schistosome Infections

    PubMed Central

    Doenhoff, Mike; Aitken, Cara; Bailey, Wendi; Ji, Minjun; Dawson, Emily; Gilis, Henk; Spence, Grant; Alexander, Claire; van Gool, Tom

    2012-01-01

    A Schistosoma mansoni cercarial antigen preparation (cercarial transformation fluid – SmCTF) was evaluated for detection of anti-schistosome antibodies in human sera in 4 collaborating laboratories. The performance of SmCTF was compared with that of S. mansoni egg antigens (SmSEA) in an indirect enzyme-immunoassay (ELISA) antigen assay, the latter being used routinely in 3 of the 4 participating laboratories to diagnose S. mansoni and S. haematobium infections. In the fourth laboratory the performance of SmCTF was compared with that of S. japonicum egg antigens (SjSEA) in ELISA for detection of anti-S. japonicum antibodies. In all 4 laboratories the results given by SmCTF in ELISA were very similar to those given by the antigen preparation routinely used in the respective laboratory to detect anti-schistosome antibodies in human infection sera. In so far as the ELISA results from SmCTF are thus so little different from those given by schistosome egg antigens and also cheaper to produce, the former is a potentially useful new diagnostic aid for schistosomiasis. PMID:23029577

  2. Inbreeding within human Schistosoma mansoni: do host-specific factors shape the genetic composition of parasite populations?

    PubMed Central

    Van den Broeck, F; Meurs, L; Raeymaekers, J A M; Boon, N; Dieye, T N; Volckaert, F A M; Polman, K; Huyse, T

    2014-01-01

    The size, structure and distribution of host populations are key determinants of the genetic composition of parasite populations. Despite the evolutionary and epidemiological merits, there has been little consideration of how host heterogeneities affect the evolutionary trajectories of parasite populations. We assessed the genetic composition of natural populations of the parasite Schistosoma mansoni in northern Senegal. A total of 1346 parasites were collected from 14 snail and 57 human hosts within three villages and individually genotyped using nine microsatellite markers. Human host demographic parameters (age, gender and village of residence) and co-infection with Schistosoma haematobium were documented, and S. mansoni infection intensities were quantified. F-statistics and clustering analyses revealed a random distribution (panmixia) of parasite genetic variation among villages and hosts, confirming the concept of human hosts as ‘genetic mixing bowls' for schistosomes. Host gender and village of residence did not show any association with parasite genetics. Host age, however, was significantly correlated with parasite inbreeding and heterozygosity, with children being more infected by related parasites than adults. The patterns may be explained by (1) genotype-dependent ‘concomitant immunity' that leads to selective recruitment of genetically unrelated worms with host age, and/or (2) the ‘genetic mixing bowl' hypothesis, where older hosts have been exposed to a wider variety of parasite strains than children. The present study suggests that host-specific factors may shape the genetic composition of schistosome populations, revealing important insights into host–parasite interactions within a natural system. PMID:24619176

  3. Evaluation of the treatment of human Schistosoma mansoni infection by the quantitative oogram technique*

    PubMed Central

    Cançado, J. Romeu; da Cunha, A. Sales; de Carvalho, D. Garcia; Cambraia, J. N. Santos

    1965-01-01

    Egg output is the only measure available for quantitative assessment of the activity of chemotherapeutic agents in Schistosoma mansoni infection. In the light of eight years' experience in the preparations of oograms, the authors suggest a simplified classification of S. mansoni eggs and certain improvements in the oogram technique by which quantitative data are obtained for comparison before and after treatment. Ten cases, taken from clinical trials on a variety of schistosomicidal compounds, are presented to illustrate the use of the quantitative oogram and the types of result obtained with active, partially active and inactive drugs. ImagesFIG. 3FIG. 2FIG. 1 PMID:5323117

  4. Introgressive Hybridization of Schistosoma haematobium Group Species in Senegal: Species Barrier Break Down between Ruminant and Human Schistosomes

    PubMed Central

    Webster, Bonnie L.; Diaw, Oumar T.; Seye, Mohmoudane M.; Webster, Joanne P.; Rollinson, David

    2013-01-01

    Background Schistosomes are dioecious parasitic flatworms, which live in the vasculature of their mammalian definitive hosts. They are the causative agent of schistosomiasis, a disease of considerable medical and veterinary importance in tropical and subtropical regions. Schistosomes undergo a sexual reproductive stage within their mammalian host enabling interactions between different species, which may result in hybridization if the species involved are phylogenetically close. In Senegal, three closely related species in the Schistosoma haematobium group are endemic: S. haematobium, which causes urogenital schistosomiasis in humans, and S. bovis and S. curassoni, which cause intestinal schistosomiasis in cows, sheep and goats. Methodology/Principal Findings Large-scale multi-loci molecular analysis of parasite samples collected from children and domestic livestock across Senegal revealed that interactions and hybridization were taking place between all three species. Evidence of hybridization between S. haematobium/S. curassoni and S. haematobium/S. bovis was commonly found in children from across Senegal, with 88% of the children surveyed in areas of suspected species overlap excreting hybrid miracidia. No S. haematobium worms or hybrids thereof were found in ruminants, although S. bovis and S. curassoni hybrid worms were found in cows. Complementary experimental mixed species infections in laboratory rodents confirmed that males and females of each species readily pair and produce viable hybrid offspring. Conclusions/Significance These data provide indisputable evidence for: the high occurrence of bidirectional hybridization between these Schistosoma species; the first conclusive evidence for the natural hybridisation between S. haematobium and S. curassoni; and demonstrate that the transmission of the different species and their hybrids appears focal. Hybridization between schistosomes has been known to influence the disease epidemiology and enhance phenotypic

  5. Mechanisms of Skin Penetration by Schistosoma Mansoni Cercariae.

    DTIC Science & Technology

    Schistosoma mansoni , Penetration, Skin(Anatomy), Cercariae, Enzymes, Chymotrypsin, Blood serum, Calcium, Zinc, Parasitic diseases, Control...Inhibitors, Gamma globulin, Infections, Surfaces, Schistosomiasis , Humans, In vitro analysis

  6. Repeats of LacdiNAc and fucosylated LacdiNAc on N-glycans of the human parasite Schistosoma mansoni.

    PubMed

    Wuhrer, Manfred; Koeleman, Carolien A M; Deelder, André M; Hokke, Cornelis H

    2006-01-01

    N-Glycans from glycoproteins of the worm stage of the human parasite Schistosoma mansoni were enzymatically released, fluorescently labelled and analysed using various mass spectrometric and chromatographic methods. A family of 28 mainly core-alpha1-6-fucosylated, diantennary N-glycans of composition Hex(3-4)HexNAc(6-12)Fuc(1-6) was found to carry dimers of N,N'-diacetyllactosediamine [LacdiNAc or LDN; GalNAc(beta1-4)GlcNAc(beta1-] with or without fucose alpha1-3-linked to the N-acetylglucosamine residues in the antennae {GalNAc(beta1-4)[+/-Fuc(alpha1-3)]GlcNAc(beta1-3)GalNAc(beta1-4)[+/-Fuc(alpha1-3)]GlcNAc(beta1-}. To date, oligomeric LDN and oligomeric fucosylated LDN (LDNF) have been found only on N-glycans from mammalian cells engineered to express Caenorhabditis elegansbeta4-GalNAc transferase and human alpha3-fucosyltransferase IX [Z. S. Kawar et al. (2005) J Biol Chem280, 12810-12819]. It now appears that LDN(F) repeats can also occur in a natural system such as the schistosome parasite. Like monomeric LDN and LDNF, the dimeric LDN(F) moieties found here are expected to be targets of humoral and cellular immune responses during schistosome infection.

  7. Functional and antigenic similarities between a 94-kD protein of Schistosoma mansoni (SCIP-1) and human CD59

    PubMed Central

    1994-01-01

    Schistosomiasis is a parasitic disease affecting approximately 200 million people, primarily in the third world. Schistosoma mansoni, one of the causative agents of this disease, parasitize the human mesenteric and portal blood systems while successfully evading host immune responses. During parasite penetration into the mammalian host and shortly afterwards, the larvae rapidly convert from being sensitive to being resistant to C-mediated killing. Treatment of the C-resistant parasitic forms with trypsin renders the parasite susceptible to C attack, thus indicating the presence of C inhibitory protein(s) on the parasite surface. We describe here an intrinsic schistosome C inhibitory protein (SCIP-1) that exhibits antigenic and functional similarities with the human C-inhibitor CD59. Like CD59, SCIP-1 is capable of inhibiting formation of the C membrane attack complex (MAC), probably by binding to C8 and C9 of the C terminal pathway. In addition, SCIP-1 is apparently also membrane-anchored via glycosyl phosphatidylinositol as it can be specifically released with phosphatidylinositol-specific phospholipase C. Soluble SCIP-1, partially purified from Nonidet P-40 extracts of schistosome tegument is capable of inhibiting hemolysis of sensitized sheep erythrocytes and of rabbit erythrocytes by human C. Anti-human CD59 antibodies block this activity of SCIP-1 and in addition, upon binding to intact parasites, render them vulnerable to killing by human and guinea pig C. SCIP-1 is located on the surface of C-resistant forms of the parasite, i.e., 24-h cultured mechanical schistosomula and in vivo-derived adult worms as revealed by immunofluorescence and immunogold electron microscopy studies. These results identify one of the mechanisms schistosomes use to escape immune attack. PMID:7513011

  8. A new PCR-based approach for the specific amplification of DNA from different Schistosoma species applicable to human urine samples.

    PubMed

    Sandoval, N; Siles-Lucas, M; Pérez-Arellano, J L; Carranza, C; Puente, S; López-Abán, J; Muro, A

    2006-11-01

    Currently available methods for the diagnosis of human schistosomiasis often lack enough sensitivity and specificity. Recently, several authors have developed more specific and sensitive diagnostic methods, mainly based on the polymerase chain reaction (PCR) technique. Nevertheless, these have been only applied for the diagnosis of 1 out of 4 Schistosoma species affecting man (S. mansoni). Additionally, application of specific PCR has been exclusively used for blood or faecal patients' samples. Here, we develop a new, high sensitive PCR approach that allows the genus- and species-specific amplification of the main 4 Schistosoma species causing disease in man plus S. bovis. We further successfully apply this technique for the detection of parasite DNA in easy-to-handle urine samples from patients with schistosomiasis. With these samples, we have found 94.4% sensitivity and 99.9% specificity when applying a genus-specific (Schistosoma spp.) primer pair, and 100% sensitivity and 98.9% specificity in a species-specific (S. mansoni) PCR.

  9. Pharmacological and autoradiographical characterization of serotonin transporter-like activity in sporocysts of the human blood fluke, Schistosoma mansoni.

    PubMed

    Boyle, J P; Hillyer, J F; Yoshino, T P

    2003-08-01

    The present study focuses on the role of the biogenic monoamine serotonin (5-hydroxytryptamine) in the biology of sporocyst stages of the human blood fluke, Schistosoma mansoni, and its importance during obligate development within its snail host Biomphalaria glabrata. Based on previous work demonstrating that snails infected with S. mansoni have reduced levels of 5-hydroxytryptamine, we hypothesized that sporocysts actively transport this molecule from the host milieu. Intact sporocysts isolated in vitro take up exogenous 5-hydroxytryptamine via a high-affinity mechanism (K(m)=1.4 micromol l(-1)), and this serotonin transporter-like activity is dependent upon extracellular Na(+) and Cl(-) and is highly sensitive to previously characterized serotonin transporter inhibitors. Autoradiography suggests that transported [(3)H]5-hydroxytryptamine localizes within the body of the sporocyst, and in many cases is found in apical gland cells. Moreover, serotonin transporter-like activity is absent in free-swimming miracidia, the infective stage for the snail host, and the increase in larval serotonin transporter-like activity after miracidium-to-sporocyst transformation is accompanied by a corresponding decrease in steady-state levels of transcripts for tryptophan hydroxylase, the rate-limiting enzyme in serotonin biosynthesis. Overall our data suggest that S. mansoni larvae express surface-exposed serotonin transporter-like molecules, and that the transition from free-living miracidium to parasitic mother sporocyst is characterized by an increased dependence upon exogenous 5-hydroxytryptamine.

  10. Characteristics of the Human Host Have Little Influence on Which Local Schistosoma mansoni Populations Are Acquired

    PubMed Central

    Barbosa, Lúcio M.; Silva, Luciano K.; Reis, Eliana A.; Azevedo, Theomira M.; Costa, Jackson M.; Blank, Walter A.; Reis, Mitermayer G.; Blanton, Ronald E.

    2013-01-01

    Background Brazil remains the country in the Americas with the highest prevalence of schistosomiasis. A combination of control efforts and development, however, has sharply reduced its intensity and distribution. The acquisition of specific schistosome populations may be dependent on host characteristics such as sex, age, geography, work, habits and culture. How these and other host characteristics align with parasite subpopulations may guide approaches to improve control. Methodology A cohort of more than 90% of the residents in two rural communities in Brazil participated in an epidemiologic survey of demographic, socio-economic and behavioral characteristics. The variables sex, age, intensity of infection, socio-economic index, % lifetime spent on site, previous infection, and trips outside the district were used to group parasites infecting individuals. Schistosoma mansoni infection status was determined by examination of stools submitted on 3 different days. The aggregate of eggs collected from the whole stool was used to determine degree of population differentiation from allele frequencies for 15 microsatellites. Conclusions/Significance Infection prevalence was 41% for these communities, and the epidemiologic characteristics were similar to many of the endemic areas of Brazil and the world. Parasite population structuring was observed between the two communities (Jost's D 0.046, CI95% 0.042–0.051), although separated by only 8 km and connected by a highway. No structuring was observed when infected individuals were stratified by host's biologic, demographic or epidemiologic characteristics. Those most heavily infected best reflected the communities' overall parasite diversity. The lack of differentiation within villages suggests that individuals are likely to get infected at the same sites or that the same parasite multilocus genotypes can be found at most sites. The geographic structuring between villages and the lack of structuring by age of the host

  11. Small gene family encoding an eggshell (chorion) protein of the human parasite Schistosoma mansoni

    SciTech Connect

    Bobek, L.A.; Rekosh, D.M.; Lo Verde, P.T.

    1988-08-01

    The authors isolated six independent genomic clones encoding schistosome chorion or eggshell proteins from a Schistosoma mansoni genomic library. A linkage map of five of the clones spanning 35 kilobase pairs (kbp) of the S. mansoni genome was constructed. The region contained two eggshell protein genes closely linked, separated by 7.5 kbp of intergenic DNA. The two genes of the cluster were arranged in the same orientation, that is, they were transcribed from the same strand. The sixth clone probably represents a third copy of the eggshell gene that is not contained within the 35-kbp region. The 5- end of the mRNA transcribed from these genes was defined by primer extension directly off the RNA. The ATCAT cap site sequence was homologous to a silkmoth chorion PuTCATT cap site sequence, where Pu indicates any purine. DNA sequence analysis showed that there were no introns in these genes. The DNA sequences of the three genes were very homologous to each other and to a cDNA clone, pSMf61-46, differing only in three or four nucleotices. A multiple TATA box was located at positions -23 to -31, and a CAAAT sequence was located at -52 upstream of the eggshell transcription unit. Comparison of sequences in regions further upstream with silkmoth and Drosophila sequences revealed very short elements that were shared. One such element, TCACGT, recently shown to be an essential cis-regulatory element for silkmoth chorion gene promoter function, was found at a similar position in all three organisms.

  12. Haem uptake is essential for egg production in the haematophagous blood fluke of humans, Schistosoma mansoni.

    PubMed

    Toh, Shu Qin; Gobert, Geoffrey N; Malagón Martínez, David; Jones, Malcolm K

    2015-09-01

    Schistosomes ingest host erythrocytes, liberating large quantities of haem. Despite its toxicity, haem is an essential factor for numerous biological reactions, and may be an important iron source for these helminths. We used a fluorescence haem analogue, palladium mesoporphyrin, to investigate pathways of haem acquisition, and showed that palladium mesoporphyrin accumulates in the vitellaria (eggshell precursor glands) and ovary of female Schistosoma mansoni. Furthermore, incubation of adult females in 10-100 μm cyclosporin A (IC50 = 2.3 μm) inhibits the uptake of palladium mesoporphyrin to these tissues, with tenfold reductions in fluorescence intensity of the ovary. In vitro exposure to cyclosporin A resulted in significant perturbation of egg production, reducing egg output from 34 eggs per female to 5.7 eggs per female over the incubation period, and retardation of egg development. We characterized a S. mansoni homologue of the haem-responsive genes of Caenorhabditis elegans. The gene (Smhrg-1) encodes a protein with a molecular weight of approximately 17 kDa. SmHRG-1 was able to rescue growth in haem transport-deficient HEM1Δ yeast. Transcriptional suppression of Smhrg-1 in adult S. mansoni worms resulted in significant delay in egg maturation, with 47% of eggs from transcriptionally suppressed worms being identified as immature compared with only 27% of eggs laid by control worms treated with firefly luciferase. Our findings indicate the presence of transmembrane haem transporters in schistosomes, with a high abundance of these molecules being present in tissues involved in oogenesis.

  13. Reconstructing Colonization Dynamics of the Human Parasite Schistosoma mansoni following Anthropogenic Environmental Changes in Northwest Senegal

    PubMed Central

    Van den Broeck, Frederik; Maes, Gregory E.; Larmuseau, Maarten H. D.; Rollinson, David; Sy, Ibrahima; Faye, Djibril; Volckaert, Filip A. M.; Polman, Katja; Huyse, Tine

    2015-01-01

    Background Anthropogenic environmental changes may lead to ecosystem destabilization and the unintentional colonization of new habitats by parasite populations. A remarkable example is the outbreak of intestinal schistosomiasis in Northwest Senegal following the construction of two dams in the ‘80s. While many studies have investigated the epidemiological, immunological and geographical patterns of Schistosoma mansoni infections in this region, little is known about its colonization history. Methodology/Principal Findings Parasites were collected at several time points after the disease outbreak and genotyped using a 420 bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) and nine nuclear DNA microsatellite markers. Phylogeographic and population genetic analyses revealed the presence of (i) many genetically different haplotypes at the non-recombining mitochondrial marker and (ii) one homogenous S. mansoni genetic group at the recombining microsatellite markers. These results suggest that the S. mansoni population in Northwest Senegal was triggered by intraspecific hybridization (i.e. admixture) between parasites that were introduced from different regions. This would comply with the extensive immigration of infected seasonal agricultural workers from neighboring regions in Senegal, Mauritania and Mali. The spatial and temporal stability of the established S. mansoni population suggests a swift local adaptation of the parasite to the local intermediate snail host Biomphalaria pfeifferi at the onset of the epidemic. Conclusions/Significance Our results show that S. mansoni parasites are very successful in colonizing new areas without significant loss of genetic diversity. Maintaining high levels of diversity guarantees the adaptive potential of these parasites to cope with selective pressures such as drug treatment, which might complicate efforts to control the disease. PMID:26275049

  14. Isolation of cDNA clones for differentially expressed genes of the human parasite Schistosoma mansoni.

    PubMed Central

    Davis, A H; Blanton, R; Rottman, F; Maurer, R; Mahmoud, A

    1986-01-01

    Little is known about the mechanisms that control transformations during the life cycle of Schistosoma mansoni. To enable isolation of DNA sequences encoding developmentally regulated antigens a cDNA expression library in the vector lambda gt11 amp3 was constructed from adult mRNA and immunologically screened with sera from infected individuals. We report here on the properties of three recombinant clones that derive from developmentally regulated genes. Clone 10-3 encoded a beta-galactosidase fusion protein present in high abundance in infected Escherichia coli. Clones 7-2 and 8-2 also produced immunologically recognized proteins; however, the peptides did not appear to be beta-galactosidase fusion proteins. The expression of mRNAs hybridizing to these cDNAs was examined in the different stages of the parasite life cycle. Messenger RNA corresponding to clone 10-3, approximately equal to 1000 bases in length, was present in higher abundance in male worms than in females but was not detected in schistosome eggs. A 900-base mRNA hybridizing to clone 7-2 was observed in adult worms and eggs. Both clone 10-3 and clone 7-2 hybridized to smaller mRNAs in cercariae and freshly transformed schistosomula than in adult worms. Clone 8-2 contained tandem cDNA inserts. One cDNA hybridized to a 1700-base mRNA present in all stages, while the second hybridized to an 800-base mRNA specific to adult female worms. Images PMID:3461448

  15. Magnetic affinity enzyme-linked immunoassay for diagnosis of Schistosomiasis japonicum in persons with low-intensity infection.

    PubMed

    Yu, Qin; Yang, Hai; Feng, Youmei; Zhu, Yanhong; Yang, Xiangliang

    2012-10-01

    Most schistosome-endemic areas in China are characterized by low-intensity infections that are independent of prevalence. To establish an effective diagnostic method, we developed a magnetic affinity enzyme-linked immunoassay based on soluble egg antigens (SEA-MEIA) for diagnosing schistosomiasis in persons with low-intensity infection with Schistosoma japonicum by comparing it with a conventional enzyme-linked immunosorbent assay (ELISA). Our results showed that the SEA-MEIA had a higher sensitivity and greater precision in the diagnosis of low-intensity S. japonicum infections than the ELISA. In addition, when we used Pearson's correlation in associating SEA-MEIA with ELISA, a significant correlation existed between the two assays (r = 0.845, P < 0.001). Our data indicated that SEA-MEIA, with a higher sensitivity and greater ease of performance, would be valuable for diagnosis of schistosomiasis japonicum in persons with low-intensity infections.

  16. Successful parasitism of vector snail Biomphalaria glabrata by the human blood fluke (trematode) Schistosoma mansoni: a 2009 assessment

    PubMed Central

    Bayne, Christopher J.

    2009-01-01

    Schistosomiasis, caused by infections by human blood flukes (Trematoda), continues to disrupt the lives of over 200,000,000 people in over 70 countries, inflicting misery and precluding the individuals’ otherwise reasonable expectations of productive lives. Infection requires contact with freshwater in which infected snails (the intermediate hosts of schistosomes) have released cercariae larvae. Habitats suitable for the host snails continue to expand as a consequence of water resource development. No vaccine is available, and the emergence and spread of resistance to the single licensed schistosomicide drug would be devastating. Since human infections would cease if parasite infections in snails were prevented, efforts are being made to discover requirements of intra-molluscan development of these parasites. Wherever blood flukes occur, naturally resistant conspecific snails are present. To understand the mechanisms used by parasites to ensure their survival in immunocompetent hosts, one must comprehend the internal defense mechanisms that are available to the host. For one intermediate host snail (Biomphalaria glabrata) and trematodes for which it serves as vector, molecular genetic and proteomic surveys for genes and proteins influencing the outcomes on infections are yielding lists of candidates. A comparative approach drawing on data from studies in divergent species provides a robust basis for hypothesis generation to drive decisions as to which candidates merit detailed further investigation. For example, reactive oxygen and nitrogen species are known mediators or effectors in battles between infectious agents and their hosts. An approach targeting genes involved in relevant pathways has been fruitful in the Schistosoma mansoni-B. glabrata parasitism, leading to discovery of a functionally relevant gene set (encoding enzymes responsible for the leukocyte respiratory burst) that associates significantly with host resistance phenotype. This review summarizes

  17. An In-Depth Analysis of a Piece of Shit: Distribution of Schistosoma mansoni and Hookworm Eggs in Human Stool

    PubMed Central

    Krauth, Stefanie J.; Coulibaly, Jean T.; Knopp, Stefanie; Traoré, Mahamadou; N'Goran, Eliézer K.; Utzinger, Jürg

    2012-01-01

    Background An accurate diagnosis of helminth infection is important to improve patient management. However, there is considerable intra- and inter-specimen variation of helminth egg counts in human feces. Homogenization of stool samples has been suggested to improve diagnostic accuracy, but there are no detailed investigations. Rapid disintegration of hookworm eggs constitutes another problem in epidemiological surveys. We studied the spatial distribution of Schistosoma mansoni and hookworm eggs in stool samples, the effect of homogenization, and determined egg counts over time in stool samples stored under different conditions. Methodology Whole-stool samples were collected from 222 individuals in a rural part of south Côte d'Ivoire. Samples were cut into four pieces and helminth egg locations from the front to the back and from the center to the surface were analyzed. Some samples were homogenized and fecal egg counts (FECs) compared before and after homogenization. The effect of stool storing methods on FECs was investigated over time, comparing stool storage on ice, covering stool samples with a water-soaked tissue, or keeping stool samples in the shade. Principal Findings We found no clear spatial pattern of S. mansoni and hookworm eggs in fecal samples. Homogenization decreased S. mansoni FECs (p = 0.026), while no effect was observed for hookworm and other soil-transmitted helminths. Hookworm FECs decreased over time. Storing stool samples on ice or covered with a moist tissue slowed down hookworm egg decay (p<0.005). Conclusions/Significance Our findings have important implications for helminth diagnosis at the individual patient level and for epidemiological surveys, anthelmintic drug efficacy studies and monitoring of control programs. Specifically, homogenization of fecal samples is recommended for an accurate detection of S. mansoni eggs, while keeping collected stool samples cool and moist delayed the disintegration of hookworm eggs. PMID:23285307

  18. Saci-1, -2, and -3 and Perere, Four Novel Retrotransposons with High Transcriptional Activities from the Human Parasite Schistosoma mansoni

    PubMed Central

    DeMarco, Ricardo; Kowaltowski, Andre T.; Machado, Abimael A.; Soares, M. Bento; Gargioni, Cybele; Kawano, Toshie; Rodrigues, Vanderlei; Madeira, Alda M. B. N.; Wilson, R. Alan; Menck, Carlos F. M.; Setubal, João C.; Dias-Neto, Emmanuel; Leite, Luciana C. C.; Verjovski-Almeida, Sergio

    2004-01-01

    Using the data set of 180,000 expressed sequence tags (ESTs) of the blood fluke Schistosoma mansoni generated recently by our group, we identified three novel long-terminal-repeat (LTR)- and one novel non-LTR-expressed retrotransposon, named Saci-1, -2, and -3 and Perere, respectively. Full-length sequences were reconstructed from ESTs and have deduced open reading frames (ORFs) with several uncorrupted features, characterizing them as possible active retrotransposons of different known transposon families. Alignment of reconstructed sequences to available preliminary genome sequence data confirmed the overall structure of the transposons. The frequency of sequenced transposon transcripts in cercariae was 14% of all transcripts from that stage, twofold higher than that in schistosomula and three- to fourfold higher than that in adults, eggs, miracidia, and germ balls. We show by Southern blot analysis, by EST annotation and tallying, and by counting transposon tags from a Social Analysis of Gene Expression library, that the four novel retrotransposons exhibit a 10- to 30-fold lower copy number in the genome and a 4- to 200-fold-higher transcriptional rate per copy than the four previously described S. mansoni retrotransposons. Such differences lead us to hypothesize that there are two different populations of retrotransposons in S. mansoni genome, occupying different niches in its ecology. Examples of retrotransposon fragment inserts were found into the 5′ and 3′ untranslated regions of four different S. mansoni target gene transcripts. The data presented here suggest a role for these elements in the dynamics of this complex human parasite genome. PMID:14990715

  19. Segregation analysis indicates a major gene in the control of interleukine-5 production in humans infected with Schistosoma mansoni.

    PubMed

    Rodrigues, V; Abel, L; Piper, K; Dessein, A J

    1996-08-01

    The interleukine-5 (IL-5) is a hormone of the immune system that is the main regulator of eosinopoiesis, eosinophil maturation and activation, and immunoglobulin A production. Thus, IL-5 contributes in several ways to human immune defenses against various pathogens, including helminths and infectious agents of the digestive and respiratory tracts. On the other hand, the increase in eosinophil number and the activation of these cells, which both have been related to elevated IL-5 production, are the cause of severe pathological disorders, as in asthma or hypereosinophilic syndromes. Although the immunological pathways leading to IL-5 synthesis have been identified, the reasons for the large variability observed in IL-5 production among subjects exposed to comparable antigenic stimulation are unknown. To investigate the role of genetic factors in this variability, we conducted a segregation analysis in a Brazilian population infected by the helminth parasite Schistosoma mansoni. The analysis was performed on IL-5 levels produced by blood mononuclear cells of these subjects after in vitro restimulation with either parasite extracts (IL-5/schistosomula sonicates [SS] phenotype) or a T-lymphocyte mitogen (IL-5/phytohemagglutin [PHA]). The results provide clear evidence for the segregation of a codominant major gene controlling IL-5/SS and IL-5/PHA production and accounting for 70% and 73% of the phenotypic variance, respectively; the frequency of the allele predisposing to low IL-5 production was approximately .22 for both phenotypes. No significant relationship was found between these genes and the gene controlling infection intensities by S. mansoni detected in a previous study. Linkage studies are ongoing to locate those genes that would help to characterize the genetic factors involved in pathological conditions such as severe helminth infections and allergic diseases.

  20. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Schistosoma spp. serological reagents. 866.3600 Section 866.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma...

  1. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Schistosoma spp. serological reagents. 866.3600 Section 866.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma...

