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Teresa Gárate

Publications and source records attributed to Teresa Gárate.

15 recordsLinked to original sources
PubMed2006

Molecular cloning and characterisation of Ts8B1, Ts8B2 and Ts8B3, three new members of the Taenia solium metacestode 8 kDa diagnostic antigen family.

Antibody screening of a lambdaZAP-XR Taenia solium metacestode cDNA library yielded a clone (Ts8B1), with an insert of 345 bp, and an open reading frame of 258 bp, that coded for a protein with 85 amino acid residues. Alignment of the predicted amino acid sequence with sequences from SWISSPROT revealed an 88% identity with TcA5.5, a 10 kDa immunodiagnostic antigen of T. crassiceps, 75% identity with CyDA a T. solium metacestode antigen, 40-50% identity with several variants of the 8 kDa subunit of antigen B of Echinococcus spp. and with members of the T. solium metacestode 8 kDa antigen family. Two other Ts8B1 related molecules, Ts8B2 and Ts8B3, were identified in the metacestode cDNA library by PCR, coding for 85 and 66 amino acid polypeptides, respectively. Both Ts8B1 and Ts8B2 were characterized as E/S antigens through their subcellular localisation in the secretory membrane system when expressed in NRK cells. The three cDNA inserts were expressed, purified and probed in enzyme-linked immunosorbent assays (ELISA) with sera and cerebro-spinal fluid from patients with confirmed neurocysticercosis, and with sera from pigs infected with T. solium. The most promising antigen, Ts8B2, performed with a sensitivity of 96.8% and specificity of 93.1% in the detection of active NCC when using serum samples in the assay and performed similarly in the porcine system. The implications of these findings are discussed.

Animals↗
PubMed2006

Schistosoma mansoni: a diagnostic approach to detect acute schistosomiasis infection in a murine model by PCR.

Schistosomiasis represents an increasing problem in non-endemic areas, due to the growing number of immigrants and to tourists contracting this disease in "off-the-beaten-track" tourism. Acute schistosomiasis is not diagnosed early due to the lack of diagnostic tools that are sufficiently sensitive enough to detect the parasite during the first weeks of infection. We have developed a diagnostic approach based on the detection of parasite DNA by polymerase chain reaction (PCR) in urine, comparing the performance of this new approach with the two currently used schistosomiasis diagnostic tools (Kato-Katz and ELISA) and the PCR in stool samples. This comparison was done in a Schistosoma mansoni murine experimental model, which permits follow up of the parasite from the acute to the chronic stage of infection. Our results suggest that this new PCR-based approach could be useful for the detection of acute schistosomiasis in easy-to-handle clinical samples such the urine.

Acute Disease↗
PubMed2005

A recombinant enolase from Anisakis simplex is differentially recognized in natural human and mouse experimental infections.

A 1,963-bp cDNA was isolated from an Anisakis simplex cDNA library by immunoscreening with a hyperimmune rabbit serum raised against a crude extract of A. simplex L3 larvae. The open reading frame encodes a putative protein of 436 amino acid residues, which exhibits high similarity (70-80%) to enolase molecules from various other organisms, including helminth parasites. After subcloning and expression of the A. simplex cDNA in PGEX-4T-3, the resulting glutathione S-transferase fusion protein, purified by glutathione-Sepharose-4B chromatography, showed functional enolase activity. The immunogenicity of the recombinant A. simplex enolase was analyzed by immunoblotting using sera obtained from (a) mice immunized with crude extracts (CE) of A. simplex, or other nematode species, (b) mice immunized with excretory-secretory (ES) antigens from A. simplex, or (c) mice infected with L3 larvae by the intraperitoneal route. In addition, we used ELISA, to investigate the presence of IgG1 and IgE antibodies against this molecule in sera from patients infected with A. simplex. Mouse sera obtained after infection with L3 or raised against CE antigens, but not sera raised against ES antigens, showed strong reactivity with the recombinant A. simplex enolase. We also obtained good reactivity in Western blotting with sera from mice immunized with CE antigens from Ascaris suum and Toxocara canis, but not with sera from mice immunized with CE antigens from Trichuris muris, Trichinella spiralis or Hysterothylacium aduncum. In contrast to the experimental infections/immunizations in mice, we were unable to detect anti-enolase IgE antibodies in sera from human patients infected with A.simplex (15 sera), and the levels of anti-enolase IgG1 antibodies in these sera were low and apparently nonspecific. These results seem to indicate that, during natural infection in humans, A. simplex larvae do not offer sufficient antigenic stimulus to induce anti-enolase antibodies.

Animals↗
PubMed2005

Taenia solium: characterization of a small heat shock protein (Tsol-sHSP35.6) and its possible relevance to the diagnosis and pathogenesis of neurocysticercosis.

