Morphological and Molecular Characteristics of Anisakis typica Larvae in Two Species of Threadfin Bream, Nemipterus hexodon and N. japonicus, from the Gulf of Thailand.

The third stage larvae (L3) of Anisakis typica were detected in 2 species of threadfin bream, Nemipterus hexodon and N. japonicus, from the Gulf of Thailand, and were morphologically and molecularly characterized. Total 100 threadfin breams, 50 Nemipterus hexodon and 50 N. japonicus, were examined with naked eyes after the opening of abdominal cavity with scissors. Almost all infected larvae remained alive and active even the fish were transported for 1-2 days. Anisakid larvae were exclusively distributed in the body cavity and rarely in the liver. The prevalence of A. typica L3 were 68.0% and 60.0% in N. hexodon and N. japonicus and their infection intensities were 3.5 and 4.2 per fish infected each. Morphological and morphometric analysis were performed by viewing specimens under both a light microscope and a scanning electron microscope. Interestingly, the protruded mucron of Anisakis typica under SEM showed a distinct cylindrical shape that differed from the cone shape of A. simplex. The protruded mucron could be used to identify A. typica L3 larvae in the future. A comparison of the ITS1-5.8S-ITS2 rDNA nucleotide sequences of these species revealed high blast scores with A. typica. Conclusively, it was confirmed that A. typica L3 are prevalent in threadfin breams from the Gulf of Thailand, and their morphological and molecular characters are something different from those of other anisakid larvae, including A. simplex and A. pegreffii.

A scanning electron microscopy study of Anisakis physeteris molecularly identified: from third stage larvae from fish to fourth stage larvae obtained in vitro.

The development of the fourth larval stage (L4) of Anisakis physeteris was studied using scanning electron microscopy (SEM), comparing it with third larval stage (L3) recently obtained from the host fish, blue whiting (Micromesistius poutassou), from the western Mediterranean Sea (east coast of Spain, zone FAO 37.1.1). After molting to L4, samples of the parasite were examined at different times in order to observe their development. Following collection of the L4, a small portion was taken from the middle of the larva for molecular identification, confirming in all cases that it was A. physeteris. The anterior and posterior sections of the larvae were prepared for morphological study by SEM. The development of a row of denticles on each of the three prominent lips, almost reaching the buccal commisures, was observed in the L4. Pores of unknown function were found in the upper external part of each lip. Clearly developed cephalic papillae, amphids, and deirids were also observed in L4, while, although present in L3, these were beneath the cuticle. Phasmids were detected in L4 but not in L3. The L4 tail finished in a conical lobe with a blunt point, absent in L3. In the oldest L4, some preanal papillae were observed beneath the cuticle in males, while, in females, the vulva could be seen by light microscopy, apparently still covered by the cuticle.

Morphological and genetic identification of Anisakis paggiae (Nematoda: Anisakidae) in dwarf sperm whale Kogia sima from Brazilian waters.

Anisakid nematodes have been identified in a wide variety of fish and marine mammal species. In Brazil, Anisakis physeteris, A. insignis, A. typica, A. nascetti, and those of the A. simplex complex have been reported infecting fishes and cetaceans. In this study, specimens collected from a dwarf sperm whale Kogia sima (Owen, 1866) stranded on the northeastern coast of Brazil were identified through morphological and genetic analyses as A. paggiae. Anisakids were examined through differential interference contrast light and scanning electron microscopy (SEM). Morphological and morphometric analysis revealed that these specimens belonged to Anisakis sp. clade II and more specifically to A. paggiae, exhibiting a violin-shaped ventriculus and 3 denticulate caudal plates, which are taxonomic characters considered unique to this species. Genetic analysis based on the mtDNA cox2 gene confirmed our identification of A. paggiae. Phylogenetic trees using both maximum likelihood and neighbor-joining methods revealed a strongly supported monophyletic clade (bootstrap support = 100%) with all available A. paggiae sequences. Integrative taxonomic analysis allowed the identification of A. paggiae for the first time in Brazilian waters, providing new data about their geographical distribution. Moreover, here we present the first SEM images of this species.

