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Sample records for oncospheres

  1. Vaccination with hatched but non-activated, non-viable oncospheres of Taenia taeniaeformis in rats.

    Science.gov (United States)

    Ito, A; Hashimoto, A

    1993-06-01

    The usefulness of hatched but non-activated oncospheres as a candidate vaccine was evaluated using a Taenia taeniaeformis/rat system, since preparation of these oncospheres in vitro is known to be very simple. The findings were: (1) rats vaccinated with non-viable oncospheres became completely resistant to challenge infection; (2) intra-venous injection was the most effective to induce complete resistance; (3) a single oncosphere was sufficient to induce complete resistance in infected rats, whereas approximately 50 and 500 non-viable oncospheres were required to evoke strong and complete resistance, respectively, in vaccinated rats. The usefulness of non-viable oncospheres without adjuvant is discussed.

  2. Hymenolepis nana: immunity against oncosphere challenge in mice previously given viable or non-viable oncospheres of H. nana, H. diminuta, H. microstoma and Taenia taeniaeformis.

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    Ito, A; Onitake, K; Sasaki, J; Takami, T

    1991-04-01

    When mice, previously given oral inoculation with viable oncospheres of the heterologous cestode species (Hymenolepis diminuta, H. microstoma, Taenia taeniaeformis) and the homologous one (H. nana), were challenged with oncospheres of H. nana 4 days after the primary inoculation, they showed strong and complete resistance to H. nana challenge, respectively. However, the resistance was not evoked in mice given either infective eggs of Toxocara canis or non-viable oncospheres of all cestode species examined. Congenitally athymic nude mice given viable oncospheres did not show any resistance to H. nana either. Eosinophil infiltration around cysticercoids of H. nana in the intestinal villi appeared to be more prominent in mice previously given viable oncospheres of H. diminuta than in mice given non-viable oncospheres or PBS only. Some of the eosinophils in the villus harboring cysticercoid(s) of H. nana invaded the epithelia in the former, whereas all eosinophils remained in the lamina propria in the latter. There was almost no eosinophil infiltration in nude mice. Microscopic observations revealed that oncospheres of H. diminuta, which require beetles as the intermediate host like H. microstoma, could invade the mouse intestinal tissue. Therefore, it is strongly suggested that the strong cross resistance to H. nana in mice, induced by oncospheres of all heterologous cestode species, is thymus-dependent and due to oncospheral invasion into the intestinal tissue of mice.

  3. The role of dissolved carbon dioxide and whole bile in the in vitro activation of Taenia taeniaeformis oncospheres.

    Science.gov (United States)

    Ishiwata, K; Oku, Y; Kamiya, M

    1993-12-01

    Dissolved carbon dioxide was deemed not to be an important factor in the activation of Taenia taeniaeformis oncospheres. Rabbit bile was found to provide the most appropriate whole bile for in vitro activation of oncospheres.

  4. Molecular cloning of Taenia taeniaeformis oncosphere antigen genes.

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    Cougle, W G; Lightowlers, M W; Bogh, H O; Rickard, M D; Johnson, K S

    1991-03-01

    Infection of mice with the cestode Taenia taeniaeformis exhibits several important features common to other cestode infections, including the ability to vaccinate with crude antigen mixtures. Partial purification of the protective oncosphere antigens has been reported with a cutout from deoxycholate (DOC) acrylamide gels; this cutout was called fraction II (FII), and comprises approximately 10% of total DOC-soluble oncosphere antigen. Western blots of DOC gels probed with anti-FII antisera revealed a series of 3-5 discrete bands within the FII region. Further fractionation of the FII antigens on DOC gels was impractical due to limitations in supply of oncospheres, so a cDNA library was constructed from 150 ng of oncosphere mRNA and screened with alpha-FII antisera. Two distinct clone families were identified, oncA and oncB. Antibodies affinity-purified on either of two representative members, oncA1 and oncB1, recognised all the FII bands. Individual FII bands excised from a DOC gel resolved into an overlapping series of molecules when re-run on SDS-PAGE, indicating that each FII band consisted of several polypeptides of differing molecular weight. Immunoprecipitates resolved on SDS-PAGE revealed that alpha-FII recognised 3 major oncosphere antigens, of 62, 34 and 25 kDa; antisera against oncB precipitated both the 34- and 25-kDa antigens, whereas alpha-oncA antisera precipitated the 62-kDa antigen. We conclude that oncA and oncB encode the major antigens in the FII complex. The 62-kDa antigen encoded by oncA1 was the only common antigen precipitated by anti-FII and two other antisera raised against different protective extracts, suggesting that it may be a protective component in all three. Southern blot results indicate that oncA and oncB are distinct genes present at low copy number in the genome. Evidence is also presented suggesting that some cestode mRNAs, including oncA, may use variant polyadenylation signals.

  5. Taenia taeniaeformis: immunoprecipitation analysis of the protein antigens of oncospheres and larvae.

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    Bowtell, D D; Mitchell, G F; Anders, R F; Lightowlers, M W; Rickard, M D

    1983-12-01

    Biosynthetically or exogenously labeled proteins and immunoprecipitated protein antigens of established 28-day-old larvae of Taenia taeniaeformis were compared with proteins and antigens of infective oncospheres using single and two-dimensional gel electrophoresis. Immunoprecipitation was carried out using sera from infected mice and mouse antisera raised to larvae or oncospheres, and emphasis was placed on identifying antigens common to both oncospheres and larvae. Two major larval antigens of Mr 40,000 and 200,000, designated Tt40 and Tt200, are common to somatic larval preparations and oncospheres. Additionally, two major oncosphere antigens of Mr 55,000 and 60,000, designated Tt55 and Tt60, are also present in larval excretory and secretory (i.e., ES or exoantigen) products. Information obtained from these immunoprecipitation analyses will facilitate isolation and production of common as well as stage-specific protein antigens in the development of defined-antigen vaccines in this model system of cysticercosis.

  6. Protective antibodies against Taenia taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres.

    Science.gov (United States)

    Ito, A; Asano, K; Okamoto, K

    1994-09-01

    Antibody responses against Taenia taeniaeformis in rats infected with eggs or injected with non-viable oncospheres or recombinant antigens of oncospheres were analysed by passive transfer of serum and Western blotting. When recipient rats were injected with 1 ml serum from donors infected with eggs (infected serum), they all showed complete resistance to oral egg challenge, whereas those injected with 1 ml serum from donors injected with either oncospheres or recombinant antigens (vaccinated serum) showed no resistance. IgG and IgG subclass responses detected by Western blotting revealed that antibody responses to oncosphere antigens in infected serum thoroughly differed from those in vaccinated serum. It is suggested that IgG2 alpha responses in infected serum should be used for screening of epitopes for candidate vaccine.

  7. Variation in the cellular localization of host-protective oncospheral antigens in Taenia saginata and Taenia solium.

    Science.gov (United States)

    Jabbar, A; Verástegui, M; Lackenby, J A; Walduck, A K; Gauci, C G; Gilman, R H; Lightowlers, M W

    2010-01-01

    Immunohistochemistry and immunofluorescence with confocal microscopy were used to localize the host-protective antigens of Taenia saginata (TSA9 and TSA18) and Taenia solium (TSOL16, TSOL18 and TSOL45). In nonactivated oncospheres, TSA9 and TSOL45 antigens were found primarily in the cytoplasm of the penetration gland type one (PG1) cell. A similar pattern of staining was seen for TSOL45 in oncospheres of T. solium that remained within the oncospheral membrane. In addition, there was less intense staining of TSA9 and TSOL45 in the quadri-nucleate penetration gland type 2 (PG2) cell. TSA18, TSOL16 and TSOL18 were predominantly found in the PG2 cell. In activated oncospheres that had escaped the oncospheral membrane, the antigens (other than TSA9) were seen both in the penetration gland cell locations and throughout the oncospheral parenchyma. Co-localization analyses revealed that only TSOL16 and TSOL18 antigens were co-localized in the PG2 cell of oncospheres that had not escaped the oncospheral membrane. However, in activated oncospheres that escaped the oncospheral membrane, all three antigens of T. solium were co-localized as they were present throughout the parenchyma. No positive staining was observed on the surface of nonactivated or recently activated oncospheres of T. saginata or T. solium.

  8. Immunization of Rodents Against Hymenolepis Infections using Non-Viable Homologous Oncospheres

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    Ping-Chin Fan

    2004-12-01

    Full Text Available Immunity to Taiwan Taenia infection in pigs can be stimulated using homologous or heterologous nonviable Taenia oncospheres. This study was designed to determine whether homologous non-viable oncospheres could stimulate immunity to Hymenolepis infection in rodents. Hatched oncospheres were prepared from eggs of Hymenolepis diminuta, Hymenolepis nana, and Hymenolepis microstoma and kept at −70°C for more than 1 month. A mixture of 500 non-viable oncospheres of each tapeworm and complete Freund's adjuvant was injected subcutaneously in four groups of Sprague-Dawley rats or ICR mice one to four times at an interval of 1 week; controls were not immunized. After immunization, each rodent was orally inoculated with three fresh active cysticercoids of H. diminuta or H. microstoma or 500 fresh eggs of H. nana. The animals were then necropsied for adult tapeworms. No rats or mice immunized with non-viable oncospheres of H. diminuta or H. nana were infected by the challenge inoculation. However, 28 of 34 mice immunized with non-viable H. microstoma oncospheres were infected after inoculation with cysticercoids. This study demonstrated complete protection against infection by homologous parasites in rats or mice immunized with non-viable oncospheres of H. diminuta and H. nana, respectively. Repeated immunization may not be required if resistance is stimulated in rodent hosts.

  9. Immunization of rodents against Hymenolepis infections using non-viable homologous oncospheres.

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    Fan, Ping-Chin; Chung, Wen-Cheng; Ito, Akira

    2004-12-01

    Immunity to Taiwan Taenia infection in pigs can be stimulated using homologous or heterologous non-viable Taenia oncospheres. This study was designed to determine whether homologous non-viable oncospheres could stimulate immunity to Hymenolepis infection in rodents. Hatched oncospheres were prepared from eggs of Hymenolepis diminuta, Hymenolepis nana, and Hymenolepis microstoma and kept at -70 degrees C for more than 1 month. A mixture of 500 non-viable oncospheres of each tapeworm and complete Freund's adjuvant was injected subcutaneously in four groups of Sprague-Dawley rats or ICR mice one to four times at an interval of 1 week; controls were not immunized. After immunization, each rodent was orally inoculated with three fresh active cysticercoids of H. diminuta or H. microstoma or 500 fresh eggs of H. nana. The animals were then necropsied for adult tapeworms. No rats or mice immunized with non-viable oncospheres of H. diminuta or H. nana were infected by the challenge inoculation. However, 28 of 34 mice immunized with non-viable H. microstoma oncospheres were infected after inoculation with cysticercoids. This study demonstrated complete protection against infection by homologous parasites in rats or mice immunized with non-viable oncospheres of H. diminuta and H. nana, respectively. Repeated immunization may not be required if resistance is stimulated in rodent hosts.

  10. Characterization of the carbohydrate components of Taenia solium oncosphere proteins and their role in the antigenicity.

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    Arana, Yanina; Verastegui, Manuela; Tuero, Iskra; Grandjean, Louis; Garcia, Hector H; Gilman, Robert H

    2013-10-01

    This study examines the carbohydrate composition of Taenia solium whole oncosphere antigens (WOAs), in order to improve the understanding of the antigenicity of the T. solium. Better knowledge of oncosphere antigens is crucial to accurately diagnose previous exposure to T. solium eggs and thus predict the development of neurocysticercosis. A set of seven lectins conjugates with wide carbohydrate specificity were used on parasite fixations and somatic extracts. Lectin fluorescence revealed that D-mannose, D-glucose, D-galactose and N-acetyl-D-galactosamine residues were the most abundant constituents of carbohydrate chains on the surface of T. solium oncosphere. Lectin blotting showed that posttranslational modification with N-glycosylation was abundant while little evidence of O-linked carbohydrates was observed. Chemical oxidation and enzymatic deglycosylation in situ were performed to investigate the immunoreactivity of the carbohydrate moieties. Linearizing or removing the carbohydrate moieties from the protein backbones did not diminish the immunoreactivity of these antigens, suggesting that a substantial part of the host immune response against T. solium oncosphere is directed against the peptide epitopes on the parasite antigens. Finally, using carbohydrate probes, we demonstrated for the first time that the presence of several lectins on the surface of the oncosphere was specific to carbohydrates found in intestinal mucus, suggesting a possible role in initial attachment of the parasite to host cells.

  11. Taenia taeniaeformis: effectiveness of staining oncospheres is related to both temperature of treatment and molecular weight of dyes utilized.

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    Chapalamadugu, Kalyan C; Busboom, Jan R; Nelson, Mark L; Hancock, Dale D; Tang, Juming; Jasmer, Douglas P

    2008-02-14

    Methods to determine viability of taeniid oncospheres following treatments with potential lethality have practical application in efforts to control transmission. Here we investigated several methods, in lieu of infectivity studies, to assess oncosphere viability and determine lethal temperature treatment regimens. In the first experiment, a standard treatment to exshell oncospheres with 0.5% hypochlorite was assessed for influence on oncosphere recovery of Taenia taeniaeformis eggs. Recovery of eggs and exshelled oncospheres decreased with increasing time in hypochlorite, which indicated that hypochlorite can damage eggs and oncospheres, translating into potential overestimation of lethality of experimental treatments. Losses in hypochlorite were accentuated when eggs were pretreated at 75 degrees C, but not lower temperatures, including 65 degrees C, indicating a sharp threshhold between 65 degrees C and 75 degrees C where eggs and oncospheres became hypersensitive to subsequent hypochlorite treatment. To further investigate this change in relation to temperature, non-vital (acridine orange, AO) and vital (propidium iodide, PI; trypan blue, TB) dyes were used to assess staining of oncospheres (exshelled or not) under conditions ranging from room temperature up to 95 degrees C. The behaviors of dyes as related to internal staining of oncospheres were described using non-linear regression and a sigmoid four-parametric model to determine the inflection point (T50). Each of the dyes differed significantly in T50 estimates, e.g. AO (69.22+/-0.53), PI (73.89+/-0.52) and TB (79.43+/-0.45). For these dyes, the T50 increased in relation to the increasing molecular weight of the dyes. Collectively, the results suggested that barriers to chemical permeability exist in eggs that breakdown incrementally with increasing temperatures above 65 degrees C. This staining behavior and the likelihood that the temperatures involved are above a lethal threshhold clarify a basic

  12. Cross protection against Taenia taeniaeformis in rats vaccinated with non-viable oncospheres of Asian Taenia or T. saginata.

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    Ito, A; Fan, P C; Chung, W C; Suzuki, M

    1994-03-01

    It was determined to examine whether rats injected with non-viable oncospheres of Asian Taenia or Taenia saginata became resistant to challenge infection with eggs of Taenia taeniaeformis, since (a) metacestodes of Asian Taenia and T. taeniaeformis develop in the liver of pigs and rats, respectively, and (b) Asian Taenia and T. saginata have human origins. Rats injected intravenously or subcutaneously with complete Freund's adjuvant with non-viable oncospheres of Asian Taenia showed statistically significant resistance to challenge infection with eggs of T. taeniaeformis, whereas those injected with non-viable oncospheres of T. saginata did not show any resistance.

  13. In vitro hatching of oncospheres of Taenia taeniaeformis using eggs isolated from fresh, frozen, formalin-fixed and ethanol-fixed segments.

    Science.gov (United States)

    Negita, T; Ito, A

    1994-09-01

    In order to establish a simple means of handling eggs of taeniid cestodes under non-biohazardous conditions, gravid segments of Taenia taeniaeformis were fixed in ethanol or formalin or were frozen. In vitro hatching of oncospheres was carried out by the 0.5% sodium hypochlorite method using eggs isolated from the nonviable and viable segments. No oncospheres hatched from formalized eggs, whereas almost all oncospheres hatched from all other eggs but the number of oncospheres recovered was highly variable. Oncospheres hatched from eggs isolated from frozen segments were highly fragile. The highest figures for in vitro hatching of oncospheres were recorded when eggs isolated either from segments fixed in 70% ethanol or from viable segments were used.

  14. Immunisation of mice against Taenia taeniaeformis using antigens prepared from T. pisiformis and T. hydatigena eggs or oncospheres.

    Science.gov (United States)

    Rickard, M D; Rajasekariah, G R; Mitchell, G F

    1981-01-01

    Experiments were carried out to investigation the degree of immunity stimulated against Taenia taeniaeformis infection in mice by prior administration of eggs or ultrasonically disrupted oncospheres of T. pisiformis or T. hydatigena. Sonicated oncospheral antigens were given either orally or by subcutaneous injection in Freund's complete adjuvant, and eggs were given orally. Three inbred strains of mice with varying degrees of innate resistance to initial infection with T. taeniaeformis were used in the experiments. These were the moderately resistant BALB/c, moderately susceptible CBA/H, and highly susceptible C3H/He strains. It was found that BALB/c mice developed high levels of immunity when immunised with either T. pisiformis or T. hydatigena eggs, or with sonicated oncospheres administered orally or parenterally. CBA/H mice developed moderate immunity, and C3H/He mice generally did not develop a satisfactory level of resistance. the implication of these findings with respect to immunisation of outbred animals against natural infection with larval cestodes using antigen prepared from the oncospheres of heterologous parasite species is discussed.

