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Gastrointestinal nematode (GIN) infections are ubiquitous and often cause morbidity and reduced performance in livestock. Emerging anthelmintic resistance and increasing change in climate patterns require evaluation of alternatives to traditional treatment and management practices. Mathematical models of parasite transmission between hosts and the environment have contributed towards the design of appropriate control strategies in ruminants, but have yet to account for relationships between climate, infection pressure, immunity, resources, and growth. Here, we develop a new epidemiological model of GIN transmission in a herd of grazing cattle, including host tolerance (body weight and feed intake), parasite burden and acquisition of immunity, together with weather-dependent development of parasite free-living stages, and the influence of grass availability on parasite transmission. Dynamic host, parasite and environmental factors drive a variable rate of transmission. Using literature sources, the model was parametrised for Ostertagia ostertagi, the prevailing pathogenic GIN in grazing cattle populations in temperate climates. Model outputs were validated on published empirical studies from first season grazing cattle in northern Europe. These results show satisfactory qualitative and quantitative performance of the model; they also indicate the model may approximate the dynamics of grazing systems under co-infection by O. ostertagi and Cooperia oncophora, a second GIN species common in cattle. In addition, model behaviour was explored under illustrative anthelmintic treatment strategies, considering impacts on parasitological and performance variables. The model has potential for extension to explore altered infection dynamics as a result of management and climate change, and to optimise treatment strategies accordingly. As the first known mechanistic model to combine parasitic and free-living stages of GIN with host feed-intake and growth, it is well suited to predict complex system responses under non-stationary conditions. We discuss the implications, limitations and extensions of the model, and its potential to assist in the development of sustainable parasite control strategies.

The identification of gastrointestinal helminth infections of humans and livestock almost exclusively relies on the detection of eggs or larvae in faeces, followed by manual counting and morphological char-acterisation to differentiate species using microscopy-based techniques. However, molecular approaches based on the detection and quantification of parasite DNA are becoming more prevalent, increasing the sensitivity, specificity and throughput of diagnostic assays. High-throughput sequencing, from single PCR targets through to the analysis of whole genomes, offers significant promise towards providing information-rich data that may add value beyond traditional and conventional molecular approaches; however, thus far, its utility has not been fully explored to detect helminths in faecal samples. In this study, low-depth whole genome sequencing, i.e. genome skimming, has been applied to detect and char-acterise helminth diversity in a set of helminth-infected human and livestock faecal material. The strengths and limitations of this approach are evaluated using three methods to characterise and differ-entiate metagenomic sequencing data based on (i) mapping to whole mitochondrial genomes, (ii) whole genome assemblies, and (iii) a comprehensive internal transcribed spacer 2 (ITS2) database, together with validation using quantitative PCR (qPCR). Our analyses suggest that genome skimming can success-fully identify most single and multi-species infections reported by qPCR and can provide sufficient cov-erage within some samples to resolve consensus mitochondrial genomes, thus facilitating phylogenetic analyses of selected genera, e.g. Ascaris spp. Key to this approach is both the availability and integrity of helminth reference genomes, some of which are currently contaminated with bacterial and host sequences. The success of genome skimming of faecal DNA is dependent on the availability of vouchered sequences of helminths spanning both taxonomic and geographic diversity, together with methods to detect or amplify minute quantities of parasite nucleic acids in mixed samples.(c) 2023 The Author(s). Published by Elsevier Ltd on behalf of Australian Society for Parasitology. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Pianosa is a 10 km(2) Italian island in the Tyrrhenian Sea which is part of the Tuscan Archipelago National Park. In this island lives a brown hare population which, according to the literature, belongs to the ancestral taxon Lepus europaeus meridei that offers a unique opportunity to observe how the parasite biocoenosis shapes in condition of isolation, limited space availability and high population density. The aim of this work is to describe the helminth component community of a non-managed, isolated, and dense hare population, evaluating host-parasite relationship and parasite community structure. All 26 analyzed hares (13 males and 13 females) were in good physical conditions, and all of them harboured exclusively the nematode Protostrongylus oryctolagi only. This is the first report of this lungworm species in Italy. The estimated overall abundance was 48.15 worms per examined hare (range 3-258, median 50) and the parasites were unevenly distributed across host population, with few hosts having most parasites (aggregated or overdispersed distribution). No significant relationship was detected between the number of isolated parasites and hare sex and weigh. The effect of the isolation of Pianosa's hare population seems to have acted reducing parasite richness, while the high host density is probably the cause of the high prevalence and abundance of the single helminth species collected. In conclusion, despite the low impact of parasites confirmed also by the overdispersed parasite distribution, the low diversity of the studied parasite community sounds a warning for the management of the hare population and the whole Pianosa's ecosystem.

Helminths have co-evolved alongside their hosts for millions of years and haveadapted eloquent mechanisms that allow them to reside in the host withoutcausing significant pathology, or elimination. The ability of these parasites tomanipulate their specialised host is reflected by their continued persistence asa global health concern, with ~1 billion people infected with soil transmittedhelminths (STHs). Helminth infections have long been associated with reducedallergic and autoimmune diseases leading to the hypothesis that helminthsuppress the host immune system, and this has been confirmed in both animalmodels and controlled human infection studies. Many studies have shown thatmany suppressive effects of infection on the host immune system can beattributed to helminth excreted/secreted products (ES). A small but growing listof individual molecules from helminth ES have been characterised, and themechanism of action elucidated. For example, multiple helminth species havebeen identified to secrete TGFβ mimic proteins that can bind host TGFβreceptor and induce T-regulatory (Treg) immunosuppressive cells. However,the full repertoire of helminth secreted molecules that modulate the host ishypothesised to be far from complete. Our lab discovered the presence of extracellular vesicles (EVs) within ES fromthe mouse infective helminth Heligmosomoides polygyrus bakeri (H. bakeri).EVs are lipid bilayer enclosed nanoparticles that carry proteins, lipids andnucleic acids and are released ubiquitously by all cells and organisms studiedto date. In mammalian systems EVs provide a mechanism of communicationbetween near or distal cells. In the context of host-pathogen dynamics it isproposed that EVs could play a role in enabling parasites to condition theirenvironment during infection. There is mounting evidence of host-parasite EVmediated modulation occurrence between plants and colonising fungal cells,bacteria and mammalian host cells, and several parasites and theirmammalian hosts including several helminth species. During H. bakeri infection host immune suppression is thought to primarilyoccur during the adult stage of infection when the parasite resides in the lumenof the duodenum in close proximity to the intestinal epithelium. The intestinalepithelium plays an integral role both in helminth detection, and in mediatingparasite clearance. Therefore, I hypothesised that adult H. bakeri EVs targetthe intestinal epithelium and directly modulate this tissue. The goal of thisthesis was to determine the role of helminth EVs in infection dynamics andhost modulation in the intestinal epithelium. I aimed to address whether H.bakeri EVs enter the intestinal epithelium, whether uptake is targeted to aspecific cell type and how these effects the function of this tissue usingintestinal organoid models. To address these aims development and refinement of methods for high purityEV preparations and EV labelling was required in order to directly implicate H.bakeri EVs as the causative agent in host responses. In Chapter 3, I comparedvarious combinational approaches to EV isolation and improved the purity ofour EV and EV depleted HES preparations. I then assessed EV preparationsusing cryoEM which furthered our understanding of the morphology anddiversity of H bakeri secreted EVs. I trialled multiple labelling methodologiesand found a low-background labelling method that allowed high confidenceidentification of uptake for subsequent chapters. However, I later discoveredthat the majority of labelling techniques trialled had variable labelling efficiencywith low proportions of EVs labelled; this is a caveat to consider wheninterpreting results using labelled EVs. To understand how H. bakeri EVs interact with the intestinal epithelium Ideveloped methods to grow small intestinal 2-D organoids (enteroids) whichare in vitro cultures that reconstitute the intestinal epithelium (Chapter 4). 2-Denteroids have greater cellular complexity as compared to a homogenous cellline and allow us to address the question of cell type specificity for uptake. 2-D enteroid cultures maintained cellular polarisation and differentiated into 6-7major cell types of the intestinal epithelium. In Chapter 5, I demonstrated by using fluorescently labelled EVs that H. bakeriEVs enter organoid cells, however at a lower proportion than I see side-by-side for our cell line cultures. This led to the hypothesis that H. bakeri EVscould target specific cellular populations within the intestinal epithelium. Toidentify whether uptake of H. bakeri EVs occurs in a targeted fashion byspecific cell types I performed microscopy experiments aiming to co-localiseEVs with certain cell types. Microscopy approaches did not provide a definitiveanswer to the question of whether uptake is cell type specific. Next, I modifiedthe cellular proportion of our 2-D enteroids to identify whether this altered theproportion of EV uptake. Goblet and tuft cells are specialised cells of theepithelium that are strongly induced during helminth infection and mediatehelminth clearance; I reasoned that H. bakeri EVs may specifically enter andmodulate these cell types. Organoid cultures that were enriched in goblet andtuft cells showed no enhanced ability to take up EVs, suggesting that neithergoblet nor tuft cells are specifically targeted over other cell types; however, thisdata does not rule out that H. bakeri EVs can enter these cell types andmodulate them. Whether cell type specificity exists for the uptake of H. bakeriEVs within the intestinal epithelium remains unclear and is still an active areaof investigation. To understand how EV treatment of 2-D enteroids altered host geneexpression in Chapter 6, I performed RNA sequencing (RNA seq) andcharacterised the transcriptional changes within 2-D enteroids to H. bakeri EVsor EV depleted ES after 24 h. Genes critical for maintenance of stem cells, cellcycle and antimicrobial defence were downregulated by H. bakeri EVs. Withinthe intestinal epithelium only a proportion of the cells are mitotic, thereforechanges in cell cycle suggest a modulation of either stem cells of Transit-amplifying (TA) cells. I also identified several changes in cell type restricted genes expressed specifically by stem cells, Paneth cells, TA cells orEnteroendocrine cells (EECs). I now hypothesise EVs specifically modify thesecell types. To define the cell type specific responses after EV or EV depletedES treatment I performed single cell RNA seq, unfortunately the quality of ourcontrol sample made interpreting these results difficult. However, these dataserve as conformation of the cellular composition of our 2-D enteroids model. In addition, I also utilised our 2-D organoid model to perform novel co-culturedexperiments with live adult or larval stage 4 (L4) H. bakeri and performedtranscriptional analysis of the host epithelium under these conditions. Thesedata allow us to uncouple the impact of infection with whole parasites on theintestinal epithelium from any immune driven changes in the epithelium thatoccur in vivo. These data also serve as a comparison between host effectsattributed specifically to H. bakeri EVs, and changes induced by the wholeparasite. In summary, this thesis contributes new knowledge to our understanding of H.bakeri interactions with the intestinal epithelium in the absence of host immunedriven responses and distinguishes the role of secreted H. bakeri EVs inmodulating this tissue. I determined that H. bakeri EVs enter host epithelialcells in 2-D enteroids, but whether this is specifically targeted to certainsubpopulations remains elusive. I characterised the host gene expressionchanges upon H. bakeri EV treatment in 2-D enteroids, these findings furtherour understanding as a field of which host genes and pathways are targetedby H. bakeri. In the future, this thesis along with continued research, couldhave important implications for helminth eradication. Conversely, where H.bakeri EVs suppress specific genes or pathways involved in diseases of theintestinal epithelium such as ulcerative colitis, Crohn's disease, oradenocarcinoma, they could provide novel strategies for therapeutics.

