International journal for parasitology最新文献

{"title":"Trichinella spiralis extracellular vesicles induce anti-inflammatory and regulatory immune responses in vitro.","authors":"Sofija Glamočlija, Ljiljana Sabljić, Sergej Tomić, Jelena Đokić, Nataša Radulović, Alisa Gruden-Movsesijan, Maja Kosanović","doi":"10.1016/j.ijpara.2025.01.008","DOIUrl":"10.1016/j.ijpara.2025.01.008","url":null,"abstract":"<p><p>The helminth Trichinella spiralis, through its excretory-secretory (ES L1) products, induces immune regulatory mechanisms that modulate the host's immune response not only to itself, but also to bystander antigens, foreign or self in origin, which can result in the alleviation of inflammatory diseases. Under the influence of ES L1, dendritic cells (DCs) acquire a tolerogenic phenotype and the capacity to induce Th2 and regulatory responses. Since ES L1 products represent a complex mixture of proteins and extracellular vesicles (TsEVs) the aim of this study was to investigate the impact of TsEVs, isolated from ES L1 products, on phenotypic and functional characteristics of DCs and to elucidate whether TsEVs could reproduce the immunomodulatory effects of the complete ES L1 product. Monocyte-derived DCs treated with TsEVs acquired semi-matured phenotypes, characterized by low expression of human leukocyte antigen - DR isotype (HLA-DR), cluster of differentiation (CD) 86 (CD86), and CD40, moderate expression of CD83 and C-C chemokine receptor type 7 (CCR7), and increased expression of tolerogenic markers indoleamine 2,3-dioxygenase 1 (IDO-1) and immunoglobulin-like transcript 3 (ILT3), together with the unchanged production of IL-12 and IL-23, and elevated production of IL-10 and transforming growth factor (TGF)-β, compared with controls. Gene expression analysis of TsEV-treated DCs revealed elevated levels of mTOR, Ahr, NF-κB2, RelB, SOCS1 and SOCS3, which participate in signaling pathways involved in DC maturation and the subsequent regulation of release of both anti-inflammatory and pro-inflammatory cytokines. TsEVs promoted the capacity of DCs to drive polarization of Th2 and anti-inflammatory responses, and impaired their capacity to induce Th1/Th17 polarization. Moreover, TsEV-treated DCs possessed a high capacity to induce conventional FoxP3 + regulatory T cells, as well as unconventional T regulatory (Tr1) cells. Tolerogenic properties of TsEV-treated DCs were retained even after challenge with a pro-inflammatory stimulus. These findings highlight the potential of TsEVs to induce immune tolerance, suggesting their potential use as therapeutics for the treatment of inflammatory disorders.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143023342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extensive transcriptional differentiation and specialization of a single-host parasite aligns with niche turnover generated by its host's metamorphosis.","authors":"James G DuBose, Jacobus C de Roode","doi":"10.1016/j.ijpara.2025.01.006","DOIUrl":"10.1016/j.ijpara.2025.01.006","url":null,"abstract":"<p><p>Foundational theory on life cycle evolution suggests that given genetic independence, the phenotypes presented by different life stages will diverge more when they occupy more distinct niches. When divergence between stages is significant and punctual, we typically consider the life cycle complex. In parasites, the delineation between simple and complex life cycles is usually made between those that utilize single and multiple host species. However, many parasites can experience significant niche shifts in a single host. To explore the potential for a host's metamorphosis to shape divergence between stages across its parasite's life cycle, we quantified the transcriptional differentiation and specialization that the protozoan parasite Ophryocystis elektroscirrha exhibits across the metamorphosis of its host, the monarch butterfly. We found evidence that O. elektroscirrha differentiates in concordance with the ecological turnover imposed by monarch transitions to different stages, and that patterns of transcriptional decoupling across O. elektroscirrha exceeded even those of its host. However, due to its greater gene content, the monarch butterfly exhibited greater total transcriptional turnover than its parasite. These findings suggest that a deeper understanding of life cycle evolution for both free-living and parasitic lifestyles may be facilitated by more nuanced and continuous descriptions of life cycle complexity.