PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Anisakis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Genetic divergence and reproductive isolation between Anisakis brevispiculata and Anisakis physeteris (Nematoda: Anisakidae)s.

In order to assess the taxonomic status of Anisakis brevispiculata Dollfus, 1966 population samples of this taxon from central and south-eastern Atlantic ocean were compared at 22 enzymatic loci with samples belonging to Anisakis physeteris Baylis, 1923 from the Mediterranean sea and central-eastern Atlantic ocean. Very low interpopulational genetic divergence was observed both within A. brevispiculata (average D(Nei) = 0.008) and within A. physeteris (D(Nei) = 0.009) despite the geographic distance among the samples, indicating high levels of gene flow in both taxa. On the other hand, the average genetic distance between A. brevispiculata and A. physeteris was found to be D(Nei) = 0.80, a value generally observed between well differentiated congeneric species. The reproductive isolation between A. brevispiculata and A. physeteris is indicated by the following observations: (1) no F(1) hybrids or recombinant genotypes were until now observed; and (2) the two Anisakis species do not seem to share their definitive hosts. The main definitive host of A. brevispiculata is the pygmy sperm whale (Kogia breviceps), while for A. physeteris it is the sperm whale (Physeter catodon). Only adult males differ slightly in spicule length, while females and larval stages are not differentiated morphologically. Both A. brevispiculata and A.physeteris show a type II larva. The correct recognition of A. brevispiculata from A. physeteris and from other Anisakis species studied, in either sexes and at any life stage, is made easy by allozyme markers (e.g. Icdh, Gapdh, Sod-1, Np, Aat-2, Adk-2, fEst-2, PepB, PepC-2, Mpi). Diagnostic keys, which can be used for routine identification in the field of these Anisakis worms, based on genetic markers, are given.

Animals↗

Genetic markers in the study of Anisakis typica (Diesing, 1860): larval identification and genetic relationships with other species of Anisakis Dujardin, 1845 (Nematoda: Anisakidae).

Genetic variation at 21 gene-enzyme systems was studied in a sample of an adult population of Anisakis typica (Diesing, 1860) recovered in the dolphin Sotalia fluviatilis from the Atlantic coast of Brazil. The characteristic alleles, detected in this population, made it possible to identify as A. typica, Anisakis larvae with a Type I morphology (sensu Berland, 1961) from various fishes: Thunnus thynnus and Auxis thazard from Brazil waters, Trachurus picturatus and Scomber japonicus from Madeiran waters, Scomberomorus commerson, Euthynnus affinis, Sarda orientalis and Coryphaena hippurus from the Somali coast of the Indian Ocean, and Merluccius merluccius from the Eastern Mediterranean. Characteristic allozymes are given for the identification, at any life-stage and in both sexes, of A. typica and the other Anisakis species so far studied genetically. The distribution of A. typica in warmer temperate and tropical waters is confirmed; the definitive hosts so far identified for this species belong to delphinids, phocoenids and pontoporids. The present findings represent the first established records of intermediate/paratenic hosts of A. typica and extend its range to Somali waters of the Indian Ocean and to the Eastern Mediterranean Sea. A remarkable genetic homogeneity was observed in larval and adult samples of A. typica despite their different geographical origin; interpopulation genetic distances were low, ranging from D(Nei)=0.004 (Eastern Mediterranean versus Somali) to D(Nei)=0.010 (Brazilian versus Somali). Accordingly, indirect estimates of gene flow gave a rather high average value of Nm = 6.00. Genetic divergence of A. typica was, on average, D(Nei)=1.12 from the members of the A. simplex complex (A. simplex s.s, A. pegreffii, A. simplex C) and D(Nei)=1.41 from A. ziphidarum, which all share Type I larvae; higher values were found from both A. physeteris (D(Nei)=2.77)

Alleles↗

Anisakis and eosinophil. I. Detection of a soluble factor selectively chemotactic for eosinophils in the extract from Anisakis larvae.