Gastro-intestinal nematode (GIN) parasites play an important role in the ecological dynamics of many animal populations. Recent studies suggest fine-scale spatial variation in GIN infection dynamics are important in wildlife systems, but the environmental drivers underlying this variation remain poorly understood.We used data from over two decades of GIN parasite egg counts, host space use, and spatial vegetation data from a long-term study of Soay sheep on St Kilda to test how spatial autocorrelation and vegetation in an individual’s home range predict parasite burden across three age groups. We developed a novel approach to quantify the plant functional traits present in a home range to describe the quality of vegetation present.Effects of space and vegetation varied between age classes. In immature lambs, strongyle parasite faecal egg counts (FEC) were spatially structured, being highest in the north and south of our study area. Independent of host body weight and spatial autocorrelation, plant functional traits predicted parasite egg counts. Higher egg counts were associated with more digestible and preferred plant functional traits, suggesting the association could be driven by host density and habitat preference.In contrast, we found no evidence that parasite FEC were related to plant functional traits in the host home range in yearlings or adult sheep. Adult FEC were spatially structured, with highest burdens in the north-east of our study area, while yearling FEC showed no evidence of spatial structuring.Our findings support the importance of fine-scale environmental variation for wildlife disease ecology and provides new evidence that such effects may vary across demographic groups within a population. Parasite burdens in immature individuals appear more readily influenced by fine-scale spatial variation in the environment, highlighting the importance of such heterogeneity for our understanding of wildlife epidemiology and health.

The Russian Arctic supports wild sympatric ruminants and their data-deficient helminths. In this study, we: (1) collected fecal samples of wild and semiwild reindeer (Rangifer tarandus), muskoxen (Ovibos moschatus), and snow sheep (Ovis nivicola) across Palearctic North territories: Arkhangelsk Oblast (including Novaya Zemlya archipelago), Karelia and Sakha Republics, Kola, Yamal, Taimyr, and Chukotka Peninsulas, Bering, Svalbard, and Wrangel Islands; (2) conducted a coprological survey (noninvasive life-time method preferable for protected animals) to obtain eggs and larvae of helminths inhabiting digestive, respiratory, nervous, and muscular systems; (3) identified helminths according to their morphology and DNA sequences; (4) estimated parasite load per host; (5) analyzed our findings. Varestrongylus eleguneniensis (in reindeer) was reported for the Palearctic for the first time, while Orthostrongylus sp. was reported both for R. tarandus and for the Palearctic for the first time. Capillarid-type eggs were reported for snow sheep for the first time. The question of the role of wild Arctic ruminants as vectors for rotifers was raised.

More than two-hundred-million people are infected with filariae worldwide. However, there is no vaccine available that confers long-lasting protection against filarial infections. Previous studies indicated that vaccination with irradiated infective L3 larvae reduces the worm load. This present study investigated whether the additional activation of cytosolic nucleic acid receptors as an adjuvant improves the efficacy of vaccination with irradiated L3 larvae of the rodent filaria Litomosoides sigmodontis with the aim of identifying novel vaccination strategies for filarial infections. Subcutaneous injection of irradiated L3 larvae in combination with poly(I:C) or 3pRNA resulted in neutrophil recruitment to the skin, accompanied by higher IP-10/CXCL10 and IFN-β RNA levels. To investigate the impact on parasite clearance, BALB/c mice received three subcutaneous injections in 2-week intervals with irradiated L3 larvae in combination with poly(I:C) or 3pRNA prior to the challenge infection. Vaccination with irradiated L3 larvae in combination with poly(I:C) or 3pRNA led to a markedly greater reduction in adult-worm counts by 73% and 57%, respectively, compared to the immunization with irradiated L3 larvae alone (45%). In conclusion, activation of nucleic acid-sensing immune receptors boosts the protective immune response against L. sigmodontis and nucleic acid-receptor agonists as vaccine adjuvants represent a promising novel strategy to improve the efficacy of vaccines against filariae and potentially other helminths.

The recent revolution in tissue-resident macrophage biology has resulted largely from murine studies performed in C57BL/6 mice. Here, using both C57BL/6 and BALB/c mice, we analyze immune cells in the pleural cavity. Unlike C57BL/6 mice, naive tissue-resident large-cavity macrophages (LCMs) of BALB/c mice failed to fully implement the tissue-residency program. Following infection with a pleural-dwelling nematode, these pre-existing differences were accentuated with LCM expansion occurring in C57BL/6, but not in BALB/c mice. While infection drove monocyte recruitment in both strains, only in C57BL/6 mice were monocytes able to efficiently integrate into the resident pool. Monocyte-to-macrophage conversion required both T cells and interleukin-4 receptor alpha (IL-4Rα) signaling. The transition to tissue residency altered macrophage function, and GATA6+ tissue-resident macrophages were required for host resistance to nematode infection. Therefore, during tissue nematode infection, T helper 2 (Th2) cells control the differentiation pathway of resident macrophages, which determines infection outcome.

Ethnic minority groups are often subjected to exclusion, social and healthcare marginalization, and poverty. There appears to be important linkages between ethnic minority groups, poor socioeconomic status, and a high prevalence of parasitic infection. Data regarding the prevalence and health effects of IPIs are necessary in the development and implementation of targeted prevention and control strategies to eradicate intestinal parasitic infection in the high-risk population. Thus, we investigated for the first time the intestinal parasitic infection status (IPIs), the socioeconomic status, and sanitary condition in the communities of Moken and Orang Laut, the ethnic minority peoples living on the coast of southwest Thailand. A total of 691 participants participated in the present study. The information concerning socioeconomic status and sanitary condition of the study population was obtained by personal interviews using a picture questionnaire. Stool samples were collected and examined for intestinal parasitic infection using direct wet smear and formalin-ethyl acetate concentration techniques. The results revealed that 62% of the study population were infected with one or more types of intestinal parasites. The highest prevalence of intestinal parasitic infections was found in the 11–20-year-old age range group. A statistically significant difference of IPIs among the three communities were observed (p < 0.0001). There was a statistical difference concerning 44 multiple infections of soil-transmitted helminths (STHs) (p < 0.001), whereas no statistically significant difference in multiple infections of protozoa was observed (p > 0.55). The results also displayed the significant difference in socioeconomic status and sanitary condition among the Moken living in Ranong and Phang Nga and the Orang Laut living in the Satun province (p < 0.001). Our study found no direct association between parasitic infection status and ethnic/geographic features; however, socioeconomic status is the key factor associated with prevalence of intestinal parasitic infection, with the observation that the higher prevalence of IPIs is due to a low socioeconomic status, consequently leading to poor hygiene and sanitation practices. The picture questionnaire played a major role in information gathering, especially from those of low or no education. Lastly, data pertaining to the species of the parasites and the mode of transmission assisted in the identification of group-specific vulnerabilities and shortcomings that can be utilized in education and corrected to reduce the prevalence of infection in the study areas.

Durrington Walls was a large Neolithic settlement in Britain dating around 2500 BCE, located very close to Stonehenge and likely to be the campsite where its builders lived during its main stage of construction. Nineteen coprolites recovered from a midden and associated pits at Durrington Walls were analysed for intestinal parasite eggs using digital light microscopy. Five (26%) contained helminth eggs, 1 with those of fish tapeworm (likely Dibothriocephalus dendriticus) and 4 with those of capillariid nematodes. Analyses of bile acid and sterol from these 5 coprolites show 1 to be of likely human origin and the other 4 to likely derive from dogs. The presence of fish tapeworm reveals that the Neolithic people who gathered to feast at Durrington Walls were at risk of infection from eating raw or undercooked freshwater fish. When the eggs of capillariids are found in the feces of humans or dogs it normally indicates that the internal organs (liver, lung or intestines) of animals with capillariasis have been eaten, and eggs passed through the gut without causing disease. Their presence in multiple coprolites provides new evidence that internal organs of animals were consumed. These novel findings improve our understanding of both parasitic infection and dietary habits associated with this key Neolithic ceremonial site.

