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Sample records for human schistosoma japonicum

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. 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

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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.

  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. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. [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.

  19. 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.

  20. 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

  1. Quantitative aspects of the epidemiology of Schistosoma japonicum infection in a rural community of Luzon, Philippines

    PubMed Central

    1980-01-01

    In a rural community on the island of Luzon, Philippines, the overall prevalence of Schistosoma japonicum infection, based on stool examination performed by both a new modified quantitative thick smear and the merthiolate-iodine-formaldehyde concentration (MIFC) technique, was 49.5% in a total study population of 755 persons. Peak prevalence was observed in the 15-19-year age group, then decreased gradually. Although the total egg output was highest in the 15-19-year age group, individuals with high egg counts were found among all age groups. The prevalence and intensity of infection were higher in men than in women except in the 45-54-year age group. A small proportion (4.1%) of the study population (age range 6-53 years) excreted 50% of the eggs counted in this study. Liver and spleen enlargement were significantly associated with S. japonicum infection in all age groups. The frequency of a past history of dysentery and marked liver enlargement (≥ 5 cm) increased in parallel with increasing egg counts. Clustering of individuals with high egg counts in households was observed, but there was no correlation between geographical proximity of residence to potential transmission sites and household infection rates. An effective control strategy would be based on treatment of all infected persons in this endemic area rather than only a selected age group. PMID:6969135

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  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. 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

  1. 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.

  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. 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

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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.

  3. 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

  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. 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.

  6. 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.

  7. 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.

  8. 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).

  9. 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.

  10. 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

  11. 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

  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. 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.

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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.

  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. 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

  2. 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

  3. 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

  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. 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

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. [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.

  7. 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

  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. 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.

  10. 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

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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

  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. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. Hypericum japonicum Thunb. ex Murray: phytochemistry, pharmacology, quality control and pharmacokinetics of an important herbal medicine.

    PubMed

    Liu, Lin-Sheng; Liu, Meng-Hua; He, Jing-Yu

    2014-07-24

    Hypericum japonicum Thunb. ex Murray is mainly distributed throughout Asia, Oceania and North America and is used as an important herbal medicine. H. japonicum contains many valuable secondary metabolites, such as flavonoids, phloroglucinols and xanthones and has hepatoprotective, anti-tumor, antibacterial, antiviral, and antioxidant activities and effects on the cardiovascular system and immunity. Coupled with phytochemical and pharmacological research, a series of analytical methods have been developed to evaluate the quality of H. japonicum based on its bioactive components. A pharmacokinetics study involved the absorption of two main flavonoids of H. japonicum in rats. This review aims to present an up-to-date and comprehensive overview of the phytochemistry, pharmacology, quality control and pharmacokinetics of H. japonicum, which should be useful for the greater development of H. japonicum, especially in the development of new drugs and therapeutics for various diseases.

  14. 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.

  15. [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

  16. 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.

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  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. 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.

  9. 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

  10. 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).

  11. 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.

  12. 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

  13. 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.

  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. [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.

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. 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 schistosome species could not be unambiguously identified by size or morphology. We used molecular methods to definitively identify the parasite species. Parasite DNA was amplified from stools by polymerase chain reaction (PCR). Sequence analysis of fragments of the first internal transcribed spacer (ITS-1), mitochondrial 12S rDNA, NADH dehydrogenase subunit 6 (nad6), and cytochrome C oxidase subunit 1 (cox1) from 3 egg-positive samples revealed the presence of S. mattheei in these samples. This is the first molecular identification of S. mattheei from free-ranging baboons. Schistosoma mattheei is typically a parasite of bovids, but it can also infect humans. Schistosoma mattheei in baboons in Zambia may affect other wildlife species and humans that live in close proximity to baboons.

  2. Lethal and sublethal effects of thiamethoxam on the whitefly predator Serangium japonicum (Coleoptera: Coccinellidae) through different exposure routes.

    PubMed

    Yao, Feng-Luan; Zheng, Yu; Zhao, Jian-Wei; Desneux, Nicolas; He, Yu-Xian; Weng, Qi-Yong

    2015-06-01

    Given expectations for a booming usage of thiamethoxam and increasing availability of the promising biological agent Serangium japonicum for the control of Bemisia tabaci in China, an evaluation of their compatibility is crucial for integrated pest management (IPM). This study examined the lethal and sublethal effects of thiamethoxam on S. japonicum through three exposure routes. An acute toxicity bioassay showed that LC50 values of thiamethoxam for S. japonicum through residue contact, egg-dip, and systemic treatment were 6.65, 4.37, and 2.43 mg AI L(-1), respectively. The prey consumption of S. japonicum given different densities of B. tabaci eggs under control, discontinuous, egg-dip and systemic exposure scenarios showed a good fit to a Type II functional response. Predation of S. japonicum was most affected under systemic exposure, followed by egg-dip, and discontinuous, which was only slightly affected. In all cases tested, however, predators recovered their predation capacity rapidly, either after 24h of exposure or 24h after the end of exposure. Thiamethoxam was highly toxic to S. japonicum regardless of exposure routes. Sublethal effects of thiamethoxam applied systemically or foliar both impaired the biological control of S. japonicum on B. tabaci. Therefore, thiamethoxam should be used with caution in IPM of B. tabaci.

  3. Developmental Regulation of Genes Encoding Universal Stress Proteins in Schistosoma mansoni

    PubMed Central

    Isokpehi, Raphael D.; Mahmud, Ousman; Mbah, Andreas N.; Simmons, Shaneka S.; Avelar, Lívia; Rajnarayanan, Rajendram V.; Udensi, Udensi K.; Ayensu, Wellington K.; Cohly, Hari H.; Brown, Shyretha D.; Dates, Centdrika R.; Hentz, Sonya D.; Hughes, Shawntae J.; Smith-McInnis, Dominique R.; Patterson, Carvey O.; Sims, Jennifer N.; Turner, Kelisha T.; Williams, Baraka S.; Johnson, Matilda O.; Adubi, Taiwo; Mbuh, Judith V.; Anumudu, Chiaka I.; Adeoye, Grace O.; Thomas, Bolaji N.; Nashiru, Oyekanmi; Oliveira, Guilherme

    2011-01-01

    The draft nuclear genome sequence of the snail-transmitted, dimorphic, parasitic, platyhelminth Schistosoma mansoni revealed eight genes encoding proteins that contain the Universal Stress Protein (USP) domain. Schistosoma mansoni is a causative agent of human schistosomiasis, a severe and debilitating Neglected Tropical Disease (NTD) of poverty, which is endemic in at least 76 countries. The availability of the genome sequences of Schistosoma species presents opportunities for bioinformatics and genomics analyses of associated gene families that could be targets for understanding schistosomiasis ecology, intervention, prevention and control. Proteins with the USP domain are known to provide bacteria, archaea, fungi, protists and plants with the ability to respond to diverse environmental stresses. In this research investigation, the functional annotations of the USP genes and predicted nucleotide and protein sequences were initially verified. Subsequently, sequence clusters and distinctive features of the sequences were determined. A total of twelve ligand binding sites were predicted based on alignment to the ATP-binding universal stress protein from Methanocaldococcus jannaschii. In addition, six USP sequences showed the presence of ATP-binding motif residues indicating that they may be regulated by ATP. Public domain gene expression data and RT-PCR assays confirmed that all the S. mansoni USP genes were transcribed in at least one of the developmental life cycle stages of the helminth. Six of these genes were up-regulated in the miracidium, a free-swimming stage that is critical for transmission to the snail intermediate host. It is possible that during the intra-snail stages, S. mansoni gene transcripts for universal stress proteins are low abundant and are induced to perform specialized functions triggered by environmental stressors such as oxidative stress due to hydrogen peroxide that is present in the snail hemocytes. This report serves to catalyze the

  4. Morbidity markers for Schistosoma haematobium infection.

    PubMed

    Vennervald, B J; Reimert, C M; Ouma, J H; Kilama, W L; Deelder, A M; Hatz, C

    1994-01-01

    A description is given of a field study design, including pretreatment and short and long-term posttreatment measurements, which is conducted as a case-control study among school children in Kaloleni District, Kenya, and Kilosa District, Tanzania, including 500 school children from each endemic setting. The aim of the study is to evaluate eosinophil cationic protein (ECP) in urine as a marker for Schistosoma haematobium morbidity by comparing levels of ECP in urine with S. haematobium egg counts in urine, level of excreted S. haematobium egg antigen in urine, microhaematuria and urinary tract pathology assessed by ultrasonography. Initial results have been promising and are now subject to an extensive evaluation. Strong training components and transfer of technology are included in the project, thus contributing to the strengthening of the research capacity of the collaborating African institutions. Simple non-invasive assays for ECP and excreted S. haematobium egg antigen could provide new tools for evaluation of chemotherapy effects and morbidity in urinary schistosomiasis, helping to understand the dynamic process of posttreatment resolution and reappearance of pathological changes.

  5. Evidence for ryanodine receptors in Schistosoma mansoni.

    PubMed

    Silva, C L; Cunha, V M; Mendonça-Silva, D L; Noël, F

    1998-10-15

    The present study investigated the presence of ryanodine receptors in the trematode Schistosoma mansoni. [3H]Ryanodine specific binding sites were found in the four subcellular fractions of S. mansoni; however, more binding sites were recovered in the heterogeneous fraction P1 and the microsomal fraction P4, as was thapsigargin-sensitive (Ca2+-Mg2+)ATPase activity, marking the sarco/endoplasmic reticulum calcium ATPase (SERCA) pumps. This binding had an equilibrium dissociation constant (Kd) in the nanomolar range, an apparent maximal number of receptors (Bmax) of about 80 fmol/mg of protein, and was modulated by ions (Ca2+, Mg2+) and some pharmacological tools such as caffeine. Ryanodine was able to accelerate the rate of 45Ca2+ release from actively loaded vesicles, and also to induce a transient contraction of the whole worm. We conclude that ryanodine-sensitive Ca2+ release channels are present in S. mansoni, with properties very similar to the ones present in higher animals.

  6. Control of calcium homeostasis in Schistosoma mansoni.

    PubMed

    Noël, F; Cunha, V M; Silva, C L; Mendonça-Silva, D L

    2001-01-01

    Calcium signalling is fundamental for muscular contractility of Schistosoma mansoni. We have previously described the presence of transport ATPases (Na+,K+-ATPase and (Ca2+-Mg2+)-ATPase) and calcium channels (ryanodine receptors - RyR) involved in control of calcium homeostasis in this worm. Here we briefly review the main technics (ATPase activity, binding with specific radioligands, fluxes of 45Ca2+ and whole worm contractions) and results obtained in order to compare the distribution patterns of these proteins: thapsigargin-sensitive (Ca2+-Mg2+)-ATPase activity and RyR co-purified in P1 and P4 fractions mainly, which is compatible with a sarcoplasmic reticulum localization, while basal ATPase (along with Na+,K+-ATPase) and thapsigargin-resistant (Ca2+-Mg2+)-ATPase have a distinct distribution, indicative of their plasma membrane localization. Finally we attempt to integrate these contributions with data from other groups in order to propose the first synoptic model for control of calcium homeostasis in S. mansoni.

  7. The complete denitrification pathway of the symbiotic, nitrogen-fixing bacterium Bradyrhizobium japonicum.

    PubMed

    Bedmar, E J; Robles, E F; Delgado, M J

    2005-02-01

    Denitrification is an alternative form of respiration in which bacteria sequentially reduce nitrate or nitrite to nitrogen gas by the intermediates nitric oxide and nitrous oxide when oxygen concentrations are limiting. In Bradyrhizobium japonicum, the N(2)-fixing microsymbiont of soya beans, denitrification depends on the napEDABC, nirK, norCBQD, and nosRZDFYLX gene clusters encoding nitrate-, nitrite-, nitric oxide- and nitrous oxide-reductase respectively. Mutational analysis of the B. japonicum nap genes has demonstrated that the periplasmic nitrate reductase is the only enzyme responsible for nitrate respiration in this bacterium. Regulatory studies using transcriptional lacZ fusions to the nirK, norCBQD and nosRZDFYLX promoter region indicated that microaerobic induction of these promoters is dependent on the fixLJ and fixK(2) genes whose products form the FixLJ-FixK(2) regulatory cascade. Besides FixK(2), another protein, nitrite and nitric oxide respiratory regulator, has been shown to be required for N-oxide regulation of the B. japonicum nirK and norCBQD genes. Thus nitrite and nitric oxide respiratory regulator adds to the FixLJ-FixK(2) cascade an additional control level which integrates the N-oxide signal that is critical for maximal induction of the B. japonicum denitrification genes. However, the identity of the signalling molecule and the sensing mechanism remains unknown.

  8. Complete Genome Sequence of Bradyrhizobium japonicum J5, Isolated from a Soybean Nodule in Hokkaido, Japan

    PubMed Central

    Kanehara, Kazuma

    2017-01-01

    ABSTRACT Soybean bradyrhizobia form root nodules on soybean plants and symbiotically fix N2. Strain J5 is phylogenetically far from well-known representatives within the Bradyrhizobium japonicum linage. The complete genome showed the largest single chromosomal (10.1 Mb) and symbiosis island (998 kb) among complete genomes of soybean bradyrhizobia. PMID:28183772

  9. Characterization of a Functional Role of the Bradyrhizobium japonicum Isocitrate Lyase in Desiccation Tolerance.

    PubMed

    Jeon, Jeong-Min; Lee, Hae-In; Sadowsky, Michael J; Sugawara, Masayuki; Chang, Woo-Suk

    2015-07-22

    Bradyrhizobium japonicum is a nitrogen-fixing symbiont of soybean. In previous studies, transcriptomic profiling of B. japonicum USDA110, grown under various environmental conditions, revealed the highly induced gene aceA, encoding isocitrate lyase (ICL). The ICL catalyzes the conversion of isocitrate to succinate and glyoxylate in the glyoxylate bypass of the TCA cycle. Here, we evaluated the functional role of B. japonicum ICL under desiccation-induced stress conditions. We purified AceA (molecular mass = 65 kDa) from B. japonicum USDA110, using a His-tag and Ni-NTA column approach, and confirmed its ICL enzyme activity. The aceA mutant showed higher sensitivity to desiccation stress (27% relative humidity (RH)), compared to the wild type. ICL activity of the wild type strain increased approximately 2.5-fold upon exposure to 27% RH for 24 h. The aceA mutant also showed an increased susceptibility to salt stress. Gene expression analysis of aceA using qRT-PCR revealed a 148-fold induction by desiccation, while other genes involved in the glyoxylate pathway were not differentially expressed in this condition. Transcriptome analyses revealed that stress-related genes, such as chaperones, were upregulated in the wild-type under desiccating conditions, even though fold induction was not dramatic (ca. 1.5-2.5-fold).

  10. Plant recognition of Bradyrhizobium japonicum nod factors. Final report, September 15, 1992--March 14, 1997

    SciTech Connect

    Stacey, G.

    1998-01-01

    This grant had three objectives: (1) isolate and identify the unique nod factor metabolites made by different wild-type B. japonicum strains; (2) investigate the biological activity of these unique nod factors, especially as it relates to host range; and (3) initiate studies to define the mechanism of plant recognition of the nod factors. This report summarizes the results of this research.

  11. Coordinate expression of hydrogenase and ribulose bisphosphate carboxylase in Rhizobium japonicum Hupc mutants.

    PubMed Central

    Merberg, D; Maier, R J

    1984-01-01

    In contrast to the wild type, H2 uptake-constitutive mutants of Rhizobium japonicum expressed both hydrogenase and ribulose bisphosphate carboxylase activities when grown heterotrophically. However, as bacteroids from soybean root nodules, the H2 uptake-constitutive mutants, like the wild type, did not express ribulose bisphosphate carboxylase activity. PMID:6384199

  12. A genetic locus essential for formate-dependent growth of Bradyrhizobium japonicum.

    PubMed Central

    McClung, C R; Chelm, B K

    1987-01-01

    A genetic locus essential for the formate-dependent growth of Bradyrhizobium japonicum was isolated by complementation of ethyl methanesulfonate-induced mutants with a cosmid gene library of B. japonicum DNA. Three related cosmids containing 18.7 kilobase pairs of B. japonicum DNA in common were identified as being able to restore formate-dependent growth capability to mutants lacking either ribulosebisphosphate carboxylase or both ribulosebisphosphate carboxylase and phosphoribulokinase activities. To further localize the complementing gene(s), a series of four deletions spanning a total of 16.1 kilobase pairs were introduced into the B. japonicum chromosome. Each resulting deletion mutant lacked formate dehydrogenase activity and lacked ribulosebisphosphate carboxylase activity and immunologically detectable protein. Three of the four also lacked phosphoribulokinase activity. Two other mutants in which the deletion-bearing recombinant plasmid had integrated into the chromosome also lacked ribulosebisphosphate carboxylase activity and protein and phosphoribulokinase activities. The genetic locus defined by these mutants could contain the structural genes for these enzymes or a regulatory gene(s) controlling their expression or both. Images PMID:3036781

  13. CD8α¯ DC is the major DC subset which mediates inhibition of allergic responses by Schistosoma infection.

    PubMed

    Liu, J-Y; Lu, P; Hu, L-Z; Shen, Y-J; Zhu, Y-J; Ren, J-L; Ji, W-H; Zhang, X-Z; Wu, Z-Q; Yang, X-Z; Yang, J; Li, L-Y; Yang, X; Liu, P-M

    2014-12-01

    Our and others' previous studies have shown that Schistosoma japonicum (SJ) infection can inhibit allergic reactions. We recently reported that DCs played an important role in SJ infection-mediated inhibition of allergy, which was associated with enhanced IL-10 and T regulatory cell responses. Here, we further compared the role of CD8α(+) DC and CD8α(-) DC subsets for the inhibitory effect. We sorted CD8α(+) DC (SJCD8α(+) DC) and CD8α(-) DC (SJCD8α(-) DC) from SJ-infected mice and tested their ability to modulate allergic responses in vivo. The data showed that the adoptive transfer of SJCD8α(-) DC was much more efficient than SJCD8α(+) DC for the suppression of allergic airway eosinophilia, mucus overproduction, antigen-specific IgE responses, and Th2 cytokines (IL-4 and IL-5). More importantly, we found that the transfer of SJCD8α(-) DC, but not SJCD8α(+) DC, significantly increased IL-10 and TGF-β production following OVA exposure. As control, the transfer of DC subsets from naïve mice had no significant effect on allergic inflammation. In addition, SJCD8α-DC expressed significantly higher IL-10 but lower IL-12, CD80 and CD86 than SJCD8α(+) DC, fitting a tolerogenic phenotype. The results suggest that CD8α(-) DC is the predominant DC subset which is involved in the parasitic infection-mediated inhibition of allergic inflammation and possibly through enhancing immunomodulatory cytokine (IL-10 and TGF-β) production.

  14. Crystal Structure of Schistosoma mansoni Adenosine Phosphorylase/5’-Methylthioadenosine Phosphorylase and Its Importance on Adenosine Salvage Pathway

    PubMed Central

    Torini, Juliana Roberta; Brandão-Neto, José; DeMarco, Ricardo; Pereira, Humberto D'Muniz

    2016-01-01

    Schistosoma mansoni do not have de novo purine pathways and rely on purine salvage for their purine supply. It has been demonstrated that, unlike humans, the S. mansoni is able to produce adenine directly from adenosine, although the enzyme responsible for this activity was unknown. In the present work we show that S. mansoni 5´-deoxy-5´-methylthioadenosine phosphorylase (MTAP, E.C. 2.4.2.28) is capable of use adenosine as a substrate to the production of adenine. Through kinetics assays, we show that the Schistosoma mansoni MTAP (SmMTAP), unlike the mammalian MTAP, uses adenosine substrate with the same efficiency as MTA phosphorolysis, which suggests that this enzyme is part of the purine pathway salvage in S. mansoni and could be a promising target for anti-schistosoma therapies. Here, we present 13 SmMTAP structures from the wild type (WT), including three single and one double mutant, and generate a solid structural framework for structure description. These crystal structures of SmMTAP reveal that the active site contains three substitutions within and near the active site when compared to it mammalian counterpart, thus opening up the possibility of developing specific inhibitors to the parasite MTAP. The structural and kinetic data for 5 substrates reveal the structural basis for this interaction, providing substract for inteligent design of new compounds for block this enzyme activity. PMID:27935959

  15. Long-Term Frozen Storage of Urine Samples: A Trouble to Get PCR Results in Schistosoma spp. DNA Detection?

    PubMed Central

    Fernández-Soto, Pedro; Velasco Tirado, Virginia; Carranza Rodríguez, Cristina; Pérez-Arellano, José Luis; Muro, Antonio

    2013-01-01

    Background Human schistosomiasis remains a serious worldwide public health problem. At present, a sensitive and specific assay for routine diagnosis of schistosome infection is not yet available. The potential for detecting schistosome-derived DNA by PCR-based methods in human clinical samples is currently being investigated as a diagnostic tool with potential application in routine schistosomiasis diagnosis. Collection of diagnostic samples such as stool or blood is usually difficult in some populations. However, urine is a biological sample that can be collected in a non-invasive method, easy to get from people of all ages and easy in management, but as a sample for PCR diagnosis is still not widely used. This could be due to the high variability in the reported efficiency of detection as a result of the high variation in urine samples’ storage or conditions for handling and DNA preservation and extraction methods. Methodology/Principal Findings We evaluate different commercial DNA extraction methods from a series of long-term frozen storage human urine samples from patients with parasitological confirmed schistosomiasis in order to assess the PCR effectiveness for Schistosoma spp. detection. Patientś urine samples were frozen for 18 months up to 7 years until use. Results were compared with those obtained in PCR assays using fresh healthy human urine artificially contaminated with Schistosoma mansoni DNA and urine samples from mice experimentally infected with S. mansoni cercariae stored frozen for at least 12 months before use. PCR results in fresh human artificial urine samples using different DNA based extraction methods were much more effective than those obtained when long-term frozen human urine samples were used as the source of DNA template. Conclusions/Significance Long-term frozen human urine samples are probably not a good source for DNA extraction for use as a template in PCR detection of Schistosoma spp., regardless of the DNA method of

  16. The nir, nor, and nos denitrification genes are dispersed over the Bradyrhizobium japonicum chromosome.

    PubMed

    Mesa, S; Göttfert, M; Bedmar, E J

    2001-07-01

    Cleavage of genomic DNA from Bradyrhizobium japonicum strain 3I1b110 by the restriction enzymes PmeI, PacI, and SwaI has been used together with pulsed-field gel electrophoresis and Southern hybridization to locate the nirK, norCBQD, and nosRZDFYLX denitrification genes on the chromosomal map of B. japonicum strain 110spc4. Mutant strains GRK13, GRC131, and GRZ25 were obtained by insertion of plasmid pUC4-KIXX-aphII-PSP, which carries recognition sites for the enzymes PacI, PmeI and SwaI, into the B. japonicum 3I1b110 nirK, norC and nosZ genes, respectively. Restriction of strain 3I1b110 genomic DNA with PacI, PmeI and SwaI yielded three, five and nine fragments, respectively. Pulsed-field gel electrophoresis of restricted mutant DNAs resulted in an altered fragment pattern that allowed determination of the position of the selected genes. Complementary mapping data were obtained by hybridization using digoxigenin-labeled B. japonicum 3I1b110 nirK, norBQD and nosZD as gene probes. The nirK, norCBQD and nosRZDFYLX genes were located close to the groEL(2), cycH and cycVWX genes, respectively, on the strain 110spc4 genetic map. In contrast to other denitrifiers, B. japonicum 3I1b110 denitrification genes were dispersed over the entire chromosome.

  17. NifA is required for maximal expression of denitrification genes in Bradyrhizobium japonicum.

    PubMed

    Bueno, Emilio; Mesa, Socorro; Sanchez, Cristina; Bedmar, Eulogio J; Delgado, María J

    2010-02-01

    In Bradyrhizobium japonicum the napEDABC, nirK, norCBQD and nosRZDYFLX genes, which encode reductases for nitrate, nitrite, nitric oxide and nitrous oxide, respectively, are required for denitrification. Microaerobic induction of these genes depends on fixLJ and fixK2, whose products form the FixLJ-FixK2 regulatory cascade. In B. japonicum, a second oxygen-responsive regulatory cascade mediated by the nitrogen fixation regulatory protein, NifA, has been described. In this study, we show that disruption of nifA caused a growth defect in B. japonicum cells, when grown under denitrifying conditions, and decreased activity of periplasmic nitrate and nitrite reductase enzymes was also observed. Furthermore, expression of napE-lacZ, nirK-lacZ or norC-lacZ transcriptional fusions, as well as levels of nirK transcripts were significantly reduced in the nifA mutant after incubation under nitrate-respiring conditions. Haem c staining analyses revealed that NifA is required for full synthesis of the NapC and NorC proteins, which are required for denitrification. A B. japonicum rpoN1/2 mutant, lacking both copies of the gene encoding the alternative sigma factor sigma54, was able to grow anaerobically with nitrate as terminal electron acceptor and showed wild-type levels of nitrate and nitrite reductase activities. We propose that the nitrogen fixation regulatory protein, NifA, is involved in the maximal expression of the denitrification genes in B. japonicum. This influence is independent of sigma54.

  18. De novo transcriptome assembly of a fern, Lygodium japonicum, and a web resource database, Ljtrans DB.

    PubMed

    Aya, Koichiro; Kobayashi, Masaaki; Tanaka, Junmu; Ohyanagi, Hajime; Suzuki, Takayuki; Yano, Kenji; Takano, Tomoyuki; Yano, Kentaro; Matsuoka, Makoto

    2015-01-01

    During plant evolution, ferns originally evolved as a major vascular plant with a distinctive life cycle in which the haploid and diploid generations are completely separated. However, the low level of genetic resources has limited studies of their physiological events, as well as hindering research on the evolutionary history of land plants. In this study, to identify a comprehensive catalog of transcripts and characterize their expression traits in the fern Lygodium japonicum, nine different RNA samples isolated from prothalli, trophophylls, rhizomes and sporophylls were sequenced using Roche 454 GS-FLX and Illumina HiSeq sequencers. The hybrid assembly of the high-quality 454 GS-FLX and Illumina HiSeq reads generated a set of 37,830 isoforms with an average length of 1,444 bp. Using four open reading frame (ORF) predictors, 38,142 representative ORFs were identified from a total of 37,830 transcript isoforms and 95 contigs, which were annotated by searching against several public databases. Furthermore, an orthoMCL analysis using the protein sequences of L. japonicum and five model plants revealed various sets of lineage-specific genes, including those detected among land plant lineages and those detected in only L. japonicum. We have also examined the expression patterns of all contigs/isoforms, along with the life cycle of L. japonicum, and identified the tissue-specific transcripts using statistical expression analyses. Finally, we developed a public web resource, the L. japonicum transcriptome database at http://bioinf.mind.meiji.ac.jp/kanikusa/, which provides important opportunities to accelerate molecular research in ferns.

  19. Possible eggshell protein gene from Schistosoma mansoni.

    PubMed

    Johnson, K S; Taylor, D W; Cordingley, J S

    1987-01-02

    We have identified and sequenced a cDNA clone of a mRNA found only in mature female schistosomes. This mRNA is not detectably synthesized by female worms from single sex infections (unisexual females), by males or by the developing miracidia in the eggs. The clone hybridises to a highly abundant polyadenylated mRNA of approximately 1500 nucleotides. The nucleotide sequence of the clone predicts a polypeptide comprising two repetitive regions. A pentapeptide repeat with the consensus sequence Gly-Tyr-Asp-Lys-Tyr, and a region rich in histidine residues. Hybrid selected mRNA translated in vitro with [3H]tyrosine as labelled amino acid yields a polypeptide of 48 kDa (p48) that corresponds to the major [3H]tyrosine labelled translation product of female worm total mRNA. p48 does not label with [35S]methionine and is absent from the translation products of male and unisexual female mRNAs. The amino acid sequence of p48 has significant homologies to silk moth chorion proteins and we suggest that it is one of the major components of the schistosome eggshell probably accounting for the high level of [3H]tyrosine incorporation into the vitellaria of Schistosoma mansoni. The tyrosine content of the polypeptide suggests that it may play a role in phenol oxidase mediated cross-linking of the schistosome eggshell and in support of this we find that mushroom phenol oxidase will cause the specific cross-linking of p48 in in vitro translation products.