  15. Characterisation of antibody responses in pigs induced by recombinant oncosphere antigens from Taenia solium.

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    Jayashi, César M; Gonzalez, Armando E; Castillo Neyra, Ricardo; Kyngdon, Craig T; Gauci, Charles G; Lightowlers, Marshall W

    2012-12-14

    Recombinant antigens cloned from the oncosphere life cycle stage of the cestode parasite Taenia solium (T. solium) have been proven to be effective as vaccines for protecting pigs against infections with T. solium. Previous studies have defined three different host protective oncosphere antigens, TSOL18, TSOL16 and TSOL45. In this study, we evaluated the potential for combining the antigens TSOL16 and TSOL18 as a practical vaccine. Firstly, in a laboratory trial, we compared the immunogenicity of the combined antigens (TSOL16/18) versus the immunogenicity of the antigens separately. Secondly, in a field trial, we tested the ability of the TSOL16/18 vaccine to induce detectable antibody responses in animals living under environmental stress and traditionally reared in areas where T. solium cysticercosis is endemic; and finally, we characterised the immune response of the study population. Pigs of 8-16 weeks of age were vaccinated with 200 μg each of TSOL16 and TSOL18, plus 5mg of Quil-A. Specific total IgG, IgG(1) and IgG(2) antibody responses induced by TSOL16 and TSOL18 were determined with ELISA. The immunogenicity of both antigens was retained in the combined TSOL16/18 vaccine. The combined vaccine TSOL16/18 induced detectable specific anti-TSOL18 antibody responses in 100% (113/113) and specific anti-TSOL16 in 99% (112/113) of the vaccinated animals measured at 2 weeks following the booster vaccination. From the two IgG antibody subtypes analysed we found there was stronger response to IgG(2).

  16. Protection against Taenia pisiformis larval infection induced by a recombinant oncosphere antigen vaccine.

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    Chen, L; Yang, D Y; Xie, Y; Nong, X; Huang, X; Fu, Y; Gu, X B; Wang, S X; Peng, X R; Yang, G Y

    2014-02-13

    Taenia pisiformis larvae cause significant health problems to rabbits. At present, it is not known whether the recombinant antigen from the T. pisiformis oncosphere is able to confer protective immunity against T. pisiformis larval infection. The full-length cDNA was cloned into a pET32a (+) vector, and the recombinant protein was then expressed in BL21 (DE3) cells. Vaccination with the purified rTpUbc2 coupled with QuilA was carried out in New Zealand rabbits to evaluate the immunoprotective effect against T. pisiformis infection. The full-length open reading frame of the TpUbc2 gene was 444 bp, and encoded a 16.63-kDa protein. Finally, rTpUbc2 was used to evaluate the ability to induce immunoprotective responses in rabbits. A 79.3-90.8% reduction (P 0.05). Our data support the use of rTpUbc2 as a potential candidate to develop a vaccine against T. pisiformis larvae.

  17. The highly antigenic 53/25 kDa Taenia solium protein fraction with cathepsin-L like activity is present in the oncosphere/cysticercus and induces non-protective IgG antibodies in pigs.

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    Zimic, Mirko; Pajuelo, Mónica; Gilman, Robert H; Gutiérrez, Andrés H; Rueda, Luis D; Flores, Myra; Chile, Nancy; Verástegui, Manuela; Gonzalez, Armando; García, Héctor H; Sheen, Patricia

    2012-01-15

    Cathepsin L-like proteases are secreted by several parasites including Taenia solium. The mechanism used by T. solium oncospheres to degrade and penetrate the intestine and infect the host is incompletely understood. It is assumed that intestinal degradation is driven by the proteolytic activity of enzymes secreted by the oncosphere. Blocking the proteolytic activity by an antibody response would prevent the oncosphere penetration and further infection. Serine and cysteine proteases including chymotrypsin, trypsin, elastase, and cathepsin L, are secreted by T. solium and Taenia saginata oncospheres when cultured in vitro, being potential vaccine candidates. However, the purification of a sufficient quantity of proteases secreted by oncospheres to conduct a vaccine trial is costly and lengthy. A 53/25 kDa cathepsin L-like fraction partially purified from T. solium cyst fluid was described previously as an important antigen for immunodiagnostics. In this study we found that this antigen is present in the T. solium oncosphere and is also secreted by the cysticercus. This protein fraction was tested for its ability to protect pigs against an oral challenge with T. solium oncospheres in a vaccine trial. IgG antibodies against the 53/25 kDa cathepsin L-like protein fraction were elicited in the vaccinated animals but did not confer protection.

  18. Immunolocalization of TSOL18 and TSOL45-1A, the successful protective peptides against porcine cysticercosis, in Taenia solium oncospheres

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    Maravilla Pablo

    2011-01-01

    Full Text Available Abstract Taenia solium life cycle includes humans as definitive hosts and pigs as intermediate hosts. One of the measures to stop the life cycle of this parasite is by vaccination of pigs. In experiments performed in pigs with TSOL18 and TSOL45-1A, two recombinant T. solium proteins, 99.5% and 97.0% protection was induced, respectively. The purpose of this paper was to localize these antigens in all stages of the parasite (adult worms, oncospheres and cysticerci by immunofluorescence, with the use of antibodies against TSOL18 and TSOL45-1A that were obtained from the pigs used in the vaccination experiment. Results show that TSOL18 and TSOL45-1A are expressed on the surface of T. solium oncospheres and not in tapeworms or cysticerci, indicating that they are stage-specific antigens. This, therefore, might explain the high level of protection these antigens induce against pig cysticercosis.

  19. Stage-specific immunity to Taenia taeniaeformis infection in mice. A histological study of the course of infection in mice vaccinated with either oncosphere or metacestode antigens.

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    Bøgh, H O; Lightowlers, M W; Sullivan, N D; Mitchell, G F; Rickard, M D

    1990-03-01

    The course of Taenia taeniaeformis infection in mice previously vaccinated with antigens prepared from either oncosphere (TtO) or metacestode (TtM) was followed by histological examination of livers from mice killed at various times post-infection (p.i.). Distinctly different immune responses occurred in the two groups. Very few cysts were seen at any stage of infection in TtO-vaccinated mice and most of those which were present appeared histologically similar to cysts in control mice. In TtM-vaccinated mice many cysts were present from early in infection but histologically it was apparent that most were dying from 15 days p.i. because the tegument had lost its integrity, and degranulated polymorphonuclear leucocytes were present inside the parasites. These findings support earlier suggestions that stage-specific antigens are expressed in oncospheres and metacestodes. Parasites developing normally were surrounded by a halo of alcian blue staining amorphous acellular material. This material appeared to act as a barrier to attack by host inflammatory cells, and disappearance of this layer signalled death of the parasite. The possibility that the gut acted as a barrier to delay migration of oncospheres to the liver in vaccinated mice was investigated, but no evidence for this could be found.

  20. Optimized codon usage enhances the expression and immunogenicity of DNA vaccine encoding Taenia solium oncosphere TSOL18 gene.

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    Wang, Yuan-Yuan; Chang, Xue-Lian; Tao, Zhi-Yong; Wang, Xiao-Li; Jiao, Yu-Meng; Chen, Yong; Qi, Wen-Juan; Xia, Hui; Yang, Xiao-Di; Sun, Xin; Shen, Ji-Long; Fang, Qiang

    2015-07-01

    Cysticercosis due to larval cysts of Taenia solium, is a serious public health problem affecting humans in numerous regions worldwide. The oncospheral stage-specific TSOL18 antigen is a promising candidate for an anti-cysticercosis vaccine. It has been reported that the immunogenicity of the DNA vaccine may be enhanced through codon optimization of candidate genes. The aim of the present study was to further increase the efficacy of the cysticercosis DNA vaccine; therefore, a codon optimized recombinant expression plasmid pVAX1/TSOL18 was developed in order to enhance expression and immunogenicity of TSOL18. The gene encoding TSOL18 of Taenia solium was optimized, and the resulting opt-TSOL18 gene was amplified and expressed. The results of the present study showed that the codon-optimized TSOL18 gene was successfully expressed in CHO-K1 cells, and immunized mice vaccinated with opt-TSOL18 recombinant expression plasmids demonstrated opt‑TSOL18 expression in muscle fibers, as determined by immunohistochemistry. In addition, the codon-optimized TSOL18 gene produced a significantly greater effect compared with that of TSOL18 and active spleen cells were markedly stimulated in vaccinated mice. 3H-thymidine incorporation was significantly greater in the opt-TSOL18 group compared with that of the TSOL18, pVAX and blank control groups (P<0.01). In conclusion, the eukaryotic expression vector containing the codon-optimized TSOL18 gene was successfully constructed and was confirmed to be expressed in vivo and in vitro. The expression and immunogenicity of the codon-optimized TSOL18 gene were markedly greater compared with that of the un-optimized gene. Therefore, these results may provide the basis for an optimized TSOL18 gene vaccine against cysticercosis.

  1. 链状带绦虫六钩蚴形态与猪体感染初期分布的研究%STUDY ON MORPHOLOGY OF TAENIA SOLIUM ONCOSPHERE AND EARLYSTAGE DISTRIBUTION IN PIG INFECTION

    Institute of Scientific and Technical Information of China (English)

    赵旭东; 李莹; 王昊; 高葆真; 尹光升

    2000-01-01

    本文通过链状带绦虫虫卵体外孵育和猪体感染,对六钩蚴形态和感染猪体初期的分布进行了观察。体外孵育的六钩蚴有4种不同的运动形式,可能与卵成熟情况有关;定向运动的六钩蚴有感染能力;扫描电镜下不能运动的六钩蚴外有一层单位膜包囊;六个小钩为六钩蚴的运动器官,感染宿主后10~15d开始退化消失。%Morphology of oncosphere and early stage distribution of infection in pig was studied througe in vitro incubation and imposed infection on pig. There are four motion patterns of oncosphere which may be related to degree of maturity. Those with oriented motion is of infectious oncosphere. Under scanning electronic microscope ,oncosphere without mobility is found to be wraped with a layer of membrane. The six hooks are the motion organs which sloughs after 10-15 days infectiing the host.

  2. Research progress on 18 gene of Taenia solium oncosphere%猪带绦虫六钩蚴TSO18基因研究进展

    Institute of Scientific and Technical Information of China (English)

    周必英; 陈雅棠; 李文桂

    2009-01-01

    Cysticercosis cellulosae is a severe zoonotic disease caused by the larval stage(Cysticercus cellulosae)of the helminth Taenia solium.Vaccine plays an important role in preventing and controlling the disease.TSO18 gene is an immunogen gene of Taenia solium oncosphere(TSO)stage,which is regarded as the most perspective vaccine candidate gene.This article reviews molecular biology of Taenia solium oncosphere TSO18 gene and the development of TSO18 vaccine.%猪囊尾蚴病是一种严重危害人类健康的人兽共患寄生虫病,疫苗是预防控制猪囊尾蚴病的重要手段.TSO18基因是猪带绦虫六钩蚴阶段重要的免疫原基因,被认为是最具有前途的疫苗候选基因.该文综述了猪带绦虫六钩蚴TSO18基因的分子生物学及其疫苗开发的研究进展.

  3. Cloning and Expression of HSP of Taenia Solium Oncosphere%猪带绦虫六钩蚴 HSP 的克隆和表达

    Institute of Scientific and Technical Information of China (English)

    王哲; 赵权

    2013-01-01

      The HSP gene was separately amplified from total RNA of activated Taenia solium oncosphere by RT -PCR.The PCR products were cloned into pGH vector,recombinant positive clones was sequenced after restriction enzyme digestion.The HSP gene was subcloned into pET28a expression vector,the recombinant pET28a-HSP infected into E.coliBL21.IPTG was added to induce fusion expression and the expression products was identified by SDS-PAGE and Western-blot.One fusion protein band about 35 kDa was identified by SDS -PAGE after inducible expression after inducible expression,The result would lay foundations for the mechanism of invasion of between oncosphere and host,and the design of new vaccine anti-porcine cysticercosis and taeniasis.%  提取猪带绦虫激活和未激活六钩蚴总 RNA,RT-PCR 扩增 HSP 目的基因,将目的基因与 pGH 克隆载体连接,经酶切鉴定后,将阳性重组质粒进行测序,结果扩增出激活的六钩蚴的目的片段。将目的基因亚克隆到原核表达载体 pET-28a-HSP中,并将获得的 pET28a-HSP 阳性重组子转化至宿主菌 E.coliBL21,IPTG 进行诱导表达,并对重组抗原 pET-28a-HSP 进行SDS-PAGE 和 Western-blot 检测。结果表明重组经 SDS-PAGE 分析可见一条约35 kDa 大小的融合蛋白条带的抗原,Western-blot 结果显示其能被囊虫病人阳性血清识别。这将为进一步阐明六钩蚴入侵中间宿主的机理、设计新型抗猪囊虫病和绦虫病疫苗打下基础。

  4. Evaluation of a synthetic peptide from the Taenia saginata 18kDa surface/secreted oncospheral adhesion protein for serological diagnosis of bovine cysticercosis.

    Science.gov (United States)

    Guimarães-Peixoto, Rafaella Paola Meneguete; Pinto, Paulo Sérgio Arruda; Santos, Marcus Rebouças; Polêto, Marcelo Depólo; Silva, Letícia Ferreira; Silva-Júnior, Abelardo

    2016-12-01

    Bovine cysticercosis is a zoonotic infection widely spread throughout Brazil, creating a burden on hygiene maintenance and the economy. Diagnosis of cysticercosis usually relies on post mortem inspection of carcasses in slaughterhouses. This detection method provides only low sensitivity. Recent advancements have improved the performance of serologic tests, such as ELISA, providing greater sensitivity and specificity. The objective of the current study was to identify and evaluate a synthetic peptide derived from the Taenia saginata 18kDa oncospheric surface protein for the diagnosis of bovine cysticercosis in ELISA. Test performance of the identified peptide was compared to an ELISA based on a heterologous crude Taenia crassiceps antigen (Tcra), widely used for the sero-diagnosis of bovine cysticercosis. Based on the primary sequence of an in silico structural model of the 18kDa protein, an epitope region designated EP1 was selected (46-WDTKDMAGYGVKKIEV-61). The peptide derived from this region yielded 91.6% (CI=80-96%) sensitivity and 90% (CI=82-95%) specificity when used in an ELISA, whereas the crude antigen yielded 70% (CI=56-8%) sensitivity and 82% (CI=73-89%) specificity. Thus, we conclude that EP1 has higher diagnostic potential for detecting bovine cysticercosis than the crude antigen Tcra.

  5. Proteomic analysis of the nonactivated and activated proteins of Taenia solium oncosphere stimulated by artificial intestinal fluid%体外人工肠液激活与未激活的猪带绦虫六钩蚴差异蛋白质组学比较

    Institute of Scientific and Technical Information of China (English)

    王哲; 王丹; 李巍; 蔡亚楠; 杨桂连; 赵权

    2011-01-01

    为建立一种用于比较猪带绦虫六钩蚴(Taenia solium)激活前后蛋白差异表达的二维液相色谱方法,本研究对人工肠液激活前后的六钩蚴进行一维色谱聚焦和二维反相色谱分析,以0.3pH为单位在pH7.71~pH5.31的范围内梯度分离出208个激活和197个未激活的六钩蚴蛋白.Mapping tools软件分析结果表明,六钩蚴激活前后的差异蛋白数量为77个,其中激活的六钩蚴差异蛋白44个,未激活的六钩蚴差异蛋白33个.该方法具有分辨率高、重现性好、自动化程度高的特点,为研究六钩蚴与其宿主间的寄生机制提供研究方法.%For proteomic analysis of Taenia solium oncosphere, the one-dimensional chromatofocusing and two-dimensional liquid reversion phase chromatography was used to separate and compare the difference of protein expressions in nonactivated and activated of T. solium oncospherein stimulated by artificial instestinal fluid. Total of 208 activated and 197 nonactivated oncospherein proteins were obtained by 0.3pH gradient separation between pH7.71 to pH5.31. Seventy-seven differentially proteins were identified by Mapping tools comparison, of which 44 differentially expressed proteins were found in activated and 33 in nonactivated T. solium oncospherein. The analysis method was proved to be effective, stable and high-automaticity, which has tremendous developing potentiality on the research of differential proteomic expression profile. The research work sets up a foundation for the research on the parasite mechanism of host and oncosphere.

