The response of Anisakis simplex (s. s.) to anthelmintics - Specific changes in xenobiotic metabolic processes.

Anisakiasis is a parasitic disease transmitted through the consumption of raw or undercooked fish and cephalopods that are infected with larvae of Anisakis simplex (sensu stricto) or Anisakis pegreffii. The purpose of this study was to investigate how A. simplex (s. s.) responds to the influence of anthelmintics such as ivermectin (IVM) and pyrantel (PYR). In vitro experiments were conducted using larvae at two developmental stages of A. simplex (s. s.) (L3 and L4) obtained from Baltic herring (Clupea harengus membras). Larvae were cultured with different concentrations of IVM or PYR (1.56, 3.125, and 6.25 µg/mL) for various durations (3, 6, 9, and 12 h) under anaerobic conditions (37 °C, 5% CO2). The gene expression of actin, ABC transporter, antioxidant enzymes, γ-aminobutyric acid receptors, and nicotinic acetylcholine receptors, as well as the oxidative status were analyzed. The results showed that A. simplex (s. s.) L3 stage had lower mobility when cultured with PYR compared to IVM. The analysis of relative gene expression revealed significant differences in the mRNA level of ABC transporters after treatment with IVM and PYR, compared to the control group. Similar patterns were observed in the gene expression of antioxidant enzymes in response to both drugs. Furthermore, the total antioxidant capacity (TAC) and glutathione S-transferase (GST) activity were higher in the treatment groups than in the control group. These findings suggest a relationship between the expression of the studied genes, including those related to oxidative metabolism, and the effectiveness of the tested drugs.

Increasing intensities of Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878) larvae with weight and sea age in returning adult Atlantic salmon, Salmo salar L., of coastal waters of Norway.

Ninety wild Atlantic salmon, Salmo salar L., (1.5-10.3 kg) were caught in the Namsen Fjord near the mouth of River Namsen, mid-Norway, and examined for the presence and distribution of Anisakis simplex (Rudolphi, 1809 det. Krabbe, 1878) larvae by digestion of the viscera and muscles in a pepsin/HCl solution. All salmon were migrating spawners after 1-4 years of feeding in the Atlantic Ocean. All 90 Atlantic salmon had A. simplex larvae in the viscera, and all, except two, had A. simplex larvae in the musculature. The number of A. simplex larvae in each fish varied between 3 and 181, and the total mean number of nematode larvae was 44.5. The intensity of A. simplex larvae was positively correlated with increasing weight and sea age of the host. However, the proportion of larvae in the muscle fillets decreased with increasing host weight and sea age. Atlantic salmon females had more A. simplex larvae than males. In all the fish examined, 70.2% of the A. simplex larvae were found in the viscera and 29.8% in the musculature. The majority (93%) of the larvae in the musculature occurred in the hypaxial sections anterior to the anus. As A. simplex larvae commonly occur in the musculature of wild Atlantic salmon, consumption of unfrozen, raw or semi-raw musculature represents a risk for humans developing anisakiasis.

Shotgun Proteomics for L3 and L4 Anisakis simplex Development Stages.

Anisakis simplex s.s. is a parasitic nematode that causes anisakiasis in humans. L3 stage larvae, which are present in many fish species and cephalopods all over the globe, might be consumed and develop occasionally into the L4 stage but cannot reproduce. Anisakiasis is an emerging health problem and economic concern. In recent years, proteomic methods have gained greater acceptance among scientists involved in parasitology and food science. According to that, here, we present tandem mass tag (TMT)-based shotgun proteomics to define differences in proteomic composition between L3 and L4 development stages of A. simplex s.s.

Expression and functionality of allergenic genes regulated by simulated gastric juice in Anisakis pegreffii.

