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Haruhiko Maruyama - One of the best experts on this subject based on the ideXlab platform.
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sequential changes in the host gut microbiota during infection with the intestinal parasitic nematode Strongyloides venezuelensis
Frontiers in Cellular and Infection Microbiology, 2019Co-Authors: Tanzila Afrin, Akina Hino, Haruhiko Maruyama, Yasunobu Maeda, Kazunori Murase, Asuka Kounosu, Vicky L Hunt, Mark Bligh, Isheng J TsaiAbstract:Soil-transmitted helminths (STHs) are medically important parasites that infect 1. 5 billion humans globally, causing a substantial disease burden. These parasites infect the gastrointestinal tract (GIT) of their host where they co-exist and interact with the host gut bacterial flora, leading to the coevolution of the parasites, microbiota, and host organisms. However, little is known about how these interactions change through time with the progression of infection. Strongyloidiasis is a human parasitic disease caused by the nematode Strongyloides stercoralis infecting 30-100 million people. In this study, we used a closely related rodent parasite Strongyloides venezuelensis and mice as a model of gastrointestinal parasite infection. We conducted a time-course experiment to examine changes in the fecal microbiota from the start of infection to parasite clearance. We found that bacterial taxa in the host intestinal microbiota changed significantly as the infection progressed, with an increase in the genera Bacteroides and Candidatus Arthromitus, and a decrease in Prevotella and Rikenellaceae. However, the microbiota recovered to the pre-infective state after parasite clearance from the host, suggesting that these perturbations are reversible. Microarray analysis revealed that this microbiota transition is likely to correspond with the host immune response. These findings give us an insight into the dynamics of parasite-microbiota interactions in the host gut during parasite infection.
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Additional file 4: of Secretome analysis of Strongyloides venezuelensis parasitic stages reveals that soluble and insoluble proteins are involved in its parasitism
2019Co-Authors: Yasunobu Maeda, Akina Hino, Juan E. Palomares-rius, Haruhiko Maruyama, Tanzila Afrin, Shakhinur Mondal, Ayako Nakatake, Taisei KikuchiAbstract:Table S3. List of proteins identified in the Strongyloides venezuelensis parasitic female excretory/secretory (E/S) insoluble fraction. (XLSX 18 kb
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Additional file 2: of Secretome analysis of Strongyloides venezuelensis parasitic stages reveals that soluble and insoluble proteins are involved in its parasitism
2019Co-Authors: Yasunobu Maeda, Akina Hino, Juan E. Palomares-rius, Haruhiko Maruyama, Tanzila Afrin, Shakhinur Mondal, Ayako Nakatake, Taisei KikuchiAbstract:Table S1. List of proteins identified in the Strongyloides venezuelensis infective third-stage larva (iL3) excretory/secretory (E/S) samples. (XLSX 80 kb
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Additional file 1: of Secretome analysis of Strongyloides venezuelensis parasitic stages reveals that soluble and insoluble proteins are involved in its parasitism
2019Co-Authors: Yasunobu Maeda, Akina Hino, Juan E. Palomares-rius, Haruhiko Maruyama, Tanzila Afrin, Shakhinur Mondal, Ayako Nakatake, Taisei KikuchiAbstract:Figure S1. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gel images of excretory/secretory (E/S) proteins from infective third-stage larvae (iL3s) and parasitic females (Pfs) of Strongyloides venezuelensis. iL3 proteins were collected from DMEM with/without proteinase inhibitors. Pf proteins were collected from secretions from worms incubated at 37 °C in PBS with or without proteinase inhibitors or at 4 °C without proteinase inhibitors. Figure S2. Stoma structure of infective third-stage larvae (iL3s) of Strongyloides venezuelensis a prior to induction, b 36 h post-induction with Dulbecco’s modified Eagle medium (DMEM) at 37 °C, c 36 h post-induction with DMEM at 37 °C with proteinase inhibitors and d in a nematode isolated from a rat’s (host’s) lung. Scale-bar: 20 μm. Table S4. Enriched gene ontology (GO) terms for the infective third-stage larva (iL3) samples. Table S5. Enriched gene ontology (GO) terms for the parasitic female soluble samples. (PDF 749 kb
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Karyotype and reproduction mode of the rodent parasite Strongyloides venezuelensis
2016Co-Authors: Akina Hino, Teruhisa Tanaka, Maho Takaishi, Yumiko Fujii, Juan E. Palomares-rius, Koichi Hasegawa, Haruhiko MaruyamaAbstract:Strongyloides venezuelensis is a parasitic nematode that infects rodents. Although Strongyloides species described to date are known to exhibit parthenogenetic reproduction in the parasitic stage of their life cycle and sexual reproduction in the free-living stage, we did not observe any free-living males in S. venezuelensis in our strain, suggesting that the nematode is likely to depend on parthenogenetic reproduction. We confirmed by cytological analysis that S. venezuelensis produces eggs by parthenogenesis during the parasitic stage of its life cycle. Phylogenetic analysis using nearly the full length of 18S and D3 region of 28S ribosomal RNA gene suggested that S. venezuelensis is distantly related to another rodent parasite, namely Strongyloides ratti, but more closely related to a ruminant parasite, Strongyloides papillosus. Karyotype analysis revealed S. venezuelensis reproduces with mitotic parthenogenesis, and has the same number of chromosomes as S. papillosus (2n = 4), but differs from S. ratti (2n = 6) in this regard. These results, taken together, suggest that S. venezuelensis evolved its parasitism for rodents independently from S. ratti and, therefore, is likely to have a different reproductive strategy. Key words: parthenogenesis, parasitic nematodes, karyotype
Lucia Helena Faccioli - One of the best experts on this subject based on the ideXlab platform.
