[show abstract][hide abstract] ABSTRACT: Objectives To improve the diagnosis of human fascioliasis caused by Fasciola hepatica and Fasciola gigantica, we evaluated the diagnostic accuracy of an enzyme-linked immunosorbent assay (ELISA), with Fasciola antigen from the adult liver fluke, for the detection of IgG against fascioliasis in human sera. Methods The sera of 54 fascioliasis cases, originating from three endemic areas, were used in this evaluation: (i) a hyperendemic F. hepatica area where humans usually shed a great number of parasite eggs in faeces (11 sera); (ii) an epidemic F. hepatica area where humans usually shed small amounts of parasite eggs (24 sera) and (iii) an overlap area of both Fasciola species and where human shedding of parasite eggs in faeces is usually scarce or non-existent (19 sera). One hundred and sixty-eight patients with other parasitic infections and 89 healthy controls were also analysed. Results The respective sensitivity and specificity of this assay were 95.3% (95% confidence intervals, 82.9-99.2%) and 95.7% (95% confidence intervals, 92.3-97.5%). No correlation between egg output and the OD450 values of the F. hepatica IgG ELISA test was observed. Conclusions This test could be used both as an individual serodiagnostic test for human fascioliasis when backed up by a compatible clinical history together with a second diagnostic technique for other cross-reactive helminth infections, and in large-scale epidemiological studies of human fascioliasis worldwide.
Tropical Medicine & International Health 03/2012; 17(5):630-6. · 2.94 Impact Factor
[show abstract][hide abstract] ABSTRACT: The etiological agents of human trichinellosis are distributed worldwide in domestic and wild animals. In Spain, two morphologically indistinguishable Trichinella species have been described--Trichinella spiralis and Trichinella britovi--that are perpetuated in both domestic and sylvatic cycles. The present work reports a double natural infection involving these species in a wild boar killed by hunters in the Province of Cáceres, Spain. After artificial digestion of the boar's muscles, nine larvae/g were collected. These were characterized by multiplex-PCR and Western-blotting using the Trichinella-specific monoclonal antibodies US5 and US9, and both T. spiralis and T. britovi were detected. The mechanism by which this wild boar came to acquire a mixed infection remains unclear.
[show abstract][hide abstract] ABSTRACT: 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.
Medical Microbiology and Immunology 04/2006; 195(1):1-10. · 3.55 Impact Factor
[show abstract][hide abstract] ABSTRACT: To identify Trichinella antigens suitable for high-specificity and high-sensitivity serodiagnosis of human trichinellosis, we evaluated assays using four antigens: (i) crude first-stage larval extract (CLE), (ii) O-deglycosylated CLE, (iii) tyvelose-bearing antigens (Trichinella spiralis larva group 1 [TSL-1] antigens) purified by US4 affinity chromatography and coupled directly to enzyme-linked immunosorbent assay (ELISA) plates (pTSL-1 antigens), and (iv) TSL-1 antigens immobilized on ELISA plates with the monoclonal antibody (MAb) US4 (cTSL-1 antigens). Assays using these antigens were compared by analysis of sera from healthy individuals (n = 224) (group 1), individuals with noninfectious intestinal pathologies (n = 114) (group 2), individuals with other parasitic infections (n = 107) (group 3), and individuals with confirmed trichinellosis (n = 42) (group 4). Our results indicate that capture ELISA using cTSL-1 antigens is the most effective method for serodiagnosis of human trichinellosis; this was the only method showing 100% specificity and 100% sensitivity at the patent stage of the infection, and it was also the most sensitive for sera obtained prior to patency in indirect immunofluorescence (IIF). Indirect ELISA with pTSL-1 antigens was also 100% specific but was slightly less sensitive, particularly with sera obtained before IIF patency. Inhibition ELISA with MAb US4 indicated (i) that in Trichinella-infected patients the immune response to TSL-1 antigens is directed mostly against tyvelose-containing epitopes (mean of 84.2% of total anti-TSL-1 immunoglobulin G1 [IgG1] antibody response [range, 51.3 to 97.6%]) and (ii) that in most individuals a large proportion of anti-CLE IgG1 antibodies (mean, 49.5%; range, 7.3 to 92.6%) are directed against tyvelose epitopes.
Journal of Clinical Microbiology 10/2004; 42(9):4060-6. · 4.07 Impact Factor
[show abstract][hide abstract] ABSTRACT: We intended to develop a molecular test allowing a species-specific identification of the anisakid human parasite independently of its evolutive stage.
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.
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.
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.
[show abstract][hide abstract] ABSTRACT: 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.
[show abstract][hide abstract] ABSTRACT: Background and objective
We intended to develop a molecular test allowing a species-specificidentification 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 approximately70 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.
Different anisakids (Anisakis simplex/Hysterothylacium aduncum) yield different amplification(960 and 1,010 bp fragments) and restriction patterns, which were in accord withpreviously described patterns of the same parasites from others geographical regions.
The high sensitivity of the test and the absence of intraspecies variations confirmsthe utility of this assay in the identification of human parasites involved in humananisakiasis including larvae from resected biopsies.
Medicina Clinica - MED CLIN. 01/2004; 122(18):686-689.
[show abstract][hide abstract] ABSTRACT: Els paràsits són els més oblidats dels microorganismes patògens. El fet que la seva major prevalença es doni als països de l'àrea tropical, països pobres en la seva major part, potser influeix en aquest fet. Actualment es disposen de diferents productes amb capacitat de combatre infeccions d'aquests microorganismes.