To better understand the molecular mechanisms underlying allergens and parasite immunity and discover the stage-enriched gene expression of fish-borne zoonotic nematodes in the stomach, we used RNA-seq to study the transcriptome profiles of Anisakis pegreffii (Nematoda: Anisakidae, AP) in simulated gastric juice. Mobile L3 larvae were incubated in simulated medium at 37 °C in 5% CO2 (AP-GJ) and the control group larvae were collected in PBS under the same conditions (AP-PBS). We found that the sequences of A. pegreffii were highly similar to Toxocara canis sequences. Among the transcripts, there would be 138 up-regulated putative genes and 251 down-regulated putative genes in AP-GJ group. Several lipid binging-related genes were more highly expressed in AP-GJ larvae. Moreover, 17 allergen genes were up-regulated and 29 were down-regulated in AP-GJ larvae. Eleven allergen genes belonged to one or more of the following three categories: biological process, cellular component, and molecular function. According to KEGG analysis, the main pathways that were represented included protein processing in transcription, immune system, cancer, and infectious disease. In particular, the most significant changes in the expression of parasite-derived allergen products occurred in AP-GJ larvae. This study helps us to extend our understanding of the biology of the fish-borne zoonotic parasite A. pegreffii and could be helpful for more precise risk assessment and providing guidelines for allergic consumers.

Advances in Omic Studies Drive Discoveries in the Biology of Anisakid Nematodes.

Advancements in technologies employed in high-throughput next-generation sequencing (NGS) methods are supporting the spread of studies that, combined with advances in computational biology and bioinformatics, have greatly accelerated discoveries within basic and biomedical research for many parasitic diseases. Here, we review the most updated "omic" studies performed on anisakid nematodes, a family of marine parasites that are causative agents of the fish-borne zoonosis known as anisakiasis or anisakidosis. Few deposited data on Anisakis genomes are so far available, and this still hinders the deep and highly accurate characterization of biological aspects of interest, even as several transcriptomic and proteomic studies are becoming available. These have been aimed at discovering and characterizing molecules specific to peculiar developmental parasitic stages or tissues, as well as transcripts with pathogenic potential as toxins and allergens, with a broad relevance for a better understanding of host-pathogen relationships and for the development of reliable diagnostic tools.

Occurrence of larval anisakids in horse mackerel (Trachurus trachurus) caught in Portuguese waters.

The third-stage larvae (L3) of the Anisakidae family are parasitic nematodes with zoonotic impact and are frequently encountered in the organs and musculature of various fish intended for human consumption. Since Anisakis simplex (s.s.) and A. pegreffii are the major aetiological agents of human disease, this study aims to combine the morphological and molecular data on the recovered anisakid larvae to contribute to a simplified morphological distinction of those species and conducted a survey of anisakid larvae infection in horse mackerel (Trachurus trachurus). Here, 116 horse mackerel caught in Portuguese waters were analysed for the presence of L3 of anisakids, and 3148 larvae were collected, of which only 30% were retrieved during visual inspection. As such, visual inspection does not appear to be very effective in anisakid detection. A prevalence of 84.5% of infected fish was found, and the mean intensity and mean abundance were 32.1 and 27.1 parasites per fish, respectively. The morphological and molecular analyses of 196 L3 randomly chosen from the total sample of parasites demonstrated the presence of L3 of mostly Anisakis spp., with only one L3 of Hysterothylacium aduncum. Relative frequencies of 62.9% for A. pegreffii and 37.1% for A. simplex (s.s.) were obtained. The morphometry differences between these two sibling species were evaluated, and the results demonstrated significant differences between the length of the ventriculus and the length of the oesophagus. Precisely, A. simplex (s.s.) has a longer oesophagus and ventriculus than A. pegreffii. As such, these differences may be used to distinguish the two species through morphological analysis.

A multi-restriction fragment length polymorphism genotyping approach including the beta-tubulin gene as a new differential nuclear marker for the recognition of the cryptic species Anisakis simplex s.s. and Anisakis pegreffii and their hybridization events.