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dexamethasone reduces bronchial wall remodeling during pulmonary migration of Strongyloides venezuelensis larvae in rats
Parasitology International, 2012Co-Authors: Cristiane Tefesilva, Em Floriano, Eleuza Rodrigues Machado, Marlene Tiduko Ueta, Lucia Helena Faccioli, Carlos Arterio Sorgi, Cristina T Beneli, Mara Rubia Nunes Celes, Simone G RamosAbstract:Strongyloidiasis is an intestinal parasitosis with an obligatory pulmonary cycle. A Th2-type immune response is induced and amplifies the cellular response through the secretion of inflammatory mediators. Although this response has been described as being similar to asthma, airway remodeling during pulmonary migration of larvae has not yet been established. The aim of this study was to identify the occurrence of airway remodeling during Strongyloides venezuelensis (S. v.) infection and to determine the ability of dexamethasone treatment to interfere with the mechanisms involved in this process. Rats were inoculated with 9,000 S. v. larvae, treated with dexamethasone (2 mg/kg) and killed at 1, 3, 5, 7, 14 and 21 days. Morphological and morphometric analyzes with routine stains and immunohistochemistry were conducted, and some inflammatory mediators were evaluated using ELISA. Goblet cell hyperplasia and increased bronchiolar thickness, characterized by edema, neovascularization, inflammatory infiltrate, collagen deposition and enlargement of the smooth muscle cell layer were observed. VEGF, IL1-β and IL-4 levels were elevated throughout the course of the infection. The morphological findings and the immunomodulatory response to the infection were drastically reduced in dexamethasone-treated rats. The pulmonary migration of S. venezuelensis larvae produced a transitory, but significant amount of airway remodeling with a slight residual bronchiolar fibrosis. The exact mechanisms involved in this process require further study.
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dexamethasone effects in the Strongyloides venezuelensis infection in a murine model
American Journal of Tropical Medicine and Hygiene, 2011Co-Authors: Eleuza Rodrigues Machado, Julia Maria Costacruz, Marlene Tiduko Ueta, Daniela Carlos, Carlos Arterio Sorgi, Simone G Ramos, David M Aronoff, Daniela I Souza, Edson Garcia Soares, Lucia Helena FaccioliAbstract:The aim of this study was to investigate the immunomodulatory effects of glucocorticoids on the immune response to Strongyloides venezuelensis in mice. Balb/c mice were infected with S. venezuelensis and treated with Dexamethasone (Dexa) or vehicle. Dexa treatment increased circulating blood neutrophil numbers and inhibited eosinophil and mononuclear cell accumulation in the blood, bronchoalveolar, and peritoneal fluid compared with control animals. Moreover, Dexa decreased tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-3 (IL-3), IL-4, IL-5, IL-10, and IL-12 production in the lungs and circulating immunoglobulin G1 (IgG1), IgG2a, and IgE antibody levels while increasing the overall parasite burden in the feces and intestine. Dexa treatment enhanced the fertility of female nematodes relative to untreated and infected mice. In summary, the alterations in the immune response induced by Dexa resulted in a blunted, aberrant immune response associated with increased parasite burden. This phenomenon is similar to that observed in S. stercoralis-infected humans who are taking immunosuppressive or antiinflammatory drugs, including corticosteroids.
