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PLoS Pathogens May 2024The eggs of the blood fluke Schistosoma mansoni are the main cause of the clinical manifestations of chronic schistosomiasis. After laying, the egg "winners" attach to...
The eggs of the blood fluke Schistosoma mansoni are the main cause of the clinical manifestations of chronic schistosomiasis. After laying, the egg "winners" attach to the endothelium of the mesenteric vein and, after a period of development, induce the growth of a small granuloma, which facilitates their passage to the intestinal lumen. Egg "losers" carried by the bloodstream to non-specific tissues also undergo full development and induce large granuloma formation, but their life ends there. Although these trapped eggs represent a dead end in the parasite life cycle, the vast majority of studies attempting to describe the biology of the S. mansoni eggs have studied these liver-trapped "losers" instead of migrating intestinal "winners". This raises the fundamental question of how these eggs differ. With robust comparative transcriptomic analysis performed on S. mansoni eggs isolated 7 weeks post infection, we show that gene expression is critically dependent on tissue localization, both in the early and late stages of development. While mitochondrial genes and venom allergen-like proteins are significantly upregulated in mature intestinal eggs, well-described egg immunomodulators IPSE/alpha-1 and omega-1, together with micro-exon genes, are predominantly expressed in liver eggs. In addition, several proteases and protease inhibitors previously implicated in egg-host interactions display clear tissue-specific gene expression patterns. These major differences in gene expression could be then reflected in the observed different ability of liver and intestinal soluble egg antigens to elicit host immune responses and in the shorter viability of miracidia hatched from liver eggs. Our comparative analysis provides a new perspective on the biology of parasite's eggs in the context of their development and tissue localization. These findings could contribute to a broader and more accurate understanding of parasite eggs interactions with the host, which have historically been often restricted to liver eggs and sometimes inaccurately generalized.
PubMed: 38814989
DOI: 10.1371/journal.ppat.1012268 -
International Journal For Parasitology.... Aug 2024The municipality of Sumidouro in the state of Rio de Janeiro, southeastern Brazil, is considered an area with low endemicity of . In this municipality, the wild water...
The municipality of Sumidouro in the state of Rio de Janeiro, southeastern Brazil, is considered an area with low endemicity of . In this municipality, the wild water rat is a wild reservoir of . A helminth community survey was carried out on populations in Sumidouro from 1997 to 1999. In the present study, we compared the helminth fauna and the helminth community structure of with a recent survey after a 22-year time interval, considering that the prevalence of infection in humans remained stable and that the area showed the same environmental characteristics. Seventy-three host specimens of collected between 1997 and 1999 and 21 specimens collected in 2021 were analyzed in this study. Seven helminth species were found in each collection period. The nematode was recorded for the first time in in 2021. was the most abundant species in both periods and the most prevalent in 2021. During the period from 1997 to 1999, the most prevalent species was . Significant differences in prevalence and abundance in relation to host sex were observed only for in 1997-1999. Significant differences in the abundance of the helminth species over time were observed only in , and were the dominant species in both periods. and became dominant, codominant and subordinate, respectively, over time. In conclusion, the helminth community of remained stable, with similar species richness, prevalence and abundance values and low beta-diversity over time. The occurrence of in the water rat has remained stable for decades, highlighting its importance for schistosomiasis control.
PubMed: 38807751
DOI: 10.1016/j.ijppaw.2024.100941 -
PLoS Pathogens May 2024The common liver fluke (Fasciola hepatica) causes the disease fasciolosis, which results in considerable losses within the global agri-food industry. There is a...