  2. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Schistosoma spp. serological reagents. 866.3600 Section 866.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma...

  3. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Schistosoma spp. serological reagents. 866.3600 Section 866.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600 Schistosoma...

  4. Human U6 promoter drives stronger shRNA activity than its schistosome orthologue in Schistosoma mansoni and human fibrosarcoma cells.

    PubMed

    Duvoisin, Raphaël; Ayuk, Mary A; Rinaldi, Gabriel; Suttiprapa, Sutas; Mann, Victoria H; Lee, Clarence M; Harris, Nicola; Brindley, Paul J

    2012-06-01

    Blood flukes or schistosomes are the causative agents of human schistosomiasis, one of the major neglected tropical diseases. Draft genome sequences have been reported for schistosomes, but functional genomics tools are needed to investigate the role and essentiality of the newly reported genes. Vector based RNA interference can contribute to functional genomics analysis for schistosomes. Using mRNA encoding reporter firefly luciferase as a model target, we compared the performance of a schistosome and a human promoter from the U6 gene in driving shRNA in human fibrosarcoma cells and in cultured schistosomes. Further, both a retroviral [Murine leukemia virus (MLV)] and plasmid (piggyBac, pXL-Bac II) vector were utilized. The schistosome U6 gene promoter was 270 bp in length, the human U6 gene promoter was 264 bp; they shared 41% identity. Following transduction of both HT1080 fibrosarcoma cells and schistosomules of Schistosoma mansoni with pseudotyped MLV virions, stronger knockdown of luciferase activity was seen with the virions encoding the human U6 promoter driven shRNA than the schistosome U6 promoter. A similar trend was seen after transfection of HT1080 cells and schistosomules with the pXL-Bac-II constructs-stronger knockdown of luciferase activity was seen with constructs encoding the human compared to schistosome U6 promoter. The findings indicate that a human U6 gene promoter drives stronger shRNA activity than its schistosome orthologue, not only in a human cancer cell line but also in larval schistosomes. This RNA polymerase III promoter represents a potentially valuable component for vector based RNA interference studies in schistosomes and related platyhelminth parasites.

  5. Human U6 promoter drives stronger shRNA activity than its schistosome orthologue in Schistosoma mansoni and human fibrosarcoma cells

    PubMed Central

    Duvoisin, Raphaël; Ayuk, Mary A.; Rinaldi, Gabriel; Suttiprapa, Sutas; Mann, Victoria H.; Lee, Clarence M.; Harris, Nicola; Brindley, Paul J.

    2011-01-01

    Blood flukes or schistosomes are the causative agents of human schistosomiasis, one of the major neglected tropical diseases. Draft genome sequences have been reported for schistosomes, but functional genomics tools are needed to investigate the role and essentiality of the newly reported genes. Vector based RNA interference can contribute to functional genomics analysis for schistosomes. Using mRNA encoding reporter firefly luciferase as a model target, we compared the performance of a schistosome and a human promoter from the U6 gene in driving shRNA in human fibrosarcoma cells and in cultured schistosomes. Further, both a retroviral (Murine leukemia virus [MLV]) and plasmid (piggyBac, pXL-Bac II) vector were utilized. The schistosome U6 gene promoter was 270 bp in length, the human U6 gene promoter was 264 bp; they shared 41% identity. Following transduction of both HT1080 fibrosarcoma cells and schistosomules of Schistosoma mansoni with pseudotyped MLV virions, stronger knockdown of luciferase activity was seen with the virions encoding the human U6 promoter driven shRNA than the schistosome U6 promoter. A similar trend was seen after transfection of HT1080 cells and schistosomules with the pXL-Bac-II constructs – stronger knockdown of luciferase activity was seen with constructs encoding the human compared to schistosome U6 promoter. The findings indicate that a human U6 gene promoter drives stronger shRNA activity than its schistosome orthologue, not only in a human cancer cell line but also in larval schistosomes. This RNA polymerase III promoter represents a potentially valuable component for vector based RNA interference studies in schistosomes and related platyhelminth parasites. PMID:21953124

  6. Molecular and functional characterization of a putative PA28γ proteasome activator orthologue in Schistosoma mansoni.

    PubMed

    Soares, Cláudia Sossai; Morais, Enyara Rezende; Magalhães, Lizandra G; Machado, Carla Botelho; Moreira, Érika Bueno de Carvalho; Teixeira, Felipe Roberti; Rodrigues, Vanderlei; Yoshino, Timothy P

    2013-05-01

    PA28γ is a proteasome activator involved in the regulation of the cellular proliferation, differentiation and growth. In the present study, we identified and characterized a cDNA from Schistosoma mansoni exhibiting significant homology to PA28γ of diverse taxa ranging from mammals (including humans) to simple invertebrates. Designated SmPA28γ, this transcript has a 753bp predicted ORF encoding a protein of 250 amino acid residues. Alignment of SmPA28γ with multiple PA28γ orthologues revealed an average similarity of ~40% among the investigated organisms, and 90% similarity with PA28γ from Schistosoma japonicum. In addition, phylogenetic analysis demonstrated a close linkage between SmPA28γ to its sister group that contains well-characterized PA28γ sequences from Drosophila spp., as well as sharing the same branch with PA28γ from S. japonicum. Gene expression profiling of SmPA28γ using real-time quantitative PCR revealed elevated steady-state transcript levels in the eggs, miracidia and paired adult worms compared to other stages. In parallel with gene expression profiles, an affinity-purified anti-SmPA28γ antibody produced against recombinant protein exhibited strongest reactivity in Western blot analyses to endogenous SmPA28γ from miracidia, sporocysts and paired adult worms. Given its known regulatory function in other organisms, we hypothesized that the high level of SmPA28γ transcript and protein in these stages may be correlated with an important role of the PA28γ in the cellular growth and/or development of this parasite. To address this hypothesis, miracidia were transformed in vitro to sporocysts in the presence of SmPA28γ double-stranded RNAs (dsRNAs) and cultivated for 4 days, after which time steady-state transcript and protein levels, and phenotypic changes were evaluated. SmPA28γ dsRNA treatment resulted in gene and protein knockdown of ~60% and ~80%, respectively, which were correlated with a significant decrease in larval length

  7. Molecular and functional characterization of a putative PA28γ proteasome activator orthologue in Schistosoma mansoni

    PubMed Central

    Soares, Cláudia Sossai; Morais, Enyara Rezende; Magalhães, Lizandra G.; Machado, Carla Botelho; Moreira, Érika Bueno de Carvalho; Teixeira, Felipe Roberti; Rodrigues, Vanderlei; Yoshino, Timothy P.

    2013-01-01

    PA28γ is a proteasome activator involved in the regulation of the cellular proliferation, differentiation and growth. In the present study, we identified and characterized a cDNA from Schistosoma mansoni exhibiting significant homology to PA28γ of diverse taxa ranging from mammals (including humans) to simple invertebrates. Designated SmPA28γ, this transcript has a 753 bp predicted ORF encoding a protein of 250 amino acid residues. Alignment of SmPA28γ with multiple PA28γ orthologues revealed an average similarity of ~40% among the investigated organisms, and 90% similarity with PA28γ from Schistosoma japonicum. In addition, phylogenetic analysis demonstrated a close linkage between SmPA28γ to its sister group that contains well-characterized PA28γ sequences from Drosophila spp., as well as sharing the same branch with PA28γ from S. japonicum. Gene expression profiling of SmPA28γ using real-time quantitative PCR revealed elevated steady-state transcript levels in the eggs, miracidia and paired adult worms compared to other stages. In parallel with gene expression profiles, an affinity-purified anti-SmPA28γ antibody produced against recombinant protein exhibited strongest reactivity in Western blot analyses to endogenous SmPA28γ from miracidia, sporocysts and paired adult worms. Given its known regulatory function in other organisms, we hypothesized that the high level of SmPA28γ transcript and protein in these stages may be correlated with an important role of the PA28γ in the cellular growth and/or development of this parasite. To address this hypothesis, miracidia were transformed in vitro to sporocysts in the presence of SmPA28γ double-stranded RNAs (dsRNAs) and cultivated for 4 days, after which time steady-state transcript and protein levels, and phenotypic changes were evaluated. SmPA28γ dsRNA treatment resulted in gene and protein knockdown of ~60% and ~80%, respectively, which were correlated with a significant decrease in larval length

  8. Evolutionary analysis of the cystatin family in three Schistosoma species

    PubMed Central

    Cuesta-Astroz, Yesid; Scholte, Larissa L. S.; Pais, Fabiano Sviatopolk-Mirsky; Oliveira, Guilherme; Nahum, Laila A.

    2014-01-01

    The cystatin family comprises cysteine protease inhibitors distributed in 3 subfamilies (I25A–C). Family members lacking cystatin activity are currently unclassified. Little is known about the evolution of Schistosoma cystatins, their physiological roles, and expression patterns in the parasite life cycle. The present study aimed to identify cystatin homologs in the predicted proteome of three Schistosoma species and other Platyhelminthes. We analyzed the amino acid sequence diversity focused in the identification of protein signatures and to establish evolutionary relationships among Schistosoma and experimentally validated human cystatins. Gene expression patterns were obtained from different developmental stages in Schistosoma mansoni using microarray data. In Schistosoma, only I25A and I25B proteins were identified, reflecting little functional diversification. I25C and unclassified subfamily members were not identified in platyhelminth species here analyzed. The resulting phylogeny placed cystatins in different clades, reflecting their molecular diversity. Our findings suggest that Schistosoma cystatins are very divergent from their human homologs, especially regarding the I25B subfamily. Schistosoma cystatins also differ significantly from other platyhelminth homologs. Finally, transcriptome data publicly available indicated that I25A and I25B genes are constitutively expressed thus could be essential for schistosome life cycle progression. In summary, this study provides insights into the evolution, classification, and functional diversification of cystatins in Schistosoma and other Platyhelminthes, improving our understanding of parasite biology and opening new frontiers in the identification of novel therapeutic targets against helminthiases. PMID:25071834

  9. [Content of rare earth elements in wild Hypericum japonicum Thunb].

    PubMed

    Wei, Zhen-Lin; Rui, Yu-Kui; Tian, Zhi-Huan

    2009-06-01

    Rare earth elements are important nutritional elements for human health, and today more and more attention has been paid to the effective components in Chinese traditional medicine, especially to rare earth elements. Fifteen rare earth elements in wild hypericum japonicum Thunb were analyzed by the methods of ICP-MS. The results showed that the concentrations of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Tm, Lu and Y ranged from 6 ng x g(-1) x DW to 14 522 ng x g(-1) x DW, and among them the concentrations of La, Ce and Nd were higher than 2 000 ng x g(-1) x DW. Compared with the concentration of rare earth elements in rice, corn, wheat and barley, the total concentration of rare earth elements in hypericum japonicum Thunb was much higher, which could be the mechanism of curative effect of hypericum japonicum Thunb on liverish diseases. The character of elements and the content of rare earth elements in soil should be responsible for the difference, but the distributive mechanism of rare earth elements in hypericum japonicum Thunb should be further studied.

  10. Large-Scale Overproduction and Purification of Recombinant Histone Deacetylase 8 (HDAC8) from the Human-Pathogenic Flatworm Schistosoma mansoni.

    PubMed

    Marek, Martin; Shaik, Tajith B; Duclaud, Sylvie; Pierce, Raymond J; Romier, Christophe

    2016-01-01

    Epigenetic mechanisms underlie the morphological transformations and shifts in virulence of eukaryotic pathogens. The targeting of epigenetics-driven cellular programs thus represents an Achilles' heel of human parasites. Today, zinc-dependent histone deacetylases (HDACs) belong to the most explored epigenetic drug targets in eukaryotic parasites. Here, we describe an optimized protocol for the large-scale overproduction and purification of recombinant smHDAC8, an emerging epigenetic drug target in the multicellular human-pathogenic flatworm Schistosoma mansoni. The strategy employs the robustness of recombinant expression in Escherichia coli together with initial purification through a poly-histidine affinity tag that can be removed by the thrombin protease. This protocol is divided into two steps: (1) large-scale production of smHDAC8 in E. coli, and (2) purification of the target smHDAC8 protein through multiple purification steps.

  11. A late IL-33 response after exposure to Schistosoma haematobium antigen is associated with an up-regulation of IL-13 in human eosinophils

    PubMed Central

    Wilson, S; Jones, F M; Fofana, H K M; Landouré, A; Kimani, G; Mwatha, J K; Sacko, M; Vennervald, B J; Dunne, D W

    2013-01-01

    IL-33, a proposed alarmin, stimulates innate immune cells and Th2 cells to produce IL-13 and is rapidly upregulated upon antigen exposure in murine helminth infection. The human IL-33 response to helminth antigen was analysed in Malians infected with Schistosoma haematobium by disrupting parasite integrity via chemotherapy. Plasma IL-33 was measured pretreatment, and 24 h and 9 weeks post-treatment. At 24 h post-treatment, IL-33 levels were low. Nine week post-treatment IL-33 levels were elevated and were associated with an increase in intracellular IL-13 in eosinophils. Up-regulation of intracellular IL-13 in eosinophils was also associated with eosinophil expression of ST2L, the IL-33 receptor. IL-33 may play an important downstream role in the human response to schistosome adult worm antigen exposure. PMID:23521712

  12. Schistosoma mansoni Infection of Mice, Rats and Humans Elicits a Strong Antibody Response to a Limited Number of Reduction-Sensitive Epitopes on Five Major Tegumental Membrane Proteins

    PubMed Central

    Tremblay, Jacqueline M.; Oliveira, Sergio C.; Da’dara, Akram A.; Skelly, Patrick J.

    2017-01-01

    Schistosomiasis is a major disease of the developing world for which no vaccine has been successfully commercialized. While numerous Schistosoma mansoni worm antigens have been identified that elicit antibody responses during natural infections, little is known as to the identities of the schistosome antigens that are most prominently recognized by antibodies generated through natural infection. Non-reducing western blots probed with serum from schistosome-infected mice, rats and humans on total extracts of larval or adult schistosomes revealed that a small number of antigen bands predominate in all cases. Recognition of each of these major bands was lost when the blots were run under reducing condition. We expressed a rationally selected group of schistosome tegumental membrane antigens in insect host cells, and used the membrane extracts of these cells to unambiguously identify the major antigens recognized by S. mansoni infected mouse, rat and human serum. These results revealed that a limited number of dominant, reduction-sensitive conformational epitopes on five major tegumental surface membrane proteins: SmTsp2, Sm23, Sm29, SmLy6B and SmLy6F, are primary targets of mouse, rat and human S. mansoni infection sera antibodies. We conclude that, Schistosoma mansoni infection of both permissive (mouse) and non-permissive (rat) rodent models, as well as humans, elicit a dominant antibody response recognizing a limited number of conformational epitopes on the same five tegumental membrane proteins. Thus it appears that neither infecting schistosomula nor mature adult schistosomes are substantively impacted by the robust circulating anti-tegumental antibody response they elicit to these antigens. Importantly, our data suggest a need to re-evaluate host immune responses to many schistosome antigens and has important implications regarding schistosome immune evasion mechanisms and schistosomiasis vaccine development. PMID:28095417

  13. Epidemiology of human Schistosoma haematobium infection around Volta Lake, Ghana, 1973-75

    PubMed Central

    Scott, D.; Senker, K.; England, E. C.

    1982-01-01

    There was a dramatic rise in the prevalence of urinary schistosomiasis around Volta Lake within a year of its full impoundment in 1968. Research was undertaken to investigate the epidemiology of the disease in preparation for a control programme. The interplay of three factors—age, sex, and ethnic affiliation—largely defined the demographic patterns of the prevalence and the intensity of infection. Both of these increased in young children up to a peak at age 10-14 years, and then declined, the intensity of infection more rapidly than the prevalence. The prevalence and intensity of infection were both greater in males than females (above ages 15-24 years and 5-9 years, respectively), and differences between the two main ethnic groups were related to differences in their lake-related activities. Differences between the patterns of prevalence and intensity of infection are attributed to the greater sensitivity of the latter measurement in indicating changes in the level of transmission. Practical difficulties were encountered in obtaining a precise measurement of incidence, the most important being the considerable degree of population movement. A field cohort study showed a seasonality of transmission, greatest between January and April, during the period of high level of the lake and in the early part of the draw-down. Research on the intermediate snail host (Bulinus truncatus rohlfsi) and lakeside ecology established the focality of transmission at human water-contact sites serving the shore-line communities and, in conjunction with parasitological surveys, its seasonality: variations in ecology that accompanied the annual rise and fall of the lake led to high levels of transmission when the water level was high and lower levels during the draw-down. The geographical distribution of the infection was also affected by differences in ecology, specifically by variations in the distribution and abundance of the aquatic weed Ceratophyllum demersum. A non

  14. Schistosoma mansoni Soluble Egg Antigens Induce Expression of the Negative Regulators SOCS1 and SHP1 in Human Dendritic Cells via Interaction with the Mannose Receptor

    PubMed Central

    Klaver, Elsenoor J.; Kuijk, Loes M.; Lindhorst, Thisbe K.; Cummings, Richard D.; van Die, Irma

    2015-01-01

    Schistosomiasis is a common debilitating human parasitic disease in (sub)tropical areas, however, schistosome infections can also protect against a variety of inflammatory diseases. This has raised broad interest in the mechanisms by which Schistosoma modulate the immune system into an anti-inflammatory and regulatory state. Human dendritic cells (DCs) show many phenotypic changes upon contact with Schistosoma mansoni soluble egg antigens (SEA). We here show that oxidation of SEA glycans, but not heat-denaturation, abrogates the capacity of SEA to suppress both LPS-induced cytokine secretion and DC proliferation, indicating an important role of SEA glycans in these processes. Remarkably, interaction of SEA glycans with DCs results in a strongly increased expression of Suppressor Of Cytokine Signalling1 (SOCS1) and SH2-containing protein tyrosine Phosphatase-1 (SHP1), important negative regulators of TLR4 signalling. In addition, SEA induces the secretion of transforming growth factor β (TGF-β), and the surface expression of the costimulatory molecules Programmed Death Ligand-1 (PD-L1) and OX40 ligand (OX40L), which are known phenotypic markers for the capacity of DCs to polarize naïve T cells into Th2/Treg cell subsets. Inhibition of mannose receptor (MR)-mediated internalization of SEA into DCs by blocking with allyl α-D-mannoside or anti-MR antibodies, significantly reduced SOCS1 and SHP1 expression. In conclusion, we demonstrate that SEA glycans are essential for induction of enhanced SOCS1 and SHP1 levels in DCs via the MR. Our data provide novel mechanistic evidence for the potential of S. mansoni SEA glycans to modulate human DCs, which may contribute to the capacity of SEA to down-regulate inflammatory responses. PMID:25897665

  15. Trace elements in the human scalp hair and finger nails as affected by infection with Schistosoma mansoni

    NASA Astrophysics Data System (ADS)

    El-Khatib, Ahmed M.; Bahnassy, Ahmed A.; Denton, M.

    1995-01-01

    The concentration of 13 elements has been determined in finger nail and scalp hair of 4 groups representing normal and infected Schistosoma mansoni subjects. Samples were irradiated by thermal neutrons from a Triga Mark III Reactor, for 10 min. Measurements were made using a HPGe detector coupled with ADC and PDP {11}/{34} data processing equipment. The results showed significant increases of Al, Cl, I and Br in both finger nails and scalp hair of bilharzial patients above those of normal subjects while Mg, Ca, V, Mn, Cu, Sr, K, S and Na showed significant decreases. Most of the elements showed a higher concentration in finger nails than in hair.

  16. Expression at a 20L scale and purification of the extracellular domain of the Schistosoma mansoni TSP-2 recombinant protein: a vaccine candidate for human intestinal schistosomiasis.

    PubMed

    Curti, Elena; Kwityn, Clifford; Zhan, Bin; Gillespie, Portia; Brelsford, Jill; Deumic, Vehid; Plieskatt, Jordan; Rezende, Wanderson C; Tsao, Eric; Kalampanayil, Bose; Hotez, Peter J; Bottazzi, Maria Elena

    2013-11-01

    A novel recombinant protein vaccine for human schistosomiasis caused by Schistosoma mansoni is under development. The Sm-TSP-2 schistosomiasis vaccine is comprised of a 9 kDa recombinant protein corresponding to the extracellular domain of a unique S. mansoni tetraspanin. Here, we describe the cloning and the expression of the external loop of Sm-TSP-2 recombinant protein secreted by Pichia Pink the process development at 20L scale fermentation, and the two-steps purification, which resulted in a protein recovery yield of 31% and a protein purity of 97%. The developed processes are suitable for the production of purified protein for subsequent formulation and Phase 1 clinical studies.

  17. Susceptibility or resistance of praziquantel in human schistosomiasis: a review.

    PubMed

    Wang, Wei; Wang, Li; Liang, You-Sheng

    2012-11-01

    Since praziquantel was developed in 1970s, it has replaced other antischistosomal drugs to become the only drug of choice for treatment of human schistosomiases, due to high efficacy, excellent tolerability, few and transient side effects, simple administration, and competitive cost. Praziquantel-based chemotherapy has been involved in the global control strategy of the disease and led to the control strategy shifting from disease control to morbidity control, which has greatly reduced the prevalence and intensity of infections. Given that the drug has been widely used for morbidity control in endemic areas for more than three decades, the emergence of resistance of Schistosoma to praziquantel under drug selection pressure has been paid much attention. It is possible to induce resistance of Schistosoma mansoni and Schistosoma japonicum to praziquantel in mice under laboratorial conditions, and a reduced susceptibility to praziquantel in the field isolates of S. mansoni has been found in many foci. In addition, there are several schistosomiasis cases caused by Schistosoma haematobium infections in which repeated standard treatment fails to clear the infection. However, in the absence of exact mechanisms of action of praziquantel, the mechanisms of drug resistance in schistosomes remain unclear. The present review mainly demonstrates the evidence of drug resistance in the laboratory and field and the mechanism of praziquantel resistance and proposes some strategies for control of praziquantel resistance in schistosomes.

  18. Characterization of thioredoxin glutathione reductase in Schiotosoma japonicum.

    PubMed

    Han, Yanhui; Zhang, Min; Hong, Yang; Zhu, Zhu; Li, Dong; Li, Xiangrui; Fu, Zhiqiang; Lin, Jiaojiao

    2012-09-01

    Schistosomiasis is one of the most prevalent and serious parasitic diseases in the world and remains an important public health problem in China. Screening and discovery of an effective vaccine candidate or new drug target is crucial for the control of this disease. In this study, we cloned a cDNA encoding Schistosoma japonicum (S. japonicum) thioredoxin glutathione reductase (SjTGR) from the cDNA of 42-day-old adult worms. The open reading frame (ORF) of the gene was 1791 base pairs (bp) encoding a protein of 596 amino acids. SjTGR was subcloned into pET-32a (+) and expressed in Escherichia coli (E. coli) BL21 (DE3). The recombinant protein rSjTGR exhibited enzymatic activity of 5.13U/mg with DTNB as the substrate, and showed strong immunogenecity. Real-time PCR results indicated that SjTGR was expressed at a higher level in 35-day-old schistosome worms in transcript. We vaccinated BALB/c mice with rSjTGR in combination with MONTANIDE™ ISA 206 VG (ISA 206) and observed a 33.50% to 36.51% (P<0.01) decrease in the adult worm burden and a 33.73%to 43.44% (P<0.01) decrease in the number of eggs counted compared to the ISA 206 or blank control groups in two independent vaccination tests. ELISA analysis demonstrated that rSjTGR induced a high level of SjTGR-specific IgG, IgG1, and IgG 2a antibodies and induced elevated production of IFN-γ. This study provides the basis for further investigations into the biological function of SjTGR and further evaluation of the potential use of this molecule as a vaccine candidate or new drug target is warranted.

  19. [Schistosoma, water and man].

    PubMed

    Combes, C

    1993-02-15

    The biology of schistosomes is increasingly better known due to the research works conducted since the early 1980s. Numerous data have been collected on: the structure of the genome; the genetic variability of natural populations; the causes of geographical distribution of Schistosoma species; the acquisition, probably recent, of the parasite as by modern man's ancestors; and even some aspects of development, such as the behaviour of larvae and the migrations in the circulatory system. Substantial advances have also been made in the maintenance of laboratory strains. Yet, multiple and fascinating problems are still raised by schistosomes. In the present state of our knowledge the origin and relationship of human parasitizing species are still hypothetical. Several features of reproduction, such as the existence of separate sexes and permanent couples cannot be explained. Quantitative data concerning the dynamics of transmission are much too vague to establish satisfactory mathematical models and to contribute usefully to strategies of control. Finally, the fact that schistosomes can develop either in man alone or in numerous mammals remain a mystery for immunologists and specialists of evolution.

  20. Conservation of symbiotic nitrogen fixation gene sequences in Rhizobium japonicum and Bradyrhizobium japonicum.

    PubMed Central

    Masterson, R V; Prakash, R K; Atherly, A G

    1985-01-01

    Southern hybridization with nif (nitrogen fixation) and nod (nodulation) DNA probes from Rhizobium meliloti against intact plasmid DNA of Rhizobium japonicum and Bradyrhizobium japonicum strains indicated that both nif and nod sequences are on plasmid DNA in most R. japonicum strains. An exception is found with R. japonicum strain USDA194 and all B. japonicum strains where nif and nod sequences are on the chromosome. In R. japonicum strains, with the exception of strain USDA205, both nif and nod sequences are on the same plasmid. In strain USDA205, the nif genes are on a 112-megadalton plasmid, and nod genes are on a 195-megadalton plasmid. Hybridization to EcoRI digests of total DNA to nif and nod probes from R. meliloti show that the nif and nod sequences are conserved in both R. japonicum and B. japonicum strains regardless of the plasmid or chromosomal location of these genes. In addition, nif DNA hybridization patterns were identical among all R. japonicum strains and with most of the B. japonicum strains examined. Similarly, many of the bands that hybridize to the nodulation probe isolated from R. meliloti were found to be common among R. japonicum strains. Under reduced hybridization stringency conditions, strong conservation of nodulation sequences was observed in strains of B. japonicum. We have also found that the plasmid pRjaUSDA193, which possess nif and nod sequences, does not possess sequence homology with any plasmid of USDA194, but is homologous to parts of the chromosome of USDA194. Strain USDA194 is unique, since nif and nod sequences are present on the chromosome instead of on a plasmid as observed with all other strains examined. Images PMID:4008441

  1. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil.

    PubMed

    Barboza, Delmany Moitinho; Zhang, Cangjie; Santos, Nathaly Cardoso; Silva, Marília Matos Bezerra Lemos; Rollemberg, Carla Virgínia Vieira; de Amorim, Fabio Jorge Ramalho; Ueta, Marlene Tiduko; de Melo, Claudia Moura; de Almeida, José Antônio Pacheco; Jeraldo, Verónica de Lourdes Sierpe; de Jesus, Amélia Ribeiro

    2012-09-01

    The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS) was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  2. Schistosoma bovis in western Uganda.

    PubMed

    Stothard, J R; Lockyer, A E; Kabatereine, N B; Tukahebwa, E M; Kazibwe, F; Rollinson, D; Fenwick, A

    2004-09-01

    During routine parasitological surveillance and monitoring activities within a National Control Programme for control of human schistosomiasis in Uganda, it was noted that cattle grazing in a water meadow immediately adjacent to Tonya primary school, where the prevalence of intestinal schistosomiasis in children was in excess of 90%, were unusually emaciated. To test the hypothesis that there may have been an anthropozoonotic focus of Schistosoma mansoni within the local herd, a young female heifer, clearly emaciated and c. 8 months old, was slaughtered from which schistosome worms were later recovered by dissection. As female worms inspected by microscopy were not gravid, morphological identification proved inconclusive but analysis of cytochrome oxidase subunit I (COI) and small subunit (SSU) ribosomal DNA sequences from these worms identified them as Schistosoma bovis Sonsino, 1876. This is the first substantiated report of S. bovis from Lake Albert, western Uganda. Further epidemiological surveys are needed to clarify the extent of bovine schistosomiasis within this region, particularly so since this lakeside plain has been earmarked as a future game reserve.

  3. Enhancement of human eosinophil- and neutrophil-mediated killing of schistosomula of schistosoma mansoni by reversed type (IgE-mediated) anaphylaxis, in vitro

    PubMed Central

    Moqbel, R.; Macdonald, A. J.; Kay, A. B.