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infectivity of Strongyloides venezuelensis is influenced by variations in temperature and time of culture
Experimental Parasitology, 2011Co-Authors: Eleuza Rodrigues Machado, Julia Maria Costacruz, Marlene Tiduko Ueta, Elaine Vicente Lourenco, Fernanda De Freitas Anibal, Maria Cristina Roquebarreira, Erica Vitalino Garcia Da Silva, Lucia Helena FaccioliAbstract:The present research investigated the influence of temperature and time of larvae culture on the infectivity of Strongyloides venezuelensis. Mice were infected s.c. with 1500 larvae of S. venezuelensis maintained at 28 °C for three days of culture (dc), 28 °C for seven dc or 18 °C for seven dc. On days 1, 3, 5, 7, 14 and 21 post-infection the animals were sacrificed and cell numbers in the blood, peritoneal cavity fluid (PCF), broncoalveolar fluid (BALF), cytokines, immunoglobulins, number of parasites and eggs/g of feces were quantified. Results demonstrated an increase in eosinophils and mononuclear cells in the blood, PCF and BALF of infected mice. Larvae at 28 °C/3dc induced earlier eosinophils in the PCF and BALF as opposed to larvae at 28 °C/7dc and 18 °C/7dc. Larvae at 28 °C/7dc induced higher synthesis of IL-4, IL-5 and IL-10 on days 5 and 7 post-infection. Larvae at 28 °C/3dc in culture induced higher synthesis of IL-12 than larvae of seven dc, but time in culture induced better synthesis of IFN-γ after larval migration had ceased and only adult worms were present. Larvae at 28 °C/3dc in culture induced higher synthesis of IgG and IgG1 and expelled less female parasites than larvae cultivated for seven days. In conclusion, it was observed that the infectivity of S. venezuelensis is influenced by variations in temperature and time of culture.
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cyclooxygenase derived mediators regulate the immunological control of Strongyloides venezuelensis infection
Fems Immunology and Medical Microbiology, 2010Co-Authors: Eleuza Rodrigues Machado, Marlene Tiduko Ueta, Daniela Carlos, Elaine V Lourenco, Gloria Emilia Petto De Souza, Carlos Arterio Sorgi, Erika V Silva, Simone G Ramos, David M Aronoff, Lucia Helena FaccioliAbstract:The aim of this study was to define the immunoregulatory role of prostaglandins in a mouse model of Strongyloides venezuelensis infection. Strongyloides venezuelensis induced an increase of eosinophils and mononuclear cells in the blood, peritoneal cavity fluid, and bronchoalveolar lavage fluid. Treatment with the dual cyclooxygenase (COX-1/-2) inhibitors indomethacin and ibuprofen, and the COX-2-selective inhibitor celecoxib partially blocked these cellular responses and was associated with enhanced numbers of infective larvae in the lung and adult worms in the duodenum. However, the drugs did not interfere with worm fertility. Cyclooxygenase inhibitors also inhibited the production of the T-helper type 2 (Th2) mediators IL-5, IgG1, and IgE, while indomethacin alone also inhibited IL-4, IL-10, and IgG2a. Cyclooxygenase inhibitors tended to enhance the Th1 mediators IL-12 and IFN-γ. This shift away from Th2 immunity in cyclooxygenase inhibitor-treated mice correlated with reduced prostaglandin E2 (PGE2) production in infected duodenal tissue. As PGE2 is a well-characterized driver of Th2 immunity, we speculate that reduced production of this lipid might be involved in the shift toward a Th1 phenotype, favoring parasitism by S. venezuelensis. These findings provide new evidence that cyclooxygenase-derived lipids play a role in regulating host defenses against Strongyloides, and support the exploration of eicosanoid signaling for identifying novel preventive and therapeutic modalities against these infections.
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counterregulation of th2 immunity by interleukin 12 reduces host defenses against Strongyloides venezuelensis infection
Microbes and Infection, 2009Co-Authors: Eleuza Rodrigues Machado, Marlene Tiduko Ueta, Daniela Carlos, Elaine V Lourenco, Carlos Arterio Sorgi, Erika V Silva, Simone G Ramos, David M Aronoff, Lucia Helena FaccioliAbstract:The aim of this study was to investigate the role of interleukin 12 (IL-12) during Strongyloides venezuelensis infection. IL-12(-/-) and wild-type C57BL/6 mice were subcutaneously infected with 1500 larvae of S. venezuelensis. On days 7, 14, and 21 post-infection, we determined eosinophil and mononuclear cell numbers in the blood and broncoalveolar lavage fluid (BALF), Th2 cytokine secretion in the lung parenchyma, and serum antibody levels. The numbers of eggs in the feces and worm parasites in the duodena were also quantified. The eosinophil and mononuclear cell counts and the concentrations of IL-3, IL-5, IL-10, IL-13, and IgG1 and IgE antibodies increased significantly in infected IL-12(-/-) and wild-type mice as compared with uninfected controls. However, the number of eosinophils and mononuclear cells in the blood and BALF and the Th2 cytokine levels in the lungs of infected IL-12(-/-) mice were greater than in infected wild-type C57BL/6 mice. In addition, serum IgE and IgG1 levels were also significantly enhanced in the infected mice lacking IL-12. Meanwhile, parasite burden and fecal egg counts were significantly decreased in infected IL-12(-/-) mice. Together, our results showed that the absence of IL-12 upregulates the Th2 immune response, which is important for control of S. venezuelensis infection.