  20. Proteasome stress responses in Schistosoma mansoni.

    PubMed

    de Paula, Renato Graciano; de Magalhães Ornelas, Alice Maria; Morais, Enyara Rezende; de Souza Gomes, Matheus; de Paula Aguiar, Daniela; Magalhães, Lizandra Guidi; Rodrigues, Vanderlei

    2015-05-01

    The proteasome proteolytic system is the major ATP-dependent protease in eukaryotic cells responsible for intracellular protein turnover. Schistosoma mansoni has been reported to contain an ubiquitin-proteasome proteolytic pathway, and many studies have suggested a biological role of proteasomes in the development of this parasite. Additionally, evidence has suggested diversity in proteasome composition under several cellular conditions, and this might contribute to the regulation of its function in this parasite. The proteasomal system has been considered important to support the protein homeostasis during cellular stress. In this study, we described in vitro effects of oxidative stress, heat shock, and chemical stress on S. mansoni adults. Our findings showed that chemical stress induced with curcumin, IBMX, and MG132 modified the gene expression of the proteasomal enzymes SmHul5 and SmUbp6. Likewise, the expression of these genes was upregulated during oxidative stress and heat shock. Analyses of the S. mansoni life cycle showed differential gene expression in sporocysts, schistosomulae, and miracidia. These results suggested that proteasome accessory proteins participate in stress response during the parasite development. The expression level of SmHul5 and SmUbp6 was decreased by 16-fold and 9-fold, respectively, by the chemical stress induced with IBMX, which suggests proteasome disassembly. On the other hand, curcumin, MG132, oxidative stress, and heat shock increased the expression of these genes. Furthermore, the gene expression of maturation proteasome protein (SmPOMP) was increased in stress conditions induced by curcumin, MG132, and H₂O₂, which could be related to the synthesis of new proteasomes. S. mansoni adult worms were found to utilize similar mechanisms to respond to different conditions of stress. Our results demonstrated that oxidative stress, heat shock, and chemical stress modified the expression profile of genes related to the ubiquitin

  1. Efficient Ligation of the Schistosoma Hammerhead Ribozyme †

    PubMed Central

    Canny, Marella D.; Jucker, Fiona M.; Pardi, Arthur

    2011-01-01

    The hammerhead ribozyme from Schistosoma mansoni is the best characterized of the natural hammerhead ribozymes. Biophysical, biochemical, and structural studies have shown that the formation of the loop-loop tertiary interaction between stems I and II alters the global folding, cleavage kinetics, and conformation of the catalytic core of this hammerhead, leading to a ribozyme that is readily cleaved under physiological conditions. This study investigates the ligation kinetics and the internal equilibrium between cleavage and ligation for the Schistosoma hammerhead. Single turnover kinetic studies on a construct where the ribozyme cleaves and ligates substrate(s) in trans showed up to 23% ligation when starting from fully cleaved products. This was achieved by a ~2,000-fold increase in the rate of ligation compared to a minimal hammerhead without the loop-loop tertiary interaction, yielding an internal equilibrium that ranges from 2–3 at physiological Mg2+ ion concentrations (0.1 –1 mM). Thus, the natural Schistosoma hammerhead ribozyme is almost as efficient at ligation as it is at cleavage. The results here are consistent with a model where formation of the loop-loop tertiary interaction leads to a higher population of catalytically active molecules, and where formation of this tertiary interaction has a much larger effect on the ligation than the cleavage activity of the Schistosoma hammerhead ribozyme. PMID:17319693

  2. Assessment of Trichogramma japonicum and T. chilonis as Potential Biological Control Agents of Yellow Stem Borer in Rice.

    PubMed

    Tang, Rui; Babendreier, Dirk; Zhang, Feng; Kang, Min; Song, Kai; Hou, Mao-Lin

    2017-02-08

    Two species of Trichogramma wasps were assessed for their effectiveness against yellow stem borer Scirpophaga incertulas. A laboratory cage test with T. japonicum and T. chilonis showed that both species parasitized yellow stem borer egg masses at 60.0% ± 9.13% and 40.7% ± 7.11%, respectively, with egg parasitism rates of 15.8% ± 22.2% for T. japonicum and 2.8% ± 5.0% for T. chilonis. Once the host eggs were parasitized, emergence rates were high for both species (95.7% ± 0.12% for T. japonicum and 100% for T. chilonis). In paddy field trials, the two Trichogramma species were released at three densities (50,000/ha, 100,000/ha and 200,000/ha) in Southwestern China. Egg mass parasitism was 9% ± 7.7% for T. japonicum and 15% ± 14.1% for T. chilonis, and again only a relatively small fraction of eggs was successfully parasitized. No clear conclusion could be drawn on the most efficient release rate as no significant differences were found among the three release rates. A comparison of field-collected T. japonicum with T. japonicum and T. chilonis mass reared on Corcyra cephalonica showed significantly larger body size and ovipositor length in field-collected wasps, suggesting potentially higher effectiveness on yellow stem borer eggs after at least one generation on the target host. Factors contributing to the low field parasitism rates are discussed.

  3. Assessment of Trichogramma japonicum and T. chilonis as Potential Biological Control Agents of Yellow Stem Borer in Rice

    PubMed Central

    Tang, Rui; Babendreier, Dirk; Zhang, Feng; Kang, Min; Song, Kai; Hou, Mao-Lin

    2017-01-01

    Two species of Trichogramma wasps were assessed for their effectiveness against yellow stem borer Scirpophaga incertulas. A laboratory cage test with T. japonicum and T. chilonis showed that both species parasitized yellow stem borer egg masses at 60.0% ± 9.13% and 40.7% ± 7.11%, respectively, with egg parasitism rates of 15.8% ± 22.2% for T. japonicum and 2.8% ± 5.0% for T. chilonis. Once the host eggs were parasitized, emergence rates were high for both species (95.7% ± 0.12% for T. japonicum and 100% for T. chilonis). In paddy field trials, the two Trichogramma species were released at three densities (50,000/ha, 100,000/ha and 200,000/ha) in Southwestern China. Egg mass parasitism was 9% ± 7.7% for T. japonicum and 15% ± 14.1% for T. chilonis, and again only a relatively small fraction of eggs was successfully parasitized. No clear conclusion could be drawn on the most efficient release rate as no significant differences were found among the three release rates. A comparison of field-collected T. japonicum with T. japonicum and T. chilonis mass reared on Corcyra cephalonica showed significantly larger body size and ovipositor length in field-collected wasps, suggesting potentially higher effectiveness on yellow stem borer eggs after at least one generation on the target host. Factors contributing to the low field parasitism rates are discussed. PMID:28208706

  4. Lack of glyphosate resistance gene transfer from Roundup Ready soybean to Bradyrhizobium japonicum under field and laboratory conditions.

    PubMed

    Isaza, Laura Arango; Opelt, Katja; Wagner, Tobias; Mattes, Elke; Bieber, Evi; Hatley, Elwood O; Roth, Greg; Sanjuán, Juan; Fischer, Hans-Martin; Sandermann, Heinrich; Hartmann, Anton; Ernst, Dieter

    2011-01-01

    A field study was conducted at the Russell E. Larson Agricultural Research Center to determine the effect of transgenic glyphosate-resistant soybean in combination with herbicide (Roundup) application on its endosymbiont Bradyrhizobium japonicum. DNA of bacteroids from isolated nodules was analysed for the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (CP4-EPSPS) DNA sequence using polymerase chain reaction (PCR). To further assess the likelihood that the EPSPS gene may be transferred from the Roundup Ready (RR) soybean to B. japonicum, we have examined the natural transformation efficiency of B. japonicum strain 110spc4. Analyses of nodules showed the presence of the transgenic EPSPS DNA sequence. In bacteroids that were isolated from nodules of transgenic soybean plants and then cultivated in the presence of glyphosate this sequence could not be detected. This indicates that no stable horizontal gene transfer (HGT) of the EPSPS gene had occurred under field conditions. Under laboratory conditions, no natural transformation was detected in B. japonicum strain 110spc4 in the presence of various amounts of recombinant plasmid DNA. Our results indicate that no natural competence state exists in B. japonicum 110spc4. Results from field and laboratory studies indicate the lack of functional transfer of the CP4-EPSPS gene from glyphosate-tolerant soybean treated with glyphosate to root-associated B. japonicum.

  5. Construction and characterization of a Schistosoma mansoni bacterial artificial chromosome library.

    PubMed

    Le Paslier, M C; Pierce, R J; Merlin, F; Hirai, H; Wu, W; Williams, D L; Johnston, D; LoVerde, P T; Le Paslier, D

    2000-04-15

    A bacterial artificial chromosome (BAC) library has been established from genomic DNA isolated from the trematode parasite of human, Schistosoma mansoni. This library consists of more than 21,000 recombinant clones carrying inserts in the pBeloBAC11 vector. The mean insert size was 100 kb, representing an approximate 7.95-fold genome coverage. Library screening with eight chromosome-specific or single-copy gene probes yielded between 1 and 9 positive clones, and none of those tested was absent from the library. End sequences were obtained for 93 randomly selected clones, and 37 showed sequence identity to S. mansoni sequences (ESTs, genes, or repetitive sequences). A preliminary analysis by fluorescence in situ hybridization localized 8 clones on schistosome chromosomes 1 (2 clones), 2, 3, 5, Z, and W (3 clones). This library provides a new resource for the physical mapping and sequencing of the genome of this important human pathogen.

  6. Green synthesis of silver nanoparticles using Ganoderma neo-japonicum Imazeki: a potential cytotoxic agent against breast cancer cells

    PubMed Central

    Gurunathan, Sangiliyandi; Raman, Jegadeesh; Malek, Sri Nurestri Abd; John, Priscilla A; Vikineswary, Sabaratnam

    2013-01-01

    Background Silver nanoparticles (AgNPs) are an important class of nanomaterial for a wide range of industrial and biomedical applications. AgNPs have been used as antimicrobial and disinfectant agents due their detrimental effect on target cells. The aim of our study was to determine the cytotoxic effects of biologically synthesized AgNPs using hot aqueous extracts of the mycelia of Ganoderma neo-japonicum Imazeki on MDA-MB-231 human breast cancer cells. Methods We developed a green method for the synthesis of water-soluble AgNPs by treating silver ions with hot aqueous extract of the mycelia of G. neo-japonicum. The formation of AgNPs was characterized by ultraviolet-visible absorption spectroscopy, X-ray diffraction, dynamic light scattering, and transmission electron microscopy. Furthermore, the toxicity of synthesized AgNPs was evaluated using a series of assays: such as cell viability, lactate dehydrogenase leakage, reactive oxygen species generation, caspase 3, DNA laddering, and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling in human breast cancer cells (MDA-MB-231). Results The ultraviolet-visible absorption spectroscopy results showed a strong resonance centered on the surface of AgNPs at 420 nm. The X-ray diffraction analysis confirmed that the synthesized AgNPs were single-crystalline, corresponding with the result of transmission electron microscopy. Treatment of MDA-MB-231 breast cancer cells with various concentrations of AgNPs (1–10 μg/mL) for 24 hours revealed that AgNPs could inhibit cell viability and induce membrane leakage in a dose-dependent manner. Cells exposed to AgNPs showed increased reactive oxygen species and hydroxyl radical production. Furthermore, the apoptotic effects of AgNPs were confirmed by activation of caspase 3 and DNA nuclear fragmentation. Conclusion The results indicate that AgNPs possess cytotoxic effects with apoptotic features and suggest that the reactive oxygen species generated by

  7. The cercarial glycocalyx of Schistosoma mansoni

    PubMed Central

    1985-01-01

    Cercariae, the freshwater stage of Schistosoma mansoni infectious to man, are covered by a single unit membrane and an immunogenic glycocalyx. When cercariae penetrate the host skin, they transform to schistosomula by shedding tails, secreting mucous and enzymes, and forming microvilli over their surface. Here the loss of the glycocalyx from cercariae transforming in vitro was studied morphologically and biochemically. By scanning electron microscopy, the glycocalyx was a dense mesh composed of 15-30 nm fibrils that obscured spines on the cercarial surface. The glycocalyx was absent on organisms fixed without osmium and was partially lost when parasites aggregated in their own secretions before fixation. By transmission electron microscopy, a 1-2 microns thick mesh of 8-15-nm fibrils was seen on parasites incubated with anti-schistosomal antibodies or fixed in aldehydes containing tannic acid or ruthenium red. Cercariae transformed to schistosomula when tails were removed mechanically and parasites were incubated in saline. Within 5 min of transformation, organisms synchronously formed microvilli which elongated to 3-5 microns by 20 min and then were shed. However, considerable fibrillar material remained adherent to the double unit membrane surface of schistosomula. For biochemical labeling, parasites were treated with eserine sulfate, which blocked cercarial swimming, secretion, infectivity, and transformation to schistosomula. Material labeled by periodate oxidation and NaB3H4 was on the surface as shown by autoradiography and had an apparent molecular weight of greater than 10(6) by chromatography. Periodate- NaB3H4 glycocalyx had an isoelectric point of 5.0 +/- 0.4 and was precipitable with anti-schistosomal antibodies. More than 60% of the radiolabeled glycocalyx was released into the medium by transforming parasites in 3 h and was recovered as high molecular weight material. Parasites labeled with periodate and fluorescein-thiosemicarbazide and then

  8. Allelopathy of the invasive plant Bidens frondosa on the seed germination of Geum japonicum var. chinense.

    PubMed

    Wang, X F; Hassani, D; Cheng, Z W; Wang, C Y; Wu, J

    2014-12-12

    Five gradient concentrations (0.02, 0.04, 0.06, 0.08, and 0.10 g/mL) of leaching liquors from the roots, stems, and leaves of the invasive plant Bidens frondosa were used as conditioning fluid to examine its influence on seed germination conditions of the native plant Geum japonicum var. chinense in Huangshan. All leaching liquors of organs suppressed the seed germination of Geum japonicum var. chinense and reduced the final germination percentage and rate, and increased the germination inhibition rate, with a bimodal dependence on concentration. The leaching liquor inhibited the seed germination significantly at the concentration of 0.02 g/mL respectively. The seed germination was also inhibited as the concentration reached to 0.04 g/mL and beyond. Hence the allelopathic effects of the organs were significantly enhanced respectively. This phenomenon represented the presence of allelopathy substances in the root, stem and leaf of Bidens frondosa.

  9. Rhizobitoxine inhibition of hydrogenase synthesis in free-living Bradyrhizobium japonicum.

    PubMed Central

    Minamisawa, K; Fukai, K; Asami, T

    1990-01-01

    Rhizobitoxine produced by Bradyrhizobium species strongly prevented derepression of hydrogenase expression in free-living Bradyrhizobium japonicum, although the toxin had no effect on the activity of cells which had already synthesized hydrogenase protein. Dihydrorhizobitoxine, a structural analog of rhizobitoxine, proved to be a less potent inhibitor of hydrogenase derepression. Rhizobitoxine did not cause cell death at a concentration sufficient to eliminate hydrogenase expression. The large subunit of hydrogenase was not detectable with antibody after derepression in the presence of rhizobitoxine. The general pattern of proteins synthesized from 14C-labeled amino acids during derepression was not significantly different in the presence or absence of rhizobitoxine. These results indicated that rhizobitoxine inhibited hydrogenase synthesis in free-living B. japonicum. Cystathionine and methionine strongly prevented the inhibition of hydrogenase derepression by rhizobitoxine, suggesting that the inhibition involves the level of sulfur-containing amino acids in the cell. Images PMID:2198262

  10. A Marker-Dense Physical Map of the Bradyrhizobium japonicum Genome

    PubMed Central

    Tomkins, Jeffrey P.; Wood, Todd C.; Stacey, Minviluz G.; Loh, John T.; Judd, Adam; Goicoechea, Jose L.; Stacey, Gary; Sadowsky, Michael J.; Wing, Rod A.

    2001-01-01

    Bacterial artificial chromosome (BAC) clones are effective mapping and sequencing reagents for use with a wide variety of small and large genomes. This report describes the development of a physical framework for the genome of Bradyrhizobium japonicum, the nitrogen-fixing symbiont of soybean. A BAC library for B. japonicum was constructed that provides a 77-fold genome coverage based on an estimated genome size of 8.7 Mb. The library contains 4608 clones with an average insert size of 146 kb. To generate a physical map, the entire library was fingerprinted with HindIII, and the fingerprinted clones were assembled into contigs using the Fingerprint Contig software (FPC; Sanger Centre, UK). The FPC analysis placed 3410 clones in six large contigs. The ends of 1152 BAC inserts were sequenced to generate a sequence-tagged connector (STC) framework. To join and orient the contigs, high-density BAC colony filters were probed with 41 known gene probes and 17 end sequences from contig boundaries. STC sequences were searched against the public databases using FASTA and BLASTX algorithms. Query results allowed the identification of 113 high probability matches with putative functional identities that were placed on the physical map. Combined with the hybridization data, a high-resolution physical map with 194 positioned markers represented in two large contigs was developed, providing a marker every 45 kb. Of these markers, 177 are known or putative B. japonicum genes. Additionally, 1338 significant BLASTX results (E < 10−4) were manually sorted by function to produce a functionally categorized database of relevant B. japonicum STC sequences that can also be traced to specific locations in the physical map. PMID:11483585

  11. Symbiotic Expression of Cosmid-Borne Bradyrhizobium japonicum Hydrogenase Genes †

    PubMed Central

    Lambert, Grant R.; Harker, Alan R.; Cantrell, Michael A.; Hanus, F. Joe; Russell, Sterling A.; Haugland, Richard A.; Evans, Harold J.

    1987-01-01

    The expression of cosmid-borne Bradyrhizobium japonicum hydrogenase genes in alfalfa, clover, and soybean nodules harboring Rhizobium transconjugants was studied. Cosmid pHU52 conferred hydrogen uptake (Hup) activity in both free-living bacteria and in nodules on the different plant hosts, although in nodules the instability of the cosmid resulted in low levels of Hup activity. In contrast, cosmid pHU1, which does not confer Hup activity on free-living bacteria, gave a Hup+ phenotype in nodules on alfalfa and soybean. Nodules formed by B. japonicum USDA 123Spc(pHU1) recycled about 90% of nitrogenase-mediated hydrogen evolution. Both subunits of hydrogenase (30- and 60-kilodalton polypeptides) were detected in enzyme-linked immunosorbent assays of bacteroid preparations from nodules harboring B. japonicum strains with pHU1 or pHU52. Neither pHU53 nor pLAFR1 conferred detectable Hup activity in either nodules or free-living bacteria. Based on the physical maps of pHU1 and pHU52, it is suggested that a 5.5-kilobase EcoRI fragment unique to pHU52 contains a gene or part of a gene required for Hup activity in free-living bacteria but not in nodules. This conclusion is supported by the observation that two Tn5 insertions in the chromosome of B. japonicum USDA 122DES obtained by marker exchange with Tn5-mutagenized pHU1 abolished Hup activity in free-living bacteria but not in nodules. Images PMID:16347291

  12. Fine-tuning of nif and fix gene expression by upstream activator sequences in Bradyrhizobium japonicum.

    PubMed

    Gubler, M

    1989-02-01

    The significance of Bradyrhizobium japonicum upstream activator sequences (UASs) for differential NifA-mediated fix and nif gene expression was investigated by two means: (i) hybrid fixA- and fixB-lacZ fusions were constructed by transposing a nifH-UAS cartridge in front of their promoters; and (ii) B. japonicum mutants were generated carrying specific chromosomal deletions or UAS cartridge insertions within the fixA, fixB or nifH promoter-upstream regions. Expression of fixA was not affected, and expression of fixB decreased only to 42%, when the respective fixA and fixB promoter-upstream DNAs were deleted. This shows that in B. japonicum the NifA-dependent activation of at least the fixA promoter does not require the presence of a closely adjacent UAS. Deletion of the UASs in front of the nifH gene not only reduced the expression of nifH down to 2.5% but, surprisingly, also resulted in a reduction of the fixB mRNA level to less than 20%. This suggests that the nifH-UASs may exert a long-range effect on the expression of the 3-kb-distant fixBCX operon in nif cluster I or B. japonicum. Artificial transposition of the nifH-UASs in front of the fixA and fixB promoters strongly enhanced fixA and fixB expression.

  13. Disparate Pathways for the Biogenesis of Cytochrome Oxidases in Bradyrhizobium japonicum*

    PubMed Central

    Bühler, Doris; Rossmann, Reinhild; Landolt, Sarah; Balsiger, Sylvia; Fischer, Hans-Martin; Hennecke, Hauke

    2010-01-01

    This work addresses the biogenesis of heme-copper terminal oxidases in Bradyrhizobium japonicum, the nitrogen-fixing root nodule symbiont of soybean. B. japonicum has four quinol oxidases and four cytochrome oxidases. The latter include the aa3- and cbb3-type oxidases. Although both have a CuB center in subunit I, the subunit II proteins differ in having either a CuA center (in aa3) or a covalently bound heme c (in cbb3). Two biogenesis factors were genetically studied here, the periplasmically exposed CoxG and ScoI proteins, which are the respective homologs of the mitochondrial copper-trafficking chaperones Cox11 and Sco1 for the formation of the CuB center in subunit I and the CuA center in subunit II of cytochrome aa3. We could demonstrate copper binding to ScoI in vitro, a process for which the thiols of cysteine residues 74 and 78 in the ScoI polypeptide were shown to be essential. Knock-out mutations in the B. japonicum coxG and scoI genes led to loss of cytochrome aa3 assembly and activity in the cytoplasmic membrane, whereas the cbb3-type cytochrome oxidase apparently remained unaffected. This suggests that subunit I of the cbb3-type oxidase obtains its copper cofactor via a different pathway than cytochrome aa3. In contrast to the coxG mutation, the scoI mutation caused a decreased symbiotic nitrogen fixation activity. We hypothesize that a periplasmic B. japonicum protein other than any of the identified CuA proteins depends on ScoI and is required for an effective symbiosis. PMID:20335176

  14. Disparate pathways for the biogenesis of cytochrome oxidases in Bradyrhizobium japonicum.

    PubMed

    Bühler, Doris; Rossmann, Reinhild; Landolt, Sarah; Balsiger, Sylvia; Fischer, Hans-Martin; Hennecke, Hauke

    2010-05-21

    This work addresses the biogenesis of heme-copper terminal oxidases in Bradyrhizobium japonicum, the nitrogen-fixing root nodule symbiont of soybean. B. japonicum has four quinol oxidases and four cytochrome oxidases. The latter include the aa(3)- and cbb(3)-type oxidases. Although both have a Cu(B) center in subunit I, the subunit II proteins differ in having either a Cu(A) center (in aa(3)) or a covalently bound heme c (in cbb(3)). Two biogenesis factors were genetically studied here, the periplasmically exposed CoxG and ScoI proteins, which are the respective homologs of the mitochondrial copper-trafficking chaperones Cox11 and Sco1 for the formation of the Cu(B) center in subunit I and the Cu(A) center in subunit II of cytochrome aa(3). We could demonstrate copper binding to ScoI in vitro, a process for which the thiols of cysteine residues 74 and 78 in the ScoI polypeptide were shown to be essential. Knock-out mutations in the B. japonicum coxG and scoI genes led to loss of cytochrome aa(3) assembly and activity in the cytoplasmic membrane, whereas the cbb(3)-type cytochrome oxidase apparently remained unaffected. This suggests that subunit I of the cbb(3)-type oxidase obtains its copper cofactor via a different pathway than cytochrome aa(3). In contrast to the coxG mutation, the scoI mutation caused a decreased symbiotic nitrogen fixation activity. We hypothesize that a periplasmic B. japonicum protein other than any of the identified Cu(A) proteins depends on ScoI and is required for an effective symbiosis.

  15. Protective Effects of Membrane-Anchored and Secreted DNA Vaccines Encoding Fatty Acid-Binding Protein and Glutathione S-Transferase against Schistosoma japonicum

    PubMed Central

    Tu, Yaqin; Hu, Yang; Fan, Guorun; Chen, Zhihao; Liu, Lin; Man, Dandan; Liu, Shuojie; Tang, Chengwu; Zhang, Yin; Dai, Wuxing

    2014-01-01

    In order to explore the high performance bivalent DNA-based vaccine against schistosomes, SjFABP and Sj26GST were selected and used to construct a vaccine. Two strategies were used to construct the bivalent DNA vaccine. In the first strategy, a plasmid encoding antigen in the secreted form was used, while in the other, a plasmid encoding a truncated form of SjFABP and Sj26GST targeted to the cell surface was used. Various parameters, including antibody and cytokine response, proliferation, histopathological examination, and characterization of T cell subsets were used to evaluate the type of immune response and the level of protection against challenge infection. Injection with secreted pIRES-sjFABP-sj26GST significantly increased the levels of antibody, splenocyte proliferation, and production of IFN-γ, compared with membrane-anchored groups. Analysis of splenic T cell subsets showed that the secreted vaccine significantly increased the percentage of CD3+CD4+ and CD3+CD8+ T cells. Liver immunopathology (size of liver granulomas) was significantly reduced in the secreted group compared with the membrane-anchored groups. Moreover, challenge experiments showed that the worm and egg burdens were significantly reduced in animals immunized with recombinant vaccines. Most importantly, secreted Sj26GST-SjFABP markedly enhanced protection, by reducing worm and egg burdens by 31.8% and 24.78%, respectively, while the membrane-anchored group decreased worm and egg burdens by 24.80% and 18.80%, respectively. Taken together, these findings suggest that the secretory vaccine is more promising than the membrane-anchored vaccine, and provides support for the development and application of this vaccine. PMID:24466157

  16. Molybdate-dependent expression of the periplasmic nitrate reductase in Bradyrhizobium japonicum.

    PubMed

    Bonnard, N; Tresierra-Ayala, A; Bedmar, E J; Delgado, M J

    2005-02-01

    The napEDABC genes of Bradyrhizobium japonicum encode the periplasmic nitrate reductase, an Mo-containing enzyme which catalyses the reduction of nitrate to nitrite when oxygen concentrations are limiting. In this bacterium, another set of genes, modABC, code for a high affinity ABC-type Mo transport system. A B. japonicum modA mutant has been obtained that is not capable of growing anaerobically with nitrate and lacks nitrate reductase activity. Under nitrate respiring conditions, when Mo concentrations are limiting, the B. japonicum modA mutant lacked both the 90 kDa protein corresponding to the NapA component of the periplasmic nitrate reductase, and the membrane-bound 25 kDa c-type cytochrome NapC. Regulatory studies using a napE-lacZ fusion indicated that napE expression was highly reduced in the modA mutant background when the cells were incubated anaerobically with nitrate under Mo-deficient conditions.

  17. Unexpected urinary Schistosoma infection in a Belgian travel group returning from Malawi.

    PubMed

    Oyaert, M; Lagrange, W; Smet, G; De Feyter, K; Laffut, W

    2013-01-01

    Urinary schistosomiasis, caused by Schistosoma haematobium, is a prevalent parasitic infection in certain areas of Africa and the Middle East. Humans can be infected by cercariae when they are in contact with contaminated freshwater. The adult worms reside in the veins of the vesical and pelvis plexuses. The urinary bladder, the seminal vesicles and the lower ends of the ureters are the most commonly affected organs. In this case report, we describe an unrecognised case of urinary schistosomiasis in a woman who was part of a Belgian travel group; two other patients out of eight were also infected. In Belgium, the number of reported cases of S. haematobium infection is limited. The aim of this report is to emphasize this parasitic infection should be suspected in patients who travel to endemic areas.

  18. Glomerular lesions in experimental infections of Schistosoma mansoni in Cebus apella monkeys.

    PubMed

    De Brito, T; Gunji, J; Camargo, M E; Ceravolo, A; Da Silva, L C

    1971-01-01

    Three monkeys (Cebus apella) experimentally infected with Schistosoma mansoni studied for periods of 19, 14, and 11 months showed deposits containing gamma-globulin in subendothelial and subepithelial basal membranes and in basement membranes proper. The glomeruli showed mild reactivity characterized by local hypertrophy and hyperplasia of mesangial cells. Such findings were close to those observed by us in the kidney of hepatosplenic schistosomiasis patients without evidence of renal disease. The distribution of the deposits, both in human and experimental disease, are suggestive of preformed, non-glomerular antigen-antibody complexes that form in a zone of excess antigen and become trapped in the glomerular capillaries.The possibility exists, but has not yet been proved beyond doubt, that renal disease in schistosomiasis patients could be the end result of this pathogenetic mechanism.

  19. Murine immunization by cesium-137 irradiation attenuated Schistosoma mansoni cercariae

    SciTech Connect

    Stek, M. Jr.; Minard, P.; Cruess, D.F.

    1984-06-01

    Cesium-137, becoming a more readily available ionizing gamma radiation source for laboratory use, was shown to effectively attenuate Schistosoma mansoni cercariae for vaccine production. In parallel comparison studies with the murine model, cesium-137 attenuated cercariae consistently afforded better protection than did the cobalt-60 prepared vaccine. Dose-response data indicated that the optimal total irradiation with cesium-137 was between 45 and 50 Krad.

  20. Soybean Metabolites Regulated in Root Hairs in Response to the Symbiotic Bacterium Bradyrhizobium japonicum1[W][OA

    PubMed Central

    Brechenmacher, Laurent; Lei, Zhentian; Libault, Marc; Findley, Seth; Sugawara, Masayuki; Sadowsky, Michael J.; Sumner, Lloyd W.; Stacey, Gary

    2010-01-01

    Nodulation of soybean (Glycine max) root hairs by the nitrogen-fixing symbiotic bacterium Bradyrhizobium japonicum is a complex process coordinated by the mutual exchange of diffusible signal molecules. A metabolomic study was performed to identify small molecules produced in roots and root hairs during the rhizobial infection process. Metabolites extracted from roots and root hairs mock inoculated or inoculated with B. japonicum were analyzed by gas chromatography-mass spectrometry and ultraperformance liquid chromatography-quadrupole time of flight-mass spectrometry. These combined approaches identified 2,610 metabolites in root hairs. Of these, 166 were significantly regulated in response to B. japonicum inoculation, including various (iso)flavonoids, amino acids, fatty acids, carboxylic acids, and various carbohydrates. Trehalose was among the most strongly induced metabolites produced following inoculation. Subsequent metabolomic analyses of root hairs inoculated with a B. japonicum mutant defective in the trehalose synthase, trehalose 6-phosphate synthase, and maltooligosyltrehalose synthase genes showed that the trehalose detected in the inoculated root hairs was primarily of bacterial origin. Since trehalose is generally considered an osmoprotectant, these data suggest that B. japonicum likely experiences osmotic stress during the infection process, either on the root hair surface or within the infection thread. PMID:20534735

  1. Functional characterization of the Bradyrhizobium japonicum modA and modB genes involved in molybdenum transport.

    PubMed

    Delgado, María J; Tresierra-Ayala, Alvaro; Talbi, Chouhra; Bedmar, Eulogio J

    2006-01-01

    A modABC gene cluster that encodes an ABC-type, high-affinity molybdate transporter from Bradyrhizobium japonicum has been isolated and characterized. B. japonicum modA and modB mutant strains were unable to grow aerobically or anaerobically with nitrate as nitrogen source or as respiratory substrate, respectively, and lacked nitrate reductase activity. The nitrogen-fixing ability of the mod mutants in symbiotic association with soybean plants grown in a Mo-deficient mineral solution was severely impaired. Addition of molybdate to the bacterial growth medium or to the plant mineral solution fully restored the wild-type phenotype. Because the amount of molybdate required for suppression of the mutant phenotype either under free-living or under symbiotic conditions was dependent on sulphate concentration, it is likely that a sulphate transporter is also involved in Mo uptake in B. japonicum. The promoter region of the modABC genes has been characterized by primer extension. Reverse transcription and expression of a transcriptional fusion, P(modA)-lacZ, was detected only in a B. japonicum modA mutant grown in a medium without molybdate supplementation. These findings indicate that transcription of the B. japonicum modABC genes is repressed by molybdate.