Activity of Thymus vulgaris essential oil against Anisakis larvae.

Anisakiasis is an important food-borne disease especially in countries with high fish consumption. The increase of cases of human disease and the virtual absence of effective treatments have prompted the research on new active compounds against Anisakis larvae. As well known, the disease is related to the consumption of raw or almost raw seafood products, but also marinated and/or salted fishery products, if the processing is insufficient to destroy nematode larvae can represent a risks for the consumers. In the light of the biocidal efficacy against different pathogens demonstrated for various essential oils, the aim of this work is to evaluate the effect of Thymus vulgaris essential oil (TEO) against anisakidae larvae. The TEO at 10% and 5% concentration in oil sunflower seeds, caused in vitro the death of all larvae within 14 h, with cuticle and intestinal wall damages. The results obtained showing a significant activity against Anisakis larvae, suggest further investigation on TEO as a larvicidal agent and on its potential use in the industrial marinating process.

Genetic and morphological characterisation of a new species of the genus Hysterothylacium (Nematoda) from Paralichthys isosceles Jordan, 1890 (Pisces: Teleostei) of the Neotropical Region, state of Rio de Janeiro, Brazil.

Taking into account the difficulties of taxonomic identification of larval anisakid nematodes based on morphological characters, genetic analyses were performed, together with those usually applied, in order to identify anisakid larvae found in the flounder Paralichthys isosceles from the littoral of the state of Rio de Janeiro, Brazil. The analysis of 1,820 larvae revealed a new species, similar to Hysterothylacium MD, Hysterothylacium 2, Hysterothylacium KB and Hysterothylacium sp regarding the absence of the larval tooth, an excretory pore situated below the nerve ring level, and slender lateral alae. Moreover, the new species differs from Hysterothylacium fortalezae and Hysterothylacium reliquens with regard to the number and size of spines present on the tail end and from Hysterothylacium patagonicus by the absence of interlabia. The maximum parsimony and neighbour joining tree topologies based on the 18S ribosomal DNA gene, complete internal transcribed spacer region and cytochrome oxidase 2 (COII) gene demonstrated that the Brazilian larvae belong to Raphidascarididae and represent a unique genetic entity, confirmed as a new Hysterothylacium species. Furthermore, the new species presents COII genetic signatures and shares polymorphisms with Raphidascarididae members. This is the first description of a new anisakid species from Brazil through the integration of morphological and molecular taxonomy data.

First record of anisakid juveniles (Nematoda) in the European seabass Dicentrarchus labrax (family: Moronidae), and their role as bio-indicators of heavy metal pollution.

This study assessed the anisakid nematode distribution pattern in the fish collected from coasts of Mediterranean Sea, Egypt, during the period September 2010-April 2011. Two hundred thirty out of 300 (76.7%) Dicentrarchus labrax (European seabass) marine fishes belonging to family Moronidae were dissected and found to be infected with larva three nematodes. The larvae had been studied by light and scanning electron microscopy. The present work represents the first record of the presence of the parasite in this fish in the Mediterranean Sea. The concentrations of some heavy metals (Pb, Zn, Fe, Cd, Cu, Mn, Ni) in parasites as well as in tissues of fish were measured. The presented results showed that the nematode parasites are able to accumulate heavy metals in their tissues and in some cases that they are able to accumulate large amounts of heavy metals in a higher amount than host tissues. This demonstrated their sustainability as bioindicators of environmental pollution by removing heavy metals and help in the survival of fish.

Stereo and scanning electron microscopic studies of the third stage larvae of Anisakis simplex.