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143023333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genome assembly variation and its implications for gene discovery in nematodes.","authors":"Grace M Mariene, James D Wasmuth","doi":"10.1016/j.ijpara.2025.01.004","DOIUrl":"10.1016/j.ijpara.2025.01.004","url":null,"abstract":"<p><p>Genome assemblers are a critical component of genome science, but the choice of assembly software and protocols can be daunting. Here, we investigate genome assembly variation and its implications for gene discovery across three nematode species-Caenorhabditis bovis, Haemonchus contortus, and Heligmosomoides bakeri-highlighting the critical interplay between assembly choice and downstream genomic analysis. Selecting commonly used genome assemblers, we generated multiple assemblies for each species, analyzing their structure, completeness, and effect on gene family analysis. Our findings demonstrate that assembly variations can significantly affect gene family composition, with notable differences in gene families important in anthelmintic discovery and immunomodulation. Despite broadly similar performance using various assembly metrics, comparisons of assemblies with a single species revealed underlying structural rearrangements and inconsistencies in gene content, which would affect downstream analyses. This emphasizes the need for continuous refinement of genome assemblies and their annotations.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular detection of trypanosomatids among cave-dwelling bats from Colombia.","authors":"J Manuel Matiz-González, Carlos Ramiro Silva-Ramos, María T Herrera-Sepúlveda, Luz Helena Patiño, Juan David Ramírez, Jose Mateus, Paula X Pavia, C Miguel Pinto, Jairo Pérez-Torres, Claudia Cuervo","doi":"10.1016/j.ijpara.2025.01.005","DOIUrl":"10.1016/j.ijpara.2025.01.005","url":null,"abstract":"<p><p>Bats play crucial roles in various ecosystems including caves. Although the presence of trypanosomatid species in bats has been documented in Colombia, their diversity in cave-dwelling bats remains unclear. This study aimed to characterize the frequency and diversity of protists from the family Trypanosomatidae circulating in bats from the Macaregua cave ecosystem in Santander, Colombia. A total of 112 specimens from the three permanently residing bat species were examined for trypanosomatid presence through the amplification and sequencing of a region of the 18S rRNA gene in blood samples. We report an overall trypanosomatid detection rate of 42.9% (n = 48), involving the three evaluated bat species: Carollia perspicillata (19/43, 44.2%), Natalus tumidirostris (17/39, 43.6%), and Mormoops megalophylla (12/30, 40.0%). The trypanosomatids were classified by amplicon sequencing and phylogenetic analysis as Trypanosoma spp. (33/112, 29.5%), Leishmania spp. (8/112, 7.1%), and Crithidia spp. (9/112, 8%). In addition, two individuals simultaneously carried more than one genus: Trypanosoma and Leishmania (MT087, C. perspicillata), and Trypanosoma and Crithidia (MT120, M. megalophylla). Some of the samples positive for trypanosomatids were characterized at the species level using the same method with the Cytochrome B gene, identifying Trypanosoma cruzi cruzi (TcI-III and TcBat), Trypanosoma cruzi marinkellei, and Leishmania braziliensis in the evaluated bats. We describe the presence of pathogenic trypanosomatids (T. cruzi cruzi, T. cruzi marinkellei, and L. braziliensis), as well as monoxenous trypanosomatids such as Crithidia spp. as the Trypanosomatidae protists carried by bats in cave ecosystems from Colombia. The discussion on how bats become infected by these parasites and their potential role in wild transmission cycles is provided below.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and population structure of Oncomelania hupensis in Sichuan Province, China: implications for schistosomiasis control.","authors":"Jingye Shang, Liang Xu, Bo Zhong, Zisong Wu, Lin Chen, Xianhong Meng, Jiajia Wan, Yu Zhang, Chen Pu, Peijun Qian, Shizhu Li, Yang Liu","doi":"10.1016/j.ijpara.2025.01.003","DOIUrl":"10.1016/j.ijpara.2025.01.003","url":null,"abstract":"<p><p>Schistosomiasis, caused by the infection with Schistosoma japonicum, remains a significant public health concern in China. As the sole intermediate host of S. japonicum, the breeding and spread of Oncomelania hupensis contribute significantly to the potential risk of disease occurrence and transmission. Exploring the population genetics of the snail vector is conducive to better understanding its distribution and dispersal patterns, and provides more data for future snail surveillance and control from a molecular perspective. The genetic diversity and population structure of O. hupensis in Sichuan Province were evaluated based on sequencing of mitochondrial cytochrome c oxidase subunit 1. A total of 215 snail isolates were collected from 30 counties, identifying 80 haplotypes with high nucleotide diversity (0.05871 ± 0.00160) and haplotype diversity (0.979 ± 0.003). Phylogenetic analysis and haplotype network construction identified five distinct clades. Notably, clade 1 was confined within the Panxi region, while clade 5 exhibited a widespread distribution across the studied areas, distinct from the other four clades, but showing a close genetic relationship to individuals from