Intestinal Nematode Research Articles

Production of recombinant 14-3-3 protein and determination of its immunogenicity for application in serodiagnosis of strongyloidiasis.

Strongyloides stercoralis is the fourth most important intestinal nematode worldwide. The parasite load and larvae count are often low, thus conventional methods are not sufficiently sensitive to detect the infection. In this study we developed an immunoglobulin G-based enzyme-linked immunosorbent assay (ELISA) method to detect antibodies against S. stercoralis 14-3-3 protein in patients' sera. S. stercoralis RNA was extracted and following complementary DNA synthesis, the 708-bp fragment of 14-3-3 protein was amplified by polymerase chain reaction and cloned into the pET28a+ expression vector. The 30-kDa recombinant 14-3-3 protein was expressed in Escherichia coli BL21 (DE3) cells and purified by affinity chromatography. Finally, its immunoreactivity was assessed by indirect ELISA and western blotting. The S. stercoralis 14-3-3 gene was successfully amplified and cloned into an expression vector. The 30-kDa recombinant protein was purified by affinity chromatography. An ELISA developed in-house detected infected patients' sera with 96% sensitivity. We concluded that the recombinant 14-3-3 protein has enough sensitivity and specificity for detection of strongyloidiasis in human sera and could be applied for serodiagnosis.

Intestinal nematode infection exacerbates experimental visceral leishmaniasis.

Leishmania donovani exposure often results in subclinical infection in immunocompetent individuals, and the factors dictating development of visceral leishmaniasis (VL) are not known. Infection with intestinal worms skew immunity towards type 2 and regulatory responses, thereby theoretically increases susceptibility to intracellular infections controlled by type 1 responses. Here we have tested how chronic infection with the intestinal nematode Heligmosomoides polygyrus affected immunity to a secondary infection with Ldonovani. We found that mice infected with Hpolygyrus displayed higher Leishmania burden in liver and spleen compared to worm-free animals. This increased infectious load was accompanied by reduced leucocyte infiltration and nos2 transcription in livers and increased il4 and il10 transcription in spleens. Collectively, these data show that chronic infection with intestinal nematodes skew immune responses in a way that may favour development of VL.

The Global Burden of Disease of Zoonotic Parasitic Diseases: Top 5 Contenders for Priority Consideration.

With the rise of global migration, international trade, and global environmental challenges such as climate change, it is not surprising that the interactions between humans and other animals are shifting. Salient infectious diseases, such as malaria and HIV (which have high burdens of disease), attract sophisticated public health frameworks and funding from global/regional organisations, such as the WHO. This unfortunately detracts attention from the many emerging zoonoses that fall under the radar as neglected tropical diseases (NTDs). This review considers the available literature and the attribution of burden of disease to the most insidious NTDs and recommends which five are deserving of policy prioritisation. In line with WHO analyses of NTDs, intestinal nematode infections, leishmaniasis, schistosomiasis, and lymphatic filariasis should be prioritised, as well as the burden of disease of cryptosporidiosis, which is largely underestimated. Both monitoring and treatment/prevention control methods for cryptosporidiosis are suggested and explored.

Strongyloides stercoralis Hyperinfection Syndrome as a Cause of Fatal Gastrointestinal Hemorrhage.

ABSTRACTStrongyloides stercoralis is a small intestinal nematode that is widespread in regions with poor sanitation. We present a 57-year-old man from Colombia who was undergoing corticosteroid therapy for a meningioma who presented after neurosurgery with abdominal pain and a profound gastrointestinal (GI) bleed. The patient underwent an esophagogastroduodenoscopy (EGD), an attempted embolization, and an exploratory laparotomy to remove the necrosed duodenum. His pathology examination revealed Strongyloides infection of the duodenum, and he died of profound blood loss. This rare diagnosis displays the importance of screening patients at a high risk of Strongyloides infection before starting glucocorticoid therapy.

