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1.
Afr. J. Clin. Exp. Microbiol ; 20(3): 254-259, 2019. tab
Article in English | AIM (Africa) | ID: biblio-1256082

ABSTRACT

Background: The Kato-Katz technique is recommended for diagnosis of Schistosoma mansoni infection by the World Health Organization. However, egg counts are subject to variability. The aim of this study is to determine the prevalence of S. mansoni infection in school children using two different techniques and to recommend the technique that should be routinely used in the diagnosis of this infection. Methodology: Field investigations on faecal samples from 299 Cameroonian school children were carried out in 2016 to compare the effectiveness of the Kato-Katz and Formalin-ether techniques in diagnosis of S. mansoni infections. Results: Schistosome eggs were detected in 37 (12.3%) samples with the Kato-Katz technique and 61 (20.4%) samples with the Formalin-ether technique. The difference between the prevalence observed for the two techniques was significant in males and age group 10 - 12 years (p < 0.5). Conclusion: The Formalin-ether technique was more sensitive than the Kato-Katz method for detecting S. mansoni eggs in faecal matter. Despite its cost, the Formalin-ether technique can be routinely used in the laboratory for epidemiological studies of intestinal schistosomiasis


Subject(s)
Cameroon , Child , Infections , Schistosoma mansoni , Schistosoma mansoni/analysis , Schools
2.
Rev. Inst. Med. Trop. Säo Paulo ; 37(4): 325-9, jul.-ago. 1995. ilus, tab
Article in English | LILACS | ID: lil-159105

ABSTRACT

Atraves da analise de exames parasitologicos quantitativos seriados e da contagem de esquistossomos apos perfusao em dois grupos de camundongos infectados com diferentes cargas de cercarias de Schistosoma mansoni, verificou-se a existencia da estabilidade da eliminacao de ovos e sua correlacao com a carga parasitaria na fase inicial da esquistossomose mansoni...


Subject(s)
Animals , Female , Mice , Feces/parasitology , Parasite Egg Count , Schistosoma mansoni/analysis , Schistosoma mansoni/pathogenicity , Schistosomiasis mansoni/pathology
3.
Mem. Inst. Oswaldo Cruz ; 87(supl.4): 67-70, 1992. ilus
Article in English | LILACS | ID: lil-125628

ABSTRACT

Protein extracts obtained from male and female shistosomes were incubated with a gender-specific gene, F-10, transcribed only in adult females and encoding a major egg-shell protein. The protein/DNA interaction was measured using the band shift, DNase-I-footprinting and UV cross-linking techniques. The results showed a clear band shift when a 302 bp restriction fragment containing the 3'end of the gene was incubated with either female or male proteins. This fragment also contained a putative steroid hormone regulatory element (HRE). In contrast, only the male proteins produced a shift with the 495 bp fragment corresponding to the middle region of the gene. DNase I footprinting showed that proteins from males and females interacted with the F-10 gene by binding to multiple adjacent sites along the DNA, thus generatingrelatively long protected fragments of approximately 100 bp. This result suggested that the adjacent binding of several moles of proteins occured at the 5'end of the gene. UV cross-linking between schistosome proteins and a 21 bp synthetic oligonucleotide the F-10 HRE, evidence proteins having MWS of 30,45 and 65 kDNA. These proteins are presumably involved in the regulation of transcription of the F-10 gene


Subject(s)
Bacterial Proteins , Schistosoma mansoni/analysis , Sexual Maturation
4.
J Helminthol ; 65(2): 89-94, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1908874

ABSTRACT

The existence of adult Schistosoma haematobium worm proteins (Sh31/32) homologous to the diagnostic Sm31/32 of S. mansoni is shown. Sm31/32 and Sh31/32, adsorbed on nitrocellulose and kept dry on the bench before immunoblot analysis, were antigenically stable for at least 4 years including storage for 17 months in tropical climates. The antigens react with patient sera in the absence of defined buffers under rather simple conditions ("humid chamber blot"). The results add to the use of these antigens for serodiagnosis of schistosomiasis in endemic areas.