The detection of Anisakis simplex s.s./A. pegreffii putative hybrids has been a controversial issue in spite of the fact that natural hybridization is an extended process across free living and parasitic organisms. Differential traits of biomedical and ecological importance, such as invasive and allergenic potential have been demonstrated in both cryptic species. Therefore, in this work, we discuss about the potential for hybridization between these anisakid species in sympatric zones, implementing a multi-marker Restriction fragment length polymorphism (RFLP) genotyping approach based on the ribosomal DNA internal transcribed spacer 1 (ITS1), the mitochondrial cytochrome C oxidase 2 (Cox-2) and a new nuclear marker, the highly conserved ß-tubulin gene (ß-TUB). The two cryptic species differed at least in 7 bp in the ß-TUB gene and some larvae with heterozygous genotypes at the 7 diagnostic nucleotide positions were found. Taxonomic, population and genealogical analyses served to support the occurrence of hybridization between both species. Predicted restriction endonucleases enzymes were assayed for Cox-2 and ß-TUB markers. The implemented multi-marker PCR-RFLP allowed us to detect the two pure parental species, F1 hybrids, hybrid backcrossed progeny and individuals with nuclear-mitochondrial discordance, being a useful, simple and reproducible procedure in any laboratory for epidemiological studies.

Anisakis spp. in fishery products from Japanese waters: Updated insights on host prevalence and human infection risk factors.

The nematodes of the genus Anisakis are among the most relevant parasitic hazards in fishery products since they are responsible for human infection and allergy cases. In a food safety and epidemiological perspective, several marine hosts from different locations around Japan were examined to characterize the parasitism of Anisakis larvae. Chum salmon (Oncorhynchus keta) and Alaska pollock (Gadus chalcogrammus) showed the highest overall prevalence (100%), followed by blue mackerel (Scomber australasicus) (97.5%), Pacific cod (Gadus macrocephalus) (80%), chub mackerel (Scomber japonicus) (60.1%), Japanese flying squid (Todarodes pacificus) (17%) and Japanese pilchard (Sardinops sagax melanostictus) (2%). In Pacific krill (Euphausia pacifica), apart from one Hysterothylacium aduncum larva, no Anisakis specimens were detected. Anisakis simplex sensu stricto was molecularly identified (PCR-RFLP) for the first time in Japanese flying squid and Japanese pilchard distributed in the Northwestern Pacific ocean. That was the most frequent parasitic species detected followed by A. pegreffii, mostly in the western areas of Japan, hybrid genotypes between the two sibling species as well as A. typica and A. berlandi. Surprisingly, A. simplex s.s. was the most abundant species in one batch of chub mackerel from the East China Sea and A. pegreffii was the main species found in one batch from the Pacific coast of Aomori, which seems to indicate that the ranges of these two sibling species might be more variable than previously thought.

First case of human anisakiasis in Poland.

Consumption of raw or inadequately processed marine fish may result in anisakidosis - a zoonotic disease caused by larvae of the parasitic nematodes of the family Anisakidae (anisakiasis when caused by members of the genus Anisakis (Nematoda: Anisakidae)), commonly found in a variety of marine fish species all over the world. Most cases of anisakidosis have been detected in the residents of Japan and South Korea, which results from the tradition of eating raw and semi-raw fish dishes. However, the disease is now increasingly often diagnosed in other parts of the world, including Europe (mainly in Spain and Italy). In Poland, no cases of human infection with anisakid nematodes have been detected so far. In this study, we report the first case of gastric anisakiasis in Poland, in a 59-year-old female patient, after eating raw Atlantic salmon (Salmo salar). The parasite was identified as the third-stage larva of Anisakis simplex sensu stricto on the basis of morphology and molecular analysis. The larva was still alive and causing pain until it was removed, which occurred more than 5 weeks after infection. The described case prove that anisakiasis should be considered as a potential cause of gastrointestinal tract ailments following the consumption of seafood in countries where no cases of this zoonosis have been reported to date.