Yunnan. Spatial differentiation was revealed by significant pairwise genetic distance values detected in 313 out of 435 population pairs, ranging from 0.07632 to 1.00000. Analysis of molecular variance (AMOVA) showed that the majority of variance occurred among populations, but significant differences were also observed among landscape groups. AMOVA also provided support for clade separation by exhibiting significant genetic differences among the clades, which explained 78.23% of the overall variation. Geographical distance and precipitation were found to display a significant correlation with the genetic differentiation pattern of O. hupensis in both Mantel and partial Mantel tests. Temporal stability was observed over sampling intervals of 7 years, particularly among snail populations inhabiting the Panxi area, despite prolonged molluscicide treatment. This study provides updated insights into the genetic diversity and population structure of O. hupensis in Sichuan Province, which contribute to a better understanding of the challenges faced in snail control. In light of the findings, the integration of molecular insights into snail monitoring and control, and the reinforcement of collaborative efforts in neighboring regions, in addition to long-distance monitoring, are suggested.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143004905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and intercontinental dispersal of temperate and subarctic populations of Dibothriocephalus dendriticus (Cestoda; Diphyllobothriidea), a causative agent of dibothriocephalosis.","authors":"Ivica Králová-Hromadová, Eva Čisovská Bazsalovicsová, Alžbeta Radačovská, Katarína Šoltys, Ľudmila Juhásová, Gabriel Minárik, Roman Kuchta, Karl Skírnisson, Egil Karlsbakk, Jan Štefka","doi":"10.1016/j.ijpara.2025.01.002","DOIUrl":"10.1016/j.ijpara.2025.01.002","url":null,"abstract":"<p><p>The diphyllobothriid tapeworm Dibothriocephalus dendriticus, one of the causative agents of the fish-borne zoonosis dibothriocephalosis, is mainly distributed in the Arctic/subarctic and temperate zones of the Northern Hemisphere (Europe, North America, and Asia), but also in the southern cone region of South America (Patagonia). The genetic structure and gene flow among 589 individuals of D. dendriticus, representing 20 populations, were studied using the mitochondrial cox1 gene as the first choice marker and 10 polymorphic nuclear microsatellite loci as a dominant molecular tool. The haplotype network of 30 cox1 haplotypes and Principal Coordinate Analysis/Structure analysis based on microsatellite data revealed close genetic relationships among populations within continents, namely northern and northwestern Europe (Norway, Finland, and UK/Scotland), North America (USA/Alaska, USA/Oregon, and Greenland), and South America (Argentina and Chile). The population from Iceland, located on the Mid-Atlantic Ridge between North America and Europe, was related to both Europe and North America. The mixed Nearctic and Palaearctic origin of D. dendriticus in Iceland was confirmed by a coalescent-based analysis of the microsatellite loci (in Migrate software). The most likely scenarios suggested that the Icelandic population is a genetic admixture of tapeworms from northwestern Europe and USA/Alaska. These findings corresponded with the distribution and migratory routes of piscivorous birds of the family Laridae, the main definitive hosts of D. dendriticus. The origin of an apparently non-native population of D. dendriticus in Patagonia was investigated in detail. The two most plausible hypotheses based on Migrate analysis represented different scenarios. One of them points to a European origin of the Patagonian population, the other to a North American origin. Future research with more extensive and a geographically broader sampling set is recommended to trace dispersal routes of D. dendriticus in Patagonia.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142970609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variations in extracellular vesicle shedding of Cystoisospora suis stages (Apicomplexa: Coccidia).","authors":"Anna Sophia Feix, Astrid Laimer-Digruber, Teresa Cruz-Bustos, Gerhard Steiner, Bärbel Ruttkowski, Monika Ehling-Schulz, Anja Joachim","doi":"10.1016/j.ijpara.2025.01.001","DOIUrl":"10.1016/j.ijpara.2025.01.001","url":null,"abstract":"<p><p>Cystoisospora suis, a porcine enteral parasite of the order Coccidia, is characterized by a complex life cycle, with asexual and sexual development in the epithelium of the host gut and an environmental phase as an oocyst. All developmental stages vary greatly in their morphology and function, and therefore excrete different bioactive molecules for intercellular communication. Due to their complex development, we hypothesized that the extracellular vesicles (EVs) cargo is highly dependent on the life cycle stages from which they are released. This