Subject(s)
Antigens, Helminth/immunology , Helminth Proteins/immunology , Schistosoma haematobium/analysis , Schistosoma mansoni/analysis , Animals , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Haplorhini , Humans , Hydrolysis , Immune Sera/immunology , Molecular Weight , Schistosoma haematobium/immunology , Schistosoma mansoni/immunology , Schistosomiasis haematobia/diagnosis , Schistosomiasis mansoni/diagnosis , Tropical Climate
5.
J Parasitol ; 77(3): 391-401, 1991 Jun.
Article in English | MEDLINE | ID: mdl-1710270

ABSTRACT

A major 50-kDa soybean agglutinin (SBA)-reactive component present in extracts of Schistosoma mansoni eggs was isolated by SBA lectin affinity chromatography. In polyacrylamide gel electrophoresis (PAGE), the SBA-reactive component was seen as a 100-kDa polypeptide band that after reduction and alcylation was substituted by a 50-kDa component. This suggests that it occurs in native form as a dimer. Monoclonal antibodies produced against gp50 reacted with miracidial and cercarial secretions and with adult worm components including tegumental structures suggestive of a secretory function.


Subject(s)
Glycoproteins/isolation & purification , Helminth Proteins/isolation & purification , Plant Lectins , Schistosoma mansoni/analysis , Schistosomiasis mansoni/parasitology , Soybean Proteins , Animals , Antibodies, Monoclonal/immunology , Chromatography, Affinity , Electrophoresis, Polyacrylamide Gel , Epitopes/analysis , Female , Glycoproteins/chemistry , Glycoproteins/immunology , Helminth Proteins/chemistry , Helminth Proteins/immunology , Lectins , Liver/parasitology , Male , Microscopy, Fluorescence , Schistosoma mansoni/growth & development , Schistosoma mansoni/immunology
6.
Anal Biochem ; 194(2): 237-42, 1991 May 01.
Article in English | MEDLINE | ID: mdl-1713748

ABSTRACT

Proteins in which some or all of the tyrosine side chains are post-translationally modified to dihydroxyphenylalanine have been found in several invertebrate phyla. In this paper we describe the unusual silver-staining properties of these 3,4-dihydroxyphenylalanine (Dopa)-proteins in silver-stained polyacrylamide gels. Our evidence suggests that the rapid silver staining of these proteins is due to the 3,4-dihydroxyphenol ring which is a highly effective reducing agent in the alkaline development conditions used in the final step of most silver-staining procedures. Normal proteins comprising the standard 20 amino acids and tyrosine on its own, do not reduce silver under these conditions. Pretreatment of the gels with acid-dichromate solutions abrogates the rapid staining of the Dopa-proteins. This rapid silver-staining technique will facilitate the rapid screening of many additional organisms for Dopa-proteins using sodium dodecyl sulfate gels and small amounts of tissue.


Subject(s)
Dihydroxyphenylalanine/analysis , Electrophoresis, Polyacrylamide Gel/methods , Helminth Proteins/chemistry , Schistosoma mansoni/analysis , Animals , Female , Kinetics , Male , Mice , Mice, Inbred BALB C , Protein Processing, Post-Translational , Silver , Staining and Labeling
7.
J Parasitol ; 77(2): 263-71, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2010859

ABSTRACT

The proteins released in vitro by metabolically radiolabeled adult Schistosoma mansoni were identified by 2-dimensional gel electrophoresis. To determine the origin of these proteins, adult worms were fractionated into surface membrane, tegument, and remaining body components, and the electrophoretic patterns of the proteins in the 3 fractions were compared to those of the released proteins. The immunogens present in these fractions then were identified by immunoprecipitation with sera from humans infected with S. mansoni. This analysis indicated that essentially all of the proteins released from the worm were immunogenic, whereas most of the major membrane and tegumental proteins were not reactive with the immune sera. Thus, it appears that the adult worm is defended against immune attack by detection of the host's antibody response against released proteins rather than against proteins-exposed on the worm's surface.