El ciclo evolutivo de parásitos de la familia anisakidae. Hacia una prospectiva de medidas sanitarias de control / The evolutionary cycle of parasites of the anisakidae family. towards a prospective of sanitary control measures

Las larvas de nematodos en los peces, generalmente corresponde a especies de la familia Anisakidae, son gusanos redondos, sin segmentación; con hospedadores intermediarios y definitivos y un huésped accidental que es el humano, en quién va producir una enfermedad parasitaria del tacto digestivo, mundialmente conocida como anisakiasis, asociada a reacciones de hipersensibilidad debido a los alérgenos del parásito. La presencia de estos parásitos en los productos de la pesca, deberá ser controlada con medidas preventivas establecidas en la legislación sanitaria de países; estableciendo profilaxis, medidas higiénicas como consumir el pescado cocido, o sometido previamente a congelación a -20°C por 48 a 72 horas, para prevenir la enfermedad. Cuando enfocamos hacia una prospectiva de medidas sanitarias de control preventivo, se plantea el establecimiento de un plan de requerimientos de alimentos seguros, basado en el análisis de riesgos y control de puntos críticos (HACCP), constituido por un paquete de documentos escritos basados en los principios de seguridad de alimentos; que contendrá: el análisis de riesgos; controles preventivos; programas en la cadena de suministros; delineamiento de los procedimientos para ser seguidos por monitoreo, acciones correctivas y verificación. Estará basado en las obligaciones que se puedan establecer bajo jurisdicción regulatoria para el pescado, en cuanto a la pesca o captura, manipulación a bordo o en la orilla y mecanismos de conservación hasta el expendio; que dé lugar a un manual de buenas prácticas de manufactura, análisis de riesgo y controles preventivos de riesgos para la regulación de alimentos de origen marino para consumo humano

The larvae of nematodes in fish generally correspond to species of the Anisakidae family, they are round worms, without segmentation; with intermediate and definitive hosts and an accidental host that is human, in whom it will produce a parasitic disease of the digestive tract, worldwide known as anisakiasis, associated with hypersensitivity reactions due to parasite allergens. The presence of these Parasites in fishery products should be controlled with preventive measures established in the sanitary legislation of countries; establishing prophylaxis, hygienic measures such as consuming the cooked fish, or previously subjected to freezing at -20 ° C for 48 to 72 hours to prevent the disease. When we focus on a prospective of preventive control sanitary measures, the establishment of a plan for safe food requirements based on risk analysis and control of critical points (HACCP), constituted by a package of written documents based on the principles, is considered food safety; which will contain: risk analysis; preventive controls; programs in the supply chain; delineation of the procedures to be followed by monitoring, corrective actions and verification. It will be based on the obligations that can be established under the regulatory jurisdiction for fish, in terms of fishing or capture, handling on board or on the shore and conservation mechanisms up to the sale; that results in a manual of good manufacturing practices, risk analysis and preventive risk controls for the regulation of food of marine origin for human consumption

A Case Report of Adhesional Small Bowel Obstruction Caused by Extraintestinal Anisakiasis.

BACKGROUND: Small bowel obstruction (SBO) is a common diagnosis made in the emergency department (ED). We present a case with an unusual underlying cause of SBO: extraintestinal infection with an Anisakis roundworm. CASE REPORT: A healthy young woman with no prior abdominal surgery presented with epigastric abdominal pain, nausea, and anorexia 1 day after eating a raw oyster. Laboratory studies were significant for 14% eosinophilia. Initial abdominal computed tomography (CT) showed small bowel inflammation and small-volume ascites. After discharge home, she returned on day 14 of illness with a closed-loop SBO, to which she was predisposed by an adhesion formed in association with an eosinophilic abscess containing an Anisakis roundworm. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Anisakiasis is an uncommon cause of common symptoms with which patients may present to EDs. The diagnosis should be considered in patients presenting with abdominal pain and recent ingestion of raw seafood, with suspicion raised further by the presence of focal gastric or small bowel inflammation and ascites on abdominal CT. Extraintestinal anisakiasis can cause inflammation leading to intraabdominal adhesions, a sequela of which is small bowel obstruction. If suspicion for gastric or intestinal anisakiasis is high, treatment with endoscopic removal or albendazole may be initiated.