Wastewater treatment is a widely used health protection measure that can be applied to control the transmission of wastewater-related infectious diseases to communities exposed to wastewater. This study determined the efficiency of three full-scale constructed wetlands (CWs) in removing pathogenic parasites and fecal coliform (FC) bacteria from wastewater. Wastewater samples were collected from three CW systems located in the Dar es Salaam and Iringa regions of Tanzania. The modified Bailenger and modified Ziehl-Neelsen stain techniques were used to detect and quantify parasites. The membrane filtration method was used to detect and quantify FC bacteria. Data were analysed using IBM SPSS version 20. Helminth (Ascaris lumbricoides, hookworm, and Taenia spp.) eggs were completely removed by two CW systems. In all the systems, the removal of protozoa ranged from 99.8% to 100%. The mean concentrations of FCs in effluents ranged from 5 to 6 log units/100 mL. Effluents of all CW systems met the recommended parasitological quality requirements of the World Health Organization for the safe reuse of wastewater. FC effluents concentrations did not meet the local discharge standards of the Tanzania Bureau of Standards. Therefore, improvement to the CWs’ design, operation, and maintenance are required for the efficient removal of bacteria. Keywords: helminth, protozoa, fecal coliform, wastewater treatment, constructed wetland

Background Schistosomiasis is a major neglected tropical disease that affects up to 250 million individuals worldwide. The diagnosis of human schistosomiasis is mainly based on the microscopic detection of the parasite’s eggs in the feces (i.e., for Schistosoma mansoni or Schistosoma japonicum) or urine (i.e., for Schistosoma haematobium) samples. However, these techniques have limited sensitivity, and microscopic expertise is waning outside endemic areas. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) has become the gold standard diagnostic method for the identification of bacteria and fungi in many microbiological laboratories. Preliminary studies have recently shown promising results for parasite identification using this method. The aims of this study were to develop and validate a species-specific database for adult Schistosoma identification, and to evaluate the effects of different storage solutions (ethanol and RNAlater) on spectra profiles. Methods Adult worms (males and females) of S. mansoni and S. japonicum were obtained from experimentally infected mice. Species identification was carried out morphologically and by cytochrome oxidase 1 gene sequencing. Reference protein spectra for the creation of an in-house MALDI-TOF MS database were generated, and the database evaluated using new samples. We employed unsupervised (principal component analysis) and supervised (support vector machine, k-nearest neighbor, Random Forest, and partial least squares discriminant analysis) machine learning algorithms for the identification and differentiation of the Schistosoma species. Results All the spectra were correctly identified by internal validation. For external validation, 58 new Schistosoma samples were analyzed, of which 100% (58/58) were correctly identified to genus level (log score values ≥ 1.7) and 81% (47/58) were reliably identified to species level (log score values ≥ 2). The spectra profiles showed some differences depending on the storage solution used. All the machine learning algorithms classified the samples correctly. Conclusions MALDI-TOF MS can reliably distinguish adult S. mansoni from S. japonicum. Graphical Abstract

The prevalence of intestinal parasitic infection remains high in developing countries, especially because of geographic and socio-demographic factors. This study aimed to evaluate intestinal parasitic infection, as well as its risk factors, among children aged 36–45 months in a rural area (North Kodi) and an urban area (Kupang) of East Nusa Tenggara, Indonesia. Anthropometry, socio-demographic factors and personal hygiene practices were assessed. A total of 214 children participated in the study, and 200 stool samples were collected for intestinal parasite examination. Approximately 30.5% (61/200) of the children were infected with one or more intestinal parasites (67.2%; 41/61 being mono-parasitic infections and 32.8%; 20/61 being poly-parasitic infections). A total of 85 intestinal parasites were detected, consisting of 35.3% (30/85) protozoa and 64.7% (55/85) helminths. The predominant protozoa were Giardia lamblia (43%; 13/30) and Blastocystis spp. (33.3%; 10/30), whereas the predominant helminths were Trichuris trichiura (50.9%; 28/55) and Ascaris lumbricoides (43.6%; 24/55). Moreover, intestinal parasitic infection was associated with rural area (OR 4.5; 95%CI 2.3–8.6); the absence of treatment with deworming drugs (OR 2.56; 95%CI 1.3–5.0); sanitation facilities without a septic tank (OR 4.3; 95%CI 2.1–8.5); unclean water as a source of drinking water (OR 4.67; 95%CI 2.4–9.4); no handwashing practice after defecation (OR 3.2; 95%CI 1.4–7.3); and stunted children (OR 4.4; 95%CI 2.3–8.3). In conclusion, poly-parasitic infections were common in this study. Poor personal hygiene practice and sanitation factors contributed to the high prevalence of intestinal parasitic infection in 36–45-month-old children in East Nusa Tenggara, Indonesia.

Background The influence of diet on immune function and resistance to enteric infection and disease is becomingever more established. Highly processed, refined diets can lead to inflammation and gut microbiome dysbiosis,whilst health-promoting dietary components such as phytonutrients and fermentable fibres are thought to promotea healthy microbiome and balanced mucosal immunity. Chicory (Cichorium intybus) is a leafy green vegetable rich infibres and bioactive compounds that may promote gut health.Results Unexpectedly, we here show that incorporation of chicory into semisynthetic AIN93G diets renders micesusceptible to infection with enteric helminths. Mice fed a high level of chicory leaves (10% dry matter) had a morediverse gut microbiota, but a diminished type-2 immune response to infection with the intestinal roundworm Heligmosomoidespolygyrus. Furthermore, the chicory-supplemented diet significantly increased burdens of the caecumdwellingwhipworm Trichuris muris, concomitant with a highly skewed type-1 immune environment in caecal tissue.The chicory-supplemented diet was rich in non-starch polysaccharides, particularly uronic acids (the monomericconstituents of pectin). In accordance, mice fed pectin-supplemented AIN93G diets had higher T. muris burdens andreduced IgE production and expression of genes involved in type-2 immunity. Importantly, treatment of pectin-fedmice with exogenous IL-25 restored type-2 responses and was sufficient to allow T. muris expulsion.Conclusions Collectively, our data suggest that increasing levels of fermentable, non-starch polysaccharides inrefined diets compromises immunity to helminth infection in mice. This diet-infection interaction may inform newstrategies for manipulating the gut environment to promote resistance to enteric parasites. Background: The influence of diet on immune function and resistance to enteric infection and disease is becoming ever more established. Highly processed, refined diets can lead to inflammation and gut microbiome dysbiosis, whilst health-promoting dietary components such as phytonutrients and fermentable fibres are thought to promote a healthy microbiome and balanced mucosal immunity. Chicory (Cichorium intybus) is a leafy green vegetable rich in fibres and bioactive compounds that may promote gut health. Results: Unexpectedly, we here show that incorporation of chicory into semisynthetic AIN93G diets renders mice susceptible to infection with enteric helminths. Mice fed a high level of chicory leaves (10% dry matter) had a more diverse gut microbiota, but a diminished type-2 immune response to infection with the intestinal roundworm Heligmosomoides polygyrus. Furthermore, the chicory-supplemented diet significantly increased burdens of the caecum-dwelling whipworm Trichuris muris, concomitant with a highly skewed type-1 immune environment in caecal tissue. The chicory-supplemented diet was rich in non-starch polysaccharides, particularly uronic acids (the monomeric constituents of pectin). In accordance, mice fed pectin-supplemented AIN93G diets had higher T. muris burdens and reduced IgE production and expression of genes involved in type-2 immunity. Importantly, treatment of pectin-fed mice with exogenous IL-25 restored type-2 responses and was sufficient to allow T. muris expulsion. Conclusions: Collectively, our data suggest that increasing levels of fermentable, non-starch polysaccharides in refined diets compromises immunity to helminth infection in mice. This diet-infection interaction may inform new strategies for manipulating the gut environment to promote resistance to enteric parasites.

Intestinal tuft cells have been shown to induce type 2 immune responses during viable parasite infections, but whether oral supplementation with a parasitic exudate is able to promote type 2 immune responses that have been shown to positively regulate obesogenic metabolic processes is yet unresolved. High-fat fed mice were gavaged with pseudocoelomic fluid (PCF) derived from the helminth Ascaris suum or saline thrice a week during weeks 5–9, followed by examination of intestinal tuft cell activity, immune, and metabolic parameters. Helminth PCF upregulated expression of distinct genes in small intestinal tuft cells, including genes involved in regulation of RUNX1 and organic cation transporters. Helminth PCF also enhanced levels of innate lymphoid cells in the ileum, and eosinophils in epididymal white adipose tissue (eWAT). Network analyses revealed two distinct immunometabolic cues affected by oral helminth PCF in high-fat fed mice: one coupling the small intestinal tuft cell responses to the fat-to-lean mass ratio and a second coupling eosinophils in eWAT to general regulation of body fat mass. Our findings point to specific mechanisms by which oral supplementation with helminth PCF may translate into systems-wide effects linking to reduced body and fat mass gain in mice during high-fat feeding. Intestinal tuft cells have been shown to induce type 2 immune responses during viable parasite infections, but whether oral supplementation with a parasitic exudate is able to promote type 2 immune responses that have been shown to positively regulate obesogenic metabolic processes is yet unresolved. High-fat fed mice were gavaged with pseudocoelomic fluid (PCF) derived from the helminth Ascaris suum or saline thrice a week during weeks 5–9, followed by examination of intestinal tuft cell activity, immune, and metabolic parameters. Helminth PCF upregulated expression of distinct genes in small intestinal tuft cells, including genes involved in regulation of RUNX1 and organic cation transporters. Helminth PCF also enhanced levels of innate lymphoid cells in the ileum, and eosinophils in epididymal white adipose tissue (eWAT). Network analyses revealed two distinct immunometabolic cues affected by oral helminth PCF in high-fat fed mice: one coupling the small intestinal tuft cell responses to the fat-to-lean mass ratio and a second coupling eosinophils in eWAT to general regulation of body fat mass. Our findings point to specific mechanisms by which oral supplementation with helminth PCF may translate into systems-wide effects linking to reduced body and fat mass gain in mice during high-fat feeding.

Currently, the incidence of helminthiasis among children is still gaining high indicators. The frequent spread of helminthiasis among children is often a sign of weak immunity, as well as frequent morbidity. The spread of helminthiasis among the child population is a problem for the field of medicine. According to the World Health Organization, helminthiasis is an annual disease-causing damage to the population. In addition, the importance of this disease in pediatric practice is its rapid prevalence as well as its significant impact on the child population. most often, helminthiasis is masked under other diseases since the child has an allergic reaction. Parasitic diseases are directly related to household infotainment and the behaviour of residents, sanitary and hygienic and natural conditions. The most common type of helminthiasis is enterobiasis. The mechanism of spread of this helminthiasis in most cases depends on the violation of sanitary and hygienic conditions, as well as on areas located in low epidemiological conditions. On the one hand, an indicator for assessing the incidence of enterobiasis at a high level indicates the incidence of helminthiasis in this population. According to the conclusions of our review, the problem indicates that it is worth reviewing the prevention of helminthiasis, В настоящее время частота встречаемости гельминтоза среди детей остается высокой. Частое распространение гельминтов среди детей часто является признаком слабого иммунитета, а также частой заболеваемости. Распространение гельминтозов среди детского населения является проблемой для сферы медицины. По данным Всемирной Организации здравоохранения ежегодно среди болезней наносящий ущерб населению является гельминтозы. Кроме того, важность этого заболевания в педиатрической практике является быстрая распространенность а также значительное влияние на детское население. Чаще всего гельминтоз маскируются под другими заболеваниями, так как у ребенка появляется аллергическая реакция. Паразитарные заболевания это напрямую связано с бытовым инфразвуком и поведением населения, санитарно-гигиеническими и природными условиями. Наиболее распространенной формой среди гельминтозов является энтеробиоз. Механизм распространения этого гельминтоза во многом зависит от нарушения санитарно-гигиенических условий, а также от районов, расположенных в эпидемиологически низких условиях. С одной стороны, высокий уровень энтеробиоза является индикатором оценки заболеваемости что свидетельствует о заболеваемости населения гельминтозом. По выводам нашего обзора проблема указывает на то, что стоит пересмотреть профилактику гельминтозов.