Yukifumi Nawa - One of the best experts on this subject based on the ideXlab platform.
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Strongyloides venezuelensis longitudinal distribution of adult worms in the host intestine is influenced by mucosal sulfated carbohydrates
Experimental Parasitology, 2002Co-Authors: Haruhiko Maruyama, Mohamed Elmalky, Yoshifumi Hirabayashi, Sou Okamura, Mikiko Aoki, Tadashi Itagaki, Fukumi Nakamurauchiyama, Yukifumi Nawa, Shoichi Shimada, Nobuo OhtaAbstract:Abstract Mechanisms for the longitudinal distribution of parasitic females of Strongyloides venezuelensis in the host intestine were investigated in mice. Adult worms were mostly recovered from the anterior-most one-third of the small intestine throughout the infection after infective larvae inoculation. Surgically implanted adult worms established well in the small intestinal mucosa, either in the duodenum or in the ileum, whereas a few worms could establish in the large intestine. Implanted worms in the small intestine remained where they were implanted until expelled. Mucosal mast cells were induced in the whole small intestine after the worm implantation. In the large intestine, a considerable number of adult worms settled in the mucosa of mutant mice, whose goblet cell mucins were undersulfated because of a mutation in sulfate-activating enzymes. In these mice, the degree of sulfation of goblet cell mucins in the large intestine was significantly reduced to the level of normal small intestine goblet cell mucins. Our results suggest that sulfated glycoconjugates, either from mucosal mast cells or goblet cells, have important effects on the longitudinal distribution of parasitic females of S. venezuelensis . Index Descriptors and Abbreviations: Strongyloides venezuelensis ; Nematode; Tissue specificity; Goblet cell; Mucin; Mast cell; Sulfated carbohydrate; PBS, phosphate buffered saline.
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a role of mast cell glycosaminoglycans for the immunological expulsion of intestinal nematode Strongyloides venezuelensis
Journal of Immunology, 2000Co-Authors: Haruhiko Maruyama, Ayako Yoshida, Yukifumi Nawa, Yoshisada Yabu, Nobuo OhtaAbstract:We examined effects of mast cell glycosaminoglycans on the establishment of the intestinal nematode, Strongyloides venezuelensis, in the mouse small intestine. When intestinal mastocytosis occurred, surgically implanted adult worms could not invade and establish in the intestinal mucosa. In mast cell-deficient W/Wv mice, inhibition of adult worm invasion was not evident as compared with littermate +/+ control mice. Mucosal mastocytosis and inhibition of S. venezuelensis adult worm mucosal invasion was tightly correlated. To determine effector molecules for the invasion inhibition, adult worms were implanted with various sulfated carbohydrates including mast cell glycosaminoglycans. Among sulfated carbohydrates tested, chondroitin sulfate (ChS)-A, ChS-E, heparin, and dextran sulfate inhibited invasion of adult worms into intestinal mucosa in vivo. No significant inhibition was observed with ChS-C, desulfated chondroitin, and dextran. ChS-E, heparin, and dextran sulfate inhibited adhesion of S. venezuelensis adult worms to plastic surfaces in vitro. Furthermore, binding of intestinal epithelial cells to adhesion substances of S. venezuelensis, which have been implicated in mucosal invasion, was inhibited by ChS-E, heparin, and dextran sulfate. Because adult worms of S. venezuelensis were actively moving in the intestinal mucosa, probably exiting and reentering during infection, the possible expulsion mechanism for S. venezuelensis is inhibition by mast cell glycosaminoglycans of attachment and subsequent invasion of adult worms into intestinal epithelium.