  2. Overproduction of Ristomycin A by Activation of a Silent Gene Cluster in Amycolatopsis japonicum MG417-CF17

    PubMed Central

    Spohn, Marius; Kirchner, Norbert; Kulik, Andreas; Jochim, Angelika; Wolf, Felix; Muenzer, Patrick; Borst, Oliver; Gross, Harald; Wohlleben, Wolfgang

    2014-01-01

    The emergence of antibiotic-resistant pathogenic bacteria within the last decades is one reason for the urgent need for new antibacterial agents. A strategy to discover new anti-infective compounds is the evaluation of the genetic capacity of secondary metabolite producers and the activation of cryptic gene clusters (genome mining). One genus known for its potential to synthesize medically important products is Amycolatopsis. However, Amycolatopsis japonicum does not produce an antibiotic under standard laboratory conditions. In contrast to most Amycolatopsis strains, A. japonicum is genetically tractable with different methods. In order to activate a possible silent glycopeptide cluster, we introduced a gene encoding the transcriptional activator of balhimycin biosynthesis, the bbr gene from Amycolatopsis balhimycina (bbrAba), into A. japonicum. This resulted in the production of an antibiotically active compound. Following whole-genome sequencing of A. japonicum, 29 cryptic gene clusters were identified by genome mining. One of these gene clusters is a putative glycopeptide biosynthesis gene cluster. Using bioinformatic tools, ristomycin (syn. ristocetin), a type III glycopeptide, which has antibacterial activity and which is used for the diagnosis of von Willebrand disease and Bernard-Soulier syndrome, was deduced as a possible product of the gene cluster. Chemical analyses by high-performance liquid chromatography and mass spectrometry (HPLC-MS), tandem mass spectrometry (MS/MS), and nuclear magnetic resonance (NMR) spectroscopy confirmed the in silico prediction that the recombinant A. japonicum/pRM4-bbrAba synthesizes ristomycin A. PMID:25114137

  3. Use of repetitive sequences and the polymerase chain reaction technique to classify genetically related Bradyrhizobium japonicum serocluster 123 strains

    SciTech Connect

    Judd, A.K.; Sadowsky, M.J. MSU-DOE Plant Research Lab., East Lansing, MI ); Schneider, M.; Bruijn, F.J. de Michigan State Univ., East Lansing )

    1993-06-01

    Bacteria of the genus Bradyrhizobium are slow-growing, gram-negative, heterotrophic and have the ability to form root nodules on several leguminous plants. In the upper midwest USA, members of B. japonicum serocluster 123 are the dominant indigenous competitors for the nodulation of soybeans. However, the current serological divisions fail to adequately reflect the genetic and phenotypic diversity among member isolates. This article describes the use of REP and ERIC PCR fingerprinting and RFLP analysis using a hyperreiterated DNA probe to classiby serologically related and genetically similar B. japonicum serocluster 123 strains. In addition the comparison of 15 serologically distinct B. japonicum and Bradyrhizobia spp. strains by using REP and ERIC PCR fingerprint analysis is presented. 25 refs., 8 figs., 1 tab.

  4. Structural and kinetic analysis of Schistosoma mansoni Adenylosuccinate Lyase (SmADSL).

    PubMed

    Romanello, Larissa; Serrão, Vitor Hugo Balasco; de Souza, Juliana Roberta Torini; Bird, Louise E; Nettleship, Joanne E; Rada, Heather; Reddivari, Yamini; Owens, Ray J; de Marco, Ricardo; Brandão-Neto, José; Pereira, Humberto D'Muniz

    2017-03-24

    Schistosoma mansoni is the parasite responsible for schistosomiasis, a disease that affects about 218 million people worldwide. Currently, both direct treatment and disease control initiatives rely on chemotherapy using a single drug, praziquantel. Concerns over the possibility of resistance developing to praziquantel, have stimulated efforts to develop new drugs for the treatment of schistosomiasis. Schistosomes do not have the de novo purine biosynthetic pathway, and instead depend entirely on the purine salvage pathway to supply its need for purines. The purine salvage pathway has been reported as a potential target for developing new drugs against schistosomiasis. Adenylosuccinate lyase (SmADSL) is an enzyme in this pathway, which cleaves adenylosuccinate (ADS) into adenosine 5'-monophosphate (AMP) and fumarate. SmADSL kinetic characterization was performed by isothermal titration calorimetry (ITC) using both ADS and SAICAR as substrates. Structures of SmADSL in Apo form and in complex with AMP were elucidated by x-ray crystallography revealing a highly conserved tetrameric structure required for their function since the active sites is formed from residues of three different subunits. The active sites are also highly conserved between species and it is difficult to identify a potent species-specific inhibitor for the development of new therapeutic agents. In contrast, several mutagenesis studies have demonstrated the importance of dimeric interface residues in the stability of the quaternary structure of the enzyme. The lower conservation of these residues between SmADSL and human ADSL could be used to lead the development of anti-schistosomiasis drugs based on disruption of subunit interfaces. These structures and kinetics data add another layer of information to Schistosoma mansoni purine salvage pathway.

  5. Decline in infection-related morbidities following drug-mediated reductions in the intensity of Schistosoma infection: A systematic review and meta-analysis

    PubMed Central

    Andrade, Gisele; Bertsch, David J.; Gazzinelli, Andrea

    2017-01-01

    Background 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. Methodology/Principal findings 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. Conclusion/Significance While there are challenges to implementing therapy for schistosomiasis, and praziquantel therapy is not fully

  6. The role of Bradyrhizobium japonicum nitric oxide reductase in nitric oxide detoxification in soya bean root nodules.

    PubMed

    Meakin, G E; Jepson, B J N; Richardson, D J; Bedmar, E J; Delgado, M J

    2006-02-01

    The identification of nitric oxide-bound leghaemoglobin within soya bean nodules has led to the question of how Bradyrhizobium japonicum bacteroids overcome the toxicity of this nitric oxide. It has previously been shown that one candidate for nitric oxide detoxification, the respiratory nitric oxide reductase, is expressed in soya bean nodules from plants supplied with nitrate. In this paper, the role of this enzyme in nitric oxide detoxification is assessed and discussion is provided on other possible B. japonicum nitric oxide detoxification systems.

  7. Efficiency of different formulations of Bradyrhizobium japonicum and effect of co-inoculation of Bacillus subtilis with two different strains of Bradyrhizobium japonicum.

    PubMed

    Atieno, Mary; Herrmann, Laetitia; Okalebo, Robert; Lesueur, Didier

    2012-07-01

    A key constraint in successfully obtaining an effective inoculant is overcoming difficulties in formulating a viable and user-friendly final product and maintaining the microbial cells in a competent state. Co-cultures of rhizobia and PGPR (Plant Growth Promoting Rhizobacteria) are a logical next subject for formulation researchers as they can influence the efficacy of rhizobia. A greenhouse experiment was set to assess the formulation effect of one strain i.e. Bradyrhizobium japonicum, 532c (granules, liquid and broth) and also to determine the efficiency of co-inoculation of Bacillus with two commercial strains of B. japonicum (532c and RCR 3407) on 2 soybean (Glycine max L.) varieties. PCR-RFLP analysis was used to determine the nodule occupancy in each treatment. Most of the inoculants showed increased nodulation and biomass yields (by approximately 2-5 and 4-10 g plant(-1) respectively) as compared to the uninoculated controls. TGx1740-2F showed no significant differences in nodule fresh weights for the formulation effect while the co-inoculants increased the nodule fresh weights by up to 4 g plant(-1). The liquid and granule-based inoculants induced higher biomass yields (4-8 g plant(-1)) suggesting a possible impact of formulation on the effectiveness of the inoculants. The co-inoculants also gave higher yields but showing no significant differences to the rhizobial inoculants. Nodule occupancy was 100 % for the rhizobial inoculants as well as the co-inoculants emphasizing the infectivity and high competitiveness of 532c and RCR 3407 strains despite the high population of indigenous rhizobia.

  8. Expression of nir, nor and nos denitrification genes from Bradyrhizobium japonicum in soybean root nodules.

    PubMed

    Mesa, Socorno; Alché Jd, Juan de Dios; Bedmar, Eulogio; Delgado, Maria J.

    2004-02-01

    Expression of Bradyrhizobium japonicum wild-type strain USDA110 nirK, norC and nosZ denitrification genes in soybean root nodules was studied by in situ histochemical detection of beta-galactosidase activity. Similarly, P(nirK)-lacZ, P(norC)-lacZ, and P(nosZ)-lacZ fusions were also expressed in bacteroids isolated from root nodules. Levels of beta-galactosidase activity were similar in both bacteroids and nodule sections from plants that were solely N(2)-dependent or grown in the presence of 4 mM KNO(3). These findings suggest that oxygen, and not nitrate, is the main factor controlling expression of denitrification genes in soybean nodules. In plants not amended with nitrate, B. japonicum mutant strains GRK308, GRC131, and GRZ25, that were altered in the structural nirK, norC and nosZ genes, respectively, showed a wild-type phenotype with regard to nodule number and nodule dry weight as well as plant dry weight and nitrogen content. In the presence of 4 mM KNO(3), plants inoculated with either GRK308 or GRC131 showed less nodules, and lower plant dry weight and nitrogen content, relative to those of strains USDA110 and GRZ25. Taken together, the present results revealed that although not essential for nitrogen fixation, mutation of either the structural nirK or norC genes encoding respiratory nitrite reductase and nitric oxide reductase, respectively, confers B. japonicum reduced ability for nodulation in soybean plants grown with nitrate. Furthermore, because nodules formed by each the parental and mutant strains exhibited nitrogenase activity, it is possible that denitrification enzymes play a role in nodule formation rather than in nodule function.

  9. Factors Influencing the Synthesis of Polysaccharide by Bradyrhizobium japonicum Bacteroids in Field-Grown Soybean Nodules

    PubMed Central

    Streeter, John G.; Salminen, Seppo O.; Beuerlein, James E.; Schmidt, Walter H.

    1994-01-01

    Certain strains of Bradyrhizobium japonicum produce large quantities of polysaccharide in soybean (Glycine max (L.) Merr.) nodules, and nodule polysaccharide (NPS) is different from that produced in culture. A previous survey of field-grown plants showed highly variable levels of NPS among field sites. To obtain clues about the possible function of NPS, we conducted two additional surveys of field-grown plants. The amount of polysaccharide in bulk samples of nodules was not associated with soil type, texture, slope, drainage, or any of the measured soil chemical properties except pH and [Ca]. Correlations with pH and [Ca] were positive and highly significant for two independent surveys involving a total of 77 sites in two years. In a preliminary comparison of high and low levels of Ca supplied to soybean plants grown in silica sand in a greenhouse, a high level of Ca (200 mg of Ca liter-1) increased the NPS level and increased the Ca content of the polysaccharide fraction. B. japonicum isolates from 450 nodules collected at 10 field sites in 1993 were used to form nodules on soybean plants grown in sand culture in a greenhouse in order to examine bacterial phenotype under controlled conditions. Results showed that the NPS level in the bulk nodule sample from any given site was a function of the proportion of nodule occupants that were capable of NPS synthesis. Thus, a higher soil pH and/or [Ca] may positively influence the survival of B. japonicum capable of synthesis of the nodule-specific polysaccharide. PMID:16349358

  10. Transcription Activation In Vitro by the Bradyrhizobium japonicum Regulatory Protein FixK2

    PubMed Central

    Mesa, Socorro; Ucurum, Zöhre; Hennecke, Hauke; Fischer, Hans-Martin

    2005-01-01

    In Bradyrhizobium japonicum, the N2-fixing root nodule endosymbiont of soybean, a group of genes required for microaerobic, anaerobic, or symbiotic growth is controlled by FixK2, a key regulator that is part of the FixLJ-FixK2 cascade. FixK2 belongs to the family of cyclic AMP receptor protein/fumarate and nitrate reductase (CRP/FNR) transcription factors that recognize a palindromic DNA motif (CRP/FNR box) associated with the regulated promoters. Here, we report on a biochemical analysis of FixK2 and its transcription activation activity in vitro. FixK2 was expressed in Escherichia coli and purified as a soluble N-terminally histidine-tagged protein. Gel filtration experiments revealed that increasing the protein concentration shifts the monomer-dimer equilibrium toward the dimer. Purified FixK2 productively interacted with the B. japonicum σ80-RNA polymerase holoenzyme, but not with E. coli σ70-RNA polymerase holoenzyme, to activate transcription from the B. japonicum fixNOQP, fixGHIS, and hemN2 promoters in vitro. Furthermore, FixK2 activated transcription from the E. coli FF(−41.5) model promoter, again only in concert with B. japonicum RNA polymerase. All of these promoters are so-called class II CRP/FNR-type promoters. We showed by specific mutagenesis that the FixK2 box at nucleotide position −40.5 in the hemN2 promoter, but not that at −78.5, is crucial for activation both in vivo and in vitro, which argues against recognition of a potential class III promoter. Given the lack of any evidence for the presence of a cofactor in purified FixK2, we surmise that FixK2 alone is sufficient to activate in vitro transcription to at least a basal level. This contrasts with all well-studied CRP/FNR-type proteins, which do require coregulators. PMID:15866917

  11. Serodiagnosis of Schistosoma mansoni infections in an endemic area of Burkina Faso: performance of several immunological tests with different parasite antigens.

    PubMed

    Sorgho, Hermann; Bahgat, Mahmoud; Poda, Jean-Noel; Song, Wenjian; Kirsten, Christa; Doenhoff, Michael J; Zongo, Issaka; Ouédraogo, Jean-Bosco; Ruppel, Andreas

    2005-02-01

    The performance of indirect haemagglutination assays (IHA), enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescent antibody tests (IFAT) were compared with 450 sera from a Schistosoma mansoni-endemic area in Burkina Faso. All participants in this survey provided at least one sample each of stool, urine and serum. From those with an egg-negative Kato-Katz thick smear, a second stool sample was examined. IHA was based on either extracts of adult S. mansoni worms (SmIHA) or S. japonicum egg antigen (SjIHA). For ELISA, three antigen preparations were used, namely: (i) soluble S. mansoni adult worm antigens (SWAP); (ii) soluble S. mansoni egg antigens (SEA); and (iii) a cationic exchange fraction of S. mansoni eggs (CEF6). IFAT was performed with S. mansoni male worm sections. Among the egg-excretors, the sensitivity of ELISA was high and egg antigens performed slightly better (SEA, 96%; CEF6, 97%) than worm antigen (94%). Sensitivity of IHA was satisfactory with homologous (Sm, >85%), but not heterologous (Sj, 56%) parasite antigen. In IFAT, the parenchyma-associated fluorescence showed high sensitivity (95%), but gut-associated fluorescence, which is known to be a sensitive diagnostic marker for schistosome-infected European travelers, was observed only in 76% of a sub-sample of 100 of the endemic sera. Among sera from egg-negative individuals, many gave positive reactions in several or all of the tests employed. These reactions (formally "false positive") are considered to represent true infections, since chemotherapy had not yet been delivered to this population. For the purpose of further surveys in Burkina Faso or other resource-poor settings, we suggest IHA as an accurate diagnostic test and propose to further improve its performance by including egg rather than worm antigens.

  12. Epitopes rationally selected through computational analyses induce T-cell proliferation in mice and are recognized by serum from individuals infected with Schistosoma mansoni.

    PubMed

    Lopes, Marcelo D; Oliveira, Flávio M; Coelho, Ivan E V; Passos, Maria J F; Alves, Clarice C; Taranto, Alex G; Júnior, Moacyr C; Santos, Luciana L; Fonseca, Cristina T; Villar, José A F P; Lopes, Débora O

    2017-04-03

    Schistosomiasis is the second leading cause of death due to parasitic diseases in the world. Seeking an alternative for the control of disease, the World Health Organization funded the genome sequencing of the major species related to schistosomiasis to identify potential vaccines and therapeutic targets. Therefore, the aim of this work was to select T and B-cell epitopes from Schistosoma mansoni through computational analyses and evaluate the immunological potential of epitopes in vitro. Extracellular regions of membrane proteins from the Schistosoma mansoni were used to predict promiscuous epitopes with affinity to different human Major Histocompatibility Class II (MHCII) molecules by bioinformatics analysis. The three-dimensional structure of selected epitopes was constructed and used in molecular docking to verify the interaction with murine MHCII H2-IA(b) . In this process, four epitopes were selected and synthesized to assess their ability to stimulate proliferation of CD4(+) T lymphocytes in mice splenocyte cultures. The results showed that Sm041370 and Sm168240 epitopes induced significant cell proliferation. Additionally, the four epitopes were used as antigens in the Indirect Enzyme-Linked Immunosorbent Assay (ELISA) to assess the recognition by serum from individuals infected with Schistosoma mansoni. Sm140560, Sm168240 and Sm041370 epitopes were recognized by infected individuals IgG antibodies. Therefore, Sm041370 and Sm168240 epitopes that stood out in in silico and in vitro analyses could be promising antigens in schistosomiasis vaccine development or diagnostic kits. This article is protected by copyright. All rights reserved.

  13. The role of the immunological background of mice in the genetic variability of Schistosoma mansoni as detected by random amplification of polymorphic DNA.

    PubMed

    Cossa-Moiane, I L; Mendes, T; Ferreira, T M; Mauricio, I; Calado, M; Afonso, A; Belo, S

    2015-11-01

    Schistosomiasis is a parasitic disease caused by flatworms of the genus Schistosoma. Among the Schistosoma species known to infect humans, S. mansoni is the most frequent cause of intestinal schistosomiasis in sub-Saharan Africa and South America: the World Health Organization estimates that about 200,000 deaths per year result from schistosomiasis in sub-Saharan Africa alone. The Schistosoma life cycle requires two different hosts: a snail as intermediate host and a mammal as definitive host. People become infected when they come into contact with water contaminated with free-living larvae (e.g. when swimming, fishing, washing). Although S. mansoni has mechanisms for escaping the host immune system, only a minority of infecting larvae develop into adults, suggesting that strain selection occurs at the host level. To test this hypothesis, we compared the Belo Horizonte (BH) strain of S. mansoni recovered from definitive hosts with different immunological backgrounds using random amplification of polymorphic DNA-polymerase chain reaction (RAPD-PCR). Schistosoma mansoni DNA profiles of worms obtained from wild-type (CD1 and C57BL/6J) and mutant (Jα18- / - and TGFβRIIdn) mice were analysed. Four primers produced polymorphic profiles, which can therefore potentially be used as reference biomarkers. All male worms were genetically distinct from females isolated from the same host, with female worms showing more specific fragments than males. Of the four host-derived schistosome populations, female and male adults recovered from TGFβRIIdn mice showed RAPD-PCR profiles that were most similar to each other. Altogether, these data indicate that host immunological backgrounds can influence the genetic diversity of parasite populations.

  14. Schistosoma co-infection protects against brain pathology but does not prevent severe disease and death in a murine model of cerebral malaria.

    PubMed

    Bucher, Kirsten; Dietz, Klaus; Lackner, Peter; Pasche, Bastian; Fendel, Rolf; Mordmüller, Benjamin; Ben-Smith, Anne; Hoffmann, Wolfgang H

    2011-01-01

    Co-infections of helminths and malaria parasites are common in human populations in most endemic areas. It has been suggested that concomitant helminth infections inhibit the control of malaria parasitemia but down-modulate severe malarial disease. We tested this hypothesis using a murine co-infection model of schistosomiasis and cerebral malaria. C57BL/6 mice were infected with Schistosoma mansoni and 8-9 weeks later, when Schistosoma infection was patent, mice were co-infected with Plasmodium berghei ANKA strain. We found that a concomitant Schistosoma infection increased parasitemia at the beginning of the P. berghei infection. It did not protect against P. berghei-induced weight loss and hypothermia, and P. berghei-mono-infected as well as S. mansoni-P. berghei-co-infected animals showed a high case fatality between days 6 and 8 of malarial infection. However, co-infection significantly reduced P. berghei-induced brain pathology. Over 40% of the S. mansoni-P. berghei-co-infected animals that died during this period were completely protected against haemorrhaging, plugging of blood vessels and infiltration, indicating that mortality in these animals was not related to cerebral disease. Schistosoma mansoni-P. berghei-co-infected mice had elevated plasma concentrations of IL-5 and IL-13 and on day 6 lower levels of IFN-γ, IL-10, monocyte chemoattractant protein-1 (MCP-1) and monokine induced by IFN-γ (MIG) than P. berghei-mono-infected mice. We conclude that in P. berghei infections, disease and early death are caused by distinct pathogenic mechanisms, which develop in parallel and are differentially influenced by the immune response to S. mansoni. This might explain why, in co-infected mice, death could be induced in the absence of brain pathology.

  15. Analysis of cDNA encoding the hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) of Schistosoma mansoni; a putative target for chemotherapy.

    PubMed Central

    Craig, S P; McKerrow, J H; Newport, G R; Wang, C C

    1988-01-01

    Because of the lack of de novo purine biosynthesis, hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) is a critical enzyme in the purine metabolic pathway of the human parasite, Schistosoma mansoni. Using a cDNA clone encoding mouse HGPRTase and subsequently a synthetic oligonucleotide derived from sequencing a clone of genomic DNA, two clones were isolated from an adult schistosome cDNA library. One clone is 1.374 Kilobases (Kb) long and has an open reading frame of 693 bases. The deduced 231 amino acid sequence has 47.9% identity in a 217 amino acid overlap with human HGPRTase. Northern blot analysis indicates that the full length of mRNA for the S. mansoni HGPRTase is 1.45-1.6 Kb. Analysis of the primary structures of the putative active site for human and parasite enzymes reveal specific differences which may eventually be exploitable in the design of drugs for the treatment of schistosomiasis. Images PMID:3136439

  16. The species of the genus Bulinus, intermediate hosts of Schistosoma*

    PubMed Central

    Mandahl-Barth, G.

    1965-01-01

    The conditions of snail life in African inland waters favour the evolution of microgeographical races while hindering the formation of new species, and the distinctions between many of the bulinid intermediate hosts of Schistosoma are consequently blurred. In this paper the author comments on the distinguishing characters that have been established for the known Bulinus species and subspecies and summarizes the present knowledge of their distribution and importance as intermediate hosts. His work is based on the examination of over 1540 snail samples received at the WHO Snail Identification Centre in Charlottenlund, Denmark. PMID:5294263

  17. Dracunculus medinensis and Schistosoma mansoni contain opiate alkaloids.

    PubMed

    Zhu, W; Baggerman, G; Secor, W Evan; Casares, F; Pryor, S C; Fricchione, G L; Ruiz-Tiben, E; Eberhard, M L; Bimi, L; Stefano, G B

    2002-04-01

    The results of analysis, by high-performance liquid chromatography coupled with electrochemical detection and by nano-electrospray-ionization, double quadrupole/orthogonal-acceleration, time-of-flight mass spectrometry, indicate that adult Dracunculus medinensis and Schistosoma mansoni both contain the opiate alkaloid morphine and that D. medinesis also contains the active metabolite of morphine, morphine 6-glucuronide. From these and previous observations, it would appear that many helminths are probably using opiate alkaloids as potent immunosuppressive and antinociceptive signal molecules, to down-regulate immunosurveillance responsiveness and pain signalling in their hosts.

  18. Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis.

    PubMed

    Sady, Hany; Al-Mekhlafi, Hesham M; Ngui, Romano; Atroosh, Wahib M; Al-Delaimy, Ahmed K; Nasr, Nabil A; Dawaki, Salwa; Abdulsalam, Awatif M; Ithoi, Init; Lim, Yvonne A L; Chua, Kek Heng; Surin, Johari

    2015-07-16

    The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1) gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct) values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01). In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays.

  19. In Silico Repositioning-Chemogenomics Strategy Identifies New Drugs with Potential Activity against Multiple Life Stages of Schistosoma mansoni

    PubMed Central

    Neves, Bruno J.; Braga, Rodolpho C.; Bezerra, José C. B.; Cravo, Pedro V. L.; Andrade, Carolina H.

    2015-01-01

    Morbidity and mortality caused by schistosomiasis are serious public health problems in developing countries. Because praziquantel is the only drug in therapeutic use, the risk of drug resistance is a concern. In the search for new schistosomicidal drugs, we performed a target-based chemogenomics screen of a dataset of 2,114 proteins to identify drugs that are approved for clinical use in humans that may be active against multiple life stages of Schistosoma mansoni. Each of these proteins was treated as a potential drug target, and its amino acid sequence was used to interrogate three databases: Therapeutic Target Database (TTD), DrugBank and STITCH. Predicted drug-target interactions were refined using a combination of approaches, including pairwise alignment, conservation state of functional regions and chemical space analysis. To validate our strategy, several drugs previously shown to be active against Schistosoma species were correctly predicted, such as clonazepam, auranofin, nifedipine, and artesunate. We were also able to identify 115 drugs that have not yet been experimentally tested against schistosomes and that require further assessment. Some examples are aprindine, gentamicin, clotrimazole, tetrabenazine, griseofulvin, and cinnarizine. In conclusion, we have developed a systematic and focused computer-aided approach to propose approved drugs that may warrant testing and/or serve as lead compounds for the design of new drugs against schistosomes. PMID:25569258

  20. In silico repositioning-chemogenomics strategy identifies new drugs with potential activity against multiple life stages of Schistosoma mansoni.

    PubMed

    Neves, Bruno J; Braga, Rodolpho C; Bezerra, José C B; Cravo, Pedro V L; Andrade, Carolina H

    2015-01-01

    Morbidity and mortality caused by schistosomiasis are serious public health problems in developing countries. Because praziquantel is the only drug in therapeutic use, the risk of drug resistance is a concern. In the search for new schistosomicidal drugs, we performed a target-based chemogenomics screen of a dataset of 2,114 proteins to identify drugs that are approved for clinical use in humans that may be active against multiple life stages of Schistosoma mansoni. Each of these proteins was treated as a potential drug target, and its amino acid sequence was used to interrogate three databases: Therapeutic Target Database (TTD), DrugBank and STITCH. Predicted drug-target interactions were refined using a combination of approaches, including pairwise alignment, conservation state of functional regions and chemical space analysis. To validate our strategy, several drugs previously shown to be active against Schistosoma species were correctly predicted, such as clonazepam, auranofin, nifedipine, and artesunate. We were also able to identify 115 drugs that have not yet been experimentally tested against schistosomes and that require further assessment. Some examples are aprindine, gentamicin, clotrimazole, tetrabenazine, griseofulvin, and cinnarizine. In conclusion, we have developed a systematic and focused computer-aided approach to propose approved drugs that may warrant testing and/or serve as lead compounds for the design of new drugs against schistosomes.

  1. Redox balance mechanisms in Schistosoma mansoni rely on peroxiredoxins and albumin and implicate peroxiredoxins as novel drug targets.

    PubMed

    Sayed, Ahmed A; Cook, Shawna K; Williams, David L

    2006-06-23

    Schistosoma mansoni, a causative agent of schistosomiasis, resides in the hepatic portal circulation of their human host up to 30 years without being eliminated by the host immune attack. Production of an antioxidant "firewall," which would neutralize the oxidative assault generated by host immune defenses, is one proposed survival mechanism of the parasite. Schistosomes lack catalase, the main H2O2-neutralizing enzyme of many organisms, and their glutathione peroxidases are in the phospholipid class with poor reactivity toward H2O2. Evidence implicates peroxiredoxins (Prx) as providing the main enzymatic activity to reduce H2O2 in the parasite. Quantitative monitoring of Prx mRNAs during parasite life cycle indicated that Prx proteins are differentially expressed, with highest expression occurring in adult stages (oxidative resistant stages). Incubation of schistosomula with Prx1 double-stranded RNA knocked down total Prx enzymatic activity and resulted in lowered survival of cultured parasites compared with controls demonstrating that Prx are essential parasite proteins. These results represent the first report of lethal gene silencing in Schistosoma. Investigation of downstream effects of Prx silencing revealed an abrupt increase of lipid peroxides and the generation of several oxidized proteins. Using mass spectrometry, parasite albumin and actin were identified as the main oxidized proteins. Gene expression analysis showed that schistosome albumin was induced by oxidative stress. This study highlights Prx proteins as essential parasite proteins and potential new targets for anti-schistosome drug development and albumin as a novel, sacrificial oxidant scavenging protein in parasite redox regulation.