Studies were undertaken in order to determine if Anisakis larva itself has the ability to attract eosinophils. Extracts from Anisakis larvae were examined for both neutrophil and eosinophil chemotactic activities with both in vivo and in vitro assay systems. When the soluble extract was injected intradermally into normal guinea pigs, a profound accumulation of eosinophils was observed at the injection site. The cells started to accumulate at the site within 1 hr and the number of eosinophils at the site reached its peak at 8 hr after the injection of the extract. Such eosinophilic accumulation was enhanced in a dose-response fashion over the range of 0.5 to 50 micrograms protein. The strong chemotatic activity of the Anisakis extract for eosinophils was confirmed when in vitro chemotaxis assays were performed with Boyden chemotatic chambers. Interestingly, no chemotactic activity for neutrophils was found at those concentrations of the extract with which the eosinophil effect was observed. These results indicate that the factor described here, in addition to the various known immunologic factors, may play an important role in the development of eosinophilia in anisakiasis.

Animals↗

Genetic structure of Anisakis physeteris, and its differentiation from the Anisakis simplex complex (Ascaridida: Anisakidae).

The genetic structure of Anisakis physeteris from the Mediterranean Sea has been analysed electrophoretically at 22 enzyme loci. The samples studied, although differing in the life-stage (larvae and adults), and in the host (the fishes Micromesistius poutassou and Trachurus trachurus, and the sperm whale Physeter macrocephalus) were genetically homogeneous. Of these loci 11 (Ldh, Sod, Np, Adk-2, Pgm-1, Est-1, Est-2, Acph-1, Acph-2, Lap-2 and Ca) were found to be monomorphic, while the other 11 (Sdh, Mdh, Idh, 6-Pgdh, G3pdh, Got, Adk-1, Pgm-2, Lap-1, Mpi and Gpi) showed from 2 to 7 alleles. The following values of genetic variability were estimated: He = 0.11, P = 0.50, A = 1.95. Distinct alleles were found between A. physeteris and the A. simplex complex at 19 out of the 22 loci studied, and only few rare alleles were shared at the remaining 3 loci. The genetic divergence between A. physeteris and A. simplex A and B is therefore very high, the values of Nei's index D being 7.384 and 6.443 respectively (I = 0.001 and 0.002). The assignation of A. physeteris and the A. simplex complex to two distinct subgenera, Skrjabinisakis and Anisakis, as proposed by Mosgovoy on a morphological basis, appears to be fully justified according to our genetic data.

Alleles↗

The identity of Anisakis type II larvae with Anisakis physeteris confirmed by restriction fragment length polymorphism analysis of genomic DNA.

The identity of Anisakis type II larvae with adult A. physeteris was confirmed by comparison of restriction fragment length polymorphisms (RFLPs) of 25S ribosomal DNA (rDNA). Patterns of RFLPs in larvae were almost identical with those in adult worms. Directly labelled 25S rDNA might serve as an appropriate probe with highly specific activity for examining RFLPs of larvae and adult worms.

Animals↗

Anisakis, anisakiasis and IgE-mediated immunity to Anisakis simplex.

Anisakis simplex is a common parasite in fish and cephalopods and is not only capable of causing anisakiasis in humans through visceral invasion of the third-stage larvae but can also cause anaphylactic reactions, as has recently been demonstrated. We present the clinical case of a 56-year-old man who initially presented anaphylactic reactions related to eating fish. Shortly afterwards, he began to experience self-limiting recurrences of very intense epigastric pain, nausea and vomiting. Skin tests for immediate hypersensitivity (prick tests) with a commercial extract as well as the determination of specific IgE in the patient's serum were clearly positive for A. simplex. The hemogram did not show eosinophilia. Copro-cultures and parasites in the patient's feces were repeatedly negative. Gastroscopy was normal. The intestinal tract showed contrast flocculation and dilation of ansas in the distal duodenum and proximal jejunum. Biopsy samples of gastric and distal duodenum mucous showed an active process of chronic inflammation with a predominance of eosinophils in the lamina propria. After subjecting the patient to a fish and cephalopod-free diet and treating him with thiabendazole 350 mg every 12 hours for 6 days, he showed no sign of symptoms while awaiting new tests. Even though the diagnosis of IgE-mediated allergy caused by A. simplex offers no room for doubt, we are unable to present a firm diagnosis of anisakiasis as no larva has been seen. Nevertheless, the clinical pattern, the image of the intestinal tract, the eosinophilic infiltrate in the biopsies and the good response to thiabendazole all lead to the suspected existence of anisakiasis in this patient coexisting with IgE-mediated allergy to this parasite.