Parasitological contamination with eggs Ascaris spp., Trichuris spp. and Toxocara spp. of dehydrated municipal sewage sludge in Poland

The objective of the present study was to evaluate the contamination of sewage sludge produced by municipal waste treatment plants in Poland by viable eggs of intestinal parasites of the genera Ascaris, Toxocara and Trichuris (ATT). Ninety-two municipal, mechanical-biological sewage treatment plants located within Poland were selected. These plants belonged to types of agglomerations: group 0 (large), group 1 (medium), group 2 (smaller) and group 3 (small). Samples were collected at the final stage of sewage treatment after the addition of flocculent to sludge, followed by dehydration. The samples were examined by a method adjusted to examine sewage sludge dehydrated using polyelectrolytes. The viability of the isolated eggs was evaluated based on incubation in a moist chamber. Live eggs of intestinal nematodes were found in 99% of samples. Most samples were contaminated by the eggs of Ascaris spp. (95%) and Toxocara spp. (96%). However, Trichuris spp. eggs were detected in 60% of samples. The mean number of eggs in 1 kg of dry mass (eggs/kg d.m.) was 5600 for Ascaris, 3700 for Toxocara and 1100 for Trichuris. The highest number of ATT eggs was detected in samples from sewage treatment plants located in south-eastern and central Poland. The highest number of ATT eggs was found in sewage sludge produced in large sewage treatment plants (agglomeration Groups 0 and 1), with mean values of 15,000 and 8900 eggs/kg d.m. The present study is the first parasitological investigation conducted on a large number of samples (92 samples) taken from various types of municipal sewage treatment plants located throughout Poland (16 regions) after the common introduction of polyelectrolytes during sewage sludge dehydration. The results of this study indicate that sludge produced in municipal sewage treatment plants is highly contaminated with parasite eggs.

Ultrasonography for early diagnosis of Toxocara canis infection in puppies.

Toxocara canis is one of the most common intestinal parasites in dogs and represents a highly infectious zoonotic parasite worldwide. Adult worms live in the bowel of dogs, and infections in puppies are commonly acquired transplacentally. The biology of the parasite and the commonly used diagnostic method, based on faecal examination, often prevent an early diagnosis of toxocariasis in puppies. Ultrasonographic diagnosis of intestinal ascariasis could be a feasible alternative method to diagnose T. canis infection in puppies during the prepatent period. The present study evaluated the diagnostic accuracy of ultrasonography for the diagnosis of intestinal toxocariasis in new-born puppies during the prepatent period. Fifty-four new-born puppies were prospectively recruited in the study. Each dog underwent intestinal ultrasonography and copro-microscopic examination every 5days, starting from the 10th day post-birth. Intestinal ultrasonography visualized adult T. canis nematodes in the puppies' small intestine from the 10th day post-birth. On the 15th day after birth, ultrasonography showed 100% specificity and 85.4% sensitivity in diagnosing T. canis infection, despite negative results deriving from the copro-microscopic examination performed at the same time point. Our results showed that ultrasonography can be used as test for early diagnosis of T. canis infection in new-born puppies during the prepatent period. Early ultrasonographic diagnosis of T. canis infection in puppies could help control the disease in dogs and reduce the zoonotic risk for the human population.

Strongyloides Hyperinfection Syndrome in an Immunosuppressed Patient

Strongyloides stercoralis is an intestinal nematode which is endemic in tropical and subtropical countries. The global prevalence of Strongyloides is unknown. Strongyloidiasis is found more frequently in the socioeconomically disadvantaged, in institutionalized populations, and in rural areas. The spectrum of disease varies. It may cause asymptomatic infection, mild eosinophilia or hyperinfection syndrome in the most severe form. Here we reported a case of Strongyloides hyperinfection syndrome in an immunosuppressed patient. This patient is a 54-year-old man with myasthenia gravis on long term azathioprine and prednisolone. He presented with fever associated with diarrhoea and was in septic shock. His blood culture was positive for Klebsiella pneumoniae. Strongyloides stercoralis larvae were detected in his sputum and stool sample. He was diagnosed to have Strongyloides hyperinfection and was treated with subcutaneous ivermectin. He recovered well. Our case demonstrated the association of Strongyloides hyperinfection with superimposed gram-negative sepsis as a consequence of prolonged immunosuppression. A high index of suspicion is needed in approaching patient with risk factors of hyperinfection syndrome.