This study was to demonstrate the surface anatomy of the third stage larvae of Anisakis simplex in marine fish using stereo and scanning electron microscopes (SEM). The round worm is slender, elongated and of cylindrically shaped. The head of this worm is a globular structure. The mouth is triangularly shaped and surrounded by three lips. A boring tooth projects dorsally at the anterior end. There are four pairs of tactoreceptors, the labial papillae, enclosing the lips. The tail end is blunt and acquires a distinct slender process, the mucron. Stereomicroscopy revealed the esophagus is elongated, bulbous and club shaped, subdivided into an anterior muscular part and a posterior glandular part or ventriculus. The intestine is a long straight tube where the digestion and absorption occur. Waste pass through the intestine and is stored in the rectum until excreted via the anus. A SEM is a powerful tool in distinguishing worm species, as was seen when examining that the mouth of Anisakis simplex, which is triangular shaped and enclosed by three lips with one boring tooth; other species are different. The mucron projection at the distal end is another distinctive structure revealed by SEM.

Raphidascaris (Sprentascaris) lanfrediae sp. nov. (Nematoda: Anisakidae) from the fish Satanoperca jurupari (Osteichthyes: Cichlidae).

Raphidascaris (Sprentascaris) lanfrediae sp. nov. is described from the intestine of the freshwater fish Satanoperca jurupari (Heckel) (Cichlidae) from the Guamá River, state of Pará, Brazil. The prevalence in fish (n = 59) was 27% with intensity of one-124 (mean 16) nematodes per fish. The new species is characterized mainly by the markedly larger size of ventricular appendix in relation to the oesophagus, presence of short male caudal alae, 14-16 subventral pairs of preanal papillae and six pairs of postanal papillae.

Antigenicity and viability of Anisakis larvae infesting hake heated at different time-temperature conditions.

Heat treatments (40 to 94 degrees Celsius, 30 s to 60 min) were applied to different batches of Anisakis simplex L3 larvae isolated from hake ovaries and viscera to study the effect of heat on the viability of the larvae measured as mobility, emission of fluorescence under UV light, and changes in color after staining with specific dyes, and on A. simplex antigenic proteins. The aim was to determine the lowest time-temperature conditions needed to kill the larvae to avoid anisakiasis in consumers, and to evaluate whether high temperature modifies the antigenicity of A. simplex extracts. Heating at 60 degrees Celsius for 10 min (recommended by some authors) was considered unsafe, as differences in viability between batches were found, with some larvae presenting spontaneous movements in one batch. At higher temperatures (> or = 70 degrees Celsius for > or = 1 min), no movement of the larvae was observed. Antigenic protein Ani s 4 and A. simplex crude antigens were detected in the larvae heated at 94 + or - 1 degrees Celsius for 3 min. This indicates that allergic symptoms could be provoked in previously sensitized consumers, even if the larvae were killed by heat treatment.

New records of anisakid nematodes from marine fishes off New Caledonia, with descriptions of five new species of Raphidascaris (Ichthyascaris) (Nematoda, Anisakidae).