Anaphylaxis↗

Usefulness of currently available methods for the diagnosis of Anisakis simplex allergy.

BACKGROUND: Serodiagnosis of anisakiosis and Anisakis allergy is difficult since many Anisakis antigens show cross-reactivity complications. In the present study, we assess the usefulness of the major immunologic methods currently available for the diagnosis of Anisakis allergy. METHODS: Four tests (skin prick test, CAP-FEIA system, Western blotting, and an antigen-capture ELISA using O-deglycosylated antigen bound by the monoclonal antibody UA3) were applied to Anisakis-free subjects and subjects with confirmed Anisakis allergy. RESULTS: The skin prick test, CAP-FEIA, and the antigen-capture ELISA identified Anisakis allergy sera with 100% sensitivity, while Western blotting showed 96%/ sensitivity. The antigen-capture ELISA also showed 100% specificity, but CAP-FEIA showed a specificity of only 50%. In Western blotting, none of the bands detected were specific for either Anisakis-free or Anisakis allergy subjects. The skin prick test was not applied to the Anisakis-free subjects, so its specificity could not be determined. CONCLUSIONS: On the basis of these results, we suggest that the most appropriate procedure for diagnosis of Anisakis allergy suspected on clinical grounds is the antigen-capture ELISA using UA3, or, alternatively, a preliminary skin prick test with a positive result subsequently confirmed by UA3-ELISA.

Adolescent↗

O-glycans as a source of cross-reactivity in determinations of human serum antibodies to Anisakis simplex antigens.

BACKGROUND: Anisakis simplex is a seafood-borne parasite that may both infect humans and cause allergy. Serodiagnosis of anisakiasis and allergy caused by this nematode is difficult since most Anisakis antigens show cross-reactivity problems. OBJECTIVE: To analyse the possible role of sugar epitopes contained in Anisakis simplex antigens as causes of false-positive results in serodiagnostic assays. METHODS: The antigens UA2R and UA3R recognized by two anti-Anisakis monoclonal antibodies were used in this study. Capture ELISA techniques were used to compare the reactivities with native or O-deglycosylated antigens of sera from Anisakis-free children (most of them infected by several other parasites) and from Anisakis allergy patients. O-deglycosylation was done by mild alkali treatment with NaOH. SDS-PAGE and immunoblotting were used to characterize the effects of NaOH or N-glycanase F treatment on UA3R. RESULTS: Native UA2R was recognized by IgG1 and IgM antibodies in the sera of both Anisakis-free subjects and allergy patients. Native UA3R was recognized by most sera from allergy patients (92% considering immunoglobulin (Ig) G1, 100% considering IgE), but also by a significant proportion of sera from Anisakis-free subjects (36% considering IgG1, 14% considering IgE). O-deglycosylation of UA3R greatly improved specificity: none of the sera from Anisakis-free patients showed either IgG1 or IgE reactivity with O-deglycosylated UA3R, while the proportion of sera from allergy patients showing IgE reactivity with this antigen was practically unaffected. O-deglycosylation of UA2R did not improve the specificity of assays using this antigen. Our results also show that the protein core of glycoproteins may be altered by even very mild alkali treatment, depending on the nature of the protein. CONCLUSION: Native glycoproteins of A. simplex should not be used for diagnostic purposes. O-deglycosylated UA3R seems to be an excellent candidate for use as target antigen in the serodiagnosis of anisakiasis and A. simplex allergy.

Animals↗

Specific IgE determination to Ani s 1, a major allergen from Anisakis simplex, is a useful tool for diagnosis.