  2. A Selective Medium for the Isolation and Quantification of Bradyrhizobium japonicum and Bradyrhizobium elkanii Strains from Soils and Inoculants.

    PubMed

    Tong, Z; Sadowsky, M J

    1994-02-01

    The ecological examination of members of the family Rhizobiaceae has been hampered by the lack of a selective medium for isolation of root nodule bacteria from soil. A novel non-antibiotic-containing medium has been developed which allows selective isolation of Bradyrhizobium japonicum and B. elkanii strains from soil and inoculants. The medium, BJSM, is based on the resistance of B.japonicum and B. elkanii strains to more than 40 mug of the metals ions Zn and Co per ml. BJSM does not allow growth of Rhizobium sp. strains. We used BJSM to isolate bacteria from a Hubbard soil and from several commercially prepared soybean inoculants. Ninety-eight percent of the isolates obtained from Hubbard soil nodulated Glycine max cv. Kasota, and between 55 and 95% of the isolates from the commercial inoculants had the ability to nodulate soybeans. Numbers of bradyrhizobia obtained by using BJSM, strain-specific fluorescent antibodies, and the most-probable-number plant infection assay indicated that the three techniques were comparable in quantifying B. japonicum strains in soils and inoculants, although most-probable-number counts were generally 0.5 order of magnitude greater than those obtained by using BJSM. Results of our studies indicate that BJSM is useful for direct isolation and quantification of B. japonicum and B. elkanii from natural soils and inoculants. This medium may prove to be an important tool for autecological and enumeration studies of diverse populations of bradyrhizobia and as a quality control method for soybean inoculants.

  3. Genome Sequence of Bradyrhizobium japonicum E109, One of the Most Agronomically Used Nitrogen-Fixing Rhizobacteria in Argentina

    PubMed Central

    Torres, Daniela; Revale, Santiago; Obando, Melissa; Maroniche, Guillermo; Paris, Gastón; Perticari, Alejandro; Vazquez, Martín; Wisniewski-Dyé, Florence; Martínez-Abarca, Francisco

    2015-01-01

    We present here the complete genome sequence of Bradyrhizobium japonicum strain E109, one of the most used rhizobacteria for soybean inoculation in Argentina since the 1970s. The genome consists of a 9.22-Mbp single chromosome and contains several genes related to nitrogen fixation, phytohormone biosynthesis, and a rhizospheric lifestyle. PMID:25700406

  4. Nucleotide sequence of the genetic loci encoding subunits of Bradyrhizobium japonicum uptake hydrogenase.

    PubMed Central

    Sayavedra-Soto, L A; Powell, G K; Evans, H J; Morris, R O

    1988-01-01

    An indispensable part of the hydrogen-recycling system in Bradyrhizobium japonicum is the uptake hydrogenase, which is composed of 34.5- and 65.9-kDa subunits. The gene encoding the large subunit is located on a 5.9-kilobase fragment of the H2-uptake-complementing cosmid pHU52 [Zuber, M., Harker, A.R., Sultana, M.A. & Evans, H.J. (1986) Proc. Natl. Acad. Sci. USA 83, 7668-7672]. We have now determined that the structural genes for both subunits are present on this fragment. Two open reading frames are present that correspond in size and deduced amino acid sequence to the hydrogenase subunits, except that the small-subunit coding region contains a leader peptide of 46 amino acids. The two genes are separated by a 32-nucleotide intergenic region and likely constitute an operon. Comparison of the deduced amino acid sequences of the B. japonicum genes with those from Desulfovibrio gigas, Desulfovibrio baculatus, and Rhodobacter capsulatus indicates significant sequence identity. Images PMID:3054886

  5. Mitigation of nitrous oxide emissions from soils by Bradyrhizobium japonicum inoculation

    NASA Astrophysics Data System (ADS)

    Itakura, Manabu; Uchida, Yoshitaka; Akiyama, Hiroko; Hoshino, Yuko Takada; Shimomura, Yumi; Morimoto, Sho; Tago, Kanako; Wang, Yong; Hayakawa, Chihiro; Uetake, Yusuke; Sánchez, Cristina; Eda, Shima; Hayatsu, Masahito; Minamisawa, Kiwamu

    2013-03-01

    Nitrous oxide (N2O) is a greenhouse gas that is also capable of destroying the ozone layer. Agricultural soil is the largest source of N2O (ref. ). Soybean is a globally important leguminous crop, and hosts symbiotic nitrogen-fixing soil bacteria (rhizobia) that can also produce N2O (ref. ). In agricultural soil, N2O is emitted from fertilizer and soil nitrogen. In soybean ecosystems, N2O is also emitted from the degradation of the root nodules. Organic nitrogen inside the nodules is mineralized to NH4+, followed by nitrification and denitrification that produce N2O. N2O is then emitted into the atmosphere or is further reduced to N2 by N2O reductase (N2OR), which is encoded by the nosZ gene. Pure culture and vermiculite pot experiments showed lower N2O emission by nosZ+ strains and nosZ++ strains (mutants with increased N2OR activity) of Bradyrhizobium japonicum than by nosZ- strains. A pot experiment using soil confirmed these results. Although enhancing N2OR activity has been suggested as a N2O mitigation option, this has never been tested in the field. Here, we show that post-harvest N2O emission from soybean ecosystems due to degradation of nodules can be mitigated by inoculation of nosZ+ and non-genetically modified organism nosZ++ strains of B. japonicum at a field scale.

  6. Role of Bradyrhizobium japonicum cytochrome c550 in nitrite and nitrate respiration.

    PubMed

    Bueno, Emilio; Bedmar, Eulogio J; Richardson, David J; Delgado, María J

    2008-02-01

    Bradyrhizobium japonicum cytochrome c(550), encoded by cycA, has been previously suggested to play a role in denitrification, the respiratory reduction of nitrate to dinitrogen. However, the exact role of this cytochrome in the denitrification process is unknown. This study shows that cytochrome c(550) is involved in electron transfer to the copper-containing nitrite reductase of B. japonicum, as revealed by the inability of a cycA mutant strain to consume nitrite and, consequently, to grow under denitrifying conditions with nitrite as the electron acceptor. Mutation of cycA had no apparent effect on methylviologen-dependent nitrite reductase activity. However, succinate-dependent nitrite reduction was largely inhibited, suggesting that c(550) is the in vivo electron donor to copper-containing nitrite reductase. In addition, this study demonstrates that a cytochrome c(550) mutation has a negative effect on expression of the periplasmic nitrate reductase. This phenotype can be rescued by extending the growth period of the cells. A model is proposed whereby a mutation in cycA reduces expression of the cbb(3)-type oxidase, affecting oxygen consumption rate by the cells and consequently preventing maximal expression of the periplasmic nitrate reductase during the first days of the growth period.

  7. An integrated biochemical system for nitrate assimilation and nitric oxide detoxification in Bradyrhizobium japonicum.

    PubMed

    Cabrera, Juan J; Salas, Ana; Torres, María J; Bedmar, Eulogio J; Richardson, David J; Gates, Andrew J; Delgado, María J

    2016-02-01

    Rhizobia are recognized to establish N2-fixing symbiotic interactions with legume plants. Bradyrhizobium japonicum, the symbiont of soybeans, can denitrify and grow under free-living conditions with nitrate (NO3 (-)) or nitrite (NO2 (-)) as sole nitrogen source. Unlike related bacteria that assimilate NO3 (-), genes encoding the assimilatory NO3 (-) reductase (nasC) and NO2 (-) reductase (nirA) in B. japonicum are located at distinct chromosomal loci. The nasC gene is located with genes encoding an ABC-type NO3 (-) transporter, a major facilitator family NO3 (-)/NO2 (-) transporter (NarK), flavoprotein (Flp) and single-domain haemoglobin (termed Bjgb). However, nirA clusters with genes for a NO3 (-)/NO2 (-)-responsive regulator (NasS-NasT). In the present study, we demonstrate NasC and NirA are both key for NO3 (-) assimilation and that growth with NO3 (-), but not NO2 (-) requires flp, implying Flp may function as electron donor to NasC. In addition, bjgb and flp encode a nitric oxide (NO) detoxification system that functions to mitigate cytotoxic NO formed as a by-product of NO3 (-) assimilation. Additional experiments reveal NasT is required for NO3 (-)-responsive expression of the narK-bjgb-flp-nasC transcriptional unit and the nirA gene and that NasS is also involved in the regulatory control of this novel bipartite assimilatory NO3 (-)/NO2 (-) reductase pathway.

  8. Characterization of Bradyrhizobium japonicum pcaBDC genes involved in 4-hydroxybenzoate degradation.

    PubMed

    Lorite, M J; Sanjuan, J; Velasco, L; Olivares, J; Bedmar, E J

    1998-05-11

    The pca structural genes encode enzymes that participate in the conversion of protocatechuate to succinate and acetylcoenzyme A. A 3. 05-kb region of the Bradyrhizobium japonicum strain USDA110 genome has been characterized, which contains the pcaB, pcaD and pcaC genes. The predicted protein sequences of the three genes have extensive homologies with beta-carboxy-cis,cis-muconate cycloisomerase (PcaB), beta-ketodiapate enol-lactone hydrolase (PcaD), and gamma-carboxymuconolactone decarboxylase (PcaC), respectively, from Acinetobacter calcoaceticus and Pseudomonas putida. The DNA sequence revealed that the pca genes are probably arranged in a single transcriptional unit, pcaBDC, similar to that described in P. putida. A pcaB deletion mutant constructed by marker exchange mutagenesis lost the ability to use 4-hydroxybenzoate or protocatechuate as the only carbon source, demonstrating functionality of the characterized genes in catabolism of hydroxyaromatics by B. japonicum. Furthermore, 4-hydroxybenzoate and protocatechuate became toxic for the pcaB mutant, indicating that hydroxyaromatics catabolism serves both nutritional and detoxifying purposes.

  9. Intra- and interspecies transfer and expression of Rhizobium japonicum hydrogen uptake genes and autotrophic growth capability

    PubMed Central

    Lambert, Grant R.; Cantrell, Michael A.; Hanus, F. Joe; Russell, Sterling A.; Haddad, Karen R.; Evans, Harold J.

    1985-01-01

    Cosmids containing hydrogen uptake genes have previously been isolated in this laboratory. Four new cosmids that contain additional hup gene(s) have now been identified by conjugal transfer of a Rhizobium japonicum 122DES gene bank into a Tn5-generated Hup- mutant and screening for the acquisition of Hup activity. The newly isolated cosmids, pHU50-pHU53, contain part of the previously isolated pHU1 but extend as far as 20 kilobases beyond its border. pHU52 complements five of six Hup- mutants and confers activity on several Hup- wild-type R. japonicum strains in the free-living state and where tested in nodules. Transconjugants obtained from interspecies transfer of pHU52 to Rhizobium meliloti 102F28, 102F32, and 102F51 and Rhizobium leguminosarum 128C53 showed hydrogen-dependent methyleneblue reduction, performed the oxyhydrogen reaction, and showed hydrogen-dependent autotrophic growth by virtue of the introduced genes. The identity of the presumptive transconjugants was confirmed by antibiotic-resistance profiles and by plant nodulation tests. Images PMID:16578786

  10. Chemical control of interstrain competition for soybean nodulation by Bradyrhizobium japonicum.

    PubMed Central

    Cunningham, S; Kollmeyer, W D; Stacey, G

    1991-01-01

    Previous research has shown that a significant limitation to the agricultural use of improved rhizobial inoculant strains is competition from the indigenous soil population. In this work, we sought to test whether chemical inhibitors of flavonoid-induced nod gene expression in Bradyrhizobium japonicum could be identified and utilized to affect interstrain competition for nodulation of soybeans. Approximately 1,000 structural and functional analogs of the known, natural inducers of nod gene expression were tested on six strains of B. japonicum containing a nodY-lacZ fusion. We successfully identified effective inhibitors of nodY expression. The addition of the inhibitor 7-hydroxy-5-methylflavone significantly inhibited nodulation by a sensitive strain and could be used to effectively manipulate the competition between strains for soybean nodulation. However, this work also uncovered significant limitations for the practical use of this methodology. For example, despite the almost universal induction response to the identified natural inducers, there was a wide variability among strains in their response to any specific inhibitor. Given this unexpected variability, the cost of registration of an agronomic chemical, and the potential for the development of resistant field populations, it is unlikely that chemical inhibitors can be successfully applied to a field situation. PMID:1892378

  11. [Iron regulation of gene expression in the Bradyrhizobium japonicum/soybean symbiosis]. Progress report

    SciTech Connect

    Guerinot, M.L.

    1992-06-01

    We wish to address the question of whether iron plays a regulatory role in the Bradyrhizobium japonicum/soybeam symbiosis. Iron may be an important regulatory signal in planta as the bacteria must acquire iron from their plant hosts and iron-containing proteins figure prominently in all nitrogen-fixing symbioses. For example, the bacterial partner is believed to synthesize the heme moiety of leghemoglobin, which may represent as much as 25--30% of the total soluble protein in an infected plant cell. For this reason, we have focused our attention on the regulation by iron of the first step in the bacterial heme biosynthetic pathway. The enzyme which catalyzes this step, 5-aminolevulinic acid synthase, is encoded by the hemA gene which we had previously cloned and sequenced. Specific objectives include: to define the cis-acting sequences which confer iron regulation on the B. japonicum hemA gene; to identify trans-acting factors which regulate the expression of hemA by iron; to identify new loci which are transcriptionally responsive to changes in iron availability; and to examine the effects of mutations in various known regulatory genes for their effect on the expression of hemA.

  12. (Iron regulation of gene expression in the Bradyrhizobium japonicum/soybean symbiosis)

    SciTech Connect

    Guerinot, M.L.

    1992-01-01

    We wish to address the question of whether iron plays a regulatory role in the Bradyrhizobium japonicum/soybeam symbiosis. Iron may be an important regulatory signal in planta as the bacteria must acquire iron from their plant hosts and iron-containing proteins figure prominently in all nitrogen-fixing symbioses. For example, the bacterial partner is believed to synthesize the heme moiety of leghemoglobin, which may represent as much as 25--30% of the total soluble protein in an infected plant cell. For this reason, we have focused our attention on the regulation by iron of the first step in the bacterial heme biosynthetic pathway. The enzyme which catalyzes this step, 5-aminolevulinic acid synthase, is encoded by the hemA gene which we had previously cloned and sequenced. Specific objectives include: to define the cis-acting sequences which confer iron regulation on the B. japonicum hemA gene; to identify trans-acting factors which regulate the expression of hemA by iron; to identify new loci which are transcriptionally responsive to changes in iron availability; and to examine the effects of mutations in various known regulatory genes for their effect on the expression of hemA.

  13. A novel mouse model of Schistosoma haematobium egg-induced immunopathology.

    PubMed

    Fu, Chi-Ling; Odegaard, Justin I; Herbert, De'Broski R; Hsieh, Michael H

    2012-01-01

    Schistosoma haematobium is the etiologic agent for urogenital schistosomiasis, a major source of morbidity and mortality for more than 112 million people worldwide. Infection with S. haematobium results in a variety of immunopathologic sequelae caused by parasite oviposition within the urinary tract, which drives inflammation, hematuria, fibrosis, bladder dysfunction, and increased susceptibility to urothelial carcinoma. While humans readily develop urogenital schistosomiasis, the lack of an experimentally-tractable model has greatly impaired our understanding of the mechanisms that underlie this important disease. We have developed an improved mouse model of S. haematobium urinary tract infection that recapitulates several aspects of human urogenital schistosomiasis. Following microinjection of purified S. haematobium eggs into the bladder wall, mice consistently develop macrophage-rich granulomata that persist for at least 3 months and pass eggs in their urine. Importantly, egg-injected mice also develop urinary tract fibrosis, bladder dysfunction, and various urothelial changes morphologically reminiscent of human urogenital schistosomiasis. As expected, S. haematobium egg-induced immune responses in the immediate microenvironment, draining lymph nodes, and systemic circulation are associated with a Type 2-dominant inflammatory response, characterized by high levels of interleukin-4, eosinophils, and IgE. Taken together, our novel mouse model may help facilitate a better understanding of the unique pathophysiological mechanisms of epithelial dysfunction, tissue fibrosis, and oncogenesis associated with urogenital schistosomiasis.

  14. An Isochore-Like Structure in the Genome of the Flatworm Schistosoma mansoni

    PubMed Central

    Lamolle, Guillermo; Protasio, Anna V.; Iriarte, Andrés; Jara, Eugenio; Simón, Diego; Musto, Héctor

    2016-01-01

    Eukaryotic genomes are compositionally heterogeneous, that is, composed by regions that differ in guanine–cytosine (GC) content (isochores). The most well documented case is that of vertebrates (mainly mammals) although it has been also noted among unicellular eukaryotes and invertebrates. In the human genome, regarded as a typical mammal, this heterogeneity is associated with several features. Specifically, genes located in GC-richest regions are the GC3-richest, display CpG islands and have shorter introns. Furthermore, these genes are more heavily expressed and tend to be located at the extremes of the chromosomes. Although the compositional heterogeneity seems to be widespread among eukaryotes, the associated properties noted in the human genome and other mammals have not been investigated in depth in other taxa. Here we provide evidence that the genome of the parasitic flatworm Schistosoma mansoni is compositionally heterogeneous and exhibits an isochore-like structure, displaying some features associated, until now, only with the human and other vertebrate genomes, with the exception of gene concentration. PMID:27435793

  15. Crystal structure of Schistosoma mansoni arginase, a potential drug target for the treatment of schistosomiasis.

    PubMed

    Hai, Yang; Edwards, Jennifer E; Van Zandt, Michael C; Hoffmann, Karl F; Christianson, David W

    2014-07-22

    The X-ray crystal structure of arginase from Schistosoma mansoni (SmARG) and the structures of its complexes with several amino acid inhibitors have been determined at atomic resolution. SmARG is a binuclear manganese metalloenzyme that catalyzes the hydrolysis of l-arginine to form l-ornithine and urea, and this enzyme is upregulated in all forms of the parasite that interact with the human host. Current hypotheses suggest that parasitic arginases could play a role in host immune evasion by depleting pools of substrate l-arginine that would otherwise be utilized for NO biosynthesis and NO-dependent processes in the immune response. Although the amino acid sequence of SmARG is only 42% identical with that of human arginase I, residues important for substrate binding and catalysis are strictly conserved. In general, classical amino acid inhibitors such as 2(S)-amino-6-boronohexanoic acid (ABH) tend to bind more weakly to SmARG than to human arginase I despite identical inhibitor binding modes in each enzyme active site. The identification of a patch on the enzyme surface capable of accommodating the additional Cα substitutent of an α,α-disubstituted amino acid inhibitor suggests that such inhibitors could exhibit higher affinity and biological activity. The structures of SmARG complexed with two different α,α-disubstituted derivatives of ABH are presented and provide a proof of concept for this approach in the enhancement of enzyme-inhibitor affinity.

  16. Mechanism of interaction of Salmonella and Schistosoma species.

    PubMed Central

    Melhem, R F; LoVerde, P T

    1984-01-01

    In endemic areas where Salmonella and Schistosoma species co-occur, several lines of evidence suggest a synergistic bacteria-parasite interaction that results in a protracted course for the salmonella infection that has proven difficult to diagnose and therapeutically remedy. In an in vitro system using a pilus-negative and a pilus-producing transductant strain of Salmonella typhimurium we show that pili are the ligands for bacterial adherence to the schistosome surface tegument. Antipili antibodies produced in rabbits against purified pili, purified and digested to monovalent (Fab) fragments, blocked the association of Salmonella sp. to the surface tegument of Schistosoma sp., further demonstrating that pili are the appendages necessary for bacteria-parasite surface interaction. The use of carbohydrates, lectins, and enzymes demonstrated that the bacteria-parasite surface interaction was specific, mediated by pili that specifically recognize and bind to mannose-like receptors, probably glycolipids, on the surface of the worms. We suggest that prolonged salmonellosis in schistosome-infected patients is due to an association of Salmonella sp. with the schistosome worms themselves and further that the schistosome worms provide a multiplication focus for these bacteria in the portal mesenteric system, with a persisting bacteremia following. PMID:6143728

  17. Effects of Cu on the content of chlorophylls and secondary metabolites in the Cu-hyperaccumulator lichen Stereocaulon japonicum.

    PubMed

    Nakajima, Hiromitsu; Hara, Kojiro; Yamamoto, Yoshikazu; Itoh, Kiminori

    2015-03-01

    Understanding the relationship between Cu and Cu-hyperaccumulator lichens is important for their application in monitoring and assessing heavy metal pollution. We investigated the Cu-hyperaccumulator lichen Stereocaulon japonicum at several Cu-polluted and control sites in Japan, and found the lichen to be widely distributed. Its concentrations of Cu, chlorophylls, and secondary metabolites, chlorophyll-related indices, and absorption spectra were measured, and we observed negative effects of Cu on these concentrations and indices. For highly Cu-polluted samples (>100ppm dry weight), however, we found significant linear correlations between Cu and chlorophyll concentrations. This can be considered as the response of the photobiont in S. japonicum to Cu stress. In highly Cu-polluted samples the chlorophyll-related indices and concentration of total secondary metabolites were almost constant regardless of Cu concentration. This suggests that the increase in chlorophyll concentration with the increase in Cu concentration enhances photosynthetic productivity per unit biomass, which will allow the production of extra structure and energy for maintaining the chlorophyll-related indices under Cu stress. The relationship between the increase in chlorophyll concentration of S. japonicum and the decrease in secondary metabolite concentration of the lichen can be explained by considering the balance of carbohydrates in the lichen. We found that a spectral index A372-A394 can be a useful index of the concentrations of Cu and total secondary metabolites in S. japonicum. These findings show the adjustment of the content of chlorophylls and secondary metabolites in S. japonicum to Cu stress, and provide a better understanding of the relationship between Cu and the Cu-hyperaccumulator lichen.

  18. Protective immunity to Schistosoma haematobium infection is primarily an anti-fecundity response stimulated by the death of adult worms

    PubMed Central

    Mitchell, Kate M.; Mutapi, Francisca; Savill, Nicholas J.; Woolhouse, Mark E.J.

    2012-01-01

    Protective immunity against human schistosome infection develops slowly, for reasons that are not yet fully understood. For many decades, researchers have attempted to infer properties of the immune response from epidemiological studies, with mathematical models frequently being used to bridge the gap between immunological theory and population-level data on schistosome infection and immune responses. Here, building upon earlier model findings, stochastic individual-based models were used to identify model structures consistent with observed field patterns of Schistosoma haematobium infection and antibody responses, including their distributions in cross-sectional surveys, and the observed treatment-induced antibody switch. We found that the observed patterns of infection and antibody were most consistent with models in which a long-lived protective antibody response is stimulated by the death of adult S. haematobium worms and reduces worm fecundity. These findings are discussed with regard to current understanding of human immune responses to schistosome infection. PMID:22847410

  19. Use of Geospatial Modeling to Predict Schistosoma mansoni Prevalence in Nyanza Province, Kenya

    PubMed Central

    Woodhall, Dana M.; Wiegand, Ryan E.; Wellman, Michael; Matey, Elizabeth; Abudho, Bernard; Karanja, Diana M. S.; Mwinzi, Pauline M. N.; Montgomery, Susan P.; Secor, W. Evan

    2013-01-01

    Background Schistosomiasis, a parasitic disease that affects over 200 million people, can lead to significant morbidity and mortality; distribution of single dose preventative chemotherapy significantly reduces disease burden. Implementation of control programs is dictated by disease prevalence rates, which are determined by costly and labor intensive screening of stool samples. Because ecological and human factors are known to contribute to the focal distribution of schistosomiasis, we sought to determine if specific environmental and geographic factors could be used to accurately predict Schistosoma mansoni prevalence in Nyanza Province, Kenya. Methodology/Principal Findings A spatial mixed model was fit to assess associations with S. mansoni prevalence in schools. Data on S. mansoni prevalence and GPS location of the school were obtained from 457 primary schools. Environmental and geographic data layers were obtained from publicly available sources. Spatial models were constructed using ArcGIS 10 and R 2.13.0. Lower S.mansoni prevalence was associated with further distance (km) to Lake Victoria, higher day land surface temperature (LST), and higher monthly rainfall totals. Altitude, night LST, human influence index, normalized difference vegetation index, soil pH, soil texture, soil bulk density, soil water capacity, population, and land use variables were not significantly associated with S. mansoni prevalence. Conclusions Our model suggests that there are specific environmental and geographic factors that influence S. mansoni prevalence rates in Nyanza Province, Kenya. Validation and use of schistosomiasis prevalence maps will allow control programs to plan and prioritize efficient control campaigns to decrease schistosomiasis burden. PMID:23977096

  20. Metal-specific control of gene expression mediated by Bradyrhizobium japonicum Mur and Escherichia coli Fur is determined by the cellular context.

    PubMed

    Hohle, Thomas H; O'Brian, Mark R

    2016-07-01

    Bradyrhizobium japonicum Mur and Escherichia coli Fur are manganese- and iron-responsive transcriptional regulators, respectively, that belong to the same protein family. Here, we show that neither Mur nor Fur discriminate between Fe(2+) and Mn(2+) in vitro nor is there a metal preference for conferral of DNA-binding activity on the purified proteins. When expressed in E. coli, B. japonicum Mur responded to iron, but not manganese, as determined by in vivo promoter occupancy and transcriptional repression activity. Moreover, E. coli Fur activity was manganese-dependent in B. japonicum. Total and chelatable iron levels were higher in E. coli than in B. japonicum under identical growth conditions, and Mur responded to iron in a B. japonicum iron export mutant that accumulated high levels of the metal. However, elevated manganese content in E. coli did not confer activity on Fur or Mur, suggesting a regulatory pool of manganese in B. japonicum that is absent in E. coli. We conclude that the metal selectivity of Mur and Fur depends on the cellular context in which they function, not on intrinsic properties of the proteins. Also, the novel iron sensing mechanism found in the rhizobia may be an evolutionary adaptation to the cellular manganese status.

  1. Molecular characterization of nosRZDFYLX genes coding for denitrifying nitrous oxide reductase of Bradyrhizobium japonicum.

    PubMed

    Velasco, Leonardo; Mesa, Socorro; Xu, Chang-Ai; Delgado, María J; Bedmar, Eulogio J

    2004-04-01

    The nosRZDFYLX gene cluster for the respiratory nitrous oxide reductase from Bradyrhizobium japonicum strain USDA110 has been cloned and sequenced. Seven protein coding regions corresponding to nosR, nosZ, the structural gene, nosD, nosF, nosY, nosL, and nosX were detected. The deduced amino acid sequence exhibited a high degree of similarity to other nitrous oxide reductases from various sources. The NosZ protein included a signal peptide for protein export. Mutant strains carrying either a nosZ or a nosR mutation accumulated nitrous oxide when cultured microaerobically in the presence of nitrate. Maximal expression of a P nosZ-lacZ fusion in strain USDA110 required simultaneously both low level oxygen conditions and the presence of nitrate. Microaerobic activation of the fusion required FixLJ and FixK(2).

  2. Assessment of voiding function in inhabitants infected with Schistosoma haematobium.

    PubMed

    Watanabe, Kanji; Muhoho, Ngethe D; Mutua, Wilfred R; Kiliku, Francis M; Awazawa, Toshiki; Moji, Kazuhiko; Aoki, Yoshiki

    2011-08-01

    Voiding function of Schistosoma haematobium infected students was evaluated in 45 schoolboys in Kwale district, Coast province, Kenya, using a questionnaire and uroflowmetry. Sixty-eight schoolboys who were S. haematobium negative were also examined. Symptoms related to the lower urinary tract were qualitatively assessed using the International Prostate Symptoms Score (I-PSS) questionnaire. The I-PSS showed that S. haematobium infected boys felt the need to strain to urinate and post voiding some urine still remained. To examine the disturbances revealed by I-PSS quantitatively, voiding was assessed by a portable uroflowmeter and a bladder scanner. Unexpectedly, no significant residual urine post voiding and no decline in urine flow rates were found in S. haematobium infected boys. However, volume-corrected maximum and average flow rates in S. haematobium infected boys were higher than in those not infected. These results suggest that cystitis associated with S. haematobium infection causes irritation and hypercontraction of the bladder.

  3. Transmission of Schistosoma mansoni in Rhino Camp, Uganda.

    PubMed

    Loroni-Lakwo, T; Odongo-Aginya, E I; Schweigmann, U; Schickerling, S; Lindner, D; Doehring-Schwerdtfeger, E

    1994-03-01

    Non-participant observations totalling 204 hours relevant to the transmission of Schistosoma mansoni infection were carried out in Rhino Camp at the shores of Albert Nile in North Uganda. A cross-sectional study of 636 individuals from Rhino Camp revealed a prevalence of S. mansoni infection of 77.8%. Occupational and domestic purposes were the most important reasons for water contact, whereas recreational purposes ranked lower and mainly concerned children. Both sexes were equally active in water contacts. A distinct preference of Nile water was noted despite availability of borehole water in the area. It is concluded that control measures against schistosomiasis have to take into consideration that water contact for recreational purposes might be minimized, whereas it is expected to be extremely difficult to reduce occupational and domestic water contacts.