Recent examinations of anisakid nematodes (Anisakidae) from marine fishes off New Caledonia, collected in the years 2003-2008, revealed the presence of the following five new species of Raphidascaris Railliet et Henry, 1915, all belonging to the subgenus Ichthyascaris Wu, 1949: Raphidascaris (Ichthyascaris) spinicauda n. sp. from the redbelly yellowtail fusilier Caesio cuning (Caesionidae, Perciformes); Raphidascaris (Ichthyascaris) fasciati n. sp. from the blacktip grouper Epinephelus fasciatus (Serranidae, Perciformes); Raphidascaris (Ichthyascaris) nudicauda n. sp. from the brushtooth lizardfish Saurida undosquamis (Synodontidae, Aulopiformes); Raphidascaris (Ichthyascaris) euani n. sp. from the Japanese large-eye bream Gymnocranius euanus (Lethrinidae, Perciformes); and Raphidascaris (Ichthyascaris) elopsis n. sp. from the Hawaiian ladyfish Elops hawaiensis (Elopidae, Elopiformes). An additional two congeneric species, R. (I.) etelidis Moravec et Justine, 2012 and R. (I.) sillagoides (Bruce, 1990) were found in the deep-water red snapper Etelis carbunculus (new host record) and the deepwater longtail red snapper Etelis coruscans (both Lutjanidae, Perciformes), and the silver sillago Sillago sihama (Sillaginidae, Perciformes) (new host and geographical records), respectively. Two unidentified congeneric species, Raphidascaris (Ichthyascaris) sp. 1 from the trumpet emperor Lethrinus miniatus (Lethrinidae, Perciformes) and Raphidascaris (Ichthyascaris) sp. 2 from the white-spotted puffer Arothron hispidus (Tetraodontidae, Tetraodontiformes) were recorded. Moreover, two species of Hysterothylacium Ward et Magath, 1917, H. alatum Moravec et Justine, 2015 and H. epinepheli (Yamaguti, 1941), were found in the leopard coralgrouper Plectropomus leopardus (type host) and the highfin grouper Epinephelus maculatus (new host) (both Serranidae, Perciformes), respectively. This is the second finding of H. epinepheli since its original description in Japan 79 years ago. Most species are described based on light and electron microscopical studies.

TITLE: Nouvelles mentions de nématodes anisakidés de poissons marins de Nouvelle-Calédonie, avec description de cinq nouvelles espèces de Raphidascaris (Ichthyascaris) (Nematoda, Anisakidae). ABSTRACT: L'examen récent de nématodes Anisakidae de poissons marins de la Nouvelle-Calédonie, collectés dans les années 2003­2008, a révélé la présence des cinq nouvelles espèces de Raphidascaris Railliet et Henry, 1915, toutes appartenant au sous-genre Ichthyascaris Wu, 1949 : Raphidascaris (Ichthyascaris) spinicauda n. sp. chez le fusilier Caesio cuning (Caesionidae, Perciformes) ; Raphidascaris (Ichthyascaris) fasciati n. sp. chez la loche Epinephelus fasciatus (Serranidae, Perciformes) ; Raphidascaris (Ichthyascaris) nudicauda n. sp. chez le poisson-lézard Saurida undosquamis (Synodontidae, Aulopiformes) ; Raphidascaris (Ichthyascaris) euani n. sp. chez le bossu Gymnocranius euanus (Lethrinidae, Perciformes) ; et Raphidascaris (Ichthyascaris) elopsis n. sp. chez Elops hawaiensis (Elopidae, Elopiformes). Deux autres espèces congénériques, R. (I.) etelidis Moravec et Justine, 2012 et R. (I.) sillagoides (Bruce, 1990) ont été trouvées respectivement chez les vivaneaux de profondeur Etelis carbunculus (nouvel hôte) et Etelis coruscans (Lutjanidae, Perciformes) et chez Sillago sihama (Sillaginidae, Perciformes) (nouvel hôte et nouvelle mention géographique). Deux espèces congénériques non identifiées, Raphidascaris (Ichthyascaris) sp. 1 chez le bossu Lethrinus miniatus (Lethrinidae, Perciformes) et Raphidascaris (Ichthyascaris) sp. 2 chez Arothron hispidus (Tetraodontidae, Tetraodontiformes) sont signalées. De plus, deux espèces d'Hysterothylacium Ward et Magath, 1917, H. alatum Moravec et Justine, 2015 et H. epinepheli (Yamaguti, 1941), ont été trouvées chez la saumonée Plectropomus leopardus (hôte-type) et chez la loche uitoé Epinephelus maculatus (nouvel hôte) (Serranidae, Perciformes), respectivement. Il s'agit de la deuxième mention d'H. epinepheli depuis sa description originale au Japon il y a 79 ans. La plupart des espèces ont été décrites sur la base d'études au microscope optique et électronique.