BACKGROUND: The most serious limitation of the serodiagnosis of parasitoses is the occurrence of cross-reactions. OBJECTIVE: The possible use of Anisakis simplex major allergen Ani s 1 for diagnosis. PATIENTS AND METHODS: Forty-nine non-fish-allergic patients with Anisakis simplex hypersensitivity, 21 patients without allergic episodes suffering intestinal anisakiasis with obstruction of the intestinal lumen, and 10 unrelated sera as a control were included in this study to determine specific immunoglobulin (Ig)E and IgG to Anisakis simplex major allergen Ani s 1 by immunoblotting. RESULTS: Eighty-six percent of patients with Anisakis simplex hypersensitivity showed specific IgE directed to Ani s 1. Identical result was obtained for IgG detection in this group. Among patients with intestinal anisakiasis, 86% showed specific IgE, but only 29% had specific IgG (P < 0.001, two-tailed Fisher exact test). One of the 10 control subjects was positive both for IgE and IgG (P < 0.001). CONCLUSIONS: Determination of specific IgE directed to Anisakis simplex major allergen Ani s 1 is a useful tool for the diagnosis of hypersensitivity and intestinal anisakiasis. Further, measurement of specific IgG directed to Anisakis simplex major allergen Ani s 1 is only valid for Anisakis simplex allergy.

Allergens↗

Incidence of sensitivity to Anisakis simplex in a risk population of fishermen/fishmongers.

BACKGROUND: Anisakis simplex, a fish and cephalopodes parasite, can cause either gastrointestinal symptoms or allergic reactions in humans on eating/handling contaminated fish. OBJECTIVE: The aim of our study was to determine the capacity of Anisakis simplex to induce specific IgE production and allergic reactions following eating and handling fish in a population at risk. METHODS: We determined the levels of total IgE, specific IgE, and eosinophil count in 28 fishermen/fishmongers (group A) and 15 healthy donors (group B). A skin prick test (SPT) with extracts from Anisakis and the most common species of fish in our country, were also carried out. RESULTS: Specific IgE to Anisakis were found in 14 subjects of group A (13 of them had a positive SPT to the same extract) and none of group B (only one subject had a positive SPT). The SPT with fish extracts was positive in 4 patients of group A but in none of group B. Subjects in group A with specific IgE to Anisakis showed higher total IgE levels and eosinophil counts compared with either other individuals of the same group or to those of group B. CONCLUSIONS: These results indicate that fishermen/fishmongers are a population at risk for Anisakis simplex sensitization and suggest that this kind of sensitization should also be investigated not only in subjects like fishermen/fishmongers who live in countries where fish is likely to be contaminated with Anisakis simplex parasites, but also in those who handle fish for other reasons.

Adolescent↗

Genetic markers in ribosomal DNA for the identification of members of the genus Anisakis (Nematoda: ascaridoidea) defined by polymerase-chain-reaction-based restriction fragment length polymorphism.

Polymerase-chain-reaction-based restriction fragment length polymorphism analysis was performed to establish genetic markers in rDNA, for the identification of the three sibling species of the Anisakis simplex complex and morphologically differentiated Anisakis species, i.e. Anisakis physeteris, Anisakis schupakovi, Anisakis typica and Anisakis ziphidarum. Different restriction patterns were found between A. simplex sensu stricto and Anisakis pegreffii with two of the restriction endonucleases used (HinfI and TaqI), between A. simplex sensu stricto and A. simplex C with one endonuclease (HhaI), and between A. simplex C and Aniskis pegreffii with three endonucleases (HhaI, HinfI and TaqI), while no variation in patterns was detected among individuals within each species. The species A. physeteris, A. schupakovi, A. typica and A. ziphidarum were found to be different from each other and different from the three sibling species of the A. simplex complex by distinct fragments using 10-12 of the endonucleases tested. The polymorphisms obtained by restriction fragment length polymorphisms have provided a new set of genetic markers for the accurate identification of sibling species and morphospecies.

Animals↗

[Analysis of antigens defined by anti-Anisakis larvae antibodies of IgE and IgG type in the sera of patients with acute gastrointestinal anisakiasis].