Anthelmintic resistance (AR) has thus far only rarely been reported for intestinal helminths of dogs and cats, in contrast to parasites of livestock and horses. We highlight possible reasons for this striking and important discrepancy, including ecological, biological and genetic factors and/or intervention regimens of key intestinal helminths concerning both host groups. In view of the current knowledge related to the genetics, mechanisms and principles of AR development, we point at issues which in our view contribute to a comparatively lower risk of AR development in intestinal helminths of dogs and cats. Finally, we specify research needs and provide recommendations by which, based on the available information about AR in ruminant and equine helminths, the development of AR in dog and cat helminths may best be documented, prevented or at least postponed., Graphical abstract Image 1, Highlights • Identifying causes of differences in anthelmintic resistance between livestock and dogs & cats. • Discussion of roles of AR mechanisms, genetics and husbandry in delayed AR evolution in dogs & cats. • Research needs for improved tools to monitor AR development in dogs & cats.

The antioxidant superoxide dismutase (SOD) catalyses the dismutation of superoxide, a dangerous oxygen free radical, into hydrogen peroxide and molecular oxygen. Superoxide generation during the oxidative burst of the innate immune system is considered a key component of the host defence against invading pathogens. We demonstrate the presence and differential expression of two SODs in Fasciola hepatica, a leaderless cytosolic (FhSOD1) and an extracellular (FhSOD3) form containing a secretory signal peptide, suggesting that the parasites exploit these enzymes in distinct ways to counteract reactive oxygen species (ROS) produced by cellular metabolism and immune defences. Both enzymes are highly expressed by the infective newly excysted juvenile (NEJ) stages and are found in abundance in their excretory–secretory products (ES), but only FhSOD1 is present in adult ES, suggesting that the antioxidants have different functions and pathways of secretion, and are under separate temporal expression control during the migration, growth, and development of the parasite. Functionally, the recombinant FhSOD1 and FhSOD3 exhibit similar activity against superoxide to their mammalian counterparts. Confocal immuno-localisation studies demonstrated the presence of FhSOD1 and FhSOD3 on the NEJ tegument and parenchyma, supporting our suggestion that these enzymes are secreted during host invasion to protect the parasites from the harmful oxidative bursts produced by the activated innate immune response. By producing superoxide enzymatically in vitro, we were able to demonstrate robust killing of F. hepatica NEJ within 24 h post-excystment, and that the lethal effect of ROS was nullified with the addition of SOD and catalase (the antioxidant enzyme responsible for the dismutation of hydrogen peroxide, a by-product of the SOD reaction). This study further elucidates the mechanism by which F. hepatica protects against ROS derived from cellular metabolism and how the parasite could mitigate damage caused by the host’s immune response to benefit its survival.

Refereed/Peer-reviewed Parasitic helminth infections, while a major cause of neglected tropical disease burden, negatively correlate with the incidence of immune-mediated inflammatory diseases such as inflammatory bowel diseases (IBD). To evade expulsion, helminths have developed sophisticated mechanisms to regulate their host’s immune responses. Controlled experimental human helminth infections have been assessed clinically for treating inflammatory conditions; however, such a radical therapeutic modality has challenges. An alternative approach is to harness the immunomodulatory properties within the worm’s excretory–secretory (ES) complement, its secretome. Here, we report a biologics discovery and validation pipeline to generate and screen in vivo a recombinant cell-free secretome library of helminth-derived immunomodulatory proteins. We successfully expressed 78 recombinant ES proteins from gastrointestinal hookworms and screened the crude in vitro translation reactions for anti-IBD properties in a mouse model of acute colitis. After statistical filtering and ranking, 20 proteins conferred significant protection against various parameters of colitis. Lead candidates from distinct protein families, including annexins, transthyretins, nematode-specific retinol-binding proteins, and SCP/TAPS were identified. Representative proteins were produced in mammalian cells and further validated, including ex vivo suppression of inflammatory cytokine secretion by T cells from IBD patient colon biopsies. Proteins identified herein offer promise as novel, safe, and mechanistically differentiated biologics for treating the globally increasing burden of inflammatory diseases.

Introduction: This paper provides an overview of the current immunologic research findings of lymphatic filarial worms, which affect millions of people worldwide. Objectives: This paper aims to discuss the immunologic features of lymphatic filarial worms. It also aims to highlight their potential anti-inflammatory actions and the use of anti-filarial drugs against COVID-19. Methods: A literature review was performed to obtain insights on the immunologic features of lymphatic filarial worms. Results: The CD4+ (Th2) response profile is the main defence against filarial worms. Modulation of human immune responses are primarily mediated by parasite-secreted peptides. Lymphatic filarial worms have anti-inflammatory potentials. Drug repurposing of diethylcarbamazepine, doxycycline, and ivermectin can be looked upon against COVID-19. Conclusion: Lymphatic filarial worms have several immunologic effects on host immune systems, which promote chronic infection and curtail anti-inflammatory responses. Insights in this paper can serve as a guide for the understanding of immunologic aspects of lymphatic filarial worms.

Background: Ascaris worm, as one of the commonest helminthic infections, constitutes a major public health challenge and concern in the majority of developing countries. This study was conducted to assess the prevalence of Ascaris worm infection and its associated risk factors among primary school children in Lambata community to determine the prevalence of Ascaris infection, age, gender and associated risk factors among them to create awareness and effective management program. Methods: This is a cross-sectional descriptive study conducted between January 2019 and November 2020, in nine selected primary schools in Lambata community. A total of 303 stool samples were collected using random sampling to determine the prevalence of Ascaris infection using stool smear technique. The socio-demographic data were collected, using a structured interview questionnaire. The collected data were analyzed using simple percentages, OR and chi-square analytical methods. Results: Out of the 303 screened stool samples, 156 (51.5%) had Ascaris infection. The most infected age-groups were 11-12 years old (73.8%; OR = 2.11) and 9-10 years (57.1%; OR = 2.01), while 6-8 year old subjects had the lowest rate (42.3%; OR = 1.00) of infection. Males (65.9%; OR= 2.00) were more infected than their female (39.9%; OR = 0.09) counterparts (P

The California kingsnake (Lampropeltis californiae), native to North America, is a significant threat to the conservation of endemic species in the Spanish Macaronesian island of Gran Canaria. However, its role disseminating potential invasive parasites, such as zoonotic pentastomids, has not been proven. Among its parasitic fauna, only protistans have been documented, in contrast to other Lampropeltis spp., which are known to carry pentastomids. Thus, a parasitological study is urgently required. Between 2016 and 2018, a total of 108 snakes were necropsied and stool samples examined. A single snake was infested with Ophionyssus natricis, and another individual with Serpentirhabdias sp. Only this latter snake presented gross lesions, characterized by granulomatous pneumonia. No Pentastomida were found. By contrast, almost the entire population (98.5%) was infested with larval helminths (three different nematode and two cestode species), characterized by granulomatous gastrointestinal serositis. This suggests the snake poses a ‘dead end’ host for local parasites. Based on these findings, snakes in Gran Canaria carry potential zoonotic mites, which along with Serpentirhabdias sp. could represent a threat to endemic lizards. The presence of metazoan parasites and their lesions are reported for the first time in the California kingsnake.

Parasites are strictly associated with their hosts and present a great diversity of life histories, often resulting in different diversity patterns than those observed in free-living species. However, ecological approaches have detected that, in some cases, mammal-associated helminths respond similarly to non-parasitic species in terms of diversity patterns. Using 2200 recorded interactions, we analysed the diversity patterns of helminths (Acanthocephala, Nematoda and Platyhelminthes) harbored by humans, wild and domestic mammals of Mexico, depending on latitude, host body mass and trophic guild (carnivore, herbivore, insectivore, omnivore), considering helminth richness and average taxonomic distinctness, and host phylogenetic diversity and phylogenetic clustering. Latitude was positively correlated with the average taxonomic distinctness encompassing the three parasite phyla and nematodes. Northern latitudes had less taxonomically related parasite assemblages. Host body mass had a significant negative relationship with the average taxonomic distinctness of acanthocephalans and the richness of helminths associated to wild hosts. The omnivore hosts had greater parasite richness, while insectivores had a less taxonomically related parasite assemblage and herbivores had a more heterogeneous parasite assemblage. Our results highlight the importance of incorporating different dimensions of diversity, such as average taxonomic distinctness and to consider the composition of parasite assemblages to better understand their diversity patterns., Graphical abstract Image 1, Highlights • Four diversity measures were used to describe diversity patterns of helminths. • Latitude was positively correlated with helminth average taxonomic distinctness. • Host body mass was negatively related with the helminth richness of wildlife hosts. • Helminth sets of omnivore hosts were richer in parasite species. • Helminth sets of insectivore hosts had a wider taxonomic breadth.