    1985-01-01

    Using human peripheral blood leucocytes we have developed a model for studying the effect of in vitro anaphylaxis on granulocyte-mediated killing of helminthic larvae (schistosomula (Sch) of Schistosoma mansoni). Leucocytes were incubated with either an F(ab')2 rabbit anti-human IgE (αE) or a control F(ab')2 prepared from non-specific rabbit IgG (αEc). A time-dependent enhancement of eosinophil- and neutrophil-mediated complement (C) or antibody- (Ab) dependent killing of Sch was observed following incubation with αE, but not αEc. Optimal enhancement of granulocyte killing was dependent on the concentration of αE, pre-incubation of granulocytes with αE prior to addition to C coated Sch, as well as the granulocyte:Sch ratio. Baseline killing of Ab and/or C coated Sch by eosinophil rich cells was significantly greater than neutrophil rich suspensions and both were proportionally increased following incubation with αE. Enhanced eosinophil and neutrophil killing by αE required the presence of mononuclear cells containing basophils, whereas there was no difference in the killing of C or Ab coated Sch when eosinophils or neutrophils alone were incubated with αE or αEc. This IgE and leucocyte-dependent model might facilitate the isolation and identification of the pharmacological mediator(s) of hypersensitivity which enhance eosinophil or neutrophil killing of appropriately opsonized helminthic larvae. PMID:3987093

  4. The Substrate-free and -bound Crystal Structures of the Duplicated Taurocyamine Kinase from the Human Parasite Schistosoma mansoni*

    PubMed Central

    Merceron, Romain; Awama, Ayman M.; Montserret, Roland; Marcillat, Olivier; Gouet, Patrice

    2015-01-01

    The taurocyamine kinase from the blood fluke Schistosoma mansoni (SmTK) belongs to the phosphagen kinase (PK) family and catalyzes the reversible Mg2+-dependent transfer of a phosphoryl group between ATP and taurocyamine. SmTK is derived from gene duplication, as are all known trematode TKs. Our crystallographic study of SmTK reveals the first atomic structure of both a TK and a PK with a bilobal structure. The two unliganded lobes present a canonical open conformation and interact via their respective C- and N-terminal domains at a helix-mediated interface. This spatial arrangement differs from that observed in true dimeric PKs, in which both N-terminal domains make contact. Our structures of SmTK complexed with taurocyamine or l-arginine compounds explain the mechanism by which an arginine residue of the phosphagen specificity loop is crucial for substrate specificity. An SmTK crystal was soaked with the dead end transition state analog (TSA) components taurocyamine-NO32−-MgADP. One SmTK monomer was observed with two bound TSAs and an asymmetric conformation, with the first lobe semiclosed and the second closed. However, isothermal titration calorimetry and enzyme kinetics experiments showed that the two lobes function independently. A small angle x-ray scattering model of SmTK-TSA in solution with two closed active sites was generated. PMID:25837252

  5. Ethanol Extract of Cirsium japonicum var. ussuriense Kitamura Exhibits the Activation of Nuclear Factor Erythroid 2-Related Factor 2-dependent Antioxidant Response Element and Protects Human Keratinocyte HaCaT Cells Against Oxidative DNA Damage

    PubMed Central

    Yoo, Ok-Kyung; Choi, Bu Young; Park, Jin-Oh; Lee, Ji-Won; Park, Byoung-Kwon; Joo, Chul Gue; Heo, Hyo-Jung; Keum, Young-Sam

    2016-01-01

    Keratinocytes are constantly exposed to extracellular insults, such as ultraviolet B, toxic chemicals and mechanical stress, all of which can facilitate the aging of keratinocytes via the generation of intracellular reactive oxygen species (ROS). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that plays a critical role in protecting keratinocytes against oxidants and xenobiotics by binding to the antioxidant response element (ARE), a cis-acting element existing in the promoter of most phase II cytoprotective genes. In the present study, we have attempted to find novel ethanol extract(s) of indigenous plants of Jeju island, Korea that can activate the Nrf2/ARE-dependent gene expression in human keratinocyte HaCaT cells. As a result, we identified that ethanol extract of Cirsium japonicum var. ussuriense Kitamura (ECJUK) elicited strong stimulatory effect on the ARE-dependent gene expression. Supporting this observation, we found that ECJUK induced the expression of Nrf2, hemoxygenase-1, and NAD(P)H:quinone oxidoreductase-1 and this event was correlated with Akt1 phosphorylation. We also found that ECJUK increased the intracellular reduced glutathione level and suppressed 12-O-tetradecanoylphorbol acetate-induced 8-hydroxyguanosine formation without affecting the overall viability. Collectively, our results provide evidence that ECJUK can protect against oxidative stress-mediated damages through the activation of Nrf2/ARE-dependent phase II cytoprotective gene expression. PMID:27051652

  6. Monoclonal antibody-based dipstick assay: a reliable field applicable technique for diagnosis of Schistosoma mansoni infection using human serum and urine samples.

    PubMed

    Demerdash, Zeinab; Mohamed, Salwa; Hendawy, Mohamed; Rabia, Ibrahim; Attia, Mohy; Shaker, Zeinab; Diab, Tarek M

    2013-02-01

    A field applicable diagnostic technique, the dipstick assay, was evaluated for its sensitivity and specificity in diagnosing human Schistosoma mansoni infection. A monoclonal antibody (mAb) against S. mansoni adult worm tegumental antigen (AWTA) was employed in dipstick and sandwich ELISA for detection of circulating schistosome antigen (CSA) in both serum and urine samples. Based on clinical and parasitological examinations, 60 S. mansoni-infected patients, 30 patients infected with parasites other than schistosomiasis, and 30 uninfected healthy individuals were selected. The sensitivity and specificity of dipstick assay in urine samples were 86.7% and 90.0%, respectively, compared to 90.0% sensitivity and 91.7% specificity of sandwich ELISA. In serum samples, the sensitivity and specificity were 88.3% and 91.7% for dipstick assay vs. 91.7% and 95.0% for sandwich ELISA, respectively. The diagnostic efficacy of dipstick assay in urine and serum samples was 88.3% and 90.0%, while it was 90.8% and 93.3% for sandwich ELISA, respectively. The diagnostic indices of dipstick assay and ELISA either in serum or in urine were statistically comparable (P>0.05). In conclusion, the dipstick assay offers an alternative simple, rapid, non-invasive technique in detecting CSA or complement to stool examinations especially in field studies.

  7. Monoclonal Antibody-Based Dipstick Assay: A Reliable Field Applicable Technique for Diagnosis of Schistosoma mansoni Infection Using Human Serum and Urine Samples

    PubMed Central

    Demerdash, Zeinab; Mohamed, Salwa; Hendawy, Mohamed; Rabia, Ibrahim; Attia, Mohy; Shaker, Zeinab

    2013-01-01

    A field applicable diagnostic technique, the dipstick assay, was evaluated for its sensitivity and specificity in diagnosing human Schistosoma mansoni infection. A monoclonal antibody (mAb) against S. mansoni adult worm tegumental antigen (AWTA) was employed in dipstick and sandwich ELISA for detection of circulating schistosome antigen (CSA) in both serum and urine samples. Based on clinical and parasitological examinations, 60 S. mansoni-infected patients, 30 patients infected with parasites other than schistosomiasis, and 30 uninfected healthy individuals were selected. The sensitivity and specificity of dipstick assay in urine samples were 86.7% and 90.0%, respectively, compared to 90.0% sensitivity and 91.7% specificity of sandwich ELISA. In serum samples, the sensitivity and specificity were 88.3% and 91.7% for dipstick assay vs. 91.7% and 95.0% for sandwich ELISA, respectively. The diagnostic efficacy of dipstick assay in urine and serum samples was 88.3% and 90.0%, while it was 90.8% and 93.3% for sandwich ELISA, respectively. The diagnostic indices of dipstick assay and ELISA either in serum or in urine were statistically comparable (P>0.05). In conclusion, the dipstick assay offers an alternative simple, rapid, non-invasive technique in detecting CSA or complement to stool examinations especially in field studies. PMID:23467705

  8. Thermostability of heterophile antibodies from human sera infected with Schistosoma mansoni and geo-helminths. An immuno-metric statistical analysis.

    PubMed

    Chamone, Munir; Atuncar, Gregorio S; Coelho, Paulo Marcos Zech

    2006-01-01

    Antibody in human sera that induces lysis of sheep erythrocytes in hemolytic assay was investigated. The present study showed that the presence in serum of the thermostable cytolytic anti-sheep red blood cells antibodies is dependent on the Schistosoma mansoni infection, and this is more frequent in adults than in children. The thermostable characteristic of hemolysins in normal sera was not dependent on the presence of Ascaris lumbricoides, Trichuris trichiura or hookworm geo-helminths. Further, thermostable complement-activating heterophile antibodies were noticed in children in association with massive number of S. mansoni eggs. The results were obtained by using the z- and the chi-square tests. The z-test allows us to formulate a one-sided alternative, i.e., a tendency of one of the attributes. On the other hand, the chi-square test analyzes the independence between attributes by using a contingency table. Besides the obtained results being interesting in the field of schistosomiasis mansoni, they can provide a new insight into the use of statistics in medical science.

  9. Enzyme analysis of Schistosoma haematobium*

    PubMed Central

    Wright, C. A.; Ross, G. C.

    1983-01-01

    Results are reported of enzyme analyses, by isoelectric focusing in polyacrylamide gels, of adult Schistosoma haematobium worms derived from 22 isolates originating from 13 countries. Polymorphisms have been identified in the glucose-6-phosphate dehydrogenase (G6PD) and phosphoglucomutase (PGM) systems. Certain forms appear to be restricted in their geographical distribution and their occurrence outside their usual areas suggests human population movements resulting in mixing of parasite strains. The possible implications of minor variations in some PGM patterns and the apparent absence of heteropolymer fractions in presumed G6PD heterozygotes are discussed. The use of the technique to detect natural multiple miracidial infections in snails is reported and discussed. ImagesFig. 1 PMID:6222843

  10. Comparison of the differential expression miRNAs in Wistar rats before and 10 days after S.japonicum infection

    PubMed Central

    2013-01-01

    Background When compared to the murine permissive host of Schistosoma japonicum, Wistar rats are less susceptible to Schistosoma japonicum infection, and are considered to provide a less suitable microenvironment for parasite growth and development. MicroRNAs (miRNAs), are a class of endogenous, non-coding small RNAs, that impose an additional, highly significant, level of gene regulation within eukaryotes. Methods To investigate the regulatory mechanisms provided by miRNA in the schistosome-infected rat model, we utilized a miRNA microarray to compare the progression of miRNA expression within different host tissues both before and 10 days after cercarial infection, in order to identify potential miRNAs with roles in responding to a schistosome infection. Results Among the analysed miRNAs, 16 within the liver, 61 within the spleen and 10 within the lung, were differentially expressed in infected Wistar rats. Further analysis of the differentially expressed miRNAs revealed that many important signal pathways are triggered after infection with S. japonicum in Wistar rats. These include the signal transduction mechanisms associated with the Wnt and MAPK signaling pathways, cellular differentiation, with a particular emphasis on adipocyte and erythroid differentiation. Conclusions The results presented here include the identification of specific differentially expressed miRNAs within the liver, lungs and spleen of Wistar rats. These results highlighted the function of host miRNA regulation during an active schistosome infection. Our study provides a better understanding of the regulatory role of miRNA in schistosome infection, and host–parasite interactions in a non-permissive host environment. PMID:23617945

  11. Nickel uptake in Bradyrhizobium japonicum

    SciTech Connect

    Stults, L.W.; Mallick, S.; Maier, R.J.

    1987-04-01

    Free-living Bradyrhizobium japonicum grown heterotrophically with 1 ..mu..M /sup 63/Ni/sup 2 +/ accumulated label. Strain SR470, a Hup/sup c/ mutant, accumulated almost 10-fold more /sup 63/Ni/sup 2 +/ on a per-cell basis than did strain SR, the wild type. Nongrowing cells were also able to accumulate nickel over a 2-h period, with the Hup/sup c/ mutant strain SR470 again accumulating significantly more /sup 63/Ni/sup 2 +/ than strain SR. These results suggest that this mutant is constitutive for nickel uptake as well as for hydrogenase expression. The uptake process was relatively specific for nickel; only Cu/sup 2 +/ and Zn/sup 2 +/ (10 ..mu..M) were found to appreciably inhibit the uptake of 1 ..mu..M Ni, while a 10-fold excess of Mg/sup 2 +/, Co/sup 2 +/, Fe/sup 3 +/, or Mn/sup 2 +/ did not affect Ni/sup 2 +/ uptake. The lack of inhibition by Mg/sup 2 +/ indicates that nickel is not transported by a magnesium uptake system. Nickel uptake was also inhibited by cold and slightly by the ionophores nigericin and carbonyl cyanide m-chlorophenylhydrazone. The cytochrome c oxidase inhibitors azide, cyanide, and hydroxylamine did not inhibit Ni/sup 2 +/ uptake, even at concentrations (of cyanide and hydroxylamine) that inhibited O/sub 2/ uptake. The addition of oxidizable substrates such as succinate or gluconate did not increase nickel uptake, even though they increased respiratory activity. Nickel uptake showed a pH dependence with an optimum at 6.0. Most (approximately 85%) of the /sup 63/Ni/sup 2 +/ taken up in 1 min by strain SR470 was not exchangeable with cold nickel.

  12. Intestinal schistosomiasis caused by both Schistosoma intercalatum and Schistosoma mansoni.

    PubMed

    Tzanetou, Konstantina; Astriti, Myrto; Delis, Vassilios; Moustakas, George; Choreftaki, Theodosia; Papaliodi, Eugenia; Sarri, Katerina; Adamis, George

    2010-05-01

    A case is presented of intestinal schistosomiasis due to both Schistosoma intercalatum and Schistosoma mansoni in a 30-year-old man from Senegal with discussion of diagnostic approach, species identification and determination of the effect of treatment. The patient was admitted to hospital for investigation of renal failure, arterial hypertension and hypereosinophilia. Repeated stool examinations for ova and parasites were negative. Ultrasonography (US) and computed tomography (CT) of the abdomen showed no abnormalities. US of the urinary tract showed kidneys of borderline size with increased echogenicity. Cystoscopy and histopathological examination of bladder biopsy specimens were normal. Flexible colonoscopy revealed numerous nodular lesions in the rectosigmoid region and a few similar lesions in the transverse colon, the histopathological examination of which showed deposition of Schistosoma ova with granuloma formation. Examination of multiple crush biopsy specimens from the rectosigmoid region revealed numerous granulomas formed around Schistosoma eggs which had a terminal spine and were identified as S. intercalatum (longer than Schistosoma haematobium and with a slightly curved terminal spine) and a very few S. mansoni eggs. Crush biopsies from the lesions in the transverse colon showed only S. mansoni eggs. In conclusion, the examination of multiple crush biopsy specimens is a very sensitive and specific technique for species identification of Schistosoma, especially in mixed infections, and for defining the location and extent of the granulomas evoked by each species.

  13. CA88, a nuclear repetitive DNA sequence identified in Schistosoma mansoni, aids in the genotyping of nine Schistosoma species of medical and veterinary importance.

    PubMed

    Bahia, Diana; Rodrigues, Nilton B; Araújo, Flávio Marcos G; Romanha, Alvaro José; Ruiz, Jerônimo C; Johnston, David A; Oliveira, Guilherme

    2010-07-01

    CA88 is the first long nuclear repetitive DNA sequence identified in the blood fluke, Schistosoma mansoni. The assembled S. mansoni sequence, which contains the CA88 repeat, has 8,887 nucleotides and at least three repeat units of approximately 360 bp. In addition, CA88 also possesses an internal CA microsatellite, identified as SmBr18. Both PCR and BLAST analysis have been used to analyse and confirm the CA88 sequence in other S. mansoni sequences in the public database. PCR-acquired nuclear repetitive DNA sequence profiles from nine Schistosoma species were used to classify this organism into four genotypes. Included among the nine species analysed were five sequences of both African and Asian lineages that are known to infect humans. Within these genotypes, three of them refer to recognised species groups. A panel of four microsatellite loci, including SmBr18 and three previously published loci, has been used to characterise the nine Schistosoma species. Each species has been identified and classified based on its CA88 DNA fingerprint profile. Furthermore, microsatellite sequences and intra-specific variation have also been observed within the nine Schistosoma species sequences. Taken together, these results support the use of these markers in studying the population dynamics of Schistosoma isolates from endemic areas and also provide new methods for investigating the relationships between different populations of parasites. In addition, these data also indicate that Schistosoma magrebowiei is not a sister taxon to Schistosoma mattheei, prompting a new designation to a basal clade.

  14. Significant variance in genetic diversity among populations of Schistosoma haematobium detected using microsatellite DNA loci from a genome-wide database

    PubMed Central

    2013-01-01

    Background Urogenital schistosomiasis caused by Schistosoma haematobium is widely distributed across Africa and is increasingly being targeted for control. Genome sequences and population genetic parameters can give insight into the potential for population- or species-level drug resistance. Microsatellite DNA loci are genetic markers in wide use by Schistosoma researchers, but there are few primers available for S. haematobium. Methods We sequenced 1,058,114 random DNA fragments from clonal cercariae collected from a snail infected with a single Schistosoma haematobium miracidium. We assembled and aligned the S. haematobium sequences to the genomes of S. mansoni and S. japonicum, identifying microsatellite DNA loci across all three species and designing primers to amplify the loci in S. haematobium. To validate our primers, we screened 32 randomly selected primer pairs with population samples of S. haematobium. Results We designed >13,790 primer pairs to amplify unique microsatellite loci in S. haematobium, (available at http://www.cebio.org/projetos/schistosoma-haematobium-genome). The three Schistosoma genomes contained similar overall frequencies of microsatellites, but the frequency and length distributions of specific motifs differed among species. We identified 15 primer pairs that amplified consistently and were easily scored. We genotyped these 15 loci in S. haematobium individuals from six locations: Zanzibar had the highest levels of diversity; Malawi, Mauritius, Nigeria, and Senegal were nearly as diverse; but the sample from South Africa was much less diverse. Conclusions About half of the primers in the database of Schistosoma haematobium microsatellite DNA loci should yield amplifiable and easily scored polymorphic markers, thus providing thousands of potential markers. Sequence conservation among S. haematobium, S. japonicum, and S. mansoni is relatively high, thus it should now be possible to identify markers that are universal among Schistosoma

  15. Human lipoprotein binding to schistosomula of schistosoma mansoni. Displacement by polyanions, parasite antigen masking, and persistence in young larvae.

    PubMed Central

    Chiang, C. P.; Caulfield, J. P.

    1989-01-01

    It was previously shown by the authors that the binding of human low-density lipoprotein (LDL) to the surface of schistosomula inhibits the binding of human anti-schistosomal antibodies and is inhibited by suramin. Here, three questions were considered. 1) Are LDLs bound to schistosomula displaced from the membrane by polyanions? 2) Does bound LDL mask or hide antigens recognized by human anti-schistosomal antibodies? 3) Is LDL, binding capability present when the larvae enter the blood stream? The first question was tested by measuring the percentage of the schistosomular surface membrane covered by LDL after exposure to LDL with or without dextran sulfate or suramin. The bound LDL was visualized with polyclonal goat anti-human apolipoprotein B (anti-apo B) antibodies and peroxidase-conjugated secondary antibodies. After overnight culture in 20 micrograms/300 microliters LDL, 84.0% +/- 0.3% of the parasite surface was covered by LDL reaction product. When the polyanions suramin or dextran sulfate were added to the cultures for 30 minutes, only 59.7% +/- 4.9% of the surface was covered by reaction product, demonstrating that the LDL was partially displaced from the membrane by these compounds. The second question was tested by measuring the binding of human and mouse monoclonal anti-schistosomal antibodies before and after exposure to LDL, with or without partial removal of the bound LDL by suramin. LDL partially inhibited antibody binding in a reversible fashion. The LDL clearly masked parasite antigens, most probably by steric hindrance. However, there may be competitive inhibition of antibody binding by the LDL as well, because human anti-schistosomal antibodies inhibited LDL binding to worms and both human anti-schistosomal antibody and LDL binding to schistosomula were inhibited by suramin. Finally, the third question was tested by quantitative immunofluorescence. The LDL binding capability persisted and nearly doubled by 72 hours after transformation from

  16. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements.

    PubMed

    Copeland, Claudia S; Mann, Victoria H; Morales, Maria E; Kalinna, Bernd H; Brindley, Paul J

    2005-02-23

    Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT), RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs representing transcripts of Sinbad in numerous

  17. The Sinbad retrotransposon from the genome of the human blood fluke, Schistosoma mansoni, and the distribution of related Pao-like elements

    PubMed Central

    Copeland, Claudia S; Mann, Victoria H; Morales, Maria E; Kalinna, Bernd H; Brindley, Paul J

    2005-01-01

    Background Of the major families of long terminal repeat (LTR) retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT), RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs representing transcripts of Sinbad

  18. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs*

    PubMed Central

    Smit, Cornelis H.; van Diepen, Angela; Nguyen, D. Linh; Wuhrer, Manfred; Hoffmann, Karl F.; Deelder, André M.; Hokke, Cornelis H.

    2015-01-01

    Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles of glycans and antigenic glycan-motifs during a range of critical stages of the complex schistosome lifecycle. We performed a longitudinal profiling study covering schistosome glycosylation throughout worm- and egg-development using a mass spectrometry-based glycomics approach. Our study revealed that during worm development N-glycans with Galβ1–4(Fucα1–3)GlcNAc (LeX) and core-xylose motifs were rapidly lost after cercariae to schistosomula transformation, whereas GalNAcβ1–4GlcNAc (LDN)-motifs gradually became abundant and predominated in adult worms. LeX-motifs were present on glycolipids up to 2 weeks of schistosomula development, whereas glycolipids with mono- and multifucosylated LDN-motifs remained present up to the adult worm stage. In contrast, expression of complex O-glycans diminished to undetectable levels within days after transformation. During egg development, a rich diversity of N-glycans with fucosylated motifs was expressed, but with α3-core fucose and a high degree of multifucosylated antennae only in mature eggs and miracidia. N-glycan antennae were exclusively LDN-based in miracidia. O-glycans in the mature eggs were also diverse and contained LeX- and multifucosylated LDN, but none of these were associated with miracidia in which we detected only the Galβ1–3(Galβ1–6)GalNAc core glycan. Immature eggs also exhibited short O-glycan core structures only, suggesting that complex fucosylated O-glycans of schistosome eggs are derived primarily from glycoproteins produced by the subshell envelope in the developed egg. Lipid glycans with multifucosylated GlcNAc repeats were present throughout egg development, but with the longer highly

  19. Nitrogen fixation (nif) genes and large plasmids of Rhizobium japonicum.

    PubMed Central

    Masterson, R V; Russell, P R; Atherly, A G

    1982-01-01

    The location of structural nitrogen-fixation genes was determined for the slow- and fast-growing types of Rhizobium japonicum. Slow-growing R. japonicum strains do not harbor structural nif genes, homologous to nifD and nifH, on large plasmids (100 to 200 megadaltons). In contrast, all fast-growing R. japonicum strains, except PRC194, contain structural nif genes on large plasmids. Images PMID:7130134

  20. Identification and characterization of endogenous viral elements for the three key schistosomes of humans.

    PubMed

    Li, Na; Li, Quhuan

    2015-01-01

    Endogenous viral elements (EVEs) are widely distributed throughout eukaryotic genomes, and their evolution and potential function have attracted a lot of interest. Draft genome sequences for Schistosoma mansoni, Schistosoma japonicum and Schistosoma haematobium are now available; however, information about EVEs in blood flukes of the genus schistosoma is scanty. Here, genome-wide survey into the putative EVE sequences of the three key schistosome genomes were present. Totally 4, 117 gene sequences were identified, including retrovirus-like gypsy elements, RNA viruses and dsDNA viruses. Compared with S. japonicum and S. haematobium, S. mansoni appeared to greatly out numbered by gypsy members. Phylogenetic analysis revealed one novel endogenous retrovirus element in S. mansoni. This initial characterization of schistosomes showed that schistosomes harbour distinct EVEs that may have played an important evolutionary role. Studies of schistosomes' endogenous viruses helped us to glance at an earlier viral event in the class Trematoda, greatly broadening the field of palaeovirology.

  1. 21 CFR 866.3600 - Schistosoma spp. serological reagents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Schistosoma spp. serological reagents. 866.3600 Section 866.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3600...

  2. Risk Transmission Indicator of Schistosomiasis Japonicum Considering Human Activities in Lake and Marshland Regions- A Case Study of Poyang Lake, Jiangxi Province, P.R. China

    NASA Astrophysics Data System (ADS)

    Marie, Tiphanie; Yesou, Herve; Huber, Claire; De Fraipont, Paul; Uribe, Carlos; Lacaux, Jean-Pierre; Lafaye, Murielle; Lai, Xijun; Desnos, Yves-Louis

    2013-01-01

    This paper present the method used to determine the areas where schistosomiasis transmission is the higher. A primary work was necessary to this study: identification of potential presence of schistosomiasis japonicum’s vector in Poyang lakeshore area (Jiangxi Province, P.R. China). Results obtained from its first work were crossing with the most risky human activities and with villages to elaborate a level of transmission risk. The first parameter determined concern fishing, which was identified like the most risky activity for schistosomiasis transmission, and fish traps were digitalized using a very high resolution ALOS data. The second parameter is about the risky areas for buffalo grazing, and vector potential presence areas were crossed with village proximity to determine the most risky areas for human transmission. The third parameter built is a level of risk for each village digitalized around Poyang Lake, taking into account the proximity and level of potential presence of vector’s areas.

  3. Bioactive constituents of Cirsium japonicum var. australe.

    PubMed

    Lai, Wan-Chun; Wu, Yang-Chang; Dankó, Balázs; Cheng, Yuan-Bin; Hsieh, Tusty-Jiuan; Hsieh, Chi-Ting; Tsai, Yu-Chi; El-Shazly, Mohamed; Martins, Ana; Hohmann, Judit; Hunyadi, Attila; Chang, Fang-Rong

    2014-07-25

    Cirsium japonicum var. australe, used as a folk medicine in Taiwan, has been employed traditionally in the treatment of diabetes and inflammatory symptoms. Bioactivity-guided fractionation of its ethanolic extract, utilizing centrifugal partition chromatography monitored by DPPH-TLC analysis, led to the isolation of three new acetylenic phenylacrylic acid esters (1-3) and two new polyacetylenes (4 and 5), together with seven known compounds (6-12). The structures of 1-5 were elucidated by spectroscopic methods including 1D and 2D NMR techniques. The absolute configurations of 4 and 7 were determined utilizing Mosher's method and ECD/CD experiments. The DPPH scavenging activity of the constituents isolated from the C. japonicum var. australe ethanolic extract was evaluated. The potential antidiabetic activity of some of the isolates was evaluated using in vitro cellular glucose uptake and oil red staining assays.

  4. Adult Schistosoma mansoni express cathepsin L proteinase activity.

    PubMed

    Smith, A M; Dalton, J P; Clough, K A; Kilbane, C L; Harrop, S A; Hole, N; Brindley, P J

    1994-09-01

    This report presents the deduced amino acid sequence of a novel cathepsin L proteinase from Schistosoma mansoni, and describes cathepsin L-like activity in extracts of adult schistosomes. Using consensus primers specific for cysteine proteinases, gene fragments were amplified from adult S. mansoni cDNA by PCR and cloned. One of these fragments showed marked identity to Sm31, the cathepsin B cysteine proteinase of adult S. mansoni, whereas another differed from Sm31 and was employed as a probe to isolate two cDNAs from an adult S. mansoni gene library. Together these cDNAs encoded a novel preprocathepsin L of 319 amino acids; this zymogen is predicted to be processed in vivo into a mature, active cathepsin L proteinase of 215 amino acids. Closest homologies were with cathepsins L from rat, mouse, and chicken (46-47% identity). Southern hybridization analysis suggested that only one or a few copies of the gene was present per genome, demonstrated that its locus was distinct from that of Sm31, and that a homologous sequence was present in Schistosoma japonicum. Because these results indicated that schistosomes expressed a cathepsin L proteinase, extracts of adult S. mansoni were examined for acidic, cysteine proteinase activity. Based on rates of cleavage of peptidyl substrates employed to discriminate between classes of cysteine proteinases, namely cathepsin L (Z-phe-arg-AMC), cathepsin B (Z-arg-arg-AMC) and cathepsin H (Bz-arg-AMC), the extracts were found to contain vigorous cathepsin L-like activity.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Carbon Monoxide Dehydrogenase Activity in Bradyrhizobium japonicum

    PubMed Central

    Lorite, María J.; Tachil, Jörg; Sanjuán, Juán; Meyer, Ortwin; Bedmar, Eulogio J.