  6. 两种MHC-DRB1单倍型哈萨克绵羊细粒棘球六钩蚴侵染期小肠消减文库的构建%Construction of Subtracted Library of Small Intestine in Kazakh Sheep with Two MHC-DRB1 Genotypes Infected by Echinococcus oncosphere

    Institute of Scientific and Technical Information of China (English)

    杜鑫立; 惠文巧; 赵博; 郭玉强; 马军德; 马世俊; 木叶沙尔·巴吐尔; 刘贤侠; 贾斌

    2012-01-01

    为了分离两种MHC-DRB1单倍型哈萨克绵羊个体在细粒棘球六钩蚴侵染期小肠组织的差异表达基因,试验在实验室前期采用PCR-RFLP方法筛选获得这两种MHC-DRB1单倍型(包虫病抗性相关的MHC-DRB1 MvaIbc-SacIIab-Hin1Iab单倍型和包虫病非抗性相关的MHC-DRB1 MvaIbb-SacIIaa-Hin1Iaa单倍型)的基础上,采用抑制性消减杂交技术构建了以非抗性相关哈萨克绵羊六钩蚴侵染期小肠cDNA为实验方(Tester),抗性相关哈萨克绵羊六钩蚴侵染期小肠cDNA为消减方(Driver)的消减文库.结果显示:以内参基因GAPDH为指标,检测文库的消减效率为215倍;从文库中随机挑选98个阳性克隆进行了PCR检测,显示插入片段的大小分布于150~1000bp.结论:消减文库的构建成功,为进一步分离和鉴定相关的差异表达基因,探讨包虫病抗性相关MHC-DRB1单倍型哈萨克绵羊抵抗六钩蚴侵染的分子作用机制奠定了研究基础.%In order to isolate the differentially expressed genes of small intestine in Kazakh sheep with two MHC-DRB1 genotypes infected by Echinococcus oncosphere ,a subtractive cDNA library was constructed by suppression subtractive hybridizatior technique, which used the cDNA of small intestine of Kazakh sheep associated with hydatidosis nonresistance and resistance as tester and driver respectively. The study was based on preliminary research that two MHC-DRB1 genotypes (MHC-DRB1 Mvalbc-SacIIab-Hinllab associated with hydatidosis resistance,and MHC-DRB1 Mvalbb-SacIIaa-HinlIaa associated with hydatidosis nonresistance) were chosen by using the PCR-RFLP technique. A housekeeping gene, GAPDH, was used to estimate the efficiency of subtractive and it was subtracted efficiently at appropriate 215 folds in the subtractive cDNA library. A total of 98 positive clones were isolated from the library. Analysis of PCR showed that plasmids in the clones contained 150-1000 bp inserts. The construction of the subtractive c

  7. 猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域相应的线性B细胞表位肽免疫原性研究%Research on immunity response about Taenia solium oncosphere TSO45-4B antigens FnⅢ structure domain linear B cells epitope peptides

    Institute of Scientific and Technical Information of China (English)

    王媛媛; 陶志勇; 杨小迪; 王小莉; 常雪莲; 陈勇; 孙新; 夏惠; 方强

    2013-01-01

    Objective: To observe the humoral immune response induced by Taenia solium oncosphere TSO45-4B antigens Fn Ⅲ structure domain linear B cells epitope peptides in mice. Methods: The two predicted B cell epitope peptides of TSO45-4B Fn Ⅲ structure domain conjugated with carrier protein of keyhole limpet hemocyanin were synthesized and used to immunize mice. The mice specific serum antibody titer to the epitope peptides synthesized was tested by ELISA. Results: The specific antibody to one of the predicted epitope peptides synthesized was found in mice serum,and the titer was 1: 1 280. Conclusions: One of the two predicted linear B cell epitope peptides of TSO45-4B FnⅢ structure domain can induce the humoral immune response in mice.%目的:观察载体蛋白偶联的TSO45-4B抗原FnⅢ结构域相应的线性B细胞表位肽诱导的体液免疫反应.方法:人工合成TSO45-4B抗原FnⅢ结构域2条预测表位肽,偶联钥孔血蓝蛋白免疫小鼠,采用ELISA法检测小鼠血清中预测表位肽特异性抗体滴度.结果:免疫小鼠血清中检测到1条预测表位肽特异性抗体,其效价达到1:1 280.结论:设计的1条TSO45-4B抗原FnⅢ结构域线性B细胞表位肽可诱导小鼠产生体液免疫反应.

  8. Prediction and identification of Taenia solium oncosphere TSO45-4B antigen FnⅢ structure domain linear B cell epitopes%猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位预测及鉴定

    Institute of Scientific and Technical Information of China (English)

    王媛媛; 王小莉; 常雪莲; 陶志勇; 夏惠; 方强

    2012-01-01

    Objective To predict and identify Taenia solium oncosphere TSO45-4B antigen FnⅢ structure domain linear B cell epitopes. Methods The B cell epitopes of TSO45-4B FnⅢ structure domain were predicted through the sequence analysis by using bioinformatics online tools and the protein space conformation was predicted by SWISS-MODEL. The peptides were synthesized according to the predicted linear epitopes. The immunoreactivity of sera of cysticercosis patients to the peptides synthesized was tested by using ELISA. Results Two linear B cell epitopes of TSO45-4B FnⅢ structure domain were predicted, and one of the predicted epitope peptides synthesized could be recognized by the sera of cysticercosis patients. Conclusion Two linear B cell epitopes of TSO45-4B Fn Ⅲ structure domain are predicted and one of them has been confirmed successfully.%目的 预测并鉴定猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位.方法 利用生物信息学在线工具分析TSO45-4B抗原FnⅢ结构域序列并预测其线性B细胞表位;采用SWISS-MODEL软件预测TSO45-4B的蛋白空间结构,并合成两条预测表位肽.采用酶联免疫吸附试验(ELISA)检测猪囊尾蚴病人血清与两条预测表位肽的免疫反应性.结果 获得2个TSO45-4B抗原FnⅢ结构域线性B细胞预测表位,其中1条预测表位合成肽可为猪囊尾蚴病患者血清识别.结论 成功预测并鉴定了猪带绦虫六钩蚴TSO45-4B抗原FnⅢ结构域线性B细胞表位.

  9. From stillness to motion: 80 years after the first description of Taenia solium oncosphere hatching

    OpenAIRE

    Mendlovic, Fela; Garza-Rodríguez, Adriana; Carrillo-Farga, Joaquin; González-Domínguez, Fernando; Maravilla, Pablo; Flisser,Ana

    2014-01-01

    Background Human neurocysticercosis (NCC) is a considered public health problem in many underdeveloped and developing countries. Because of the enormous increase in international tourism and migration, NCC nowadays is also found in some developed countries. Our group was the first to demonstrate that tapeworm carriers in the household are the main risk factor for acquiring cysticercosis in humans and pigs, since the disease results from the ingestion of microscopic tapeworm eggs. Findings We ...

  10. Immune responses to a recombinant attenuated Salmonella typhimurium strain expressing a Taenia solium oncosphere antigen TSOL18.

    Science.gov (United States)

    Ding, Juntao; Zheng, Yadong; Wang, Ying; Dou, Yongxi; Chen, Xiaoyu; Zhu, Xueliang; Wang, Shuai; Zhang, Shaohua; Liu, Zhenyong; Hou, Junling; Zhai, Junjun; Yan, Hongbin; Luo, Xuenong; Cai, Xuepeng

    2013-01-01

    A tapeworm, Taenia solium, remains a great threat to human health, particularly in developing countries. The life cycle of T. solium is thought to be terminated via vaccination of intermediate hosts. In this study, we constructed a recombinant attenuated Salmonella typhimurium live vaccine strain χ4558 expressing a TSOL18 antigen. SDS-PAGE and Western blot confirmed the expression of the interest protein and its antigenic property. The recombinant strain stably propagated in vitro, of which the growth was not reversely influenced by TSOL18 protein expressed. It was also shown that mice survived 10(12) CFU of S. typhimurium χ4558, while all mice infected with 10(7) CFU of the wild-type died within five days. The mouse experiment indicated that vaccine strain χ4558 induced a high titer of specific antibody for a long time. In contrast to the controls, the vaccinated mice had an obvious augment of CD4(+) and CD8(+) T lymphocytes and the percentage of helper CD4(+)/CD8(+) T lymphocytes was significantly increased (psolium.

  11. 猪带绦虫六钩蚴的体外培养%Cultivation of Oncospheres of Taenia Solium in vitro

    Institute of Scientific and Technical Information of China (English)

    刘永杰; 郝艳红; 李庆章

    2002-01-01

    采用12种培养体系培养猪带绦虫六钩蚴,结果发现单层细胞且无气相存在的培养体系效果较好,促使大部分六钩蚴进入了六钩蚴后期发育,且虫体可延长存活至16d.

  12. Eosinophil chemotactic factors from cysticercoids of Hymenolepis nana.

    Science.gov (United States)

    Niwa, A; Asano, K; Ito, A

    1998-09-01

    A comparative study of eosinophil chemotactic factors was carried out using cysticercoids and oncospheres of Hymenolepis nana. Cysticercoids showed twice the chemotactic activity for eosinophils than the oncospheres. Eosinophilia induced by oncospheres and cysticercoids observed in secondary and primary infections, respectively, were discussed from the view point of the immunobiology of this parasite.

  13. The Cloning & Expression of Immunogen Gene of Oncosphere of Taenia solium and Structural Prediction of Protein%猪带绦虫六钩蚴免疫原基因的克隆、表达与结构预测

    Institute of Scientific and Technical Information of China (English)

    景志忠; 窦永喜; 蒙学莲; 吴国华; 才学鹏

    2005-01-01

    从猪带绦虫六钩蚴cDNA表达文库中筛选、克隆的Ts01基因,设计表达性引物,亚克隆到pGEX-4T-1表达载体,构建了pGEX-GST-Ts01的融合表达重组载体,转化BL21寄主菌和IPTG诱导表达后,经SDS-PAGE和Western蛋白分析,表明成功地高效表达了约40 000左右的融合蛋白质,与预测的相对分子质量大小一致,表达量达40%左右.表达产物具有免疫学活性,而且呈可溶性,未形成包涵体,这与用蛋白质软件分析的Ts01编码蛋白水溶性相一致.

  14. TSO45W genetically engineering vaccine against Taenia solium oncosphere%猪带绦虫六钩蚴TSO45W基因工程疫苗研究进展

    Institute of Scientific and Technical Information of China (English)

    周必英; 陈雅棠; 李文桂

    2009-01-01

    囊虫病是一种危害严重的人兽共患寄生虫病.研制有保护性作用的疫苗将是控制和消灭该病的有效方法,猪带绦虫保护性抗原的研究是猪囊虫病免疫的基础.45W蛋白是猪带绦虫六钩蚴时期的重要抗原,但天然45W抗原来源有限,限制了其应用,而基因工程重组抗原的应用可解决质量控制和抗原来源的问题.本文就近年来国内外对猪带绦虫六钩蚴TSO45W基因工程疫苗的研究进展作一综述.

  15. Hymenolepis nana: the fine structure of the embryonic envelopes.

    Science.gov (United States)

    Fairweather, I; Threadgold, L T

    1981-06-01

    The fine structure of the envelopes surrounding hatched and unhatched oncospheres of Hymenolepis nana has been investigated by transmission and scanning electron microscopy (SEM), together with light microscope histochemical observations of JB-4 embedded material. The oncosphere is surrounded by 3 layers--the capsule, the outer envelope and the inner envelope, the latter giving rise to the embryophore and the 'oncospheral membrane'. An additional layer--the polar filament layer--lies between the 'oncospheral membrane' and the oncosphere. Shell material is deposited on the capsule as a thin layer. It is secreted by the outer envelope, which degenerates once shell formation is complete. The uterus may also contribute to shell formation. The embryophore forms a thin incomplete and peripheral layer within the inner envelope. In the basal region of this envelope, partial development of an 'oncospheral membrane' takes place, but it does not become detached as a separate layer. The polar filaments, which are characteristic of the oncosphere of H. nana, are derived from the epithelial covering of the oncosphere itself, which delaminates to form a separate polar filament layer. The filaments arise from knob-like projections at opposite poles of this layer. The design of the embryonic envelopes in H. nana show a number of modifications from the basic cyclophyllidean pattern, and these can be related to the demands of its 'direct' life-cycle.

  16. The immuno-protective effect of UV-attenuated Taenia asiatica oncospheres in domestic pigs%紫外线致弱亚洲带绦虫六钩蚴疫苗对乳猪的免疫保护作用

    Institute of Scientific and Technical Information of China (English)

    杨鹏; 张万; 党荣敏; 谢洪书; 尹丙娇

    2014-01-01

    目的 观察接种紫外线(UV)致弱亚洲带绦虫六钩蚴疫苗对乳猪的免疫保护作用. 方法 以UV致弱六钩蚴疫苗经耳缘静脉免疫乳猪,采用ELISA法检测乳猪免疫前后血清特异性IgG,以及脾淋巴细胞体外诱生INF-γ和IL-4水平,并于免疫后35d进行虫卵攻击感染,在感染第15d和45 d比较免疫组和感染对照组囊尾蚴数量变化及发育情况. 结果 乳猪接种UV致弱六钩蚴第10d,血清特异性IgG含量开始上升,第35 d为(34.4±5.02)mg/ml,与免疫前(13.7±4.37)mg/ml比较差异有统计学意义(t=9.312,P<0.05);脾淋巴细胞经体外培养24 h后,免疫组上清IL-4为(39.65±15.3)mg/ml,与正常对照组为(15.8±7.5) mg/ml比较差异有统计学意义(F=10.45,P<0.05),INF-γ含量与正常对照组比较差异无统计学意义(F=2.456,P>0.05);免疫组脾淋巴细胞经ConA刺激体外培养24 h,上清IL-4含量为(156.94±11.81)mg/ml,正常对照组为(80.6±13.5)mg/ml差异有统计学意义(F=32.82,P<0.05),INF-γ含量差异无统计学意义(F=7.17,P>0.05).虫卵攻击感染第15d,免疫组囊尾蚴数总数减少,退化或钙化囊尾蚴数增多,成熟囊尾蚴数减少,第45 d时免疫组未见成熟囊尾蚴. 结论 UV致弱亚洲带绦虫六钩蚴疫苗可诱导乳猪产生较高水平免疫保护力.

  17. 猪带绦虫六钩蚴cDNA文库的构建及免疫原基因的筛选与克隆%The Construction and Screening of cDNA Expression Library of Oncosphere of Taenia solium and cloning of Immunogen Gene

    Institute of Scientific and Technical Information of China (English)

    景志忠; 郭爱疆; 海岗; 宗瑞谦; 才学鹏

    2005-01-01

    研究避开庞大的猪带绦虫基因组DNA,以构建六钩蚴发育阶段的cDNA表达文库为策略,利用pSPORT1质粒表达载体首次成功构建了表达文库.经库容量、重组率和代表性测定,库容量达5.0×106,重组率100%,用特异性引物能扩增出六钩蚴发育阶段10 ku基因、18 ku基因和45W基因家族的A型、B型、C型转录本,说明文库质量高,代表性强.应用快速筛选质粒表达文库和克隆免疫原基因的技术,成功地筛选和克隆到TsO1基因,其完整阅读框架(ORF)为393 bp.将其登录到GenBank(AY327451),经BLAST分析,证实是猪带绦虫六钩蚴发育阶段的1个新免疫原基因.

  18. IMMUNIZATION PROTECTION OF ANTI-IDIOTYPE ANTIBODIES TO ONCOSPHERE OF TAENIA SOLIUM AGAINST TAENIA TAENIASIS IN SWINE%抗猪带绦虫六钩蚴独特型抗体疫苗对猪体免疫保护作用的研究

    Institute of Scientific and Technical Information of China (English)

    王洪法; 张红花; 李怀菊; 赵长磊; 陈锡欣; 岳继娥; 杨淑芳

    2004-01-01

    目的本研究在证实猪带绦虫六钩蚴抗原具有很高的免疫保护性的基础上,探讨六钩蚴抗独特型抗体作为六钩蚴抗原替代物对猪体的保护作用,为研制猪体囊虫疫苗提供理论基础. 方法用六钩蚴粗制抗原免疫家兔,制备兔抗六钩蚴抗体(Ab1),再用Ab1免疫昆明小白鼠,制备抗独特型抗体(Ab2),免疫猪体,以3节猪带绦虫孕卵节片攻击感染,90 d后剖杀,观察感染情况. 结果 5头试验猪只有1头在膈肌发现1个囊虫,而2头阳性对照猪均被感染,各检查部位囊虫数平均为4.5个/100 g和3.2个/100 g. 结论抗猪带绦虫六钩蚴独特性抗体Ab2对猪体有较强的免疫保护作用.

  19. Vaccination against Taenia taeniaeformis infection in rats using a recombinant protein and preliminary analysis of the induced antibody response.

    Science.gov (United States)

    Ito, A; Bøgh, H O; Lightowlers, M W; Mitchell, G F; Takami, T; Kamiya, M; Onitake, K; Rickard, M D

    1991-01-01

    Primary screening of a cDNA expression library of Taenia taeniaeformis oncospheres in lambda gt11 bacteriophage was carried out using rabbit anti-T, taeniaeformis oncosphere serum affinity-purified from oncosphere pellets. From approximately 1.6 x 10(5) plaques, 21 single clones that were positive with the affinity-purified antibodies were isolated. Sibling analysis revealed that 17 clones out of the 21 could be assigned to five different antigen families. Only family 1 was strongly recognized by a serum prepared in a rabbit against a partially purified host-protective oncosphere antigen fraction. The fragments of lambda DNA were inserted into a pGEX plasmid vector that encodes glutathione S-transferase (GST) of Schistosoma japonicum. Clones designated TtO-18, -49.53 (family 1), 46 (family 2), 15 (family 3), 40 (family 4) and 66 (family 5) were established as subclones in pGEX-1 plasmid vectors which produced GST fusion proteins. All GST fusion proteins were soluble and recognized by anti-GST and anti-TtO sera. Three vaccination experiments with these fusion proteins using specific-pathogen-free Wistar rats revealed that all three fusion proteins of family 1 were exclusively effective against T. taeniaeformis oncosphere challenge with approximately 95% and 91% reductions in cystic metacestode and total metacestode recoveries, respectively. Rats vaccinated with fusion proteins of family 1 produced antibodies which reacted with a 21-kDa oncosphere antigen component which appeared to be a major oncosphere stage-specific antigen.

  20. Changes in surface antigens of Hymenolepis nana during differentiation and maturation in mice.

    Science.gov (United States)

    Ito, A; Onitake, K

    1987-06-01

    The surface antigens of oncosphere, cysticercoid, adult scolex and adult strobila (other than scolex) of Hymenolepis nana differ critically from one another. When the oncosphere of H. nana undergoes differentiation and development into the mature tapeworm, the infected mouse first produces anti-oncosphere antibody, followed by anti-cysticercoid, anti-adult scolex and finally anti-strobila (other than scolex region) antibodies of IgG, IgM and IgA isotypes as detected by indirect immunofluorescent antibody test. The parasite changed its surface antigens throughout its differentiation and maturation, and all developmental stages were recognized by the infected mouse host. However, there appeared no further changes in surface antigens during aging after maturation. The antibody responses were always delayed compared with the differentiation and maturation of the parasite.

  1. Cystic metacestodes of a rat-adapted Taenia taeniaeformis established in the peritoneal cavity of scid and nude mice.

    Science.gov (United States)

    Ito, A; Ma, L; Sato, Y

    1997-08-01

    In vitro-hatched (but not activated) oncospheres of a rat-adapted strain of Taenia taeniaeformis intraperitoneally inoculated into severe combined immunodeficiency (scid), congenitally athymic (nude) and immunocompetent (normal) female BALB/c mice developed into cystic metacestodes in the peritoneal cavity (but not in the liver) of scid and nude mice exclusively. This suggests that cystic metacestodes of this parasite, usually harboured in the liver only, can establish in scid and nude mice provided that the oncospheres are inoculated into the peritoneal cavity. Immunodeficient mice, especially scid mice, may be a good experimental animal model for the intermediate host of any taeniid species, of human, domestic- or wild-animal origin.