Morphological differences between larvae and in vitro-cultured adults of Anisakis simplex (sensu stricto) and Anisakis pegreffii (Nematoda: Anisakidae).

Proper identification of Anisakis species infecting host fishes is very important to both human health and fish disease diagnosis. The foremost problem in the identification of Anisakis larvae in fishes is that L3 larvae cannot be easily differentiated morphologically, especially between A. simplex (sensu stricto) (s.s.) (Rudolphi, 1809) and A. pegreffii Campana-Rouget et Biocca, 1955. Instead, molecular means such as allozyme, mitochondrial DNA (mtDNA) cox2 region and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses had been successfully used. In this study, morphological differences of L3 larvae collected from fishes and in vitro-cultured L4 larvae and adult A. simplex (s.s.) and A. pegreffii were evaluated. Anisakis larvae were collected from 7 different host fishes within Japan. Undamaged A. simplex (s.s.) and A. pegreffii collected from Oncorhynchus keta (Walbaum) and Scomber japonicus Houttuyn, respectively, were used for in vitro-culture in order to obtain L4 and adult stages. Species identification was confirmed by PCR-RFLP analysis of the ITS region (ITS1-5.8S-ITS2) of ribosomal DNA and by mtDNA cox2 gene sequencing. Results revealed that L3, L4 and adult stages of A. simplex (s.s.) and A. pegreffii are morphologically distinguishable based on ventriculus length, wherein the former has longer ventriculus (0.90-1.50 mm) than the latter (0.50-0.78 mm). For oesophagus/ventriculus ratio, these two species are distinguishable only during L4 and adult stages. Also, adult male A. simplex (s.s.) and A. pegreffii were found to be distinguishable by differences in the distribution pattern of the caudal papillae, particularly the 3rd pair of distal papillae.

Allergenic properties and cuticle microstructure of Anisakis simplex L3 after freezing and pepsin digestion.

This article examines the viability of and the alterations to the larval cuticle and the pattern of the antigens released when live or frozen Anisakis simplex larvae were treated with acid and pepsin. The results showed that freezing did not greatly alter the larva body. If ruptures were observed, the antigen release to the incubation media was not enhanced, and most of the antigenic content was retained inside the bodies of the larvae. The immunoblotting assay demonstrated that most of the antigens released, including the allergen Ani s 4, were resistant to pepsin. Freezing killed the larvae, but their survival was not compromised by acid treatment or pepsin digestion when kept chilled. All these findings support recommendations about freezing fish for consumption raw or undercooked to prevent human infection by A. simplex larvae. However, our data show that the antigenicity of the larvae is preserved after freezing and may explain why some sensitized patients develop symptoms after ingestion of infested frozen fish.

Anisakis antigens detected in fish muscle infested with Anisakis simplex L3.

Anisakis simplex is a fish parasite that is a public health risk to those consuming raw or poorly cooked marine fish and cephalopods because of the possibility of becoming infested with live larvae. In humans, penetration of the larvae into the gastrointestinal track can cause acute and chronic symptoms and allergic anisakiasis. Excretion and secretion products released by the larvae are thought to play a role in migration through the tissues and induce an immunoglobulin E-mediated immune response. The aim of this preliminary study was to detect parasite antigens and allergens in fish tissues surrounding the migrating larvae. Hake and anchovy fillets were artificially parasitized with Anisakis larvae and stored in chilled conditions for 5 days. Larvae were evaluated for fluorescence, fish muscle tissue was examined with transmission electron microscopy, and immunohistochemical reactions of two rabbit polyclonal antisera against a parasite crude extract and the allergen Ani s 4 were recorded. Larvae immediately migrated into the fish muscle, and no emission of bluish fluorescence was observed. Fish muscle areas in contact with the parasite showed disruptions in the structure and inclusion of granules within sarcomeres. Both parasite antigens and the Ani s 4 allergen were located in areas close to the larvae and where sarcomere structure was preserved. These findings indicate that parasite antigens and allergens are dispersed into the muscle and might cause allergic symptoms such as dyspnea, vomiting, diarrhea, urticaria, angioedema, or anaphylaxis in some individuals sensitive to A. simplex.