  4. An integrated biochemical system for nitrate assimilation and nitric oxide detoxification in Bradyrhizobium japonicum

    PubMed Central

    Cabrera, Juan J.; Salas, Ana; Torres, María J.; Bedmar, Eulogio J.; Richardson, David J.; Gates, Andrew J.; Delgado, María J.

    2015-01-01

    Rhizobia are recognized to establish N2-fixing symbiotic interactions with legume plants. Bradyrhizobium japonicum, the symbiont of soybeans, can denitrify and grow under free-living conditions with nitrate (NO3−) or nitrite (NO2−) as sole nitrogen source. Unlike related bacteria that assimilate NO3−, genes encoding the assimilatory NO3− reductase (nasC) and NO2− reductase (nirA) in B. japonicum are located at distinct chromosomal loci. The nasC gene is located with genes encoding an ABC-type NO3− transporter, a major facilitator family NO3−/NO2− transporter (NarK), flavoprotein (Flp) and single-domain haemoglobin (termed Bjgb). However, nirA clusters with genes for a NO3−/NO2−-responsive regulator (NasS-NasT). In the present study, we demonstrate NasC and NirA are both key for NO3− assimilation and that growth with NO3−, but not NO2− requires flp, implying Flp may function as electron donor to NasC. In addition, bjgb and flp encode a nitric oxide (NO) detoxification system that functions to mitigate cytotoxic NO formed as a by-product of NO3− assimilation. Additional experiments reveal NasT is required for NO3−-responsive expression of the narK-bjgb-flp-nasC transcriptional unit and the nirA gene and that NasS is also involved in the regulatory control of this novel bipartite assimilatory NO3−/NO2− reductase pathway. PMID:26564204

  5. Host Plant Effects on Nodulation and Competitiveness of the Bradyrhizobium japonicum Serotype Strains Constituting Serocluster 123

    PubMed Central

    Cregan, P. B.; Keyser, H. H.; Sadowsky, M. J.

    1989-01-01

    Strains in Bradyrhizobium japonicum serocluster 123 are the major indigenous competitors for nodulation in a large portion of the soybean production area of the United States. Serocluster 123 is defined by the serotype strains USDA 123, USDA 127, and USDA 129. The objective of the work reported here was to evaluate the ability of two soybean genotypes, PI 377578 and PI 417566, to restrict the nodulation and reduce the competitiveness of serotype strains USDA 123, USDA 127, and USDA 129 in favor of the highly effective strain CB1809 and to determine how these soybean genotypes alter the competitive relationships among the three serotype strains in the serocluster. The soybean genotypes PI 377578 and PI 417566 along with the commonly grown cultivar Williams were planted in soil essentially free of soybean rhizobia and inoculated with single-strain treatments of USDA 123, USDA 127, USDA 129, or CB1809 and six dual-strain competition treatments of USDA 123, USDA 127, or USDA 129 versus CB1809, USDA 123 versus USDA 127, USDA 123 versus USDA 129, and USDA 127 versus USDA 129. PI 377578 severely reduced the nodulation and competitiveness of USDA 123 and USDA 127, while PI 417566 similarly affected the nodulation and competitiveness of USDA 129. Thus, the two soybean genotypes can reduce the nodulation and competitiveness of each of the three serocluster 123 serotype strains. Our results indicate that host control of restricted nodulation and reduced competitiveness is quite specific and effectively discriminates between B. japonicum strains which are serologically related. PMID:16348029

  6. Rhizobium japonicum mutants that are hypersensitive to repression of H2 uptake by oxygen.

    PubMed

    Maier, R J; Merberg, D M

    1982-04-01

    The synthesis of an H2 oxidation system in free-living Rhizobium japonicum wild-type strain SR is repressed by oxygen. Maximal H2 uptake rates were obtained in strain SR after derepression in 11 microM or less dissolved oxygen. Oxygen levels above 45 microM completely repressed H2 uptake in strain SR. Five R. japonicum mutant strains that are hypersensitive to repression or H2 oxidation by oxygen were derived from strain SR. The mutants were obtained by screening H2 uptake-negative mutants that retained the ability to oxidize H2 as bacteroids from soybean nodules. As bacteroids, the five mutant strains were capable of H2 oxidation rates comparable to that of the wild type. The mutants did not take up H2 when derepressed in 22 microM dissolved oxygen, whereas strain SR had substantial activity at this oxygen concentration. The O2 repression of H2 uptake in both the wild-type and two mutant strains, SR174 and SR200, was rapid and was similar to the effect of inhibiting synthesis of H2 uptake system components with rifampin. None of the mutant strains was able to oxidize H2 when the artificial electron acceptors methylene blue or phenazine methosulfate were provided. The mutant strains were not sensitive to killing by oxygen, they took up O2 at rates similar to strain SR, and they did not produce an H2 uptake system that was oxygen labile. Cyclic AMP levels were comparable in strain SR and the five mutant strains after subjection of the cultures to the derepression conditions.

  7. Rhizobium japonicum mutants that are hypersensitive to repression of H2 uptake by oxygen.

    PubMed Central

    Maier, R J; Merberg, D M

    1982-01-01

    The synthesis of an H2 oxidation system in free-living Rhizobium japonicum wild-type strain SR is repressed by oxygen. Maximal H2 uptake rates were obtained in strain SR after derepression in 11 microM or less dissolved oxygen. Oxygen levels above 45 microM completely repressed H2 uptake in strain SR. Five R. japonicum mutant strains that are hypersensitive to repression or H2 oxidation by oxygen were derived from strain SR. The mutants were obtained by screening H2 uptake-negative mutants that retained the ability to oxidize H2 as bacteroids from soybean nodules. As bacteroids, the five mutant strains were capable of H2 oxidation rates comparable to that of the wild type. The mutants did not take up H2 when derepressed in 22 microM dissolved oxygen, whereas strain SR had substantial activity at this oxygen concentration. The O2 repression of H2 uptake in both the wild-type and two mutant strains, SR174 and SR200, was rapid and was similar to the effect of inhibiting synthesis of H2 uptake system components with rifampin. None of the mutant strains was able to oxidize H2 when the artificial electron acceptors methylene blue or phenazine methosulfate were provided. The mutant strains were not sensitive to killing by oxygen, they took up O2 at rates similar to strain SR, and they did not produce an H2 uptake system that was oxygen labile. Cyclic AMP levels were comparable in strain SR and the five mutant strains after subjection of the cultures to the derepression conditions. PMID:6277861

  8. DNA Hybridization Probe for Use in Determining Restricted Nodulation among Bradyrhizobium japonicum Serocluster 123 Field Isolates

    PubMed Central

    Sadowsky, Michael J.; Cregan, Perry B.; Keyser, Harold H.

    1990-01-01

    Several soybean plant introduction (PI) genotypes have recently been described which restrict nodulation of Bradyrhizobium japonicum serocluster 123 in an apparently serogroup-specific manner. While PI 371607 restricts nodulation of strains in serogroup 123 and some in serogroup 127, those in serogroup 129 are not restricted. When DNA regions within and around the B. japonicum I-110 common nodulation genes were used as probes to genomic DNA from the serogroup strains USDA 123, USDA 127, and USDA 129, several of the probes differentially hybridized to the nodulation-restricted and -unrestricted strains. One of the gene regions, cloned in plasmid pMJS12, was subsequently shown to hybridize to 4.6-kilobase EcoRI fragments from DNAs from nodulation-restricted strains and to larger fragments in nodulation-unrestricted strains. To determine if the different hybridization patterns could be used to predict nodulation restriction, we hybridized pMJS12 to EcoRI-digested genomic DNAs from uncharacterized serocluster 123 field isolates. Of the 36 strains examined, 15 were found to have single, major, 4.6-kilobase hybridizing EcoRI fragments. When tested for nodulation, 80% (12 of 15) of the strains were correctly predicted to be restricted for nodulation of the PI genotypes. In addition, hybridization patterns obtained with pMJS12 and nodulation phenotypes on PI 371607 indicated that there are at least three types of serogroup 127 strains. Our results suggest that the pMJS12 gene probe may be useful in selecting compatible host-strain combinations and in determining the suitability of field sites for the placement of soybean genotypes containing restrictive nodulation alleles. Images PMID:16348217

  9. Quantitative Phosphoproteomic Analysis of Soybean Root Hairs Inoculated with Bradyrhizobium japonicum

    SciTech Connect

    Nguyen, Tran H.; Brechenmacher, Laurent; Aldrich, Joshua T.; Clauss, Therese RW; Gritsenko, Marina A.; Hixson, Kim K.; Libault, Marc; Tanaka, Kiwamu; Yang, Feng; Yao, Qiuming; Pasa-Tolic, Ljiljana; Xu, Dong; Nguyen, Henry T.; Stacey, Gary

    2012-11-11

    Root hairs are single hair-forming cells on roots that function to increase root surface area, enhancing water and nutrient uptake. In leguminous plants, root hairs also play a critical role as the site of infection by symbiotic nitrogen fixing rhizobia, leading to the formation of a novel organ, the nodule. The initial steps in the rhizobia-root hair infection process are known to involve specific receptor kinases and subsequent kinase cascades. Here, we characterize the phosphoproteome of the root hairs and the corresponding stripped roots (i.e., roots from which root hairs were removed) during rhizobial colonization and infection to gain insight into the molecular mechanism of root hair cell biology. We chose soybean (Glycine max L.), one of the most important crop plants in the legume family, for this study because of its larger root size, which permits isolation of sufficient root hair material for phosphoproteomic analysis. Phosphopeptides derived from root hairs and stripped roots, mock inoculated or inoculated with the soybean-specific rhizobium Bradyrhizobium japonicum, were labeled with the isobaric tag 8-plex ITRAQ, enriched using Ni-NTA magnetic beads and subjected to nRPLC-MS/MS analysis using HCD and decision tree guided CID/ETD strategy. A total of 1,625 unique phosphopeptides, spanning 1,659 non-redundant phosphorylation sites, were detected from 1,126 soybean phosphoproteins. Among them, 273 phosphopeptides corresponding to 240 phosphoproteins were found to be significantly regulated (>1.5 fold abundance change) in response to inoculation with B. japonicum. The data reveal unique features of the soybean root hair phosphoproteome, including root hair and stripped root-specific phosphorylation suggesting a complex network of kinase-substrate and phosphatase-substrate interactions in response to rhizobial inoculation.

  10. Praziquantel has no direct effect on (Na(+)+K+)-ATPases and (Ca2(+)-Mg2+)ATPases of Schistosoma mansoni.

    PubMed

    Cunha, V M; Noël, F

    1997-01-01

    Therapeutic concentrations of praziquantel produce a rapid and intense contraction of the human flatworm Schistosoma mansoni. As an action on ATPases responsible for calcium homeostasis arises as a possible explanation for the molecular mechanism of this effect, we tested here the effect of praziquantel on different preparations from male adult worms that were previously characterized for their content in (Na(+)+K+)-ATPase and (Ca2(+)-Mg2+)ATPase activities from different origins. Concentrations as high as 100 microM praziquantel did not inhibit (Na(+)+K+)-ATPase from tegument and carcass nor (Ca2(+)-Mg2+)ATPase from heterogeneous (P1) and microsomal (P4) fractions. As 100 microM praziquantel was also without effect on calcium permeability of microsomal vesicles actively loaded with 45Ca2+, the present results discard three hypotheses recently raised for the mechanism of praziquantel-induced contraction of S. mansoni.

  11. The genomic proliferation of transposable elements in colonizing populations: Schistosoma mansoni in the new world.

    PubMed

    Wijayawardena, Bhagya K; DeWoody, J Andrew; Minchella, Dennis J

    2015-06-01

    Transposable elements (TEs) are mobile genes with an inherent ability to move within and among genomes. Theory predicts that TEs proliferate extensively during physiological stress due to the breakdown of TE repression systems. We tested this hypothesis in Schistosoma mansoni, a widespread trematode parasite that causes the human disease schistosomiasis. According to phylogenetic analysis, S. mansoni invaded the new world during the last 500 years. We hypothesized that new world strains of S. mansoni would have more copies of TEs than old world strains due to the physiological stress associated with invasion of the new world. We quantified the copy number of six TEs (Saci-1, Saci-2 and Saci-3, Perere-1, Merlin-sm1, and SmTRC1) in the genome and the transcriptome of old world and new world strains of S. mansoni, using qPCR relative quantification. As predicted, the genomes of new world parasites contain significantly more copies of class I and class II TEs in both laboratory and field strains. However, such differences are not observed in the transcriptome suggesting that either TE silencing mechanisms have reactivated to control the expression of these elements or the presence of inactive truncated copies of TEs.

  12. Identification of Antigenic Glycans from Schistosoma mansoni by Using a Shotgun Egg Glycan Microarray

    PubMed Central

    Mickum, Megan L.; Prasanphanich, Nina Salinger; Song, Xuezheng; Dorabawila, Nelum; Mandalasi, Msano; Lasanajak, Yi; Luyai, Anthony; Secor, W. Evan; Wilkins, Patricia P.; Van Die, Irma; Smith, David F.; Nyame, A. Kwame

    2016-01-01

    Infection of mammals by the parasitic helminth Schistosoma mansoni induces antibodies to glycan antigens in worms and eggs, but the differential nature of the immune response among infected mammals is poorly understood. To better define these responses, we used a shotgun glycomics approach in which N-glycans from schistosome egg glycoproteins were prepared, derivatized, separated, and used to generate an egg shotgun glycan microarray. This array was interrogated with sera from infected mice, rhesus monkeys, and humans and with glycan-binding proteins and antibodies to gather information about the structures of antigenic glycans, which also were analyzed by mass spectrometry. A major glycan antigen targeted by IgG from different infected species is the FLDNF epitope [Fucα3GalNAcβ4(Fucα3)GlcNAc-R], which is also recognized by the IgG monoclonal antibody F2D2. The FLDNF antigen is expressed by all life stages of the parasite in mammalian hosts, and F2D2 can kill schistosomula in vitro in a complement-dependent manner. Different antisera also recognized other glycan determinants, including core β-xylose and highly fucosylated glycans. Thus, the natural shotgun glycan microarray of schistosome eggs is useful in identifying antigenic glycans and in developing new anti-glycan reagents that may have diagnostic applications and contribute to developing new vaccines against schistosomiasis. PMID:26883596

  13. Excretion/secretion products from Schistosoma mansoni adults, eggs and schistosomula have unique peptidase specificity profiles

    PubMed Central

    Dvořák, Jan; Fajtová, Pavla; Ulrychová, Lenka; Leontovyč, Adrian; Rojo-Arreola, Liliana; Suzuki, Brian M.; Horn, Martin; Mareš, Michael; Craik, Charles S.; Caffrey, Conor R.; O’Donoghue, Anthony J.

    2015-01-01

    Schistosomiasis is one of a number of chronic helminth diseases of poverty that severely impact personal and societal well-being and productivity. Peptidases (proteases) are vital to successful parasitism, and can modulate host physiology and immunology. Interference of peptidase action by specific drugs or vaccines can be therapeutically beneficial. To date, research on peptidases in the schistosome parasite has focused on either the functional characterization of individual peptidases or their annotation as part of global genome or transcriptome studies. We were interested in functionally characterizing the complexity of peptidase activity operating at the host-parasite interface, therefore the excretory-secretory products of key developmental stages of Schistosoma mansoni that parasitize the human were examined. Using class specific peptidase inhibitors in combination with a multiplex substrate profiling assay, a number of unique activities derived from endo- and exo-peptidases were revealed in the excretory-secretory products of schistosomula (larval migratory worms), adults and eggs. The data highlight the complexity of the functional degradome for each developmental stage of this parasite and facilitate further enquiry to establish peptidase identity, physiological and immunological function, and utility as drug or vaccine candidates. PMID:26409899

  14. Polymerase Chain Reaction: A Better Method for Diagnosing Chronic Schistosoma mansoni Infections.

    PubMed

    Abdel-Hafeez, Ekhlas Hamed; Mohamed, Rabie M; Belal, Usama S; Abdel-Raheem, Ehab M; Naoi, Koji; Norose, Kazumi

    2015-12-01

    For more effective diagnosis of the acute and chronic stages of Schistosoma mansoni infection in humans, the polymerase chain reaction (PCR) technique was compared with the Kato-Katz method. A total of 150 stool samples were collected from inpatient and outpatient clinics at the Department of Tropical Medicine, Minia University Hospital, Egypt. Three groups of patients, 50 with acute intestinal schistosomiasis, 70 with chronic intestinal schistosomiasis and 30 normal healthy controls were studied. Stool samples were analyzed by PCR and the Kato-Katz method. The mean number of eggs per gram of feces was 4.6 when estimated by the Kato-Katz method in positive stool samples from acute schistosomiasis cases but only 1.7 in chronic cases. In acute intestinal schistosomiasis, 15 and 45 out of 50 cases were positive by Kato-Katz and PCR, respectively. In the chronic intestinal schistosomiasis cases, 6 and 68 out of 70 cases were positive by the Kato-Katz and PCR methods, respectively. We conclude that PCR appears to be an effective diagnostic technique for S. mansoni infection, especially where a low worm burden exists, such as in chronic cases.

  15. Schistosoma mansoni: vaccination of mice with 10-krad-irradiated, cryopreserved schistosomules

    SciTech Connect

    Lewis, F.A.; Stirewalt, M.A.; Leef, J.L.

    1984-06-01

    Protection against a Schistosoma mansoni cercarial challenge was evaluated in mice immunized with a vaccine composed of 10-krad-irradiated, cryopreserved schistosomules. The level of resistance induced in C57B1/6 or NMRI (CV) mice increased with the number of schistosomules injected. Up to 83% reduction in challenge worm burden was achieved when 5000 schistosomules were injected per mouse. Intramuscular injection of the vaccine was superior to subcutaneous. Multiple immunizations, up to 3 at 4-week intervals, did not increase the resistance induced by a single immunization. A high level of protection developed in as little as 2 weeks and was maintained through at least 12 weeks postimmunization. The vaccine irradiated with 10 krad from either a 60-cobalt or 137-cesium source induced equivalent levels of resistance, and no differences were found in the immunogenicity of vaccines comprised of organisms irradiated as cercariae or as 1- to 3-hr-old schistosomules. These findings are basic to the development of a cryopreserved, live vaccine against schistosomiasis of humans or domestic animals.

  16. Flavonoids and Sesquiterpene Lactones from Artemisia absinthium and Tanacetum parthenium against Schistosoma mansoni Worms

    PubMed Central

    de Almeida, Luísa Maria Silveira; Gazolla, Matheus Coutinho; Silva Pinto, Pedro Luiz; da Silva, Marcos Paulo Nascimento; de Moraes, Josué

    2016-01-01

    Human schistosomiasis, caused by trematode worms of the genus Schistosoma, is one of the most significant neglected tropical diseases, affecting more than 200 million individuals worldwide and praziquantel is the only available drug to treat this disease. Artemisia absinthium L. and Tanacetum parthenium L. are species popularly used as anthelmintics. We investigated the in vitro schistosomicidal activity of crude extracts of A. absinthium (AA) and T. parthenium (TP) and their isolated compounds. AA and TP, at 200 μg/mL, were active, causing 100% mortality of all adult worms. Chromatographic fractionation of AA leads to isolation of artemetin and hydroxypelenolide, while santin, apigenin, and parthenolide were isolated from TP. Artemetin, hydroxypelenolide, santin, and apigenin, at 100 μM, were inactive against adult worms. Parthenolide (12.5 to 100 μM) caused 100% mortality, tegumental alterations, and reduction of motor activity of all adult worms of S. mansoni, without affecting mammalian cells. Confocal laser scanning microscopy showed tegumental morphological alterations and changes on the numbers of tubercles of S. mansoni worms. This report provides the first evidence for the in vitro activity of parthenolide against adult worms of S. mansoni, opening the route to further schistosomicidal studies with this compound. PMID:27980595

  17. Tandemly repeated exons encode 81-base repeats in multiple, developmentally regulated Schistosoma mansoni transcripts.

    PubMed Central

    Davis, R E; Davis, A H; Carroll, S M; Rajkovic, A; Rottman, F M

    1988-01-01

    The adult Schistosoma mansoni cDNA clone 10-3 encodes an antigen that is recognized by sera from infected humans. We characterized multiple developmentally regulated transcripts homologous to the 10-3 cDNA and portions of the complex genomic loci encoding those transcripts. Transcripts of approximately 950, 870, and 780 nucleotides were expressed in adults, whereas only the 780-nucleotide transcript was observed in the larval stage. These transcripts were highly similar, containing variable numbers of identical direct tandem repeats of 81 bases. Although the sequence of the repeating elements and sequences 3' to them were identical in all the transcripts, sequences 5' of the repeating elements exhibited variations, including a 27-base insertion, alternative start sites for transcription, and alternate 5' exon usage. These transcripts appeared to be derived in part by the developmentally controlled alternative splicing of small exons and the use of alternative transcription initiation sites from the one or two complex loci of at least 40 kilobase pairs. Each 81-base repeat in the transcripts was encoded by three dispersed 27-base-pair exons. These 27-base-pair exons were contained within highly conserved, reiterated 3-kilobase-pair genomic tandem arrays. Images PMID:3211127

  18. Towards an Understanding of the Function of the Phytochelatin Synthase of Schistosoma mansoni

    PubMed Central

    Rigouin, Coraline; Nylin, Elyse; Cogswell, Alexis A.; Schaumlöffel, Dirk; Dobritzsch, Dirk; Williams, David L.

    2013-01-01

    Phytochelatin synthase (PCS) is a protease-like enzyme that catalyzes the production of metal chelating peptides, the phytochelatins, from glutathione (GSH). In plants, algae, and fungi phytochelatin production is important for metal tolerance and detoxification. PCS proteins also function in xenobiotic metabolism by processing GSH S-conjugates. The aim of the present study is to elucidate the role of PCS in the parasitic worm Schistosoma mansoni. Recombinant S. mansoni PCS proteins expressed in bacteria could both synthesize phytochelatins and hydrolyze various GSH S-conjugates. We found that both the N-truncated protein and the N- and C-terminal truncated form of the enzyme (corresponding to only the catalytic domain) work through a thiol-dependant and, notably, metal-independent mechanism for both transpeptidase (phytochelatin synthesis) and peptidase (hydrolysis of GSH S-conjugates) activities. PCS transcript abundance was increased by metals and xenobiotics in cultured adult worms. In addition, these treatments were found to increase transcript abundance of other enzymes involved in GSH metabolism. Highest levels of PCS transcripts were identified in the esophageal gland of adult worms. Taken together, these results suggest that S. mansoni PCS participates in both metal homoeostasis and xenobiotic metabolism rather than metal detoxification as previously suggested and that the enzyme may be part of a global stress response in the worm. Because humans do not have PCS, this enzyme is of particular interest as a drug target for schistosomiasis. PMID:23383357

  19. Excretion/secretion products from Schistosoma mansoni adults, eggs and schistosomula have unique peptidase specificity profiles.

    PubMed

    Dvořák, Jan; Fajtová, Pavla; Ulrychová, Lenka; Leontovyč, Adrian; Rojo-Arreola, Liliana; Suzuki, Brian M; Horn, Martin; Mareš, Michael; Craik, Charles S; Caffrey, Conor R; O'Donoghue, Anthony J

    2016-03-01

    Schistosomiasis is one of a number of chronic helminth diseases of poverty that severely impact personal and societal well-being and productivity. Peptidases (proteases) are vital to successful parasitism, and can modulate host physiology and immunology. Interference of peptidase action by specific drugs or vaccines can be therapeutically beneficial. To date, research on peptidases in the schistosome parasite has focused on either the functional characterization of individual peptidases or their annotation as part of global genome or transcriptome studies. We were interested in functionally characterizing the complexity of peptidase activity operating at the host-parasite interface, therefore the excretory-secretory products of key developmental stages of Schistosoma mansoni that parasitize the human were examined. Using class specific peptidase inhibitors in combination with a multiplex substrate profiling assay, a number of unique activities derived from endo- and exo-peptidases were revealed in the excretory-secretory products of schistosomula (larval migratory worms), adults and eggs. The data highlight the complexity of the functional degradome for each developmental stage of this parasite and facilitate further enquiry to establish peptidase identity, physiological and immunological function, and utility as drug or vaccine candidates.

  20. Detection of Schistosoma mansoni circulating cathodic antigen for evaluation of resistance induced by irradiated cercariae.

    PubMed

    Barsoum, I S; Bogitsh, B J; Colley, D G

    1992-08-01

    The appearance of serum levels of circulating cathodic antigen (CCA) detectable by a monoclonal antibody (mAb) (5H11) antigen-capture sandwich enzyme-linked immunosorbent assay (ELISA) system was evaluated during acute Schistosoma mansoni infections in female CF1 mice exposed to either 100 or 25 cercariae. Measurable CCA levels occurred in these groups at 5 and 7 wk after infection, respectively. The kinetics of appearance of CCA were thus related to the intensity of infection. The level of resistance developed by female C57BL/6 mice upon immunization with irradiated cercariae, as expressed by both worm burden and CCA levels after cercarial challenge was evaluated. Immunization conferred 44% protection against the challenge infection, and the level of CCA detected in the sera of the control group was significantly (P less than 0.02) higher than that found in the sera of the immunized group, 6 wk after challenge. These results demonstrate that CCA detection by the 5H11 mAb antigen-capture sandwich ELISA can reflect vaccine-induced resistance against S. mansoni. Localization studies showed that 5H11 reacts with a CCA epitope in the adult worm gut and to a lesser extent with the male tegument. Adaptations of this and other antigen detection systems may prove useful in monitoring the efficacy of developmental vaccines, an ability that may be essential for the extension of such studies to humans.

  1. Development of Urinary Bladder Pre-Neoplasia by Schistosoma haematobium Eggs and Chemical Carcinogen in Mice

    PubMed Central

    Chala, Bayissa; Choi, Min-Ho; Moon, Kyung Chul; Kim, Hyung Suk; Kwak, Cheol; Hong, Sung-Tae

    2017-01-01

    Schistosoma haematobium is a biocarcinogen of human urinary bladder (UB). The present study investigated developing UB cancer mouse model by injecting S. haematobium eggs into the bladder wall and introduction of chemical carcinogens. Histopathological findings showed mild hyperplasia to epithelial vacuolar change, and high grade dysplasia. Squamous metaplasia was observed in the S. haematobium eggs+NDMA group at week 12 but not in other groups. Immunohistochemistry revealed significantly high expression of Ki-67 in urothelial epithelial cells of the S. haematobium eggs+BBN group at week 20. The qRT-PCR showed high expression of p53 gene in S. haematobium eggs group at week 4 and S. haematobium eggs+BBN group at week 20. E-cadherin and vimentin showed contrasting expression in S. haematobium eggs+BBN group. Such inverse expression of E-cadherin and vimentin may indicate epithelial mesenchymal transition in the UB tissue. In conclusion, S. haematobium eggs and nitrosamines may transform UB cells into squamous metaplasia and dysplasia in correlation with increased expression of Ki-67. Marked decrease in E-cadherin and increase in p53 and vimentin expressions may support the transformation. The present study introduces a promising modified animal model for UB cancer study using S. haematobium eggs. PMID:28285503

  2. Changes in the physiological and agricultural characteristics of peat-based Bradyrhizobium japonicum inoculants after long-term storage.

    PubMed

    Revellin, C; Meunier, G; Giraud, J J; Sommer, G; Wadoux, P; Catroux, G

    2000-08-01

    Commercial soybean inoculants processed with sterilised peat and stored at 20 degrees C for 1-8 years were used as experimental materials to assess the changes in the physiological activity of Bradyrhizobium japonicum after storage. Viable counts decreased and physiological characteristics of the bacterium changed during storage, with an increase in the time taken for colony appearance on a medium without yeast extract, an increase in the lag time for nodule appearance on soybean grown in glass tubes and a decrease in survival on seeds. All the inoculants produced a significant increase in grain yield in a field experiment. The percentage of efficient cells in the field (relative to the plate counts) decreased as the length of storage increased. These results suggest that the physiological activity of B. japonicum cells changes after storage. Practical implications for inoculant quality control are discussed.

  3. Characterization of the Bradyrhizobium japonicum galE gene: its impact on lipopolysaccharide profile and nodulation of soybean.

    PubMed

    Chang, Woo-Suk; Park, Kyoung-Min; Koh, Sung-Cheol; So, Jae-Seong

    2008-03-01

    The galE gene from Bradyrhizobium japonicum 61A101C, a soybean endosymbiont, was cloned and characterized. Its deduced amino-acid sequence showed a high similarity with that of other rhizobia. Functional identification of the galE gene was achieved by complementation of a galE mutant strain, PL2, with a series of pKM subclones. Disruption of the B. japonicum galE gene affects the lipopolysaccharide profile compared with that of the wild type, suggesting that galE is responsible for alteration of lipopolysaccharide structure. Examination of nodule formation by the wild-type and galE mutant revealed that the former displayed normal nodule development on soybean roots, whereas the latter showed no nodule formation at all time points examined except for 20 days after inoculation when <10% of soybean formed pseudo-nodules.

  4. The Bradyrhizobium japonicum napEDABC genes encoding the periplasmic nitrate reductase are essential for nitrate respiration.