    2000-01-01

    Bradyrhizobium japonicum strain 110spc4 was capable of chemolithoautotrophic growth with carbon monoxide (CO) as a sole energy and carbon source under aerobic conditions. The enzyme carbon monoxide dehydrogenase (CODH; EC 1.2.99.2) has been purified 21-fold, with a yield of 16% and a specific activity of 58 nmol of CO oxidized/min/mg of protein, by a procedure that involved differential ultracentrifugation, anion-exchange chromatography, hydrophobic interaction chromatography, and gel filtration. The purified enzyme gave a single protein and activity band on nondenaturing polyacrylamide gel electrophoresis and had a molecular mass of 230,000 Da. The 230-kDa enzyme was composed of large (L; 75-kDa), medium (M; 28.4-kDa), and small (S; 17.2-kDa) subunits occurring in heterohexameric (LMS)2 subunit composition. The 75-kDa polypeptide exhibited immunological cross-reactivity with the large subunit of the CODH of Oligotropha carboxidovorans. The B. japonicum enzyme contained, per mole, 2.29 atoms of Mo, 7.96 atoms of Fe, 7.60 atoms of labile S, and 1.99 mol of flavin. Treatment of the enzyme with iodoacetamide yielded di(carboxamidomethyl)molybdopterin cytosine dinucleotide, identifying molybdopterin cytosine dinucleotide as the organic portion of the B. japonicum CODH molybdenum cofactor. The absorption spectrum of the purified enzyme was characteristic of a molybdenum-containing iron-sulfur flavoprotein. PMID:10788353

  6. Carbon monoxide dehydrogenase activity in Bradyrhizobium japonicum.

    PubMed

    Lorite, M J; Tachil, J; Sanjuán, J; Meyer, O; Bedmar, E J

    2000-05-01

    Bradyrhizobium japonicum strain 110spc4 was capable of chemolithoautotrophic growth with carbon monoxide (CO) as a sole energy and carbon source under aerobic conditions. The enzyme carbon monoxide dehydrogenase (CODH; EC 1.2.99.2) has been purified 21-fold, with a yield of 16% and a specific activity of 58 nmol of CO oxidized/min/mg of protein, by a procedure that involved differential ultracentrifugation, anion-exchange chromatography, hydrophobic interaction chromatography, and gel filtration. The purified enzyme gave a single protein and activity band on nondenaturing polyacrylamide gel electrophoresis and had a molecular mass of 230,000 Da. The 230-kDa enzyme was composed of large (L; 75-kDa), medium (M; 28.4-kDa), and small (S; 17.2-kDa) subunits occurring in heterohexameric (LMS)(2) subunit composition. The 75-kDa polypeptide exhibited immunological cross-reactivity with the large subunit of the CODH of Oligotropha carboxidovorans. The B. japonicum enzyme contained, per mole, 2.29 atoms of Mo, 7.96 atoms of Fe, 7.60 atoms of labile S, and 1.99 mol of flavin. Treatment of the enzyme with iodoacetamide yielded di(carboxamidomethyl)molybdopterin cytosine dinucleotide, identifying molybdopterin cytosine dinucleotide as the organic portion of the B. japonicum CODH molybdenum cofactor. The absorption spectrum of the purified enzyme was characteristic of a molybdenum-containing iron-sulfur flavoprotein.

  7. Carbohydrate metabolism of schistosoma mansoni.

    PubMed

    BUEDING, E

    1950-05-20

    1. Schistosoma mansoni utilizes in 1 hour an amount of glucose equivalent to one-sixth to one-fifth of its dry weight. Over 80 per cent of the metabolized glucose is converted to lactic acid by this organism. 2. The rates of glucose utilization and of lactic acid production by S. mansoni are the same under aerobic and under anaerobic conditions. 3. A high rate of lactic acid production and the absence of a postanaerobic increase in the oxygen uptake differentiate S. mansoni from most other parasitic helminths whose metabolism has been studied. 4. Arsenite and p-chloromercuric benzoate inhibit in low concentrations the oxygen uptake and the rate of glycolysis of S. mansoni. This inhibition is not prevented or reversed by an excess of glutathione or of thioglycollate. 5. Fluoride inhibits the removal of glucose and the production of lactic acid by S. mansoni to the same degree. 6. Low concentrations of quinacrine (atabrine) do not affect the respiration or the carbohydrate metabolism of the schistosomes. 7. The inhibitory effect of aldehydes on the metabolism of S. mansoni has been measured. Among this group of compounds dl-glyceraldehyde and o-nitrobenzaldehyde are the most effective inhibitors of glycolysis. 8. In a concentration of 2.6 x 10(-6)M (1:1,000,000) a cyanine dye inhibits almost completely the respiration of the schistosomes, but has no effect on their rate of glycolysis. The oxygen uptake of the worms is inhibited by fuadin to a greater degree than their rate of glycolysis. 2-methyl-1,4-napthoquinone is a much more effective inhibitor of glycolysis than of the respiration of S. mansoni. The latter compound interacts with plasma albumin and, therefore, its inhibitory action on the metabolism of the schistosomes is greatly reduced in human serum or plasma. 9. Evidence is discussed which indicates that, in contrast to glycolysis, respiratory metabolism is not essential for the survival of S. mansoni.

  8. Resistance to niclosamide in Oncomelania hupensis, the intermediate host of Schistosoma japonicum: should we be worried?

    PubMed

    Dai, Jian-Rong; Li, You-Zi; Wang, Wei; Xing, Yun-Tian; Qu, Guo-Li; Liang, You-Sheng

    2015-02-01

    As the currently only available molluscicide, niclosamide has been widely used for snail control for over 2 decades in China. There is therefore a concern about the emergence of niclosamide-resistant snail populations following repeated, extensive use of the chemical. The purpose of this study was to investigate the likelihood of niclosamide resistance in Oncomelania hupensis in China. Active adult O. hupensis snails derived from 20 counties of 10 schistosomiasis-endemic provinces of China, of 10 snails in each drug concentration, were immersed in solutions of 1, 0.5, 0.25, 0.125, 0.063, 0.032, 0.016 and 0.008 mg L-1 of a 50% wettable powder of niclosamide ethanolamine salt (WPN) for 24 and 48 h at 25 °C, and the median lethal concentration (LC50) was estimated. Then, the 24- and 48-h WPN LC50 values were compared with those determined in the same sampling sites in 2002. The results indicated that the 24- and 48-h WPN LC50 values for O. hupensis were not significantly different from those determined in 2002 (P = 0.202 and 0.796, respectively). It is concluded that the current sensitivity of O. hupensis to niclosamide has not changed after more than 2 decades of repeated, extensive application in the main endemic foci of China, and there is no evidence of resistance to niclosamide detected in O. hupensis.

  9. Bioactivity of miltefosine against aquatic stages of Schistosoma mansoni, Schistosoma haematobium and their snail hosts, supported by scanning electron microscopy.

    PubMed

    Eissa, Maha M; El Bardicy, Samia; Tadros, Menerva

    2011-05-11

    Miltefosine, which is the first oral drug licensed for the treatment of leishmaniasis, was recently reported to be a promising lead compound for the synthesis of novel antischistosomal derivatives with potent activity in vivo against different developmental stages of Schistosoma mansoni. In this paper an in vitro study was carried out to investigate whether it has a biocidal activity against the aquatic stages of Schistosoma mansoni and its snail intermediate host, Biomphalaria alexandrina , thus being also a molluscicide. Additionally, to see whether miltefosine can have a broad spectrum antischistosomal activity, a similar in vitro study was carried out on the adult stage of Schistosoma haematobium, the second major human species, its larval stages and snail intermediate host, Bulinus truncutes. This was checked by scanning electron microscopy. Miltefosine proved to have in vitro ovicidal, schistolarvicidal and lethal activity on adult worms of both Schistosoma species and has considerable molluscicidal activity on their snail hosts. Scanning electron microscopy revealed several morphological changes on the different stages of the parasite and on the soft body of the snail, which further strengthens the current evidence of miltefosine's activity. This is the first report of mollusicidal activity of miltefosine and its in vitro schistosomicidal activity against S.haematobium. This study highlights miltefosine not only as a potential promising lead compound for the synthesis of novel broad spectrum schistosomicidal derivatives, but also for molluscicidals.

  10. Efficient expression and purification of a protease from the common cold virus, human rhinovirus type 14

    NASA Astrophysics Data System (ADS)

    Leong, L. E.-C.; Walker, P. A.; Porter, A. G.

    1992-08-01

    The protease (3C pro) from human rhinovirus serotype-14 (HRV-14) has been cloned and efficiently expressed in E. coli. A straightforward single-step purification of the recombinant 3C pro has been achieved by fusing the protein to the car☐y-terminus of the glutathione-S-transferase from Schistosoma japonicum. Modifications made to the 5' end of the PCR fragment coding for the 3C pro have allowed the specific cleavage of the fusion protein using thrombin to yield mature 3C pro with the correct amino-terminal amino acid. This protease has been shown to be active when assayed using synthetic peptides corresponding to the natural cleavage recognition sequences within the polyprotein. Other substrates are being developed for this protease for possible use in the screening of inhibitors of 3C pro. Sufficient protease 3C pro has been purified for initial attempts at crystallization.

  11. Nif- Hup- mutants of Rhizobium japonicum.

    PubMed Central

    Moshiri, F; Stults, L; Novak, P; Maier, R J

    1983-01-01

    Two H2 uptake-negative (Hup-) Rhizobium japonicum mutants were obtained that also lacked symbiotic N2 fixation (acetylene reduction) activity. One of the mutants formed green nodules and was deficient in heme. Hydrogen oxidation activity in this mutant could be restored by the addition of heme plus ATP to crude extracts. Bacteroid extracts from the other mutant strain lacked hydrogenase activity and activity for both of the nitrogenase component proteins. Hup+ revertants of the mutant strains regained both H2 uptake ability and nitrogenase activity. Images PMID:6874648

  12. Cytotoxic phenylpropanoid glycosides from Cirsium japonicum.

    PubMed

    Shang, Dong-Li; Ma, Qin-Ge; Wei, Rong-Rui

    2016-12-01

    Three new phenylpropanoid glycosides 1-3, along with nine known phenylpropanoid glycosides 4-12, were isolated from the aerial parts of Cirsium japonicum. The structures of isolated compounds were elucidated by chemical and spectroscopic methods. Compounds 1, 3, 6, 8, and 11 showed moderate cytotoxicities against MCF-7, U87, HCT116, and A549 cell lines with IC50 values in the range of 1.35-11.32 μM. The known compounds 4-12 were obtained from this plant for the first time.

  13. Schistosome egg antigens elicit a proinflammatory response by trophoblast cells of the human placenta.

    PubMed

    McDonald, Emily A; Kurtis, Jonathan D; Acosta, Luz; Gundogan, Fusun; Sharma, Surendra; Pond-Tor, Sunthorn; Wu, Hai-Wei; Friedman, Jennifer F

    2013-03-01

    Schistosomiasis affects nearly 40 million women of reproductive age. Many of these women are infected while pregnant and lactating. Several studies have demonstrated transplacental trafficking of schistosome antigens; however, little is known regarding how these antigens affect the developing fetus and placenta. To evaluate the impact of schistosomiasis on trophoblasts of the human placenta, we isolated primary trophoblast cells from healthy placentas delivered at term. These trophoblasts were placed in culture and treated with Schistosoma japonicum soluble egg antigens (SEA) or plasma from S. japonicum-infected pregnant women. Outcomes measured included cytokine production and activation of signal transduction pathways. Treatment of primary human trophoblast cells with SEA resulted in upregulation of the proinflammatory cytokines interleukin 6 (IL-6) and IL-8 and the chemokine macrophage inflammatory protein 1α (MIP-1α). Cytokine production in response to SEA was dose dependent and reminiscent of production in response to other proinflammatory stimuli, such as Toll-like receptor 2 (TLR2) and TLR4 agonists. In addition, the signaling pathways extracellular signal-regulated kinase 1/2 (ERK1/2), Jun N-terminal protein kinase (JNK), p38, and NF-κB were all activated by SEA in primary trophoblasts. These effects appeared to be mediated through both carbohydrate and protein epitopes of SEA. Finally, primary trophoblasts cocultured with plasma from S. japonicum-infected pregnant women produced increased levels of IL-8 compared to trophoblasts cocultured with plasma from uninfected pregnant women. We report here a direct impact of SEA on primary human trophoblast cells, which are critical for many aspects of a healthy pregnancy. Our data indicate that schistosome antigens can activate proinflammatory responses in trophoblasts, which might compromise maternal-fetal health in pregnancies complicated by schistosomiasis.

  14. Citrate as a siderophore in Bradyrhizobium japonicum.

    PubMed Central

    Guerinot, M L; Meidl, E J; Plessner, O

    1990-01-01

    Under iron-limiting conditions, many bacteria secrete ferric iron-specific ligands, generically termed siderophores, to aid in the sequestering and transport of iron. One strain of the nitrogen-fixing soybean symbiont Bradyrhizobium japonicum, 61A152, was shown to produce a siderophore when 20 B. japonicum strains were screened with all six chemical assays commonly used to detect such production. Production by strain 61A152 was detected via the chrome azurol S assay, a general test for siderophores which is independent of siderophore structure. The iron-chelating compound was neither a catechol nor a hydroxamate and was ninhydrin negative. It was determined to be citric acid via a combination of thin-layer chromatography and high-voltage paper electrophoresis; this identification was verified by a specific enzymatic assay for citric acid. The inverse correlation which was observed between citric acid release and the iron content of the medium suggested that ferric citrate could serve as an iron source. This was confirmed via growth and transport assays. Exogenously added ferric citrate could be used to overcome iron starvation, and iron-deficient cells actively transported radiolabeled ferric citrate. These results, taken together, indicate a role for ferric citrate in the iron nutrition of this strain, which has been shown to be an efficient nitrogen-fixing strain on a variety of soybean cultivars. PMID:2140566

  15. Lactate as a Novel Quantitative Measure of Viability in Schistosoma mansoni Drug Sensitivity Assays

    PubMed Central

    Howe, Stephanie; Zöphel, Dorina; Subbaraman, Harini; Unger, Clemens; Held, Jana; Engleitner, Thomas; Hoffmann, Wolfgang H.

    2014-01-01

    Whole-organism compound sensitivity assays are a valuable strategy in infectious diseases to identify active molecules. In schistosomiasis drug discovery, larval-stage Schistosoma allows the use of a certain degree of automation in the screening of compounds. Unfortunately, the throughput is limited, as drug activity is determined by manual assessment of Schistosoma viability by microscopy. To develop a simple and quantifiable surrogate marker for viability, we targeted glucose metabolism, which is central to Schistosoma survival. Lactate is the end product of glycolysis in human Schistosoma stages and can be detected in the supernatant. We assessed lactate as a surrogate marker for viability in Schistosoma drug screening assays. We thoroughly investigated parameters of lactate measurement and performed drug sensitivity assays by applying schistosomula and adult worms to establish a proof of concept. Lactate levels clearly reflected the viability of schistosomula and correlated with schistosomulum numbers. Compounds with reported potencies were tested, and activities were determined by lactate assay and by microscopy. We conclude that lactate is a sensitive and simple surrogate marker to be measured to determine Schistosoma viability in compound screening assays. Low numbers of schistosomula and the commercial availability of lactate assay reagents make the assay particularly attractive to throughput approaches. Furthermore, standardization of procedures and quantitative evaluation of compound activities facilitate interassay comparisons of potencies and, thus, concerted drug discovery approaches. PMID:25487803

  16. Ethyl acetate extract of Hypericum japonicum induces apoptosis via the mitochondria-dependent pathway in vivo and in vitro.

    PubMed

    Zhuang, Qunchuan; Li, Jing; Chen, Youqin; Lin, Jiumao; Lai, Faze; Chen, Xuzheng; Lin, Xindeng; Peng, Jun

    2015-10-01

    The widely-used Chinese medicinal herb Hypericum japonicum, also known as Hypericum japonicum Thunb or Tianjihuang, displays potent anti‑carcinogenic effects against liver cancer. However, the molecular mechanism underlying the therapeutic effects of Hypericum japonicum remains to be elucidated. The present study investigated the in vivo efficacy of ethyl acetate extract of Hypericum japonicum (EAEHJ) against tumor growth in an H22 cell‑bearing liver cancer mouse model. Treatment with EAEHJ significantly reduced tumor weight, but had no effect on murine body weight. The results of the present study also showed that EAEHJ induced H22 cell apoptosis in vivo. In addition, the anti‑carcinogenic effects of EAEHJ were investigated in vitro. The results of the present study demonstrate that both phospholipid asymmetry in the plasma membrane and mitochondrial membrane potential were deregulated in HepG2 human hepatoma cells, following treatment with EAEHJ. Treatment with EAEHJ also increased the ratio of pro‑apoptotic B‑cell lymphoma 2 (Bcl‑2)‑associated X protein (Bax) to anti‑apoptotic Bcl‑2, and activated the caspase‑9 signaling pathway. These results suggest that EAEHJ is able to trigger the apoptosis of liver cancer cells via the mitochondria-dependent pathway.

  17. Ethyl acetate extract of Hypericum japonicum induces apoptosis via the mitochondria-dependent pathway in vivo and in vitro

    PubMed Central

    ZHUANG, QUNCHUAN; LI, JING; CHEN, YOUQIN; LIN, JIUMAO; LAI, FAZE; CHEN, XUZHENG; LIN, XINDENG; PENG, JUN

    2015-01-01

    The widely-used Chinese medicinal herb Hypericum japonicum, also known as Hypericum japonicum Thunb or Tianjihuang, displays potent anti-carcinogenic effects against liver cancer. However, the molecular mechanism underlying the therapeutic effects of Hypericum japonicum remains to be elucidated. The present study investigated the in vivo efficacy of ethyl acetate extract of Hypericum japonicum (EAEHJ) against tumor growth in an H22 cell-bearing liver cancer mouse model. Treatment with EAEHJ significantly reduced tumor weight, but had no effect on murine body weight. The results of the present study also showed that EAEHJ induced H22 cell apoptosis in vivo. In addition, the anti-carcinogenic effects of EAEHJ were investigated in vitro. The results of the present study demonstrate that both phospholipid asymmetry in the plasma membrane and mitochondrial membrane potential were deregulated in HepG2 human hepatoma cells, following treatment with EAEHJ. Treatment with EAEHJ also increased the ratio of pro-apoptotic B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) to anti-apoptotic Bcl-2, and activated the caspase-9 signaling pathway. These results suggest that EAEHJ is able to trigger the apoptosis of liver cancer cells via the mitochondria-dependent pathway. PMID:26239512

  18. NEDD8 conjugation in Schistosoma mansoni: genome analysis and expression profiles.

    PubMed

    Pereira, Roberta V; Gomes, Matheus de S; Olmo, Roenick P; Souza, Daniel M; Jannotti-Passos, Liana K; Baba, Elio H; Castro-Borges, William; Guerra-Sá, Renata

    2013-04-01

    NEDD8 is an ubiquitin-like molecule that covalently binds to target proteins through an enzymatic cascade analogous to ubiquitylation. This modifier is known to bind to p53 and p73, as well as all Cullin family proteins, which are essential components of Skp1/Cul-1/F-box protein (SCF)-like Ub ligase complexes. Here, we focused on a genomic analysis of the genes involved in the NEDD8 conjugation pathway in Schistosoma mansoni. The results revealed seven genes related to NEDD8 conjugation that are conserved in Schistosoma japonicum, Caenorhabditis elegans, Drosophila melanogaster and Homo sapiens. We performed quantitative RT-PCR (qRT-PCR), which showed differential profiles for Smnedd8, Smapp1, Smuba3, Smube2f, Smdcn1, Smrbx and Smsenp8 throughout the life cycle of S. mansoni. Upregulation was observed in 3-day-old schistosomula and adult worms for all analysed genes. We also analysed the transcription levels of Cullin family members Smp63 and Smp73, and observed upregulation in early schistosomula, while cercariae and adult worms showed expression levels similar to one another. Taken together, these results suggest that the NEDDylation/DeNEDDylation pathway controls important cellular regulators during worm development from cercariae to schistosomula and, finally, to adult.

  19. Toward Measuring Schistosoma Response to Praziquantel Treatment with Appropriate Descriptors of Egg Excretion

    PubMed Central

    Olliaro, Piero L.; Vaillant, Michel; Diawara, Aïssatou; Coulibaly, Jean T.; Garba, Amadou; Keiser, Jennifer; King, Charles H.; Knopp, Stefanie; Landouré, Aly; N’Goran, Eliézer K.; Raso, Giovanna; Scherrer, Alexandra U.; Sousa-Figueiredo, José Carlos; Stete, Katarina; Zhou, Xiao-Nong; Utzinger, Jürg

    2015-01-01

    Background The control of schistosomiasis emphasizes preventive chemotherapy with praziquantel, which aims at decreasing infection intensity and thus morbidity in individuals, as well as transmission in communities. Standardizing methods to assess treatment efficacy is important to compare trial outcomes across settings, and to monitor program effectiveness consistently. We compared customary methods and looked at possible complementary approaches in order to derive suggestions for standardizing outcome measures. Methodology/Principal Findings We analyzed data from 24 studies conducted at African, Asian, and Latin American sites, enrolling overall 4,740 individuals infected with Schistosoma mansoni, S. haematobium, or S. japonicum, and treated with praziquantel at doses of 40–80 mg/kg. We found that group-based arithmetic and geometric means can be used interchangeably to express egg reduction rates (ERR) only if treatment efficacy is high (>95%). For lower levels of efficacy, ERR estimates are higher with geometric than arithmetic means. Using the distribution of individual responses in egg excretion, 6.3%, 1.7% and 4.3% of the subjects treated for S. haematobium, S. japonicum and S. mansoni infection, respectively, had no reduction in their egg counts (ERR = 0). The 5th, 10th, and 25th centiles of the subjects treated for S. haematobium had individual ERRs of 0%, 49.3%, and 96.5%; the corresponding values for S. japonicum were 75%, 99%, and 99%; and for S. mansoni 18.2%, 65.3%, and 99.8%. Using a single rather than quadruplicate Kato-Katz thick smear excluded 19% of S. mansoni-infected individuals. Whilst the effect on estimating ERR was negligible by individual studies, ERR estimates by arithmetic means were 8% lower with a single measurement. Conclusions/Significance Arithmetic mean calculations of Schistosoma ERR are more sensitive and therefore more appropriate to monitor drug performance than geometric means. However, neither are satisfactory to identify

  20. Emerging complexity in the denitrification regulatory network of Bradyrhizobium japonicum.

    PubMed

    Torres, María J; Bueno, Emilio; Mesa, Socorro; Bedmar, Eulogio J; Delgado, María J

    2011-01-01

    Bradyrhizobium japonicum is a Gram-negative soil bacterium symbiotically associated with soya bean plants, which is also able to denitrify under free-living and symbiotic conditions. In B. japonicum, the napEDABC, nirK, norCBQD and nosRZDYFLX genes which encode reductases for nitrate, nitrite, nitric oxide and nitrous oxide respectively are required for denitrification. Similar to many other denitrifiers, expression of denitrification genes in B. japonicum requires both oxygen limitation and the presence of nitrate or a derived nitrogen oxide. In B. japonicum, a sophisticated regulatory network consisting of two linked regulatory cascades co-ordinates the expression of genes required for microaerobic respiration (the FixLJ/FixK2 cascade) and for nitrogen fixation (the RegSR/NifA cascade). The involvement of the FixLJ/FixK2 regulatory cascade in the microaerobic induction of the denitrification genes is well established. In addition, the FNR (fumarase and nitrate reduction regulator)/CRP(cAMP receptor protein)-type regulator NnrR expands the FixLJ/FixK2 regulatory cascade by an additional control level. A role for NifA is suggested in this process by recent experiments which have shown that it is required for full expression of denitrification genes in B. japonicum. The present review summarizes the current understanding of the regulatory network of denitrification in B. japonicum.

  1. Genetic diversity and population structure of Schistosoma mansoni within human infra-populations in Mwea, central Kenya assessed by microsatellite markers

    PubMed Central

    Agola, L. E.; Steinauer, M. L.; Mburu, D. N.; Mungai, B.N.; Mwangi, I.N.; Magoma, G.N.; Loker, E. S.; Mkoji, G. M.

    2009-01-01

    A recently developed high-throughput technique that allows multi-locus microsatellite analysis of individual miracidia of Schistosoma mansoni was used to assess the levels of genetic diversity and population structure in 12 infrapopulations of the parasite, each infrapopulation derived from an infected school child from the Mwea area, central Kenya. The mean number of alleles per locus was in the range 8.22 – 10.22, expected heterozygosity in Hardy-Weinberg equilibrium was 0.68 – 0.70, and pair wise FST values ranged from 0.16 −3.98% for the 12 infrapopulations. Although the genetic diversity within each infrapopulation of S. mansoni in this area was generally high, low levels of genetic structure were observed, suggestive of high levels of gene flow among infrapopulations. Private alleles were found in 8 of the 12 infrapopulation, the highest number of private alleles recorded per infrapopulation was 3. Our data suggest that the level of gene flow among infrapopulations of S. mansoni in Mwea is extremely high thus, providing opportunity for spread of rare alleles, including those that may confer character traits such as drug resistance and virulence. PMID:19427295

  2. Evidence for the presence of two (Ca(2+)-Mg2+) ATPases with different sensitivities to thapsigargin and cyclopiazonic acid in the human flatworm Schistosoma mansoni.

    PubMed

    Cunha, V M; Reis, J M; Noël, F

    1996-06-01

    The subcellular localization of the (Ca(2+)-Mg2+)ATPase activities present in heterogeneous (P1), nuclear (P2), mitochondrial (P3) and microsomal (P4) fractions obtained by differential centrifugation of Schistosoma mansoni homogenate was investigated. In the microsomal fraction (P4), the (Ca(2+)-Mg2+)ATPase activity was completely blocked by 3 microM thapsigargin, whereas in the more heterogeneous fraction (P1), about 20-30% of this activity was resistant to the drug. The same pattern of inhibition was observed using 20 microM cyclopiazonic acid. The distribution pattern of (Ca(2+)-Mg2+)ATPase activity among the four subcellular fractions (P1 > P4 > > P3 > P2) was completely different from that of [3H]-ouabain binding sites (P1 > or = P4 = P2 > or = P3). These results indicate that the (Ca(2+)-Mg2+)ATPase in S. mansoni is predominantly of the SERCA type (localized in the endoplasmic reticulum). However, there is another enzyme, present in lower proportion that could have a plasma membrane origin (PMCA type), because it is resistant to thapsigargin and cyclopiazonic acid and its inhibition by tamoxifen is antagonized by calmodulin.

  3. The immunologically reactive O-linked polysaccharide chains derived from circulating cathodic antigen isolated from the human blood fluke Schistosoma mansoni have Lewis x as repeating unit.

    PubMed

    Van Dam, G J; Bergwerff, A A; Thomas-Oates, J E; Rotmans, J P; Kamerling, J P; Vliegenthart, J F; Deelder, A M

    1994-10-01

    The gut-associated excretory antigen circulating cathodic antigen (CCA) was isolated by immunoaffinity chromatography from adult Schistosoma mansoni worms, which were collected from infected golden hamsters. This antigen is probably involved in protection of the schistosome gut and is increasingly used in highly sensitive and specific immunodiagnostic assays. Amino acid analysis before and after alkaline borohydride treatment of CCA and monosaccharide analysis indicated that CCA is O-glycosylated mostly via GalNAc-Thr. After reductive alkaline treatment, the O-linked carbohydrate chains were fractionated by gel-permeation chromatography, followed by normal-phase HPLC on LiChrosorb-NH2. Carbohydrate-positive fractions were investigated by one-dimensional and two-dimensional 1H-NMR spectroscopy, fast atom bombardment mass spectrometry and collision-induced-dissociation tandem mass spectrometry. The analyses showed that the low-molecular-mass O-linked oligosaccharide alditols (the minor fraction) consist of disaccharides to hexasaccharides having the Gal beta (1-3)GalNAc-OL core in common. The major carbohydrate fraction comprises a population of polysaccharides, containing Lewis x repeating units (-3)Gal beta (1-4)[Fuc alpha (1-3)]GlcNAc beta (1-). CCA-specific monoclonal antibodies and IgM antibodies in patient sera recognized the fucosylated O-linked carbohydrate antigenic structures. Since CCA evokes a strong IgM antibody response and carbohydrate structures containing repeating Lewis x units are found on circulating neutrophils, it is proposed that the antigenic poly-Lewis x polysaccharide of CCA is involved in the induction of auto-immunity against granulocytes, resulting in the mild to moderate neutropenia observed during schistosome infection.

  4. In Silico Analysis of the Fucosylation-Associated Genome of the Human Blood Fluke Schistosoma mansoni: Cloning and Characterization of the Fucosyltransferase Multigene Family

    PubMed Central

    Peterson, Nathan A.; Anderson, Tavis K.; Yoshino, Timothy P.

    2013-01-01

    Fucosylated glycans of the parasitic flatworm Schistosoma mansoni play key roles in its development and immunobiology. In the present study we used a genome-wide homology-based bioinformatics approach to search for genes that contribute to fucosylated glycan expression in S. mansoni, specifically the α2-, α3-, and α6-fucosyltransferases (FucTs), which transfer L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. We identified and in silico characterized several novel schistosome FucT homologs, including six α3-FucTs and six α6-FucTs, as well as two protein O-FucTs that catalyze the unrelated transfer of L-fucose to serine and threonine residues of epidermal growth factor- and thrombospondin-type repeats. No α2-FucTs were observed. Primary sequence analyses identified key conserved FucT motifs as well as characteristic transmembrane domains, consistent with their putative roles as fucosyltransferases. Most genes exhibit alternative splicing, with multiple transcript variants generated. A phylogenetic analysis demonstrated that schistosome α3- and α6-FucTs form monophyletic clades within their respective gene families, suggesting multiple gene duplications following the separation of the schistosome lineage from the main evolutionary tree. Quantitative decreases in steady-state transcript levels of some FucTs during early larval development suggest a possible mechanism for differential expression of fucosylated glycans in schistosomes. This study systematically identifies the complete repertoire of FucT homologs in S. mansoni and provides fundamental information regarding their genomic organization, genetic variation, developmental expression, and evolutionary history. PMID:23696810

  5. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the fucosyltransferase multigene family.