Monitoring of Intestinal Nematodoses of Dogs in the Kabardino-Balkarian Republic and the Test Results of the New Drug Avertfen Powder

In the constituent entities of the Russian Federation, the most common nematodes are toxocarosis, ankylostomosis, uncinariosis, toxoascariosis, which occur in dogs with an EI of 50-100%. The goal is to monitor intestinal nematodes in dogs in Kabardino-Balkaria and to test the effectiveness of the new drug Avertfen powder in mixed invasion of intestinal nematodes in dogs. Studies have shown that intestinal nematodoses of dogs in the form of mono and mixed invasions are widespread in the Kabardino-Balkarian Republic with a total EI of 78.6%. Associative invasion caused by a tetrade of intestinal nematodes (Toxocara canis, Ancylostoma caninum. Toxascaris leoninae, Uncinaria stenocephala) was observed mainly with EI = 38,0% with an intensity of 169.7; 132.5; 94.8; 147,3ekz. /head. In the group of dogs infected with the mixed invasion Toxocara canis, Ancylostoma caninum., Toxascaris leoninae, Uncinaria stenocephala, the new drug Avertfen powder in a dose of 15mg/kg body weight had EE and IE - 100%. At the same time, on the 7th day, deworming of eggs and larvae of intestinal nematodes was not detected in feces. This dose of Avertfen powder should be recognized as an effective therapeutic dose.

Chamomile Methanolic Extract Mitigates Small Bowel Inflammation and ROS Overload Related to the Intestinal Nematodes Infection in Mice.

Chamomile (Matricaria recutita L.) is a plant which has been reported to be effective in treating several parasitic and digestive diseases. The present study was conducted to evaluate the anthelmintic activity of chamomile methanolic extract (CME). In vitro, the anthelmintic activities of CME were investigated on the L3 larvae of Heligmosomoides polygyrus in comparison to albendazole. In vivo, Swiss albino mice were infected with infective third (L3) larval stage of H. polygyrus by intragastric administration. Moreover, the effect of CME and albendazole on worm eggs, adult worms, serum cytokine production, and oxidative stress was studied. All used doses of CME showed a potent anthelmintic activity both in vitro and in vivo and the effect being similar to treatment with albendazole. Moreover, H. polygyrus infestation was accompanied by an intestinal oxidative stress status characterized by an increased lipoperoxidation, a depletion of antioxidant enzyme activity, as well as an overload of hydrogen peroxide. We have also recorded an increase of pro-inflammatory mediator (TNF-α, IL-6, and IL-1β) levels after treatment with CME (14 ± 0.8; 41 ± 2; 58 ± 4 pg/mg protein, respectively, with the concentration 800 mg/kg, body weight) when compared with infected control mice (20 ± 1; 59 ± 2, and 83 ± 4 pg/mg protein, respectively). However, extract treatment alleviated all the deleterious effects associated with H. polygyrus infection. These findings suggest that CME can be used in the control of gastrointestinal helminthiasis and associated oxidative stress.

Preclinical toxicity and pharmacokinetics of a new orally bioavailable flubendazole formulation and the impact for clinical trials and risk/benefit to patients.

BackgroundFlubendazole, originally developed to treat infections with intestinal nematodes, has been shown to be efficacious in animal models of filarial infections. For treatment of filarial nematodes, systemic exposure is needed. For this purpose, an orally bioavailable amorphous solid dispersion (ASD) formulation of flubendazole was developed. As this formulation results in improved systemic absorption, the pharmacokinetic and toxicological profile of the flubendazole ASD formulation have been assessed to ensure human safety before clinical trials could be initiated.Methods & findingsSafety pharmacology, toxicity and genotoxicity studies have been conducted with the flubendazole ASD formulation.In animals, flubendazole has good oral bioavailability from an ASD formulation ranging from 15% in dogs, 27% in rats to more than 100% in jirds. In in vivo toxicity studies with the ASD formulation, high systemic exposure to flubendazole and its main metabolites was reached. Flubendazole, up to high peak plasma concentrations, does not induce Cmax related effects in CNS or cardiovascular system. In repeated dose toxicity studies in rats and dogs, flubendazole-induced changes were observed in haematological, lymphoid and gastrointestinal systems and in testes. In dogs, the liver was an additional target organ. Upon treatment cessation, at least partial recovery was observed for these changes in dogs. In rats, the No Observed Adverse Effect Level (NOAEL) was 5 mg (as base)/kg body weight/day (mg eq./kg/day) in males and 2.5 mg eq./kg/day in females. In dogs, the NOAEL was lower than 20 mg eq./kg/day. Regarding genotoxicity, flubendazole was negative in the Ames test, but positive in the in vivo micronucleus test.ConclusionsBased on these results, in combination with previously described genotoxicity and reproductive toxicity data and the outcome of the preclinical efficacy studies, it was concluded that no flubendazole treatment regimen can be selected that would provide efficacy in humans at safe exposure.