Guignas (Leopardus guigna) are small felids closely associated with native forest habitats. In fragmented landscapes, they use vegetation corridors and forest remnants to move across the landscape. In these contexts, guignas may increase contact probabilities with domestic animals, being therefore relevant to assess their pathogens and parasites. The aim of this study was to characterize the helminth fauna in the gastrointestinal tract and cardiorespiratory system of guignas from central and southern Chile. Between 2015 and 2018, 33 dead free-ranging guignas were found road-killed or were collected from wildlife rescue centers. Thirty-two gastrointestinal tracts and 32 cardiorespiratory organs were analyzed through direct analysis and artificial digestion. We found 81.8% (27/33) guignas were positive for helminth endoparasites (84.4% (27/32) positive for gastrointestinal parasites, 37.5% (12/32) positive for cardiorespiratory parasites). Fourteen parasites were identified (7 at genus level and 7 at species level), with Angiostrongylus sp., Molineus sp., Oslerus sp. and Troglostrongylus sp. as first records in guignas. The most prevalent parasites were the species Toxascaris leonina, Toxocara cati and Uncinaria stenocephala. Uncinaria stenocephala showed the highest intensity of infection. Multiparasitism was observed in 76% of the animals. Significant differences in richness of endoparasites and prevalence of cardiorespiratory parasites were found between geographic zones; higher values in the southern zone are possibly due to favorable environmental characteristics for endoparasite development. There were no statistically significant differences between sexes. All the parasites found in this study have been previously reported in domestic cats. These results are valuable to understand parasite transmission at the domestic-wildlife interface; the possibility of endoparasite transmission between domestic cats and guignas should be clarified with molecular analysis.

This study examined the prevalence and intensity of intestinal helminth infections and their association with anemia, undernutrition, and academic performance among school children in Maksegnit, northwestern Ethiopia. A total of 1205 school children, who attended Maksegnit Number Two Elementary School between May and July 2021, participated in this study. To determine helminth infection status, two thick Kato–Katz slides were examined for each child. Hemoglobin level was measured using a HemoCue machine. Academic performance was assessed using the mean score of all subjects children have taken for the Spring 2020/2021 academic term. Out of 1205 children examined, 45.4% were infected with at least one helminth species, 7.9% were anemic, and 35.8% were undernourished. The means for hemoglobin level and z-scores of weight for age, height for age, body mass index for age, and academic scores were lower among helminth-infected children than the uninfected. Children infected with intestinal helminths showed higher odds of anemia than those uninfected with helminths. In conclusion, there was a moderate prevalence of intestinal helminth infection and undernutrition among school children in Maksegnit. Intestinal helminth infection could increase the risk of anemia, undernutrition, and poor academic performance.

The liver fluke, Fasciola hepatica, is an obligate blood-feeder, and the gastrodermal cells of the parasite form the interface with the host’s blood. Despite their importance in the host–parasite interaction, in-depth proteomic analysis of the gastrodermal cells is lacking. Here, we used laser microdissection of F. hepatica tissue sections to generate unique and biologically exclusive tissue fractions of the gastrodermal cells and tegument for analysis by mass spectrometry. A total of 226 gastrodermal cell proteins were identified, with proteases that degrade haemoglobin being the most abundant. Other detected proteins included those such as proton pumps and anticoagulants which maintain a microenvironment that facilitates digestion. By comparing the gastrodermal cell proteome and the 102 proteins identified in the laser microdissected tegument with previously published tegument proteomic datasets, we showed that one-quarter of proteins (removed by freeze–thaw extraction) or one-third of proteins (removed by detergent extraction) previously identified as tegumental were instead derived from the gastrodermal cells. Comparative analysis of the laser microdissected gastrodermal cells, tegument, and F. hepatica secretome revealed that the gastrodermal cells are the principal source of secreted proteins, as well as showed that both the gastrodermal cells and the tegument are likely to release subpopulations of extracellular vesicles (EVs). Microscopical examination of the gut caeca from flukes fixed immediately after their removal from the host bile ducts showed that selected gastrodermal cells underwent a progressive thinning of the apical plasma membrane which ruptured to release secretory vesicles en masse into the gut lumen. Our findings suggest that gut-derived EVs are released via a novel atypical secretory route and highlight the importance of the gastrodermal cells in nutrient acquisition and possible immunomodulation by the parasite.

Helminths survive within their host by secreting immunomodulatory compounds, which hold therapeutic potential for inflammatory conditions. Helminth-derived extracellular vesicles (EVs) are one such component proposed to possess immunomodulatory activities. Due to the recent discovery of helminth EVs, standardised protocols for EV separation are lacking. Excretory/secretory products of the porcine helminth, Ascaris suum, were used to compare three EV separation methods: Size exclusion chromatography (SEC), ultracentrifugation (UC) and a combination of the two. Their performance was evaluated by EV yield, sample purity and the ability of EVs to suppress lipopolysaccharide (LPS)-induced inflammation in vitro. We found that all three separation methods successfully separated helminth EVs with a similar EV yield. Functional studies showed that EVs from all three methods reduced LPS-induced levels of tumour necrosis factor (TNF-α) in a dose-dependent manner. Overall, the three separation methods showed similar performance, however, the combination of UC+SEC presented with slightly higher purity than either method alone.

This study was conducted to determine the prevalence of gastrointestinal helminth and protozoan infections in 121 puppies aged 2-6 months in Konya. For this purpose, collected stool samples were examined by Fulleborn flotation and sedimentation methods. Helminth eggs, protozoan cysts, oocysts, and sporocysts detected in stool examinations were identified by related literatures. In total, 92 of 121 stool samples (76.03%) were found positive for helminth and protozoan infections. In stool samples, Giardia spp. cysts (2.48%), Sarcocystis spp. sporocysts (2.48%) and Isospora spp. oocysts (26.45%) were found as protozoan parasites. Cestode and nematode infections were found among gastrointestinal helminths, but no trematode infection was detected. Joyeuxiella spp. (1.65%), Dipylidium caninum (10.74%), Taenia/Echinococcus spp. (0.83%), Toxascaris leonina (33.06%), Toxacara canis (38.84%) and Physaloptera spp. (6.61%) eggs were detected as helminths in the study. The presence of single and mixed parasite infections was also detected in some dogs in the study. This study revealed 47.82% single, 43.48% dual, and 7.61% triple mixed infections. Four different parasites were found in a stool sample, including one protozoan cyst and three different helminth eggs (Isospora spp., T. leonina, T. cati, and D. caninum). This is the first study reporting Physaloptera spp. infection in dogs in Turkey., Bu çalışma Konya ilinde 2-6 aylık 121 adet yavru sokak köpeğinin gastro-intestinal helmint ve protozoon enfeksiyonlarının yaygınlığını belirlemek amacıyla yapılmıştır. Bu amaçla toplanan gaita örnekleri Fulleborn flotasyon ve sedimantasyon yöntemleri ile incelenmiştir. Mikroskobik muayenede tespit edilen helmint yumurtası ile protozoon kist, ookist ve sporokistleri ilgilili teratürler yardımıyla teşhis edilmiştir. Toplamda 121 adet gaita numunesinin 92’si (%76.03) helmint ve protozoon enfeksiyonları açısından pozitif bulunmuştur. Gaita örneklerinde protozon parazitlerden Giardia spp. kistleri (%2.48), Sarcocystis spp. sporokistleri (%2.48) ve Isospora spp. ookistlerine (%26.45) rastlanmıştır. Gastrointestinal helmintlerden ise cestod ve nematode enfeksiyonlarına rastlanmış, ancak herhangi bir trematod enfeksiyonu belirlenmemiştir. Çalışmada helmintlerden Joyeuxiella spp. (%1.65), Dipylidium caninum (%10.74), Taenia/Echinococcus spp. (%0.83), Toxascaris leonina (%33.06), Toxacara canis (%38.84) ve Physaloptera spp. (%6,61) yumurtalarının varlığı tespitedilmiştir. Bu çalışmada ayrıca bazı köpeklerde tekli ve miks parazit enfeksiyonlarının varlığı tespit edilmiştir. Çalışmada %47.82 tekli, %43.48 ikili ve %7.61 üçlü miks enfeksiyonlar tespit edilmiştir. Bir dışkı örneğinde ise biri protozoon kisti ve üçü de farklı helmint yumurtası olmak üzere (Isospora spp., T. leonina, T. cati ve D. caninum) dört farklı parasite rastlanmıştır. Bu çalışma Türkiye’de köpeklerde Physaloptera spp. enfeksiyonunun bildirildiği ilk çalışmadır.

Proanthocyanidins (PAC) are dietary polyphenols with putative anti-inflammatory and immunomodulatory effects. However, whether dietary PAC can regulate type-2 immune function and inflammation at mucosal surfaces remains unclear. Here, we investigated if diets supplemented with purified PAC modulated pulmonary and intestinal mucosal immune responses during infection with the helminth parasite Ascaris suum in pigs. A. suum infection induced a type-2 biased immune response in lung and intestinal tissues, characterized by pulmonary granulocytosis, increased Th2/Th1 T cell ratios in tracheal-bronchial lymph nodes, intestinal eosinophilia, and modulation of genes involved in mucosal barrier function and immunity. Whilst PAC had only minor effects on pulmonary immune responses, RNA-sequencing of intestinal tissues revealed that dietary PAC significantly enhanced transcriptional responses related to immune function and antioxidant responses in the gut of both naïve and A. suum-infected animals. A. suum infection and dietary PAC induced distinct changes in gut microbiota composition, primarily in the jejunum and colon, respectively. Notably, PAC consumption substantially increased the abundance of Limosilactobacillus reuteri. In vitro experiments with porcine macrophages and intestinal epithelial cells supported a role for both PAC polymers and PAC-derived microbial metabolites in regulating oxidative stress responses in host tissues. Thus, dietary PAC may have distinct beneficial effects on intestinal health during infection with mucosal pathogens, while having a limited activity to modulate naturally-induced type-2 pulmonary inflammation. Our results shed further light on the mechanisms underlying the health-promoting properties of PAC-rich foods, and may aid in the design of novel dietary supplements to regulate mucosal inflammatory responses in the gastrointestinal tract.

This study aims to determine the prevalence of helminthiasis and find various kinds of egg worms in cattle through feces examination in Magetan Regency. A hundred cattle feces samples were collected from six animal markets in Magetan Regency. The Faecal examination was performed by native, sediments, and Flotation methods. The results of this study showed that there were 40 samples positively infected by a helminth, which indicated that the prevalence of helminthiasis in cattle was 40%. The kind of helminth were Oesophagostomum sp. (14%), Bunostomum sp. (8%), Mecistocirrus sp. (8%), Haemonchus sp. (4%), Toxocara vitulorum (3%), Trichuris sp. (2%), Strongyloides sp. (2%), and Fasciola sp. (11%).