The common liver fluke (Fasciola hepatica) causes the disease fasciolosis, which results in considerable losses within the global agri-food industry. There is a shortfall in the drugs that are effective against both the adult and juvenile life stages within the mammalian host, such that new drug targets are needed. Over the last decade the stem cells of parasitic flatworms have emerged as reservoirs of putative novel targets due to their role in development and homeostasis, including at host-parasite interfaces. Here, we investigate and characterise the proliferating cells that underpin development in F. hepatica. We provide evidence that these cells are capable of self-renewal, differentiation, and are sensitive to ionising radiation-all attributes of neoblasts in other flatworms. Changes in cell proliferation were also noted during the early stages of in vitro juvenile growth/development (around four to seven days post excystment), which coincided with a marked reduction in the nuclear area of proliferating cells. Furthermore, we generated transcriptomes from worms following irradiation-based ablation of neoblasts, identifying 124 significantly downregulated transcripts, including known stem cell markers such as fgfrA and plk1. Sixty-eight of these had homologues associated with neoblast-like cells in Schistosoma mansoni. Finally, RNA interference mediated knockdown of histone h2b (a marker of proliferating cells), ablated neoblast-like cells and impaired worm development in vitro. In summary, this work demonstrates that the proliferating cells of F. hepatica are equivalent to neoblasts of other flatworm species and demonstrate that they may serve as attractive targets for novel anthelmintics.
PubMed: 38805551
DOI: 10.1371/journal.ppat.1011903 -
Pharmaceuticals (Basel, Switzerland) Apr 2024Leishmaniasis, produced by spp., and Chagas disease, produced by , affect millions of people around the world. The treatments for these pathologies are not entirely...
Leishmaniasis, produced by spp., and Chagas disease, produced by , affect millions of people around the world. The treatments for these pathologies are not entirely effective and produce some side effects. For these reasons, it is necessary to develop new therapies that are more active and less toxic for patients. Some initiatives, such as the one carried out by the Medicines for Malaria Venture, allow for the screening of a large number of compounds of different origins to find alternatives to the lack of trypanocide treatments. In this work, 240 compounds were tested from the Global Health Priority Box (80 compounds with confirmed activity against drug-resistant malaria, 80 compounds for screening against neglected and zoonotic diseases and diseases at risk of drug resistance, and 80 compounds with activity against various vector species) against and . Flucofuron, a compound with activity against vectors and with previous activity reported against spp. and spp., demonstrates activity against and and produces programmed cell death in the parasites. Flucofuron seems to be a good candidate for continuing study and proving its use as a trypanocidal agent.
PubMed: 38794125
DOI: 10.3390/ph17050554 -
Microorganisms May 2024Multiple microbial detections in stool samples of indigenous individuals suffering from chronic gastroenteric disorder of a likely infectious origin, characterized by...
Collider Bias Assessment in Colombian Indigenous Wiwa and Kogui Populations with Chronic Gastroenteric Disorder of Likely Infectious Etiology Suggests Complex Microbial Interactions Rather Than Clear Assignments of Etiological Relevance.
Multiple microbial detections in stool samples of indigenous individuals suffering from chronic gastroenteric disorder of a likely infectious origin, characterized by recurring diarrhea of variable intensity, in the rural north-east of Colombia are common findings, making the assignment of etiological relevance to individual pathogens challenging. In a population of 773 indigenous people from either the tribe Wiwa or Kogui, collider bias analysis was conducted comprising 32 assessed microorganisms including 10 bacteria ( spp., spp., enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), spp., Shiga toxin-producing (STEC), spp./enteroinvasive (EIEC), and spp.), 11 protozoa ( spp., spp., spp., , , /// complex, , , , and ), 8 helminths ( spp., , spp., , spp., spp., spp. and spp.), microsporidia ( spp.) and fungal elements (microscopically observed conidia and pseudoconidia). The main results indicated that negative associations potentially pointing towards collider bias were infrequent events (n = 14), while positive associations indicating increased likelihood of co-occurrence of microorganisms quantitatively dominated (n = 88). Microorganisms showing the most frequent negative associations were EPEC (n = 6) and spp. (n = 3), while positive associations were most common for spp. (n = 16), (n = 15), spp./EIEC (n = 12), spp. (n = 11) and spp. (n = 10). Of note, positive associations quantitively dominated for spp. In conclusion, collider bias assessment did not allow clear-cut assignment of etiological relevance for detected enteric microorganisms within the assessed Colombian indigenous population. Instead, the results suggested complex microbial interactions with potential summative effects. Future studies applying alternative biostatistical approaches should be considered to further delineate respective interactions.
PubMed: 38792799
DOI: 10.3390/microorganisms12050970 -
Diagnostics (Basel, Switzerland) May 2024Urine filtration microscopy (UFM) lacks sensitivity in detecting low-intensity infections. In pursuit of a superior alternative, this study evaluated the performance of...