Infant growth faltering linked to subclinical mastitis, maternal faecal-oral contamination, and breastfeeding.

Infant growth faltering occurs in breastfed infants <6months of age. The possibility that maternal health status contributes to this growth faltering is underexplored. We investigated whether (a) subclinical mastitis (SCM), an asymptomatic inflammation of the breast, (b) maternal intestinal nematode and protozoan infections, indicators of faecal-oral contamination, or (c) poor breastfeeding practices increased the odds of stunting (length-for-age z-score<-2SD), underweight (weight-for-age z-score<-2SD), or low head circumference (head circumference-for-age z-score<-2SD) in breastfed infants in rural indigenous communities in Guatemala. Mother-infant dyads (n=105) were subdivided into those with and without SCM (milk Na:K ratio>0.6). Maternal and infant anthropometry were measured at the time of breast milk collection. Maternal stool samples were examined for the presence of intestinal nematodes and protozoa. Questionnaires were used to characterize breastfeeding practices (exclusivity and frequency) and support, hygiene (latrine use and household faucet), and infant diarrhoea. SCM occurred in 14% of women and was associated with increased odds of infant stunting (odds ratio [OR]=4.3; confidence interval [CI] [1.1, 15.8]), underweight (OR=9.2; CI [1.8, 48.0]), and low head circumference (OR=15.9; CI [2.6, 96.9]). Maternal pathogenic protozoa and nematodes were uncommon (<4%), but nonpathogenic protozoa were common (e.g., Entamoeba coli [39%]). Entamoeba coli increased the likelihood (OR=3.3; CI [1.02, 10.6]) of low head circumference, whereas higher breastfeeding frequency lowered its odds (OR=0.74, CI [0.56, 0.97]). Prevention of SCM may improve early infant growth, but public health measures that increase breastfeeding frequency and reduce faecal-oral contamination may be required to minimize low head circumference.

IDENTIFIKASI TELUR CACING NEMATODA USUS PADA KUKU MURID SEKOLAH DASAR NEGERI 11 RANOMEETO

Background: Humans are intestinal nematode hosts whose transmission occurs through soil or soil transmited helminthes, as a place of life and development of worm eggs and larvae before they are transmitted to the human body, especially in children who are used to playing or direct contact with the soil, allowing the nails of Nematode eggs to be exposed the intestine.Purpose: The aim of this study was to determine the presence of intestinal nematode worm eggs on Ranomeeto 11 elementary school students. Methode: The type of research used is descriptive research, which was conducted on 28 June - 2 July 2016. The sample in this study was taken by Simple Random Sampling. The data taken in the form of primary and secondary data with the research instrument is a checklist and examination results. Data analysis techniques and data presentation are descriptive and presented in the form of frequency distribution tables and narrated.Result: The results of research conducted on 37 nail samples of Ranomeeto 11 Elementary School students showed that there were 5 positive samples containing intestinal Nematode eggs which were 4 positive Ascaris lumbricoides (10.82%) and 1 positive Trichuris trichiura (2.70%) and 32 (86 , 48%) negative samples do not contain intestinal nematodes.Conclusion: The conclusion of this study is that there are 5 positive samples of intestinal Nematode worm eggs 13.51% and 32 negative samples 86.48% do not contain intestinal nematode worm eggs.