Gastrointestinal nematodes (GIN) pose a severe threat to sheep production worldwide. Anthelmintic drug resistance coupled with growing concern regarding potential environmental effects of drug use have demonstrated the necessity of implementing other methods of GIN control. The aim of this study was to test for genetic variants associated with resistance or susceptibility to GIN in Katahdin sheep to improve the current understanding of the genetic mechanisms responsible for host response to GIN. Linear regression and case-control genome-wide association studies were conducted with high-density genotype data and cube-root transformed weaning fecal egg counts (tFEC) of 583 Katahdin sheep. The case-control GWAS identified two significant SNPs (P-values 1.49e-08 to 1.01e-08) within introns of the gene adhesion G protein-coupled receptor B3 (ADGRB3) associated with lower fecal egg counts. With linear regression, four significant SNPs (P-values 7.82e-08 to 3.34e-08) were identified within the first intron of the gene EGF-like repeats and discoidin domains 3 (EDIL3). These identified SNPs were in very high linkage disequilibrium (r(2) of 0.996-1), and animals with alternate homozygous genotypes had significantly higher median weaning tFEC phenotypes compared to all other genotypes. Significant SNPs were queried through public databases to identify putative transcription factor binding site (TFBS) and potential lncRNA differences between reference and alternate alleles. Changes in TFBS were predicted at two SNPs, and one significant SNP was found to be within a predicted lncRNA sequence with greater than 90% similarity to a known lncRNA in the bovine genome. The gene EDIL3 has been described in other species for its roles in the inhibition and resolution of inflammation. Potential changes of EDIL3 expression mediated through lncRNA expression and/or transcription factor binding may impact the overall immune response and reduce the ability of Katahdin sheep to control GIN infection. This study lays the foundation for further research of EDIL3 and ADGRB3 towards understanding genetic mechanisms of susceptibility to GIN, and suggests these SNPs may contribute to genetic strategies for improving parasite resistance traits in sheep. Organic Agriculture Research and Extension Initiative grant [2016-51300-25723]; USDA National Institute of Food and AgricultureUnited States Department of Agriculture (USDA) [IDA01566] Published version This research was funded by the Organic Agriculture Research and Extension Initiative grant no. 2016-51300-25723 and Hatch grant IDA01566 from the USDA National Institute of Food and Agriculture.

Diabetes is recognised as the world's fastest growing chronic condition globally. Helminth infections have been shown to be associated with a lower prevalence of type 2 diabetes (T2D), in part due to their ability to induce a type 2 immune response. Therefore, to understand the molecular mechanisms that underlie the development of T2D-induced insulin resistance, we treated mice fed on normal or diabetes-promoting diets with excretory/secretory products (ES) from the gastrointestinal helminth Nippostrongylus brasiliensis. We demonstrated that treatment with crude ES products from adult worms (AES) or infective third-stage larvae (L3ES) from N. brasiliensis improved glucose tolerance and attenuated body weight gain in mice fed on a high glycaemic index diet. N. brasiliensis ES administration to mice was associated with a type 2 immune response measured by increased eosinophils and IL-5 in peripheral tissues but not IL-4, and with a decrease in the level of IL-6 in adipose tissue and corresponding increase in IL-6 levels in the liver. Moreover, treatment with AES or L3ES was associated with significant changes in the community composition of the gut microbiota at the phylum and order levels. These data highlight a role for N. brasiliensis ES in modulating the immune response associated with T2D, and suggest that N. brasiliensis ES contain molecules with therapeutic potential for treating metabolic syndrome and T2D. This research was supported by a program grant from the National Health and Medical Research Council (1132975), and a strategic research initiative award from the Australian Research Council to The Australian Institute of Tropical Health and Medicine at James Cook University (SRI40200003). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sí

Many helminth life cycles, including hookworm, involve a mandatory lung phase, where myeloid and granulocyte subsets interact with the helminth and respond to infection-induced lung injury. To evaluate these innate subsets, we employ Nippostrongylus brasiliensis infection of reporter mice for myeloid cells (CX3CR1(GFP)) and granulocytes (PGRP(dsRED)). Nippostrongylus infection induces lung infiltration of reporter cells, including CX3CR1(+) myeloid cells and PGRP(+) eosinophils. Strikingly, CX3CR1(GFP/GFP) mice, which are deficient in CX3CR1, are protected from Nippostrongylus infection with reduced weight loss, lung leukocyte infiltration, and worm burden compared to CX3CR1(+/+) mice. This protective effect is specific for CX3CR1 as CCR2-deficient mice do not exhibit reduced worm burdens. Nippostrongylus co-culture with lung Ly6C(+) monocytes or CD11c(+) cells demonstrates that CX3CR1(GFP/GFP) monocytes secrete more proinflammatory cytokines, and actively bind the parasites causing reduced motility. RNA sequencing of Ly6C(+) or CD11c(+) cells shows Nippostrongylus-induced gene expression changes, particularly in monocytes, associated with inflammation, chemotaxis, and extracellular matrix remodeling pathways. We also identify cytotoxic and adhesion molecules as potential effectors against the parasite, such as Gzma and Gzmb, which are elevated in CX3CR1(GFP/GFP) monocytes. These studies validate a dual innate cell reporter for lung helminth infection and demonstrate that CX3CR1 impairs monocyte-helminth interaction.

Background: Iron deficiency is a dominant source of anaemia in many settings. To evaluate the key cause of anaemia in the study area, the prevalence of anaemia due to major public health diseases was compared with anaemia due to iron deficiency. Methods: Pregnant women were recruited from ante-natal (n=490) and HIV clinics (n=217) with their personal data docu- mented using a questionnaire. Microscopy of Giemsa-stained thick smears was used for detection of malaria parasites while helminths in stools were detected using direct smear method. Haematocrit values were determined by capillary method. Se- rum ferritin levels were determined using enzyme-linked immunosorbent assay. Data was analysed using SPSS version 22.0. Results: The mean age of the recruited women was 28.6±5.4 years old. There were 68.1% cases of anaemia of which 35.5% was due to infections only predominantly HIV and malaria, 14.9% from unknown sources while anaemia due to iron deficiency only was 7.1%. Conclusion: It can safely be inferred that malaria and HIV predispose to anaemia than iron deficiency in the study area. Although pregnant women are dewormed and given IPTp for helminths and malaria treatment respectively, there should be complementary routine malaria screening at ANC visits for those with HCT values

Birhanu Ayelign,1 Yonas Akalu,2 Banchamlak Teferi,3 Meseret Derbew Molla,4 Tewodros Shibabaw4 1Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia; 2Department of Physiology, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia; 3Department of Clinical Pharmacy, School of Pharmacy, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia; 4Department of Biochemistry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, EthiopiaCorrespondence: Birhanu AyelignDepartment of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, EthiopiaEmail birhanuayelign42@gmail.comAbstract: Allergic diseases are increasing at an alarming rate worldwide, particularly in developed countries. In contrast, there is a decrease in the prevalence of helminthic infections and other neglected diseases. The hygiene hypothesis elaborates parasitic infection, and allergy-associated diseases have an inverse relationship. Acute helminthic infection and allergic reaction stimulate Type 2 helper cells (Th2) immune response with up-regulation of cytokines IL-4-, IL-5-, and IL-13-mediated IgE and mast cell production, as well as eosinophilia. However, people who chronically suffer from helminthic infections are demarcated through polarized Th2 resulting in alternative macrophage activation and T regulatory response. This regulatory system reduces allergy incidence in individuals that are chronically diseased through helminth. As a result, the excretory-secretory (ES) substance derived from parasites and extracellular vesicular components can be used as a novel therapeutic modality of allergy. Therefore, the aim of this review meticulously explored the link between helminth infection and allergy, and utilization of the helminth secretome for therapeutic immunomodulation.Keywords: allergy, helminth, IgE, Treg, hygiene hypothesis, immunotherapy

Graphical abstract, Highlights • Current vaccine candidates against helminth infection have shown limited success. • Helminths release extracellular vesicles (EVs) which act on host cells and are a rich source of antigens for new vaccines. • The biogenesis, release and immunomodulatory functions of helminth EVs are reviewed. • Utilisation of EVs in vaccine generation are discussed, including potential antigens and routes of delivery., The hunt for effective vaccines against the major helminth diseases of humans has yet to bear fruit despite much effort over several decades. No individual parasite antigen has proved to elicit full protective immunity, suggesting that combinatorial strategies may be required. Recently it has been discovered that extracellular vesicles released by parasitic helminths contain multiple potential immune modulators, which could together be targeted by a future vaccine. Increasing knowledge of helminth extracellular vesicle components, both enclosed by and exposed on the membrane, will open up a new field of targets for an effective vaccine. This review discusses the interactions between helminth extracellular vesicles and the immune system discovered thus far, and the advantages of targeting these lipid-bound packages with a vaccine. In addition, we also comment upon specific antigens that may be the best targets for an anti-helminth vaccine. In the future, extensive knowledge of the parasites' full arsenal in controlling their host may finally provide us with the ideal target for a fully effective vaccine.

Parasite burdens are known to vary seasonally in wildlife, and rainfall is one key aspect of seasonality that has been linked to parasitism in a range of systems. Rainfall can have immediate effects on parasitism rates by affecting parasite survival and movement in the environment, or it can have delayed effects by affecting host susceptibility to parasites through changes in host body condition or immune function. In this study, we examined how helminth infection in a wild ungulate (Grant's gazelle, Nanger granti) is impacted by seasonal changes in rainfall. We looked at how the burdens of three helminth parasites varied in relation to current (immediate effect) and prior (delayed effect) rainfall by comparing parasite fecal egg and larval counts to rainfall 0, 1, and 2 months prior to parasite sampling. We found burdens of all three parasites to be negatively associated with rainfall, and that delayed effects were stronger than immediate effects. Our findings implicate rainfall as a driver of seasonal variation in infection and suggest one important mechanism may be through delayed effects on host susceptibility., Graphical abstract Image 1, Highlights • Rainfall affects parasitism via delayed effects across three helminth taxa. • Rainfall is negatively associated with helminth parasite abundance and presence. • Host traits modify relationships between rainfall and parasitism.