Gastro-allergic anisakiasis: The first case reported in Colombia and a literature review / Anisakiasis gastro-alérgica, primera descripción de un caso en Colombia y revisión bibliográfica

Anisakiasis is a zoonotic parasitic disease caused by consumption of raw or undercooked fish or seafood infected with nematodes of the Anisakis, Pseudoterranova or Contracaecum genera. Here, we describe the first case of anisakiasis in Colombia and summarize the available literature. A 52-year-old female with a history of abrupt-onset sharp epigastric pain, nausea, vomit, diarrhea, and urticaria following fish consumption consulted the health service. The physical examination revealed moderate tenderness of the epigastric region; the laboratory evaluation showed leukocytosis and a simple X-ray and ECG showed no abnormalities. The diagnosis was made by endoscopic examination, which revealed a thickened gastric wall and a moving larval worm. An Anisakis larva was found and extracted endoscopically, which relieved the pain of the patient. Clinically, anisakiasis may present as a gastric, intestinal, extragastrointestinal or allergic disease. Diagnosis and treatment of anisakiasis are made by a dietary history, direct visualization and endoscopic extraction of possible larvae, which is the only effective therapy.

La anisakiasis es una enfermedad parasitaria zoonótica causada por el consumo de pescados o mariscos crudos o poco cocidos infectados con nematodos de los géneros Anisakis, Pseudoterranova y Contracaecum. Se describe el primer caso de anisakiasis en Colombia y se resume la literatura médica disponible. Una mujer de 52 años de edad consultó por dolor epigástrico agudo de inicio abrupto, náuseas, vómitos, diarrea y urticaria después de consumir pescado. El examen físico reveló sensibilidad moderada en el epigastrio. El examen de laboratorio evidenció leucocitosis, en tanto que la radiografía simple y el electrocardiograma no reflejaron ninguna anormalidad. El diagnóstico se hizo mediante una endoscopia de vías digestivas altas, la cual reveló engrosamiento de la pared gástrica y un parásito en movimiento. Se encontró una larva de Anisakis y se la extrajo por endoscopia, lo que alivió el dolor de la paciente. Clínicamente, la anisakiasis puede presentarse como una enfermedad gástrica, intestinal, en otros sistemas o alérgica. El diagnóstico se hace con base en la elaboración del historial alimentario del paciente y la visualización directa de las larvas; el único tratamiento efectivo consiste en su extracción endoscópica.

Genome-wide analysis of Anisakis simplex sensu lato: the role of carbohydrate metabolism genes in the parasite's development.

Anisakis simplex sensu lato is a parasitic nematode which can cause gastric symptoms and/or allergic reactions in humans who consume raw and undercooked fish. Anisakiasis poses a growing health problem around the globe because it causes non-specific symptoms and is difficult to diagnose. This genome-wide study was undertaken to expand our knowledge of A. simplex s.l. at the molecular level and provide novel data for biological and biotechnological research into the analyzed species and related nematodes. A draft genome assembly of the L3 stage of A. simplex s.l. was analyzed in detail, and changes in the expression of carbohydrate metabolism genes during the parasite's life cycle were determined. To our knowledge, this is the first genome to be described for a parasitic nematode of the family Anisakidae to date. We identified genes involved in parasite-specific pathways, including carbohydrates metabolism, apoptosis and chemo signaling. A total of 7607 coding genes were predicted. The genome of A. simplex s.l. is highly similar to genomes of other parasitic nematodes. In particular, we described a valuable repository of genes encoding proteins of trehalose and glycogen metabolism, and we developed the most comprehensive data set relating to the conversion of both saccharides which play important roles during the parasite's life cycle in a host environment. We also confirmed that trehalose is synthesized at the expense of glycogen. Trehalose anabolism and glycogen catabolism were the predominant processes in stages L4 and L5, which could confirm our and other authors' previous reports that trehalose is synthesized at the expense of glycogen. The A. simplex s.l. genome provides essential data for post-genomic research into the biology of gastrointestinal and allergic anisakiasis in humans and the biology of other important parasitic helminths.