A cDNA encoding for a predicted small heat shock protein (sHSP), Tsol-sfISP35.6, has been isolated by antibody screening of a Taenia solium c-DNA library. The clone was a full-length sequence (1172 bp) with an open reading frame of 945 bp and encoded for a 314 amino acid protein with deduced molecular mass of 35.6 kDa, isoelectric point of 5.6 arid the characteristic HSP20/alpha-crystallin domain duplicated. It was highly conserved, with a high sequence similarity with other platyhelminth sHSPs. Western blot analysis, using serum from neurocysticercosis patients (NCC), indicated that the purified Tsol-sHSP35.6 expression product was immunogenic, while in indirect ELISA, using the purified Tsol-sHSP35.6 expression product as antigen and serum samples from pigs and humans, 80% of T. solium infected pigs and 84% of patients with active, or 71% of patients with inactive NCC were sero-positive. The possible relevance of Tsol-sHSP35.6 in the diagnosis and pathogenesis of NCC is discussed.

Amino Acid Sequence↗
PubMed2005

Oncospheral peptide-based ELISAs as potential seroepidemiological tools for Taenia solium cysticercosis/neurocysticercosis in Venezuela.

This study evaluates five synthetic peptides derived from four, potentially protective, Taenia saginata oncosphere molecules for the serodiagnosis of T. solium cysticercosis/neurocysticercosis in three distinct Venezuelan endemic regions. The peptides, all of which have been described previously, are designated HP6-3, Ts45W-1, Ts45W-5, Ts45S-10 and TEG-1. In clinically verified and seropositive hospital cases, combining the results of three of the individual peptide-based ELISAs (HP6-3, Ts45W-1 and Ts45W-5) afforded the best balance between sensitivity (85%) and specificity (83.5%), a significant improvement on the 63.6% specificity obtained with the routinely employed T. solium cyst-fluid-based ELISA. Similarly, in the seropositive Venezuelan endemic zone samples, 89.09% of Amerindians, 77.27% of symptomatic rural subjects and 67.83% of non-symptomatic rural subjects were also classed as seropositive by the combined peptide-based ELISAs. The profile of antibody recognition to individual peptides varied between the different groups of samples examined. The relevance of the above findings for the serology and prognosis of T. solium cysticercosis/neurocysticercosis in hospital- and field-based situations is discussed.

Animals↗
PubMed2004

[Application of the PCR-RFLP technique for the species-specific identification of nematodes involved in human anisakiasis].

BACKGROUND AND OBJECTIVE: We intended to develop a molecular test allowing a species-specific identification of the anisakid human parasite independently of its evolutive stage. MATERIAL AND METHOD: Anisakid larvae were obtained from fish destined to human consumption. In the PCR-RFLP test, the DNA corresponding to the ITS-1, 5.8S rRNA gene, ITS-2 and approximately 70 of the 28S rRNA gene region was amplified and a positive control was included. Products were digested with the endonuclease Taq I and subsequently sequenced. RESULTS: Different anisakids (Anisakis simplex/Hysterothylacium aduncum) yield different amplification (960 and 1,010 bp fragments) and restriction patterns, which were in accord with previously described patterns of the same parasites from others geographical regions. CONCLUSIONS: The high sensitivity of the test and the absence of intraspecies variations confirms the utility of this assay in the identification of human parasites involved in human anisakiasis including larvae from resected biopsies.

Animals↗
PubMed2004

Differential diagnosis of Taenia saginata and Taenia saginata asiatica taeniasis through PCR.

New multiplex-PCR and PCR-linked restriction fragment length polymorphism protocols, derived from Taenia saginata HDP2 DNA sequence, have been designed that allow the simultaneous and specific identification of T. saginata and Taenia saginata asiatica. Proglottids expelled from 20 different Spanish taeniasis patients, previously diagnosed as T. saginata by both morphological identification and multiplex HDP2-PCR, were also examined by the newly developed PCR protocols, and the original diagnosis of T. saginata infection was confirmed. All of the 20 T. saginata samples were negative in the T. saginata asiatica-specific PCR. Three authentic T. saginata asiatica samples were unambiguously identified as such in the T. saginata asiatica PCR. These new protocols have immediate potential for the specific, sensitive, and rapid identification of T. saginata asiatica and may assist in taxonomic studies.

Animals↗
PubMed2004

Trichinella spiralis secretes a homologue of prosaposin.

Infective larvae and adult stage Trichinella spiralis secrete a protein homologous to prosaposin, the precursor of sphingolipid activator proteins (saposins) A-D originally defined in vertebrates. The protein contains four saposin domains, with the six cysteine residues which form the three intramolecular disulphide bonds in close register in each case. It differs substantially from vertebrate prosaposins in the N-terminal prodomain, the region separating saposins A and B, and completely lacks the C-terminal domain which has been demonstrated to be essential for lysosomal targetting in these organisms. The protein is secreted in unprocessed form with an estimated mass of 56 kDa, and contains a single N-linked glycan which is bound by the monoclonal antibody NIM-M1, characteristic of the TSL-1 antigens which are capped by tyvelose (3,6-dideoxy-D-arabinohexose). Immuno-electron microscopy localised the protein to membrane-bound vesicles and more complex multi-lamellar organelles in diverse tissues including the hypodermis, intestine and stichosomes, although it was absent from the dense-core secretory granules typical of the latter. Possible functions of a secreted prosaposin are discussed.