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Strongyloides venezuelensis binding of orally secreted adhesion substances to sulfated carbohydrates
Experimental Parasitology, 1998Co-Authors: Haruhiko Maruyama, Yukifumi Nawa, Nobuo OhtaAbstract:Abstract Maruyama, H., Nawa, Y., and Ohta, N. 1998.Strongyloides venezuelensis: Binding of orally secreted adhesion substances to sulfated carbohydrates.Experimental Parasitology89,16–20. Adhesion substances produced by adult worms ofStrongyloides venezuelensisbound strongly to hepin-Sepharose beads after incubation at 37°C for 1 h. This binding was completely inhibited by highly sulfated carbohydrates such as soluble heparin, dextran surfate, fucoidan, and pentosan polysulfate. Chondroitin sulfate E and chondroitin sulfate A inhibited to a lesser degree and chondroitin sulfate C and dextran did not inhibit significantly. Carbohydrate moieties as well as the number and position of negatively charged sulfate groups of sulfated glycans were important determinants for the interaction between sulfated carbohydrates and adhesion substances. Adhesion substances ofS. venezuelensisadult worms also bound to negatively charged rat red blood cells. The binding was significantly inhibited by heparin but not by mono- or disaccharides. Thus the intraction between red cells and adhesion substances was electrostatic in nature, but did not involve lectin-sugar interactions.
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mucosal mast cells and the expulsive mechanisms of mice against Strongyloides venezuelensis
International Journal for Parasitology, 1993Co-Authors: A I Khan, Yoshiya Sato, Y Horii, Risa Tiuria, Yukifumi NawaAbstract:The possible importance of mucosal mast cells in the expulsive mechanisms of mice against Strongyloides venezuelensis was examined. After a primary infection by subcutaneous inoculation with various doses into C57BL/6 mice, about 50% of the initial dose of infective larvae (L3) became adult worms and, regardless of the dose of infection, they were completely expelled by Day 12 with similar kinetics. Intestinal mastocytosis at the time of expulsion was comparable among groups given different doses of infection. A kinetic study after infection with 2000 L3 in C57BL/6 mice revealed that mastocytosis started from Day 8, rapidly reached a peak on Day 12, and then gradually decreased. The strongest mastocytosis was observed in the upper one sixth of the small intestine where the majority of adult worms parasitized. Over 80% of mast cells induced by the infection were located in the intestinal epithelial layer. When mast cell-deficient W/Wv and their normal littermate +/+ mice were infected with 1000 L3, expulsion was significantly delayed in W/Wv mice, though adult worms were eventually expelled by Day 18 in W/Wv mice. Delayed expulsion as well as defective mast cell responses of W/Wv mice were completely restored by bone marrow grafting 10 weeks prior to infection. These results show that, like S. ratti infection, intestinal mucosal mast cells are important in causing expulsion of S. venezuelensis.
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persistent infection of Strongyloides venezuelensis and normal expulsion of nippostrongylus brasiliensis in mongolian gerbils meriones unguiculatus with reference to the cellular responses in the intestinal mucosa
Parasite Immunology, 1993Co-Authors: Y Horii, A I Khan, Yukifumi NawaAbstract:Summary The kinetics of daily faecal egg count, worm burdens, and intestinal cellular responses were examined in Mongolian gerbils after infection with either Strongyloides venezuelensis or Nippostrongylus brasiliensis alone, or concurrently with both parasites. The results show that, both in individual and concurrent infections, S. venezuelensis infection persisted for over 10 weeks and elicited a gradual increase in number of mast cells in the jejunal mucosa. On the other hand, N. brasiliensis worms were expelled by 3 weeks in association with goblet cell hyperplasia. These results suggest that effector/regulator cells involved in worm expulsion are different and highly selective depending on the genus of intestinal helminths.
Nobuo Ohta - One of the best experts on this subject based on the ideXlab platform.
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successive changes in tissue migration capacity of developing larvae of an intestinal nematode Strongyloides venezuelensis
Parasitology, 2005Co-Authors: Haruhiko Maruyama, A Nishimaki, Y Takuma, M Kurimoto, Takashi Suzuki, Y Sakatoku, Masahiro Ishikawa, Nobuo OhtaAbstract:Infective larvae of an intestinal nematode, Strongyloides venezuelensis, enter rodent hosts percutaneously, and migrate through connective tissues and lungs. Then they arrive at the small intestine, where they reach maturity. It is not known how S. venezuelensis larvae develop during tissue migration. Here we demonstrate that tissue invasion ability of S. venezuelensis larvae changes drastically during tissue migration, and that the changes are associated with stage-specific protein expression. Infective larvae, connective tissue larvae, lung larvae, and mucosal larvae were used to infect mice by various infection methods, including percutaneous, subcutaneous, oral, and intraduodenal inoculation. Among different migration stages, only infective larvae penetrated mouse skin. Larvae, once inside the host, quickly lost skin penetration ability, which was associated with the disappearance of an infective larva-specific metalloprotease. Migrating larvae had connective tissue migration ability until in the lungs, where larvae became able to settle down in the intestinal mucosa. Lung larvae and mucosal larvae were capable of producing and secreting adhesion molecules.