Anisakiasis gastro-alérgica, primera descripción de un caso en Colombia y revisión bibliográfica / Gastro-allergic anisakiasis: The first case reported in Colombia and a literature review

Resumen La anisakiasis es una enfermedad parasitaria zoonótica causada por el consumo de pescados o mariscos crudos o poco cocidos infectados con nematodos de los géneros Anisakis, Pseudoterranova y Contracaecum. Se describe el primer caso de anisakiasis en Colombia y se resume la literatura médica disponible. Una mujer de 52 años de edad consultó por dolor epigástrico agudo de inicio abrupto, náuseas, vómitos, diarrea y urticaria después de consumir pescado. El examen físico reveló sensibilidad moderada en el epigastrio. El examen de laboratorio evidenció leucocitosis, en tanto que la radiografía simple y el electrocardiograma no reflejaron ninguna anormalidad. El diagnóstico se hizo mediante una endoscopia de vías digestivas altas, la cual reveló engrosamiento de la pared gástrica y un parásito en movimiento. Se encontró una larva de Anisakis y se la extrajo por endoscopia, lo que alivió el dolor de la paciente. Clínicamente, la anisakiasis puede presentarse como una enfermedad gástrica, intestinal, en otros sistemas o alérgica. El diagnóstico se hace con base en la elaboración del historial alimentario del paciente y la visualización directa de las larvas; el único tratamiento efectivo consiste en su extracción endoscópica.

Abstract Anisakiasis is a zoonotic parasitic disease caused by consumption of raw or undercooked fish or seafood infected with nematodes of the Anisakis, Pseudoterranova or Contracaecum genera. Here, we describe the first case of anisakiasis in Colombia and summarize the available literature. A 52-year-old female with a history of abrupt-onset sharp epigastric pain, nausea, vomit, diarrhea, and urticaria following fish consumption consulted the health service. The physical examination revealed moderate tenderness of the epigastric region; the laboratory evaluation showed leukocytosis and a simple X-ray and ECG showed no abnormalities. The diagnosis was made by endoscopic examination, which revealed a thickened gastric wall and a moving larval worm. An Anisakis larva was found and extracted endoscopically, which relieved the pain of the patient. Clinically, anisakiasis may present as a gastric, intestinal, extragastrointestinal or allergic disease. Diagnosis and treatment of anisakiasis are made by a dietary history, direct visualization and endoscopic extraction of possible larvae, which is the only effective therapy.

Effectiveness of five flavored Tunisian olive oils on Anisakis larvae type 1: application of cinnamon and rosemary oil in industrial anchovy marinating process.

BACKGROUND: Anisakidosis is caused by the ingestion of raw or undercooked fish or cephalopods containing viable Anisakis larvae. Several natural extracts, oils, essential oils, and their compounds have been tested against Anisakis. In this study the effectiveness of Tunisian olive oil with different spices or plants (cardamom, cinnamon, ginger, laurel, and rosemary) was tested against Anisakis larvae type 1. RESULTS: For the in vitro test, larvae were submerged separately in the oils mentioned above and observed to check viability. Cinnamon oil was the most effective against parasites with lethal time (LT) scores being LT50 = 1.5 days and LT100 = 3 days, followed by rosemary. Laurel, cardamom, and ginger oils were less effective. For the ex vivo experiment, cinnamon, and rosemary oils were tested in anchovy fillets, previously artificially parasitized. Cinnamon was the most effective against parasites (dead after 4 days) as compared to rosemary (7 days). CONCLUSION: The use of cinnamon and rosemary-flavored olive oil in the industrial marinating process can be considered as an efficient alternative to the freezing process required by European Regulation EC No 853/2004 to devitalize Anisakis. © 2019 Society of Chemical Industry.