    PubMed

    Peterson, Nathan A; Anderson, Tavis K; Yoshino, Timothy P

    2013-01-01

    Fucosylated glycans of the parasitic flatworm Schistosoma mansoni play key roles in its development and immunobiology. In the present study we used a genome-wide homology-based bioinformatics approach to search for genes that contribute to fucosylated glycan expression in S. mansoni, specifically the α2-, α3-, and α6-fucosyltransferases (FucTs), which transfer L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. We identified and in silico characterized several novel schistosome FucT homologs, including six α3-FucTs and six α6-FucTs, as well as two protein O-FucTs that catalyze the unrelated transfer of L-fucose to serine and threonine residues of epidermal growth factor- and thrombospondin-type repeats. No α2-FucTs were observed. Primary sequence analyses identified key conserved FucT motifs as well as characteristic transmembrane domains, consistent with their putative roles as fucosyltransferases. Most genes exhibit alternative splicing, with multiple transcript variants generated. A phylogenetic analysis demonstrated that schistosome α3- and α6-FucTs form monophyletic clades within their respective gene families, suggesting multiple gene duplications following the separation of the schistosome lineage from the main evolutionary tree. Quantitative decreases in steady-state transcript levels of some FucTs during early larval development suggest a possible mechanism for differential expression of fucosylated glycans in schistosomes. This study systematically identifies the complete repertoire of FucT homologs in S. mansoni and provides fundamental information regarding their genomic organization, genetic variation, developmental expression, and evolutionary history.

  6. The binding of human low-density lipoproteins to the surface of schistosomula of Schistosoma mansoni is inhibited by polyanions and reduces the binding of anti-schistosomal antibodies.

    PubMed Central

    Chiang, C. P.; Caulfield, J. P.

    1989-01-01

    Host molecules such as serum lipoproteins, blood group glycolipids, and histocompatibility antigens may bind to schistosomes and thereby prevent immune recognition of the parasite. This study examines the kinetics of lipoprotein binding, the ability of polyanions to inhibit lipoprotein binding, the binding of anti-schistosomal antibodies to worms that have previously bound low-density lipoprotein (LDL), and the distribution of lipoproteins bound to the parasites. Lipoproteins in human serum (HS) and purified LDL, very low-density lipoprotein (VLDL), and apolipoprotein B (apo B) in defined media were demonstrated on the surface of schistosomula of Schistosoma mansoni by fluorescence and immunoelectron microscopy using a polyclonal goat anti-human apolipoprotein B antibody (anti-apo B). By fluorophotometric microscopy, lipoprotein binding began within 15 minutes and was largely completed within 3 hours of exposure. Lipoprotein binding saturated at 10% HS or 20 micrograms protein/300 microliters of purified LDL. Suramin inhibited LDL binding by 59% in a dose-dependent fashion. In the absence of LDL in the medium, 2 mM suramin dissociated 41% of bound LDL from the worm surface within 15 minutes and 10 mg/ml heparin dissociated 36%. The binding of human anti-schistosomal antibodies to schistosomula was inhibited by bound LDL. By fluorescence microscopy, serum or purified lipoproteins were distributed over the entire surface of the parasite with focal areas of high intensity. Ultrastructurally, reaction product was seen on the outer leaflet of the outer tegumental membrane and in aggregates and surrounding vesicular structures varying in diameter from 13 to 83 nm. These studies demonstrate that lipoproteins bind to the surface of schistosomula. The binding of lipoproteins is partially inhibited by polyanions, reduces the binding of human anti-schistosomal antibodies, and may help the parasite escape the immune response. Images Figure 1 Figure 9 Figure 10 PMID:2719071

  7. Multiplex real-time PCR monitoring of intestinal helminths in humans reveals widespread polyparasitism in Northern Samar, the Philippines.

    PubMed

    Gordon, Catherine A; McManus, Donald P; Acosta, Luz P; Olveda, Remigio M; Williams, Gail M; Ross, Allen G; Gray, Darren J; Gobert, Geoffrey N

    2015-06-01

    The global socioeconomic importance of helminth parasitic disease is underpinned by the considerable clinical impact on millions of people. While helminth polyparasitism is considered common in the Philippines, little has been done to survey its extent in endemic communities. High morphological similarity of eggs between related species complicates conventional microscopic diagnostic methods which are known to lack sensitivity, particularly in low intensity infections. Multiplex quantitative PCR diagnostic methods can provide rapid, simultaneous identification of multiple helminth species from a single stool sample. We describe a multiplex assay for the differentiation of Ascaris lumbricoides, Necator americanus, Ancylostoma, Taenia saginata and Taenia solium, building on our previously published findings for Schistosoma japonicum. Of 545 human faecal samples examined, 46.6% were positive for at least three different parasite species. High prevalences of S. japonicum (90.64%), A. lumbricoides (58.17%), T. saginata (42.57%) and A. duodenale (48.07%) were recorded. Neither T. solium nor N. americanus were found to be present. The utility of molecular diagnostic methods for monitoring helminth parasite prevalence provides new information on the extent of polyparasitism in the Philippines municipality of Palapag. These methods and findings have potential global implications for the monitoring of neglected tropical diseases and control measures. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  8. Sensitive and rapid detection of Paragonimus westermani infection in humans and animals by loop-mediated isothermal amplification (LAMP).

    PubMed

    Chen, M X; Ai, L; Zhang, R L; Xia, J J; Wang, K; Chen, S H; Zhang, Y N; Xu, M J; Li, X; Zhu, X Q; Chen, J X

    2011-05-01

    In the present study, a loop-mediated isothermal amplification (LAMP) assay was developed and validated for the detection of Paragonimus westermani adults, metacercariae, and eggs in human and animal samples. The LAMP amplification can be finished in 45 min under isothermal condition at 60°C by employing a set of four species-specific primer mixtures and the results can be checked by naked-eye visualization. No amplification products were detected with deoxyribunucleic acid (DNA) of related trematode species including Fasciola hepatica, Fasciola gigantica, Clonorchis sinensis, Opisthorchis viverrini, Schistosoma mansoni, and Schistosoma japonicum. The method was further validated by examining P. westermani DNA in intermediate hosts including freshwater crabs and crayfish, as well as in sputum and pleural fluid samples from patients of paragonimiasis. These results indicated that the LAMP assay was highly specific, sensitive, and rapid, and it was approximately 100 times more sensitive than conventional specific PCR. The LAMP assay established in this study provides a rapid and sensitive tool for the detection of P. westermani DNA in freshwater crabs, crayfish, sputum, and pleural fluid samples, which has important implications for effective control of human paragonimiasis.

  9. Detection of Schistosoma Antibodies and exploration of associated factors among local residents around Inlay Lake, Southern Shan State, Myanmar.

    PubMed

    Soe, Htin Zaw; Oo, Cho Cho; Myat, Tin Ohn; Maung, Nay Soe

    2017-03-01

    Schistosomiasis is a chronic parasitic disease caused by blood flukes (trematode worms) of the genus Schistosoma. Its transmission has been reported in 78 countries affecting at least 258 million people world-wide. It was documented that S. japonicum species was prevalent in Shan State, Myanmar, but the serological study was not conducted yet. General objective of the present study was to detect schistosoma antibodies and explore associated factors among local residents living around Inlay Lake, Nyaung Shwe Township, and Southern Shan State, Myanmar. An exploratory and cross-sectional analytic study was conducted among local residents (n = 315) in selected rural health center (RHC) areas from December 2012 through June 2013. The participants were interviewed with pretested semi-structured questionnaires and their blood samples (serum) were tested using Schistosomiasis Serology Microwell ELISA test kits (sensitivity 100% and specificity 85%) which detected IgG antibodies but could not distinguish between a new and past infection. Data collected were analysed by SPSS software 16.0 and associations of variables were determined by Chi-squared test with a significant level set at 0.05. Schistosoma seroprevalence (IgG) in study area was found to be 23.8% (95% CI: 18.8-28.8%). The present study is the first and foremost study producing serological evidence of schistosoma infection-one of the neglected tropical diseases-in local people of Myanmar. The factors significantly associated with seropositivity were being male [OR = 2.6 (95% CI: 1.5-4.49), P < 0.001], residence [OR = 3.41 (95% CI: 1.6-7.3), P < 0.05 for Khaung Daing vs. Min Chaung] and education levels [OR = 4.5 (95% CI: 1.18-17.16), P < 0.05 for illiterate/3Rs level vs. high/graduate and OR = 3.16 (95% CI: 1.26-7.93), P < 0.05 for primary/middle level vs. high/graduate] all factors classically associated with risk of schistosoma infection. None of the behavioural factors tested

  10. Making the most of mitochondrial genomes--markers for phylogeny, molecular ecology and barcodes in Schistosoma (Platyhelminthes: Digenea).

    PubMed

    Zarowiecki, M Z; Huyse, T; Littlewood, D T J

    2007-10-01

    designed against Schistosoma mekongi and Schistosoma malayensis were tested successfully against Schistosoma japonicum. In combination, these fragments encompass 20-27% of the variation amongst the genomes (average total length approximately 14,000bp), thus providing an efficient means of encapsulating the greatest amount of variation within the shortest sequence. Comparative mitogenomics provides the basis of a rational approach to molecular marker selection and optimisation.

  11. A link between arabinose utilization and oxalotrophy in Bradyrhizobium japonicum.

    PubMed

    Koch, Marion; Delmotte, Nathanaël; Ahrens, Christian H; Omasits, Ulrich; Schneider, Kathrin; Danza, Francesco; Padhi, Barnali; Murset, Valérie; Braissant, Olivier; Vorholt, Julia A; Hennecke, Hauke; Pessi, Gabriella

    2014-04-01

    Rhizobia have a versatile catabolism that allows them to compete successfully with other microorganisms for nutrients in the soil and in the rhizosphere of their respective host plants. In this study, Bradyrhizobium japonicum USDA 110 was found to be able to utilize oxalate as the sole carbon source. A proteome analysis of cells grown in minimal medium containing arabinose suggested that oxalate oxidation extends the arabinose degradation branch via glycolaldehyde. A mutant of the key pathway genes oxc (for oxalyl-coenzyme A decarboxylase) and frc (for formyl-coenzyme A transferase) was constructed and shown to be (i) impaired in growth on arabinose and (ii) unable to grow on oxalate. Oxalate was detected in roots and, at elevated levels, in root nodules of four different B. japonicum host plants. Mixed-inoculation experiments with wild-type and oxc-frc mutant cells revealed that oxalotrophy might be a beneficial trait of B. japonicum at some stage during legume root nodule colonization.

  12. Antigenic Analysis of Rhizobium japonicum by Immunodiffusion

    PubMed Central

    Dudman, W. F.

    1971-01-01

    Immunodiffusion reactions were studied with seven strains of Rhizobium japonicum and three strains of the cowpea miscellany by using antisera against eight of the strains. Most strains yielded only weak precipitin bands when untreated cell suspensions were used as antigens in the diffusions. Ultrasonic disruption or heat treatment of the cells led to stronger bands, and immersion in boiling water for 20 min was used as the standard procedure for preparing these bacteria for immunodiffusion analysis. Heat-labile antigens were detected in only a few strains; the major antigens of all of the strains appeared to be heat-stable. Many of the strains cross-reacted, sometimes in a nonreciprocal manner; unheated cell suspensions cross-reacted more widely but more weakly than the heated suspensions. Heat-treated crushed nodule preparations reacted well in immunodiffusions. The antigens of cultured cell and nodule extract (bacteroid) forms of three strains were compared. In one of these strains, an antigen present in the cultured cells was absent from the bacteroids. Unknown strains present in soybean root nodules were readily identified by immunodiffusion. Images PMID:4998353

  13. Molybdate transport by Bradyrhizobium japonicum bacteroids.

    PubMed

    Maier, R J; Graham, L

    1988-12-01

    Bacteroid suspensions of Bradyrhizobium japonicum USDA 136 isolated from soybeans grown in Mo-deficient conditions were able to transport molybdate at a nearly constant rate for up to 1 min. The apparent Km for molybdate was 0.1 microM, and the Vmax was about 5 pmol/min per mg (dry weight) of bacteroid. Supplementation of bacteroid suspensions with oxidizable carbon sources did not markedly increase molybdate uptake rates. Anaerobically isolated bacteroids accumulated twice as much Mo in 1 h as aerobically isolated cells did, but the first 5 min of molybdate uptake was not dependent on the isolation condition with respect to O2. Respiratory inhibitors such as cyanide, azide, and hydroxylamine did not appreciably affect molybdate uptake, even at concentrations that inhibited O2 uptake. The uncouplers carbonyl cyanide m-chlorophenylhydrazone (CCCP) and carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP) and the ionophores nigericin and monensin significantly inhibited molybdate uptake. The electrogenic ionophores valinomycin and gramicidin stimulated molybdate uptake. Rapid pH shift experiments indicated that molybdate transport depends on a transmembrane proton gradient (delta pH), and it is probably transported electroneutrally as H2MoO4. Most of the 99MoO4(2-) taken up was not exchangeable with a 100-fold excess of unlabeled MoO4(2-). Tungstate was a competitive inhibitor of molybdate uptake, with a Ki of 0.034 microM, and vanadate inhibited molybdate uptake slightly.

  14. Rapid competitive enzyme-linked immunosorbent assay using a monoclonal antibody reacting with a 15-kilodalton tegumental antigen of Schistosoma mansoni for serodiagnosis of schistosomiasis.

    PubMed Central

    Da Silva, A J; Piuvezam, M R; de Moura, H; Maddison, S; Peralta, J M

    1993-01-01

    A competitive enzyme-linked immunosorbent assay (CELISA) for antibody detection was developed by using a monoclonal antibody which reacts with a 15-kDa tegumental antigen of the adult worm of Schistosoma mansoni. This monoclonal antibody was not able to react with antigens of Schistosoma japonicum or Schistosoma haematobium in enzyme-linked immunoelectrotransfer blot (EITB) and indirect immunofluorescence tests. The assay was performed in a period of 1 h using an adult worm crude extract antigen. To evaluate the CELISA, a total of 73 serum samples was analyzed: 35 were from S. mansoni-infected patients, 23 were from individuals with parasitic infections other than schistosomiasis, and 14 were from healthy individuals. All serum samples from healthy individuals and from patients infected with other parasites were negative, as were two (6%) samples from patients infected with S. mansoni. EITB analysis showed that 32 of 33 CELISA-positive samples were positive in the EITB but with different patterns of reactivity. A 15-kDa protein reacted with 60% of serum samples, and a 60-kDa protein showed the highest level of reactivity (85%). The two samples from patients infected with S. mansoni that were negative in the CELISA reacted with 70-, 60-, 50-, 47-, and 38-kDa proteins. One sample, positive in CELISA, did not react with proteins of the antigenic extract. Images PMID:8408548

  15. Schistosoma haematobium infection in pregnancy.

    PubMed

    Siegrist, D; Siegrist-Obimpeh, P

    1992-04-01

    Due to the economical lack of safe drugs in a remote area of Ghana (Bawku District) to treat Schistosoma haematobium infection during pregnancy, the spontaneous outcome of the pregnancy in women with proved S. haematobium infection was compared with a control group (average hospital delivery). In a survey of 200 pregnant women, we found a prevalence of S. haematobium of 4.5%. From the original collection of 41 infected pregnant women we could follow 23 up to delivery. This group showed a higher number of preterm (less than 37 weeks) deliveries, 34.8% vs. 23.8% in the control group. The birthweights in term deliveries (greater than 37 weeks) were not significantly different (3012 g vs. 3103 g). In the preterm deliveries the birthweight was significantly lower in the infected group (1768 g vs. 2457 g, p less than 0.005).

  16. Response of soybean to seed inoculation with Bradyrhizobium japonicum and with mixed inoculants of B. japonicum and Azotobacter chroococcum.

    PubMed

    Kozieł, Monika; Gebala, Barbara; Martyniuk, Stefan

    2013-01-01

    Effects of pre-sowing soybean seed inoculation with Bradyrhizobium japonicum alone or with mixed inoculants containing soybean rhizobia and Azotobacter chroococcum were compared. In the pot experiment all the tested strains of soybean rhizobia in pure cultures or in mixtures with A. chroococcum significantly improved nodulation of soybean plants and seed yields of this crop. In micro-plot experiments pre-sowing soybean seeds treatment with the inoculant containing the most effective strain 94P of B. japonicum alone or with the mixed inoculant of strain 94P and A. chroococcum were equally effective in improving nodulation intensity and seed yields of soybean in comparison to the uninoculated soybean.

  17. RNA interference targeting leucine aminopeptidase blocks hatching of Schistosoma mansoni eggs.

    PubMed

    Rinaldi, Gabriel; Morales, Maria E; Alrefaei, Yousef N; Cancela, Martín; Castillo, Estela; Dalton, John P; Tort, José F; Brindley, Paul J

    2009-10-01

    Schistosoma mansoni leucine aminopeptidase (LAP) is thought to play a central role in hatching of the miracidium from the schistosome egg. We identified two discrete LAPs genes in the S. mansoni genome, and their orthologs in S. japonicum. The similarities in sequence and exon/intron structure of the two genes, LAP1 and LAP2, suggest that they arose by gene duplication and that this occurred before separation of the mansoni and japonicum lineages. The SmLAP1 and SmLAP2 genes have different expression patterns in diverse stages of the cycle; whereas both are equally expressed in the blood dwelling stages (schistosomules and adult), SmLAP2 expression was higher in free living larval (miracidia) and in parasitic intra-snail (sporocysts) stages. We investigated the role of each enzyme in hatching of schistosome eggs and the early stages of schistosome development by RNA interference (RNAi). Using RNAi, we observed marked and specific reduction of mRNAs, along with a loss of exopeptidase activity in soluble parasite extracts against the diagnostic substrate l-leucine-7-amido-4-methylcoumarin hydroxide. Strikingly, knockdown of either SmLAP1 or SmLAP2, or both together, was accompanied by >or=80% inhibition of hatching of schistosome eggs showing that both enzymes are important to the escape of miracidia from the egg. The methods employed here refine the utility of RNAi for functional genomics studies in helminth parasites and confirm these can be used to identify potential drug targets, in this case schistosome aminopeptidases.

  18. Brain schistosomiasis in mice experimentally infected with Schistosoma mansoni.

    PubMed

    Lambertucci, José Roberto; Fidelis, Thiago André; Pereira, Thiago Almeida; Coelho, Paulo Marcos Zech; Araujo, Neuza; Souza, Márcia Maria de; Brasileiro Filho, Geraldo; Pereira, Fausto Edmundo Lima; Antunes, Carlos Mauricio

    2014-01-01

    Human neuroschistosomiasis has been reported in the literature, but the possibility of modeling neuroschistosomiasis in mice is controversial. In two research laboratories in Brazil that maintain the Schistosoma mansoni life cycle in rodents, two mice developed signs of brain disease (hemiplegia and spinning), and both were autopsied. S. mansoni eggs, both with and without granuloma formation, were observed in the brain and meninges of both mice by optical microscopy. This is the first description of eggs in the brains of symptomatic mice that were experimentally infected with S. mansoni. An investigation of experimental neuroschistosomiasis is now feasible.

  19. Helminth Genomics: The Implications for Human Health

    PubMed Central

    Brindley, Paul J.; Mitreva, Makedonka; Ghedin, Elodie; Lustigman, Sara

    2009-01-01

    More than two billion people (one-third of humanity) are infected with parasitic roundworms or flatworms, collectively known as helminth parasites. These infections cause diseases that are responsible for enormous levels of morbidity and mortality, delays in the physical development of children, loss of productivity among the workforce, and maintenance of poverty. Genomes of the major helminth species that affect humans, and many others of agricultural and veterinary significance, are now the subject of intensive genome sequencing and annotation. Draft genome sequences of the filarial worm Brugia malayi and two of the human schistosomes, Schistosoma japonicum and S. mansoni, are now available, among others. These genome data will provide the basis for a comprehensive understanding of the molecular mechanisms involved in helminth nutrition and metabolism, host-dependent development and maturation, immune evasion, and evolution. They are likely also to predict new potential vaccine candidates and drug targets. In this review, we present an overview of these efforts and emphasize the potential impact and importance of these new findings. PMID:19855829

  20. [Observation on the change of anti-S. japonicum antibody level in population migrated from outside embankment to new town].

    PubMed

    Wen, Li-Yong; Lu, Shao-Hong; Chen, Jun-Hu; Zhang, Jian-Feng; Yu, Li-Ling; Ding, Jian-Zu; Yan, Xiao-Lan; Shen, Li-Ying; Zheng, Wei; Gao, Lu-Lu; Wang, Tian-Ping; Zhang, Shi-Qing; Chen, Geng-Xin; Ye, Yun; Zhou, Xiao-Nong; Zheng, Jiang

    2007-04-30

    To detect the change of the anti-S. japonicum antibody level after people migrated from outside embankment to newly established town. Three pilot spots were established for the investigation: one spot that both inhabitancy and cultivation disuse (A), one spot that only inhabitancy disuse but farming continued (B) and the third one served as control (C). DIGFA and ELISA were used to detect the antibody level in the populations from 2002 to 2005. The positive rate of anti-S. japonicum antibody declined significantly from 6.63% to 3.52% by DIGFA and from 7.26% to 3.71% by ELISA at spot A (chi2=5.2625, P<0.05; chi2=6.3296, P<0.05, respectively). There was no significant difference on the positive rate of antibody in spots B and C. The average A450 value of ELISA in the three spots was statistically analyzed by One-Way ANOVA. It was only in spot B that the average A450 value declined from 0.182 in 2003 to 0.147 in 2005 (P<0.01). The anti-S. japonicum antibody level in human population has decreased at certain degree after they migrated from outside embankment to new town.

  1. Inoculation with Bradyrhizobium japonicum enhances the organic and fatty acids content of soybean (Glycine max (L.) Merrill) seeds.

    PubMed

    Silva, Luís R; Pereira, Maria J; Azevedo, Jessica; Mulas, Rebeca; Velazquez, Encarna; González-Andrés, Fernando; Valentão, Patrícia; Andrade, Paula B

    2013-12-15

    Soybean (Glycine max (L.) Merrill) is one of the most important food crops for human and animal consumption, providing oil and protein at relatively low cost. The least expensive source of nitrogen for soybean is the biological fixation of atmospheric nitrogen by the symbiotic association with soil bacteria, belonging mainly to the genus Bradyrhizobium. This study was conducted to assess the effect of the inoculation of G. max with Bradyrhizobium japonicum on the metabolite profile and antioxidant potential of its seeds. Phenolic compounds, sterols, triterpenes, organic acids, fatty acids and volatiles profiles were characterised by different chromatographic techniques. The antioxidant activity was evaluated against DPPH, superoxide and nitric oxide radicals. Inoculation with B. japonicum induced changes in the profiles of primary and secondary metabolites of G. max seeds, without affecting their antioxidant capacity. The increase of organic and fatty acids and volatiles suggest a positive effect of the inoculation process. These findings indicate that the inoculation with nodulating B. japonicum is a beneficial agricultural practice, increasing the content of bioactive metabolites in G. max seeds owing to the establishment of symbiosis between plant and microorganism, with direct effects on seed quality.

  2. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import

    PubMed Central

    2013-01-01

    Background Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. Methods A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. Results We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous

  3. In silico analysis of the fucosylation-associated genome of the human blood fluke Schistosoma mansoni: cloning and characterization of the enzymes involved in GDP-L-fucose synthesis and Golgi import.

    PubMed

    Peterson, Nathan A; Anderson, Tavis K; Wu, Xiao-Jun; Yoshino, Timothy P

    2013-07-09

    Carbohydrate structures of surface-expressed and secreted/excreted glycoconjugates of the human blood fluke Schistosoma mansoni are key determinants that mediate host-parasite interactions in both snail and mammalian hosts. Fucose is a major constituent of these immunologically important glycans, and recent studies have sought to characterize fucosylation-associated enzymes, including the Golgi-localized fucosyltransferases that catalyze the transfer of L-fucose from a GDP-L-fucose donor to an oligosaccharide acceptor. Importantly, GDP-L-fucose is the only nucleotide-sugar donor used by fucosyltransferases and its availability represents a bottleneck in fucosyl-glycotope expression. A homology-based genome-wide bioinformatics approach was used to identify and molecularly characterize the enzymes that contribute to GDP-L-fucose synthesis and Golgi import in S. mansoni. Putative functions were further investigated through molecular phylogenetic and immunocytochemical analyses. We identified homologs of GDP-D-mannose-4,6-dehydratase (GMD) and GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase (GMER), which constitute a de novo pathway for GDP-L-fucose synthesis, in addition to a GDP-L-fucose transporter (GFT) that putatively imports cytosolic GDP-L-fucose into the Golgi. In silico primary sequence analyses identified characteristic Rossman loop and short-chain dehydrogenase/reductase motifs in GMD and GMER as well as 10 transmembrane domains in GFT. All genes are alternatively spliced, generating variants of unknown function. Observed quantitative differences in steady-state transcript levels between miracidia and primary sporocysts may contribute to differential glycotope expression in early larval development. Additionally, analyses of protein expression suggest the occurrence of cytosolic GMD and GMER in the ciliated epidermal plates and tegument of miracidia and primary sporocysts, respectively, which is consistent with previous localization of highly

  4. [Historical aspects of the risk factors of Schistosoma intercalatum schistosomiasis].

    PubMed

    Jusot, J F; Simarro, P; De Muynck, A

    1996-01-01

    Bilharziosis is a considerable public health problem. It is caused by many species of schistosoma, four of which have wide geographical distribution: Schistosoma mansoni, S. haematobium, S. japonicum and S. intercalatum. The recently discovered S. intercalatum is limited to central and west Africa. Its spread is progressive and its pathogenicity is not completely known. S. intercalatum bilharziosis is usually manifested in the form of dysentery. The physiopathologic explanation of this clinical manifestation is less clear. Immunopathologically, the formation of an inflammatory granuloma constitutes the origin of its symptoms. This is due to many biological factors including delayed hypersensitivity reactions. All cellular immunity changes will facilitate the appearance of symptoms. Our aim has been to show the importance of malnutrition as a pathogenic factor of S. intercalatum bilharziosis. The initial research hypothesis was as follows: malnutrition plays a role in the evolution of a patient from an asymptomatic state of infection to a symptomatic state of illness. We carried out the study in the suburbs of Bata, in Equatorial Guinea. The inhabitants of Ncolombong, essentially rural immigrants, comprised our study population. Following their consent, we recruited individuals less than 45 years of age who had not taken praziquantel during the last 12 months. We included a total of 297 patients. Our study was a case-control, matching on sex and age. A case was defined as an infected patient with acute or chronic diarrhea occurring within the last month' preceding the stool sample analysis. All cases were retained after exhaustive screening of the study population. Each case (group 1) was matched with one or several asymptomatic infected patients (group 2) and two or several asymptomatic noninfected patients chosen at random (group 3). The definition of malnutrition was as follows: weight/height < or = 90% for children less than 15 years of age or weight/height < or

  5. A review of schistosomiasis in immigrants in Western Australia, demonstrating the unusual longevity of Schistosoma mansoni.

    PubMed

    Harris, A R; Russell, R J; Charters, A D

    1984-01-01

    Sixteen patients with imported schistosomiasis in Western Australia, a non-endemic area, are recorded. Ten with Schistosoma mansoni had lived there for over 20 years, three for over 31 years and two for more than 32 years. No record of a life span of 31 years for S. mansoni can be found in the literature. The principal symptomatology in three patients with S. mansoni was hypersplenism. Four patients with S. mansoni were asymptomatic. Ten had eosinophil counts greater than 0.3 X 10(9)/1 and one who showed no peripheral eosinophilia had numerous eosinophil myelocytes in his bone marrow. A diagnosis of schistosomiasis was initially suspected in five cases by respective discovery of eosinophil myelocytes in the bone marrow, radiological evidence of calcification of the bladder wall and beading of both ureters, cytoscopic findings of sandy patches in the bladder, discovery of ova in the wall of a fallopian tube at ectopic gestation and the presence of ova and an adult worm in a uterine leiomyoma. The risk of infection of the Ord River Dam is greater for S. japonicum than for the African species. An epidemiological feature of this series is that refugees from Poland contracted schistosomiasis (S. mansoni) in refugee camps in East Africa and then migrated to Western Australia between 1950 and 1953.

  6. Tracking the fate of iron in early development of human blood flukes

    PubMed Central

    Jones, Malcolm K.; McManus, Donald P.; Sivadorai, Padma; Glanfield, Amber; Moertel, Luke; Belli, Sabina I.; Gobert, Geoffrey N.