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il 18 with il 2 protects against Strongyloides venezuelensis infection by activating mucosal mast cell dependent type 2 innate immunity
Journal of Experimental Medicine, 2005Co-Authors: Yuki Sasaki, Haruhiko Maruyama, Nobuo Ohta, Tatsuya Tegoshi, Naoki Arizono, Tomohiro Yoshimoto, Kenji NakanishiAbstract:C57BL/6 (B6) and B6 background STAT6 − / − mice pretreated with IL-18 plus IL-2 showed prominent intestinal mastocytosis and rapidly expelled implanted adult worms of the gastrointestinal nematode Strongyloides venezuelensis . In contrast, identically pretreated mast cell–deficient W/Wv mice failed to do so. Thus, activated mucosal mast cells (MMC) are crucial for parasite expulsion. B6 mice infected with S. venezuelensis third-stage larvae (L3) completed parasite expulsion by day 12 after infection, whereas IL-18 − / − or IL-18R α − / − B6 mice exhibited marked impairment in parasite expulsion, suggesting a substantial contribution of IL-18–dependent MMC activation to parasite expulsion. Compared with IL-18 − / − or IL-18R α − / − mice, S. venezuelensis L3–infected STAT6 − / − mice have poorly activated MMC and sustained infection; although their IL-18 production is normal. Neutralization of IL-18 and IL-2 further reduces expulsion in infected STAT6 − / − mice. These results suggest that collaboration between IL-18–dependent and Th2 cell–dependent mastocytosis is important for prompt parasite expulsion.
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Strongyloides venezuelensis longitudinal distribution of adult worms in the host intestine is influenced by mucosal sulfated carbohydrates
Experimental Parasitology, 2002Co-Authors: Haruhiko Maruyama, Mohamed Elmalky, Yoshifumi Hirabayashi, Sou Okamura, Mikiko Aoki, Tadashi Itagaki, Fukumi Nakamurauchiyama, Yukifumi Nawa, Shoichi Shimada, Nobuo OhtaAbstract:Abstract Mechanisms for the longitudinal distribution of parasitic females of Strongyloides venezuelensis in the host intestine were investigated in mice. Adult worms were mostly recovered from the anterior-most one-third of the small intestine throughout the infection after infective larvae inoculation. Surgically implanted adult worms established well in the small intestinal mucosa, either in the duodenum or in the ileum, whereas a few worms could establish in the large intestine. Implanted worms in the small intestine remained where they were implanted until expelled. Mucosal mast cells were induced in the whole small intestine after the worm implantation. In the large intestine, a considerable number of adult worms settled in the mucosa of mutant mice, whose goblet cell mucins were undersulfated because of a mutation in sulfate-activating enzymes. In these mice, the degree of sulfation of goblet cell mucins in the large intestine was significantly reduced to the level of normal small intestine goblet cell mucins. Our results suggest that sulfated glycoconjugates, either from mucosal mast cells or goblet cells, have important effects on the longitudinal distribution of parasitic females of S. venezuelensis . Index Descriptors and Abbreviations: Strongyloides venezuelensis ; Nematode; Tissue specificity; Goblet cell; Mucin; Mast cell; Sulfated carbohydrate; PBS, phosphate buffered saline.
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Strongyloides venezuelensis heparin binding adhesion substances in immunologically damaged adult worms
Experimental Parasitology, 2000Co-Authors: Haruhiko Maruyama, Hisanori Hatano, Takashi Kumagai, Mohamed Elmalky, Ayako Yoshida, Nobuo OhtaAbstract:Abstract Maruyawa, H., Hatano, H., Kumagai, T., El-Malky, M., Yoshida, A., and Ohta, N. 2000. Strongyloides venezuelensis: Heparin-binding adhesion substances in immunologically damaged adult worms. Experimental Parasitology 95, 170–175. Immunologically damaged Strongyloides venezuelensis adult worms were examined for their mucosal invasion ability and secretion of heparin-binding adhesion substances. S. venezuelensis was expelled from male Wistar rats 4 to 5 weeks after infection. Four-week-old adult worms were smaller and had fewer eggs than 1-week-old adult worms. One-week-old, 4-week-old, and 5-week-old adult worms equally established in the recipient mouse intestine when surgically implanted. Adult worms of 4 and 5 weeks of age secreted adhesion substances as much as 1-week-old adult worms. There was no difference in the heparin-binding activities and the lectin-binding profile of adhesion substances among adult worms of different ages. The rate of secretion of adhesion substances from the mouth was also identical. Heparin-binding activities were detected in crude adult worm proteins; however, proteins of 5-week-old adult worms had weaker heparin-binding activities than those of 1-week-old adult worms. Western blotting revealed that a number of heparin-binding proteins were lost in 5-week-old adult worms. A heparin-binding protein of 42.0 kDa, which was consistently expressed in adult worms, was a possible component of heparin-binding adhesion substances which are secreted from the mouth.