Subject(s)
Antigens, Helminth/analysis , Helminth Proteins/immunology , Schistosoma mansoni/immunology , Animals , Antigens, Surface/analysis , Chemical Fractionation , Electrophoresis, Gel, Two-Dimensional , Electrophoresis, Polyacrylamide Gel , Helminth Proteins/analysis , Humans , Male , Microscopy, Electron , Precipitin Tests , Schistosoma mansoni/analysis , Schistosoma mansoni/ultrastructure
8.
Exp Parasitol ; 72(1): 63-8, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1847106

ABSTRACT

Calcium-binding proteins (CaBPs) of Schistosoma mansoni were purified by hydrophobic affinity chromatography. Metabolically labeled CaBPs were characterized using SDS-polyacrylamide gel electrophoresis followed by fluorography. A number of CaBPs were detected in total tissue extracts, apical plasma membrane, and soluble fractions of the apical bilayer complex, ranging from 15 to 205 kDa in their molecular masses. No CaBPs were discerned in the envelope of the apical bilayer complex. Two CaBPs were positively identified as calmodulin and gelsolin via immunoblot analyses. The possible role of CaBPs in surface signal transduction mechanisms has also been briefly discussed.


Subject(s)
Calcium-Binding Proteins/analysis , Schistosoma mansoni/analysis , Animals , Blotting, Western , Calcium-Binding Proteins/chemistry , Calcium-Binding Proteins/isolation & purification , Calmodulin/analysis , Calmodulin/chemistry , Calmodulin/isolation & purification , Cell Membrane/chemistry , Cross Reactions , Electrophoresis, Polyacrylamide Gel , Gelsolin , Microfilament Proteins/analysis , Microfilament Proteins/chemistry , Microfilament Proteins/isolation & purification , Molecular Weight , Schistosoma mansoni/ultrastructure , Signal Transduction
9.
Int J Parasitol ; 20(8): 1091-3, 1990 Dec.
Article in English | MEDLINE | ID: mdl-2074137

ABSTRACT

Glycolipid patterns of cercarial and adult Schistosoma mansoni were determined and compared with those of Biomphalaria glabrata snails and mouse (BALB/c strain) red blood cells by high-performance thin-layer chromatography. Differences in glycolipid content were found between cercariae and adult worms and between these stages and their respective host tissues.


Subject(s)
Biomphalaria/analysis , Erythrocytes/chemistry , Glycolipids/analysis , Schistosoma mansoni/analysis , Animals , Chromatography, Thin Layer , Glycolipids/blood , Mice , Mice, Inbred BALB C
10.
Mol Biochem Parasitol ; 43(2): 245-55, 1990 Dec.
Article in English | MEDLINE | ID: mdl-2090946

ABSTRACT

Molecular mimicry has been considered as a possible way for parasites to escape host immune responses. This work concerns the characterization of protein determinants shared by Schistosoma mansoni and its intermediate host Biomphalaria glabrata. Parasite (Sm39) and mollusc (Bg 39) cross-reactive proteins were identified and shown to induce in rabbit and mouse, antibodies specific for invertebrate determinants. Ultrastructural studies demonstrated that antibodies to Sm39 specifically bound to muscular structures of parasite and mollusc. Molecular cloning and sequencing indicated that Bg39 corresponded to a muscular isoform of tropomyosin. The mollusc sequence showed a 51-65% homology with seven different muscular tropomyosins from vertebrate and invertebrate species. The highest score of homology was observed with S. mansoni tropomyosin, suggesting that cross-reactive determinants could be specific for the trematode and its intermediate host. In miracidia, Sm39 epitopes were also shown to be contained in the vesicles present in epidermal ridges and cellular bodies. Such vesicles are involved in the formation of a protective tegument around sporocysts, suggesting a possible role of cross-reactive tropomyosins in miracidia and/or sporocyst-snail interactions.


Subject(s)
Biomphalaria/analysis , Schistosoma mansoni/analysis , Tropomyosin/chemistry , Amino Acid Sequence , Animals , Biomphalaria/immunology , Biomphalaria/parasitology , Blotting, Northern , Cloning, Molecular , Cross Reactions , Host-Parasite Interactions , Immunohistochemistry , Molecular Sequence Data , Schistosoma mansoni/growth & development , Schistosoma mansoni/immunology , Sequence Homology, Nucleic Acid , Tropomyosin/immunology
11.
Parasitology ; 101 Pt 2: 227-34, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2263417