    2007-01-01

    Iron (Fe) is an important trace element found in nearly all organisms, and is used as a cofactor in many biological reactions. One role for Fe in some invertebrates is in stabilization of extracellular matrices. The human blood fluke, Schistosoma japonicum, is responsible for significant human disease in developing and tropical nations. Disease in humans arises from host immunological reaction to parasite eggs that lodge in tissues. Schistosomes require Fe for development in their hosts, and store abundant Fe in vitelline (eggshell-forming) cells of the female system. The understanding of Fe metabolism and functionality are aspects of its biology that may be exploited in future therapeutics. The biology of Fe stores in vitelline cells of S. japonicum was investigated to illuminate possible functions of this element in early development of these parasites. Vitelline Fe is stored in yolk ferritin that is upregulated in females and is also expressed at low levels in egg-stages and adult males. Laser microdissection microscopy, coupled with reverse transcriptase- and real time-PCR amplification of schistosome ferritin sequences, confirmed that the vitelline cells are the likely progenitor cells of yolk ferritin. Assessment of Fe concentrations in whole male and whole female adult worms, eggs and purified eggshells by colorimetric assays and mass spectroscopy demonstrated higher levels of Fe in the female parasite, but also high levels of the element in whole parasite eggs and purified eggshell. Qualitative energy dispersive spectroscopy of purified eggshells, revealed that Fe is abundant in the eggshell, the matrix of which is composed of heavily cross-linked eggshell precursor proteins. Thus, vitelline stores of Fe are implicated in eggshell cross-linking in platyhelminths. These observations emphasise the importance of Fe in schistosome metabolism and egg formation and suggest new avenues for disruption of egg formation in these pathogenic parasites. PMID:17556009

  7. Tracking the fate of iron in early development of human blood flukes.

    PubMed

    Jones, Malcolm K; McManus, Donald P; Sivadorai, Padma; Glanfield, Amber; Moertel, Luke; Belli, Sabina I; Gobert, Geoffrey N

    2007-01-01

    Iron (Fe) is an important trace element found in nearly all organisms, and is used as a cofactor in many biological reactions. One role for Fe in some invertebrates is in stabilization of extracellular matrices. The human blood fluke, Schistosoma japonicum, is responsible for significant human disease in developing and tropical nations. Disease in humans arises from host immunological reaction to parasite eggs that lodge in tissues. Schistosomes require Fe for development in their hosts, and store abundant Fe in vitelline (eggshell-forming) cells of the female system. The understanding of Fe metabolism and functionality are aspects of its biology that may be exploited in future therapeutics. The biology of Fe stores in vitelline cells of S. japonicum was investigated to illuminate possible functions of this element in early development of these parasites. Vitelline Fe is stored in yolk ferritin that is upregulated in females and is also expressed at low levels in egg-stages and adult males. Laser microdissection microscopy, coupled with reverse transcriptase- and real time-PCR amplification of schistosome ferritin sequences, confirmed that the vitelline cells are the likely progenitor cells of yolk ferritin. Assessment of Fe concentrations in whole male and whole female adult worms, eggs and purified eggshells by colorimetric assays and mass spectroscopy demonstrated higher levels of Fe in the female parasite, but also high levels of the element in whole parasite eggs and purified eggshell. Qualitative energy dispersive spectroscopy of purified eggshells, revealed that Fe is abundant in the eggshell, the matrix of which is composed of heavily cross-linked eggshell precursor proteins. Thus, vitelline stores of Fe are implicated in eggshell cross-linking in platyhelminths. These observations emphasise the importance of Fe in schistosome metabolism and egg formation and suggest new avenues for disruption of egg formation in these pathogenic parasites.

  8. Improved Method of Typing Bradyrhizobium japonicum in Soybean Nodules

    PubMed Central

    Lieberman, Mark Tony; Zablotowicz, Robert M.; Davis-Omholt, Naida P.

    1986-01-01

    An improved method for antibiotic resistance recovery of Bradyrhizobium japonicum from soybean (Glycine max (L.) Merr.) nodules that is simple, time saving, and economical was developed. This technique involves the use of two 96-well microtiter plates as a multinodule sterilization chamber and a template and a third plate as a 16-point replicator constructed with steel nails affixed to the plate with epoxy cement. With this system a team of four technicians could type 3,000 nodules per day. This method was useful in assessing strain establishment and interstrain competition when one or more uniquely labeled strains of B. japonicum were inoculated onto either growth-room- or field-grown soybeans. Contamination was low and reproducibility across replicates approached the theoretical upper limit. Simplicity in design and use made this recovery method especially adaptable for field studies in which large numbers of nodules were required to provide a representative statistical sample offering good precision. Images PMID:16347035

  9. Two New Bioactive α-Pyrones from Hypericum japonicum.

    PubMed

    Hu, Linzhen; Wang, Zhenzhen; Zhang, Jinwen; Lu, Yuanyuan; Wang, Kaiping; Xue, Yongbo; Zhang, Yu; Zhang, Yonghui

    2016-04-19

    Hypericum japonicum (Guttiferae), a type of annual or perennial herb, has been historically applied to cure infectious hepatitis, acute and chronic hepatitis, gastrointestinal disorder, and internal hemorrhage. In our successive studies on the genus Hypericum, two new α-pyrones termed japopyrones A and B (1 and 2) were isolated from H. japonicum. Their structures and absolute configurations were established by the comprehensive analyses of spectroscopic data, the application of the Single-crystal X-ray diffraction structural analysis, and the experimental electronic circular dichroism (ECD) spectra. Bioactivity screenings suggested that compound 2 possessed the potential inhibition efficacy on lytic replication of Kaposi's sarcoma associated herpesvirus (KSHV) with an IC50 29.46 μM and a selective index of higher than 6.79, respectively.

  10. Evaluation of nitrate reductase activity in Rhizobium japonicum

    SciTech Connect

    Streeter, J.G.; DeVine, P.J.

    1983-08-01

    Nitrate reductase activity was evaluated by four approaches, using four strains of Rhizobium japonicum and 11 chlorate-resistant mutants of the four strains. It was concluded that in vitro assays with bacteria or bacteroids provide the most simple and reliable assessment of the presence or absence of nitrate reductase. Nitrite reductase activity with methyl viologen and dithionite was found, but the enzyme activity does not confound the assay of nitrate reductase. 18 references

  11. Ocular pathological changes in hamsters experimentally infected with Schistosoma mansoni.

    PubMed

    Ismail, H I H; Ashour, D S; Abou Rayia, D M; Ali, A L

    2016-11-01

    Ocular lesions have been reported in patients with schistosomiasis; however, the problem with studying schistosomal infection of the human eye is that biopsies are almost impossible to take, and histopathological examination of suspicious lesions can only be undertaken post-mortem or after enucleation. This work aimed to study the possible effects and pathogenesis of schistosomiasis on the eye. This study involved 55 hamsters; five hamsters remained non-infected and the remaining 50 hamsters were infected with Schistosoma mansoni cercariae. Infected hamsters were sacrificed on weeks 8, 12, 16 and 20 post-infection (pi). Eye sections were prepared and stained for histopathological and immunohistochemical studies. Histopathological changes detected in hamsters infected after 16 and 20 weeks included looseness and oedema of the innermost retinal layers together with hyperplastic polypoid growth. Neither eggs nor granulomata were detected in eye sections throughout the experimental period. Deposition of S. mansoni antigen was revealed in 35% of infected hamsters. Later, on weeks 16 and 20 pi, moderate subepithelial conjuctival deposits and marked subchoroidal and scleral deposition were detected. In conclusion, the deposition of schistosomal antigen and immune complexes may play a pivotal role in the ocular changes that occur in schistosomiasis, even in the absence of detectable Schistosoma eggs. Schistosomiasis should be suspected in cases with unexplained ophthalmological findings, especially in endemic areas.

  12. Stability of Bradyrhizobium japonicum Inoculants after Introduction into Soil

    PubMed Central

    Brunel, Brigitte; Cleyet-Marel, Jean-Claude; Normand, Philippe; Bardin, Rene

    1988-01-01

    Bradyrhizobium japonicum USDA 125-Sp, USDA 138, and USDA 138-Sm had been used as inoculants for soybean (Glycine max (L.) Merr.) in soils previously free of B. japonicum. At 8 to 13 years after their release, these strains were reisolated from soil samples. A total of 115 isolates were obtained through nodules, and seven colonies were obtained directly by a serological method. The stability of the inoculants was confirmed by comparing the reisolated cultures with their respective parental strains which had been preserved by being lyophilized or stored on a yeast extract-mannitol agar slant at 4°C. Comparisons were made on morphological and serological characters, carbon compound utilization (8 tested), intrinsic antibiotic resistance (9 tested), and enzymatic activity (19 tested). Mucous and nonmucous isolates of serogroup 125 were analyzed for symbiotic effectiveness and restriction fragment hybridization with a DNA probe. Our data suggest that the B. japonicum inoculants have survived for up to 13 years in the soils without significant mutation except for two reisolates with a slightly increased kanamycin resistance level. Images PMID:16347768

  13. Effects of culture age on symbiotic infectivity of Rhizobium japonicum

    SciTech Connect

    Bhuvaneswari, T.V.; Mills, K.K.; Crist, D.K.; Evans, W.R.; Bauer, W.D.

    1983-01-01

    The infectivity of the soybean symbiont Rhizobium japonicum changed two- to fivefold with culture age for strains 110 ARS, 138 Str Spc, and 123 Spc, whereas culture age had relatively little effect on the infectivity of strains 83 Str and 61A76 Str. Infectivity was measured by determining the number of nodules which developed on soybean primary roots in the zone which contained developing and preemergent root hairs at the time of inoculation. Root cells in this region of the host root are susceptible to Rhizobium infection, but this susceptibility is lost during acropetal development and maturation of the root cells within a period of 4 to 6 h. Profiles of nodulation frequency at different locations on the root were not affected by the age of the R. japonicum cultures, indicating that culture age affected the efficiency of Rhizobium infection rather than how soon infections were initiated after inoculation. Inoculum dose-response experiments also indicated that culture age affected the efficiency of infection. Two strains, 61A76 Str and 83 Str, were relatively inefficient at all culture ages, particularly at low inoculum doses. Changes in infectivity with culture age were reasonably well correlated with changes in the proportion of cells in a culture capable of binding soybean lectin. Suspensions of R. japonicum in water were found to retain their viability and infectivity. 15 references, 6 figures, 2 tables.

  14. A Link between Arabinose Utilization and Oxalotrophy in Bradyrhizobium japonicum

    PubMed Central

    Koch, Marion; Delmotte, Nathanaël; Ahrens, Christian H.; Omasits, Ulrich; Schneider, Kathrin; Danza, Francesco; Padhi, Barnali; Murset, Valérie; Braissant, Olivier; Vorholt, Julia A.; Hennecke, Hauke

    2014-01-01

    Rhizobia have a versatile catabolism that allows them to compete successfully with other microorganisms for nutrients in the soil and in the rhizosphere of their respective host plants. In this study, Bradyrhizobium japonicum USDA 110 was found to be able to utilize oxalate as the sole carbon source. A proteome analysis of cells grown in minimal medium containing arabinose suggested that oxalate oxidation extends the arabinose degradation branch via glycolaldehyde. A mutant of the key pathway genes oxc (for oxalyl-coenzyme A decarboxylase) and frc (for formyl-coenzyme A transferase) was constructed and shown to be (i) impaired in growth on arabinose and (ii) unable to grow on oxalate. Oxalate was detected in roots and, at elevated levels, in root nodules of four different B. japonicum host plants. Mixed-inoculation experiments with wild-type and oxc-frc mutant cells revealed that oxalotrophy might be a beneficial trait of B. japonicum at some stage during legume root nodule colonization. PMID:24463964

  15. A Dominant-Negative fur Mutation in Bradyrhizobium japonicum

    PubMed Central

    Benson, Heather P.; LeVier, Kristin; Guerinot, Mary Lou

    2004-01-01

    In many bacteria, the ferric uptake regulator (Fur) protein plays a central role in the regulation of iron uptake genes. Because iron figures prominently in the agriculturally important symbiosis between soybean and its nitrogen-fixing endosymbiont Bradyrhizobium japonicum, we wanted to assess the role of Fur in the interaction. We identified a fur mutant by selecting for manganese resistance. Manganese interacts with the Fur protein and represses iron uptake genes. In the presence of high levels of manganese, bacteria with a wild-type copy of the fur gene repress iron uptake systems and starve for iron, whereas fur mutants fail to repress iron uptake systems and survive. The B. japonicum fur mutant, as expected, fails to repress iron-regulated outer membrane proteins in the presence of iron. Unexpectedly, a wild-type copy of the fur gene cannot complement the fur mutant. Expression of the fur mutant allele in wild-type cells leads to a fur phenotype. Unlike a B. japonicum fur-null mutant, the strain carrying the dominant-negative fur mutation is unable to form functional, nitrogen-fixing nodules on soybean, mung bean, or cowpea, suggesting a role for a Fur-regulated protein or proteins in the symbiosis. PMID:14973020

  16. Antioxidant compounds from the leaves of Peucedanum japonicum thunb.

    PubMed

    Hisamoto, Masashi; Kikuzaki, Hiroe; Ohigashi, Hajime; Nakatani, Nobuji

    2003-08-27

    Seventeen compounds were isolated from the n-butanol soluble fraction of the leaves of Peucedanum japonicum Thunb. On the basis of MS and various NMR spectroscopic techniques, the structures of the isolated compounds were determined as isoquercitrin (1), rutin (2), 3-O-caffeoylquinic acid (3), 4-O-caffeoylquinic acid (4), 5-O-caffeoylquinic acid (5), cnidioside A (6), praeroside II (7), praeroside III (8), apterin (9), esculin (10), (R)-peucedanol (11), (R)-peucedanol 7-O-beta-d-glucopyranoside (12), l-tryptophan (13), uracil (14), guanosine (15), uridine (16), and thymidine (17). All compounds except 11 and 12 were isolated for the first time from P. japonicum. Several isolated compounds were quantified by high-performance liquid chromatography analysis. In addition, all isolated compounds were examined for radical scavenging on 1,1-diphenyl-2-picrylhydrazyl radical and for inhibition of oxidation of liposome induced by 2,2'-azobis(2-amidinopropane)dihydrochloride. Compounds 2-5 were found to be the major potent constituents, which contribute to the antioxidant activity of P. japonicum leaves.

  17. [Alterations in cholesterol, triglyceride and total phospholipid levels in plasma of Callithrix jacchus (sagüi) reinfected by Schistosoma mansoni].

    PubMed

    Ramos, Thadzia Maria de Brito; de Vasconcelos, Amanda Soares; de Carvalho, Vera Cristina Oliveira; Lima, Vera Lúcia de Menezes

    2004-01-01

    Little information is available on the lipid changes caused by Schistosoma mansoni reinfection. In this work it was evaluated alteration in the plasma lipids due to one reinfection by Schistosoma mansoni in the non human primate Callithrix jacchus (sagüi). Blood samples from C. jacchus, prior and after 60 days infection and reinfection, were collected by intravenous puncture, anticoagulated with EDTA (1mg/mL) and centrifuged at 2,500 xg, in order to obtain the plasma. Total cholesterol, cholesteryl ester, total phospholipid and triglyceride levels were determined by spectrophotometer methods. The results showed that there are significant reduction in cholesterol total, cholesteryl ester, total phospholipid and triglyceride concentrations in plasma of animals reinfected by Schistosoma mansoni, in comparison to the same animals prior and after one infection. This study showed that a second infection of Callithrix jacchus by Schistosoma mansoni causes plasma lipid alterations, which are more significant than after a single infection.

  18. Screening trematodes for novel intervention targets: a proteomic and immunological comparison of Schistosoma haematobium, Schistosoma bovis and Echinostoma caproni

    PubMed Central

    HIGÓN, MELISSA; COWAN, GRAEME; NAUSCH, NORMAN; CAVANAGH, DAVID; OLEAGA, ANA; TOLEDO, RAFAEL; STOTHARD, J. RUSSELL; ANTÚNEZ, ORETO; MARCILLA, ANTONIO; BURCHMORE, RICHARD; MUTAPI, FRANCISCA

    2011-01-01

    SUMMARY With the current paucity of vaccine targets for parasitic diseases, particularly those in childhood, the aim of this study was to compare protein expression and immune cross-reactivity between the trematodes Schistosoma haematobium, S. bovis and Echinostoma caproni in the hope of identifying novel intervention targets. Native adult parasite proteins were separated by 2-dimensional gel electrophoresis and identified through electrospray ionisation tandem mass spectrometry to produce a reference gel. Proteins from differential gel electrophoresis analyses of the three parasite proteomes were compared and screened against sera from hamsters infected with S. haematobium and E. caproni following 2-dimensional Western blotting. Differential protein expression between the three species was observed with circa 5% of proteins from S. haematobium showing expression up-regulation compared to the other two species. There was 91% similarity between the proteomes of the two Schistosoma species and 81% and 78·6% similarity between S. haematobium and S. bovis versus E. caproni, respectively. Although there were some common cross-species antigens, species-species targets were revealed which, despite evolutionary homology, could be due to phenotypic plasticity arising from different host-parasite relationships. Nevertheless, this approach helps to identify novel intervention targets which could be used as broad-spectrum candidates for future use in human and veterinary vaccines. PMID:21729355

  19. Schistosoma mansoni soluble egg antigens are internalized by human dendritic cells through multiple C-type lectins and suppress TLR-induced dendritic cell activation.

    PubMed

    van Liempt, Ellis; van Vliet, Sandra J; Engering, Anneke; García Vallejo, Juan Jesus; Bank, Christine M C; Sanchez-Hernandez, Marta; van Kooyk, Yvette; van Die, Irma

    2007-04-01

    In schistosomiasis, a parasitic disease caused by helminths, the parasite eggs induce a T helper 2 cell (T(H)2) response in the host. Here, the specific role of human monocyte-derived dendritic cells (DCs) in initiation and polarization of the egg-specific T cell responses was examined. We demonstrate that immature DCs (iDCs) pulsed with schistosome soluble egg antigens (SEA) do not show an increase in expression of co-stimulatory molecules or cytokines, indicating that no conventional maturation was induced. The ability of SEA to affect the Toll-like receptor (TLR) induced maturation of iDCs was examined by copulsing the DCs with SEA and TLR-ligands. SEA suppressed both the maturation of iDCs induced by poly-I:C and LPS, as indicated by a decrease in co-stimulatory molecule expression and production of IL-12, IL-6 and TNF-alpha. In addition, SEA suppressed T(H)1 responses induced by the poly-I:C-pulsed DCs, and skewed the LPS-induced mixed response towards a T(H)2 response. Immature DCs rapidly internalized SEA through the C-type lectins DC-SIGN, MGL and the mannose receptor and the antigens were targeted to MHC class II-positive lysosomal compartments. The internalization of SEA by multiple C-type lectins may be important to regulate the response of the iDCs to TLR-induced signals.

  20. Formation and Controlled Drug Release Using a Three-Component Supramolecular Hydrogel for Anti-Schistosoma Japonicum Cercariae

    PubMed Central

    Li, Yibao; Zhu, Lei; Fan, Yulan; Li, Yayun; Cheng, Linxiu; Liu, Wei; Li, Xun; Fan, Xiaolin

    2016-01-01

    A novel three-component supramolecular hydrogel based on riboflavin, melamine and amino acid derivatives were constructed for controlled release of pesticides, Niclosamide derivatives. The formation of hydrogel may be attributed to self-assemble via hydrogen bonding and π–π interaction, which have been researched via scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectra. The rheological experiments showed that the hydrogel materials and drug-loaded hydrogel all demonstrated good mechanical strength and high stability. Further experimental results indicated that the drug-loaded hydrogels show large drug loadings, long-term release time and relatively higher efficiency to anti-cercariae in the water environment.

  1. The combined treatment of praziquantel with osteopontin immunoneutralization reduces liver damage in Schistosoma japonicum-infected mice.

    PubMed

    Chen, Bo-Lin; Zhang, Gui-Ying; Wang, Shi-Ping; Li, Qian; Xu, Mei-Hua; Shen, Yue-Ming; Yan, Lu; Gu, Huan; Li, Jia; Huang, Y L; Mu, Yi-Bing

    2012-04-01

    The aim of this study was to evaluate the therapeutic effects of osteopontin neutralization treatment on schistosome-induced liver injury in BALB/C mice. We randomly divided 100 BALB/C mice into groups A, B, C, D and group E. Mice in all groups except group A were abdominally infected with schistosomal cercariae to induce a schistosomal hepatopathological model. Mice in group C, D and group E were respectively administered with praziquantel, praziquantel plus colchicine and praziquantel plus neutralizing osteopontin antibody. We extracted mouse liver tissues at 3 and 9 weeks after the 'stool-eggs-positive' day, observed liver histopathological changes by haematoxylin-eosin and Masson trichrome staining and detected the expression of osteopontin, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta (TGF-β1) by immunohistochemistry, RT-PCR and Western blot. We found that praziquantel plus neutralizing osteopontin antibody treatment significantly decreased the granuloma dimension, the percentage of collagen and the expression of osteopontin, α-SMA and TGF-β1 compared to praziquantel plus colchicine treatment in both the acute and chronic stage of schistosomal liver damage (P<0·05). So we believe that the combined regimen of osteopontin immunoneutralization and anti-helminthic treatment can reduce the granulomatous response and liver fibrosis during the schistosomal hepatopathologic course.

  2. Evaluation of an educational intervention on villagers' knowledge, attitude and behaviour regarding transmission of Schistosoma japonicum in Sichuan province, China.

    PubMed

    Wang, Shuo; Carlton, Elizabeth J; Chen, Lin; Liu, Yang; Spear, Robert C

    2013-09-01

    Health education is an important component of efforts to control schistosomiasis. In China, while education programmes have been implemented intensively, few articles in recent years in either the Chinese or English literature report randomised, controlled interventions of the impacts on knowledge, attitudes and behaviours. Thus, we designed and carried out a cluster-randomised controlled education intervention trial that targeted 706 adults from rural areas in 28 villages in Sichuan, China. We evaluated the effects of the intervention on five endpoints: (1) schistosomiasis knowledge, (2) attitudes towards infection testing and treatment, (3) use of personal protective equipment (PPE), (4) reducing defecation in the field, and (5) reducing dermal contact with potentially contaminated water sources. The results indicated that people in both the intervention and control groups showed improvement in knowledge, attitudes and reduction in field-defecation in the follow-up surveys. However, there was little evidence that suggested statistically significant differences between the two groups regarding any endpoint. Participation in intervention classes was associated with age, gender, occupation and education level. Our study suggests short-term health education interventions may not be effective in improving schistosomiasis knowledge or in the adoption of health-protective behaviours. This might be partially due to the spontaneous learning process of people subject to repeated surveys and other disease control activities. Considering the difficulties of occupation-associated behaviour change and knowledge reinforcement in general, longer-term education programmes should be considered in the future. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Co-infection with Schistosoma mansoni and Human Immunodeficiency Virus-1 (HIV-1) among residents of fishing villages of north-western Tanzania.

    PubMed

    Mazigo, Humphrey D; Dunne, David W; Wilson, Shona; Kinung'hi, Safari M; Pinot de Moira, Angela; Jones, Frances M; Morona, Domenica; Nuwaha, Fred

    2014-12-16

    Co-infection with S. mansoni and Human Immunodeficiency Virus-1 (HIV-1) has been described in sub-Saharan Africa. However, few community-based studies have been conducted to assess the association between the two diseases. The present study examined whether the infection with HIV-1 is associated with an altered susceptibility to S. mansoni infection by comparing the prevalence and intensity of S. mansoni infection among those infected and not infected with HIV-1. Any influence of HIV-1 associated immunodeficiency on the intensity of S. mansoni infection was also investigated. A cross-sectional study was conducted among 1,785 randomly selected adults (aged 21-55 years) in fishing villages of north-western Tanzania. Single stool samples were obtained and examined for S. mansoni eggs using the Kato Katz technique. Finger prick and venous blood samples were collected for HIV-1 screening and CD4(+) cell quantification. Demographic information was collected by questionnaire. Of the 1,785 individuals from whom complete data were obtained, 854 (47.85%, 95% CI; 40.46 - 56.57) were infected with S. mansoni and had a mean intensity of 183.21(95% CI; 165.61-202.70) eggs per gram of faeces (epg). A total of 125 individuals (6.29%, 95% CI 3.59-11.04) were infected with HIV-1 and only 40% (n=50) of them were co-infected with S. mansoni. No differences in prevalence of S. mansoni infection or intensities of infection, as estimated by egg count (epg), were observed between HIV-1 sero-positive individuals and HIV-1 negative individuals. In generalized regression models (adjusted for sex, age, occupation, residence and level of education), being infected with HIV-1 did not increase the risk (APR=1.01, 95%; 0.83-1.21, P=0.93) or intensity (AOR = 0.84, 95% CI; 0.56-1.25, P = 0.33) of S. mansoni infection. Among individuals co-infected with HIV-1 and S. mansoni infection, the intensity of infection (epg) was not associated (P = 0.21) or correlated (P = 0.13) with CD4(+) cell

  4. Cytokine Responses to Schistosoma mansoni and Schistosoma haematobium in Relation to Infection in a Co-endemic Focus in Northern Senegal

    PubMed Central

    Meurs, Lynn; Mbow, Moustapha; Boon, Nele; Vereecken, Kim; Amoah, Abena Serwaa; Labuda, Lucja A.; Dièye, Tandakha Ndiaye; Mboup, Souleymane; Yazdanbakhsh, Maria; Polman, Katja

    2014-01-01

    Background In Africa, many areas are co-endemic for the two major Schistosoma species, S. mansoni and S. haematobium. Epidemiological studies have suggested that host immunological factors may play an important role in co-endemic areas. As yet, little is known about differences in host immune responses and possible immunological interactions between S. mansoni and S. haematobium in humans. The aim of this study was to analyze host cytokine responses to antigens from either species in a population from a co-endemic focus, and relate these to S. mansoni and S. haematobium infection. Methodology Whole blood cytokine responses were investigated in a population in the north of Senegal (n = 200). Blood was stimulated for 72 h with schistosomal egg and adult worm antigens of either Schistosoma species. IL-10, IL-5, IFN-γ, TNF-α, and IL-2 production was determined in culture supernatants. A multivariate (i.e. multi-response) approach was used to allow a joint analysis of all cytokines in relation to Schistosoma infection. Principal Findings Schistosoma haematobium egg and worm antigens induced higher cytokine production, suggesting that S. haematobium may be more immunogenic than S. mansoni. However, both infections were strongly associated with similar, modified Th2 cytokine profiles. Conclusions/Significance This study is the first to compare S. mansoni and S. haematobium cytokine responses in one population residing in a co-endemic area. These findings are in line with previous epidemiological studies that also suggested S. haematobium egg and worm stages to be more immunogenic than those of S. mansoni. PMID:25101661

  5. Susceptibility of Iraqi fresh water snails to infection with Schistosoma haematobium and Schistosoma mansoni Egyptian strains.

    PubMed

    Wajdi, N A; Hussain, W I; El-Hawary, M F

    1979-01-01

    A great number of Egyptian workers and farmers are seeking settlement in Iraq and some of them proved to have either Schistosoma Haematobium (S.h.) or Schistosoma mansoni (S.m) or even mixed infection. Besides, there is the possibility that some of the Iraqi fresh water snails may prove to be susceptible to infection by one or both of the Schistosoma Egyptian strains. The present study deals with investigations on the susceptibility of Iraqi B. truncatus, Gyranaulus ehrenbergi, Physa c.f. fontinalis, Lymnea lagetis, Melanoides tuberculata and Melanopsis nodes by these parasites. Egyptian S. haematobium but not Egyptian S. mansoni infect Iraqi B. truncatus and both proved to be unable to infect any of the other snails included in the study. Yet, the number of cercariae shedded by B. truncatus snails infected with the Egyptian S. haematobium strain, was much less that the number of cercariae shedded by these snails when infected with the Iraqi S. Haematobium strain.

  6. Comparison of two Egyptian strains of Schistosoma mansoni in hamsters.

    PubMed

    Soliman, G N; el Assal, F M; Mansour, N S; Garo, K

    1986-01-01

    In human infection with Schistosoma mansoni from Beni-Suef, the eggs were encountered more frequently in the urine of patients than in infection with S. mansoni from Giza, where eggs were passed into the stool. A comparative study of the two strains of S. mansoni from Beni-Suef and Giza has been carried out in golden hamster. Consistent strain differences were observed. The Beni-Suef strain proved to have lower worm recovery and different egg distribution patterns in tissues of infected hamsters. Worms of both sexes of this strain were larger in size and required a longer period to reach maturity. Hence, the prepatent period was prolonged. Significant differences between the two strains were also noted in the number of eggs per worm. A lower mortality rate and a longer survival time were encountered in hamsters infected with the Beni-Suef strain.