    PubMed

    Delgado, María J; Bonnard, Nathalie; Tresierra-Ayala, Alvaro; Bedmar, Eulogio J; Müller, Peter

    2003-12-01

    The napEDABC gene cluster that encodes the periplasmic nitrate reductase from Bradyrhizobium japonicum USDA110 has been isolated and characterized. napA encodes the catalytic subunit, and the napB and napC gene products are predicted to be a soluble dihaem c and a membrane-anchored tetrahaem c-type cytochrome, respectively. napE encodes a transmembrane protein of unknown function, and the napD gene product is a soluble protein which is assumed to play a role in the maturation of NapA. Western blots of the periplasmic fraction from wild-type cells grown anaerobically with nitrate revealed the presence of a protein band with a molecular size of about 90 kDa corresponding to NapA. A B. japonicum mutant carrying an insertion in the napA gene was unable to grow under nitrate-respiring conditions, lacked nitrate reductase activity, and did not show the 90 kDa protein band. Complementation of the mutant with a plasmid bearing the napEDABC genes restored both nitrate-dependent anaerobic growth of the cells and nitrate reductase activity. A membrane-bound and a periplasmic c-type cytochrome, with molecular masses of 25 kDa and 15 kDa, respectively, were not detected in the napA mutant strain incubated anaerobically with nitrate, which identifies those proteins as the NapC and the NapB components of the B. japonicum periplasmic nitrate reductase enzyme. These results suggest that the periplasmic nitrate reductase is the enzyme responsible for anaerobic growth of B. japonicum under nitrate-respiring conditions. The promoter region of the napEDABC genes has been characterized by primer extension. A major transcript initiates 66.5 bp downstream of the centre of a putative FNR-like binding site.

  5. Radiology corner. Answer to last month's radiology case and images: Schistosomiasis japonicum involving the liver and colon.

    PubMed

    Ly, Justin Q; Sanders, Timothy G; Folio, Les

    2007-02-01

    Abdominal radiography showed subtle curvilinear densities overlying the left lower quadrant and central within the pelvis (Fig. 1a). This was confirmed on intravenous contrast-enhanced abdominopelvic CT to be caused by thin mucosal surface calcifications within the descending and sigmoid colons (Fig. 1b, c). Incidental note is made of thin right hepatic lobe capsule calcifications (Fig. 1d). These colonic and hepatic calcifications are characteristic of Schistosomiasis infection of the gastrointestinal tract. Liver biopsy confirmed Schistosomiasis japonicum infection.

  6. [Dynamic transmission of Schistosoma by Biomphalaria pfeifferi in the region of Man in Côte d'Ivoire].

    PubMed

    Yapi Yapi, G; Touré, M; Boka, O M; Tia, E; Boby, O A-M

    2014-12-01

    Intestinal schistosomiasis by Schistosoma mansoni is a parasitary affection transmitted in West Africa by the mollusc Biomphalaria pfeifferi. Transmission dynamic of schistosomiasis by Biomphalaria pfeifferi has seldom been investigated in Côte d'Ivoire. In the framework of a research project on the epidemiology of schistosomiasis in the natural forest ecosystems, this study was performed longitudinally over a period of three years in Man region, in western Côte d'Ivoire. The trial set up from 1986 to 1989 and the project was funded by the World Health Organization. The general objective is to design a strategy of schistosomiasis control based on chemotherapy. The approach aims at interrupting or considerably reducing the reinfections, prolonging in that way the duration of the positive effects of the chemotherapy. The specific objectives assigned to the work consisted in studying the dynamic of the B. pfeifferi population and the infection of B. pfeifferi. To achieve our objectives, diverse methods (i: the molluscs sampling by two prospectors during 15 minutes per study site and ii: individual isolation of molluscs in test tubes with 5 or 10 mL of filtered water and exposure to light) have been used. They enabled us in the sampling of the intermediary host molluscs of Schistosoma and seek their infections. The results show that apparent high densities of B. pfeifferi can be observed at the end of the dry season and at the beginning of rainy seasons. In addition, the variation of relative abundance of intermediary host molluscs of Schistosoma is significantly influenced by rainfall and the system of water ways. The period of transmission of the infection to man is six months at Gueupleu village and ten months at Botonguiné village. In order to optimize the effect of chemotherapy in these sites of transmission characterized by a high level of endemy (68 %), an extreme mobility of human populations and a multiplicity of contamination sites, this study should not

  7. A genetically distinct Schistosoma from Radix luteola from Nepal related to Schistosoma turkestanicum: A phylogenetic study of schistosome and snail host.

    PubMed

    Devkota, Ramesh; Brant, Sara V; Loker, Eric S

    2016-12-01

    During a survey of freshwater snails in the Terai region of southern Nepal, 16 of 2588 specimens of Radix luteola from 4 different habitats were found to be shedding schistosome cercariae. None of the 1411 specimens of Radix acuminata we collected were positive for schistosomes. Analysis of 28S, cox1, 16S and 12S sequences indicated that all the R. luteola-derived schistosomes were genetically very similar to one another and, although unambiguously grouping most closely to the widespread Asian species Schistosoma turkestanicum, were clearly genetically distinct from it. We lack information from other life cycle stages to verify the specific identity of these cercariae, but it is possible they are of Schistosoma bomfordi or Schistosoma dattai, both species previously known only from northern India, the latter species known to infect R. luteola. This study provides sequence evidence for a third genetically distinct lymnaeid-transmitted Schistosoma lineage in Asia (to go along with S. turkestanicum and S. incognitum). As a close relative of S. turkestanicum, it provides the first direct molecular evidence to accompany morphological results from earlier studies for the presence of a S. turkestanicum species group in Asia. It increases to five the number of known or suspected mammalian schistosome species to be present in the Terai region of Nepal. Radix luteola and R. acuminata were identified and differentiated using conchological features and by molecular phylogenetic analyses of cox1 and 16S genes.

  8. Cloning and Mutagenesis of a Cytochrome P-450 Locus from Bradyrhizobium japonicum That Is Expressed Anaerobically and Symbiotically

    PubMed Central

    Tully, Raymond E.; Keister, Donald L.

    1993-01-01

    Cytochromes P-450, which in many organisms participate in the metabolism of a variety of endobiotic and xenobiotic substances, are synthesized by symbiotic bacteroids of Bradyrhizobium japonicum. Polyclonal antibodies were raised against two cytochromes P-450 (CYP112 and CYP114) purified from bacteroids. A lambda gt11 expression clone of B. japonicum USDA 110 DNA that reacted with the anti-CYP112 antibody was obtained and was used to screen a library of USDA 110 genomic DNA in pLAFR1 for a clone of the P-450 locus. Forced expression of subclones of the P-450 locus in Escherichia coli produced polypeptides that reacted with either the anti-CYP112 antibody or the anti-CYP114 antibody; no cross-reactivity was evident. A Western blot (immunoblot) analysis showed that neither protein was present in free-living aerobically grown B. japonicum cells, but that both proteins were present in cells grown anaerobically, as well as in bacteroids. A mutant strain disrupted in the CYP112 locus produced neither CYP112 nor CYP114, indicating that the mutation was polar for CYP114. The mutant produced effective nodules on soybeans, even though the bacteroids contained no detectable P-450. This suggests that the cytochromes P-450 which we examined are not involved in an essential symbiotic function. Images PMID:16349113

  9. Local Auxin Biosynthesis Mediated by a YUCCA Flavin Monooxygenase Regulates Haustorium Development in the Parasitic Plant Phtheirospermum japonicum[OPEN

    PubMed Central

    Takebayashi, Yumiko; Kasahara, Hiroyuki; Wafula, Eric; dePamphilis, Claude W.; Namba, Shigetou

    2016-01-01

    Parasitic plants in the Orobanchaceae cause serious agricultural problems worldwide. Parasitic plants develop a multicellular infectious organ called a haustorium after recognition of host-released signals. To understand the molecular events associated with host signal perception and haustorium development, we identified differentially regulated genes expressed during early haustorium development in the facultative parasite Phtheirospermum japonicum using a de novo assembled transcriptome and a customized microarray. Among the genes that were upregulated during early haustorium development, we identified YUC3, which encodes a functional YUCCA (YUC) flavin monooxygenase involved in auxin biosynthesis. YUC3 was specifically expressed in the epidermal cells around the host contact site at an early time point in haustorium formation. The spatio-temporal expression patterns of YUC3 coincided with those of the auxin response marker DR5, suggesting generation of auxin response maxima at the haustorium apex. Roots transformed with YUC3 knockdown constructs formed haustoria less frequently than nontransgenic roots. Moreover, ectopic expression of YUC3 at the root epidermal cells induced the formation of haustorium-like structures in transgenic P. japonicum roots. Our results suggest that expression of the auxin biosynthesis gene YUC3 at the epidermal cells near the contact site plays a pivotal role in haustorium formation in the root parasitic plant P. japonicum. PMID:27385817

  10. Local Auxin Biosynthesis Mediated by a YUCCA Flavin Monooxygenase Regulates Haustorium Development in the Parasitic Plant Phtheirospermum japonicum.

    PubMed

    Ishida, Juliane K; Wakatake, Takanori; Yoshida, Satoko; Takebayashi, Yumiko; Kasahara, Hiroyuki; Wafula, Eric; dePamphilis, Claude W; Namba, Shigetou; Shirasu, Ken

    2016-08-01

    Parasitic plants in the Orobanchaceae cause serious agricultural problems worldwide. Parasitic plants develop a multicellular infectious organ called a haustorium after recognition of host-released signals. To understand the molecular events associated with host signal perception and haustorium development, we identified differentially regulated genes expressed during early haustorium development in the facultative parasite Phtheirospermum japonicum using a de novo assembled transcriptome and a customized microarray. Among the genes that were upregulated during early haustorium development, we identified YUC3, which encodes a functional YUCCA (YUC) flavin monooxygenase involved in auxin biosynthesis. YUC3 was specifically expressed in the epidermal cells around the host contact site at an early time point in haustorium formation. The spatio-temporal expression patterns of YUC3 coincided with those of the auxin response marker DR5, suggesting generation of auxin response maxima at the haustorium apex. Roots transformed with YUC3 knockdown constructs formed haustoria less frequently than nontransgenic roots. Moreover, ectopic expression of YUC3 at the root epidermal cells induced the formation of haustorium-like structures in transgenic P. japonicum roots. Our results suggest that expression of the auxin biosynthesis gene YUC3 at the epidermal cells near the contact site plays a pivotal role in haustorium formation in the root parasitic plant P. japonicum.

  11. Practical application of methanol-mediated mutualistic symbiosis between Methylobacterium species and a roof greening moss, Racomitrium japonicum.

    PubMed

    Tani, Akio; Takai, Yuichiro; Suzukawa, Ikko; Akita, Motomu; Murase, Haruhiko; Kimbara, Kazuhide

    2012-01-01

    Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production.

  12. Central nervous system of Chaetoderma japonicum (Caudofoveata, Aplacophora): implications for diversified ganglionic plans in early molluscan evolution.

    PubMed

    Shigeno, Shuichi; Sasaki, Takenori; Haszprunar, Gerhard

    2007-10-01

    The organization of the central nervous system of an "aplacophoran" mollusc, Chaetoderma japonicum, is described as a means to understand a primitive condition in highly diversified molluscan animals. This histological and immunocytochemical study revealed that C. japonicum still retains a conservative molluscan tetra-neural plan similar to those of neomenioids, polyplacophorans, and tryblidiids. However, the ventral and lateral nerve cords of C. japonicum are obviously ganglionated to various degrees, and the cerebral cord-like ganglia display a lobular structure. The putative chemosensory networks are developed, being composed of sensory cells of the oral shield, eight precerebral ganglia, and eight neuropil compartments that form distinct masses of neurites. In the cerebral cord-like ganglia, three anterior, posterior, and dorsal lobes are distinguished with well-fasciculated tracts in their neuropils. Most neuronal somata are uniform in size, and no small globuli-like cell clusters are found; however, localized serotonin-like immunoreactivity and acetylated tubulin-containing tracts suggest the presence of functional subdivisions. These complicated morphological features may be adaptive structures related to the specialized foraminiferan food in muddy bottoms. Based on a comparative scheme in basal molluscan groups, we characterize an independent evolutionary process for the unique characters of the central nervous systems of chaetoderms.

  13. The Bradyrhizobium japonicum nolA gene and its involvement in the genotype-specific nodulation of soybeans.

    PubMed Central

    Sadowsky, M J; Cregan, P B; Gottfert, M; Sharma, A; Gerhold, D; Rodriguez-Quinones, F; Keyser, H H; Hennecke, H; Stacey, G

    1991-01-01

    Several soybean genotypes have been identified which specifically exclude nodulation by members of Bradyrhizobium japonicum serocluster 123. We have identified and sequenced a DNA region from B. japonicum strain USDA 110 which is involved in genotype-specific nodulation of soybeans. This 2.3-kilobase region, cloned in pMJS12, allows B. japonicum serocluster 123 isolates to form nodules on plants of serogroup 123-restricting genotypes. The nodules, however, were ineffective for symbiotic nitrogen fixation. The nodulation-complementing region is located approximately 590 base pairs transcriptionally downstream from nodD2. The 5' end of pMJS12 contains a putative open reading frame (ORF) of 710 base pairs, termed nolA. Transposon Tn3-HoHo mutations only within the ORF abolished nodulation complementation. The N terminus of the predicted nolA gene product has strong similarity with the N terminus of MerR, the regulator of mercury resistance genes. Translational lacZ fusion experiments indicated that nolA was moderately induced by soybean seed extract and the isoflavone genistein. Restriction fragments that hybridize to pMJS12 were detected in genomic DNAs from both nodulation-restricted and -unrestricted strains. PMID:1988958

  14. A novel genetic locus outside the symbiotic island is required for effective symbiosis of Bradyrhizobium japonicum with soybean Glycine max.

    PubMed

    Becker, Bernd Ulrich; Bonnard, Nathalie; Boiffin, Vincent; Mörschel, Erhard; Tresierra, Alvaro; Müller, Peter

    2004-11-01

    In order to investigate the symbiotic interaction between soybean and Bradyrhizobium japonicum, TnphoA mutagenesis of the microsymbiont was performed. Mutant strain 2-10 was found to induce a strongly reduced number of ineffective nodules. Ultrastructural analysis of the soybean nodule central tissue revealed the presence of numerous starch granules and vacuoles in the infected cells. In addition, the number of symbiosomes was extremely low, indicating an impaired interaction between the plant and invading bacteria. Cloning and sequencing of the mutated DNA region uncovered four open reading frames (ORFs) lacking any data base similarities. ORFs srrA1 and srrA2, the 2-10 TnphoA insertion site, are encoded in the same reading frame. A 35-kDa expression product in Escherichia coli indicated the presence of a common protein, called SrrA (symbiotically relevant region) in B. japonicum 110spc4, encoded by combined srrA1 and srrA2 genes. The analysis of gene disruption mutants revealed that srrB and srrC were also required for effective symbiosis with soybeans. Further downstream the gene for a putative inner membrane protein (pipA) of unknown function was encoded on the opposite strand. Primer extension studies led to the conclusion that the organization of genes differed from the RhizoBase annotation in this particular region of B. japonicum USDA110.

  15. Variation in the Frequency and Extent of Hybridization between Leucosceptrum japonicum and L. stellipilum (Lamiaceae) in the Central Japanese Mainland

    PubMed Central

    Li, Yue; Maki, Masayuki

    2015-01-01

    Variations in the frequency and extent of hybridization among mixed populations located in the same contact zone provide natural laboratories for the study of extrinsic reproductive isolation maintaining species integrity. In this study, we examined the pattern of hybridization between L. japonicum and L. stellipilum among mixed populations in different localities of a contact zone. The genetic structures from three sympatric populations and six mixed populations in the hybrid zone, and five reference populations far from the contact zone, were characterized using 10 neutral nuclear microsatellite markers. Evidence from genetic distance-based clustering analysis, the frequency distribution of admixture proportion values, and the hybrid category assignment approaches indicated that the frequency and extent of hybridization varied considerably among populations in the contact zone between L. japonicum and L. stellipilum. One likely explanation is that variation in exogenous (ecological) selection among populations might contribute to differences in frequency and extent of hybridization. The present study will facilitate future research exploring the evolution of reproductive isolation between L. japonicum and L. stellipilum. PMID:25738505

  16. Practical Application of Methanol-Mediated Mutualistic Symbiosis between Methylobacterium Species and a Roof Greening Moss, Racomitrium japonicum

    PubMed Central

    Tani, Akio; Takai, Yuichiro; Suzukawa, Ikko; Akita, Motomu; Murase, Haruhiko; Kimbara, Kazuhide

    2012-01-01

    Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production. PMID:22479445

  17. Antioxidant, α-glucosidase inhibitory and anti-inflammatory effects of aerial parts extract from Korean crowberry (Empetrum nigrum var. japonicum)

    PubMed Central

    Hyun, Tae Kyung; Kim, Hyoun-Chol; Ko, Yeong-Jong; Kim, Ju-Sung

    2015-01-01

    Crowberry (Empetrum nigrum L.) is a wild berry commonly found in the northern hemisphere. Crowberry fruits have been suggested as good resources for functional applications in the cosmetic and pharmaceutical industries, but the high polyphenolic content in crowberry leaves also indicates crowberry aerial parts as potential dietary health supplements. In this study, therefore, the biological activities of the aerial parts of Korean crowberry (E. nigrum var. japonicum) were investigated. Antioxidant activity was measured by three different assays on DPPH free radical scavenging, reducing power, and total antioxidant capacities. Dose-dependent antioxidant activities were exhibited by crude methanol extract and its fractions, suggesting that the crude methanol extract and EtOAc fraction possessed strong antioxidant activities and capacities. In addition, the crude methanol extract and EtOAc strongly inhibited α-glucosidase activity and suppressed the secretion of pro-inflammatory mediator and nitrite oxide from LPS-stimulated RAW 264.7 cells. These findings provide valuable evidence for the potential of such parts as good dietary sources of natural antioxidant, α-glucosidase inhibitory, and anti-inflammatory components, suggesting that using the non-edible parts (e.g., leaves and stems) of crowberry can be a potential natural avenue for improving human health. PMID:26980998

  18. Schistosoma mansoni: assessment of effects of oleic acid, cercarial age and water temperature on parasite-host attraction.

    PubMed

    Lee, Vivien S T; Burgess, Jefferey L; Sterling, Charles R; Lutz, Eric A

    2013-09-01

    Although the lifecycle of Schistosoma spp. and pathophysiology of schistosomiasis have been established, the mechanism by which cercariae find their host is not well understood. Speculatively, host infection by random and accidental host contact is not as biologically plausible as a biochemical mechanism of mammalian attraction. A few studies have indicated that biochemical cues and temperature gradients may play a role in host identification, attraction and attachment triggers. This study aimed to elucidate these mechanisms more specifically through evaluation of biochemical, age and temperature influences leading to Schistosoma mansoni cercariae attraction and attachment behaviors. Oleic acid, a common unsaturated free fatty acid in the outer layer of human skin, was tested for cercariae attraction across biologically relevant concentrations. Influence of media type (beeswax, nail varnish and agar), age-dependent behavior variability and environmentally appropriate temperatures (22 and 30 °C) were also evaluated. Results indicated that oleic acid at concentrations of 0.3, 0.9 and 1.8 g/mL in beeswax significantly increased median attachment to media (median attachment of 7.50%, 4.20% and 3.71%, respectively, P<0.001), compared with plain beeswax, with maximal attachment of 30.30% at 0.3g/mL of oleic acid. In media containing 0.3 g/mL of oleic acid, cercarial attachment was highest for freshly emerged cercariae to 5h post-emergence, with a significant decrease in attachment behavior at 10h post-emergence (P<0.01). Aquatic temperature at which cercariae were exposed to media did not yield significant results (P value >0.05). Biochemical, age and environmental factors influencing cercarial host attraction and attachment behavior have been elucidated by this study. This information will inform further development of devices for environmental surveillance and potentially improve cercarial exposure prevention strategies.

  19. Schistosoma mansoni experimental infection in Mus spretus (SPRET/EiJ strain) mice

    PubMed Central

    Pérez del Villar, Luis; Vicente, Belén; Galindo-Villardón, Purificación; Castellanos, Andrés; Pérez-Losada, Jesús; Muro, Antonio

    2013-01-01

    Most Schistosoma mansoni experimental infections are developed in several inbred strains of Mus musculus as definitive host. In contrast, Mus spretus is unexplored in Schistosoma infection studies. Mus spretus provides a high variation of immunological phenotypes being an invaluable tool for genetic studies and gene mapping. The aim of this study is to characterize hematological and immunological responses against Schistosoma mansoni infection in Mus spretus (SPRET/EiJ strain) vs. Mus musculus (CD1 strain) mice. Nine weeks after cercarial exposure, animals were perfused and the parasite burden was assessed. The parasitological data suggests that SPRET/EiJ mice tolerate higher parasite loads compared to CD1 strain. In addition, hematological parameters measured in Mus spretus group showed a significant increase in granulocytes population in early stages of infection compared to the CD1 cohort. Meanwhile, CD1 presented higher levels of lymphocytes and IgG1 in the late stages of S. mansoni experimental infection. PMID:23985166

  20. Recent advances in the diagnosis of Schistosoma infection: the detection of parasite DNA.

    PubMed

    Rabello, Ana; Pontes, Luís André; Dias-Neto, Emmanuel

    2002-01-01

    As Schistosoma sp. control programs are chiefly based on treatment of infected population, adequate case finding has a crucial role. The available diagnostic methods are far from ideal, since the search for eggs in stools and the detection of circulating antigens lack sensitivity in low prevalence and post-treatment situations and antibody detection lacks specificity. In most endemic foci, repeated treatment of infected people leaves a number of non-diagnosed and consequently non-treated persons, enough to maintain a persistent residue of 5 to 10% prevalence. In an attempt to surpass these diagnostic limitations we have developed a polymerase chain reaction (PCR) for the detection of Schistosoma sp. in feces that, in a first population study, has shown to be more sensitive than three-repeated stool Kato-Katz examination. The PCR may constitute a valuable tool for the diagnosis of the Schistosoma sp. infection in special situations, when high sensitivity and specificity are required and infrastructure is available.

  1. Early Detection of Schistosoma Egg–Induced Pulmonary Granulomas in a Returning Traveler

    PubMed Central

    Coron, Noémie; Le Govic, Yohann; Kettani, Sami; Pihet, Marc; Hemery, Sandrine; de Gentile, Ludovic; Chabasse, Dominique

    2016-01-01

    We report the case of a French traveler who developed acute pulmonary schistosomiasis 2 months after visiting Benin. He presented with a 1-month history of fever, cough, and thoracic pain. Initial investigations revealed hypereosinophilia and multiple nodular lesions on chest computed tomography scan. Lung biopsies were performed 2 months later because of migrating chest infiltrates and increasing eosinophilia. Histological examination showed schistosomal egg–induced pulmonary granulomas with ova exhibiting a prominent terminal spine, resembling Schistosoma haematobium. However, egg shells were Ziehl–Neelsen positive, raising the possibility of a Schistosoma intercalatum or a Schistosoma guineensis infection. Moreover, involvement of highly infectious hybrid species cannot be excluded considering the atypical early pulmonary oviposition. This case is remarkable because of the rarity of pulmonary schistosomiasis, its peculiar clinical presentation and difficulties in making species identification. It also emphasizes the need to consider schistosomiasis diagnosis in all potentially exposed travelers with compatible symptoms. PMID:26787142

  2. Small Open Reading Frames, Non-Coding RNAs and Repetitive Elements in Bradyrhizobium japonicum USDA 110

    PubMed Central

    Hahn, Julia; Tsoy, Olga V.; Thalmann, Sebastian; Čuklina, Jelena; Gelfand, Mikhail S.

    2016-01-01

    Small open reading frames (sORFs) and genes for non-coding RNAs are poorly investigated components of most genomes. Our analysis of 1391 ORFs recently annotated in the soybean symbiont Bradyrhizobium japonicum USDA 110 revealed that 78% of them contain less than 80 codons. Twenty-one of these sORFs are conserved in or outside Alphaproteobacteria and most of them are similar to genes found in transposable elements, in line with their broad distribution. Stabilizing selection was demonstrated for sORFs with proteomic evidence and bll1319_ISGA which is conserved at the nucleotide level in 16 alphaproteobacterial species, 79 species from other taxa and 49 other Proteobacteria. Further we used Northern blot hybridization to validate ten small RNAs (BjsR1 to BjsR10) belonging to new RNA families. We found that BjsR1 and BjsR3 have homologs outside the genus Bradyrhizobium, and BjsR5, BjsR6, BjsR7, and BjsR10 have up to four imperfect copies in Bradyrhizobium genomes. BjsR8, BjsR9, and BjsR10 are present exclusively in nodules, while the other sRNAs are also expressed in liquid cultures. We also found that the level of BjsR4 decreases after exposure to tellurite and iron, and this down-regulation contributes to survival under high iron conditions. Analysis of additional small RNAs overlapping with 3’-UTRs revealed two new repetitive elements named Br-REP1 and Br-REP2. These REP elements may play roles in the genomic plasticity and gene regulation and could be useful for strain identification by PCR-fingerprinting. Furthermore, we studied two potential toxin genes in the symbiotic island and confirmed toxicity of the yhaV homolog bll1687 but not of the newly annotated higB homolog blr0229_ISGA in E. coli. Finally, we revealed transcription interference resulting in an antisense RNA complementary to blr1853, a gene induced in symbiosis. The presented results expand our knowledge on sORFs, non-coding RNAs and repetitive elements in B. japonicum and related bacteria. PMID

  3. Effect of clinically approved HDAC inhibitors on Plasmodium, Leishmania and Schistosoma parasite growth.

    PubMed

    Chua, Ming Jang; Arnold, Megan S J; Xu, Weijun; Lancelot, Julien; Lamotte, Suzanne; Späth, Gerald F; Prina, Eric; Pierce, Raymond J; Fairlie, David P; Skinner-Adams, Tina S; Andrews, Katherine T

    2017-04-01

    Malaria, schistosomiasis and leishmaniases are among the most prevalent tropical parasitic diseases and each requires new innovative treatments. Targeting essential parasite pathways, such as those that regulate gene expression and cell cycle progression, is a key strategy for discovering new drug leads. In this study, four clinically approved anti-cancer drugs (Vorinostat, Belinostat, Panobinostat and Romidepsin) that target histone/lysine deacetylase enzymes were examined for in vitro activity against Plasmodium knowlesi, Schistosoma mansoni, Leishmania amazonensis and L. donovani parasites and two for in vivo activity in a mouse malaria model. All four compounds were potent inhibitors of P. knowlesi malaria parasites (IC50 9-370 nM), with belinostat, panobinostat and vorinostat having 8-45 fold selectivity for the parasite over human neonatal foreskin fibroblast (NFF) or human embryonic kidney (HEK 293) cells, while romidepsin was not selective. Each of the HDAC inhibitor drugs caused hyperacetylation of P. knowlesi histone H4. None of the drugs was active against Leishmania amastigote or promastigote parasites (IC50 > 20 μM) or S. mansoni schistosomula (IC50 > 10 μM), however romidepsin inhibited S. mansoni adult worm parings and egg production (IC50 ∼10 μM). Modest in vivo activity was observed in P. berghei infected mice dosed orally with vorinostat or panobinostat (25 mg/kg twice daily for four days), with a significant reduction in parasitemia observed on days 4-7 and 4-10 after infection (P < 0.05), respectively.

  4. Septins of Platyhelminths: identification, phylogeny, expression and localization among developmental stages of Schistosoma mansoni.

    PubMed

    Zeraik, Ana E; Rinaldi, Gabriel; Mann, Victoria H; Popratiloff, Anastas; Araujo, Ana P U; Demarco, Ricardo; Brindley, Paul J

    2013-01-01

    Septins are a family of eukaryotic GTP binding proteins conserved from yeasts to humans. Originally identified in mutants of budding yeast, septins participate in diverse cellular functions including cytokinesis, organization of actin networks, cell polarity, vesicle trafficking and many others. Septins assemble into heteroligomers to form filaments and rings. Here, four septins of Schistosoma mansoni are described, which appear to be conserved within the phylum Platyhelminthes. These orthologues were related to the SEPT5, SEPT10 and SEPT7 septins of humans, and hence we have termed the schistosome septins SmSEPT5, SmSEPT10, SmSEPT7.1 and SmSEPT7.2. Septin transcripts were detected throughout the developmental cycle of the schistosome and a similar expression profile was observed for septins in the stages examined, consistent with concerted production of these proteins to form heterocomplexes. Immunolocalization analyses undertaken with antibodies specific for SmSEPT5 and SmSEPT10 revealed a broad tissue distribution of septins in the schistosomulum and colocalization of septin and actin in the longitudinal and circular muscles of the sporocyst. Ciliated epidermal plates of the miracidium were rich in septins. Expression levels for these septins were elevated in germ cells in the miracidium and sporocyst. Intriguingly, septins colocalize with the protonephridial system of the cercaria, which extends laterally along the length of this larval stage. Together, the findings revealed that schistosomes expressed several septins which likely form filaments within the cells, as in other eukaryotes. Identification and localization demonstrating a broad distribution of septins across organs and tissues of schistosome contributes towards the understanding of septins in schistosomes and other flatworms.