ABSTRACT

The localization and distribution of the serotoninergic and peptidergic elements of the nervous system of larval Schistosoma mansoni have been investigated using an indirect immunofluorescence technique in conjunction with confocal scanning laser microscopy (CSLM). A range of antisera was used, raised to the biogenic amine, 5-hydroxytryptamine (5-HT, or serotonin), the vertebrate peptides pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY) and to the native invertebrate peptide, FMRFamide; all these antisera were shown previously to be immunopositive in the adult worm. No immunoreactivity to 5-HT was detected in any of the larval stages, but both miracidia and cercariae were consistently immunoreactive to all 4 peptides. The peptidergic nervous system of the miracidium is relatively simple, taking the form of a central neural mass with associated paired anterior and posterior nerve tracts. The cercarial peptidergic nervous system comprises a central commissure joining paired anterior ganglia, from which emanate paired dorsal and ventral nerve tracts, which terminate at the body/tail junction. The excretory bladder region of the tail is also immunoreactive for the 4 peptides, and a fine pair of nerve tracts extends the length of the tail shaft. Immunoreactive nerve cell bodies are also evident in the midbody region of the intrasprocystic cercariae, these same structures being immunoreactive for the neuronal marker, neurone-specific enolase (NSE). The organization of the larval peptidergic nervous system is compared to that of the cholinergic nervous system and contrasted with the peptidergic system in the adult worm. The absence of immunoreactivity to 5-HT is discussed in relation to the proposed development of the aminergic nervous system upon establishment in the definitive host.


Subject(s)
Neuropeptides/analysis , Schistosoma mansoni/anatomy & histology , Serotonin/analysis , Animals , Fluorescent Antibody Technique , Immunoenzyme Techniques , Immunohistochemistry , Larva/anatomy & histology , Lasers , Nervous System/anatomy & histology , Nervous System/chemistry , Schistosoma mansoni/analysis
12.
Cell Tissue Res ; 261(3): 573-81, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2245454

ABSTRACT

The presence and distribution of neuropeptides belonging to the pancreatic polypeptide family have been demonstrated by an indirect immunofluorescence technique in the nervous systems of adult male and female Schistosoma mansoni. Seven antisera of differing regional specificity to pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY) were employed on both whole-mount and cryostat-sectioned material. Positive immunoreactivity (IR) was obtained with all antisera except an N-terminally-directed antiserum to NPY. In the CNS, immunoreactivity was restricted to cell bodies and nerve fibres in the anterior ganglia, central commissure and dorsal and ventral nerve cords of both sexes, whereas, in the PNS, positive-IR was present in the plexuses innervating the subtegumental musculature and the oral and ventral suckers. Intense immunoreactivity was observed in a plexus of nerve fibres and cell bodies in the lining of the gynaecophoric canal and in fine nerve fibres innervating the dorsal tubercles of the male. In contrast, in the female, strong immunoreactivity was evident in nerve plexuses innervating the lining of the ovovitelline duct and in the wall of the ootype, but most notably in a cluster of cells in the region of Mehlis' gland. Results suggest that molecules with C-terminal homology to the PP-family are present in S. mansoni. These peptides would appear to be important regulatory molecules in the parasite's nervous system and may play a role in the control of egg production.


Subject(s)
Pancreatic Polypeptide/analysis , Schistosoma mansoni/analysis , Animals , Central Nervous System/chemistry , Female , Male , Neuropeptide Y/analysis , Peptide YY , Peptides/analysis , Schistosoma mansoni/cytology
13.
J Parasitol ; 76(4): 601-5, 1990 Aug.
Article in English | MEDLINE | ID: mdl-2199654

ABSTRACT

Studies on schistosome protective immune responses have focused mainly on antigens of the parasite's syncytial surface. One of the characterized schistosome antigens, a 24-kDa glycoprotein, has been considered important in mechanisms of immune evasion by the parasites. In the present study, using affinity-purified antibodies to the 24-kDa protein for immunofluorescence and immunoelectron microscopy, we demonstrated an association of the 24-kDa antigen with the discoid bodies (the major syncytial inclusion bodies; DBs) and the surface membrane complex (most likely the apical plasma membrane) of adult Schistosoma mansoni. This is consistent with previous observations that the 24-kDa antigen appeared to be localized to the syncytial membrane and DB fractions. The present results also support the suggestion that the DBs are the precursor organelles of the apical plasma membrane.