study aimed to characterize and compare EVs of all developmental stages of C. suis. Nanoparticle tracking analysis and microscopy were used to determine particle numbers and size distributions of stage-specific parasite EVs. Furthermore, Fourier-transform infrared spectral analysis was employed for the metabolic fingerprinting of EVs, and the lipid and protein profiles of all parasite stages were determined. Overall, the study revealed that asexual, sexual and transmissible stages of C. suis release different EVs during the parasite's life cycle. EVs of endogenous asexual and sexual stages were found to be more similar to each other than to those of the transmissible environmental stage, the oocyst. Furthermore, the ratio of fatty acids to polysaccharides and proteins changed during parasite development. In particular, proteins associated with the Apicomplexa and those involved in vesicle shedding showed changes in expression in all parasite stages. Lipid analysis showed that fatty acids were found in the same concentration through all parasite stages, whereas the amount of stereolipids, sphingolipids and glycerolipids changed between the parasite stages. In conclusion, this study, which presents the first known characterization of C. suis EVs, demonstrates a link between EVs and the respective developmental stages of the parasite, and putative functions in the parasite-parasite and host-parasite interplays.</p>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142964502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A footworm in the door: revising Onchocerca phylogeny with previously unknown cryptic species in wild North American ungulates","authors":"Matthew R. Kulpa ,&nbsp;Emilie Lefoulon ,&nbsp;Kimberlee B. Beckmen ,&nbsp;Samantha E. Allen ,&nbsp;Jennifer Malmberg ,&nbsp;John A. Crouse ,&nbsp;Daniel P. Thompson ,&nbsp;Bridgett M. Benedict ,&nbsp;Dayna A. Goldsmith ,&nbsp;Sara McCarthy ,&nbsp;Lee C. Jones ,&nbsp;Michael J. Yabsley ,&nbsp;James M. Crum ,&nbsp;Susan J. Kutz ,&nbsp;Guilherme G. Verocai","doi":"10.1016/j.ijpara.2024.10.006","DOIUrl":"10.1016/j.ijpara.2024.10.006","url":null,"abstract":"<div><div><em>Onchocerca</em> is an important genus of vector-borne filarial nematodes that infect both humans and animals worldwide. Many <em>Onchocerca</em> spp., most of medical and veterinary health relevance, are the focus of a variety of diagnostic and molecular research. However, despite the importance of these parasites, there is growing evidence of previously unexplored genetic diversity of these nematodes, particularly among wild ungulate hosts in North America. These understudied parasites prevent us from comprehending the evolutionary history of the genus <em>Onchocerca</em>, monitoring potential One Health threats, and improving our filarioid diagnostic capabilities. In order to fill these knowledge gaps, we identified five uncharacterized <em>Onchocerca</em> lineages and compared them with other well-known filarioid species using single and concatenated gene regions (i.e., <em>nd5</em>, <em>cox1</em>, 12S, 18S, 28S, <em>hsp70</em>, <em>MyoHC</em>, <em>rbp1</em>). Phylogenetic analyses revealed that the novel <em>Onchocerca</em> lineages of wild North American ungulates segregate into two clades. One clade comprised <em>Onchocerca</em> lineages II, IV, and V and other species found mainly in domestic animals and humans, and the second comprised <em>Onchocerca</em> lineages I and III and other species from a variety of hosts including cervids, bovids, and equids. The formation of two clearly separate clades supports the idea of at least two independent expansion events of ancestral <em>Onchocerca</em> spp. into the North American continent via the Bering land bridge. Cophylogenetic analysis shows evidence of ancestral <em>Onchocerca</em> spp. of Bovidae host-switching to wild Cervidae and giving rise to the novel <em>Onchocerca</em> spp. Lastly, pairwise analysis confirms informative molecular markers of diagnostic relevance in both mitochondrial and nuclear gene regions of filarioid nematodes. The overall information provides greater context to the genus <em>Onchocerca</em> and emphasizes the need to discover, characterize, and monitor neglected parasites, especially those of wildlife origin.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 1","pages":"Pages 59-68"},"PeriodicalIF":3.