Unusual form of strongyloidiasis with gastric involvements: A case report

Rationale: Strongyloides stercoralis (S. stercoralis) is an intestinal nematode with a complicated life cycle that can involve the gastrointestinal system. Infected patients are generally asymptomatic; but if symptomatic, the symptoms will include skin rash, respiratory and gastrointestinal symptoms like abdominal pain, diarrhea, nausea and vomiting. Patient concerns: A 77-year old man presented with edema of the lower extremities and insignificant tenderness in the epigastric region. Diagnosis: The histopathology of gastric tissue showed severe inflammation and multiple ulcers in the cardia, antrum and proximal duodenum. A large number of rhabditiform larvae of S. stercoralis along with tissue hyperemia and infiltration of lymphoplasma cells, eosinophils, and neutrophils were found. Intervention: Treatment with albendazole. Outcome: Despite the albendazole treatment, the patient’s condition deteriorated and eventually died because of a sepsis-like syndrome. Lesson: Physicians should remain alert to the urgency due to threadworm, especially among the elderly people and immunosuppressed cases; and should ensure accurate diagnosis, suitable treatment and careful follow-up of these cases.

Strongyloides stercoralis infection in imported and local dogs in Switzerland: from clinics to molecular genetics.

Strongyloides stercoralis is a worldwide-distributed intestinal nematode affecting mainly humans and dogs. Canine strongyloidosis is generally characterised by diarrhoea, malabsorption and bronchopneumonia, and may be fatal in cases of impaired immunity. In recent years, molecular and epidemiological studies suggested that host-adapted populations of S. stercoralis with different zoonotic potential may exist. Clinical and subclinical cases of S. stercoralis infection have been increasingly diagnosed in imported (France, Belgium, Bulgaria) and locally born dogs in Switzerland, showing that this parasite is currently circulating in Europe. Three of these clinical cases will be described here. All three dogs presented severe disease, characterised by harsh diarrhoea, dehydration, vomiting, respiratory and/or neurologic signs, and needed intensive care and hospitalisation. One of these dogs was related to a Swiss breeding kennel, in which the infection was subsequently diagnosed in several other dogs. Faeces were analysed by three coproscopical methods including (i) the Baermann technique, which consistently identified the typical S. stercoralis first-stage larvae in both clinical and subclinical infections, (ii) the sedimentation-zinc chloride flotation and (iii) sodium acetate-acetic acid-formalin concentration (SAFC) methods, which allowed the additional identification of parasitic females and/or eggs in two of the clinical cases. Interestingly, S. stercoralis isolated from all three independent clinical cases exhibited an identical genetic background on the nuclear 18S rDNA (fragment involving hypervariable regions I and IV) and the mitochondrial cytochrome oxidase subunit I (cox1) loci, similar to that of zoonotic isolates from other geographical regions, and not to that of dog-adapted variants. Due to the clinical relevance and zoonotic potential of this parasite, the awareness of both diagnosticians and clinicians is strongly required.

Characterization of starch and gum arabic-maltodextrin microparticles encapsulating acacia tannin extract and evaluation of their potential use in ruminant nutrition.

ObjectiveThe use of tannin extract and other phytochemicals as dietary additives in ruminants is becoming more popular due to their wide biological actions such as in methane mitigation, bypass of dietary protein, intestinal nematode control, among other uses. Unfortunately, some have strong astringency, low stability and bioavailability, and negatively affecting dry matter intake and digestibility. To circumvent these drawbacks, an effective delivery system may offer a promising approach to administer these extracts to the site where they are required. The objectives of this study were to encapsulate acacia tannin extract (ATE) with native starch and maltodextrin-gum arabic and to test the effect of encapsulation parameters on encapsulation efficiency, yield and morphology of the microparticles obtained as well as the effect on rumen in vitro gas production.MethodsThe ATE was encapsulated with the wall materials, and the morphological features of freeze-dried microparticles were evaluated by scanning electron microscopy. The in vitro release pattern of microparticles in acetate buffer, simulating the rumen, and its effect on in vitro gas production was evaluated.ResultsThe morphological features revealed that maltodextrin/gum-arabic microparticles were irregular shaped, glossy and smaller, compared with those encapsulated with native starch, which were bigger, and more homogenous. Maltodextrin-gum arabic could be used up to 30% loading concentration compared with starch, which could not hold the core material beyond 15% loading capacity. Encapsulation efficiency ranged from 27.7%±6.4% to 48.8%±5.5% in starch and 56.1%±4.9% to 64.8%±2.8% in maltodextrin-gum arabic microparticles. Only a slight reduction in methane emission was recorded in encapsulated microparticles when compared with the samples containing only wall materials.ConclusionBoth encapsulated products exhibited the burst release pattern under the pH conditions and methane reduction associated with tannin was marginal. This is attributable to small loading percentages and therefore, other wall materials or encapsulation methods should be investigated.