  2. Delivery of Echinococcus granulosus antigen EG95 to mice and sheep using recombinant vaccinia virus.

    Science.gov (United States)

    Dutton, S; Fleming, S B; Ueda, N; Heath, D D; Hibma, M H; Mercer, A A

    2012-06-01

    The tapeworm Echinococcus granulosus is the causative agent of hydatid disease and affects sheep, cattle, dogs and humans worldwide. It has a two-stage life cycle existing as worms in the gut of infected dogs (definitive host) and as cysts in herbivores and humans (intermediate host). The disease is debilitating and can be life threatening where the cysts interfere with organ function. Interruption of the hydatid life cycle in the intermediate host by vaccination may be a way to control the disease, and a protective oncosphere antigen EG95 has been shown to protect animals against challenge with E. granulosus eggs. We explored the use of recombinant vaccinia virus as a delivery vehicle for EG95. Mice and sheep were immunized with the recombinant vector, and the result monitored at the circulating antibody level. In addition, sera from immunized mice were assayed for the ability to kill E. granulosus oncospheres in vitro. Mice immunized once intranasally developed effective oncosphere-killing antibody by day 42 post-infection. Antibody responses and oncosphere killing were correlated and were significantly enhanced by boosting mice with either EG95 protein or recombinant vector. Sheep antibody responses to the recombinant vector or to EG95 protein mirrored those in mice.

  3. Podocalyxin-like protein is expressed in glioblastoma multiforme stem-like cells and is associated with poor outcome.

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    Zev A Binder

    Full Text Available Glioblastoma multiforme (GBM is the most common primary malignant adult brain tumor and is associated with poor survival. Recently, stem-like cell populations have been identified in numerous malignancies including GBM. To identify genes whose expression is changed with differentiation, we compared transcript profiles from a GBM oncosphere line before and after differentiation. Bioinformatic analysis of the gene expression profiles identified podocalyxin-like protein (PODXL, a protein highly expressed in human embryonic stem cells, as a potential marker of undifferentiated GBM stem-like cells. The loss of PODXL expression upon differentiation of GBM stem-like cell lines was confirmed by quantitative real-time PCR and flow cytometry. Analytical flow cytometry of numerous GBM oncosphere lines demonstrated PODXL expression in all lines examined. Knockdown studies and flow cytometric cell sorting experiments demonstrated that PODXL is involved in GBM stem-like cell proliferation and oncosphere formation. Compared to PODXL-negative cells, PODXL-positive cells had increased expression of the progenitor/stem cell markers Musashi1, SOX2, and BMI1. Finally, PODXL expression directly correlated with increasing glioma grade and was a marker for poor outcome in patients with GBM. In summary, we have demonstrated that PODXL is expressed in GBM stem-like cells and is involved in cell proliferation and oncosphere formation. Moreover, high PODXL expression correlates with increasing glioma grade and decreased overall survival in patients with GBM.

  4. First ultrastructural data on the human tapeworm Taenia asiatica eggs by scanning and transmission electron microscopy (SEM, TEM).

    Science.gov (United States)

    Galán-Puchades, M Teresa; Yang, Yichao; Marcilla, Antonio; Choe, Seongjun; Park, Hansol; Osuna, Antonio; Eom, Keeseon S

    2016-09-01

    Humans are definitive hosts of three species of the Taenia genus, namely Taenia solium, Taenia saginata and Taenia asiatica. The relative novelty of the latter explains the lack of knowledge concerning certain relevant aspects related to this parasite, such as its definite geographical distribution and whether its eggs can infect humans or not. So far, only the eggs of T. solium are known to be infective for humans, producing cysticercosis. Although eggs contain the infective stage, the oncosphere, there is a lack of research on the ultrastructure of eggs of human taeniids. We show, for the first time, the ultrastructure of eggs of T. asiatica by means of SEM and TEM analyses. We detected all the envelopes, namely the egg shell, vitelline layer, outer embryophoric membrane, embryophore, granular layer, basal membrane, oncospheral membrane and oncospheral tegument. Hooks surrounded by myofibrils and glycogen-like particles, the two types of secretory granules of the penetration glands, as well as several nuclei and mitochondria were also revealed in the oncospheres. In addition to the already known structures in eggs from other Taenia species, the presence of two types of small vesicles is described herein, possibly corresponding to exosomes and ectosomes because of their shape and size, which could participate in the host/parasite intercellular communication.

  5. Images in Clinical Medicine. Taenia saginata Infestation.

    Science.gov (United States)

    Li, Jian; Guo, Eping

    2016-01-21

    A 38-year-old man presented with worsening abdominal pain, vomiting, anorexia, generalized weakness, and weight loss that had begun 3 days earlier. He had a history of eating raw beef. Examination of stool showed an embryonated egg containing an oncosphere.

  6. Matrix metalloproteinase-10 is required for lung cancer stem cell maintenance, tumor initiation and metastatic potential.

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    Verline Justilien

    Full Text Available Matrix metalloproteinases (Mmps stimulate tumor invasion and metastasis by degrading the extracellular matrix. Here we reveal an unexpected role for Mmp10 (stromelysin 2 in the maintenance and tumorigenicity of mouse lung cancer stem-like cells (CSC. Mmp10 is highly expressed in oncosphere cultures enriched in CSCs and RNAi-mediated knockdown of Mmp10 leads to a loss of stem cell marker gene expression and inhibition of oncosphere growth, clonal expansion, and transformed growth in vitro. Interestingly, clonal expansion of Mmp10 deficient oncospheres can be restored by addition of exogenous Mmp10 protein to the culture medium, demonstrating a direct role for Mmp10 in the proliferation of these cells. Oncospheres exhibit enhanced tumor-initiating and metastatic activity when injected orthotopically into syngeneic mice, whereas Mmp10-deficient cultures show a severe defect in tumor initiation. Conversely, oncospheres implanted into syngeneic non-transgenic or Mmp10(-/- mice show no significant difference in tumor initiation, growth or metastasis, demonstrating the importance of Mmp10 produced by cancer cells rather than the tumor microenvironment in lung tumor initiation and maintenance. Analysis of gene expression data from human cancers reveals a strong positive correlation between tumor Mmp10 expression and metastatic behavior in many human tumor types. Thus, Mmp10 is required for maintenance of a highly tumorigenic, cancer-initiating, metastatic stem-like cell population in lung cancer. Our data demonstrate for the first time that Mmp10 is a critical lung cancer stem cell gene and novel therapeutic target for lung cancer stem cells.

  7. In Vitro Study of Taenia solium Postoncospheral Form.

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    Nancy Chile

    2016-02-01

    Full Text Available The transitional period between the oncosphere and the cysticercus of Taenia solium is the postoncospheral (PO form, which has not yet been completely characterized. The aim of this work was to standardize a method to obtain T. solium PO forms by in vitro cultivation. We studied the morphology of the PO form and compared the expression of antigenic proteins among the PO form, oncosphere, and cysticerci stages.T. solium activated oncospheres were co-cultured with ten cell lines to obtain PO forms, which we studied at three stages of development--days 15, 30, and 60. A high percentage (32% of PO forms was obtained using HCT-8 cells in comparison to the other cell lines. The morphology was observed by bright field, scanning, and transmission electron microscopy. Morphology of the PO form changed over time, with the six hooks commonly seen in the oncosphere stage disappearing in the PO forms, and vesicles and microtriches observed in the tegument. The PO forms grew as they aged, reaching a diameter of 2.5 mm at 60 days of culture. 15-30 day PO forms developed into mature cysticerci when inoculated into rats. Antigenic proteins expressed in the PO forms are also expressed by the oncosphere and cysticerci stages, with more cysticerci antigenic proteins expressed as the PO forms ages.This is the first report of an in vitro production method of T. solium PO forms. The changes observed in protein expression may be useful in identifying new targets for vaccine development. In vitro culture of PO form will aid in understanding the host-parasite relationship, since the structural changes of the developing PO forms may reflect the parasite's immunoprotective mechanisms. A wider application of this method could significantly reduce the use of animals, and thus the costs and time required for further experimental investigations.

  8. Effect of heat treatment on viability of Taenia hydatigena eggs.

    Science.gov (United States)

    Buttar, Birpal S; Nelson, Mark L; Busboom, Jan R; Hancock, Dale D; Walsh, Douglas B; Jasmer, Douglas P

    2013-04-01

    Effects of heat treatments on activation and infectivity of Taenia hydatigena eggs were assessed. Eggs containing oncospheres were used for in vitro and in vivo studies to determine the response to 5min of heat treatment, ranging from room temperature (22°C) to 60°C. The study demonstrated 99.47% and 100% reduction in oncosphere activation or infectivity after 5min of heat treatment at 60°C and 57.38°C under in vitro and in vivo conditions, respectively. Similar results between the two approaches indicted the appropriateness of the in vitro methods to identify oncosphericidal treatments of practical significance. Similar heat treatments may also be effective against Taenia saginata and help to reduce occurrence of beef cysticercosis.

  9. Vaccination of mice against Taenia taeniaeformis using antigen fractions partitioned with Triton X-114.

    Science.gov (United States)

    Schnieder, T; Bøgh, H O; Lightowlers, M W; Rickard, M D

    1996-01-01

    Taenia taeniaeformis oncosphere and metacestode antigens were fractioned using Triton X-114 into insoluble, aqueous and detergent rich fractions. These fractions were analysed in SDS-PAGE and immunoblots and used in vaccination trials against infection with T. taeniaeformis in mice. Qualitative differences were apparent in the spectrum of antigens partitioning into the different detergent phases but host-prospective antigens were present in all three fractions. The presence of individual antigenic components in the phases did not correlate with the degree of protection afforded by these fractions in the vaccination trials. Host protective immunogenicity of T. taeniaeformis oncosphere and metacestode extracts may be due to multiple protective antigens which partition into the different Triton X-114 fractions.

  10. Taenia solium: Development of an Experimental Model of Porcine Neurocysticercosis.

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    Agnès Fleury

    Full Text Available Human neurocysticercosis (NC is caused by the establishment of Taenia solium larvae in the central nervous system. NC is a severe disease still affecting the population in developing countries of Latin America, Asia, and Africa. While great improvements have been made on NC diagnosis, treatment, and prevention, the management of patients affected by extraparenchymal parasites remains a challenge. The development of a T. solium NC experimental model in pigs that will allow the evaluation of new therapeutic alternatives is herein presented. Activated oncospheres (either 500 or 1000 were surgically implanted in the cerebral subarachnoid space of piglets. The clinical status and the level of serum antibodies in the animals were evaluated for a 4-month period after implantation. The animals were sacrificed, cysticerci were counted during necropsy, and both the macroscopic and microscopic characteristics of cysts were described. Based on the number of established cysticerci, infection efficiency ranged from 3.6% (1000 oncospheres to 5.4% (500 oncospheres. Most parasites were caseous or calcified (38/63, 60.3% and were surrounded by an exacerbated inflammatory response with lymphocyte infiltration and increased inflammatory markers. The infection elicited specific antibodies but no neurological signs. This novel experimental model of NC provides a useful tool to evaluate new cysticidal and anti-inflammatory approaches and it should improve the management of severe NC patients, refractory to the current treatments.

  11. Enhancement of intestinal eosinophilia during Hymenolepis nana infection in mice.

    Science.gov (United States)

    Niwa, A; Miyazato, T

    1996-03-01

    The ability of Hymenolepis nana oncosphere extract to induce eosinophil chemotactic response was examined in vitro and in vivo. The extract showed a chemotactic activity specific for eosinophils but not for neutrophils. Partially purified eosinophil chemotactic factors (ECFs) from the oncosphere extract showed apparent molecular mass from 5.5 to 9.6kDa and 30 to 40kDa. These were resistant to heating and proteinase K digestion but sensitive to periodate oxidation. Peritoneal injection of the crude extract or partially purified ECFs to mice resulted in a preferential eosinophil infiltration. The chemotactic activity for eosinophils was not separable from the adhesion molecule expression or oxygen radical-inducing activity by means of chromatography or chemical treatments. Furthermore, histological examination demonstrated a marked tissue eosinophilia around H. nana larvae in the intestinal lamina propria of both humoral and cell-mediated immunodeficiency mice. The present findings suggest that H. nana oncosphere-derived molecules facilitate in vivo the intestinal eosinophilia during the infection.

  12. Somatic retrotransposition is infrequent in glioblastomas.

    Science.gov (United States)

    Achanta, Pragathi; Steranka, Jared P; Tang, Zuojian; Rodić, Nemanja; Sharma, Reema; Yang, Wan Rou; Ma, Sisi; Grivainis, Mark; Huang, Cheng Ran Lisa; Schneider, Anna M; Gallia, Gary L; Riggins, Gregory J; Quinones-Hinojosa, Alfredo; Fenyö, David; Boeke, Jef D; Burns, Kathleen H

    2016-01-01

    Gliomas are the most common primary brain tumors in adults. We sought to understand the roles of endogenous transposable elements in these malignancies by identifying evidence of somatic retrotransposition in glioblastomas (GBM). We performed transposon insertion profiling of the active subfamily of Long INterspersed Element-1 (LINE-1) elements by deep sequencing (TIPseq) on genomic DNA of low passage oncosphere cell lines derived from 7 primary GBM biopsies, 3 secondary GBM tissue samples, and matched normal intravenous blood samples from the same individuals. We found and PCR validated one somatically acquired tumor-specific insertion in a case of secondary GBM. No LINE-1 insertions present in primary GBM oncosphere cultures were missing from corresponding blood samples. However, several copies of the element (11) were found in genomic DNA from blood and not in the oncosphere cultures. SNP 6.0 microarray analysis revealed deletions or loss of heterozygosity in the tumor genomes over the intervals corresponding to these LINE-1 insertions. These findings indicate that LINE-1 retrotransposon can act as an infrequent insertional mutagen in secondary GBM, but that retrotransposition is uncommon in these central nervous system tumors as compared to other neoplasias.

  13. Taenia solium: Development of an Experimental Model of Porcine Neurocysticercosis.

    Science.gov (United States)

    Fleury, Agnès; Trejo, Armando; Cisneros, Humberto; García-Navarrete, Roberto; Villalobos, Nelly; Hernández, Marisela; Villeda Hernández, Juana; Hernández, Beatriz; Rosas, Gabriela; Bobes, Raul J; de Aluja, Aline S; Sciutto, Edda; Fragoso, Gladis

    2015-01-01

    Human neurocysticercosis (NC) is caused by the establishment of Taenia solium larvae in the central nervous system. NC is a severe disease still affecting the population in developing countries of Latin America, Asia, and Africa. While great improvements have been made on NC diagnosis, treatment, and prevention, the management of patients affected by extraparenchymal parasites remains a challenge. The development of a T. solium NC experimental model in pigs that will allow the evaluation of new therapeutic alternatives is herein presented. Activated oncospheres (either 500 or 1000) were surgically implanted in the cerebral subarachnoid space of piglets. The clinical status and the level of serum antibodies in the animals were evaluated for a 4-month period after implantation. The animals were sacrificed, cysticerci were counted during necropsy, and both the macroscopic and microscopic characteristics of cysts were described. Based on the number of established cysticerci, infection efficiency ranged from 3.6% (1000 oncospheres) to 5.4% (500 oncospheres). Most parasites were caseous or calcified (38/63, 60.3%) and were surrounded by an exacerbated inflammatory response with lymphocyte infiltration and increased inflammatory markers. The infection elicited specific antibodies but no neurological signs. This novel experimental model of NC provides a useful tool to evaluate new cysticidal and anti-inflammatory approaches and it should improve the management of severe NC patients, refractory to the current treatments.

  14. Taenia solium: Development of an Experimental Model of Porcine Neurocysticercosis

    Science.gov (United States)

    Fleury, Agnès; Trejo, Armando; Cisneros, Humberto; García-Navarrete, Roberto; Villalobos, Nelly; Hernández, Marisela; Villeda Hernández, Juana; Hernández, Beatriz; Rosas, Gabriela; Bobes, Raul J.; S. de Aluja, Aline; Sciutto, Edda; Fragoso, Gladis

    2015-01-01

    Human neurocysticercosis (NC) is caused by the establishment of Taenia solium larvae in the central nervous system. NC is a severe disease still affecting the population in developing countries of Latin America, Asia, and Africa. While great improvements have been made on NC diagnosis, treatment, and prevention, the management of patients affected by extraparenchymal parasites remains a challenge. The development of a T. solium NC experimental model in pigs that will allow the evaluation of new therapeutic alternatives is herein presented. Activated oncospheres (either 500 or 1000) were surgically implanted in the cerebral subarachnoid space of piglets. The clinical status and the level of serum antibodies in the animals were evaluated for a 4-month period after implantation. The animals were sacrificed, cysticerci were counted during necropsy, and both the macroscopic and microscopic characteristics of cysts were described. Based on the number of established cysticerci, infection efficiency ranged from 3.6% (1000 oncospheres) to 5.4% (500 oncospheres). Most parasites were caseous or calcified (38/63, 60.3%) and were surrounded by an exacerbated inflammatory response with lymphocyte infiltration and increased inflammatory markers. The infection elicited specific antibodies but no neurological signs. This novel experimental model of NC provides a useful tool to evaluate new cysticidal and anti-inflammatory approaches and it should improve the management of severe NC patients, refractory to the current treatments. PMID:26252878

  15. Studies on stage-specific immunity against Taenia taeniaeformis metacestodes in mice.

    Science.gov (United States)

    Bøgh, H O; Rickard, M D; Lightowlers, M W

    1988-05-01

    The possible existence of stage-specific immune responses to Taenia taeniaeformis infection was investigated in C3H/He mice vaccinated with antigens prepared from either the oncosphere or metacestode stages. Mice were immunized twice, 2 weeks apart, with antigen in Freund's complete adjuvant. Two weeks after the second immunization they were challenged with 250 T. taeniaeformis eggs and killed day 0, 5, 10, 15, 20, 25, 30, 45 and 60 after infection. Gross examination of the livers revealed marked differences between oncosphere (TtO) and metacestode (TtM) vaccinated mice. Very few metacestodes were found in the first group but most of those that evaded the initial host attack developed like the cysts found in the control group. In contrast, many degenerating metacestodes were found in the TtM vaccinated group. In a subsequent experiment groups of mice were vaccinated with varying doses of either TtO or TtM to determine whether the qualitative differences observed above were due to antigen dose effects. However, varying antigen doses gave the same results. These data show that vaccination with oncospheres generates an immune response capable of killing invading larvae soon after infection whereas vaccination with TtM results in larvae being killed at a later stage, suggesting that there are stage-specific, host-protective antigens.