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protective mechanisms against the intestinal nematode Strongyloides venezuelensis in schistosoma japonicum infected mice
Parasite Immunology, 2000Co-Authors: Haruhiko Maruyama, Ayako Yoshida, Yoshio Osada, Mitsuru Futakuchi, Hitoshi Kawaguchi, Renli Zhang, Tomoyuki Shirai, Somei Kojima, Nobuo OhtaAbstract:Mice infected with Schistosoma japonicum were resistant to the intestinal nematode, Strongyloides venezuelensis. The numbers of adult S. venezuelensis recovered from mice were significantly decreased when infections were given from 6 weeks after S. japonicum infection. Larval recovery from the lungs showed that significant numbers of subcutaneously inoculated S. venezuelensis larvae were eliminated by 3 days in S. japonicum-infected mice (P < 0.0001), while histology revealed that this was associated with massive eosinophilic infiltration in the lungs. In addition, adult S. venezuelensis worms implanted in the duodenum of S. japonicum-infected mice could not establish in the intestine. This failure was associated with mucosal mastocytosis. Activation of eosinophils and intestinal mast cells was correlated with elevated expression of mRNA for interleukin (IL)-3, IL-4, and IL-5 in S. japonicum-infected mice. Sera from S. japonicum-infected mice recognized S. venezuelensis larva antigens as strongly as those from S. venezuelensis-infected mice, although transfer of sera from S. japonicum-infected mice to normal recipient mice did not protect them from S. venezuelensis challenge infection. It was concluded that the mechanisms for larval killing and adult worm expulsion of S. venezuelensis in S. japonicum-infected mice were identical to those seen in infections with S. venezuelensis only.
Alan Lane De Melo - One of the best experts on this subject based on the ideXlab platform.
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treatment with nitric oxide donors diminishes hyperinfection by Strongyloides venezuelensis in mice treated with dexamethasone
Acta Tropica, 2015Co-Authors: Alan Lane De Melo, Julio Lopezaban, Ana Lucia Ruano, Pedro Fernandezsoto, Antonio MuroAbstract:The effects of using nitric oxide (NO) donors and inhibitors in experimental strongyloidiasis were showed using, both naive and dexamethasone immunosuppressed BALB/c mice infected with Strongyloides venezuelensis. Aminoguanidine, an inhibitor of inducible NO synthase and LA419 a NO donor, were administered. Dexamethasone was used to induce immunosuppression. The study in BALB/c mice revealed increases in counts of fecal eggs, larvae in lungs and parasitic females following treatment with aminoguanidine, while mice treated with LA419 had limited egg output with low larval and adult recoveries. Mice immunosuppressed with dexamethasone developed hyperinfection with high long lasting fecal egg emission, high numbers of larvae in lungs and high numbers of parasitic females in the intestine even when the infection had already been cleared in non-immunosuppressed infected controls. Mice treated with dexamethasone and aminoguanidine had the highest egg output and the highest larva and parasitic female recovery showing a severe hyperinfection syndrome. In contrast, treatment with dexamenthasone and LA419 resulted in a controlled hyperinfection syndrome and these mice were able to eliminate the parasite. Therefore, NO modulation appears to be a determinant factor in severe strongyloidiasis and further studies should be conducted to confirm in other experimental models.
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destruicao de larvas infectantes de Strongyloides venezuelensis pelos fungos duddingtonia flagrans arthrobotrys robusta e monacrosporium sinense
Revista Da Sociedade Brasileira De Medicina Tropical, 2011Co-Authors: Fabio Ribeiro Braga, Juliana Milani Araujo, Andre R Silva, Jackson Victor De Araujo, Rogerio Oliva Carvalho, Alexandre De Oliveira Tavela, Manoel Eduardo Da Silva, Fernanda Mara Fernandes, Alan Lane De MeloAbstract:INTRODUCTION: Strongyloides venezuelensis has been used as a model for studying human strongyloidosis. METHODS: This study aimed to compare the ability of predatory nematophagous fungi Duddingtonia flagrans (AC001), Arthrobotrys robusta (I-31) and Monacrosporium sinense (SF53) and on infective larvae (L3) of Strongyloides venezuelensis in laboratory conditions on 2% water-agar medium. RESULTS: At the end of the experiment, the percentage reductions of Strongyloides venezuelensi L3 were: 93% (AC001), 77.2% (I-31) and 65.2% (SF53). CONCLUSIONS: The nematophagous fungi were able to capture and destroy the L3 in vitro and can be used as biological controllers of Strongyloides venezuelensi.