  7. High genetic variability of Schistosoma haematobium in Mali and Nigeria.

    PubMed

    Ezeh, Charles; Yin, Mingbo; Li, Hongyan; Zhang, Ting; Xu, Bin; Sacko, Moussa; Feng, Zheng; Hu, Wei

    2015-02-01

    Schistosoma haematobium is one of the most prevalent parasitic flatworms, infecting over 112 million people in Africa. However, little is known about the genetic diversity of natural S. haematobium populations from the human host because of the inaccessible location of adult worms in the host. We used 4 microsatellite loci to genotype individually pooled S. haematobium eggs directly from each patient sampled at 4 endemic locations in Africa. We found that the average allele number of individuals from Mali was significantly higher than that from Nigeria. In addition, no significant difference in allelic composition was detected among the populations within Nigeria; however, the allelic composition was significantly different between Mali and Nigeria populations. This study demonstrated a high level of genetic variability of S. haematobium in the populations from Mali and Nigeria, the 2 major African endemic countries, suggesting that geographical population differentiation may occur in the regions.

  8. A Novel Alternaria Species Isolated from Peucedanum japonicum in Korea

    PubMed Central

    Deng, Jian Xin; Cho, Hye Sun; Paul, Narayan Chandra; Lee, Hyang Burm

    2014-01-01

    We isolated and examined a new Alternaria sp., which causes leaf spots on Peucedanum japonicum in Korea, by using molecular and morphological methods. Phylogenetic analysis based on a combined internal transcribed spacer region analysis and two protein-coding genes (gpd and Alt a1) demonstrated that the causal fungus was most closely related to A. cinerariae and A. sonchi, and relevant to A. brassicae. However, conidial morphology indicated that it is a novel species within the genus Alternaria, and therefore we have assigned the fungus a new name in this study. PMID:24808728

  9. Antidiabetic coumarin and cyclitol compounds from Peucedanum japonicum.

    PubMed

    Lee, Sung Ok; Choi, Sang Zin; Lee, Jong Hwa; Chung, Sung Hyun; Park, Sang Hyun; Kang, Hee Chol; Yang, Eun Young; Cho, Hi Jae; Lee, Kang Ro

    2004-12-01

    The antidiabetic activity-guided fractionation and isolation of the 80% EtOH extracts from Peucedani Radix (Peucedanum japonicum, Umbelliferae) led to the isolation and characterization of a coumarin and a cyclitol as active principles, that is, peucedanol 7-O-beta-D-glucopyranoside (1) and myo-inositol (2). Their structures were identified by spectroscopic methods. Compound 1 showed 39% inhibition of postprandial hyperglycemia at 5.8 mg/kg dose, and compound 2 also significantly inhibited postprandial hyperglycemia by 34% (P<0.05).

  10. A Novel Alternaria Species Isolated from Peucedanum japonicum in Korea.

    PubMed

    Deng, Jian Xin; Cho, Hye Sun; Paul, Narayan Chandra; Lee, Hyang Burm; Yu, Seung Hun

    2014-03-01

    We isolated and examined a new Alternaria sp., which causes leaf spots on Peucedanum japonicum in Korea, by using molecular and morphological methods. Phylogenetic analysis based on a combined internal transcribed spacer region analysis and two protein-coding genes (gpd and Alt a1) demonstrated that the causal fungus was most closely related to A. cinerariae and A. sonchi, and relevant to A. brassicae. However, conidial morphology indicated that it is a novel species within the genus Alternaria, and therefore we have assigned the fungus a new name in this study.

  11. Discovery of Potent Inhibitors of Schistosoma mansoni NAD⁺ Catabolizing Enzyme.

    PubMed

    Jacques, Sylvain A; Kuhn, Isabelle; Koniev, Oleksandr; Schuber, Francis; Lund, Frances E; Wagner, Alain; Muller-Steffner, Hélène; Kellenberger, Esther

    2015-04-23

    The blood fluke Schistosoma mansoni is the causative agent of the intestinal form of schistosomiasis (or bilharzia). Emergence of Schistosoma mansoni with reduced sensitivity to praziquantel, the drug currently used to treat this neglected disease, has underlined the need for development of new strategies to control schistosomiasis. Our ability to screen drug libraries for antischistosomal compounds has been hampered by the lack of validated S. mansoni targets. In the present work, we describe a virtual screening approach to identify inhibitors of S. mansoni NAD(+) catabolizing enzyme (SmNACE), a receptor enzyme suspected to be involved in immune evasion by the parasite at the adult stage. Docking of commercial libraries into a homology model of the enzyme has led to the discovery of two in vitro micromolar inhibitors. Further structure-activity relationship studies have allowed a 3-log gain in potency, accompanied by a largely enhanced selectivity for the parasitic enzyme over the human homologue CD38.

  12. Mitochondrial gene order change in Schistosoma (Platyhelminthes: Digenea: Schistosomatidae).

    PubMed

    Webster, Bonnie L; Littlewood, D Timothy J

    2012-01-01

    In the flatworm genus Schistosoma, species of which include parasites of biomedical and veterinary importance, mitochondrial gene order is radically different in some species. A PCR-based survey of 19 schistosomatid spp. established which of 14 Schistosoma spp. have the ancestral (plesiomorphic) or derived gene order condition. A phylogeny for Schistosoma was estimated and used to infer the origin of the gene order change which is present in all members of a clade containing Schistosoma incognitum and members of the traditionally recognised Schistosoma indicum, Schistosoma mansoni and Schistosomahaematobium spp. groups. Schistosoma turkestanicum, with the plesiomorphic gene order state, is sister to this clade. Common interval analysis suggests change in gene order, from ancestral to derived, consisted of two sequential transposition events: (a) nad1_nad3 to nad3_nad1 and (b) [atp6,nad2]_[nad3,-nad1,cox1,rrnL,rrnS,cox2,nad6] to [nad3,nad1,cox1,rrnL,rrnS,cox2,nad6]_[atp6,nad2], where gene order offragments within square brackets remain unchanged. Gene order change is rare in parasitic flatworms and is a robust synapomorphy for schistosome spp. that exhibit it. The schistosomatid phylogeny casts some doubt on the origin of Schistosoma (Asian or African), highlights the propensity for species to hosts witch amongst mammalian (definitive) hosts, and indicates the likely importance of snail (intermediate)hosts in determining and defining patterns of schistosome radiation and continental invasion. Mitogenomic sampling of Schistosoma dattai and Schistosoma harinasutai to determine gene order, and within key species, especially S. turkestanicum and S. incognitum, to determine ancestral ranges, may help discover the geographic origins of gene order change in the genus. Samples of S. incognitum from India and Thailand suggest this taxon may include cryptic species. Crown Copyright 2012 Published by Elsevier Ltd. on behalf of Australian Society for Parasitology Inc. Allrights

  13. Of Monkeys and Men: Immunomic Profiling of Sera from Humans and Non-Human Primates Resistant to Schistosomiasis Reveals Novel Potential Vaccine Candidates

    PubMed Central

    Pearson, Mark S.; Becker, Luke; Driguez, Patrick; Young, Neil D.; Gaze, Soraya; Mendes, Tiago; Li, Xiao-Hong; Doolan, Denise L.; Midzi, Nicholas; Mduluza, Takafira; McManus, Donald P.; Wilson, R. Alan; Bethony, Jeffrey M.; Nausch, Norman; Mutapi, Francisca; Felgner, Philip L.; Loukas, Alex

    2015-01-01

    Schistosoma haematobium affects more than 100 million people throughout Africa and is the causative agent of urogenital schistosomiasis. The parasite is strongly associated with urothelial cancer in infected individuals and as such is designated a group I carcinogen by the International Agency for Research on Cancer. Using a protein microarray containing schistosome proteins, we sought to identify antigens that were the targets of protective IgG1 immune responses in S. haematobium-exposed individuals that acquire drug-induced resistance (DIR) to schistosomiasis after praziquantel treatment. Numerous antigens with known vaccine potential were identified, including calpain (Smp80), tetraspanins, glutathione-S-transferases, and glucose transporters (SGTP1), as well as previously uncharacterized proteins. Reactive IgG1 responses were not elevated in exposed individuals who did not acquire DIR. To complement our human subjects study, we screened for antigen targets of rhesus macaques rendered resistant to S. japonicum by experimental infection followed by self-cure, and discovered a number of new and known vaccine targets, including major targets recognized by our human subjects. This study has further validated the immunomics-based approach to schistosomiasis vaccine antigen discovery and identified numerous novel potential vaccine antigens. PMID:25999951

  14. Physiology of ex planta nitrogenase activity in Rhizobium japonicum

    SciTech Connect

    Agarwal, A.K.; Keister, D.L.

    1983-05-01

    Thirty-nine wild-type strains of Rhizobium japonicum have been studied for their ability to synthesize nitrogenase ex planta in defined liquid media under microaerobic conditions. Twenty-one produced more than trace amounts of acetylene reduction activity, but only a few of these yielded high activity. The oxygen response curves were similar for most of the nitrogenase-positive strains. The strains derepressible for activity had several phenotypic characteristics different from non-derepressible strains. These included slower growth and lower oxygen consumption under microaerobic conditions and lower extracellular polysaccharide production. Extracellular polysaccharide production during growth on gluconate in every nitrogenase-positive strain assayed was lower under both aerobic and microaerobic conditions than the non-depressible strains. These phenotypic characteristics may be representative of a genotype of a subspecies of R. japonicum. These studies were done in part to enlarge the base number of strains available for studies on the physiology, biochemistry, and genetics of nitrogen fixation. (35 Refs.)

  15. Development of an immunodiagnosis method using recombinant PsCP for detection of Paragonimus skrjabini infection in human.

    PubMed

    Yu, Shasha; Zhang, Xilin; Chen, Wenbi; Zheng, Hong; Ai, Guoping; Ye, Nan; Wang, Ying

    2017-01-01

    Paragonimiasis skrjabini is a kind of zoonosis and prevalent in 16 provinces in China, such as Chongqing, Fujian, Sichuan, and Yunnan. However, sensitive and efficient diagnostic methods for the infection are limited. In order to provide a more convenient and simple method for serologic diagnosis, the recombinant P. skrjabini cysteine protease (PsCP) was expressed, purified, and then used to develop an indirect enzyme-linked immunosorbent assay (ELISA) for detecting anti-PsCP antibodies in human. Given the positive/negative cutoff value as 0.606, the maximum dilution of human sera in which anti-PsCP antibodies could be detected was 1:12,800. In addition, the coefficients of variation (CVs) of inter-assay and intra-assay experiments were both below 10 %. Furthermore, the sensitivity of the PsCP-based ELISA was 95.5 %, and the indirect ELISA displays no cross-reactivity with human antisera against Echinococcus granulosus, Taenia solium, Schistosoma japonicum, and Trichinella spiralis, either. In conclusion, recombinant PsCP was readily produced and used to establish a simple PsCP-based ELISA that provided a highly specific and sensitive method for analysis of clinical samples. Besides, the method can also probably be used to diagnose P. skrjabini infection in animals.

  16. Reiteration of genes involved in symbiotic nitrogen fixation by fast-growing Rhizobium japonicum.

    PubMed Central

    Prakash, R K; Atherly, A G

    1984-01-01

    By using cloned Rhizobium meliloti nodulation (nod) genes and nitrogen fixation (nif) genes, we found that the genes for both nodulation and nitrogen fixation were on a plasmid present in fast-growing Rhizobium japonicum strains. Two EcoRI restriction fragments from a plasmid of fast-growing R. japonicum hybridized with nif structural genes of R. meliloti, and three EcoRI restriction fragments hybridized with the nod clone of R. meliloti. Cross-hybridization between the hybridizing fragments revealed a reiteration of nod and nif DNA sequences in fast-growing R. japonicum. Both nif structural genes D and H were present on 4.2- and 4.9-kilobase EcoRI fragments, whereas nifK was present only on the 4.2-kilobase EcoR2 fragment. These results suggest that the nif gene organizations in fast-growing and in slow-growing R. japonicum strains are different. Images PMID:6094491

  17. [Glutamate dehydrogenase activity of Bradyrhizobium japonicum in the presence of phytoregulators].

    PubMed

    Leonova, N O; Tytova, L V; Tantsiurenko, O V; Antypchuk, A F

    2006-01-01

    Influence of plant growth regulators ivin and emistim C, and flavonoids daidzein and quercetin on the glutamate dehydrogenase activity of soybean nodule bacteria, with contrasting symbiotic properties, were studied. It was shown that all used phytoregulators stimulated glutamate dehydrogenase activity of Bradyrhizobium japonicum 71t (the strain with highly efficient symbiotic properties) 1.2-4.9 times. Bradyrhizobium japonicum 21110 (the strain with inefficient symbiotic properties) diminished the enzyme activity in the presence of all phythoregulators except for ivin.

  18. Schistosoma mansoni: cercarial responses to irradiance changes

    SciTech Connect

    Saladin, K.S.

    1982-02-01

    Cercariae of Schistosoma mansoni alternate between active swimming and passive drifting. They began swimming in response to either an increase or decrease in irradiance experienced during the passive phase. The number of cercariae reacting to a shadow was proportional to the magnitude of the stimulus. The shadow response may be mediated by the cercaria's ciliary receptors. About half as many cercariae reacted to an irradiance increase as to an equivalent decrease. This report is the first quantitative study of photosensory stimulus-response relationships in schistosome cercariae.

  19. Praziquantel inhibits Schistosoma mansoni attachment in vitro.

    PubMed

    da-Silva, S P; Noel, F

    1990-01-01

    Male adult Schistosoma mansoni worms were placed in a glass dish containing Tyrode solution and observed for 15 min after addition of praziquantel (0.01 to 1 microM). Praziquantel promoted a concentration- and time-dependent inhibition of sucker-mediated attachment of the worm. Attachment inhibition was correlated with shortening of the parasite. We propose that the rapid and total inhibition of worm attachment observed in vitro with 1 microM praziquantel indicates that therapeutic concentrations of this drug should promote a rapid hepatic shift, in vivo, which may facilitate host tissue reaction.

  20. Role of pili (fimbriae) in attachment of Bradyrhizobium japonicum to soybean roots

    SciTech Connect

    Vesper, S.J.; Bauer, W.D.

    1986-07-01

    Pili (fimbriae) were observed on cells of each of the five strains of Bradyrhizobium japonicum and the one strain of Rhizobium trifolii examined. Pili on B. japonicum were about 4 nm in diameter and polarly expressed. Piliated cells were estimated by transmission electron microscopy and hydrophobic attachment to polystyrene to constitute only a small percentage of the total population. The proportion of piliated cells in these populations was dependent on culture age in some strains. Piliated B. japonicum cells were selectively and quantitatively removed from suspension when cultures were incubated with either soybean roots or hydrophobic plastic surfaces, indicating that pili were involved in the attachment of the bacteria to these surfaces. Pili from B. japonicum 110 ARS were purified and found to have a subunit molecular weight of approximately 21,000. Treatment of B. japonicum suspensions with antiserum against the isolated pili reduced attachment to soybean roots by about 90% and nodulation by about 80%. Pili appear to be important mediators of attachment of B. japonicum to soybean roots under the conditions examined.

  1. Cirsium japonicum flavones enhance adipocyte differentiation and glucose uptake in 3T3-L1 cells.

    PubMed

    Liao, Zhiyong; Wu, Zhihua; Wu, Mingjiang

    2012-01-01

    Cirsium japonicum flavones have been demonstrated to possess anti-diabetic effects in diabetic rats, but the functional mechanism remains unknown. The nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) plays an important role in glucose and lipid homeostasis. In this study, we report the effects of Cirsium japonicum flavones (pectolinarin and 5,7-dihydroxy-6,4-dimethoxy flavone) on PPARγ activation, adipocyte differentiation, and glucose uptake in 3T3-L1 cells. Reporter gene assays and Oil Red O staining showed that Cirsium japonicum flavones induced PPARγ activation and enhanced adipocyte differentiation of 3T3-L1 cells in a dose-dependent manner. In addition, Cirsium japonicum flavones increased the expression of PPARγ target genes, such as adiponectin and glucose transporter 4 (GLUT4), and enhanced the translocation of intracellular GLUT4 to the plasma membrane. In mature 3T3-L1 adipocytes, Cirsium japonicum flavones significantly enhanced the basal and insulin-stimulated glucose uptake. The flavones-induced effects in 3T3-L1 cells were abolished by the PPARγ antagonist, GW9662, and by the phosphatidylinositol 3-kinase (PI3K) inhibitor, wortmannin. This study suggests that Cirsium japonicum flavones promote adipocyte differentiation and glucose uptake by inducing PPARγ activation and then modulating the insulin signaling pathway in some way, which could benefit diabetes patients.

  2. Isolation and characterization of the lipopolysaccharides from Bradyrhizobium japonicum.

    PubMed Central

    Carrion, M; Bhat, U R; Reuhs, B; Carlson, R W

    1990-01-01

    The lipopolysaccharide (LPS) of Bradyrhizobium japonicum 61A123 was isolated and partially characterized. Phenol-water extraction of strain 61A123 yielded LPS exclusively in the phenol phase. The water phase contained low-molecular-weight glucans and extracellular or capsular polysaccharides. The LPSs from B. japonicum 61A76, 61A135, and 61A101C were also extracted exclusively into the phenol phase. The LPSs from strain USDA 110 and its Nod- mutant HS123 were found in both the phenol and water phases. The LPS from strain 61A123 was further characterized by polyacrylamide gel electrophoresis, composition analysis, and 1H and 13C nuclear magnetic resonance spectroscopy. Analysis of the LPS by polyacrylamide gel electrophoresis showed that it was present in both high- and low-molecular-weight forms (LPS I and LPS II, respectively). Composition analysis was also performed on the isolated lipid A and polysaccharide portions of the LPS, which were purified by mild acid hydrolysis and gel filtration chromatography. The major components of the polysaccharide portion were fucose, fucosamine, glucose, and mannose. The intact LPS had small amounts of 2-keto-3-deoxyoctulosonic acid. Other minor components were quinovosamine, glucosamine, 4-O-methylmannose, heptose, and 2,3-diamino-2,3-dideoxyhexose. The lipid A portion of the LPS contained 2,3-diamino-2,3-dideoxyhexose as the only sugar component. The major fatty acids were beta-hydroxymyristic, lauric, and oleic acids. A long-chain fatty acid, 27-hydroxyoctacosanoic acid, was also present in this lipid A. Separation and analysis of LPS I and LPS II indicated that glucose, mannose, 4-O-methylmannose, and small amounts of 2,2-diamino-2,3-dideozyhexose and heptose were components of the core region of the LPS, whereas fucose, fucosmine, mannose, and small amounts of quinovosamine and glucosamine were components of the LPS O-chain region. Images FIG. 1 PMID:2318801

  3. Schistosoma mattheei--an ovum containing twin miracidia.

    PubMed

    Van Rensburg, L J; Van Wyk, J A

    2003-03-01

    A large Schistosoma mettheei ovum containing two miracidia was recovered from a squash preparation of the liver of an experimentally infected hamster. When observed, the miracidia were motile and facing in opposite directions.

  4. Schistosoma mansoni cercariae swim efficiently by exploiting an elastohydrodynamic coupling

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, Deepak; Katsikis, Georgios; Bhargava, Arjun; Prakash, Manu

    2017-03-01

    The motility of many parasites is critical for infecting their host, as exemplified in the transmission cycle of the parasite Schistosoma mansoni. In its human infectious stage, submillimetre-scale forms of the parasite known as cercariae swim in freshwater and infect humans by penetrating the skin. This infection causes schistosomiasis, a disease comparable to malaria in global socio-economic impact. Given that cercariae do not feed and hence have a lifetime of around 12 hours, efficient motility is crucial for schistosomiasis transmission. Despite this, a first-principles understanding of how cercariae swim is lacking. Combining biological experiments, a novel theoretical model and its robotic realization, we show that cercariae use their forked tail to swim against gravity using a novel swimming gait, described here as a `T-swimmer gait'. During this gait, cercariae beat their tail periodically while maintaining an increased flexibility near their posterior and anterior ends. This flexibility allows an interaction between fluid drag and bending resistance--an elastohydrodynamic coupling, to naturally break time-reversal symmetry and enable locomotion at small length scales. Finally, we find that cercariae maintain this flexibility at an optimal regime for efficient swimming. We anticipate that our work sets the ground for linking the swimming of cercariae to disease transmission, and could potentially enable explorations of novel strategies for schistosomiasis control and prevention.

  5. Molecular epidemiology and phylogeography of Schistosoma mansoni around Lake Victoria.

    PubMed

    Standley, C J; Kabatereine, N B; Lange, C N; Lwambo, N J S; Stothard, J R

    2010-11-01

    Intestinal schistosomiasis continues to be a major public health problem in sub-Saharan Africa, and is endemic in communities around Lake Victoria. Interest is growing in the molecular evolution and population genetic structure of Schistosoma mansoni and we describe a detailed analysis of the molecular epidemiology and phylogeography of S. mansoni from Lake Victoria. In total, 388 cytochrome oxidase 1 (COI) sequences were obtained from 25 sites along the Ugandan, Tanzanian and Kenyan shorelines of Lake Victoria, and 122 unique barcodes were identified; 9 corresponded to previously discovered barcodes from Lakes Victoria and Albert. A subset of the data, composed of COI sequences from miracidia from 10 individual children, was used for population genetics analyses; these results were corroborated by microsatellite analysis of 4 isolates of lab-passaged adult worms. Overall, 12 barcodes were found to be shared across all 3 countries, whereas the majority occurred singly and were locally restricted. The population genetics analyses were in agreement in revealing high diversity at the level of the human host and negligible population structuring by location. The lack of correlation between genetic distance and geographical distance in these data may be attributed to the confounding influence of high intra-individual diversity as well as human migration between communities.

  6. Schistosoma mansoni cercariae swim efficiently by exploiting an elastohydrodynamic coupling

    NASA Astrophysics Data System (ADS)

    Krishnamurthy, Deepak; Katsikis, Georgios; Bhargava, Arjun; Prakash, Manu

    2016-10-01

    The motility of many parasites is critical for infecting their host, as exemplified in the transmission cycle of the parasite Schistosoma mansoni. In its human infectious stage, submillimetre-scale forms of the parasite known as cercariae swim in freshwater and infect humans by penetrating the skin. This infection causes schistosomiasis, a disease comparable to malaria in global socio-economic impact. Given that cercariae do not feed and hence have a lifetime of around 12 hours, efficient motility is crucial for schistosomiasis transmission. Despite this, a first-principles understanding of how cercariae swim is lacking. Combining biological experiments, a novel theoretical model and its robotic realization, we show that cercariae use their forked tail to swim against gravity using a novel swimming gait, described here as a `T-swimmer gait'. During this gait, cercariae beat their tail periodically while maintaining an increased flexibility near their posterior and anterior ends. This flexibility allows an interaction between fluid drag and bending resistance--an elastohydrodynamic coupling, to naturally break time-reversal symmetry and enable locomotion at small length scales. Finally, we find that cercariae maintain this flexibility at an optimal regime for efficient swimming. We anticipate that our work sets the ground for linking the swimming of cercariae to disease transmission, and could potentially enable explorations of novel strategies for schistosomiasis control and prevention.

  7. Human Schistosomiasis: Clinical Perspective: Review

    PubMed Central

    Barsoum, Rashad S.; Esmat, Gamal; El-Baz, Tamer

    2013-01-01

    The clinical manifestations of schistosomiasis pass by acute, sub acute and chronic stages that mirror the immune response to infection. The later includes in succession innate, TH1 and TH2 adaptive stages, with an ultimate establishment of concomitant immunity. Some patients may also develop late complications, or suffer the sequelae of co-infection with other parasites, bacteria or viruses. Acute manifestations are species-independent; occur during the early stages of invasion and migration, where infection-naivety and the host’s racial and genetic setting play a major role. Sub acute manifestations occur after maturity of the parasite and settlement in target organs. They are related to the formation of granulomata around eggs or dead worms, primarily in the lower urinary tract with Schistosoma haematobium, and the colon and rectum with Schistosoma mansoni, Schistosoma japonicum, Schistosoma intercalatum and Schistosoma mekongi infection. Secondary manifestations during this stage may occur in the kidneys, liver, lungs or other ectopic sites. Chronic morbidity is attributed to the healing of granulomata by fibrosis and calcification at the sites of oval entrapment, deposition of schistosomal antigen-antibody complexes in the renal glomeruli or the development of secondary amyloidosis. Malignancy may complicate the chronic lesions in the urinary bladder or colon. Co-infection with salmonella or hepatitis viruses B or C may confound the clinical picture of schistosomiasis, while the latter may have a negative impact on the course of other co-infections as malaria, leishmaniasis and HIV. Prevention of schistosomiasis is basically geared around education and periodic mass treatment, an effective vaccine being still experimental. Praziquantel is the drug of choice in the treatment of active infection by any species, with a cure rate of 80%. Other antischistosomal drugs include metrifonate for S. haematobium, oxamniquine for S. mansoni and Artemether and, possibly

  8. Human water contacts patterns in Schistosoma mansoni epidemic foci in northern Senegal change according to age, sex and place of residence, but are not related to intensity of infection.

    PubMed

    Scott, J T; Diakhaté, M; Vereecken, K; Fall, A; Diop, M; Ly, A; De Clercq, D; de Vlas, S J; Berkvens, D; Kestens, L; Gryseels, B

    2003-02-01

    In an epidemic focus in northern Senegal, adults had lower intensities of infection than adolescents, a phenomenon that could not be attributed to immunity acquired over the previous 10-15 years of exposure to the parasite because all age groups had had the same number of years' experience of the worm. This article considers whether this pattern could have been because of higher levels of exposure to the parasite in younger age groups. Personal contact with infected water was recorded using a questionnaire in Schistosoma mansoni foci not more than 3 years old and in another, 10-year-old focus. Many aspects of contact (e.g. frequency, duration or time of day of contact) may contribute to the number of encounters with infective cercariae (true exposure), so various assumptions regarding the relationship between water contact and true exposure were tested resulting in a range of exposure indices. People reported a mean of 4.4 separate contacts, and spent a median of 57 min per day in water. Patterns of water contact differed depending on the exposure index used, e.g. considering duration, males spent a longer time in water than females (P < 0.001). But using frequency, females had more contacts with water than males in most villages (P < 0.001). Generally, exposure levels dropped as people become aged (P < 0.001) and residents of the older focus were more exposed than residents of other foci (P < 0.002). Intensity of (re)infection was not related to exposure either alone or in models incorporating age, sex and/or village irrespective of the index used. There is therefore evidence that age, sex and place of residence determine exposure but none to suggest that exposure had an influence on the relationship between these factors and intensity of infection. We propose therefore that in this population other factors have principal importance in determining intensity of infection.

  9. Branchiostoma japonicum and B. belcheri are distinct lancelets (Cephalochordata) in Xiamen waters in China.

    PubMed

    Zhang, Qiu-Jin; Zhong, Jing; Fang, Shao-Hua; Wang, Yi-Quan

    2006-06-01

    Lancelets in Xiamen were reported as Branchiostoma belcheri in 1932, and subsequently were believed to comprise a single species. However, recent studies revealed that Xiamen lancelets actually represent two species, B. belcheri and B. japonicum. We observed thousands of lancelets from Xiamen beach to recognize these two species. Our observations showed that at least three morphological characters distinguish them: 1) the rostral fin is slightly round with the end obtuse in B. belcheri but elliptic with the end cuspate in B. japonicum; 2) the number of preanal fin-chambers is more than 80 in B. belcheri but less than 64 in B. japonicum, and the chambers are slender in the former but stout in the latter; 3) the caudal fin of B. belcheri is narrower than that of B. japonicum, and the angle between the dorsal and super-caudal fins, and between preanal and sub-caudal fins, is obtuse in B. belcheri but acute in B. japonicum. We also provide some ecological and distributional evidence to support the conclusion that there are two separate species in Xiamen waters.

  10. Ganoderma neo-japonicum Imazeki revisited: Domestication study and antioxidant properties of its basidiocarps and mycelia

    PubMed Central

    Tan, Wee-Cheat; Kuppusamy, Umah Rani; Phan, Chia-Wei; Tan, Yee-Shin; Raman, Jegadeesh; Anuar, Azliza Mad; Sabaratnam, Vikineswary

    2015-01-01

    Mushroom cultivation benefits humankind as it deliberately encourages wild mushrooms to be commercially propagated while recycling agricultural wastes. Ganoderma neo-japonicum is a rare polypore mushroom found growing on decaying Schizostachyum brachycladium (a tropical bamboo) clumps in Malaysia. The Malaysian indigenous tribes including the Temuans and Temiars use the basidiocarps of G. neo-japonicum to treat various ailments including diabetes. In this study, the domestication of G. neo-japonicum in artificial logs of different agricultural residues was investigated. Sawdust promoted the mycelia spawn colonisation in the shortest period of 38 ± 0.5 days. However, only sawdust and bamboo dust supported the primodia formation. Complex medium supported mycelium growth in submerged cultures and 27.11 ± 0.43 g/L of mycelia was obtained after 2 weeks of cultivation at 28 °C and 200 rpm. Antioxidant potential in mushroom may be influenced by different cultivation and extraction methods. The different extracts from the wild and cultivated basidiocarps as well as mycelia were then tested for their antioxidant properties. Aqueous and ethanol extracts of mycelia and basidiocarps tested had varying levels of antioxidant activities. To conclude, domestication of wild G. neo-japonicum using agroresidues may ensure a continuous supply of G. neo-japonicum for its medicinal use while ensuring the conservation of this rare species. PMID:26213331

  11. Effects of indole-3-acetic acid on the transcriptional activities and stress tolerance of Bradyrhizobium japonicum.

    PubMed

    Donati, Andrew J; Lee, Hae-In; Leveau, Johan H J; Chang, Woo-Suk

    2013-01-01

    A genome-wide transcriptional profile of Bradyrhizobium japonicum, the nitrogen-fixing endosymbiont of the soybean plant, revealed differential expression of approximately 15% of the genome after a 1 mM treatment with the phytohormone indole-3-acetic acid (IAA). A total of 1,323 genes were differentially expressed (619 up-regulated and 704 down-regulated) at a two-fold cut off with q value ≤ 0.05. General stress response genes were induced, such as those involved in response to heat, cold, oxidative, osmotic, and desiccation stresses and in exopolysaccharide (EPS) biosynthesis. This suggests that IAA is effective in activating a generalized stress response in B. japonicum. The transcriptional data were corroborated by the finding that stress tolerance of B. japonicum in cell viability assays was enhanced when pre-treated with 1 mM IAA compared to controls. The IAA treatment also stimulated biofilm formation and EPS production by B. japonicum, especially acidic sugar components in the total EPS. The IAA pre-treatment did not influence the nodulation ability of B. japonicum. The data provide a comprehensive overview of the potential transcriptional responses of the symbiotic bacterium when exposed to the ubiquitous hormone of its plant host.