1135. Strongyloides Stercolaris Serology in Transplant Patients: To Test or Not?

Background Strongyloides stercoralis is an intestinal nematode endemic to the tropics, subtropics, and to a limited extent the United States and Europe. The global estimates of strongyloidiasis are reported to range from 3 to 100 million infected worldwide; however, the true US prevalence is unclear. The seroprevalence of infection in solid-organ transplant candidates and recipients in the New Orleans, Louisiana region is also unknown. The purpose of this study was to identify the prevalence of Strongyloides seropositivity within transplant candidates at Ochsner Medical Center (OMC).MethodsPatients were identified using EPIC-CLARITY with ICD-9 and ICD-10 codes for any solid-organ transplant at OMC from July 2012 to December 2016. Inclusion criteria were age 18 or older, patients evaluated for solid-organ transplant, and Strongyloides IgG testing. Patients were excluded if they had other immunocompromising conditions or exposures including but not limited to steroids, TNF-alpha, or biologic agent use. The primary outcome was the overall prevalence rate of strongyloidiasis at OMC. Secondary outcome was the comparison of prevalence between January 1, 2012 to July 31, 2016 (when testing was ordered based on risk stratification) vs. August 1, 2016 to December 31, 2016 (when routine testing was implemented).ResultsWe analyzed a total of 1,047 patients which had 1,128 tests ordered for Strongyloides. Of those, 985 were unique patients (62 patients had multiple serological tests resulting in 81 repeat tests). During July 1, 2012 to July 31, 2016 testing yielded a total of 822 tests. From August 1, 2016 to December 31, 2016 testing yielded 306 tests.Overall, 43/1,128 (3.8%) tests were positive for Strongyloides. The remaining 1,085/1,128 (96.2%) tested negative. For our secondary outcome, we found that testing based on risk stratification yielded 22/822 (2.7%) positives while testing for all patients we had 21/306 (6.9%) positives.ConclusionOur data suggest that testing based on risk stratification yielded a lower prevalence rate as compared with generalized testing, underestimating the true incidence of disease (2.7% vs. 6.9%). Testing all patients being evaluated for transplantation will capture a greater number of patients with positive serology.Disclosures J. Garcia-Diaz, Astellas Pharma: Speaker’s Bureau, Speaker honorarium.

Relationship between Sanitation of Warung Makan Tegal and Intestinal Nematodes Infestations in Cockroaches in Tembalang District, Semarang City

Background: Cockroaches are insects that are considered disgusting and act as mechanical vectors. The existence of cockroaches in a place becomes a benchmark of low sanitation in the place. The properties possessed by cockroaches by eating anything, so that in looking for food can spread nematodes by walking and removing dirt on top of food, dishes or other eating utensils that pass. The purpose of this study was to determine the intestinal nematode infestation in cockroaches.Methods: This study was an observational study with a cross sectional approach. The stall samples were taken using a total sampling of 43 stalls and cockroach samples were determined by 2 cockroaches from each warteg.Results: Observations under a microscope showed that intestinal nematodes were found in cockroaches including hookworm (14.0%), and Oxyuris vermicularis (30.2%).Conclusion: Intestinal nematodes (hookworm and Oxyuris vermicularis) are found in cockroach bodies