Urine filtration microscopy (UFM) lacks sensitivity in detecting low-intensity infections. In pursuit of a superior alternative, this study evaluated the performance of FlukeCatcher microscopy (FCM) at detecting eggs in human urine samples. Urine samples were collected from 572 school-age children in Afar, Ethiopia in July 2023 and examined using UFM and FCM approaches. Using the combined UFM and FCM results as a reference, the sensitivity, negative predictive value, and agreement levels for the two testing methods in detecting eggs in urine samples were calculated. The sensitivity and negative predictive value of detecting eggs in urine samples for FCM was 84% and 97%, respectively, compared to 65% and 93% for UFM. The FCM test results had an agreement of 61% with the UFM results, compared to 90% with the combined results of FCM and UFM. However, the average egg count estimates were lower when using FCM (6.6 eggs per 10 mL) compared to UFM (14.7 eggs per 10 mL) ( < 0.0001). Incorporating FCM into specimen processing could improve the diagnosis of infection but may underperform in characterizing the intensity of infection.
PubMed: 38786335
DOI: 10.3390/diagnostics14101037 -
Emerging Infectious Diseases Jun 2024A fecal survey in Tamil Nadu, India, revealed 2 persons passed schistosome eggs, later identified as Schistosoma incognitum, a parasite of pigs, dogs, and rats. We... (Review)
Review
A fecal survey in Tamil Nadu, India, revealed 2 persons passed schistosome eggs, later identified as Schistosoma incognitum, a parasite of pigs, dogs, and rats. We investigated those cases and reviewed autochthonous schistosomiasis cases from India and Nepal. Whether the 2 new cases represent true infection or spurious passage is undetermined.
Topics: Animals; India; Humans; Schistosoma; Schistosomiasis; Feces; Male; Female; Dogs; Adult; Swine; Rats; Nepal; Middle Aged; Asia, Southern
PubMed: 38782022
DOI: 10.3201/eid3006.231641 -
Frontiers in Immunology 2024Schistosomiasis is a common cause of pulmonary hypertension (PH) worldwide. Type 2 inflammation contributes to the development of Schistosoma-induced PH. Specifically,...
BACKGROUND
Schistosomiasis is a common cause of pulmonary hypertension (PH) worldwide. Type 2 inflammation contributes to the development of Schistosoma-induced PH. Specifically, interstitial macrophages (IMs) derived from monocytes play a pivotal role by producing thrombospondin-1 (TSP-1), which in turn activates TGF-β, thereby driving the pathology of PH. Resident and recruited IM subpopulations have recently been identified. We hypothesized that in Schistosoma-PH, one IM subpopulation expresses monocyte recruitment factors, whereas recruited monocytes become a separate IM subpopulation that expresses TSP-1.
METHODS
Mice were intraperitoneally sensitized and then intravenously challenged with S. mansoni eggs. Flow cytometry on lungs and blood was performed on wildtype and reporter mice to identify IM subpopulations and protein expression. Single-cell RNA sequencing (scRNAseq) was performed on flow-sorted IMs from unexposed and at day 1, 3 and 7 following Schistosoma exposure to complement flow cytometry based IM characterization and identify gene expression.
RESULTS
Flow cytometry and scRNAseq both identified 3 IM subpopulations, characterized by CCR2, MHCII, and FOLR2 expression. Following exposure, the CCR2 IM subpopulation expanded, suggestive of circulating monocyte recruitment. exposure caused increased monocyte-recruitment ligand CCL2 expression in the resident FOLR2 IM subpopulation. In contrast, the vascular pathology-driving protein TSP-1 was greatest in the CCR2 IM subpopulation.
CONCLUSION
-induced PH involves crosstalk between IM subpopulations, with increased expression of monocyte recruitment ligands by resident FOLR2 IMs, and the recruitment of CCR2 IMs which express TSP-1 that activates TGF-β and causes PH.
Topics: Animals; Hypertension, Pulmonary; Mice; Macrophages; Phenotype; Schistosoma mansoni; Mice, Inbred C57BL; Schistosomiasis; Disease Models, Animal; Schistosomiasis mansoni; Thrombospondin 1; Monocytes; Receptors, CCR2; Female; Schistosoma; Lung
PubMed: 38779688
DOI: 10.3389/fimmu.2024.1372957 -
Frontiers in Plant Science 2024In the realm of nanotechnology, the use of algae to produce nanoparticles is an environmentally friendly, sustainable, and economically viable strategy. In the present...