Interactions between wildlife and livestock have increased over time with increased anthropogenic pressure on limited available natural habitats. These interactions have resulted in sharing of pathogens between the species resulting in impacting the wild animals’ fitness and reproduction and further influencing their abundance and diversity. The spatial overlap between Swamp Deer and livestock was studied at Jhilmil Jheel Conservation Reserve (JJCR), Uttarakhand and Kishanpur Wildlife Sanctuary (KWLS), Uttar Pradesh in India, having different levels of interaction with livestock. The prevalence, load and commonality of gastro-intestinal parasites in the species was studied through coprological examination. Parasitic ova of Strongyle sp., Trichostrongylus sp., Fasciola sp., and Moniezia sp. Amphistomes were encountered in swamp deer and livestock from both the sites. The parasitic species richness and prevalence however, varied between JJCR and KWLS. The study recorded significant differences between the parasitic load in Swamp Deer with the eggs per gram of 487.5±46.30 at JJCR and 363.64±49.97 at KWLS at varying levels of livestock interactions.

International audience; In the Mekong Delta region of Vietnam, small-scale chicken farming is common. However, high levels of disease or mortality in such flocks impair eco- nomic development and challenge the livelihoods of many rural households. We investigated 61 diseased small-scale flocks (122 chickens) for evidence of infec- tion with 5 bacteria, 4 viruses, and helminths. Sero- logical profiles (ELISA) were also determined against 6 of these pathogens. The aims of this study were the following: (1) to investigate the prevalence of different pathogens and to compare the probability of detection of bacterial pathogens using PCR and culture; (2) to investigate the relationship between detection of or- ganisms in birds’ tissues and the observed morbidity and mortality, as well as their antibody profile; and (3) to characterize risk factors for infection with specific viral or bacterial pathogens. We used PCR to test for viral (viruses causing infectious bronchitis [IB], highly pathogenic avian influenza [HPAI], Newcastle disease, and infectious bursal disease [IBD]) and bacterial pathogens (Mycoplasma gallisepticum, Pas- teurella multocida, Avibacterium paragallinarum, and Ornithobacterium rhinotracheale [ORT]). The latter two were also investigated in respiratory tissues by conventional culture. Colisepticemic Escherichia coli was investigated by liver or spleen culture. In 49 of 61 (80.3%) flocks, at least one bacterial or viral pathogen was detected, and in 29 (47.5%) flocks, more than one pathogen was detected. A. paragallinarum was detected in 62.3% flocks, followed by M. gallisepticum (26.2%), viruses causing IBD (24.6%) and IB (21.3%), septicemic E. coli (14.8%), ORT (13.1%), and HPAI viruses (4.9%). Of all flocks, 67.2% flocks were colonized by helminths. Mortality was highest among flocks infected with HPAI (100%, interquartile range [IQR]: 81.6– 100%) and lowest with flocks infected with ORT (5.3%, IQR: 1.1–9.0%). The results indicated slight agreement (kappa 0.167) between detection by PCR and culture for both A. paragallinarum and ORT, as well as be- tween the presence of cestodes and ORT infection (kappa 5 0.317). Control of A. paragallinarum, viruses causing HPAI, IBD, and IB, M. gallisepticum, and gastrointestinal helminths should be a priority in small- scale flocks.

The tapeworm Hymenolepis diminuta fails to establish in mice. Given the potential for helminth-bacteria interaction in the gut and the influence that commensal bacteria exert on host immunity, we tested if worm expulsion was related to alterations in the gut microbiota. Specific pathogen-free (SPF) mice, treated with broad-spectrum antibiotics, or germ-free wild-type mice were infected with H. diminuta, gut bacterial composition assessed by 16S rRNA gene sequencing, and worm counts, blood eosinophilia, goblet cells, splenic IL-4, -5 and -10, and colonic cytokines/chemokines mRNA were assessed. Effects of a PBS-soluble extract of adult H. diminuta on bacterial growth in vitro was tested. H. diminuta-infected mice displayed increased α and β diversity in colonic mucosa-associated and fecal bacterial communities, characterized by increased Lachnospiraceae and clostridium cluster XIVa. In vitro analysis revealed that the worm extract promoted the growth of anaerobic bacteria on M2GSC agar. H. diminuta-infection was accompanied by increased Th2 immune responses, and colon from infected mice had increased levels of IL-10, IL-25, Muc2, trefoil factor 3, and β2-defensin mRNA. SPF-mice treated with antibiotics, or germ-free mice, expelled H. diminuta with kinetics similar to control SPF mice. In both settings, measurements of Th2-immune responses were not significantly different across the groups. Thus, while infection with H. diminuta results in subtle but distinct changes to the colonic microbiota, we have no evidence to support an essential role for gut bacteria in the expulsion of the worm from the mouse host.

Background & Aims Epidemiological and animal studies have indicated an inverse correlation between the rising prevalence of obesity and metabolic syndrome and exposure to helminths. Whether helminth-induced immune response contributes to microbiota remodeling in obesity remains unknown. The aim of this study is to explore the immune-regulatory role of helminth in the prevention of HFD-induced obesity through remodeling gut microbiome. Methods C57BL/6J WT and STAT6-/- mice were infected with Heligmosomoides polygyrus and followed by high fat diet (HFD) feeding for 6 weeks. The host immune response, body weight, and fecal microbiota composition were analyzed. We used adoptive transfer of M2 macrophages and microbiota transplantation approaches to determine the impact of these factors on HFD-obesity. We also examined stool microbiota composition and short chain fatty acids (SCFAs) concentration and determined the expression of SCFA-relevant receptors in the recipient mice. Results Helminth infection of STAT6-/- (Th2-deficient) mice and adoptive transfer of helminth-induced alternatively activated (M2) macrophages demonstrated that the helminth-associated Th2 immune response plays an important role in the protection against obesity and induces changes in microbiota composition. Microbiota transplantation showed that helminth-induced, Th2-dependent alterations of the gut microbiota are sufficient to confer protection against obesity. Collectively, these results indicate that helminth infection protects against HFD-induced obesity by Th2-dependent, M2 macrophage-mediated alterations of the intestinal microbiota. Conclusion Our findings provide new mechanistic insights into the complex interplay between helminth infection, the immune system and the gut microbiota in a HFD-induced obesity model and holds promise for gut microbiome-targeted immunotherapy in obesity prevention., Graphical abstract

Neuropeptides comprise a diverse and broad group of neurotransmitters in vertebrates and invertebrates, with critical roles in neuronal signal transduction. While their role in controlling learning and memory in the brains of mammals is known, their extra-synaptic function in infection and inflammation with effects on distinct tissues and immune cells is increasingly recognized. Helminth infections especially of the central nervous system (CNS), such as neurocysticercosis, induce neuropeptide production by both host and helminth, but their role in host–parasite interplay or host inflammatory response is unclear. Here, we review the neurobiology of helminths, and discuss recent studies on neuropeptide synthesis and function in the helminth as well as the host CNS and immune system. Neuropeptides are summarized according to structure and function, and we discuss the complex enzyme processing for mature neuropeptides, focusing on helminth enzymes as potential targets for novel anthelminthics. We next describe known immunomodulatory effects of mammalian neuropeptides discovered from mouse infection models and draw functional parallels with helminth neuropeptides. Last, we discuss the anti-microbial properties of neuropeptides, and how they may be involved in host–microbiota changes in helminth infection. Overall, a better understanding of the biology of helminth neuropeptides, and whether they affect infection outcomes could provide diagnostic and therapeutic opportunities for helminth infections.

Filarial helminths infect approximately 120 million people worldwide initiating a type 2 immune response in the host. Influenza A viruses stimulate a virulent type 1 pro-inflammatory immune response that in some individuals can cause uncontrolled immunopathology and fatality. Although coinfection with filariasis and influenza is a common occurrence, the impact of filarial infection on respiratory viral infection is unknown. The aim of this study was to determine the impact of pre-existing filarial infection on concurrent infection with influenza A virus. A murine model of co-infection was established using the filarial helminth Litomosoides sigmodontis and the H1N1 (A/WSN/33) influenza A virus (IAV). Co-infection was performed at 3 different stages of L. sigmodontis infection (larval, juvenile adult, and patency), and the impact of co-infection was determined by IAV induced weight loss and clinical signs, quantification of viral titres, and helminth counts. Significant alterations of IAV pathogenesis, dependent upon stage of infection, was observed on co-infection with L. sigmodontis. Larval stage L. sigmodontis infection alleviated clinical signs of IAV co-infection, whilst more established juvenile adult infection also significantly delayed weight loss. Viral titres remained unaltered at either infection stage. In contrast, patent L. sigmdodontis infection led to a reversal of age-related resistance to IAV infection, significantly increasing weight loss and clinical signs of infection as well as increasing IAV titre. These data demonstrate that the progression of influenza infection can be ameliorated or worsened by pre-existing filarial infection, with the outcome dependent upon the stage of filarial infection.

RESUMO De julho a agosto de 2001, foram colhidas amostras de fezes de 95 cães (13,8% da população canina) da área urbana do Município de Monte Negro, Rondônia. As amostras de fezes foram examinadas pelos métodos coproparasitológicos de Willis, centrífugo-flutuação em solução de sacarose e centrífugo-sedimentação em água-éter. Das 95 amostras de fezes, somente 15 (15,8%) foram negativas. Foram encontrados helmintos pertencentes a 5 gêneros: Ancylostoma, Toxocara, Trichuris, Spirocerca, Physalopterae 5 protozoários: Sarcocystis, Giardia, Cystoisospora, Cryptosporidium, Hammondia-Neospora. Ovos de Ancylostoma spp. foram os mais prevalentes (73,7% de amostras positivas), seguidos por ovos de Toxocara canis (18,9%) e esporocistos de Sarcocystis spp. (18,9%). Os demais parasitos tiveram prevalências abaixo de 10%. Os resultados encontrados foram comparados com outros trabalhos brasileiros, demonstrando que o gênero Ancylostoma é o mais freqüentemente diagnosticado em cães no Brasil. ABSTRACT From July to August 2001, individual fecal samples were collected from 95 dogs (13.8% of the canine population) living in the urban area of Monte Negro, Rondônia. The fecal samples were processed by the following coproparasitological methods: Willis (simple flotation), centrifugal flotation employing sacarose solution, and centrifugal sedimentation employing water-ether. Only 15 (15.8%) out of 95 fecal samples were negative. Five helminth genera were found: Ancylostoma, Toxocara, Trichuris, Spirocerca, Physaloptera; as well as 5 protozoan genera: Sarcocystis, Giardia, Cystoisospora, Cryptosporidium, Hammondia-Neospora. Ancylostoma spp. eggs were the most prevalent (73.6% of positive samples), followed by Toxocara canis eggs (18.9%) and Sarcocystis spp. sporocysts (18.9%). Prevalence of the remaining parasites was less than 10%. The results were compared with other Brazilian studies, showing that the genus Ancylostoma is the most frequently found on dogs in Brazil.