Subject(s)
Antigens, Helminth/analysis , Glycoproteins/analysis , Schistosoma mansoni/analysis , Animals , Antibodies, Helminth/immunology , Antibodies, Helminth/isolation & purification , Blotting, Western , Fluorescent Antibody Technique , Immunohistochemistry , Microscopy, Electron , Schistosoma mansoni/immunology , Schistosoma mansoni/ultrastructure
14.
Int J Parasitol ; 20(3): 279-84, 1990 May.
Article in English | MEDLINE | ID: mdl-2358310

ABSTRACT

Antisera to vertebrate actin and actin-binding proteins were used to characterize the cytoskeleton of adult Schistosoma mansoni. Actin, alpha-actinin and tropomyosin immunoreactivities were detected in the cytoplasm of the apical tegument. Antiserum to alpha-actinin bound to the tegumental spines and this protein may be involved in cross-linking of spine actin filaments. Actin, alpha-actinin and tropomyosin antisera bound to the musculature. Strongest immunoreactivity was seen in the parenchyma. Antisera to actin, alpha-actinin, tropomyosin and spectrin bound to parenchyma cells including those of the tubercles, suggesting that these proteins are located in muscle cell bodies. The distribution of cytoskeletal proteins is discussed in relation to tegumental repair processes.


Subject(s)
Cytoskeletal Proteins/analysis , Helminth Proteins/analysis , Schistosoma mansoni/analysis , Animals , Immunohistochemistry , Male
15.
Parasitology ; 100 Pt 1: 19-28, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2107504

ABSTRACT

Cyclosporin A administered to Schistosoma mansoni-infected mice at around day 20 of infection reduces the worm burden by greater than 60%, as assessed by portal perfusion on days 28 and 86. Those worms recovered at perfusion have been examined by light and electron microscopy for drug-induced changes in morphology. Gross parasite damage was characterized by massive bolus formation and subsequent herniation of the gut. This event was attributed to the abnormal accumulation of crystalline structures in the lumen; the crystals were closely associated with lipid droplets, and were shown by X-ray micro-analysis to contain iron. Such crystals were seen only rarely in the intestines of control worms, but they too gave small iron peaks when examined by X-ray micro-analysis. In some drug-treated worms the caecal epithelium had ruptured, thereby releasing luminal contents throughout the worm body. In addition, herniations of the gut were seen protruding through the tegument causing surface deformation and disruption of tegumental and parenchymal tissues. The structural integrity of the worm was ultimately compromised allowing access to cytotoxic effector cells of the host. The combined effects of drug action and cellular cytotoxicity presumably account for the very significant levels of worm killing achieved by CsA treatment of the host.


Subject(s)
Cyclosporins/therapeutic use , Schistosoma mansoni/drug effects , Schistosomiasis mansoni/drug therapy , Animals , Cyclosporins/pharmacology , Electron Probe Microanalysis , Female , Iron/analysis , Male , Mice , Mice, Inbred BALB C , Microscopy, Electron , Microscopy, Electron, Scanning , Schistosoma mansoni/analysis , Schistosoma mansoni/ultrastructure , Schistosomiasis mansoni/parasitology
16.
Parasitol Res ; 76(5): 435-9, 1990.
Article in English | MEDLINE | ID: mdl-2352921

ABSTRACT

Incubation of the adult Schistosoma mansoni with the anti-schistosomal compound oltipraz (OPZ) (40 nM) resulted in a significant decrease in schistosome-reduced glutathione (GSH), a thiol compound which may have a role in protection against oxidant-mediated damage. A significant proportion (20-47%) of worms treated with OPZ became susceptible to in vitro killing by zymosan-stimulated peritoneal exudate cells from mice infected with S. mansoni or inoculated with Bacillus Calmette Guérin (BCG). Killing of the worms was partially inhibited by the addition to the assay system of exogenous glutathione peroxidase with GSH but not by superoxide dismutase. These results suggested that killing of parasites exposed to the drug was partly mediated by cell-generated hydrogen peroxide. They indicate also that depletion of schistosome GSH levels could render the parasites susceptible to killing by oxidative mechanisms, and suggest that there is potential in exploiting schistosome oxidant defense systems and reactive oxygen byproducts in the treatment of schistosomiasis. Inhibition of schistosome oxidant defense systems with drugs may render the parasites susceptible to killing by reactive oxygen byproducts of effector cells.