  5. Basophil depletion downregulates Schistosoma mansoni egg-induced granuloma formation.

    PubMed

    Anyan, William K; Seki, Takenori; Kumagai, Takashi; Obata-Ninomiya, Kazushige; Furushima-Shimogawara, Rieko; Kwansa-Bentum, Bethel; Akao, Nobuaki; Bosompem, Kwabena M; Boakye, Daniel A; Wilson, Michael D; Karasuyama, Hajime; Ohta, Nobuo

    2013-12-01

    Granuloma formation around parasite eggs during schistosomal infection is considered to be controlled by Th2 cytokines. However, it is still controversial which cell populations are responsible for the host Th2 cytokine-dependent granuloma formation. Basophils have recently attracted attention because of their ability to produce large amounts of IL-4. Therefore, we investigated whether basophils play an essential role in the induction of granuloma formation induced by Schistosoma mansoni eggs. Together with our previous observation that basophil numbers increased markedly in the spleen at 7 weeks postinfection, immunohistochemical staining using anti-mMCP8 monoclonal antibody (mAb) showed basophil infiltration in the granulomatous lesions formed around parasite eggs. To examine the roles of basophils more directly, we treated mice with anti-CD200R3 mAb to deplete basophils. Depletion of basophils resulted in a reduction of basophil number with concomitant downregulation of egg granuloma formation at 7 weeks postinfection. Moreover, we observed a significant reduction in the size of egg granulomas formed in basophil-depleted mice in the pulmonary granuloma model. Taken together, these findings indicated that basophils are essential for S. mansoni egg-induced granuloma formation, and this may serve as a novel therapeutic target in ameliorating the pathology of schistosomiasis.

  6. Structure and kinetics assays of recombinant Schistosoma mansoni dihydrofolate reductase.

    PubMed

    Serrão, Vitor Hugo Balasco; Romanello, Larissa; Cassago, Alexandre; de Souza, Juliana Roberta Torini; Cheleski, Juliana; DeMarco, Ricardo; Brandão-Neto, José; Pereira, Humberto D'Muniz

    2017-03-11

    The parasite Schistosoma mansoni possesses all pathways for pyrimidine biosynthesis, in which dihydrofolate reductase (DHFR), thymidylate cycle participants, is essential for nucleotide metabolism to obtain energy and structural nucleic acids. Thus, DHFRs have been widely suggested as therapeutic targets for the treatment of infectious diseases. In this study, we expressed recombinant SmDHFR in a heterologous manner to obtain structural, biochemical and kinetic information. X-ray diffraction of recombinant SmDHFR at 1.95Å resolution showed that the structure exhibited the canonical DHFR fold. Isothermal titration calorimetry was used to determine the kinetic constants for NADP(+) and dihydrofolate. Moreover, inhibition assays were performed using the commercial folate analogs methotrexate and aminopterin; these analogs are recognized as folate competitors and are used as chemotherapeutic agents in cancer and autoimmune diseases. This study provides information that may prove useful for the future discovery of novel drugs and for understanding these metabolic steps from this pathway of S. mansoni, thus aiding in our understanding of the function of these essential pathways for parasite metabolism.

  7. Mitochondrial dynamics in the mouse liver infected by Schistosoma mansoni.

    PubMed

    Chen, Tina Tu-Wen; Wu, Lawrence Shih Hsin; Hsu, Paul Wei-Che; Pang, Cheng-Yoong; Lee, Kin-Mu; Cheng, Po-Ching; Peng, Shih-Yi

    2015-08-01

    Mitochondrial dynamics is crucial for regulation of cell homeostasis. Schistosoma mansoni is one of the most common parasites known to cause liver disease. Mice infected by S. mansoni show acute symptoms of schistosomiasis after 8 weeks. Hence, in this study, we attempted to assess the direct effects of S. mansoni infection on mice liver, and to explore the expression of mitochondrial morphology, dynamics, and function. Our recent findings show that S. mansoni infection changes mitochondrial morphology and affects mitochondrial functions, which attenuates mitochondrial membrane potential and ATP generation. S. mansoni-infected mice increases mitochondrial numbers by upregulating of genes involved in mitochondrial biogenesis, including peroxisome proliferator-activated receptor c co-activator 1α (PGC1α) and mitochondrial transcription factor A (Tfam). This may promote mitochondria generation for accelerating the recovery of mitochondrial functions. Moreover, S. mansoni would disrupt mitochondrial dynamics including induced mitochondrial fission and promoted mitochondrial fragmentation in mice liver. More importantly, S. mansoni further stimulated upregulation both extrinsic and intrinsic apoptosis pathway in infected mice liver. The intrinsic pathway was triggered by cytochrome c release. Additionally, NFκB (nuclear factor-kappa B, p65) could play a protective role to inhibit apoptosis through reducing active caspase-3 expression. Therefore, our results confirmed the liver damage mechanism of experimental schistosomiasis in mice model.

  8. Evaluating the risk of Schistosoma mansoni transmission in mainland China.

    PubMed

    Qu, Guoli; Wang, Wei; Lu, Xiaomin; Dai, Jianrong; Li, Xiaoheng; Liang, Yousheng

    2016-12-01

    Biomphalaria straminea, an intermediate host of Schistosoma mansoni, is predominantly distributed in the South Americas and Caribbean; however, this snail, as an invasive species, was introduced to Shenzhen, southern China, in 1981, and recent epidemiologic surveys demonstrate that the distribution of B. straminea has expanded across the Zhujiang River Basin, South China. In the presence of continuous importation of S. mansoni-infected cases, there is a growing concern about the transmission of S. mansoni in China. To evaluate the risk of S. mansoni transmission in China, we tested the compatibility of B. straminea captured from the snail habitats in southern China with S. mansoni in laboratory. We detected no S. mansoni infections in B. straminea following exposure to the parasite larvae at snail/miracidium ratios of 1:5, 1:10, 1:20, 1:40, and 1:80, while 6.7 to 66.7 % infections occurred in the control Biomphalaria glabrata depending on the ratio. The results of the present study demonstrate that the invasive B. straminea snails seem to be incompatible with S. mansoni, suggesting a low risk of S. mansoni transmission in mainland China.

  9. CHARACTERIZATION OF THE METHIONINE SULFOXIDE REDUCTASES OF SCHISTOSOMA MANSONI

    PubMed Central

    Oke, Tolulope T.; Moskovitz, Jackob; Williams, David L.

    2013-01-01

    Schistosomiasis, also known as Bilharzia, is an infectious disease caused by several species of Schistosoma. Twenty million individuals suffer severe symptoms and 200,000 people die annually from the disease. The host responds to the presence of S. mansoni by producing reactive oxygen species that cause oxidative stress. We hypothesized that schistosomes produce antioxidants in response to oxidative stress. A known antioxidant protein is methionine sulfoxide reductase (Msr). Methionine residues can be oxidized to methionine sulfoxide in the presence of oxidizing agents, which is readily reversed by the action of the Msr system. Two S. mansoni MsrB genes (MsrB1 and MsrB2) were cloned and the recombinant proteins expressed in bacteria and purified. The S. mansoni MsrB proteins contained the common conserved catalytic and zinc coordinating cysteines. Analysis of the proteins showed that both proteins promote the reduction of both free methionine sulfoxide (Met[O]) and dabsyl-Met(O) to free methionine (Met) and dabsyl-Met, respectively, while exhibiting differences in their specific activities towards these substrates. Using real-time PCR, both proteins were found to be expressed in all stages of the parasite’s life cycle with the highest level of expression of both proteins in the egg stage. This is the first description of MsrB proteins from a parasite. PMID:19604033

  10. The genome of the blood fluke Schistosoma mansoni.

    PubMed

    Berriman, Matthew; Haas, Brian J; LoVerde, Philip T; Wilson, R Alan; Dillon, Gary P; Cerqueira, Gustavo C; Mashiyama, Susan T; Al-Lazikani, Bissan; Andrade, Luiza F; Ashton, Peter D; Aslett, Martin A; Bartholomeu, Daniella C; Blandin, Gaelle; Caffrey, Conor R; Coghlan, Avril; Coulson, Richard; Day, Tim A; Delcher, Art; DeMarco, Ricardo; Djikeng, Appolinaire; Eyre, Tina; Gamble, John A; Ghedin, Elodie; Gu, Yong; Hertz-Fowler, Christiane; Hirai, Hirohisha; Hirai, Yuriko; Houston, Robin; Ivens, Alasdair; Johnston, David A; Lacerda, Daniela; Macedo, Camila D; McVeigh, Paul; Ning, Zemin; Oliveira, Guilherme; Overington, John P; Parkhill, Julian; Pertea, Mihaela; Pierce, Raymond J; Protasio, Anna V; Quail, Michael A; Rajandream, Marie-Adèle; Rogers, Jane; Sajid, Mohammed; Salzberg, Steven L; Stanke, Mario; Tivey, Adrian R; White, Owen; Williams, David L; Wortman, Jennifer; Wu, Wenjie; Zamanian, Mostafa; Zerlotini, Adhemar; Fraser-Liggett, Claire M; Barrell, Barclay G; El-Sayed, Najib M

    2009-07-16

    Schistosoma mansoni is responsible for the neglected tropical disease schistosomiasis that affects 210 million people in 76 countries. Here we present analysis of the 363 megabase nuclear genome of the blood fluke. It encodes at least 11,809 genes, with an unusual intron size distribution, and new families of micro-exon genes that undergo frequent alternative splicing. As the first sequenced flatworm, and a representative of the Lophotrochozoa, it offers insights into early events in the evolution of the animals, including the development of a body pattern with bilateral symmetry, and the development of tissues into organs. Our analysis has been informed by the need to find new drug targets. The deficits in lipid metabolism that make schistosomes dependent on the host are revealed, and the identification of membrane receptors, ion channels and more than 300 proteases provide new insights into the biology of the life cycle and new targets. Bioinformatics approaches have identified metabolic chokepoints, and a chemogenomic screen has pinpointed schistosome proteins for which existing drugs may be active. The information generated provides an invaluable resource for the research community to develop much needed new control tools for the treatment and eradication of this important and neglected disease.

  11. Pedigree analysis of Czech Holstein calves with schistosoma reflexum

    PubMed Central

    2012-01-01

    Background Schistosoma reflexum (SR) is congenital syndrome briefly characterized by visceral eventration, severe dorsoflexion and ankylosis of the spine and arthrogryposis. A genetic etiology has been proposed, but conclusive evidence has not yet been provided. Methods Pedigree analysis was carried out in 29 cases of SR in Czech Holsteins and Holstein crosses. Genetic relationship was evaluated and inbreeding coefficients calculated. Pedigrees of 15 Czech Holsteins fathering non-SR affected calves were used for comparison. Results Twenty-one cases occurred in one pedigree founded by three sires while three SR calves occurred in another pedigree with a common grandfather. The sex ratio between affected males and females was 11:6. Affected calves shared common ancestors different from those shared by the unaffected calves. The inbreeding coefficient in the SR affected calves was not increased compared to unaffected calves. Conclusions The findings are consistent with SR being inherited autosomal recessively. Further studies are however needed to confirm this and therefore a breeding trial is recommended where a suspected heterozygous sire is mated to closely related females. PMID:22472123

  12. Characterization of a GABAergic neurotransmission in adult Schistosoma mansoni.

    PubMed

    Mendonça-Silva, D L; Gardino, P F; Kubrusly, R C C; De Mello, F G; Noël, F

    2004-08-01

    The neuromuscular systems of parasitic helminths are targets that are particularly amenable for anthelmintics. In this study, we describe a GABAergic neurotransmission in adult Schistosoma mansoni, the trematode responsible for high levels of morbidity in people living in developing countries. GABA immunoreactivity (GABA-IR) was detected in nerve cells and fibres of the cerebral ganglia and longitudinal nerve cords and the nerve plexuses ramifying throughout the parenchyma of male adult worms. In addition, strong GABA-IR was also found associated with the oral and ventral suckers as well as in testes indicating a role for GABA in fixation to the host vascular wall and spermatogenesis. The capacity to synthesize GABA from glutamate was confirmed by measurement of a glutamate decarboxylase (GAD) activity. Supporting these data, a single band with an apparent molecular weight of about 67 kDa was detected using an antibody raised against mammalian GAD. In vivo studies revealed that picrotoxin, a non-competitive antagonist of the GABAA receptor, produced a modification of the motility and locomotory behaviour of adult worms, suggesting that GABAergic signalling pathway may play a physiological role in the motonervous system of S. mansoni and could be considered as a potential target for the development of new drugs.

  13. Evaluation of "Myrrh extract" against Schistosoma mansoni: a histological study.

    PubMed

    Massoud, Ahmed M A; El Ebiary, Faika H; Ibrahim, Suzi H; Saleh, Hanan A A; Khalil, Hazem H M

    2010-04-01

    This study investigated the effect of myrrh extract on different developmental stages of Schistosoma mansoni. Sixty albino mice were used and divided into three main groups: GI (control group), GII (infected group) and GIII (infected-treated group). The last group was further divided into 3 subgroups where the drug was administered in a dose of 500 mg/kg body weight for 5 days starting on the 1st day PI for IIIA, on the 21st day PI for IIIB and on the 45th day PI for IIIC. A morphometric study was performed for the mean number and perimeter of granulomas. In GII, typical bilharzial granulomas were frequently encountered in the portal tracts with numerous eosinophils, collagen fiber deposition and reticular fiber condensation. Hepatocytes revealed vacuolation, nuclear affection and depletion of glycogen. In GIII, granulomas were less frequently observed with apparent decrease of eosinophils. The maximum effect of the drug was observed in SGs IIIB and IIIC as detected by significant decrease in the mean number and size of granulomas, paucity of eosinophils, decreased fibrosis and reticular fibers and the restoration of the glycogen content in the hepatocytes. The present data proved that myrrh has a valuable schistosomicidal effect against different stages of S. mansoni. This chemotherapeutic effect was more evident when the drug was given to infected mice on the 21st as well as on the 45th day PI.

  14. Schistosoma mansoni: neurotransmitters and the mobility of cercariae and schistosomules.

    PubMed

    Ercoli, N; Payares, G; Nuñez, D

    1985-04-01

    The concentration-dependent action of alkyl-isothiouroniums on Schistosoma mansoni cercariae, ranging from partial to total abolition of locomotor and flame cell movements, and/or suppression of virulence, is due to H1-histamine receptor inhibition. Correspondingly, H1-receptor inhibitors of widely different chemical structure, such as clemizol, diphenhydramine, brompheniramine, and promethazine, in 0.03-0.06 nM concentrations, induced an analogous cercarial immobilization reversed by addition of excess histamine. In contrast, the H2-receptor inhibitors cimetidine and metiamide did not immobilize cercariae. Histamine, acetylcholine, and serotonin, added to cercarial suspensions, showed no direct activity. Their participation in the mechanism of cercarial mobility was shown by the dose-dependent effects of antagonists, such as the serotonin antagonist methysergide and the acetylcholinesterase inhibitor physostigmine. These effects were not reversible by addition of serotonin and acetylcholine, respectively. A histamine-irreversible cercarial immobilization induced by the H-liberator 48/80 suggested that, besides H1-receptor inhibition, H-liberation and/or depletion also participated in mobility and survival. The detection of histamine in the cercaria corroborated the participation of histaminergic mechanisms. S. mansoni schistosomules collected from the mouse lung reacted to H1 antihistamines like cercariae, with a dose-dependent reduction of mobility and somatic deformation, such as vacuolization, granulation, and caecal enlargement.

  15. Ultra-low-cost urine filtration for Schistosoma haematobium diagnosis: a proof-of-concept study.

    PubMed

    Ephraim, Richard K D; Duah, Evans; Andrews, Jason R; Bogoch, Isaac I

    2014-09-01

    Simple, efficient, and cost-effective strategies are needed for urine sample preparation in the field diagnosis of infection with Schistosoma haematobium. In this proof-of-concept study, we evaluated inexpensive and widely available paper products (paper towels, school workbook paper, and newspaper) to gravity-filter urine containing 60 eggs/mL of Schistosoma haematobium. Eggs were reliably visualized by light microscopy by using single-ply paper towels as urine filters. This filtration method has broad applicability in clinical and public health settings in resource-constrained environments.

  16. The susceptibility of rodents to schistosome infection, with special reference to Schistosoma haematobium.

    PubMed

    Gear, J H; Davis, D H; Pitchford, R J

    1966-01-01

    In this investigation the susceptibility of several species of rodents-Praomys (Mastomys) natalensis, Saccostomus campestris, Arvicanthus niloticus, Aethomys chrysophilus, Tatera brantsi and the white mouse (SAIMR 200 strain)-to Schistosoma haematobium was determined and the pathology studied. From the results it is clear that these rodents are susceptible to infection with Schistosoma haematobium. For various reasons, notably adaptability to laboratory conditions, the most suitable as laboratory animals for the study of bilharziasis are Saccostomus campestris, Arvicanthus niloticus and Praomys (Mastomys) natalensis. These three species breed readily in the laboratory and show a high susceptibility to S. haematobium, with characteristic lesions involving several organs, including the lungs, liver, spleen, pancreas and intestine.

  17. Magnetic Resonance Spectroscopy for Evaluating Portal-Systemic Encephalopathy in Patients with Chronic Hepatic Schistosomiasis Japonicum

    PubMed Central

    Li, Ying; Mei, Lihong; Qiang, Jinwei; Ju, Shuai; Zhao, Shuhui

    2016-01-01

    Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients. PMID:27977668

  18. Expression of Bradyrhizobium japonicum cbb(3) terminal oxidase under denitrifying conditions is subjected to redox control.

    PubMed

    Bueno, Emilio; Richardson, David J; Bedmar, Eulogio J; Delgado, María J

    2009-09-01

    Bradyrhizobium japonicum utilizes cytochrome cbb(3) oxidase encoded by the fixNOQP operon to support microaerobic respiration under free-living and symbiotic conditions. It has been previously shown that, under denitrifying conditions, inactivation of the cycA gene encoding cytochrome c(550), the electron donor to the Cu-containing nitrite reductase, reduces cbb(3) expression. In order to establish the role of c(550) in electron transport to the cbb(3) oxidase, in this work, we have analyzed cbb(3) expression and activity in the cycA mutant grown under microaerobic or denitrifying conditions. Under denitrifying conditions, mutation of cycA had a negative effect on cytochrome c oxidase activity, heme c (FixP and FixO) and heme b cytochromes as well as expression of a fixP'-'lacZ fusion. Similarly, cbb(3) oxidase was expressed very weakly in a napC mutant lacking the c-type cytochrome, which transfers electrons to the NapAB structural subunit of the periplasmic nitrate reductase. These results suggest that a change in the electron flow through the denitrification pathway may affect the cellular redox state, leading to alterations in cbb(3) expression. In fact, levels of fixP'-'lacZ expression were largely dependent on the oxidized or reduced nature of the carbon source in the medium. Maximal expression observed in cells grown under denitrifying conditions with an oxidized carbon source required the regulatory protein RegR.

  19. Population Densities of Rhizobium japonicum Strain 123 Estimated Directly in Soil and Rhizospheres †

    PubMed Central

    Reyes, V. G.; Schmidt, E. L.

    1979-01-01

    Rhizobium japonicum serotype 123 was enumerated in soil and rhizospheres by fluorescent antibody techniques. Counting efficiency was estimated to be about 30%. Indigenous populations of strain 123 ranged from a few hundred to a few thousand per gram of field soil before planting. Rhizosphere effects from field-grown soybean plants were modest, reaching a maximum of about 2 × 104 cells of strain 123 per g of inner rhizosphere soil in young (16-day-old) plants. Comparably slight rhizosphere stimulation was observed with field corn. High populations of strain 123 (2 × 106 to 3 × 106 cells per g) were found only in the disintegrating taproot rhizospheres of mature soybeans at harvest, and these populations declined rapidly after harvest. Pot experiments with the same soil provided data similar to those derived from the field experiments. Populations of strain 123 reached a maximum of about 105 cells per g of soybean rhizosphere soil, but most values were lower and were only slightly higher than values in wheat rhizosphere soil. Nitrogen treatments had little effect on strain 123 densities in legume and nonlegume rhizospheres or on the nodulation success of strain 123. No evidence was obtained for the widely accepted theory of specific stimulation, which has been proposed to account for the initiation of the Rhizobium-legume symbiosis. PMID:16345383

  20. DNA Microarray-Based Identification of Genes Regulated by NtrC in Bradyrhizobium japonicum

    PubMed Central

    Franck, William L.; Qiu, Jing; Lee, Hae-In; Stacey, Gary

    2015-01-01

    The Bradyrhizobium japonicum NtrBC two-component system is a critical regulator of cellular nitrogen metabolism, including the acquisition and catabolism of nitrogenous compounds. To better define the roles of this system, genome-wide transcriptional profiling was performed to identify the NtrC regulon during the response to nitrogen limitation. Upon cells perceiving low intracellular nitrogen, they stimulate the phosphorylation of NtrC, which induces genes responsible for alteration of the core glutamine synthetase/glutamate synthase nitrogen assimilation pathway, including the genes for the glutamine synthetases and PII proteins. In addition, genes responsible for the import and utilization of multiple nitrogen sources, specifically nitrate and nitrite, were upregulated by NtrC activation. Mutational analysis of a candidate nitrite reductase revealed a role for NtrC in regulating the assimilation of nitrite, since mutations in both ntrC and the gene encoding the candidate nitrite reductase abolished the ability to grow on nitrite as a sole nitrogen source. PMID:26025905

  1. Identification and characterization of a novel Bradyrhizobium japonicum gene involved in host-specific nitrogen fixation.

    PubMed Central

    Chun, J Y; Sexton, G L; Roth, L E; Stacey, G

    1994-01-01

    To understand the genetic mechanism of host specificity in the interaction between rhizobia and their hosts, it is important to identify genes that influence both early and late steps in symbiotic development. This paper focuses on the little-understood genetics of host-specific nitrogen fixation. A deletion mutant of Bradyrhizobium japonicum, strain NAD163, was found to induce effective, nitrogen-fixing nodules on soybean and siratro plants but produced ineffective nodules on cowpea plants. Additional transposon and deletion mutants defined a small region that conferred this phenotype, and this region was sequenced to identify two putative open reading frames (ORFs). Data indicate that only one of these ORFs is detectable in bacteroids. This ORF was termed hsfA, with a predicted protein product of 11 kDa. The transcriptional start site of hsfA was determined and found to coincide with a predicted RpoN-dependent promoter. Microscopic studies of nodules induced by the wild type and hsfA mutants on cowpea and soybean plants indicate that the cowpea mutant nodules are slow to develop. The data indicate that hsfA appears to play a crucial role in bacteroid development on cowpea but does not appear to be essential for nitrogen fixation on the other hosts tested. Images PMID:7961425

  2. Peucedanum japonicum Thunb inhibits high-fat diet induced obesity in mice.

    PubMed

    Okabe, Takafumi; Toda, Takayoshi; Nukitrangsan, Natthanan; Inafuku, Masashi; Iwasaki, Hironori; Oku, Hirosuke

    2011-06-01

    This study examined the antiobese activity of Peucedanum japonicum Thunb (PJT) in mice. In the first experiment, 4-week-old C57BL/6 mice were fed seven different diets containing 15% corn oil and 0-20% PJT powder for 4 weeks. Feeding the 10% and 20% PJT diet suppressed the body weight gain and the accumulation of abdominal and subcutaneous fats. PJT reduced serum and liver levels of triglyceride and serum levels of leptin in a dose-dependent manner. PJT intake decreased the proportion of saturated fatty acids and increased polyunsaturated and n-3 fatty acids in the liver. To obtain more insight into the antiobese activity of PJT, its effect on lipid absorption and enzyme activities related to lipid metabolism was studied in the second experiment. There was an increased faecal excretion of triglyceride in mice fed 5% and 10% PJT diets. Fatty acid synthase activity was decreased while carnitine palmitoyltransferase activity was increased by 10% PJT intake. These findings pointed to the usefulness of PJT for the development of a safe natural agent to reduce obesity or body weight for the first time. The rationale for the lipid lowering mechanism of PJT and the candidate compound responsible for the observations have also been discussed.

  3. Constituents of the leaves of Peucedanum japonicum Thunb. and their biological activity.

    PubMed

    Hisamoto, Masashi; Kikuzaki, Hiroe; Nakatani, Nobuji

    2004-02-11

    In the course of our study on the isolation and structure determination of constituents in tropical plants, we focused on Peucedanum japonicum Thunb., belonging to the family Umbelliferae. In this study, a new C(13) norisoprenoid glucoside, (3S)-O-beta-d-glucopyranosyl-6-[3-oxo-(2S)-butenylidenyl]-1,1,5-trimethylcyclohexan-(5R)-ol (1), and two new phenylpropanoid glucosides, 3-(2-O-beta-d-glucopyranosyl-4-hydroxyphenyl)propanoic acid (3) and methyl 3-(2-O-beta-d-glucopyranosyl-4-hydroxyphenyl)propanoate (4), were isolated from the n-butanol soluble fraction of this plant's leaves, together with five known compounds. The structures of these compounds were determined on the basis of spectroscopic evidence. In addition, all isolated compounds were examined for scavenging activity against 1,1-diphenyl-2-picrylhydrazyl radical and inhibitory activity against mushroom tyrosinase. These results suggested that 2-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol (7) and 3-O-beta-d-glucopyranosyl-2-(4-hydroxy-3-methoxyphenyl)propanol (8) showed an appreciable activity in both assay systems.

  4. Effect of phosducin silencing on the photokinetic motile response of Blepharisma japonicum.

    PubMed

    Sobierajska, Katarzyna; Joachimiak, Ewa; Bregier, Cezary; Fabczak, Stanisław; Fabczak, Hanna

    2011-01-01

    The coloured ciliate Blepharisma japonicum changes swimming velocity (positive photokinesis) and elongates its body in response to a prolonged illumination. We have recently proposed that alterations in the phosphorylation level of the ciliate phosducin (Pdc) may be involved in light-induced cell elongation, which in turn affects the interaction of βγ-dimer of G-proteins (Gβγ) with β-tubulin and subsequent cytoskeletal remodelling. The cellular mechanism that governs the photokinetic effect in this ciliate has not been elucidated. In the present study, we utilise real-time PCR to demonstrate that the levels of ciliate Pdc mRNA are significantly reduced in Pdc-RNAi-treated cells compared to cells fed with bacteria carrying the empty vector (control cells). Using western immunoblotting, we confirmed that these cells treated with Pdc-RNAi expressed a substantially lower level of the Pdc protein. The assay also revealed that in ciliates treated with Pdc-RNAi and exposed to light, the cytosolic level of Gβ (~36 kDa) was reduced, whereas the level of Gβ localized to the membrane (~32 kDa) was increased compared to control cells. In addition, behavioural analysis of the cells indicated a substantial reduction of photokinesis. The findings in this study provide additional characterization of the functional properties of the ciliate Pdc protein and we discuss a likely role for this phosphoprotein in the photokinetic phenomenon of the ciliate protist Blepharisma.

  5. Stable aquaculture of the Japanese lancelet Branchiostoma japonicum for 7 years.

    PubMed

    Yasui, Kinya; Igawa, Takeshi; Kaji, Takao; Henmi, Yasuhisa

    2013-12-01

    Despite advances in the study on animal evolution in the last two decades, paucity of experimental data on cephalochordates comparable to those on the other chordates hinders an integrative understanding of chordate evolutionary history. To obtain lancelet data under well-controlled experiments, laboratory cultures of lancelets have been performed at several institutions. In a mass culture started in 2005, we have obtained up to three consecutive generations of Branchiostoma japonicum. Using sand substratum, survival rates of laboratory lancelets until maturation have improved to greater than 30%, much higher than compared to previously, and for adults the annual average survival rate was 82.3%. The high survival rate allows maintaining animals at least 6 years and potentially longer. Water temperatures lower than 23°C obviously reduced the frequency of spawning even after the onset of spawning period, and 1-2 days after changing the temperature at 25°C animals became spawned well. We also observed obvious sex reversal from male to female in individuals that had been cultured for 3 years or more. Our continuous culture has provided sufficient materials for vital experiments on early development and for studying metamorphosis, as well as for the conservation of wild populations. The subculture of successive laboratory generations will provide a valuable resource for genetic studies.

  6. Identification of a novel antimicrobial peptide from amphioxus Branchiostoma japonicum by in silico and functional analyses.

    PubMed

    Liu, Haohan; Lei, Miaomiao; Du, Xiaoyuan; Cui, Pengfei; Zhang, Shicui

    2015-12-18

    The emergence of multi-drug resistant (MDR) microbes leads to urgent demands for novel antibiotics exploration. We demonstrated a cDNA from amphioxus Branchiostoma japonicum, designated Bjamp1, encoded a protein with features typical of antimicrobial peptides (AMPs), which is not homologous to any AMPs currently discovered. It was found that Bjamp1 was expressed in distinct tissues, and its expression was remarkably up-regulated following challenge with LPS and LTA. Moreover, the synthesized putative mature AMP, mBjAMP1, underwent a coil-to-helix transition in the presence of TFE or SDS, agreeing well with the expectation that BjAMP1 was a potential AMP. Functional assays showed that mBjAMP1 inhibited the growth of all the bacteria tested, and induced membrane/cytoplasmic damage. ELISA indicated that mBjAMP1 was a pattern recognition molecule capable of identifying LPS and LTA. Importantly, mBjAMP1 disrupted the bacterial membranes by a membranolytic mechanism. Additionally, mBjAMP1 was non-cytotoxic to mammalian cells. Collectively, these data indicate that mBjAMP1 is a new AMP with a high bacterial membrane selectivity, rendering it a promising template for the design of novel peptide antibiotics against MDR microbes. It also shows for the first time that use of signal conserved sequence of AMPs is effective identifying potential AMPs across different animal classes.