Using SDS-PAGE and Immunoblotting assay, we analysed antigens defined by anti-Anisakis Larvae antibodies of IgE and IgG type in the sera of patients with acute gastrointestinal anisakiasis. 1) Humoral IgE response to 76, 64 and 60 kDa molecular weight proteins of Anisakis Larvae and IgG response to 91, 76, 64 and 60 kDa molecular weight proteins were demonstrated in the sera of patients with acute gastric anisakiasis. Those humoral antibody responses were also demonstrated in the sera of two patients with intestinal anisakiasis. 2) Those antibodies to 76, 64 and 60 kDa proteins may be Anisakis-specific antibodies, because anti-Anisakis Larvae antibodies of IgE and IgG type did not react with the similar MW proteins of Ascaris suum homogenates. 3) Also anti-Anisakis Larvae antibodies reacted with Anisakis Excretory and Secretory (E.S.) protein which included specific 76 and 60 kDa proteins, but they did not react with purified Anisakis hemoglobin.

Acute Disease↗

Human immunoglobulin isotype profiles produced in response to antigens recognized by monoclonal antibodies specific to Anisakis simplex.

BACKGROUND: Anisakis simplex is a medically important pathogen which not only causes anisakiasis but may provoke allergy reactions, ranging from mild urticaria to anaphylactic shock. OBJECTIVE: To investigate anti-Anisakis isotype profiles in anisakiasis and Anisakis allergy patients. METHODS: Capture ELISA techniques were used to investigate the isotype profiles of antibodies specific for two defined Anisakis simplex antigens, in serum from Japanese patients with confirmed anisakiasis and from Spanish patients with allergy to Anisakis. The antigens were 'UA2R antigens' (two proteins with MW of 48 and 67 kDa, recognized by our monoclonal antibody UA2) and 'UA3R antigens' (two proteins with MW of 139 and 154 kDa, recognized by our monoclonal antibody UA3). RESULTS: Considering IgG, the two most frequent isotypes in the response to the UA2R antigens were IgG1 and IgG2, with IgG4 detected in only one case; in response to the UA3R antigens, by contrast, the two most frequent isotypes were IgG1 and IgG4 (though IgG2 remained reasonably frequent). As regards potential utility for serodiagnosis, 95% of the Japanese anisakiasis patients and 84% of the allergy patients showed detectable IgG1 antibodies to the UA3R antigens. Furthermore, all allergy patients showed IgE antibodies to these antigens. CONCLUSION: Anisakis simplex contains antigens that induce responses which are differentially regulated. Because of their immunogenicity, immunodominance and allergenic nature, we consider that the 139/154-kDa antigens recognized by our MoAb UA3 are good candidates for use in tests for the diagnosis of anisakiasis and of the allergy caused by this parasite.

Anaphylaxis↗

Allergic reactions to anisakis simplex parasitizing seafood.

BACKGROUND: The ingestion of Anisakidae ssp larvae parasitized fish can cause anisakiasis. Allergic reactions after ingestion of safely cooked but parasitized fish have been reported. METHODS: Twenty-three patients who suffered allergic reactions after seafood ingestion, with negative skin tests were studied. Anisakis simplex sensitization was assessed by skin prick test and/or specific serum Immunoglobulin E (IgE). Total serum IgE and specific IgE against the implicated seafood and Ascaris lumbricoides were also determined. RESULTS: Manifestations of Anisakis simplex allergy were urticaria/angioedema (18/23) patients and anaphylaxis (5/23). Gastric symptoms were also observed (3/23). Sea fish and shellfish were implicated. Raw and cooked seafood ingestion caused reactions. Total serum IgE ranged from 13 to 7200 KU/L. Specific IgE to Anisakis simplex was positive (> 0.35 KU/L) in all patients, and skin tests were positive in 20. Serum-specific IgE and skin tests to the involved seafoods were negative in every patient. Serum-specific IgE to Ascaris lumbricoides was negative in 13 patients. No association between total IgE and the eosinophil count (r < 0.1) was observed, but there was some association between total IgE and specific IgE to Anisakis simplex (r = 0.58). CONCLUSION: Anisakis simplex sensitization is the cause of allergic reactions after seafood ingestion. It is important to pay attention to this new "food allergy" to diagnose correctly the etiology of adverse food reactions.

Adolescent↗