Subject(s)
Phagocytes/immunology , Pyrazines/pharmacology , Schistosoma mansoni/drug effects , Schistosomicides/pharmacology , Animals , Glutathione/analysis , Immunity, Cellular/drug effects , Mice , Mice, Inbred C57BL , Oxidation-Reduction , Peritoneal Cavity/cytology , Schistosoma mansoni/analysis , Schistosoma mansoni/immunology , Thiones , Thiophenes
17.
Exp Parasitol ; 69(4): 373-92, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2806461

ABSTRACT

We have defined the polypeptide pattern of 3-hr Schistosoma mansoni schistosomula on nonequilibrium two-dimensional gels (NEPHGE). An acidic group of polypeptides with a molecular weight of about 40 kDa and a pI value of around 5.0 (numbered 48/59/53) were identified as antigens on Western blots probed with chronic human infection sera or vaccinated mouse sera. Polypeptides 48/49/53 from silver-stained NEPHGE gels produced antisera that were specific as demonstrated by Western blot analysis and immunoprecipitations of in vitro translation products. A cDNA clone (clone 1) from a S. mansoni adult worm pBR322 library was isolated by using cDNA probes made from size-fractionated mRNA and defined as encoding polypeptide 49 by hybridization selection of the mRNA which was in vitro translated and immunoprecipitated with specific mouse antiserum. A lambda gt 11 expression clone which contained an insert close to the full length mRNA was isolated from a S. mansoni cercariae library. The complete sequence of the mRNA was determined by sequencing the insert of this clone as well as primer extension of total RNA. The only open reading frame coding for 284 amino acids in the 1316 nucleotide sequence showed a 44.76 to 55.44% homology with the amino acid sequences of 18 different tropomyosins from various species. Computer-predicted secondary structure of schistosome tropomyosin was mainly alpha-helix which was very similar to other tropomyosins. Northern analysis showed the mRNA to be about 1.5 kb in size and detectable at much higher levels in the adult worm stage as compared to the cercariae and the egg stages. Western blot analysis likewise showed that greater amounts of tropomyosin were detected in extracts from adult worm stage as compared to extracts from cercariae and egg stages. Immunocytochemical analysis shows that tropomyosin is strongly associated with the tegument of adult worms. The restriction digestion pattern given by genomic Southern analysis suggests the existence of introns and/or multiple gene copies. Thus polypeptide 49, an immunodominant antigen, represents schistosome tropomyosin.


Subject(s)
Antigens, Helminth/genetics , DNA/genetics , Schistosoma mansoni/genetics , Tropomyosin/genetics , Amino Acid Sequence , Animals , Antigens, Helminth/analysis , Base Sequence , Blotting, Western , Enzyme-Linked Immunosorbent Assay , Molecular Sequence Data , Peptides/analysis , Peptides/immunology , Protein Conformation , RNA, Messenger/genetics , Schistosoma mansoni/analysis , Schistosoma mansoni/growth & development , Schistosoma mansoni/immunology , Sequence Homology, Nucleic Acid , Tropomyosin/analysis , Tropomyosin/immunology
18.
Exp Parasitol ; 69(3): 249-62, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2507344

ABSTRACT

Schistosomula proteins separated by a two-dimensional (NEPHGE) gel system identify 94 major silver-stained polypeptides. When compared to polypeptides similarly separated from cercariae and adult worms; cercariae share the same polypeptides as schistosomula, adult worms share ca. 60% of the polypeptides. A group of five schistosomula polypeptides 15-31 kDa (apparent pI 8.2-8.9) was not found in adult worm extracts. To identify which polypeptides were immunogens, Western blots of the NEPHGE gels were probed with sera either from humans with chronic schistosomiasis or from mice vaccinated with irradiated cercariae. For characterization studies, polyclonal antibodies were made against the five schistosomula-specific and selected immunogenic polypeptides by immunizing mice with silver-stained spots removed from NEPHGE gels. We show that the polyclonal serum against a polypeptide of 12.5 kDa and an apparent pI of 6.70 mediated complement and eosinophil-dependent killing of schistosomula in an in vitro assay. Epitopes recognized by antibody against the 12.5-kDa polypeptide show a diffuse distribution and are found on flame cells of the excretory system of the schistosomula.