Amino Acid Sequence↗
PubMed2003

Cloning and characterization of Taenia saginata paramyosin cDNA.

A lambdaZAP-express cDNA library of Taenia saginata metacestodes was constructed. Antibody screening yielded a clone with an insert of 3,408 bp, an open reading frame of 2,589 bp, a deduced sequence of 863 amino acid and a molecular mass of 98.89 kDa. Alignments of the predicted amino acid sequence showed identity with paramyosins from several species: 98.8% with Taenia solium, 96.3% with Echinococcus.granulosus and about 70% with Schistosoma spp. The insert was expressed and purified. A collagen binding assay was performed which showed that T. saginata GST-paramyosin retained this property in a dose-dependent manner. Problems were encountered due to high backgrounds in serological assays in the homologous T. saginata system. However, the recombinant paramyosin was recognized by antibodies present in 31.6% of sera from T. solium seropositive cysticercosis patients and 100% of the sera from acute cysticercosis patients. The immunodominant epitope was the carboxyl-terminal fragment of the molecule.

Amino Acid Sequence↗
PubMed2003

[Antiparasite therapy].

The lack of any parasite vaccine makes prevention against parasitic diseases to be based, as in the past, in ecological measures such as the environmental health and vector control to interrupt the biological cycle; on the other hand, it is also based in anti-parasite drugs. Once the disease has been acquired it is just possible to take medication. Studies on the way of action allow to understand more about the physiology of the parasite and, on the other hand, to understand better the physiology of the parasite allows to design new more effective drugs. However, the vast majority of these new drugs have been obtained thanks to intelligent and selective screening of generic molecules more than from the result of the knowledge of the biochemistry of the parasite. Despite all this, it is well known the mechanisms of action of many antiparasite drugs which have led us, when possible, to the discussion about possible targets to give an idea of how the rational approximation to design new medicaments is done.

Antiparasitic Agents↗
PubMed2002

PCR tools for the differential diagnosis of Taenia saginata and Taenia solium taeniasis/cysticercosis from different geographical locations.

The potential value of PCRs in the species-specific diagnosis of have been investigated, using samples of T. saginata and T. solium from different geographical areas. The PCRs examining inter-species differences were based on the sequence of the HDP2 DNA fragment, specific for T. saginata/T. solium, and the sequence of the rDNA internal transcribed spacer 1 and spacer 2 (ITS-1 and ITS-2). This PCR analysis of DNA isolates confirmed morphologic diagnosis and allowed the speciation of samples too small or fragmented for morphologic identification, with clear and consistent inter-species differences between T. saginata (twenty-two) and T. solium (three) geographical isolates. Possible intra-species genomic variability, within these species, was similarly studied through analysis of PCR amplification products (PCR-RFLP) and only encountered one exceptional T. saginata isolate from Kenya, which yielded a unique PCR-RFLP pattern, different from T. saginata DNA of Mexican (one sample) and Spanish (seven samples) origin.

Animals↗
PubMedDate not supplied

Monoclonal antibodies raised in Btk(xid) mice reveal new antigenic relationships and molecular interactions among gp53 and other Trichinella glycoproteins.

Tyvelose-bearing glycoproteins or Trichinella spiralis Group 1 antigens (TSL-1 antigens) are thought to be key molecules in the immunobiology of Trichinella. In the present study, we investigated the binding characteristics of several mAbs produced in Btk(xid) immunodeficient mice that recognise gp53 and some other minor glycoproteins of this parasite. The data obtained reveal the existence of an O-glycan/peptide epitope (recognised by mAb US8) common to all TSL-1 glycoproteins, as well as a specific interaction between the TSL-1 antigen gp53 and other unknown Trichinella glycoproteins in the 35-40 kDa range (these latter react with mAbs US8 and US9, but not with mAb US5). Some of the epitopes recognised by our mAbs are differentially expressed in Trichinella species: the epitope recognised by mAb US5 on gp53 (another O-glycan/peptide epitope) is present only in T. spiralis, whereas those recognised by mAbs US8 and US9 (peptide epitopes) are present in encapsulated Trichinella species. The data obtained also reveal that gp53 is synthesised and glycosylated in beta-stichocytes only. The possible relevance of these findings is discussed.

Agammaglobulinaemia Tyrosine Kinase↗
PubMedDate not supplied

Cutaneous and medullar gnathostomiasis in travelers to Mexico and Thailand.

Gnathostomiasis is a rare nematode disease acquired by travelers to endemic areas. The most common clinical presentations are cutaneous forms; however, neurologic involvement can also occur. We present two cases of gnathostomiasis, one of them with severe neurologic complications, in Spanish travelers to Thailand and Mexico, who consumed local food and became infected.

Adult↗