  16. Gastric hyperplasia and parietal cell loss in Taenia taeniaeformis inoculated immunodeficient mice.

    Science.gov (United States)

    Lagapa, Jose Trinipil; Konno, Kenjiro; Oku, Yuzaburo; Nonaka, Nariaki; Ito, Mamoru; Kamiya, Masao

    2002-03-01

    Immunodeficient mice were studied to determine their suitability as models in investigating the role of Taenia taeniaeformis larval products in the development of gastric hyperplasia. Recombinant active gene 2 (RAG2)-deficient and severe combined immune-deficient (SCID) mice were studied as candidate animal models. RAG2-deficient mice inoculated orally with T. taeniaeformis eggs developed gastric hyperplasia with alcian blue-periodic acid-Schiff-positive cell proliferation similar to those of rats. SCID mice inoculated with different doses and routes of T. taeniaeformis in vitro-hatched oncospheres and those orally inoculated with eggs resulted also in different degrees of gastric hyperplasia. Influence of inoculation forms of parasite, doses and routes of inoculation on initiation of hyperplastic gastropathy was suggested to be dependent on number and size of developed larvae. Both RAG2-deficient and SCID mice with hyperplastic mucosa were observed with significant loss of parietal cells. Apparent decrease in parietal cell number was observed in SCID mice at 2 weeks after intraperitoneal inoculation with oncospheres before hyperplastic lesions developed. Earliest occurrence of gastric hyperplasia in SCID mice was observed at 3 weeks after oral inoculation of in vitro-hatched oncospheres, sooner than orally inoculated rats. The results suggested that these immunodeficient mice could be used as animal models to study factors involved in T. taeniaeformis-induced gastric mucous cell hyperplasia.

  17. In vitro viability test for the eggs of Echinococcus granulosus: a rapid method.

    Science.gov (United States)

    Moazeni, Mohammad; Rakhshandehroo, Ehsan

    2012-02-01

    In this study an attempt was made to develop an efficient, rapid, simple, and reproducible method for the in vitro viability test of Echinococcus granulosus eggs. The eggs were obtained from an experimentally infected dog and kept at 4°C until use. To prepare the dead or damaged eggs, the eggs were heated in hot water (69-72°C for 10 min), preserved in 70% ethyl alcohol (16 days) or exposed to direct sunlight (18 h). Sodium hypochlorite (0.5-0.7%) was used for the hatching process, and the hatched oncospheres were stained with 0.1% eosin for the viability test. With 0.5% sodium hypochlorite, the hatching rates for viable eggs and eggs killed or damaged by heat (69°C), 70% ethyl alcohol, and direct sunlight were 96%, 97.5%, 91.5%, and 94.6% respectively and there was no significant difference between the hatching rate for viable and dead or damaged eggs (p > 0.05). After staining with 0.1% eosin, the rates of the viable oncospheres hatched from viable eggs and the eggs killed or damaged by heat (69°C), 70% ethyl alcohol, and direct sunlight were 97.5% 3.6%, 7%, and 10.5%, respectively. The difference between the rates of viable oncospheres hatched from viable and dead or damaged eggs was extremely significant (P < 0.0001). With 0.7% sodium hypochlorite, the hatching rates for viable and dead eggs (killed by 72°C for 10 min) were 99.1% and 99.9%, respectively. In this condition, the rate of viable oncospheres was an average of 98.5% for viable eggs and 0.0% for dead ones. The results of this study showed that hatching of eggs by 0.7% sodium hypochlorite and staining of hatched oncospheres by 0.1% eosin are practical methods for the differentiation of viable and nonviable (dead) eggs of Echinococcus granulosus.

  18. Novel Rat Model for Neurocysticercosis Using Taenia solium

    Science.gov (United States)

    Verastegui, Manuela R.; Mejia, Alan; Clark, Taryn; Gavidia, Cesar M.; Mamani, Javier; Ccopa, Fredy; Angulo, Noelia; Chile, Nancy; Carmen, Rogger; Medina, Roxana; García, Hector H.; Rodriguez, Silvia; Ortega, Ynes; Gilman, Robert H.

    2016-01-01

    Neurocysticercosis is caused by Taenia solium infecting the central nervous system and is the leading cause of acquired epilepsy and convulsive conditions worldwide. Research into the pathophysiology of the disease and appropriate treatment is hindered by lack of cost-effective and physiologically similar animal models. We generated a novel rat neurocysticercosis model using intracranial infection with activated T. solium oncospheres. Holtzman rats were infected in two separate groups: the first group was inoculated extraparenchymally and the second intraparenchymally, with different doses of activated oncospheres. The groups were evaluated at three different ages. Histologic examination of the tissue surrounding T. solium cysticerci was performed. Results indicate that generally infected rats developed cysticerci in the brain tissue after 4 months, and the cysticerci were observed in the parenchymal, ventricle, or submeningeal brain tissue. The route of infection did not have a statistically significant effect on the proportion of rats that developed cysticerci, and there was no dependence on infection dose. However, rat age was crucial to the success of the infection. Epilepsy was observed in 9% of rats with neurocysticercosis. In histologic examination, a layer of collagen tissue, inflammatory infiltrate cells, perivascular infiltrate, angiogenesis, spongy change, and mass effect were observed in the tissue surrounding the cysts. This study presents a suitable animal model for the study of human neurocysticercosis. PMID:26216286

  19. Novel rat model for neurocysticercosis using Taenia solium.

    Science.gov (United States)

    Verastegui, Manuela R; Mejia, Alan; Clark, Taryn; Gavidia, Cesar M; Mamani, Javier; Ccopa, Fredy; Angulo, Noelia; Chile, Nancy; Carmen, Rogger; Medina, Roxana; García, Hector H; Rodriguez, Silvia; Ortega, Ynes; Gilman, Robert H

    2015-08-01

    Neurocysticercosis is caused by Taenia solium infecting the central nervous system and is the leading cause of acquired epilepsy and convulsive conditions worldwide. Research into the pathophysiology of the disease and appropriate treatment is hindered by lack of cost-effective and physiologically similar animal models. We generated a novel rat neurocysticercosis model using intracranial infection with activated T. solium oncospheres. Holtzman rats were infected in two separate groups: the first group was inoculated extraparenchymally and the second intraparenchymally, with different doses of activated oncospheres. The groups were evaluated at three different ages. Histologic examination of the tissue surrounding T. solium cysticerci was performed. Results indicate that generally infected rats developed cysticerci in the brain tissue after 4 months, and the cysticerci were observed in the parenchymal, ventricle, or submeningeal brain tissue. The route of infection did not have a statistically significant effect on the proportion of rats that developed cysticerci, and there was no dependence on infection dose. However, rat age was crucial to the success of the infection. Epilepsy was observed in 9% of rats with neurocysticercosis. In histologic examination, a layer of collagen tissue, inflammatory infiltrate cells, perivascular infiltrate, angiogenesis, spongy change, and mass effect were observed in the tissue surrounding the cysts. This study presents a suitable animal model for the study of human neurocysticercosis.

  20. Ultrastructural localization of alkaline phosphatase in the eggs of Hydatigera taeniaeformis (Taenia taeniaeformis).

    Science.gov (United States)

    Ajayi, S T; Smith, B F; LeFlore, W B

    1985-01-01

    Freshly shed gravid proglottids from a three-month-old infection of Hydatigera taeniaeformis collected from the faecal droppings of infected cats were used for this study. They were treated for transmission electron microscopy (TEM) followed by incubation using the lead precipitate method. Control sections were incubated in a substrate-free medium, a substrate medium containing 1.0 mM sodium fluoride (NaF) (an inhibitor), and the last sections were denatured at 90 degrees C for 1 min prior to incubation. Intensive alkaline phosphatase activity in the embryophoric blocks and the outer embryophoric membrane was revealed. The reaction products were also indicated in the oncospheral membrane. However, no enzyme activity was seen in any other part of the egg. The enzyme was also absent in the control sections. The presence of alkaline phosphatase activity in the outer embryophoric and oncospheral membranes suggested that this enzyme may be involved in carbohydrate metabolism and nutritional absorption, and also may play a role in the transport of nutrients and other substances from the adult to the developing embryo, respectively.

  1. Protection of pigs against Taenia solium cysticercosis by immunization with novel recombinant antigens.

    Science.gov (United States)

    Gauci, Charles G; Jayashi, César M; Gonzalez, Armando E; Lackenby, Julia; Lightowlers, Marshall W

    2012-06-06

    Recombinant antigens from the oncosphere stage of the parasite Taenia solium were expressed in Escherichia coli. The TSOL16, TSOL45-1A and TSOL45-1B recombinant antigens, each consisting of fibronectin type III (FnIII) domain S, were produced as fusion proteins with glutathione S-transferase (GST) and maltose binding protein (MBP). Groups of pigs were immunized twice with the GST fusions of the antigens and boosted a third time with the MBP fusions prior to receiving a challenge infection with T. solium eggs. The TSOL16 antigen was found to be capable of inducing high levels of immunity in pigs against a challenge infection with T. solium. Immunological investigations identified differences in immune responses in the pigs vaccinated with the various antigens. The results demonstrate that the TSOL16 antigen could be a valuable adjunct to current porcine vaccination approaches and may allow the further development of new vaccination strategies against T. solium cysticercosis.

  2. Echinococcus granulosus genomics: a new dawn for improved diagnosis, treatment, and control of echinococcosis.

    Science.gov (United States)

    Zhang, Wenbao; Wang, Shengyue; McManus, Donald P

    2014-01-01

    Cystic echinococcosis (CE) is a cosmopolitan disease caused by the dog tapeworm Echinococcus granulosus. The disease is difficult to diagnose, treat, and control and is responsible for considerable human morbidity and mortality globally. There is an urgent need for new diagnostic tests and new drugs for treatment of CE and the development of a vaccine against adult worms of E. granulosus in dogs. We recently presented a draft genomic sequence for the worm comprising 151.6 Mb encoding 11,325 proteins. We undertook an extensive comparative analysis of the E. granulosus transcriptome using representative life stages (protoscoleces, cyst germinal cells and membranes, adult worms, and oncospheres) to explore different aspects of tapeworm biology and parasitism. The genome and transcriptome of E. granulosus provide a unique platform for post-genomic research and to facilitate the development of new, effective treatments and interventions for echinococcosis control.

  3. The Target of Benzimidazole Carbamate Against Cysticerci cellulosae

    Institute of Scientific and Technical Information of China (English)

    LI Qing-zhang; HAO Yan-hong; GAO Xue-jun; GAO Wen-xue; ZHAO Bing

    2007-01-01

    To study the target of benzimidazole carbamate drugs against Cysticerci cellulosae and give a theoretical basis for type evolution and new drug design, the changes of key enzyme activities and metabolite contents in the pathway of energy metabolism in C. cellulosae in vitro and in vivo were tested with albendazole and oxfendazole, respectively. Both albendazole and oxfendazole inhibited the pathways of anaerobic glycolysis, partial inversed tricarboxylic acid cycle of Taenia Solium oncosphere, immature and mature Cysticerci in vitro, and immature and mature Cysticerci in vivo to a certain degree, and enhanced fat decomposing, amino acid decomposing, xanthine decomposing metabolism, and on the other hand, the absorption of glucose was hindered; furthermore, both albendazole and oxfendazole inhibited the activities of the fumaric reductase (FR) complex noncompetently in vitro. Benzimidazole carbamate drugs could inhibit the activities of FR complex noncompetently and hinder the absorption of glucose.

  4. Analysis of antibody responses to Hymenolepis nana infection in mice by the enzyme-linked immunosorbent assay and immunoprecipitation.

    Science.gov (United States)

    Ito, A; Honey, R D; Scanlon, T; Lightowlers, M W; Rickard, M D

    1988-05-01

    Serum antibody responses in two strains of mice infected with embryonated eggs of Hymenolepis nana were analysed by the enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation (IP) using sodium deoxycholate (DOC)-solubilized antigens prepared from embryonated eggs (eggs), mouse-derived cysticercoids (cysts) and adult tapeworms with immature segments only (adults). Highly susceptible dd mice, which harbour mature tapeworms for a long period (greater than 70 days), produced high levels of antibodies to all three different stages of H. nana. BALB/c mice, almost all of which expel adult tapeworms by 30 days after infection, produced high levels of antibody against egg antigens only. The high antibody titres to cyst and adult antigens in dd mice did not lead to expulsion of the worms. However, worms are rejected early in BALB/c mice when there is little or no detectable serum antibody. The antibody responses to eggs seen in BALB/c mice which had long since shed their adult worms were probably due to ingestion of eggs from faeces of other infected mice. Antibodies to eggs were not detected in BALB/c mice which were initially inoculated with eggs (day 0) and then treated with praziquantel on day 6 after the tissue phase of infection only. The different antibody responses to egg antigens and the other two antigens (cyst and adult) in BALB/c mice suggest a difference in antigen specificity between eggs and both cysts and adults. A major antigen component with Mr 32,000 appears to be specific to the egg (or oncosphere) stage of H. nana. Antibody to this major component of eggs was absorbed only with intact eggs, but not with intact cysts nor adults with immature segments only, so that the antigen appears to be on the surface of the oncosphere.

  5. Cestodes from Hector's beaked whale ( Mesoplodon hectori ) and spectacled porpoise ( Phocoena dioptrica ) from Argentinean waters.

    Science.gov (United States)

    Nikolov, Pavel N; Cappozzo, H Luis; Berón-Vera, Bárbara; Crespo, Enrique A; Raga, J Antonio; Fernández, Mercedes

    2010-08-01

    Single individuals of 2 little-known cetacean species, Mesoplodon hectori and Phocoena dioptrica , stranded and died on the coast of Argentina (Buenos Aires and Chubut provinces, respectively) and were studied for the presence of helminths. The cestodes found were described and illustrated using light microscopy. The following cestode taxa were recovered: Tetrabothrius ( Tetrabothrius ) hobergi n. sp. (several fragmented specimens, at least 1 gravid) and Tetrabothrius ( s.l. ) sp. 1 (several fragmented immature specimens) from M. hectori , and Tetrabothrius ( s.l. ) sp. 2 (single fragmented immature specimen) and 2 morphotypes of tetraphyllidean larvae from P. dioptrica. Tetrabothrius ( T. ) hobergi n. sp. can be distinguished from Tetrabothrius ( T. ) forsteri by the greater number of testes and larger eggs and oncospheres, from Tetrabothrius ( T. ) curilensis by the smaller testes and vitellarium, the shape and size of the ovary, and the larger oncospheres and longer embryonic hooks, and from Tetrabothrius ( T. ) sp. from Ziphius cavirostris by the narrower strobila, smaller scolex, and smaller number of testes. The generic designations of Tetrabothrius ( s.l. ) sp. 1 and Tetrabothrius ( s.l. ) sp. 2 were based on the scolex morphology. Tetrabothrius ( s.l. ) sp. 1 is closest to Tetrabothrius ( T. ) forsteri and Tetrabothrius ( Biamniculus ) innominatus based on the number of testes, while the scolex size of Tetrabothrius ( Tetrabothrius ) sp. 2 is within the variability range reported for Tetrabothrius ( T. ) forsteri . More definite identification of the 2 species was not possible due to the condition of the available material. The present study provides the first descriptions of cestodes from M. hectori and P. dioptrica , thus enriching the knowledge regarding the helminths of insufficiently studied marine mammals.