  7. Development of oral and branchial muscles in lancelet larvae of Branchiostoma japonicum.

    PubMed

    Yasui, Kinya; Kaji, Takao; Morov, Arseniy R; Yonemura, Shigenobu

    2014-04-01

    The perforated pharynx has generally been regarded as a shared characteristic of chordates. However, there still remains phylogenetic ambiguity between the cilia-driven system in invertebrate chordates and the muscle-driven system in vertebrates. Giant larvae of the genus Asymmetron were reported to develop an orobranchial musculature similar to that of vertebrates more than 100 years ago. This discovery might represent an evolutionary link for the chordate branchial system, but few investigations of the lancelet orobranchial musculature have been completed since. We studied staged larvae of a Japanese population of Branchiostoma japonicum to characterize the developmental property of the orobranchial musculature. The larval mouth and the unpaired primary gills develop well-organized muscles. These muscles function only as obturators of the openings without antagonistic system. As the larval mouth enlarged posteriorly to the level of the ninth myomere, the oral musculature was fortified accordingly without segmental patterning. In contrast, the iterated branchial muscles coincided with the dorsal myomeric pattern before metamorphosis, but the pharynx was remodeled dynamically irrespective of the myomeric pattern during metamorphosis. The orobranchial musculature disappeared completely during metamorphosis, and adult muscles in the oral hood and velum, as well as on the pterygial coeloms developed independently. The lancelet orobranchial musculature is apparently a larval adaptation to prevent harmful intake. However, vestigial muscles appeared transiently with the secondary gill formation suggest a bilateral ancestral state of muscular gills, and a segmental pattern of developing branchial muscles without neural crest and placodal contributions is suggestive of a precursor of vertebrate branchiomeric pattern.

  8. Identification and expression of an encoding steroid receptor coactivator (SRA) in amphioxus (Branchiostoma japonicum).

    PubMed

    Sun, Huanhuan; Gao, Lili; Pang, Qiuxiang; Sun, Lele; Wu, Di; Bai, Yun; Zhao, Bosheng; Dong, Juan

    2013-11-01

    Steroid receptor coactivator (SRA), a class of genes encoding both functional RNA and protein, has been shown to be present in vertebrates but little is known in invertebrates. Here we isolated a cDNA encoding a SRA homolog from amphioxus Branchiostoma japonicum, named AmphiSRA. The cDNA contained a 525 bp open reading frame corresponding to a deduced protein of 174 amino acids with a predicted molecular mass of ~21 kDa. Phylogenetic analysis showed that AmphiSRA was located at the base of its vertebrate counterparts, suggesting that it represents the archetype of vertebrate SRA. The genomic DNA sequence of AmphiSRA contained four exons and three introns, which was similar to B. floridae SRA exon/intron organization. The recombinant SRAP expressed in vitro shows a band with a molecular mass of 21 kDa and western blot confirmed it, which proved it is an encoding isoform. AmphiSRA is found to display a tissue specific expression pattern, with a predominant expression in gill, intestine, testis, neural tube and notochord. The whole-mount in situ hybridization demonstrated the expression of AmphiSRA in all the stages of development assayed. These implicated that SRA maybe play an important role during embryonic development of cephalochordate amphioxus.

  9. Rapid synthesis and metabolism of glutamate in N/sub 2/-fixing bacteroids. [Bradyrhizobium japonicum

    SciTech Connect

    Salminen, S.O.; Streeter, J.G.

    1987-04-01

    Symbiotic nodule bacteroids are thought to support N/sub 2/ fixation mainly by metabolizing dicarboxylic acids to CO/sub 2/, generating reductant and ATP required by nitrogenase. Bradyrhizobium japonicum bacteroids were isolated anaerobically and incubated at 2% O/sub 2/ with /sup 14/C-labeled succinate, malate, glutamate, or aspartate. /sup 14/CO/sub 2/ was collected, and the bacteroid contents separated into neutral, organic acid, and amino acid fractions. The respiration of substrates, relative to their uptake, was malate > glutamate > succinate > aspartate. Analysis of the fractions revealed that will all substrates the radioactivity was found mostly in the amino acid fraction. The labeling of the neutral fraction was negligible and only a small amount of label was found in the organic acid fraction indicating a small pool size. TLC of the amino acid fraction showed the label to be principally in glutamate. Glutamate contained 67, 80, 97, and 88% of the /sup 14/C in the amino acid fraction in bacteroids fed with succinate, malate, glutamate and aspartate, respectively. The data suggest that glutamate may play an important role in the bacteroid function.

  10. Identification of a novel antimicrobial peptide from amphioxus Branchiostoma japonicum by in silico and functional analyses

    PubMed Central

    Liu, Haohan; Lei, Miaomiao; Du, Xiaoyuan; Cui, Pengfei; Zhang, Shicui

    2015-01-01

    The emergence of multi-drug resistant (MDR) microbes leads to urgent demands for novel antibiotics exploration. We demonstrated a cDNA from amphioxus Branchiostoma japonicum, designated Bjamp1, encoded a protein with features typical of antimicrobial peptides (AMPs), which is not homologous to any AMPs currently discovered. It was found that Bjamp1 was expressed in distinct tissues, and its expression was remarkably up-regulated following challenge with LPS and LTA. Moreover, the synthesized putative mature AMP, mBjAMP1, underwent a coil-to-helix transition in the presence of TFE or SDS, agreeing well with the expectation that BjAMP1 was a potential AMP. Functional assays showed that mBjAMP1 inhibited the growth of all the bacteria tested, and induced membrane/cytoplasmic damage. ELISA indicated that mBjAMP1 was a pattern recognition molecule capable of identifying LPS and LTA. Importantly, mBjAMP1 disrupted the bacterial membranes by a membranolytic mechanism. Additionally, mBjAMP1 was non-cytotoxic to mammalian cells. Collectively, these data indicate that mBjAMP1 is a new AMP with a high bacterial membrane selectivity, rendering it a promising template for the design of novel peptide antibiotics against MDR microbes. It also shows for the first time that use of signal conserved sequence of AMPs is effective identifying potential AMPs across different animal classes. PMID:26680226

  11. Characterization of a cellular retinol-binding protein from lamprey, Lethenteron japonicum.

    PubMed

    Mezaki, Yoshihiro; Morii, Mayako; Yoshikawa, Kiwamu; Yamaguchi, Noriko; Miura, Mitsutaka; Imai, Katsuyuki; Yoshino, Hiroaki; Senoo, Haruki

    2012-03-01

    Lampreys are ancestral representatives of vertebrates known as jawless fish. The Japanese lamprey, Lethenteron japonicum, is a parasitic member of the lampreys known to store large amounts of vitamin A within its body. How this storage is achieved, however, is wholly unknown. Within the body, the absorption, transfer and metabolism of vitamin A are regulated by a family of proteins called retinoid-binding proteins. Here we have cloned a cDNA for cellular retinol-binding protein (CRBP) from the Japanese lamprey, and phylogenetic analysis suggests that lamprey CRBP is an ancestor of both CRBP I and II. The lamprey CRBP protein was expressed in bacteria and purified. Binding of the lamprey CRBP to retinol (Kd of 13.2 nM) was identified by fluorimetric titration. However, results obtained with the protein fluorescence quenching technique indicated that lamprey CRBP does not bind to retinal. Northern blot analysis showed that lamprey CRBP mRNA was ubiquitously expressed, although expression was most abundant in the intestine. Together, these results suggest that lamprey CRBP has an important role in absorbing vitamin A from the blood of host animals.

  12. Magnetic Resonance Spectroscopy for Evaluating Portal-Systemic Encephalopathy in Patients with Chronic Hepatic Schistosomiasis Japonicum.

    PubMed

    Li, Ying; Mei, Lihong; Qiang, Jinwei; Ju, Shuai; Zhao, Shuhui

    2016-12-01

    Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients.

  13. Conservation genetics of an endangered lady's slipper orchid: Cypripedium japonicum in China.

    PubMed

    Qian, Xin; Li, Quan-Jian; Liu, Fen; Gong, Mao-Jiang; Wang, Cai-Xia; Tian, Min

    2014-06-30

    Knowledge about the population genetic variation of the endangered orchid, Cypripedium japonicum, is conducive to the development of conservation strategies. Here, we examined the levels and partitioning of inter-simple sequence repeat (ISSR) diversity (109 loci) in five populations of this orchid to gain insight into its genetic variation and population structure in Eastern and Central China. It harbored considerably lower levels of genetic diversity both at the population (percentage of polymorphic loci (PPL) = 11.19%, Nei's gene diversity (H) = 0.0416 and Shannon's information index (I) = 0.0613) and species level (PPL = 38.53%, H = 0.1273 and I = 0.1928) and a significantly higher degree of differentiation among populations (the proportion of the total variance among populations (Φpt) = 0.698) than those typical of ISSR-based studies in other orchid species. Furthermore, the Nei's genetic distances between populations were independent of the corresponding geographical distances. Two main clusters are shown in an arithmetic average (UPGMA) dendrogram, which is in agreement with the results of principal coordinate analysis (PCoA) analysis and the STRUCTURE program. In addition, individuals within a population were more similar to each other than to those in other populations. Based on the genetic data and our field survey, the development of conservation management for this threatened orchid should include habitat protection, artificial gene flow and ex situ measures.

  14. Conservation Genetics of an Endangered Lady’s Slipper Orchid: Cypripedium japonicum in China

    PubMed Central

    Qian, Xin; Li, Quan-Jian; Liu, Fen; Gong, Mao-Jiang; Wang, Cai-Xia; Tian, Min

    2014-01-01

    Knowledge about the population genetic variation of the endangered orchid, Cypripedium japonicum, is conducive to the development of conservation strategies. Here, we examined the levels and partitioning of inter-simple sequence repeat (ISSR) diversity (109 loci) in five populations of this orchid to gain insight into its genetic variation and population structure in Eastern and Central China. It harbored considerably lower levels of genetic diversity both at the population (percentage of polymorphic loci (PPL) = 11.19%, Nei’s gene diversity (H) = 0.0416 and Shannon’s information index (I) = 0.0613) and species level (PPL = 38.53%, H = 0.1273 and I = 0.1928) and a significantly higher degree of differentiation among populations (the proportion of the total variance among populations (Φpt) = 0.698) than those typical of ISSR-based studies in other orchid species. Furthermore, the Nei’s genetic distances between populations were independent of the corresponding geographical distances. Two main clusters are shown in an arithmetic average (UPGMA) dendrogram, which is in agreement with the results of principal coordinate analysis (PCoA) analysis and the STRUCTURE program. In addition, individuals within a population were more similar to each other than to those in other populations. Based on the genetic data and our field survey, the development of conservation management for this threatened orchid should include habitat protection, artificial gene flow and ex situ measures. PMID:24983476

  15. Rhizobium japonicum mutant strains unable to grow chemoautotrophically with H2.

    PubMed Central

    Maier, R J

    1981-01-01

    Rhizobium japonicum strain SR grows chemoautotrophically on a mineral salts medium when incubated in an H2- and CO2-containing atmosphere. Mutant strains unable to grow or that grow very poorly chemoautotrophically with H2 have been isolated from strain SR. The mutant isolation procedure involved mutagenesis with ethyl methane sulfonate, penicillin selection under chemoautotrophic growth conditions, and plating of the survivors onto medium containing carbon. The resulting colonies were replica plated onto medium that did not contain carbon, and the plates were incubated in an H2- and CO2-containing atmosphere. Mutant strains unable to grow under these conditions were chosen. Over 100 mutant strains with defects in chemoautotrophic metabolism were obtained. The phenotypes of the mutants fall into various classes. These include strains unable to oxidize H2 and strains deficient in CO2 uptake. Some of the mutant strains were capable of oxidizing H2 only when artificial electron acceptors were provided. Two mutant strains specifically lack activity of the key CO2-fixing enzyme ribulose 1,5-bisphosphate carboxylase. Other mutant strains lack both H2-oxidizing ability and ribulose 1,5-bisphosphate carboxylase activity. PMID:6780521

  16. Rhodococcus cercidiphylli sp. nov., a new endophytic actinobacterium isolated from a Cercidiphyllum japonicum leaf.

    PubMed

    Li, Jie; Zhao, Guo-Zhen; Chen, Hua-Hong; Qin, Sheng; Xu, Li-Hua; Jiang, Cheng-Lin; Li, Wen-Jun

    2008-06-01

    An endophytic actinobacterium, designated YIM 65003(T), was isolated from a surface sterilized leaf sample of Cercidiphyllum japonicum collected from Yunnan province, south-west China. The morphological and chemotaxonomic properties of the isolate were typical of members of the genus Rhodococcus. Analysis of the 16S rRNA gene sequence revealed that the isolate was most closely related to Rhodococcus fascians DSM 20669(T) (99.6%) and Rhodococcus yunnanensis YIM 70056(T) (99.0%). DNA-DNA hybridization with the above microorganisms (46.3% and 48.8%, respectively), in combination with differences in the biochemical and physiological properties, suggested that strain YIM 65003(T) should be classified within a novel species of the genus Rhodococcus, for which the name Rhodococcus cercidiphylli sp. nov. is proposed, with YIM 65003(T) (=CCTCC AB 207160(T)=DSM 45141(T)) as the type strain. The 16S rRNA gene sequence of strain YIM 65003(T) has been deposited in GenBank under the accession number EU325542.

  17. A rhodopsin immunoanalog in the related photosensitive protozoans Blepharisma japonicum and Stentor coeruleus.

    PubMed

    Fabczak, Hanna; Sobierajska, Katarzyna; Fabczak, Stanisław

    2008-09-01

    Immunoblotting of isolated cell membrane fractions from ciliates Blepharisma japonicum and Stentor coeruleus with a polyclonal antibody raised against rhodopsin revealed one strong protein band of about 36 kDa, thought to correspond to protozoan rhodopsin. Inspection of both ciliates labeled with the same antibody using a confocal microscope confirmed the immunoblotting result and demonstrated the presence of these rhodopsin-like molecules localized within the cell membrane area. Immunoblot analysis of the ciliate membrane fractions resolved by two-dimensional gel electrophoresis identified two distinct 36 kDa spots at pIs of 4.5 and 7.0 for Blepharisma, and three spots at pIs of 4.4, 5.0 and 6.0 for Stentor, indicating a possible mixture of phosphorylated rhodopsin species in these cells. The obtained results suggest that both Blepharisma and the related ciliate Stentor contain within the cell membrane the rhodopsin-like proteins, which may be involved as receptor molecules in the sensory transduction pathway mediating motile photoresponses in these protists as in other species of lower eukaryota.

  18. DNA Microarray-Based Identification of Genes Regulated by NtrC in Bradyrhizobium japonicum.

    PubMed

    Franck, William L; Qiu, Jing; Lee, Hae-In; Chang, Woo-Suk; Stacey, Gary

    2015-08-15

    The Bradyrhizobium japonicum NtrBC two-component system is a critical regulator of cellular nitrogen metabolism, including the acquisition and catabolism of nitrogenous compounds. To better define the roles of this system, genome-wide transcriptional profiling was performed to identify the NtrC regulon during the response to nitrogen limitation. Upon cells perceiving low intracellular nitrogen, they stimulate the phosphorylation of NtrC, which induces genes responsible for alteration of the core glutamine synthetase/glutamate synthase nitrogen assimilation pathway, including the genes for the glutamine synthetases and PII proteins. In addition, genes responsible for the import and utilization of multiple nitrogen sources, specifically nitrate and nitrite, were upregulated by NtrC activation. Mutational analysis of a candidate nitrite reductase revealed a role for NtrC in regulating the assimilation of nitrite, since mutations in both ntrC and the gene encoding the candidate nitrite reductase abolished the ability to grow on nitrite as a sole nitrogen source.

  19. Structure, function and inhibition of ent-kaurene synthase from Bradyrhizobium japonicum.

    PubMed

    Liu, Wenting; Feng, Xinxin; Zheng, Yingying; Huang, Chun-Hsiang; Nakano, Chiaki; Hoshino, Tsutomu; Bogue, Shannon; Ko, Tzu-Ping; Chen, Chun-Chi; Cui, Yunfeng; Li, Jian; Wang, Iren; Hsu, Shang-Te Danny; Oldfield, Eric; Guo, Rey-Ting

    2014-10-01

    We report the first X-ray crystal structure of ent-kaur-16-ene synthase from Bradyrhizobium japonicum, together with the results of a site-directed mutagenesis investigation into catalytic activity. The structure is very similar to that of the α domains of modern plant terpene cyclases, a result that is of interest since it has been proposed that many plant terpene cyclases may have arisen from bacterial diterpene cyclases. The ent-copalyl diphosphate substrate binds to a hydrophobic pocket near a cluster of Asp and Arg residues that are essential for catalysis, with the carbocations formed on ionization being protected by Leu, Tyr and Phe residues. A bisphosphonate inhibitor binds to the same site. In the kaurene synthase from the moss Physcomitrella patens, 16-α-hydroxy-ent-kaurane as well as kaurene are produced since Leu and Tyr in the P. patens kaurene synthase active site are replaced by smaller residues enabling carbocation quenching by water. Overall, the results represent the first structure determination of a bacterial diterpene cyclase, providing insights into catalytic activity, as well as structural comparisons with diverse terpene synthases and cyclases which clearly separate the terpene cyclases from other terpene synthases having highly α-helical structures.

  20. A single-strand conformation polymorphism (SSCP) approach for investigating genetic interactions of Schistosoma haematobium and Schistosoma guineensis in Loum, Cameroon.

    PubMed

    Webster, B L; Tchuem Tchuenté, L A; Southgate, V R

    2007-03-01

    Single-strand conformation polymorphism (SSCP) analysis of the second internal transcribed spacer (ITS2) of nuclear ribosomal DNA provides a molecular tool for the identification of Schistosoma haematobium, Schistosoma guineensis and the hybrids of these two species. This molecular tool was utilized to provide a detailed analysis of the interactions between S. haematobium and S. guineensis in hybrid zones of Loum, Littoral Province, Cameroon. Individual hybrid schistosomes were identified within the natural populations collected from Loum in 1990, 1999 and 2000, which would have been misidentified as S. haematobium using solely morphological and sequence criteria. This study indicates the complexities of the hybridization between S. haematobium and S. guineensis and emphasizes the importance of assessing morphological, biological and molecular data to gain insights into the interaction of these two species over time.

  1. Schistosoma mansoni: Identification of SmNR4A, a member of nuclear receptor subfamily 4

    PubMed Central

    Wu, Wenjie; LoVerde, Philip T.

    2008-01-01

    A cDNA encoding a member of nuclear receptor subfamily 4 (SmNR4A) was isolated from the trematode Schistosoma mansoni. The open reading frame (ORF) of SmNR4A cDNA is 2481 base pairs long encoding an 827 amino acid protein. Alignment of the deduced protein sequence showed the DNA binding domain (DBD) of SmNR4A is highly conserved. Like human and Drosophila members in NR subfamily 4, SmNR4A possess an atypical ligand binding domain (LBD), the conserved lysine in helix H3 is replaced by a glutamic acid, and three of the four phenylalanines which fill the entire surface of the ligand binding pocket (LBP) are conserved in SmNR4A. A phylogenetic tree of SmNR4A was constructed using the conserved protein sequence of the DBD, the C-terminal-extension of DBD (CTE) and the LBD. The results show that the SmNR4A is a member of NR subfamily 4 from S. mansoni. The SmNR4A gene contains six exons spanning more than 50 kbp. The relative mRNA expression levels of SmNR4A were evaluated in fourteen different developmental stages by quantitative real-time reverse-transcriptase polymerase chain reaction (qPCR). The results demonstrated that SmNR4A expression was regulated throughout development. It was highly expressed in daughter sporocysts and 35-day worms, but barely expressed in cercariae and 1-hour and 3-day schistosomules. PMID:18682251

  2. Antiparasitic activity of menadione (vitamin K3) against Schistosoma mansoni in BABL/c mice.

    PubMed

    Kapadia, Govind J; Soares, Ingrid A O; Rao, G Subba; Badoco, Fernanda R; Furtado, Ricardo A; Correa, Mariana B; Tavares, Denise C; Cunha, Wilson R; Magalhães, Lizandra G

    2017-03-01

    Schistosomiasis is one of the neglected tropical diseases affecting nearly quarter of a billion people in economically challenged tropical and subtropical countries of the world. Praziquantel (PZQ) is the only drug currently available to treat this parasitic disease in spite being ineffective against juvenile worms and concerns about developing resistance to treat reinfections. Our earlier in vitro viability studies demonstrated significant antiparasitic activity of menadione (MEN) (vitamin K3) against Schistosoma mansoni adult worms. To gain insight into plausible mechanism of antischistosomal activity of MEN, its effect on superoxide anion levels in adult worms were studied in vitro which showed significant increases in both female and male worms. Further confirmation of the deleterious morphological changes in their teguments and organelles were obtained by ultrastructural analysis. Genotoxic and cytotoxic studies in male Swiss mice indicated that MEN was well tolerated at the oral dose of 500mg/kg using the criteria of MNPCE frequency and PCE/RBC ratio in the bone marrow of infected animals. The in vivo antiparasitic activity of MEN was conducted in female BALB/c mice infected with S. mansoni and significant reductions (P<0.001) in total worm burden were observed at single oral doses of 40 and 400mg/kg (48.57 and 61.90%, respectively). Additionally, MEN significantly reduced (P<0.001) the number of eggs in the liver of infected mice by 53.57 and 58.76%, respectively. Similarly, histological analysis of the livers showed a significant reduction (P<0.001) in the diameter of the granulomas. Since MEN is already in use globally as an over-the-counter drug for a variety of common ailments and a dietary supplement with a safety record in par with similar products when used in recommended doses, the above antiparasitic results which compare reasonably well with PZQ, make a compelling case for considering MEN to treat S. mansoni infection in humans.

  3. Reversible paralysis of Schistosoma mansoni by forchlorfenuron, a phenylurea cytokinin that affects septins

    PubMed Central

    Zeraik, Ana E.; Galkin, Vitold E.; Rinaldi, Gabriel; Garratt, Richard C.; Smout, Michael J.; Loukas, Alex; Mann, Victoria H.; Araujo, Ana P.U.; DeMarco, Ricardo; Brindley, Paul J.

    2014-01-01

    Septins are guanosine-5′-triphosphate-binding proteins involved in wide-ranging cellular processes including cytokinesis, vesicle trafficking, membrane remodeling and scaffolds, and with diverse binding partners. Precise roles for these structural proteins in most processes often remain elusive. Identification of small molecules that inhibit septins could aid in elucidating the functions of septins and has become increasingly important, including the description of roles for septins in pathogenic phenomena such as tumorigenesis. The plant growth regulator forchlorfenuron (FCF), a synthetic cytokinin known to inhibit septin dynamics, likely represents an informative probe for septin function. This report deals with septins of the human blood fluke Schistosoma mansoni and their interactions with FCF. Recombinant forms of three schistosome septins, SmSEPT5, SmSEPT7.2 and SmSEPT10, interacted with FCF, leading to rapid polymerization of filaments. Culturing developmental stages (miracidia, cercariae, adult males) of schistosomes in FCF at 50 – 500 μM rapidly led to paralysis, which was reversible upon removal of the cytokinin. The reversible paralysis was concentration-, time- and developmental stage-dependent. Effects of FCF on the cultured schistosomes were monitored by video and/or by an xCELLigence-based assay of motility, which quantified the effect of FCF on fluke motility. The findings implicated a mechanism targeting a molecular system controlling movement in these developmental stages: a direct effect on muscle contraction due to septin stabilization might be responsible for the reversible paralysis, since enrichment of septins has been described within the muscles of schistosomes. This study revealed the reversible effect of FCF on both schistosome motility and its striking impact in hastening polymerization of septins. These novel findings suggested routes to elucidate roles for septins in this pathogen, and exploitation of derivatives of FCF for anti

  4. Functional mapping of protein kinase A reveals its importance in adult Schistosoma mansoni motor activity.

    PubMed

    de Saram, Paulu S R; Ressurreição, Margarida; Davies, Angela J; Rollinson, David; Emery, Aidan M; Walker, Anthony J

    2013-01-01

    Cyclic AMP (cAMP)-dependent protein kinase/protein kinase A (PKA) is the major transducer of cAMP signalling in eukaryotic cells. Here, using laser scanning confocal microscopy and 'smart' anti-phospho PKA antibodies that exclusively detect activated PKA, we provide a detailed in situ analysis of PKA signalling in intact adult Schistosoma mansoni, a causative agent of debilitating human intestinal schistosomiasis. In both adult male and female worms, activated PKA was consistently found associated with the tegument, oral and ventral suckers, oesophagus and somatic musculature. In addition, the seminal vesicle and gynaecophoric canal muscles of the male displayed activated PKA whereas in female worms activated PKA localized to the ootype wall, the ovary, and the uterus particularly around eggs during expulsion. Exposure of live worms to the PKA activator forskolin (50 µM) resulted in striking PKA activation in the central and peripheral nervous system including at nerve endings at/near the tegument surface. Such neuronal PKA activation was also observed without forskolin treatment, but only in a single batch of worms. In addition, PKA activation within the central and peripheral nervous systems visibly increased within 15 min of worm-pair separation when compared to that observed in closely coupled worm pairs. Finally, exposure of adult worms to forskolin induced hyperkinesias in a time and dose dependent manner with 100 µM forskolin significantly increasing the frequency of gross worm movements to 5.3 times that of control worms (P≤0.001). Collectively these data are consistent with PKA playing a central part in motor activity and neuronal communication, and possibly interplay between these two systems in S. mansoni. This study, the first to localize a protein kinase when exclusively in an activated state in adult S. mansoni, provides valuable insight into the intricacies of functional protein kinase signalling in the context of whole schistosome physiology.

  5. Kinetics of interleukin-6 production after experimental infection of mice with Schistosoma mansoni.

    PubMed Central

    Khalil, R M; Hültner, L; Mailhammer, R; Luz, A; Moeller, J; Mohamed, A A; Omran, S; Dörmer, P

    1996-01-01

    It has been reported that interleukin-6 (IL-6) is expressed in cells of acute inflammatory granulomas experimentally induced in mice by eggs of Schistosoma mansoni. Moreover, in vitro IL-6 was shown to enhance the cytotoxic activity of human platelets against larvae of S. mansoni. To elucidate further a proposed biological significance of this cytokine during the course of schistosomiasis, we studied the kinetics of IL-6 production and concomitantly performed a histopathological analysis of the livers in BALB/c mice subcutaneously infected with S. mansoni cercariae. Over a period of 24 weeks postinfection (p.i.) we monitored serum IL-6 levels, IL-6 production in vitro by pokeweed mitogen (PWM)-stimulated spleen cells as well as IL-6 mRNA expression in livers, spleens and kidneys. We found significantly elevated IL-6 levels in PWM-stimulated spleen cell-conditioned media (SCM) at weeks 6 to 20 p.i., peaking at week 10 p.i. In contrast, serum IL-6 concentrations started to rise not before week 8 but remained significantly elevated above normal control values until week 24 p.i. The time pattern of enhanced IL-6 mRNA expression detected in spleens and livers, but not in kidneys, as well as the rises of IL-6 in SCM and with a delay of 2 weeks in serum samples correlated with the onset of the egg-induced inflammatory reactions as well as the incidence and the number of the granulomas observed histopathologically in the livers of infected mice. Our data emphasize both a local and a systemic role of IL-6 in the host immune response following infection of mice with S. mansoni. Images Figure 3 PMID:8943723

  6. Molecular cloning of Schistosoma mansoni calcineurin subunits and immunolocalization to the excretory system.

    PubMed

    Mecozzi, B; Rossi, A; Lazzaretti, P; Kady, M; Kaiser, S; Valle, C; Cioli, D; Klinkert, M Q

    2000-10-01

    In order to explain the schistosomicidal effect of cyclosporin A, the hypothesis was advanced that the drug, complexed with cyclophilin, inhibits the phosphatase activity of parasite calcineurin (CN), with mechanisms similar to those operating in its immunosuppressive action. As a preparatory step to the testing of this hypothesis, we report the molecular cloning of both CN subunits in Schistosoma mansoni. The catalytic (A) subunit has a predicted sequence of 607 amino acids and shows substantial similarity to other cloned CNs, except for the carboxy-terminal end that is highly divergent. The regulatory (B) subunit consists of 169 amino acids that are 86% identical to those of the human counterpart and, from its anomalous electrophoretic mobility, it appears to be myristoylated. The results of Southern blotting experiments are compatible with the existence of multiple genes for CNA and a single gene for CNB. Western blots showed that both subunits are present at all stages of the parasite life cycle and can be detected both in the soluble and in the membrane fraction. Immunofluorescence confocal microscopy revealed a striking concentration of the anti-CNA reactivity in 6-8 discrete spots in the schistosomula and in distinct spots along the body of the adult parasite, corresponding to the expected localization of flame cells. Both patterns were confirmed by a perfect co-localization of the anti-CNA signal with that of a previously characterized anti-flame cell monoclonal antibody. The preferential confinement of schistosome CN to the protonephridial system suggests that the enzyme in the parasite may fulfil similar functions to those performed in mammalian kidneys.

  7. A Meta-Analysis of Experimental Studies of Attenuated Schistosoma mansoni Vaccines in the Mouse Model

    PubMed Central

    Fukushige, Mizuho; Mitchell, Kate M.; Bourke, Claire D.; Woolhouse, Mark E. J.; Mutapi, Francisca

    2015-01-01

    Schistosomiasis is a water-borne, parasitic disease of major public health importance. There has been considerable effort for several decades toward the development of a vaccine against the disease. Numerous mouse experimental studies using attenuated Schistosoma mansoni parasites for vaccination have been published since 1960s. However, to date, there has been no syste