Anisakid Larvae from Anchovies in the South Coast of Korea.

Anisakiasis (anisakidosis) refers to a foodborne zoonosis caused by ingesting raw or undercooked marine fish or cephalopods infected with anisakid larvae. The present study was performed to investigate the prevalence of anisakid larvae in anchovies (Engraulis japonica) purchased from 2 local markets in Gyeongsangnam-do, the Republic of Korea (=Korea), during 2018-2019. Anchovies were transported to our laboratory and examined by pepsin-HCl artificial digestion technique followed by microscopic observations and molecular analyses. The overall prevalence of anisakid larvae was 19.5% (39/200), from which a total of 51 larvae (av. 1.3 larvae/infected anchovy) were recovered. Sequencing of the larvae targeting the ITS region, including ITS1, 5.8S rRNA, and ITS2 genes confirmed the species of larvae as Anisakis pegreffii (54.9%; 28/51), Hysterothylacium sinense (23.5%; 12/51), and Hysterothylacium aduncum (21.5%; 11/51). The results suggested that anchovies could be a potential source of human anisakiasis in Korea.

Comparative transcriptome analyses of the third and fourth stage larvae of Anisakis simplex (Nematoda: Anisakidae).

We analyzed transcriptome profiles of Anisakis simplex (Nematoda: Anisakidae) 3rd (ASL3) and 4th larvae (ASL4) obtained by RNA-seq, to understand the molecular pathways linked to parasite survival and discover stage-enriched gene expressions. ASL3 were collected from chum salmon and ASL4 were obtained by in vitro culture. Whole transcriptome sequencing was conducted with Illumina sequencer, and de novo assembly was conducted. 47,179 and 41,934 genes were expressed in ASL3 and ASL4 transcriptomes. Of them, 17,633 were known and 29,546 were unmapped sequence for ASL3. 17,126 were known and 24,808 were unmapped sequence for ASL4. Polyubiquitins-related genes and collagen-related genes were the most abundantly expressed in ASL3 and ASL4. Mitochondrial enzyme-related genes were highly expressed both in ASL3 and ASL4. Among the transcripts, 675 were up-regulated in ASL3, while 1015 were up-regulated in ASL4. Several protease-related and protein biosynthesis-related genes were highly expressed in ASL3, all of which are thought to be crucial for invading host tissues. Collagen synthesis-related genes were highly expressed in ASL4, reflecting active biosynthesis of collagens during molting process. This information will extend our understanding of biology of the fish-borne zoonotic parasite A. simplex.

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.

A Multicenter Study of IgE Sensitization to Anisakis simplex and Diet Recommendations.

BACKGROUND: Allergy to Anisakis simplex (s.) is spreading due to the increased consumption of raw, smoked or marinated fish. In man, Anisakis s. can directly attack the gastrointestinal mucosa, provoking a parasitosis known as anisakiasis, or giving rise to the formation of IgE and, finally, inducing IgE-mediated reactions like urticaria, angioedema and anaphylactic shock. During recent years, a dietary approach to Anisakis s. infestation has also been addressed. METHODS: A total of 620 patients with urticaria, angioedema, or both and a history of anaphylaxis following consumption of raw, smoked or marinated fish were recruited, evaluated for specific IgE levels to Anisakis s. and subjected to Skin Prick test. Following 18 month fish-free diet, patients were reevaluated at 6, 12 and 18 months, respectively. Patients undergoing diet were selected among those who had a clinical history with multiple accesses to first aid. RESULTS: After 6-month fish-free diet, we recorded an improvement of symptoms and a remarkable reduction of specific IgE levels. The extension of the diet over 6 months in some cases resulted in a further reduction of specific IgE levels. CONCLUSION: Data obtained confirm the importance of a fish-free diet in patients with severe symptoms since a new antigenic exposure coincides with a relapse of symptoms and increased IgE levels. This last point should be kept in mind and carefully evaluated in patients at risk for anaphylaxis or angioedema.