Subject(s)
Antigens, Helminth/isolation & purification , Peptides/isolation & purification , Schistosoma mansoni/analysis , Schistosomiasis mansoni/blood , Animals , Antibodies/isolation & purification , Blotting, Western , Cytotoxicity, Immunologic , Electrophoresis, Gel, Two-Dimensional/methods , Fluorescent Antibody Technique , Humans , Mice , Mice, Inbred BALB C , Molecular Weight , Schistosoma mansoni/immunology
19.
Mol Biochem Parasitol ; 36(1): 11-8, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2509906

ABSTRACT

Both the liver fluke Fasciola hepatica and the blood fluke Schistosoma mansoni have GTP-binding proteins which are part of the trans-membrane signalling system. These proteins require GTP in order to interact with the catalytic subunit of adenylate cyclase. The technique of immunoblotting was used in order to distinguish the GTP-binding proteins Gs, Gi, and Go. Immunoblotting was carried out using antisera prepared against peptides deduced from bovine cDNA clones specific for alpha or beta subunits of known G proteins. A 41-kDa Gs alpha has been identified in S. mansoni and a 42.5-kDa Gs alpha in F. hepatica. A 41-kDa Go alpha was found in both parasites. A 36-kDa G beta was identified in both parasites using antiserum made against bovine transducin.


Subject(s)
Fasciola hepatica/analysis , GTP-Binding Proteins/analysis , Schistosoma mansoni/analysis , Amino Acid Sequence , Animals , Brain/parasitology , DNA/immunology , Fasciola hepatica/genetics , Fasciola hepatica/immunology , Female , Immunoblotting/methods , Male , Mice , Molecular Weight , Schistosoma mansoni/genetics , Schistosoma mansoni/immunology , Transducin/immunology
20.
J Immunol ; 142(3): 979-84, 1989 Feb 01.
Article in English | MEDLINE | ID: mdl-2536417

ABSTRACT

Schistosomula of Schistosoma mansoni were examined for the presence of glycosylphosphatidylinositol (GPI) anchored surface membrane Ag. Parasites were surface iodinated and cultured in the presence or absence of a crude phospholipase C (PLC) preparation or phosphatidylinositol-specific PLC (PIPLC). Culture supernatants were then analyzed: 1) by centrifugation to ascertain which molecules released from the surface were soluble or contained in membrane vesicles; 2) by immunoprecipitation with antibodies specific for the "cross-reacting determinant," an epitope revealed on some GPI-anchored proteins only after cleavage of the diacylglycerol from the protein by PIPLC, and 3) by immunoprecipitation with immune mouse sera to establish co-identity with previously described, immunologically relevant surface Ag. By using these techniques, schistosomula were shown to possess three GPI-anchored surface Ag of m.w. 38,000, 32,000 and 18,000 which are spontaneously released from the surface of schistosomula in association with membrane, but remain insoluble until cleaved by PIPLC. All three molecules were recognized by antibodies from mice vaccinated with irradiated cercariae and/or chronically infected mice. Moreover, the m.w. 38,000 component was recognized by a previously described protective mAb (E.1). A major developmental modification appears to occur in the expression of these molecules because, by the same techniques, no GPI-anchored surface Ag were detectable on 7-day-old lung stage parasites. The finding that these important parasite immunogens are GPI-anchored and released from the surface of the parasite in membrane vesicles may, in part, explain why they elicit strong immune responses capable of damaging the schistosomulum tegument.


Subject(s)
Antigens, Helminth/isolation & purification , Antigens, Surface/isolation & purification , Glycolipids , Phosphatidylinositols , Schistosoma mansoni/immunology , Animals , Antibodies, Helminth , Antigens, Helminth/immunology , Antigens, Surface/immunology , Cross Reactions , Cross-Linking Reagents , Glycosylphosphatidylinositols , Mice , Mice, Inbred C57BL , Molecular Weight , Phosphatidylinositol Diacylglycerol-Lyase , Phosphoric Diester Hydrolases , Precipitin Tests , Schistosoma mansoni/analysis , Schistosoma mansoni/growth & development
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