In the realm of nanotechnology, the use of algae to produce nanoparticles is an environmentally friendly, sustainable, and economically viable strategy. In the present study, the brown macroalgae was utilized to effectively produce silver nanoparticles (AgNPs). Through various characterization techniques, the AgNPs' structural integrity was confirmed. AgNPs exhibited significant antimicrobial activity against and . AgNPs showed cytotoxic effects on the MCF-7 breast adenocarcinoma cell line with an IC of 12.5 µg/ml. Treatment with AgNPs resulted in a marked reduction in cell viability, alongside evident apoptotic and necrotic morphological changes in the cancer cells. Through molecular docking studies, a deeper understanding of the interaction between AgNPs and crucial proteins related to cancer has been achieved, AgNPs showed a promising molluscicidal action on snails, a intermediate host. The half-lethal dose (LC) of AgNPs was determined to be 0.84 mg/L. The potential consequences of its administration include potential disruptions to the glycolysis profile, as well as potential impacts on the steroidal hormone's estrogen and testosterone and certain kidney function tests. This study highlights the diverse uses of algae-synthesized AgNPs, ranging from healthcare to environmental management, demonstrating their importance in advancing nano-biotechnological solutions.
PubMed: 38779072
DOI: 10.3389/fpls.2024.1403753 -
Parasites & Vectors May 2024Snail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for...
BACKGROUND
Snail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for effective control. Given the dearth of knowledge on African trematodes, this study aimed to map snail and trematode diversity, focusing on (i) characterizing gastropod snail species and their trematode parasites, (ii) determining infection rates of snail species as intermediate hosts for medically, veterinary, and ecologically significant trematodes, and (iii) comparing their diversity across endemic regions.
METHODS
A cross-sectional study conducted in 2021 in Chiredzi and Wedza districts in Zimbabwe, known for high human schistosomiasis prevalence, involved malacological surveys at 56 sites. Trematode infections in snails were detected through shedding experiments and multiplex rapid diagnostic polymerase chain reactions (RD-PCRs). Morphological and molecular analyses were employed to identify snail and trematode species.
RESULTS
Among 3209 collected snail specimens, 11 species were identified, including schistosome and fasciolid competent snail species. We report for the first time the invasive exotic snail Tarebia granifera in Zimbabwe, which was highly abundant, mainly in Chiredzi, occurring at 29 out of 35 sites. Shedding experiments on 1303 snails revealed a 2.24% infection rate, with 15 trematode species identified through molecular genotyping. Five species were exclusive to Chiredzi: Bolbophorus sp., Schistosoma mansoni, Schistosoma mattheei, Calicophoron sp., and Uvulifer sp. Eight were exclusive to Wedza, including Trichobilharzia sp., Stephanoprora amurensis, Spirorchid sp., and Echinostoma sp. as well as an unidentified species of the Plagiorchioidea superfamily. One species, Tylodelphys mashonensis, was common to both regions. The RD-PCR screening of 976 non-shedding snails indicated a 35.7% trematode infection rate, including the presence of schistosomes (1.1%) Fasciola nyanzae (0.6%). In Chiredzi, Radix natalensis had the highest trematode infection prevalence (33.3%), while in Wedza, R. natalensis (55.4%) and Bulinus tropicus (53.2%) had the highest infection prevalence.
CONCLUSIONS
Our xenomonitoring approach unveiled 15 trematode species, including nine new records in Zimbabwe. Schistosoma mansoni persists in the study region despite six mass deworming rounds. The high snail and parasite diversity, including the presence of exotic snail species that can impact endemic species and biomedically important trematodes, underscores the need for increased monitoring.
Topics: Animals; Zimbabwe; Snails; Trematoda; Cross-Sectional Studies; Introduced Species; Fresh Water; One Health; Humans; Trematode Infections; Biodiversity; Prevalence; Schistosomiasis
PubMed: 38773521
DOI: 10.1186/s13071-024-06307-4