  12. Effects of Indole-3-Acetic Acid on the Transcriptional Activities and Stress Tolerance of Bradyrhizobium japonicum

    PubMed Central

    Donati, Andrew J.; Lee, Hae-In; Leveau, Johan H. J.; Chang, Woo-Suk

    2013-01-01

    A genome-wide transcriptional profile of Bradyrhizobium japonicum, the nitrogen-fixing endosymbiont of the soybean plant, revealed differential expression of approximately 15% of the genome after a 1 mM treatment with the phytohormone indole-3-acetic acid (IAA). A total of 1,323 genes were differentially expressed (619 up-regulated and 704 down-regulated) at a two-fold cut off with q value ≤ 0.05. General stress response genes were induced, such as those involved in response to heat, cold, oxidative, osmotic, and desiccation stresses and in exopolysaccharide (EPS) biosynthesis. This suggests that IAA is effective in activating a generalized stress response in B. japonicum. The transcriptional data were corroborated by the finding that stress tolerance of B. japonicum in cell viability assays was enhanced when pre-treated with 1 mM IAA compared to controls. The IAA treatment also stimulated biofilm formation and EPS production by B. japonicum, especially acidic sugar components in the total EPS. The IAA pre-treatment did not influence the nodulation ability of B. japonicum. The data provide a comprehensive overview of the potential transcriptional responses of the symbiotic bacterium when exposed to the ubiquitous hormone of its plant host. PMID:24098533

  13. Genetic Manipulation of Schistosoma haematobium, the Neglected Schistosome

    PubMed Central

    Rinaldi, Gabriel; Okatcha, Tunika I.; Popratiloff, Anastas; Ayuk, Mary A.; Suttiprapa, Sutas; Mann, Victoria H.; Liang, Yung-san; Lewis, Fred A.; Loukas, Alex; Brindley, Paul J.

    2011-01-01

    Background Minimal information on the genome and proteome of Schistosoma haematobium is available, in marked contrast to the situation with the other major species of human schistosomes for which draft genome sequences have been reported. Accordingly, little is known about functional genomics in S. haematobium, including the utility or not of RNA interference techniques that, if available, promise to guide development of new interventions for schistosomiasis haematobia. Methods/Findings Here we isolated and cultured developmental stages of S. haematobium, derived from experimentally infected hamsters. Targeting different developmental stages, we investigated the utility of soaking and/or square wave electroporation in order to transfect S. haematobium with nucleic acid reporters including Cy3-labeled small RNAs, messenger RNA encoding firefly luciferase, and short interfering RNAs (siRNAs). Three hours after incubation of S. haematobium eggs in 50 ng/µl Cy3-labeled siRNA, fluorescent foci were evident indicating that labeled siRNA had penetrated into miracidia developing within the egg shell. Firefly luciferase activity was detected three hours after square wave electroporation of the schistosome eggs and adult worms in 150 ng/µl of mRNA. RNA interference knockdown (silencing) of reporter luciferase activity was seen following the introduction of dsRNA specific for luciferase mRNA in eggs, schistosomules and mixed sex adults. Moreover, introduction of an endogenous gene-specific siRNA into adult schistosomes silenced transcription of tetraspanin 2 (Sh-tsp-2), the apparent orthologue of the Schistosoma mansoni gene Sm-tsp-2 which encodes the surface localized structural and signaling protein Sm-TSP-2. Together, knockdown of reporter luciferase and Sh-tsp-2 indicated the presence of an intact RNAi pathway in S. haematobium. Also, we employed laser scanning confocal microscopy to view the adult stages of S. haematobium. Conclusions These findings and approaches

  14. Alterations of ciliate phosducin phosphorylation in Blepharisma japonicum cells.

    PubMed

    Sobierajska, Katarzyna; Fabczak, Hanna; Fabczak, Stanisław

    2005-05-13

    We have previously reported that motile photophobic response in ciliate Blepharisma japonicum correlates with dephosphorylation of a cytosolic 28 kDa phosphoprotein (PP28) exhibiting properties similar to those of phosducin. Here we demonstrate in in vivo phosphorylation assay that the light-elicited dephosphorylation of the PP28 is significantly modified by cell incubation with substances known to modulate protein phosphatase and kinase activities. Immunoblot analyses showed that incubation of ciliates with okadaic acid and calyculin A, potent inhibitors of type 1 or 2A protein phosphatases, distinctly increased phosphorylation of PP28 in dark-adapted cells and markedly weakened dephosphorylation of the ciliate phosducin following cell illumination. An enhancement of PP28 phosphorylation was also observed in dark-adapted ciliates exposed to 8-Br-cAMP and 8-Br-cGMP, slowly hydrolysable cyclic nucleotide analogs and 3-isobutyryl-1-methylxanthine (IBMX), a non-specific cyclic nucleotide phosphodiesterase (PDEs) inhibitor. Only slight changes in light-evoked dephosphorylation levels of PP28 were observed in cells treated with the cyclic nucleotide analogs and IBMX. Incubation of ciliates with H 89 or KT 5823, highly selective inhibitor of cAMP-dependent protein kinase (PKA) and cGMP-dependent protein kinase (PKG), respectively, decreased PP28 phosphorylation levels in dark-adapted cells, whereas the extent of light-evoked dephosphorylation of the phosphoprotein was only slightly influenced. Cell treatment with higher Ca2+ concentration together with ionophore A23187 in culture medium resulted in marked increase in PP28 phosphorylation levels, while quite an opposite effect was observed in cells exposed to Ca2+ chelators, EGTA or BAPTA/AM as well as calmodulin antagonists, such as trifluoperazine (TFP), W-7 or calmidazolium. Light-dependent dephosphorylation was not considerably affected by these treatments. The experimental findings presented here suggest that an

  15. Analysis of Two Polyhydroxyalkanoate Synthases in Bradyrhizobium japonicum USDA 110

    PubMed Central

    Mongiardini, Elías J.; Pérez-Giménez, Julieta; Parisi, Gustavo; Lodeiro, Aníbal R.

    2013-01-01

    Bradyrhizobium japonicum USDA 110 has five polyhydroxyalkanoate (PHA) synthases (PhaC) annotated in its genome: bll4360 (phaC1), bll6073 (phaC2), blr3732 (phaC3), blr2885 (phaC4), and bll4548 (phaC5). All these proteins possess the catalytic triad and conserved amino acid residues of polyester synthases and are distributed into four different PhaC classes. We obtained mutants in each of these paralogs and analyzed phaC gene expression and PHA production in liquid cultures. Despite the genetic redundancy, only phaC1 and phaC2 were expressed at significant rates, while PHA accumulation in stationary-phase cultures was impaired only in the ΔphaC1 mutant. Meanwhile, the ΔphaC2 mutant produced more PHA than the wild type under this condition, and surprisingly, the phaC3 transcript increased in the ΔphaC2 background. A double mutant, the ΔphaC2 ΔphaC3 mutant, consistently accumulated less PHA than the ΔphaC2 mutant. PHA accumulation in nodule bacteroids followed a pattern similar to that seen in liquid cultures, being prevented in the ΔphaC1 mutant and increased in the ΔphaC2 mutant in relation to the level in the wild type. Therefore, we used these mutants, together with a ΔphaC1 ΔphaC2 double mutant, to study the B. japonicum PHA requirements for survival, competition for nodulation, and plant growth promotion. All mutants, as well as the wild type, survived for 60 days in a carbon-free medium, regardless of their initial PHA contents. When competing for nodulation against the wild type in a 1:1 proportion, the ΔphaC1 and ΔphaC1 ΔphaC2 mutants occupied only 13 to 15% of the nodules, while the ΔphaC2 mutant occupied 81%, suggesting that the PHA polymer is required for successful competitiveness. However, the bacteroid content of PHA did not affect the shoot dry weight accumulation. PMID:23667236

  16. Importance of the aquatic weed Ceratophyllum to transmission of Schistosoma haematobium in the Volta Lake, Ghana*

    PubMed Central

    Klumpp, R. K.; Chu, K. Y.

    1980-01-01

    Results of 5 years of sampling for Bulinus rohlfsi in human-water contact sites of villages along the Volta Lake, Ghana, have confirmed that the aquatic macrophyte, Ceratophyllum, is the most important ecological factor for sustaining high levels of cercarial transmission of Schistosoma haematobium. Data available so far indicate that growth of this weed largely determines the size of the snail populations. Increasing density of Ceratophyllum correlates with increasing levels of cercarial transmission potential in the water contact sites and of S. haematobium infection in the village populations. PMID:6975187

  17. Isolation and characterization of novel microsatellite loci for the endangered orchid Cypripedium japonicum (Orchidaceae)1

    PubMed Central

    Yamashita, Yumi; Izuno, Ayako; Isagi, Yuji; Kurosawa, Takahide; Kaneko, Shingo

    2016-01-01

    Premise of the study: Twenty-six microsatellite markers were developed for the endangered orchid Cypripedium japonicum (Orchidaceae) to estimate the clonal diversity and genetic structure of the remaining populations in Japan. Methods and Results: Microsatellite loci of C. japonicum were isolated using Ion Personal Genome Machine (PGM) sequencing. The primer sets were tested on 55 ramets sampled from two populations in Japan. Sixteen loci showed polymorphism in at least one population, with two to five alleles per locus. Observed and expected heterozygosities for the two populations ranged from 0.00 to 0.92 and 0.00 to 0.71, respectively. Conclusions: The microsatellite markers developed here provide a useful tool to analyze clonal structure and sexual regeneration status and will help to manage the remaining genetic variation within C. japonicum. PMID:26949576

  18. Distribution of Rhizosphere and Endosphere Fungi on the First-Class Endangered Plant Cypripedium japonicum.

    PubMed

    Gang, Geun-Hye; Cho, Gyeongjun; Kwak, Youn-Sig; Park, Eun-Hee

    2017-06-01

    Endangered native plant habitats and populations are rapidly disappearing because of climate and environmental changes. As a representative, the abundance of the first-class endangered wild plant, Cypripedium japonicum, has been rapidly decreasing in Korea. The purpose of this study was to evaluate the distribution of rhizosphere and endophytic fungi on C. japonicum in its native habitat. A total of 440 rhizosphere and 79 endosphere fungi isolates were isolated and identified on the basis of their molecular characteristics. Sixty-five genera and 119 fungi species were identified in this study. The genus Trichoderma showed the highest abundance among both rhizosphere and endosphere fungi. Mortierella, Hypocrea, and Penicillium spp. were also relatively dominant species on C. japonicum. The community structures of rhizosphere and endosphere fungi were similar, but endosphere fungi showed greater diversity.

  19. Developmental anatomy of the reproductive shoot in Hydrobryum japonicum (Podostemaceae).

    PubMed

    Katayama, Natsu; Koi, Satoshi; Kato, Masahiro

    2008-07-01

    Podostemaceae are unusual aquatic angiosperms adapting to extreme habitats, i.e., rapids and waterfalls, and have unique morphologies. We investigated the developmental anatomy of reproductive shoots scattered on crustose roots of Hydrobryum japonicum by scanning electron microscopy and using semi-thin serial sections. Two developmental patterns were observed: bracts arise either continuously from an area of meristematic cells that has produced leaves, or within differentiated root ground tissue beneath, and internal to, leaf base scars after an interruption. In both patterns, the bract primordia arise endogenously at the base of youngest bracts in the absence of shoot apical meristem, involving vacuolated-cell detachment to each bract separately. The different transition patterns of reproductive shoot development may be caused by different stages of parental vegetative shoots. The floral meristem arises between the two youngest bracts, and is similarly accompanied by cell degeneration. In contrast, the floral organs, including the spathella, arise exogenously from the meristem. Bract development, like vegetative leaf development, is unique to this podostemad, while floral-organ development is conserved.

  20. Evolutionary Instability of Symbiotic Function in Bradyrhizobium japonicum

    PubMed Central

    Sachs, Joel L.; Russell, James E.; Hollowell, Amanda C.

    2011-01-01

    Bacterial mutualists are often acquired from the environment by eukaryotic hosts. However, both theory and empirical work suggest that this bacterial lifestyle is evolutionarily unstable. Bacterial evolution outside of the host is predicted to favor traits that promote an independent lifestyle in the environment at a cost to symbiotic function. Consistent with these predictions, environmentally-acquired bacterial mutualists often lose symbiotic function over evolutionary time. Here, we investigate the evolutionary erosion of symbiotic traits in Bradyrhizobium japonicum, a nodulating root symbiont of legumes. Building on a previous published phylogeny we infer loss events of nodulation capability in a natural population of Bradyrhizobium, potentially driven by mutation or deletion of symbiosis loci. Subsequently, we experimentally evolved representative strains from the symbiont population under host-free in vitro conditions to examine potential drivers of these loss events. Among Bradyrhizobium genotypes that evolved significant increases in fitness in vitro, two exhibited reduced symbiotic quality, but no experimentally evolved strain lost nodulation capability or evolved any fixed changes at six sequenced loci. Our results are consistent with trade-offs between symbiotic quality and fitness in a host free environment. However, the drivers of loss-of-nodulation events in natural Bradyrhizobium populations remain unknown. PMID:22073160

  1. Evolutionary instability of symbiotic function in Bradyrhizobium japonicum.

    PubMed

    Sachs, Joel L; Russell, James E; Hollowell, Amanda C

    2011-01-01

    Bacterial mutualists are often acquired from the environment by eukaryotic hosts. However, both theory and empirical work suggest that this bacterial lifestyle is evolutionarily unstable. Bacterial evolution outside of the host is predicted to favor traits that promote an independent lifestyle in the environment at a cost to symbiotic function. Consistent with these predictions, environmentally-acquired bacterial mutualists often lose symbiotic function over evolutionary time. Here, we investigate the evolutionary erosion of symbiotic traits in Bradyrhizobium japonicum, a nodulating root symbiont of legumes. Building on a previous published phylogeny we infer loss events of nodulation capability in a natural population of Bradyrhizobium, potentially driven by mutation or deletion of symbiosis loci. Subsequently, we experimentally evolved representative strains from the symbiont population under host-free in vitro conditions to examine potential drivers of these loss events. Among Bradyrhizobium genotypes that evolved significant increases in fitness in vitro, two exhibited reduced symbiotic quality, but no experimentally evolved strain lost nodulation capability or evolved any fixed changes at six sequenced loci. Our results are consistent with trade-offs between symbiotic quality and fitness in a host free environment. However, the drivers of loss-of-nodulation events in natural Bradyrhizobium populations remain unknown.

  2. Succinate transport by free-living forms of Rhizobium japonicum.

    PubMed Central

    McAllister, C F; Lepo, J E

    1983-01-01

    We have demonstrated that the transport of succinate into the cells of Rhizobium japonicum strains USDA 110 and USDA 217 is severely inhibited by cyanide, azide, and 2,4-dinitrophenol, but not by arsenate. These results suggest an active mechanism of transport that is dependent on an energized membrane, but does not directly utilize ATP. The apparent Km for succinate was 3.8 microM for strain USDA 110 and 1.8 microM for strain USDA 217; maximal transport velocities were 1.5 and 3.3 nmol of succinate per min per mg of protein, respectively. The expression of the succinate uptake activity was inducible rather than constitutive, with succinate and structurally related compounds being the most effective inducers. The mechanism showed some specificity for succinate and similar organic acids; fumarate and L-malate were classical competitive inhibitors of the system. In general, the best competing compounds were also the best carbon substrates for induction of succinate uptake activity. EDTA inhibited the transport of succinate, implying a role for divalent cations in the system. When various divalent cations were used to reconstitute EDTA-inhibited activity, Ca2+ was most effective, followed by Mg2+, which restored activity at about half the efficiency of Ca2+. Growth media that were supplemented with increased Ca2+ concentration supported more rapid growth with succinate as the carbon substrate, and cells from such media showed higher specific activities of succinate transport. PMID:6402487

  3. Rhizobium japonicum mutants defective in symbiotic nitrogen fixation.

    PubMed Central

    Noel, K D; Stacey, G; Tandon, S R; Silver, L E; Brill, W J

    1982-01-01

    Rhizobium japonicum strains 3I1b110 and 61A76 were mutagenized to obtain 25 independently derived mutants that produced soybean nodules defective in nitrogen fixation, as assayed by acetylene reduction. The proteins of both the bacterial and the plant portions of the nodules were analyzed by two-dimensional polyacrylamide gel electrophoresis. All of the mutants had lower-than-normal levels of the nitrogenase components, and all but four contained a prominent bacteroid protein not observed in wild-type bacteroids. Experiments with bacteria grown ex planta suggested that this protein was derepressed by the absence of ammonia. Nitrogenase component II of one mutant was altered in isoelectric point. The soluble plant fraction of the nodules of seven mutants had very low levels of heme, yet the nodules of five of these seven mutants contained the polypeptide of leghemoglobin. Thus, the synthesis of the globin may not be coupled to the content of available heme in soybean nodules. The nodules of the other two of these seven mutants lacked not only leghemoglobin but most of the other normal plant and bacteroid proteins. Ultrastructural examination of nodules formed by these two mutants indicated normal ramification of infection threads but suggested a problem in subsequent survival of the bacteria and their release from the infection threads. Images PMID:6956566

  4. Isolation of a cytochrome aa3 gene from Bradyrhizobium japonicum

    PubMed Central

    O'Brian, Mark R.; Maier, Robert J.

    1987-01-01

    Bradyhizobium japonicum strain LO501 is a Tn5-induced mutant that does not express the terminal oxidase cytochrome aa3 (cytochrome-c oxidase, EC 1.9.3.1). Two and one-half kilobase pairs of LO501 genomic DNA that flanks the transposon was isolated and used as a hybridization probe to obtain the wild-type gene from a cosmid library. Two subcloned fragments from two of the isolated cosmids were ligated into broad host range vectors, and restriction maps of these fragments were generated. The resultant plasmids, pCA1 and pBL33, each contained DNA homologous to that mutated in strain LO501. The two plasmids were each introduced into strain LO501 by conjugal transfer, and it was found that pCA1, but not pBL33, complemented the oxidase mutant. The transconjugant strain LO501[pCA1] expressed wild-type levels of cytochrome aa3, as discerned spectrophotometrically, and had restored N,N,N′,N′-tetramethyl-p-phenylenediamine oxidase activity. Furthermore, the frequency of complementation of LO501 cells that received pCA1 by conjugation was 1.0, demonstrating that pCA1 complemented the mutant in trans. The results show that pCA1 contains the entire wild-type gene that was mutated in strain LO501, and this gene is required for cytochrome aa3 expression. Images PMID:16593835

  5. Evidence for at least six Hox clusters in the Japanese lamprey (Lethenteron japonicum).

    PubMed

    Mehta, Tarang K; Ravi, Vydianathan; Yamasaki, Shinichi; Lee, Alison P; Lian, Michelle M; Tay, Boon-Hui; Tohari, Sumanty; Yanai, Seiji; Tay, Alice; Brenner, Sydney; Venkatesh, Byrappa

    2013-10-01

    Cyclostomes, comprising jawless vertebrates such as lampreys and hagfishes, are the sister group of living jawed vertebrates (gnathostomes) and hence an important group for understanding the origin and diversity of vertebrates. In vertebrates and other metazoans, Hox genes determine cell fate along the anteroposterior axis of embryos and are implicated in driving morphological diversity. Invertebrates contain a single Hox cluster (either intact or fragmented), whereas elephant shark, coelacanth, and tetrapods contain four Hox clusters owing to two rounds of whole-genome duplication ("1R" and "2R") during early vertebrate evolution. By contrast, most teleost fishes contain up to eight Hox clusters because of an additional "teleost-specific" genome duplication event. By sequencing bacterial artificial chromosome (BAC) clones and the whole genome, here we provide evidence for at least six Hox clusters in the Japanese lamprey (Lethenteron japonicum). This suggests that the lamprey lineage has experienced an additional genome duplication after 1R and 2R. The relative age of lamprey and human paralogs supports this hypothesis. Compared with gnathostome Hox clusters, lamprey Hox clusters are unusually large. Several conserved noncoding elements (CNEs) were predicted in the Hox clusters of lamprey, elephant shark, and human. Transgenic zebrafish assay indicated the potential of CNEs to function as enhancers. Interestingly, CNEs in individual lamprey Hox clusters are frequently conserved in multiple Hox clusters in elephant shark and human, implying a many-to-many orthology relationship between lamprey and gnathostome Hox clusters. Such a relationship suggests that the first two rounds of genome duplication may have occurred independently in the lamprey and gnathostome lineages.

  6. Evidence for at least six Hox clusters in the Japanese lamprey (Lethenteron japonicum)

    PubMed Central

    Mehta, Tarang K.; Ravi, Vydianathan; Yamasaki, Shinichi; Lee, Alison P.; Lian, Michelle M.; Tay, Boon-Hui; Tohari, Sumanty; Yanai, Seiji; Tay, Alice; Brenner, Sydney; Venkatesh, Byrappa

    2013-01-01

    Cyclostomes, comprising jawless vertebrates such as lampreys and hagfishes, are the sister group of living jawed vertebrates (gnathostomes) and hence an important group for understanding the origin and diversity of vertebrates. In vertebrates and other metazoans, Hox genes determine cell fate along the anteroposterior axis of embryos and are implicated in driving morphological diversity. Invertebrates contain a single Hox cluster (either intact or fragmented), whereas elephant shark, coelacanth, and tetrapods contain four Hox clusters owing to two rounds of whole-genome duplication (“1R” and “2R”) during early vertebrate evolution. By contrast, most teleost fishes contain up to eight Hox clusters because of an additional “teleost-specific” genome duplication event. By sequencing bacterial artificial chromosome (BAC) clones and the whole genome, here we provide evidence for at least six Hox clusters in the Japanese lamprey (Lethenteron japonicum). This suggests that the lamprey lineage has experienced an additional genome duplication after 1R and 2R. The relative age of lamprey and human paralogs supports this hypothesis. Compared with gnathostome Hox clusters, lamprey Hox clusters are unusually large. Several conserved noncoding elements (CNEs) were predicted in the Hox clusters of lamprey, elephant shark, and human. Transgenic zebrafish assay indicated the potential of CNEs to function as enhancers. Interestingly, CNEs in individual lamprey Hox clusters are frequently conserved in multiple Hox clusters in elephant shark and human, implying a many-to-many orthology relationship between lamprey and gnathostome Hox clusters. Such a relationship suggests that the first two rounds of genome duplication may have occurred independently in the lamprey and gnathostome lineages. PMID:24043829

  7. Anti-Schistosoma IgG responses in Schistosoma haematobium single and concomitant infection with malaria parasites.

    PubMed

    Morenikeji, Olajumoke A; Adeleye, Olumide; Omoruyi, Ewean C; Oyeyemi, Oyetunde T

    2016-03-01

    Areas prone to schistosomiasis are also at risk of malaria transmission. The interaction between the causal agents of the two diseases could modulate immune responses tailored toward protecting or aggravating morbidity dynamics and impair Schistosoma diagnostic precision. This study aimed at assessing the effect of Plasmodium spp. in concomitant infection with Schistosoma haematobium in modulation of anti-Schistosoma IgG antibodies. The school-based cross-sectional study recruited a total of 322 children screened for S. haematobium and Plasmodium spp. Levels of IgG against S. haematobium-soluble egg antigen (SEA) in single S. haematobium/malaria parasites infection and co-infection of the two parasites in schoolchildren were determined. Data were analyzed using χ(2), Fisher's exact test, and Tukey's multiple comparison test analyses. The prevalence of single infection by S. haematobium, Plasmodium spp., and concurrent infection due to the two pathogens was 27.7, 41.0, and 9.3%, respectively (p < 0.0001). Anti-Schistosoma IgG production during co-infection of the two pathogens (1.950 ± 0.742 AU) was significantly higher than the value recorded for single malaria parasites' infection (1.402 ± 0.670 AU) (p < 0.01) but not in S. haematobium infection (1.591 ± 0.604 AU) (p > 0.05). The anti-Schistosoma IgG production in co-infection status was however dependent on the intensity of Plasmodium spp. with individuals having high intensity of malaria parasites recording lower anti-Schistosoma IgG. This study has implication for diagnosis of schistosomiasis where anti-Schistosoma IgG is used as an indicator of infection. Efforts should be made to control the two infections simultaneously in order not to undermine the efforts targeted toward the control of one.

  8. Decline in infection-related morbidities following drug-mediated reductions in the intensity of Schistosoma infection: A systematic review and meta-analysis.

    PubMed

    Andrade, Gisele; Bertsch, David J; Gazzinelli, Andrea; King, Charles H

    2017-02-01

    Since 1984, WHO has endorsed drug treatment to reduce Schistosoma infection and its consequent morbidity. Cross-sectional studies suggest pre-treatment correlation between infection intensity and risk for Schistosoma-related pathology. However, evidence also suggests that post-treatment reduction in intensity may not reverse morbidity because some morbidities occur at all levels of infection, and some reflect permanent tissue damage. The aim of this project was to systematically review evidence on drug-based control of schistosomiasis and to develop a quantitative estimate of the impact of post-treatment reductions in infection intensity on prevalence of infection-associated morbidity. This review was registered at inception with PROSPERO (CRD42015026080). Studies that evaluated morbidity before and after treatment were identified by online searches and searches of private archives. Post-treatment odds ratios or standardized mean differences were calculated for each outcome, and these were correlated to treatment-related egg count reduction ratios (ERRs) by meta-regression. A greater ERR correlated with greater reduction in odds of most morbidities. Random effects meta-analysis was used to derive summary estimates: after treatment of S. mansoni and S. japonicum, left-sided hepatomegaly was reduced by 54%, right-sided hepatomegaly by 47%, splenomegaly by 37%, periportal fibrosis by 52%, diarrhea by 53%, and blood in stools by 75%. For S. haematobium, hematuria was reduced by 92%, proteinuria by 90%, bladder lesions by 86%, and upper urinary tract lesions by 72%. There were no consistent changes in portal dilation or hemoglobin levels. In sub-group analysis, age, infection status, region, parasite species, and interval to follow-up were associated with meaningful differences in outcome. While there are challenges to implementing therapy for schistosomiasis, and praziquantel therapy is not fully curative, reductions in egg output are significantly correlated with

  9. Complete genome sequence of the mitochondrial DNA of the river lamprey, Lethenteron japonicum.

    PubMed

    Kawai, Yuri L; Yura, Kei; Shindo, Miyuki; Kusakabe, Rie; Hayashi, Keiko; Hata, Kenichiro; Nakabayashi, Kazuhiko; Okamura, Kohji

    2015-01-01

    Lampreys are eel-like jawless fishes evolutionarily positioned between invertebrates and vertebrates, and have been used as model organisms to explore vertebrate evolution. In this study we determined the complete genome sequence of the mitochondrial DNA of the Japanese river lamprey, Lethenteron japonicum, using next-generation sequencers. The sequence was 16,272 bp in length. The gene content and order were identical to those of the sea lamprey, Petromyzon marinus, which has been the reference among lamprey species. However, the sequence similarity was less than 90%, suggesting the need for the whole-genome sequencing of L. japonicum.

  10. Molecular identification of Schistosoma mattheei from feces of Kinda (Papio cynocephalus kindae) and grayfoot baboons (Papio ursinus griseipes) in Zambia.

    PubMed

    Weyher, Anna H; Phillips-Conroy, Jane E; Fischer, Kerstin; Weil, Gary J; Chansa, Wilbroad; Fischer, Peter U

    2010-02-01

    Terminal-spined Schistosoma sp. eggs were detected in several groups of baboons living in Kafue National Park in central Zambia. A total of 166 fecal samples was screened; egg prevalence overall ranged between 7% and 10%, while infection intensities were low. Formalin-fixed eggs had an average length of 144.5 microm and a breadth of 48.3 microm, but the s