Trehalose catabolism enzymes in L3 and L4 larvae of Anisakis simplex.

The presence of trehalase and trehalose phosphorylase in L3 and L4 larvae of Anisakis simplex was demonstrated. The activity of trehalase and trehalose phosphorylase in L3 larvae was 6 and 10 times higher, respectively, than in L4 larvae. This suggests that trehalose metabolism is more important for L3 than LA larvae. Trehalases of L3 and L4 differ in their characteristics. The enzyme of L3 was present mainly in the lysosomes and cytosol, whereas in L4 the highest enzyme activity was measured in the lysosomal fraction. Trehalase activity was increased by 29% in L3 and 55% in L4 with the addition of Mg2+ (0.1 mmol). Tris inhibited trehalase in L3 larvae by 42% and in L4 by 25%. The enzymes differed in their reaction to EDTA, CaCl2, ZnCl2, and CH2ICOOH (all 0.1 mmol). High activity of trehalase from L3 larvae was measured within the pH range of 5.0 to 6.5, with an optimum pH of 6.1. The trehalase was a thermally tolerant enzyme from 25 C to 60 C. The enzyme lost half of its activity after preincubation without substrate above 75 C. The paper also discusses the similarities and differences in characteristics of trehalase from A. simplex larvae and presents the comparison to enzymes from other nematodes.

Acute gastric anisakiasis: an Italian experience.

Anisakidosis is a parasitic disease of the human gastrointestinal tract caused by ingestion of larvae of marine nematodes such as Anisakis spp. or, rarely, Pseudoterranova spp., present in raw or undercooked fish. We report the first series of gastric Anisakis infection (anisakiasis) from a single centre in Italy. In our department, we observed 3 cases, all in women who were urgently hospitalized following intense epigastric pain and vomiting, developed after the ingestion of raw fish. The patients underwent urgent gastroscopy within a few hours. In each, a worm was extracted from the gastric mucosa by means of biopsy forceps. This was followed by prompt clinical improvement. The worm was identified by its macroscopic and microscopic characteristics as an Anisakis spp. larva (L3). In 2 cases, laboratory tests revealed marked leukocytosis and eosinophilia in the peripheral blood 3-4 days after ingestion of the raw fish. The diagnosis of anisakiasis can be made by endoscopy, radiology and abdominal ultrasound, but is often made only at surgery. In the gastric form of the disease, urgent gastroscopy has both a diagnostic and a therapeutic role, because the worm can be removed by means of biopsy forceps.

[Investigation on the nematode of Hysterothylacium aduncum (Anisakidae) from Bohai Sea and Yellow Sea in China].

OBJECTIVE: To investigate Hysterothylacium aduncum (Anisakidae) infection in marine fishes from Bohai Sea and Yellow Sea. METHODS: Nematodes were collected from the digestive tract of fishes, fixed with hot 4% formalin and preserved in 70% ethanol for study. The specimens were cleared in lactophenol for light microscopical examination, and properly treated for scanning electron microscopy (SEM). RESULTS: Among the fishes examined, 14 out of 93 species (15.1%) were found infected by H. aduncum, with a higher prevalence in the fish of Lophius litulon (66.7%), Scomberomorus niphonius (47.5%), and Gadus macrocephalus (33.3%). H. aduncum infection was first recorded in elasmobranch-Raja smirnovi. Morphological differences of H. aduncum were observed, including the width of lateral alae and the length of intestinal caecum. CONCLUSION: H. aduncum in fishes of Bohai Sea and Yellow Sea in China may be a complex species, and its high prevalence in some fishes reminds the risk of anisakiasis by eating raw fishes.