  6. THE APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF CESTODES

    Directory of Open Access Journals (Sweden)

    John H. Cross

    2012-09-01

    Full Text Available Cestodes or tapeworms are found in vertebrate hosts worldwide. There are a great many species, but few have received much attention in biotechnologic research. Those that have been studied in any detail have been those of importance to veterinary and human medicine. The application of biotechnology to the study of taeniids has been gaining momentum in recent years. Research has been done to improve the diagnosis of larval taeniid infections, especially cysticercosis. There have been improvements in serologic testing using refined and purified antigens readily available from one species to detect antibodies of another. (Taenia hydatigena antigens are used to detect Cysticercus bovis and Cysticercus cellulosae. The use of Western blots of tapeworm antigens (T. solium, T. crassiceps, Echinococcus granulosus has been shown to be effective in neurocysticercosis and hydatid diseases. Studies with monoclonal antibodies have also been found to be of interest. Anti-oncospheral monoclonal antibodies have been developed to distinguish eggs of E. granulosis from other taeniid eggs. In another study, monoclonal antibodies from oncospheres of T.saginata conferred protection against oral infections with T.saginata eggs in calves. Other investigators reported vaccines against Cysticercus fasciolaris by a T. taeniaeformis antigen expressed in Escherichia coli. Studies on DNA have been gaining momentum. DNA-based techniques have been used to detect inter- and intraspecific variations in Echinococcus and to characterize isolates of E.granulosus. DNA probes in Southern blot analysis have been used to discriminate taeniid species. Taenia saginata in the Far East has become an enigma. Although the parasite is morphologically T.saginata, the definitive host for the parasite is not clear. Studies have shown the pig to be a possible intermediate host with larval development similar to T.solium, but in pig liver rather than muscle. In recent comparative studies with T

  7. Cloning and Characterization of Two Potent Kunitz Type Protease Inhibitors from Echinococcus granulosus.

    Science.gov (United States)

    Ranasinghe, Shiwanthi L; Fischer, Katja; Zhang, Wenbao; Gobert, Geoffrey N; McManus, Donald P

    2015-12-01

    The tapeworm Echinococcus granulosus is responsible for cystic echinococcosis (CE), a cosmopolitan disease which imposes a significant burden on the health and economy of affected communities. Little is known about the molecular mechanisms whereby E. granulosus is able to survive in the hostile mammalian host environment, avoiding attack by host enzymes and evading immune responses, but protease inhibitors released by the parasite are likely implicated. We identified two nucleotide sequences corresponding to secreted single domain Kunitz type protease inhibitors (EgKIs) in the E. granulosus genome, and their cDNAs were cloned, bacterially expressed and purified. EgKI-1 is highly expressed in the oncosphere (egg) stage and is a potent chymotrypsin and neutrophil elastase inhibitor that binds calcium and reduced neutrophil infiltration in a local inflammation model. EgKI-2 is highly expressed in adult worms and is a potent inhibitor of trypsin. As powerful inhibitors of mammalian intestinal proteases, the EgKIs may play a pivotal protective role in preventing proteolytic enzyme attack thereby ensuring survival of E. granulosus within its mammalian hosts. EgKI-1 may also be involved in the oncosphere in host immune evasion by inhibiting neutrophil elastase and cathepsin G once this stage is exposed to the mammalian blood system. In light of their key roles in protecting E. granulosus from host enzymatic attack, the EgKI proteins represent potential intervention targets to control CE. This is important as new public health measures against CE are required, given the inefficiencies of available drugs and the current difficulties in its treatment and control. In addition, being a small sized highly potent serine protease inhibitor, and an inhibitor of neutrophil chemotaxis, EgKI-1 may have clinical potential as a novel anti-inflammatory therapeutic.

  8. THE APPLICATION OF BIOTECHNOLOGY TO THE STUDY OF CESTODES

    Directory of Open Access Journals (Sweden)

    John H. Cross

    2012-09-01

    Full Text Available Cestodes or tapeworms are found in vertebrate hosts worldwide. There are a great many species, but few have received much attention in biotechnologic research. Those that have been studied in any detail have been those of importance to veterinary and human medicine. The application of biotechnology to the study of taeniids has been gaining momentum in recent years. Research has been done to improve the diagnosis of larval taeniid infections, especially cysticercosis. There have been improvements in serologic testing using refined and purified antigens readily available from one species to detect antibodies of another. (Taenia hydatigena antigens are used to detect Cysticercus bovis and Cysticercus cellulosae. The use of Western blots of tapeworm antigens (T. solium, T. crassiceps, Echinococcus granulosus has been shown to be effective in neurocysticercosis and hydatid diseases. Studies with monoclonal antibodies have also been found to be of interest. Anti-oncospheral monoclonal antibodies have been developed to distinguish eggs of E. granulosis from other taeniid eggs. In another study, monoclonal antibodies from oncospheres of T.saginata conferred protection against oral infections with T.saginata eggs in calves. Other investigators reported vaccines against Cysticercus fasciolaris by a T. taeniaeformis antigen expressed in Escherichia coli. Studies on DNA have been gaining momentum. DNA-based techniques have been used to detect inter- and intraspecific variations in Echinococcus and to characterize isolates of E.granulosus. DNA probes in Southern blot analysis have been used to discriminate taeniid species. Taenia saginata in the Far East has become an enigma. Although the parasite is morphologically T.saginata, the definitive host for the parasite is not clear. Studies have shown the pig to be a possible intermediate host with larval development similar to T.solium, but in pig liver rather than muscle. In recent comparative studies with T

  9. Excretory/secretory-products of Echinococcus multilocularis larvae induce apoptosis and tolerogenic properties in dendritic cells in vitro.

    Directory of Open Access Journals (Sweden)

    Justin Komguep Nono

    Full Text Available BACKGROUND: Alveolar echinococcosis, caused by Echinococcus multilocularis larvae, is a chronic disease associated with considerable modulation of the host immune response. Dendritic cells (DC are key effectors in shaping the immune response and among the first cells encountered by the parasite during an infection. Although it is assumed that E.multilocularis, by excretory/secretory (E/S-products, specifically affects DC to deviate immune responses, little information is available on the molecular nature of respective E/S-products and their mode of action. METHODOLOGY/PRINCIPAL FINDINGS: We established cultivation systems for exposing DC to live material from early (oncosphere, chronic (metacestode and late (protoscolex infectious stages. When co-incubated with Echinococcus primary cells, representing the invading oncosphere, or metacestode vesicles, a significant proportion of DC underwent apoptosis and the surviving DC failed to mature. In contrast, DC exposed to protoscoleces upregulated maturation markers and did not undergo apoptosis. After pre-incubation with primary cells and metacestode vesicles, DC showed a strongly impaired ability to be activated by the TLR ligand LPS, which was not observed in DC pre-treated with protoscolex E/S-products. While none of the larvae induced the secretion of pro-inflammatory IL-12p70, the production of immunosuppressive IL-10 was elevated in response to primary cell E/S-products. Finally, upon incubation with DC and naïve T-cells, E/S-products from metacestode vesicles led to a significant expansion of Foxp3+ T cells in vitro. CONCLUSIONS: This is the first report on the induction of apoptosis in DC by cestode E/S-products. Our data indicate that the early infective stage of E. multilocularis is a strong inducer of tolerance in DC, which is most probably important for generating an immunosuppressive environment at an infection phase in which the parasite is highly vulnerable to host attacks. The

  10. Basic and applied immunology in cestode infections: from Hymenolepis to Taenia and Echinococcus.

    Science.gov (United States)

    Ito, A

    1997-10-01

    In larval cestode infections, it is well established that the intermediate mammalian host infected with egg-derived metacestodes in the tissue becomes completely immune to reinfection with eggs, whereas autoinfection has been conceived to occur in Hymenolepis nana/mouse (and human) and Taenia solium/human systems when these hosts are initially infected with metacestode-derived adult tapeworms in the lumen. In this review paper, the first topic is immunobiology of H. nana/mouse system on the reinfection immunity in order to get critical information as to how the initially ingested parasite (eggs or metacestodes) can develop into adult worms and how autoinfection does or does not occur in immunocompetent mice, since H. nana can complete its whole life cycle in the mouse intestinal tissue and lumen. When mice are infected with eggs (= oncospheres) of H. nana, they become immune to challenge infections with eggs within a few days (early response) and with cysticercoids within two weeks (late response). The initially established adult worms are expelled later (worm expulsion response). When mice are infected with cysticercoids, either derived from beetles or mice, they become immune to challenge infection with cysticercoids but not with eggs. Therefore, autoinfection occurs in the intestinal tissue for the establishment of cysticercoids in the tissue but never occurs in the intestinal lumen for the establishment of adult worms in immunocompetent mice. The second topic is vaccination trial against challenge infection with eggs of Asian Taenia in pigs. Pigs vaccinated with frozen oncospheres of Asian Taenia from Taiwan or Korea or T. saginata showed very strong resistance, whereas pigs vaccinated with those of T. solium showed partial resistance only. It is suggested that Asian Taenia is much closer to T. saginata than T. solium from the immunobiological viewpoint. The third topic is immunodiagnosis of echinococcosis and cysticercosis. Immunoblot analysis has revealed

  11. STUDIES ON THE IMMUNOTHERAPY OF CYSTICERCOSIS%猪囊尾蚴病免疫治疗研究

    Institute of Scientific and Technical Information of China (English)

    张京; 张中庸; 李靓如; 马春艳; 吴莲英

    2000-01-01

    本研究进行了两次攻虫-免疫实验,第一次实验应用仔猪20头,于攻虫前两周分别用1,000万和2,000万猪囊尾蚴细胞加代谢产物疫苗进行免疫,然后攻虫,攻虫量为6000枚/头人有钩绦虫六钩蚴虫卵;第二次实验应用仔猪10头,先攻虫卵38000枚/头38天后再用1,000万猪囊尾蚴细胞加代谢产物疫苗免疫,然后剖检猪体内虫体。结果第一次实验的两个组100%的猪,体内囊尾蚴虫体发生了钙化,第二次实验有66.7%的猪,体内囊尾蚴发生钙化现象,两次实验猪的平均钙化率为87.5%,猪囊尾蚴细胞灭活疫苗有显著的免疫治疗作用。%The research on the immunotherapy of Cysticercosis includes two experiments. 20 heads of piglets were used in the first experiment. Two weeks before attacking-larvae ,we immunized the experiment piglets with ten or twenty million cell vaccine of Cysticercus Cellulosae cell line's cells and its metabolite respectively. Than attacked with larvae. the volume is 6.000 ova of Taenia Solium Oncosphere per heads. In another experiment 10 heads of piglets were used. After 38 days of attacking-larvae of Taenia Solium Oncosphere Ova,we immunized the experiment piglets with ten millon cell vaccine of Cysticercus Cellulosae cell line's cells and its metabolite. After a certain time ,we dissected all of the experiment piglets and examined the state of infected Cysticercus Cellulosae in the body. And the results are as follows:in the first experiment, 100 percent of the two groups of piglets calcifid in that of the Cysticercuses;and in the second experiment. We found that 66. 7 percent of the piglets with calcified Cysticercuses. The average calcification rate of the twice exper iments is 87. 5 percent. The inactivity cell vaccine of Cysticercus Cellulosae is a good agent of immunity treatment.

  12. In vivo viability of Echinococcus multilocularis eggs in a rodent model after different thermo-treatments.

    Science.gov (United States)

    Federer, Karin; Armua-Fernandez, Maria Teresa; Hoby, Stefan; Wenker, Christian; Deplazes, Peter

    2015-07-01

    Echinococcus multilocularis is the causative agent of alveolar echinococcosis, a serious and emerging zoonotic disease in many parts of the northern hemisphere. Humans but also primates and other accidental hosts can acquire the infection by the ingestion of eggs excreted by the carnivore definitive hosts, e.g. after hand contact with egg-contaminated environments or by consumption of contaminated food or beverages. The goal of this study was to develop a sensitive in vivo method to determine the viability of E. multilocularis eggs and to establish suitable conditions (optimal temperature, exposure time and humidity) for their (prophylactic) inactivation. The sensitivity of a rodent model was evaluated and, conclusively, C57Bl/6 mice were most susceptible to subcutaneous inoculation of small numbers of sodium hypochlorite-resistant oncospheres, even more than to oral inoculation of mature eggs. In the second part of the study, various combinations of exposure temperature (between 45 °C and 80 °C), times (between 30 min and 180 min) and relative humidity (70% vs. suspended in water) were tested. After heat treatment in an incubator, the sodium hypochlorite resistance test was used to assess in vitro egg viability at the time of inoculation. Subsequently, the infectivity of the oncospheres was evaluated by subcutaneous inoculation in mice. Eggs exposed to increasing temperatures were more resistant to heat if suspended in water as compared to eggs exposed on a filter paper at 70% relative humidity. As survival of eggs in water droplets on the vegetables cannot be excluded, further experiments were performed with eggs suspended in water only. Eggs were infectious after heat exposure at 65 °C for up to 120 min, however, no echinococcosis developed after treatment of the eggs at 65 °C for 180 min or at 70, 75 and 80 °C for 7.5, 15 or 30 min. Copyright © 2015. Published by Elsevier Inc.

  13. Peroral Echinococcus multilocularis egg inoculation in Myodes glareolus, Mesocricetus auratus and Mus musculus (CD-1 IGS and C57BL/6j

    Directory of Open Access Journals (Sweden)

    Ian David Woolsey

    2016-08-01

    Full Text Available Echinococcus multilocularis transmission predominantly occurs in Europe between the red fox (Vulpes vulpes and various species of rodent intermediate hosts. We infected 3 species of rodent, Myodes glareolus (n = 47, Mesocricetus auratus (n = 11 and outbred Mus musculus (CD-1 IGS (n = 9 with an E. multilocularis egg suspension that contained 100 eggs with viable oncospheres and performed post mortem examination 6, 8 (M. glareolus and 10 weeks post inoculation (wpi. C57BL/6j mice (n = 4 were used as positive controls as they have been shown to exhibit macroscopic liver lesions 4 wpi. To the best of our knowledge, this is the first study to experimentally assess susceptibility in the ostensibly competent host M. glareolus. Lesions were only detected in 2 of 47 M. glareolus (4.3% at 8 and 10 wpi and although both contained protoscolices (1675 at 8 wpi and 88 at 12 wpi the low percentage of infected animals brings into question their role as transmitters of the parasite. Significant differences were observed between inbred and outbred mice with E. multilocularis infection in the former demonstrating increased establishment (p ≤ 0.0001 and growth (p ≤ 0.0001. No lesions were found in all 11 M. auratus.

  14. TsAg5, a Taenia solium cysticercus protein with a marginal trypsin-like activity in the diagnosis of human neurocysticercosis.

    Science.gov (United States)

    Rueda, Analiz; Sifuentes, Cecilia; Gilman, Robert H; Gutiérrez, Andrés H; Piña, Ruby; Chile, Nancy; Carrasco, Sebastián; Larson, Sandra; Mayta, Holger; Verástegui, Manuela; Rodriguez, Silvia; Gutiérrez-Correa, Marcel; García, Héctor H; Sheen, Patricia; Zimic, Mirko

    2011-12-01

    Neurocysticercosis is an endemic parasitic disease caused by Taenia solium larva. Although the mechanism of infection is not completely understood, it is likely driven by proteolytic activity that degrades the intestinal wall to facilitate oncosphere penetration and further infection. We analyzed the publicly available T. solium EST/DNA library and identified two contigs comprising a full-length cDNA fragment very similar to Echinococcus granulosus Ag5 protein. The T. solium cDNA sequence included a proteolytic trypsin-like-domain in the C-terminal region, and a thrombospondin type-1 adherence-domain in the N-terminal region. Both the trypsin-like and adherence domains were expressed independently as recombinant proteins in bacterial systems. TsAg5 showed marginal trypsin-like activity and high sequence similarity to Ag5. The purified antigens were tested in a Western immunoblot assay to diagnose human neurocysticercosis. The sensitivity of the trypsin-like-domain was 96.36% in patients infected with extraparenchymal cysts, 75.44% in patients infected with multiple cysts, and 39.62% in patients with a single cyst. Specificity was 76.70%. The thrombospondin type-1 adherence-domain was not specific for neurocysticercosis.

  15. Recombinant antigens for immunodiagnosis of cystic echinococcosis

    Directory of Open Access Journals (Sweden)

    Li Jun

    2004-01-01

    Full Text Available Three cDNAs, termed EpC1, TPxEg and EgG5, were isolated by immunoscreening from an Echinococcus granulosus cDNA library. The recombinant phages exhibited strong reactivity with sera from humans with confirmed cystic echinococcosis (CE and with sera from mice infected with E. granulosus oncospheres. The cDNAs were subcloned into a pET vector, expressed as fusion proteins tagged with GST and affinity purified against the GST tag. Of the three recombinant proteins, EpC1 achieved the highest performance for serodiagnosis of CE in Western blot analysis using a panel of clinically defined human sera to initially address the sensitivity and specificity of the molecules. The protein yielded an overall sensitivity of 92.2% and specificity of 95.6%, levels unprecedented taking into account the large panel of 896 human sera that were tested. The strategy used may also prove suitable for improved immunodiagnosis of other parasitic infections.

  16. A standardised terminology of the embryonic envelopes and associated developmental stages of tapeworms (Platyhelminthes: Cestoda).

    Science.gov (United States)

    Conn, David Bruce; Swiderski, Zdzisław

    2008-03-01

    Over the past 40 years, much has been published on the ultrastructure and cellular development of embryonic structures in a wide range of cestodes. However, the literature contains many discrepancies in both terminology and interpretations because of the facts that these organisms are phylogenetically diverse within their respective orders and families, the habitats that affect embryonic envelope structure are diverse, and the work has been done in various laboratories around the world. This review and synthesis was initiated by a working group of biologists from around the world convened at the Fifth International Workshop on Cestode Systematics and Phylogeny in Ceské Budejovice, at the Institute of Parasitology of the Biology Centre, Academy of Sciences of the Czech Republic. It brings together the data from published work and establishes a uniform terminology and interpretation based on the data as they are presented. A consensus was reached for standardised definitions of the oncosphere, hexacanth, coracidium, embryonic envelopes, outer envelope, inner envelope, embryophore, vitelline capsule, shell, and outer coat. All of these are defined as components of the embryo or its vitellocyte-derived or uterine-derived coatings.

  17. Reactive oxygen intermediates from eosinophils in mice infected with Hymenolepis nana.

    Science.gov (United States)

    Niwa, A; Miyazato, T

    1996-06-01

    A large number of eosinophils were recruited to the intestinal villi after infection with Hymenolepis nana. Eosinophil numbers were increased more rapidly in challenged mice than in primary infected mice. Local intestinal eosinophils from challenged mice showed more extracellular oxygen radical release, as assessed by histochemical methods using nitro blue tetrazolium, accompanied with tissue injury and larval degradation. Intestinal eosinophils isolated from the lamina propria induced specific oxygen radical generation in response to H. nana oncosphere extract as measured by luminol-dependent chemiluminescence. This response was stronger in challenged mice than in primary infected mice. Radical generation from uninfected mice was negligible. Lipid peroxidation in the small intestine, as measured by formation of malondialdehyde, was increased during H. nana challenge infection, the peak activity coinciding with the elimination of challenge larvae. Continuous administration of a NADPH oxidase inhibitor to sensitized mice interfered with the degeneration of challenge larvae. These results suggest that intestinal eosinophils may be the major contributor to oxygen radical production in response to H. nana and that reactive oxygen species may play a part of effector molecule in the resistance to reinfection with H. nana.