Strongyloidiasis in Solid Organ Transplantation

Strongyloides stercoralis, an intestinal parasitic nematode (roundworm), infects more than 100 million people worldwide. While most infected immunocompetent persons are either asymptomatic or experience only mild, intermittent symptoms, immunosuppressed individuals, including those undergoing solid organ transplantation, are at increased risk for developing the frequently fatal hyperinfection syndrome. Donor-derived strongyloidiasis has recently become increasingly recognized and reported but current donor screening practices leave substantial room for improvement. Knowledge that available standard diagnostic tests have suboptimal performance characteristics has led to the development of newer diagnostic assays including use of polymerase chain reactions. Ivermectin has been considered the recommended therapeutic agent but current evidence suggests that it may be less effective than previously believed. Because of the increasing global performance of solid organ transplantation, together with the global presence of the parasite, this infection is of universal interest. While some management issues are yet to be resolved, fatal outcomes from Strongyloides hyperinfection syndrome can be prevented by appropriate pre-transplantation screening and treatment of the solid organ donor and/or the recipient.

Host- and Helminth-Derived Endocannabinoids That Have Effects on Host Immunity Are Generated during Infection.

Helminths have coevolved with their hosts, resulting in the development of specialized host immune mechanisms and parasite-specific regulatory products. Identification of new pathways that regulate helminth infection could provide a better understanding of host-helminth interaction and may identify new therapeutic targets for helminth infection. Here we identify the endocannabinoid system as a new mechanism that influences host immunity to helminths. Endocannabinoids are lipid-derived signaling molecules that control important physiologic processes, such as feeding behavior and metabolism. Following murine infection with Nippostrongylus brasiliensis, an intestinal nematode with a life cycle similar to that of hookworms, we observed increased levels of endocannabinoids (2-arachidonoylglycerol [2-AG] or anandamide [AEA]) and the endocannabinoid-like molecule oleoylethanolamine (OEA) in infected lung and intestine. To investigate endocannabinoid function in helminth infection, we employed pharmacological inhibitors of cannabinoid subtype receptors 1 and 2 (CB1R and CB2R). Compared to findings for vehicle-treated mice, inhibition of CB1R but not CB2R resulted in increased N. brasiliensis worm burden and egg output, associated with significantly decreased expression of the T helper type 2 cytokine interleukin 5 (IL-5) in intestinal tissue and splenocyte cultures. Strikingly, bioinformatic analysis of genomic and transcriptome sequencing (RNA-seq) data sets identified putative genes encoding endocannabinoid biosynthetic and degradative enzymes in many parasitic nematodes. To test the novel hypothesis that helminth parasites produce their own endocannabinoids, we measured endocannabinoid levels in N. brasiliensis by mass spectrometry and quantitative PCR and found that N. brasiliensis parasites produced endocannabinoids, especially at the infectious larval stage. To our knowledge, this is the first report of helminth- and host-derived endocannabinoids that promote host immune responses and reduce parasite burden.

Risk factors and prevalence of toxocariasis in pregnant women and diabetic patients compared to healthy adults in Ilam province, western Iran.

Toxocara is one of the common intestinal nematodes in dogs and cats and is the agent of tissue migratory larvae in humans. Customarily, the prevalence of human toxocariasis hovers around 15.8 % in Iran. Furthermore, other research outcomes demonstrated a tendency for an outbreak of toxocariasis in Iran. Therefore, we carried out a cross-sectional study and assessed the seroprevalence of toxocariasis humans in Ilam Province, western of Iran. A total of 539 serum samples were collected between September 2017 and March 2018 from patients referred to the Health Centers of Ilam province, Iran. Serum samples were investigated for the presence of Toxocara using IgG antibodies, ELISA (Enzyme-Linked Immunosorbent Assay) kit. Risk factors such as contact with cats and dogs, living in rural areas were investigated among the study population. Out of 539 total samples collected, 97 cases (17.99 %) were positive for anti-toxocara IgG antibodies. These antibodies were recovered from serum samples of otherwise healthy adults (15.54 %, 49/296), pregnant women (21.16 %, 40/189) and diabetic patients (14.81 %, 8/54). This study showed significant relationship between toxocariasis and contact with animal pets in all studied groups (P value ≤ 0.05) and a significant relationship between toxocariasis and living in rural areas among pregnant women (P value ≤ 0.05).