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destruction of Strongyloides venezuelensis infective larvae by fungi duddingtonia flagrans arthrobotrys robusta and monacrosporium sinense
Revista Da Sociedade Brasileira De Medicina Tropical, 2011Co-Authors: Fabio Ribeiro Braga, Juliana Milani Araujo, Andre R Silva, Jackson Victor De Araujo, Rogerio Oliva Carvalho, Alexandre De Oliveira Tavela, Manoel Eduardo Da Silva, Fernanda Mara Fernandes, Alan Lane De MeloAbstract:INTRODUCTION: Strongyloides venezuelensis has been used as a model for studying human strongyloidosis. METHODS: This study aimed to compare the ability of predatory nematophagous fungi Duddingtonia flagrans (AC001), Arthrobotrys robusta (I-31) and Monacrosporium sinense (SF53) and on infective larvae (L3) of Strongyloides venezuelensis in laboratory conditions on 2% water-agar medium. RESULTS: At the end of the experiment, the percentage reductions of Strongyloides venezuelensi L3 were: 93% (AC001), 77.2% (I-31) and 65.2% (SF53). CONCLUSIONS: The nematophagous fungi were able to capture and destroy the L3 in vitro and can be used as biological controllers of Strongyloides venezuelensi.
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Strongyloides venezuelensis efeito de antimicrobiano e imunossupressor no curso da infeccao em camundongos da linhagem akr j
Revista de Ciências Médicas e Biológicas, 2009Co-Authors: W A Martins, Jacques Robert Nicoli, Luiz De Macedo Farias, M A R Carvalho, Denise Carmona Cara, Alan Lane De MeloAbstract:Groups of AKR/J strain of mice infected by Strongyloides venezuelensis and treated with Ceftazidima, Dexametasona or with both drugs concomitantly had been killed on 3rd, 7th and 12th day after infection and their lungs and intestines were processed for histological studies. In lungs of all infected groups, it was verified an inflammatory infiltrated (neutrophils and mononuclear cells) in the third day after the infection. In 7th and 12th day after the infection, the inflammatory reaction becomes reduced in control and antimicrobial treated groups, but not in immunosuppressed animals (with or without antimicrobial treatment). Analysis of the duodenal mucosa confirmed the presence of parasites in all groups of animals. On the 7th day after infection it was observed significant alterations in the small intestine of control (infected) and infected and treated with antimicrobial groups with presence of inflammatory foci, constituted by mononuclear and eosinophils in mucosa, associate to a large amount of parasites, mainly in the region of the epithelium and sub epithelium. Two others groups (infected and immunosuppressed mice with or without antimicrobial), did not present inflammatory process. Goblet cells were less evident in mucosa suggesting a reduction in mucous production. In the 12th day of the infection, the treated with antimicrobial and control groups presented a reduced number of parasites and a discrete inflammatory reaction in the small intestine while the immunosuppressed groups showed more parasites in duodenum. The permanence of the infection by S. venezuelensis in immunosuppressed animals was prolonged in relation to other groups, remaining until the 49th day after infection. The results indicate that the interference of treatments in the population of intestinal microbiota favours the parasitism by Strongyloides venezuelensis.
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alteracoes histopatologicas em camundongos akr j reinfectados por Strongyloides venezuelensis
Revista de Ciências Médicas e Biológicas, 2006Co-Authors: Alan Lane De Melo, Anilton Cesar Vasconcelos, Sandro Eugenio Pereira GazzinelliAbstract:AKR/J mice, reinfected with 500 filariform larvae (L3) of Strongyloides venezuelensis, developed a strong inflammatory reaction in the lungs and intestine on day 7 post-reinfection. When mice were treated with dexamethasone, it was not verified inflammatory reactions in the lungs or intestine. Results indicate that the inflammatory reaction in lungs and intestine play an important role in decreasing the parasitic population during reinfection with S venezuelensis. in AKR/J mice, fact that is not verified when these mice are treated with dexametasona and has its inflammatory responses suppressed or depressed.