  18. Hymenolepis microstoma: direct life cycle in immunodeficient mice.

    Science.gov (United States)

    Andreassen, J; Ito, A; Ito, M; Nakao, M; Nakaya, K

    2004-03-01

    The mouse bile duct tapeworm Hymenolepis microstoma requires beetles as the obligatory intermediate host. However, when congenitally athymic NMRI-nu mice were infected with the mature tapeworm and allowed to eat their own faeces with tapeworm eggs, the oncospheres penetrated the intestinal tissue and developed to cysticercoids. After excysting, growth to adult worms occurs in the lumen of the small intestine and bile duct. Furthermore, the same happened when NMRI-nu mice, non-obese diabetic severe combined immunodeficiency (NOD/Shi-scid) mice and NOD/Shi-scid, IL-2 Rgamma(null) (NOG) mice were orally inoculated with shell-free eggs of this parasite. Differences between the cysticercoids of H. microstoma and H. nana developed in the mouse intestinal tissues were: (i) the time course for the development of fully matured cysticercoids of H. microstoma in mice was about 11 days but only 4 days for H. nana; and (ii) cysticercoids of H. microstoma developed in mice had a tail while those of H. nana had none.

  19. [Infection of Mice with Normal Immune Function by Taenia asiatica].

    Science.gov (United States)

    Liu, Xiao-yan; Guo, Guang-wu; Chen, Li-hong; Mo, Xing-ze; Yu, Yue-sheng

    2015-08-01

    The Taenia asiatica eggs pre-incubated with sodium hypochlorite solution for 4 min, 6 min and 8 mins were subcutaneously injected into mice with normal immune function(groups Al-A3 respectively, n=20 in each) and mice with immunosuppression (groups B1-B3, n=20 in each). All groups of mice began to show body discomfort on day 5 after infection and develop lumps on the back about on day 15. In groups Al-A3, animal death occurred during days 7-15, with a same survival rate of 95.0%(19/20) and infection rate of 89.4%(17/19), 73.6%(14/19) and 47.3%(9/19) respectively. In groups B1-B3, animal death occurred during days 7-50, with survival rate of 60%(13/20), 55%(11/20)and 55%(11/20) and infection rate of 76.9% (10/13), 54.5% (6/11) and 45.4% (5/11) respectively. After the scolex of cysticercus was evaginated with 15% pig bile, four suckers, an apparent rostellum and two distinct hook-like puncta structures were seen. These results indicate that mice with normal immune function can be used as a replacement of immunosuppressive mice to establish a T. asiatica oncosphere infection model. In addition, the T. asiatica eggs pre-incubated with sodium hypochlorite solution for 4 min have the strongest infection ability.

  20. Application of a cDNA microarray for profiling the gene expression of Echinococcus granulosus protoscoleces treated with albendazole and artemisinin.

    Science.gov (United States)

    Lü, Guodong; Zhang, Wenbao; Wang, Jianhua; Xiao, Yunfeng; Zhao, Jun; Zhao, Jianqin; Sun, Yimin; Zhang, Chuanshan; Wang, Junhua; Lin, Renyong; Liu, Hui; Zhang, Fuchun; Wen, Hao

    2014-12-01

    Cystic echinoccocosis (CE) is a neglected zoonosis that is caused by the dog-tapeworm Echinococcus granulosus. The disease is endemic worldwide. There is an urgent need for searching effective drug for the treatment of the disease. In this study, we sequenced a cDNA library constructed using RNA isolated from oncospheres, protoscoleces, cyst membrane and adult worms of E. granulosus. A total of 9065 non-redundant or unique sequences were obtained and spotted on chips as uniEST probes to profile the gene expression in protoscoleces of E. granulosus treated with the anthelmintic drugs albendazole and artemisinin, respectively. The results showed that 7 genes were up-regulated and 38 genes were down-regulated in the protoscoleces treated with albendazole. Gene analysis showed that these genes are responsible for energy metabolism, cell cycle and assembly of cell structure. We also identified 100 genes up-regulated and 6 genes down-regulated in the protoscoleces treated with artemisinin. These genes play roles in the transduction of environmental signals, and metabolism. Albendazole appeared its drug efficacy in damaging cell structure, while artemisinin was observed to increase the formation of the heterochromatin in protoscolex cells. Our results highlight the utility of using cDNA microarray methods to detect gene expression profiles of E. granulosus and, in particular, to understand the pharmacologic mechanism of anti-echinococcosis drugs.

  1. Assessment of protective immune responses against hydatid disease in sheep by immunization with synthetic peptide antigens.

    Science.gov (United States)

    Woollard, D J; Heath, D D; Lightowlers, M W

    2000-08-01

    Four synthetic peptides which comprise the immunodominant linear epitopes of the EG95 recombinant protein, were investigated for their ability to induce host-protective immunity against Echinococcus granulosus in sheep. Sheep were immunized with either free peptide or peptide conjugated to diphtheria toxoid and challenge infected with E. granulosus eggs. All of the peptides elicited specific antibody, but these did not kill the parasite in in vitro culture assays, nor did the peptides induce protection against challenge infection. In contrast, anti-EG95 antibodies affinity purified against each of the 4 peptides were lethal to the parasite in in vitro culture. These affinity-purified antibodies were shown to contain specific antibody to both peptide and EG95. In in vitro inhibition assays, the peptides did not diminish anti-EG95 antibody binding to EG95 or parasite lysis in oncosphere killing assays. These results suggest that the fine specificities of antibodies raised against the recombinant protein are different to those raised against the peptide immunogens and that the majority of the antibody induced by vaccination with EG95 is raised against conformational determinants.

  2. TsAg5, a Taenia solium cysticercus protein with a marginal trypsin-like activity in the diagnosis of human neurocysticercosis

    Science.gov (United States)

    Rueda, Analiz; Sifuentes, Cecilia; Gilman, Robert H.; Gutiérrez, Andrés H.; Piña, Ruby; Chile, Nancy; Carrasco, Sebastián; Larson, Sandra; Mayta, Holger; Verástegui, Manuela; Rodriguez, Silvia; Gutiérrez-Correa, Marcel; García, Héctor H.; Sheen, Patricia; Zimic, Mirko

    2011-01-01

    Neurocysticercosis is an endemic parasitic disease caused by Taenia solium larva. Although the mechanism of infection is not completely understood, it is likely driven by proteolytic activity that degrades the intestinal wall to facilitate oncosphere penetration and further infection. We analyzed the publicly available Taenia solium EST/DNA library and identified two contigs comprising a full-length cDNA fragment very similar to E. granulosus Ag5 protein. The Taenia solium cDNA sequence included a proteolytic trypsin-like-domain in the C-terminal region, and a thrombospondin type-1 adherence-domain in the N-terminal region. Both the trypsin-like and adherence domains were expressed independently as recombinant proteins in bacterial systems. TsAg5 showed marginal trypsin-like activity and high sequence similarity to Ag5. The purified antigens were tested in a Western immunoblot assay to diagnose human neurocysticercosis. The sensitivity of the trypsin-like-domain was 96.36% in patients infected with extraparenchymal cysts, 75.44% in patients infected with multiple cysts, and 39.62% in patients with a single cyst. Specificity was 76.70%. The thrombospondin type-1 adherence-domain was not specific for neurocysticercosis. PMID:21893105

  3. Biodegradable polymeric nanoparticles show high efficacy and specificity at DNA delivery to human glioblastoma in vitro and in vivo.

    Science.gov (United States)

    Guerrero-Cázares, Hugo; Tzeng, Stephany Y; Young, Noah P; Abutaleb, Ameer O; Quiñones-Hinojosa, Alfredo; Green, Jordan J

    2014-05-27

    Current glioblastoma therapies are insufficient to prevent tumor recurrence and eventual death. Here, we describe a method to treat malignant glioma by nonviral DNA delivery using biodegradable poly(β-amino ester)s (PBAEs), with a focus on the brain tumor initiating cells (BTICs), the tumor cell population believed to be responsible for the formation of new tumors and resistance to many conventional therapies. We show transfection efficacy of >60% and low biomaterial-mediated cytotoxicity in primary human BTICs in vitro even when the BTICs are grown as 3-D oncospheres. Intriguingly, we find that these polymeric nanoparticles show intrinsic specificity for nonviral transfection of primary human BTICs over primary healthy human neural progenitor cells and that this specificity is not due to differences in cellular growth rate or total cellular uptake of nanoparticles. Moreover, we demonstrate that biodegradable PBAE/DNA nanoparticles can be fabricated, lyophilized, and then stored for at least 2 years without losing efficacy, increasing the translational relevance of this technology. Using lyophilized nanoparticles, we show transgene expression by tumor cells after intratumoral injection into an orthotopic murine model of human glioblastoma. PBAE/DNA nanoparticles were more effective than naked DNA at exogenous gene expression in vivo, and tumor cells were transfected more effectively than noninvaded brain parenchyma in vivo. This work shows the potential of nonviral gene delivery tools to target human brain tumors.

  4. Ultrasonographic and serologic studies of experimental cysticercosis in rats infected with Taenia taeniaeformis.

    Science.gov (United States)

    Ito, A; Sakakibara, Y; Ma, L; Asano, K; Takiguchi, M; Yasuda, J; Hashimoto, A

    1998-03-01

    Rats experimentally infected with Taenia taeniaeformis were followed-up until 14 weeks post inoculation with eggs (PIE) by hepatic ultrasonographic (US) image and serum antibody response analyses. Parasitic cysts could be imaged as small (2 mm in diameter) anechoic areas with or without a parenthesis-like echogenic small line from two weeks PIE. Immunoblot analysis using antigens from oncospheres (TtO), 30-day-old (TtM-30) and 300-day-old metacestodes (TtM-300) revealed that: (1) these three different developmental stages showed their own unique patterns suggesting the presence of stage-specific antigens; (2) faint IgM antibody responses to some components of TtO and TtM-30 or TtM-300 could be detected from one and two weeks PIE, respectively, and (3) IgG responses to some major components of both TtO and TtM-300, and TtM-30 were easily detected from four and five weeks PIE onwards, respectively. Both TtO and TtM (especially TtM-300) appeared to be highly useful for detection of antibody responses in experimentally infected rats. Due to the easiness in preparation of antigens, fully developed metacestodes may be the best candidate antigens for serodiagnosis. These results strongly suggest that both US image and antibody analyses using antigens from fully developed metacestodes are useful for detection of the early stage of cysticercosis in laboratory animal model.

  5. Immunochemical analysis of Taenia taeniaeformis antigens expressed in Escherichia coli.

    Science.gov (United States)

    Bowtell, D D; Saint, R B; Rickard, M D; Mitchell, G F

    1986-12-01

    Previously we reported the isolation of several Escherichia coli clones expressing fragments of Taenia taeniaeformis antigens as beta-galactosidase fused proteins (Bowtell, Saint, Rickard & Mitchell, 1984). Here we describe the isolation of additional antigen-expressing clones from a larval cDNA library and the assignment of these clones to 7 antigen families. These were isolated with a polyspecific rabbit antiserum raised to the oncosphere. Since this serum was capable of reacting with a large number of antigens, it was important to develop techniques for rapidly determining the identity of the native T. taeniaeformis molecule corresponding to a cloned antigen gene. These included active immunization of rabbits with fused proteins and several techniques involving affinity purification on immobilized fused proteins. The reactivity of the antigen-positive clones with sera from humans infected with related parasites was also assessed. Finally, immunization of mice with several fused proteins failed to protect against subsequent infection, although antigens previously identified as candidate host-protective antigens (Bowtell, Mitchell, Anders, Lightowlers & Rickard, 1983) have yet to be identified in the expression library.

  6. Cloning of linear T-cell epitops of EG95 antigen of Echinococcus granulosus into pGEX4t1 vector and expression analysis by SDS-PAGE

    Directory of Open Access Journals (Sweden)

    Roghayeh Mesri

    2016-12-01

    Full Text Available Background & Objectives: Echinococcus granulosus causes a common disease between humans and animals that called hydatid cyst or hydatidosis. The recombinant EG95 vaccine based on cloning of the 25 KD oncospheral antigen-Eg95- in pGEX stimulated significant humoral and cellular immunity in sheep, but regarding the effect of TH1cell immunity against this parasite and the influence of the linear T-cell epitopes in stimulating this immunity, only the coding sequence of linear T Cell epitopes of EG95 was cloned in pGEX and analyzed it's expression to optimize the qualification of this available vaccine in this study. Materials & Methods: The coding sequence of EG95 linear epitopes by IEDB software were predicted and synthesized. After PCR, the amplicon and pGEX4T1 were digested by xhoI restriction enzyme, the fragment was cloned into pGEX4T1 by heat shock method, and Positive colonies were selected by direct PCR with specific primers. The recombinant protein expression was evaluated in BL21 cells by 10% SDS-PAGE. Results: The coding sequence of EG95 linear T-cell epitopes was amplified by PCR and cloned into pGEX4T1 vector.  The recombinant plasmid was selected with Colony PCR and size difference between intact and recombinant purificated vectors. Recombinant protein expression with high significant concentration was recognized by SDS-PAGE. Conclusion: The EG95 linear T-cell epitopes coding sequence has been successfully cloned into pGEX4T1 vector and expressed into BL21 cells.

  7. Opposite Effects of Soluble Factors Secreted by Adipose Tissue on Proliferating and Quiescent Osteosarcoma Cells.

    Science.gov (United States)

    Avril, Pierre; Duteille, Franck; Ridel, Perrine; Heymann, Marie-Françoise; De Pinieux, Gonzague; Rédini, Françoise; Blanchard, Frédéric; Heymann, Dominique; Trichet, Valérie; Perrot, Pierre

    2016-03-01

    Autologous adipose tissue transfer may be performed for aesthetic needs following resection of osteosarcoma, the most frequent primary malignant tumor of bone, excluding myeloma. The safety of autologous adipose tissue transfer regarding the potential risk of cancer recurrence must be addressed. Adipose tissue injection was tested in a human osteosarcoma preclinical model induced by MNNG-HOS cells. Culture media without growth factors from fetal bovine serum were conditioned with adipose tissue samples and added to two osteosarcoma cell lines (MNNG-HOS and MG-63) that were cultured in monolayer or maintained in nonadherent spheres, favoring a proliferation or quiescent stage, respectively. Proliferation and cell cycle were analyzed. Adipose tissue injection increased local growth of osteosarcoma in mice but was not associated with aggravation of lung metastasis or osteolysis. Adipose tissue-derived soluble factors increased the in vitro proliferation of osteosarcoma cells up to 180 percent. Interleukin-6 and leptin were measured in higher concentrations in adipose tissue-conditioned medium than in osteosarcoma cell-conditioned medium, but the authors' results indicated that they were not implicated alone. Furthermore, adipose tissue-derived soluble factors did not favor a G0-to-G1 phase transition of MNNG-HOS cells in nonadherent oncospheres. This study indicates that adipose tissue-soluble factors activate osteosarcoma cell cycle from G1 to mitosis phases, but do not promote the transition from quiescent G0 to G1 phases. Autologous adipose tissue transfer may not be involved in the activation of dormant tumor cells or cancer stem cells.

  8. Gene cloning, expression, and localization of antigen 5 in the life cycle of Echinococcus granulosus.

    Science.gov (United States)

    Li, Yuzhe; Xu, Hongxu; Chen, Jiajia; Gan, Wenjia; Wu, Weihua; Wu, Weiping; Hu, Xuchu

    2012-06-01

    Antigen 5 (Ag5) has been identified as a dominant component of cyst fluid of Echinococcus granulosus and is considered as a member of serine proteases family, which in other helminth, plays an important role in the egg hatch and larva invasion. However, whether Ag5 is expressed and secreted in all life stages is unknown. In this study, according to the sequence in GenBank, we cloned and sequenced the open reading frame (ORF) of Ag5 gene from the protoscolices of E. granulosus isolated from the sheep in Qinhai Province of China, and found several substitutions and a base insert and deletion in a short region near the stop code, leading to a frameshift mutation which is conserved with the homologue of other cestode. The ORF is 1,455 bp in length, encoding 484 amino acids with a secretory signal peptide. Bioinformatics analysis predicted several phosphorylation and myristoylation sites and a N-glycosylation site and a species-specific linear B epitope in the protein. The ORF was cloned into the plasmid pET28a(+) vector and expressed in Escherichia coli . The recombinant protein was purified by affinity chromatography. Anti-rEgAg5 antiserum was prepared in rats and used to analyze the localization of Ag5 in protoscolex and adult worm by immunofluorescence technique. Results demonstrated that the Ag5 is strongly expressed in the tegument of protoscolex and the embryonic membrane of egg and surface of oncosphere; meanwhile, it is also weakly expressed in tegument of the adult. This study showed that Ag5 is expressed in all stages of life cycle, secreted from the surface of the worm and may be anchored in membrane by its myristoylation sites; these characteristics make it a candidate antigen for diagnosis and vaccine for both intermediate and definitive hosts.

  9. Characterization of the eg95 gene family in the G6 genotype of Echinococcus granulosus.

    Science.gov (United States)

    Alvarez Rojas, Cristian A; Gauci, Charles G; Nolan, Matthew J; Harandi, Majid Fasihi; Lightowlers, Marshall W

    2012-06-01

    Cystic echinococcosis in humans and livestock animals is caused by infection with the cestode parasite Echinococcus granulosus. A number of genotypes of the parasite (designated G1-G10) are known to exist, with the genotype cluster G1-G3 and genotype G6 being responsible for the majority of humans infections. A recombinant vaccine has been developed for use in livestock to prevent infection with E. granulosus. The vaccine is based on the antigen EG95 which is expressed in the early larval stage (oncosphere) of the parasite. The EG95 antigen was originally cloned from the G1 genotype of E. granulosus and the protein has been found to be encoded by members of a small family of related genes in this genotype. Reliable information has not been available about the likely efficacy of the EG95 vaccine against genotypes other than G1. In this study, genomic DNA cloning techniques were used to characterize seven eg95-related gene fragments from the G6 genotype of E. granulosus. Three proteins appear to be encoded by these genes. Considerable differences were found between the EG95 related proteins from the G6 genotype compared with the EG95 protein from the G1 genotype. These differences suggest that the EG95-related proteins from the G6 genotype may have different antigenic epitopes compared with the current vaccine antigen. Data presented in this study have implications for future vaccine design and provide the information that would enable a G6 genotype-specific vaccine to be developed against E. granulosus, should this be considered a desirable addition to the available tools for control of cystic echinococcosis transmission.