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142619798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The microRNAome of Strongylus vulgaris larvae and their excretory/secretory products with identification of parasite-derived microRNAs in horse arterial tissue","authors":"Katrine Toft ,&nbsp;Marie Louise Honoré ,&nbsp;Nichol E. Ripley ,&nbsp;Martin K. Nielsen ,&nbsp;Bastian Fromm ,&nbsp;Maibritt Mardahl ,&nbsp;Lise N. Nielsen ,&nbsp;Peter Nejsum ,&nbsp;Stig Milan Thamsborg ,&nbsp;Susanna Cirera ,&nbsp;Tina Holberg Pihl","doi":"10.1016/j.ijpara.2024.10.005","DOIUrl":"10.1016/j.ijpara.2024.10.005","url":null,"abstract":"<div><div>The equine bloodworm, <em>Strongylus vulgaris</em>, is a highly pathogenic parasite causing potentially fatal vascular and intestinal damage. Parasites express and release microRNAs (miRNAs) for internal regulation and to modulate host immunity. The complete set of miRNAs expressed by <em>S. vulgaris</em> (the <em>S. vulgaris</em> miRNAome) remains unannotated and the aim of this study was to annotate the miRNAome of L4 and L5 stages of <em>S. vulgaris,</em> and to examine differences in miRNA abundance between larval stages and sexes. Furthermore, we aimed to determine if miRNAs were detectable in excretory/secretory products (ESPs) from larvae and in arterial tissue from their predilection site, the cranial mesenteric artery (CMA). Larvae were collected from naturally infected foals, and categorized by sex and stage. A subset of larvae was snap-frozen, while those remaining were incubated and the (ESPs) collected. Arterial tissue samples were collected from the CMA. Small RNA sequencing, followed by a custom bioinformatic pipeline, was used for annotation. We identified 142 <em>S. vulgaris</em> miRNAs in larvae and 136 in ESPs. Significant differences in miRNA abundance were observed between larvae and ESPs, and between L5 females (L5Fs) and L5 males (L5Ms), L4s and L5Fs, and L4s and L5Ms. No differences were found between L4s and L5s overall. In ESPs, several miRNAs were differentially abundant across all groups. Validation through quantitative real-time PCR (qPCR) detected selected miRNAs and their differential abundance in larvae and ESPs. One parasite-derived miRNA was detected in some of the horse arterial tissue samples but at very low levels. This study provided the first annotation of the <em>S. vulgaris</em> miRNAome. Most of the annotated larval miRNAs were also detectable in ESPs, and differences in miRNA abundance between sexes were found for larvae, and between sexes and stages for ESPs. Parasite-derived miRNAs were, however, not consistently detectable in the surrounding host arterial tissue.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 1","pages":"Pages 45-58"},"PeriodicalIF":3.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Different life strategies of closely related louse species in sympatry: specialist and “generalist“ lineages of Polyplax serrata","authors":"Jana Martinů ,&nbsp;Jan Štefka ,&nbsp;Kateřina Vránková ,&nbsp;Václav Hypša","doi":"10.1016/j.ijpara.2024.10.003","DOIUrl":"10.1016/j.ijpara.2024.10.003","url":null,"abstract":"<div><div>The origin and significance of host specificity are intriguing questions in parasitology. In the case of single-host versus multiple-host parasites, this topic integrates with the concept of the specialist/generalist trade-off. We use the model of sucking lice <em>Polyplax serrata</em> and rodent hosts <em>Apodemus</em>, to address these concepts. <em>Polyplax serrata</em> was shown to form a complex genetic structure, with a strictly specific S lineage living on <em>Apodemus flavicollis</em>, and a less specific N lineage on <em>A. flavicollis</em> and <em>Apodemus sylvaticus</em>. Moreover, the S lineage formed two mitochondrial clades with geographically exclusive distributions and a narrow hybrid zone, providing an opportunity to test the hypothesis that hybrids suffer a decrease in fitness. We sampled 451 individual lice from two host species at 103 localities. We used prevalences and intensities as proxies of fitness, which the parasites realize on their host. The S lineage, strictly specific to <em>Apodemus flavicollis</em>, reached significantly higher prevalences and intensities on its host compared with the N lineage. Conversely, the N lineage occurred with high prevalence and intensity on <em>A. sylvaticus</em> but tended to use also <em>A. flavicollis</em> when the louse populations became too dense. We discuss possible mechanisms behind this difference (particularly interspecific competition as a typical phenomenon in the specialist/generalist systems). We conclude that a parasite’s “choice”, not accessibility of the host or interspecific competition, is the main factor affecting the louse prevalences. We suggest that historical differences in geographic distribution of both lice and mice may provide a possible explanation for the observed life strategy differences. In contrast to the convincing picture in S and N lineage prevalences, we did not detect an expected drop in fitness in hybrids. We consider instability of the hybrid zone, or decline in abundance of the respective hosts, as possible explanations for this result.</div></div>","PeriodicalId":13725,"journal":{"name":"International journal for parasitology","volume":"55 1","pages":"Pages 27-34"},"PeriodicalIF":3.7,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142464482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}