Scanning electron microscopy of Anisakis larvae following different treatments.

Ingestion of fish parasitized with Anisakis larvae can produce infestation and/or allergy in consumers. Technological and food processing treatments have been applied to parasitized fish in order to kill the larvae and avoid the infestation; however, their influence on allergenicity has not been studied. Four lots of hake (Merluccius merluccius) steaks artificially parasitized with Anisakis larvae were subjected to two storage chilling (5 degrees C +/- 1 degrees C) and freezing (-20 degrees C +/- 1 degrees C) treatments and two food processing treatments of heat (final temperature 86.3 degrees C) and microwave (final temperature 66.9 degrees C) and studied by scanning electron microscopy, environmental scanning electron microscopy (ESEM) (acid [pH = 2] and water preparations), and emission of fluorescence. Anisakis larvae were resistant to acid conditions, remaining alive after treatment. Larvae in the heat- and microwave-treated lots presented coagulated and disrupted zones in the cuticle with release of fluids. The cylindrical shape changed to a dehydrated appearance mainly observed by ESEM. Fluorescence was only noticeable in the frozen larvae. Larvae without apparent changes, together with dehydrated ones, were observed by ESEM in the frozen lot; nevertheless, no disruptions in the cuticle were perceptible. Further studies are needed in order to elucidate if the changes observed in the cuticle reduce the resistance of the parasites to the action of gastric enzymes in the gastrointestinal tract and to determine the release of allergens to the flesh by the live larvae during chilled storage of the fish.

Interactions between ecto- and endoparasites in trout Salmo trutta.

Trout fry were experimentally infected with endoparasites (Anisakis sp.) and/or ectoparasites (Gyrodactylus derjavini). During the following 3 weeks the infection level of G. derjavini was significantly lowered in fish infected with live anisakids compared to fish injected with physiological saline, a corresponding amount of Anisakis protein sonicate or to untreated fish. Subsequent scanning electron microscopy (SEM) of recovered nematodes from the trout showed an extensive colonization of the worms with host macrophages. It is indicated that the activation of the fish immune system by infection with live anisakids influences the skin response of the host with a subsequent negative effect on the ectoparasites G. derjavini.

Immunofluorescent localization of intermediate filaments (IFs) in helminths using anti-mammalian IFs monoclonal antibody.

Intermediate filaments (IFs) make up the cytoskeleton of most eukaryotic cells. In vertebrates, a number of IF proteins have been identified, showing distributions unique to tissue or cell type. Information on helminth IFs is limited to some nematode species. To observe immunofluorescent localization of IFs in helminth tissues, we selected a murine hybridoma clone producing IgM antibody to multiple types of mammalian IF proteins and examined cross-reactivity to helminth proteins. The selected monoclonal antibody (HUSM-9) cross-reacted well with IFs from nematode species such as Toxocara canis, Dirofilaria immitis, Anisakis simplex, and Trichinella britovi; strong immunofluorescence on cryostat sections was detected in the hypodermis, cords, body muscle, smooth muscle of the uterus, and other epithelial structures. In platyhelminths, i.e., adult Schistosoma mansoni, larval Taenia taeniaeformis, adult Taenia crassiceps, and Echinococcus multilocularis protoscolex, the reactivity was weaker than in nematodes, and localized in the body wall muscle and subtegumental tissue. Western blotting of 8 M urea extracts of parasites with the antibody detected a pair of clear bands in nematodes but not in S. mansoni or the cestodes. These results might be explained by sparse distribution of IFs in platyhelminths, or low affinity of the used antibody to platyhelminth IF proteins, or both.

Intestinal anisakiasis: first reported case in Thailand.

A case of intestinal anisakiasis is reported. The patient came with the symptoms of acute abdominal obstruction. The diagnosis was obtained by identification of the parasite in the tissue sections of the resected segment of the small intestine. This case appears to be the first reported case in Thailand.