The aim of this study was to investigate the ecology and diversity of community and infracommunities of metazoan parasites Geophagus altifrons (Heckel, 1840) in Rio Jari, in the state of Amapá, in the eastern Amazon region. From the total of 31 fish examined, 90.3% were parasitized by one or more species, collecting a total number of 806 parasites. The parasites species identified were: Sciadicleithrum geophagi, Posthodiplostomum sp., Procamallanus (Spirocamallanus) inopinatus, Raphidascaris (Sprentacaris) sp., Genarchella genarchella, Gorytocephalus spectabilis and Ergasilus xinguensis. Most of the parasites showed an aggregate dispersion pattern. Brillouin diversity index, uniformity and species richness of parasites were low. The component community of parasites was constituted by ectoparasites and endoparasites, but with a predominance of ectoparasites. The body size of hosts had a low effect on the parasites infracommunities. This first eco-epidemiological study for G. altifrons reports these parasites in a host, for the first time, with the exception of S. geophagi and E. xinguensis.

BackgroundAscaris infections, with a worldwide prevalence above 10%, can cause respiratory pathology. However, long-term effects on lung function in humans are largely unknown.ObjectiveWe investigated the associations of Ascaris exposure with lung function, asthma, and DNA methylation.MethodsSerum Ascaris IgG antibodies were measured in 671 adults aged 18 to 47 years (46% women) from Aarhus, Bergen, and Tartu RHINESSA study centers. Seropositivity was defined as IgG above the 90th percentile. Linear and logistic regressions were used to analyze Ascaris seropositivity as associated with lung function and asthma, adjusted for age, height, and smoking and clustered by center. DNA methylation in blood was profiled by a commercial methylation assay.ResultsAscaris seropositivity was associated with lower FEV1 (−247 mL; 95% CI, −460, −34) and higher odds for asthma (adjusted odds ratio, 5.84; 95% CI, 1.67, 20.37) among men but not women, also after further adjusting for house dust mite sensitivity, consistent across study centers. At a genome-wide level, Ascaris exposure was associated with 23 differentially methylated sites in men and 3 in women. We identified hypermethylation of the MYBPC1 gene, which can regulate airway muscle contraction. We also identified genes linked to asthma pathogenesis such as CRHR1 and GRK1, as well as a differentially methylated region in the PRSS22 gene linked to nematode infection.ConclusionAscaris exposure was associated with substantially lower lung function and increased asthma risk among men. Seropositive participants had sex-specific differences in DNA methylation compared to the unexposed, thus suggesting that exposure may lead to sex-specific epigenetic changes associated with lung pathology.

Helminths produce excretory/secretory products (E/S) which can modulate the immune responses of their hosts. Dendritic cells (DC) are essential for initiating the host T cell response and are thus potential targets for modulation by helminth E/S. Here we study immunomodulation of porcine peripheral blood DC subsets following ex vivo stimulation with E/S from Ascaris suum, a common helminth of pigs with considerable public health and economic importance. Our data showed that the relative frequencies of DC subsets in porcine blood differ, with plasmacytoid DC (pDC) being the most prominent in healthy 6-month-old pigs. pDC are an important cytokine source, and we found that A. suum E/S suppressed production of the type 1 cytokines IL-12p40 and TNF-α by this subset following toll-like receptor (TLR) ligation. In contrast, conventional DC (cDC) are more efficient antigen presenters, and the expression of CD80/86, costimulatory molecules essential for efficient antigen presentation, were modulated differentially by A. suum E/S between cDC subsets. CD80/86 expression by type 1 cDC (cDC1) following TLR ligation was greatly suppressed by the addition of A. suum E/S, while CD80/86 expression by type 2 cDC (cDC2) was upregulated by A. suum E/S. Further, we found that IFN-γ production by natural killer (NK) cells following IL-12 and IL-18 stimulation was suppressed by A. suum E/S. Finally, in the presence of E/S, IFN-γ production by CD4+ T cells co-cultured with autologous blood-derived DC was significantly impaired. Together, these data provide a coherent picture regarding the regulation of type 1 responses by A. suum E/S. Responsiveness of pDC and cDC1 to microbial ligands is reduced in the presence of E/S, effector functions of Th1 cells are impaired, and cytokine-driven IFN-γ release by NK cells is limited.

Increasing anthelmintic resistance (AR) in livestock has stimulated growing efforts to monitor anthelmintic effectiveness (AE) on livestock farms. On-farm assessment of AE relies on measuring the reduction in faecal egg count (FEC) following treatment; and if conducted rigorously, qualifies as a formal FEC reduction test (FECRT) for AR. Substantial research effort has been devoted to designing robust protocols for the FECRT and its statistical interpretation; however, a wide range of factors other than AR can affect FEC reduction on farms. These are not always possible to control, and can affect the outcome and repeatability of AE measurements and confound the on-farm classification of AR using FECRT. This review considers confounders of FEC reduction, focusing on gastrointestinal nematodes of ruminants, including host and parasite physiology and demography; pharmacokinetic variation between drugs, parasites and hosts; and technical performance. Drug formulation and delivery, host condition and diet, and seasonal variation in parasite species composition, can all affect AE and hence observed FEC reduction. Causes of variation in FEC reduction should be attenuated, but this is not always possible. Regular monitoring of AE can indicate a need to improve anthelmintic administration practices, and detect AR early in its progression. Careful interpretation of FEC reduction, however, taking into account possible confounders, is essential before attributing reduced FEC reduction to AR. Understanding of confounders of FEC reduction will complement advances in FECRT design and interpretation to provide measures of anthelmintic efficacy that are both rigorous and accessible.Facteurs de confusion affectant la réduction du nombre d’œufs fécaux comme mesure de l’efficacité anthelminthique.L’augmentation de la résistance aux anthelminthiques (RA) chez le bétail a stimulé des efforts croissants pour mesurer l’efficacité des anthelminthiques (EA) dans les élevages. L’évaluation à la ferme de l’EA repose sur la mesure de la réduction du nombre d’œufs dans les selles (NOS) après le traitement ; si effectué rigoureusement, celui-ci est qualifié de test formel de réduction du NOS (TFRNOS) pour la RA. Des efforts de recherche substantiels ont été consacrés à la conception de protocoles robustes pour le TFRNOS et son interprétation statistique, mais un large éventail de facteurs autres que la RA peuvent affecter la réduction du NOS dans les exploitations. Ces facteurs ne sont pas toujours contrôlables et peuvent affecter le résultat et la répétabilité des mesures de l’EA et introduire de la confusion dans la classification à la ferme de la RA à l’aide de la TFRNOS. Cette revue examine les facteurs de confusion de la réduction du NOS, en se concentrant sur les nématodes gastro-intestinaux des ruminants, et considère la physiologie et la démographie de l’hôte et du parasite, la variation pharmacocinétique entre les médicaments, les parasites et les hôtes, et les performances techniques. La formulation et l’administration de médicaments, la condition et le régime alimentaire de l’hôte, ainsi que les variations saisonnières de la composition des espèces de parasites, peuvent tous affecter l’EA et donc la réduction du NOS observé. Les causes de variation de la réduction du NOS doivent être atténuées, mais cela n’est pas toujours possible. Une surveillance régulière de l’EA peut indiquer la nécessité d’améliorer les pratiques d’administration des anthelminthiques et de détecter la RA au début de sa progression. Une interprétation prudente de la réduction du NOS, cependant, en tenant compte des facteurs de confusion possibles, est essentielle avant d’attribuer la réduction du NOS à la RA. La compréhension des facteurs de confusion d’une moindre réduction du NOS complétera les progrès sur la conception et l’interprétation du TFRNOS, pour fournir des mesures de l’efficacité des anthelminthiques à la fois rigoureuses et accessibles.

International audience; In free-range and organic production systems, hens can make choices according to their needs and desires, which is in accordance with welfare definitions. Nonetheless, health and behavioral problems are also encountered in these systems. The aim of this article was to identify welfare challenges observed in these production systems in the EU and the most promising solutions to overcome these challenges. It is based on a review of published literature and research projects complemented by interviews with experts. We selected EU specific information for welfare problems, however, the selected literature regarding solutions is global. Free range use may increase the risk of infection by some bacteria, viruses and parasites. Preventive methods include avoiding contamination thanks to biosecurity measures and strengthening animals' natural defenses against these diseases which can be based on nutritional means with new diet components such as insect-derived products, probiotics and prebiotics. Phytotherapy and aromatherapy can be used as preventive and curative medicine and vaccines as alternatives to antibiotics and pesticides. Bone quality in pullets and hens prevents keel deviations and is favored by exercise in the outdoor range. Free range use also lead to higher exposure to variable weather conditions and predators, therefore shadow, fences and guard animals can be used to prevent heat stress and predation respectively. Granting a free range provides opportunities for the expression of many behaviors and yet many hens usually stay close to the house. Providing the birds with trees, shelters or attractive plants can increase range use. Small flock sizes, early experiences of enrichment and personality traits have also been found to enhance range use. Severe feather pecking can occur in free range production systems, although flocks using the outdoor area have better plumage than indoors. While many prevention strategies are facilitated in free range systems, the influence of genetics, prenatal and nutritional factors in free range hens still need to be investigated. This review provides information about practices that have been tested or still need to be explored and this information can be used by stakeholders and researchers to help them evaluate the applicability of these solutions for welfare improvement.