  10. Functional expression and characterization of Echinococcus granulosus thioredoxin peroxidase suggests a role in protection against oxidative damage.

    Science.gov (United States)

    Li, Jun; Zhang, Wen-Bao; Loukas, Alex; Lin, Ren-Yong; Ito, Akira; Zhang, Li-Hua; Jones, Malcolm; McManus, Donald P

    2004-02-01

    A full-length cDNA sequence coding for Echinococcus granulosus thioredoxin peroxidase (EgTPx) was isolated from a sheep strain protoscolex cDNA library by immunoscreening using a pool of sera from mice infected with oncospheres. EgTPx expressed as a fusion protein with glutathione S-transferase (GST) exhibited significant thiol-dependent peroxidase activity that protected plasmid DNA from damage by metal-catalyzed oxidation (MCO) in vitro. Furthermore, the suggested antioxidant role for EgTPx was reinforced in an in vivo assay, whereby its expression in BL21 bacterial cells markedly increased the tolerance and survival of the cells to high concentrations of H2O2 compared with controls. Immunolocalization studies revealed that EgTPx was specifically expressed in all tissues of the protoscolex and brood capsules. Higher intensity of labelling was detected in many, but not all, calcareous corpuscle cells in protoscoleces. The purified recombinant EgTPx protein was used to screen sera from heavily infected mice and patients with confirmed hydatid infection. Only a portion of the sera reacted positively with the EgTPx-GST fusion protein in Western blots, suggesting that EgTPx may form antibody-antigen complexes or that responses to the EgTPx antigen may be immunologically regulated. Recombinant EgTPx may prove useful for the screening of specific inhibitors that could serve as new drugs for treatment of hydatid disease. Moreover, given that TPx from different parasitic phyla were phylogenetically distant from host TPx molecules, the development of antiparasite TPx inhibitors that do not react with host TPx might be feasible.

  11. Synergetic effect of Egyptian propolis in immunization of BALB/c mice against bovine cysticercosis

    Institute of Scientific and Technical Information of China (English)

    Omnia; Mohamed; Kandil; Somia; Ayesh; Nassar; Soad; Mohamed; Nasr; Hatem; Abdel; Mawgoud; Shalaby; Seham; Hendawy; Faragalla; Mohamed; El; Moghazy

    2015-01-01

    Objective: To evaluate the synergetic effect of an ethanolic extract of Egyptian propolis in immunization of BALB/c mice with Taenia saginata(T. saginata) crude antigen against bovine cysticercosis, with reference to its effects on liver and kidney functions.Methods: Sixty female mice BALB/c strain weighing 20 to 25 g and 6-8 weeks old were randomly allocated into six groups of ten mice each. Mice in groups 1 and 2(G1 and G2) were immunized intraperitoneally with 100 μg of T. saginata crude antigen in 100 μL phosphate buffer saline emulsified in Freund’s adjuvant. Besides, the mice in G2 were administered with propolis extract simultaneously with immunization. Control mice were either administered with propolis extract(G3) or injected with the same volume of phosphate buffer saline emulsified in Freund’s adjuvant(G4). The mice in G5 were non-immunized infected control while, those in G6 were non-immunized non-infected control. Two weeks after the last immunization, each mouse was challenged intraperitoneally with 5 000 oncospheres except those of G6. Ethanolic extract of propolis was prepared at a dose 50 mg/kg body weight.Results: After 24 weeks of challenge, the mice in G2 showed the highest level of protection(100%), with no cyst being detected rather than mice in G1(33.3% protection). Additionally,the ELISA results, in this study, showed higher antibody titer in G2 with reduction the alteration in liver and kidney functions compared to G1.Conclusions: Egyptian propolis could increase the level of protection against experimental challenge infection with T. saginata eggs when administered simultaneously with immunization. Furthermore, it could enhance the production of antibodies to immunized antigen and decrease the alteration in liver and kidney functions.

  12. Mesenchymal stem cells increase proliferation but do not change quiescent state of osteosarcoma cells: Potential implications according to the tumor resection status

    Science.gov (United States)

    Avril, Pierre; Le Nail, Louis-Romée; Brennan, Meadhbh Á.; Rosset, Philippe; De Pinieux, Gonzague; Layrolle, Pierre; Heymann, Dominique; Perrot, Pierre; Trichet, Valérie

    2015-01-01

    Conventional therapy of primary bone tumors includes surgical excision with wide resection, which leads to physical and aesthetic defects. For reconstruction of bone and joints, allografts can be supplemented with mesenchymal stem cells (MSCs). Similarly, adipose tissue transfer (ATT) is supplemented with adipose-derived stem cells (ADSCs) to improve the efficient grafting in the correction of soft tissue defects. MSC-like cells may also be used in tumor-targeted cell therapy. However, MSC may have adverse effects on sarcoma development. In the present study, human ADSCs, MSCs and pre-osteoclasts were co-injected with human MNNG-HOS osteosarcoma cells in immunodeficient mice. ADSCs and MSCs, but not the osteoclast precursors, accelerated the local proliferation of MNNG-HOS osteosarcoma cells. However, the osteolysis and the metastasis process were not exacerbated by ADSCs, MSCs, or pre-osteoclasts. In vitro proliferation of MNNG-HOS and Saos-2 osteosarcoma cells was increased up to 2-fold in the presence of ADSC-conditioned medium. In contrast, ADSC-conditioned medium did not change the dormant, quiescent state of osteosarcoma cells cultured in oncospheres. Due to the enhancing effect of ADSCs/MSCs on in vivo/in vitro proliferation of osteosarcoma cells, MSCs may not be good candidates for osteosarcoma-targeted cell therapy. Although conditioned medium of ADSCs accelerated the cell cycle of proliferating osteosarcoma cells, it did not change the quiescent state of dormant osteosarcoma cells, indicating that ADSC-secreted factors may not be involved in the risk of local recurrence. PMID:26998421

  13. Towards a Taenia solium Cysticercosis Vaccine: an Epitope Shared by Taenia crassiceps and Taenia solium Protects Mice against Experimental Cysticercosis

    Science.gov (United States)

    Toledo, Andrea; Larralde, Carlos; Fragoso, Gladis; Gevorkian, Goar; Manoutcharian, Karen; Hernández, Marisela; Acero, Gonzalo; Rosas, Gabriela; López-Casillas, Fernando; Garfias, Carlos Kubli; Vázquez, Ricardo; Terrazas, Ignacio; Sciutto, Edda

    1999-01-01

    The Taenia crassiceps recombinant antigen KETc7 has been shown to be effective as a vaccine against experimental murine cysticercosis, a laboratory model used to test potentially promising molecules against porcine Taenia solium cysticercosis. Based on the deduced amino acid sequence of this proline-rich polypeptide, three fragments, GK-1, GK-2, and GK-3, were chemically synthesized in linear form. Of the three peptides, only GK-1 induced sterile protection against T. crassiceps cysticercosis in 40 to 70% of BALB/cAnN male mice. GK-1 is an 18-amino-acid peptide which contains at least one B-cell epitope, as demonstrated by its ability to induce an antibody response to the peptide and T. crassiceps antigen without need of a carrier protein. Immunofluorescence studies revealed that anti-GK1 antibodies strongly react with the native protein in the tegument of T. crassiceps and also with anatomical structures of T. solium eggs, oncospheres, cysticercus, and tapeworm. GK-1 also contains at least one T-cell epitope, capable of stimulating the proliferation of CD8+ and to a lower extent CD4+ T cells primed either with the free peptide or T. crassiceps total antigen. The supernatant of the stimulated cells contained high levels of gamma interferon and low levels of interleukin-4. Similar results were obtained with T cells tested for intracellular cytokine production, an indication of the peptide’s capacity to induce an inflammatory response. The remarkable protection induced by GK-1 immunization, its physicochemical properties, and its presence in all developmental stages of T. solium point to this synthetic peptide as a strong candidate in the construction of a synthetic vaccine against T. solium pig cysticercosis. PMID:10225916

  14. Chinchilla laniger can be used as an experimental model for Taenia solium taeniasis.

    Science.gov (United States)

    Maravilla, Pablo; Garza-Rodriguez, Adriana; Gomez-Diaz, Benjamin; Jimenez-Gonzalez, Diego Emiliano; Toral-Bastida, Elizabeth; Martinez-Ocaña, Joel; West, Brett; Molina, Nadia; Garcia-Cortes, Ramon; Kawa-Karasik, Simon; Romero-Valdovinos, Mirza; Avila-Ramirez, Guillermina; Flisser, Ana

    2011-12-01

    Chinchilla laniger has been reported as an experimental definitive host for Taenia solium; however no information about its suitability and yield of gravid tapeworm proglottids containing viable and infective eggs has been published. In total 55 outbred female chinchillas were infected with 4 cysticerci each; hosts were immunodeppressed with 6 or 8 mg of methyl-prednisolone acetate every 14 days starting the day of infection and their discomfort was followed. Kinetics of coproantigen ELISA or expelled proglottids was used to define the infection status. Efficiency of tapeworm establishment was 21% and of parasite gravidity was 8%; chinchillas showed some degree of suffering along the infection. Viability of eggs obtained from gravid proglottids was tested comparing methods previously published, our results showed 62% viability with propidium iodide, 54% with trypan blue, 34% with neutral red, 30% by oncosphere activation and 7% with bromide 3-(4,5-dimetil-tiazol-2-il)-2,5-difenil-tetrazolio (MTT) reduction; no statistical differences were obtained between most techniques, except activation. Four piglets were infected with 50,000 eggs each, necropsy was performed 3 months later and, after counting the number of cysticerci recovered, the percentage of infection was similar to data obtained with T. solium eggs recovered from humans. Our results demonstrate that the experimental model of T. solium taeniasis in C. laniger is a good alternative for providing eggs and adult tapeworms to be used in different types of experiments; optimization of the model probably depends on the use of inbred hosts and on the reduction of infected animals' suffering.

  15. Tapeworms.

    Science.gov (United States)

    Georgi, J R

    1987-11-01

    Dogs and cats become infected with tapeworms by ingesting intermediate hosts that contain encysted juvenile tapeworms called larvae. The dog or cat is said to be the definitive host because it shelters the sexually reproductive, egg-producing stage of the tapeworm. The intermediate hosts, which are vertebrates in the case of Taenia and Mesocestoides and insects in the case of Dipylidium and Hymenolepis, become infected by ingesting unhatched but infective tapeworm eggs discharged in the feces of the dog or cat. The relatively less common Diphyllobothrium and Spirometra tapeworms discharge eggs that are undeveloped when passed in the feces and must fall into water to undergo development to the coracidium stage. Diphyllobothrium and Spirometra may have two or three aquatic intermediate hosts in series. The first of these, a copepod, ingests the free-swimming coracidium or ciliated oncosphere that has hatched from the egg. The final intermediate host containing the larva (plerocercoid) infective for the dog or cat is an aquatic vertebrate (fish, frog, water snake). Thus, dogs and cats become infected with tapeworms by eating uncooked meat or fish or by ingesting certain insects. These intermediate hosts are infected with juvenile tapeworms called larvae, which are the infective form for the dog or cat. The intermediate hosts, in turn, become infected by ingesting tapeworm eggs discharged in the feces of the dog or cat or, in the case of Diphyllobothrium and Spirometra, by ingesting coracidia that have subsequently developed in and hatched from such eggs. By far the most common tapeworms of dogs and cats in North America are D. caninum, T. pisiformis, and T. hydatigena. Therefore, the most common sources of tapeworm infection are, respectively, fleas, wild rabbits, and the uncooked meat and offal of ruminants and swine. Whenever a dose of tapeworm remedy is administered or dispensed, the client should be informed of these potential sources of reinfection. There is

  16. Neurocysticercosis.

    Science.gov (United States)

    Del Brutto, Oscar H

    2014-01-01

    Known as a disease of swine in ancient civilizations, cysticercosis is currently considered the most common helminthic infection of the nervous system, and a leading cause of acquired epilepsy worldwide. The disease occurs when humans become intermediate hosts of the tapeworm Taenia solium by ingesting its eggs from contaminated food or, most often, directly from a Taenia carrier by the fecal-oral route. Once in the human intestine, Taenia eggs evolve to oncospheres that, in turn, cross the intestinal wall and lodge in human tissues - especially the nervous system - where cysticerci develop. The brain is a hostile environment in which parasites attempt to escape the immune surveillance while the host is trying to drive out the infection. In some cases, cysticerci are destroyed by this immunological attack, while in others, parasites may live unchanged for years. Cysticerci may be located in brain parenchyma, subarachnoid space, ventricular system, or spinal cord, causing a myriad of pathologic changes that are the main changes responsible for the clinical pleomorphism of neurocysticercosis. Seizures are the most common clinical manifestation of the disease, but some patients present with focal deficits, intracranial hypertension, or cognitive decline. With the exception of cystic lesions showing the scolex as an eccentric nodule, neuroimaging findings of neurocysticercosis are nonspecific and may be seen in other diseases of the nervous system. Likewise, immune diagnostic tests have been faced with problems related to poor sensitivity or specificity. Accurate diagnosis is possible after interpretation of clinical data together with findings of neuroimaging studies and results of immunologic tests, in a proper epidemiologic scenario. The introduction of cysticidal drugs has changed the prognosis of neurocysticercosis. Praziquantel and albendazole have been shown to reduce the burden of infection in the brain (as seen on neuroimaging studies) and to improve the

  17. TSOL18 Vaccine Antigen of Taenia solium: Development of Monoclonal Antibodies and Field Testing of the Vaccine in Cameroon

    Directory of Open Access Journals (Sweden)

    Assana, E.

    2010-01-01

    Full Text Available Chapter 1 reviews the literature about the immunological aspects of taeniid cestode infections and the existing vaccines against Taenia solium cysticercosis in pigs. One of the most promising vaccines is TSOL18, a protein that has been identified in the oncosphere of Taenia solium and expressed as a recombinant molecule in E. coli. Repeated experimental trials have shown that this vaccine is able to protect up to 100% of the immunised pigs against a challenge infection with T. solium. Antibodies raised by the vaccine are capable of killing the parasite in in vitro cultures and it is believed that antibody and complement mediated killing of invading parasites is the major protective immune mechanism induced by vaccination with TSOL18. The identification of the villages with a high risk of T. solium infection, which could subsequently be used in the vaccine trial, is reported in chapter 2. A survey was conducted in 150 households owning 1756 pigs in the rural areas of Mayo-Danay division in the far north region of Cameroon. A questionnaire survey was carried out to collect information on the pig farming system and to identify potential risk factors for T. solium cysticercosis infection in pigs. Blood samples were collected from 398 pigs with the aim of estimating the sero-prevalence of Taenia solium cysticercosis. The results showed that 90.7% of the pigs were free roaming during the dry season and that 42.7% of households keeping pigs in the rural areas had no latrine facility. Seventy six percent of the interviewed pig owners affirmed that the members of the household used open field defecation. ELISA for antigen and antibody detection showed an apparent prevalence of porcine cysticercosis of 24.6% and 32.2%, respectively. A Bayesian approach using the conditional dependence between the two diagnostic tests indicated that the true sero-prevalence of cysticercosis in Mayo-Danay was 26.6%. Binary logistic regression analysis indicated that the

  18. 豆状带绦虫TPO18基因的原核表达及保护性分析%Prokaryotic Expression and Protective Efficacy of TPO18 Gene fromTaenia pisiformis

    Institute of Scientific and Technical Information of China (English)

    韩进欢; 苟惠天; 尚清炎; 孙晓林

    2014-01-01

    病的高效疫苗。%[Objective]The study aimed to investigate the protective efficacy of the recombinant antigen of TPO18 (pGEX-TPO18) from Taenia pisiformis.[Method] Total RNA was extracted from oncosphere ofT. pisiformis. A pair of primers was designed based on the conserved region of other Taeniidae 18 kD gene.TheEcoR I andXho I restriction sites were introduced into 5′ end ofprimers. After RT-PCR, amplification product was cloned into pMD18-T, sequenced and the sequence analysis was made with bioinformatics. The products were ligated into the pGEX-4T-1 vector after digestion withEcoRⅠ+XhoⅠ and purified. The recombinant pGEX-TPO18 plasmid was transformed intoE. coli BL21 and spots were picked after shaking bacteria. The correctly identified recombinant plasmid, identified by PCR and sequenced, was named pGEX-TPO18. The recombinant plasmids were induced for expression with IPTG, cells were collected by SDS-PAGE analysis and purified using GST agarose resin. Then, TPO18 protein was detected by Western blotting. Rabbits were immunized with the purified recombinant protein emulsified with Freund’s adjuvant, 206 adjuvant, Al(OH)3 adjuvant, respectively, and rabbit anti-TPO18 serum was prepared. Each rabbit was injected with 50μg recombinant protein for 3 times. On the 34th day after final inoculation, each rabbit was challenged by 1 500 eggs ofT. pisiformis. On the 58th day after infection, rabbits were sacrificed and the number of cysts was counted. Before and after 7 days of every immunization, serum was separated. And serum antibody levels were detected using ELISA assay with 40 µg·mL-1 recombinant protein-coated microtiter plates, 1﹕200 dilution of serum and detection of the OD492nm value of serum samples was made.[Result] The product of RT-PCR was 339 bp and agree with expectations; The results of sequencing showed no mutation. So, the construction of recombinant plasmid pGEX-TPO18 was successful. The pGEX-TPO18 was transformed intoE. coliBL21. SDS-PAGE showed that the 38.6 kD fusion